Post-systolic relaxation of the HEART, especially the HEART VENTRICLES.
Period of contraction of the HEART, especially of the HEART VENTRICLES.
Contractile activity of the MYOCARDIUM.
The hemodynamic and electrophysiological action of the left HEART VENTRICLE. Its measurement is an important aspect of the clinical evaluation of patients with heart disease to determine the effects of the disease on cardiac performance.
Measurement of intracardiac blood flow using an M-mode and/or two-dimensional (2-D) echocardiogram while simultaneously recording the spectrum of the audible Doppler signal (e.g., velocity, direction, amplitude, intensity, timing) reflected from the moving column of red blood cells.
The lower right and left chambers of the heart. The right ventricle pumps venous BLOOD into the LUNGS and the left ventricle pumps oxygenated blood into the systemic arterial circulation.
A value equal to the total volume flow divided by the cross-sectional area of the vascular bed.
The valve between the left atrium and left ventricle of the heart.
Ultrasonic recording of the size, motion, and composition of the heart and surrounding tissues. The standard approach is transthoracic.
The hemodynamic and electrophysiological action of the HEART VENTRICLES.
The domestic dog, Canis familiaris, comprising about 400 breeds, of the carnivore family CANIDAE. They are worldwide in distribution and live in association with people. (Walker's Mammals of the World, 5th ed, p1065)
The hollow, muscular organ that maintains the circulation of the blood.
The circulation of blood through the CORONARY VESSELS of the HEART.
Theoretical representations that simulate the behavior or activity of the cardiovascular system, processes, or phenomena; includes the use of mathematical equations, computers and other electronic equipment.
The volume of the HEART, usually relating to the volume of BLOOD contained within it at various periods of the cardiac cycle. The amount of blood ejected from a ventricle at each beat is STROKE VOLUME.
Echocardiography applying the Doppler effect, with the superposition of flow information as colors on a gray scale in a real-time image.
Echocardiography applying the Doppler effect, with velocity detection combined with range discrimination. Short bursts of ultrasound are transmitted at regular intervals and the echoes are demodulated as they return.
Act of listening for sounds within the heart.
The amount of BLOOD pumped out of the HEART per beat, not to be confused with cardiac output (volume/time). It is calculated as the difference between the end-diastolic volume and the end-systolic volume.
The movement and the forces involved in the movement of the blood through the CARDIOVASCULAR SYSTEM.
A condition in which the LEFT VENTRICLE of the heart was functionally impaired. This condition usually leads to HEART FAILURE; MYOCARDIAL INFARCTION; and other cardiovascular complications. Diagnosis is made by measuring the diminished ejection fraction and a depressed level of motility of the left ventricular wall.
Timing the acquisition of imaging data to specific points in the cardiac cycle to minimize image blurring and other motion artifacts.
The pressure within a CARDIAC VENTRICLE. Ventricular pressure waveforms can be measured in the beating heart by catheterization or estimated using imaging techniques (e.g., DOPPLER ECHOCARDIOGRAPHY). The information is useful in evaluating the function of the MYOCARDIUM; CARDIAC VALVES; and PERICARDIUM, particularly with simultaneous measurement of other (e.g., aortic or atrial) pressures.
PRESSURE of the BLOOD on the ARTERIES and other BLOOD VESSELS.
Graphic registration of the heart sounds picked up as vibrations and transformed by a piezoelectric crystal microphone into a varying electrical output according to the stresses imposed by the sound waves. The electrical output is amplified by a stethograph amplifier and recorded by a device incorporated into the electrocardiograph or by a multichannel recording machine.
The graphic recording of chest wall movement due to cardiac impulses.
A twisting deformation of a solid body about an axis. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)
Resistance and recovery from distortion of shape.
A conical fibro-serous sac surrounding the HEART and the roots of the great vessels (AORTA; VENAE CAVAE; PULMONARY ARTERY). Pericardium consists of two sacs: the outer fibrous pericardium and the inner serous pericardium. The latter consists of an outer parietal layer facing the fibrous pericardium, and an inner visceral layer (epicardium) resting next to the heart, and a pericardial cavity between these two layers.
This structure includes the thin muscular atrial septum between the two HEART ATRIA, and the thick muscular ventricular septum between the two HEART VENTRICLES.
The hemodynamic and electrophysiological action of the right HEART VENTRICLE.
The number of times the HEART VENTRICLES contract per unit of time, usually per minute.
The hemodynamic and electrophysiological action of the LEFT ATRIUM.
The muscle tissue of the HEART. It is composed of striated, involuntary muscle cells (MYOCYTES, CARDIAC) connected to form the contractile pump to generate blood flow.
The innermost layer of the heart, comprised of endothelial cells.
The heart of the fetus of any viviparous animal. It refers to the heart in the postembryonic period and is differentiated from the embryonic heart (HEART/embryology) only on the basis of time.
The sounds heard over the cardiac region produced by the functioning of the heart. There are four distinct sounds: the first occurs at the beginning of SYSTOLE and is heard as a "lubb" sound; the second is produced by the closing of the AORTIC VALVE and PULMONARY VALVE and is heard as a "dupp" sound; the third is produced by vibrations of the ventricular walls when suddenly distended by the rush of blood from the HEART ATRIA; and the fourth is produced by atrial contraction and ventricular filling.
The hemodynamic and electrophysiological action of the HEART ATRIA.
Backflow of blood from the LEFT VENTRICLE into the LEFT ATRIUM due to imperfect closure of the MITRAL VALVE. This can lead to mitral valve regurgitation.
A malformation that is characterized by a muscle bridge over a segment of the CORONARY ARTERIES. Systolic contractions of the muscle bridge can lead to narrowing of coronary artery; coronary compression; MYOCARDIAL ISCHEMIA; MYOCARDIAL INFARCTION; and SUDDEN CARDIAC DEATH.
Pathological condition characterized by the backflow of blood from the ASCENDING AORTA back into the LEFT VENTRICLE, leading to regurgitation. It is caused by diseases of the AORTIC VALVE or its surrounding tissue (aortic root).
Recording of the moment-to-moment electromotive forces of the HEART as projected onto various sites on the body's surface, delineated as a scalar function of time. The recording is monitored by a tracing on slow moving chart paper or by observing it on a cardioscope, which is a CATHODE RAY TUBE DISPLAY.
Pathological conditions involving the HEART including its structural and functional abnormalities.
A type of imaging technique used primarily in the field of cardiology. By coordinating the fast gradient-echo MRI sequence with retrospective ECG-gating, numerous short time frames evenly spaced in the cardiac cycle are produced. These images are laced together in a cinematic display so that wall motion of the ventricles, valve motion, and blood flow patterns in the heart and great vessels can be visualized.
The veins and arteries of the HEART.
The chambers of the heart, to which the BLOOD returns from the circulation.
A form of CARDIAC MUSCLE disease in which the ventricular walls are excessively rigid, impeding ventricular filling. It is marked by reduced diastolic volume of either or both ventricles but normal or nearly normal systolic function. It may be idiopathic or associated with other diseases (ENDOMYOCARDIAL FIBROSIS or AMYLOIDOSIS) causing interstitial fibrosis.
Rhythmic, intermittent propagation of a fluid through a BLOOD VESSEL or piping system, in contrast to constant, smooth propagation, which produces laminar flow.
Enlargement of the LEFT VENTRICLE of the heart. This increase in ventricular mass is attributed to sustained abnormal pressure or volume loads and is a contributor to cardiovascular morbidity and mortality.
Elements of limited time intervals, contributing to particular results or situations.
Radiography of the heart and great vessels after injection of a contrast medium.
A fetal blood vessel connecting the pulmonary artery with the descending aorta.
Narrowing of the passage through the MITRAL VALVE due to FIBROSIS, and CALCINOSIS in the leaflets and chordal areas. This elevates the left atrial pressure which, in turn, raises pulmonary venous and capillary pressure leading to bouts of DYSPNEA and TACHYCARDIA during physical exertion. RHEUMATIC FEVER is its primary cause.
Procedures in which placement of CARDIAC CATHETERS is performed for therapeutic or diagnostic procedures.
The hemodynamic and electrophysiological action of the RIGHT ATRIUM.
The valve between the left ventricle and the ascending aorta which prevents backflow into the left ventricle.
Conical muscular projections from the walls of the cardiac ventricles, attached to the cusps of the atrioventricular valves by the chordae tendineae.
The repeating contractile units of the MYOFIBRIL, delimited by Z bands along its length.
Regulation of the rate of contraction of the heart muscles by an artificial pacemaker.
A form of CARDIAC MUSCLE disease that is characterized by ventricular dilation, VENTRICULAR DYSFUNCTION, and HEART FAILURE. Risk factors include SMOKING; ALCOHOL DRINKING; HYPERTENSION; INFECTION; PREGNANCY; and mutations in the LMNA gene encoding LAMIN TYPE A, a NUCLEAR LAMINA protein.
Echocardiography amplified by the addition of depth to the conventional two-dimensional ECHOCARDIOGRAPHY visualizing only the length and width of the heart. Three-dimensional ultrasound imaging was first described in 1961 but its application to echocardiography did not take place until 1974. (Mayo Clin Proc 1993;68:221-40)
A valve situated at the entrance to the pulmonary trunk from the right ventricle.
A condition in which the RIGHT VENTRICLE of the heart was functionally impaired. This condition usually leads to HEART FAILURE or MYOCARDIAL INFARCTION, and other cardiovascular complications. Diagnosis is made by measuring the diminished ejection fraction and a depressed level of motility of the right ventricular wall.
Distensibility measure of a chamber such as the lungs (LUNG COMPLIANCE) or bladder. Compliance is expressed as a change in volume per unit change in pressure.
A giant elastic protein of molecular mass ranging from 2,993 kDa (cardiac), 3,300 kDa (psoas), to 3,700 kDa (soleus) having a kinase domain. The amino- terminal is involved in a Z line binding, and the carboxy-terminal region is bound to the myosin filament with an overlap between the counter-connectin filaments at the M line.
A heterogeneous condition in which the heart is unable to pump out sufficient blood to meet the metabolic need of the body. Heart failure can be caused by structural defects, functional abnormalities (VENTRICULAR DYSFUNCTION), or a sudden overload beyond its capacity. Chronic heart failure is more common than acute heart failure which results from sudden insult to cardiac function, such as MYOCARDIAL INFARCTION.
Inflammation of the PERICARDIUM that is characterized by the fibrous scarring and adhesion of both serous layers, the VISCERAL PERICARDIUM and the PARIETAL PERICARDIUM leading to the loss of pericardial cavity. The thickened pericardium severely restricts cardiac filling. Clinical signs include FATIGUE, muscle wasting, and WEIGHT LOSS.
The range or frequency distribution of a measurement in a population (of organisms, organs or things) that has not been selected for the presence of disease or abnormality.
Motion pictures of the passage of contrast medium through blood vessels.
The volume of BLOOD passing through the HEART per unit of time. It is usually expressed as liters (volume) per minute so as not to be confused with STROKE VOLUME (volume per beat).
The force that opposes the flow of BLOOD through a vascular bed. It is equal to the difference in BLOOD PRESSURE across the vascular bed divided by the CARDIAC OUTPUT.
The flow of BLOOD through or around an organ or region of the body.
The statistical reproducibility of measurements (often in a clinical context), including the testing of instrumentation or techniques to obtain reproducible results. The concept includes reproducibility of physiological measurements, which may be used to develop rules to assess probability or prognosis, or response to a stimulus; reproducibility of occurrence of a condition; and reproducibility of experimental results.
A type of stress exerted uniformly in all directions. Its measure is the force exerted per unit area. (McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)
Any of the ruminant mammals with curved horns in the genus Ovis, family Bovidae. They possess lachrymal grooves and interdigital glands, which are absent in GOATS.
The valve consisting of three cusps situated between the right atrium and right ventricle of the heart.
A purely physical condition which exists within any material because of strain or deformation by external forces or by non-uniform thermal expansion; expressed quantitatively in units of force per unit area.
The blood pressure as recorded after wedging a CATHETER in a small PULMONARY ARTERY; believed to reflect the PRESSURE in the pulmonary CAPILLARIES.
Ultrasonic recording of the size, motion, and composition of the heart and surrounding tissues using a transducer placed in the esophagus.
Non-invasive imaging methods based on the mechanical response of an object to a vibrational or impulsive force. It is used for determining the viscoelastic properties of tissue, and thereby differentiating soft from hard inclusions in tissue such as microcalcifications, and some cancer lesions. Most techniques use ultrasound to create the images - eliciting the response with an ultrasonic radiation force and/or recording displacements of the tissue by Doppler ultrasonography.
Striated muscle cells found in the heart. They are derived from cardiac myoblasts (MYOBLASTS, CARDIAC).
The main trunk of the systemic arteries.
A form of CARDIAC MUSCLE disease, characterized by left and/or right ventricular hypertrophy (HYPERTROPHY, LEFT VENTRICULAR; HYPERTROPHY, RIGHT VENTRICULAR), frequent asymmetrical involvement of the HEART SEPTUM, and normal or reduced left ventricular volume. Risk factors include HYPERTENSION; AORTIC STENOSIS; and gene MUTATION; (FAMILIAL HYPERTROPHIC CARDIOMYOPATHY).
Backflow of blood from the RIGHT VENTRICLE into the RIGHT ATRIUM due to imperfect closure of the TRICUSPID VALVE.
Methods developed to aid in the interpretation of ultrasound, radiographic images, etc., for diagnosis of disease.
The rhythmical expansion and contraction of an ARTERY produced by waves of pressure caused by the ejection of BLOOD from the left ventricle of the HEART as it contracts.
A benign neoplasm derived from connective tissue, consisting chiefly of polyhedral and stellate cells that are loosely embedded in a soft mucoid matrix, thereby resembling primitive mesenchymal tissue. It occurs frequently intramuscularly where it may be mistaken for a sarcoma. It appears also in the jaws and the skin. (From Stedman, 25th ed)
The visualization of tissues during pregnancy through recording of the echoes of ultrasonic waves directed into the body. The procedure may be applied with reference to the mother or the fetus and with reference to organs or the detection of maternal or fetal disease.
A combination of congenital heart defects consisting of four key features including VENTRICULAR SEPTAL DEFECTS; PULMONARY STENOSIS; RIGHT VENTRICULAR HYPERTROPHY; and a dextro-positioned AORTA. In this condition, blood from both ventricles (oxygen-rich and oxygen-poor) is pumped into the body often causing CYANOSIS.
Physical motion, i.e., a change in position of a body or subject as a result of an external force. It is distinguished from MOVEMENT, a process resulting from biological activity.
The failure by the observer to measure or identify a phenomenon accurately, which results in an error. Sources for this may be due to the observer's missing an abnormality, or to faulty technique resulting in incorrect test measurement, or to misinterpretation of the data. Two varieties are inter-observer variation (the amount observers vary from one another when reporting on the same material) and intra-observer variation (the amount one observer varies between observations when reporting more than once on the same material).
A technique of inputting two-dimensional images into a computer and then enhancing or analyzing the imagery into a form that is more useful to the human observer.
The circulation of the BLOOD through the LUNGS.
A group of diseases in which the dominant feature is the involvement of the CARDIAC MUSCLE itself. Cardiomyopathies are classified according to their predominant pathophysiological features (DILATED CARDIOMYOPATHY; HYPERTROPHIC CARDIOMYOPATHY; RESTRICTIVE CARDIOMYOPATHY) or their etiological/pathological factors (CARDIOMYOPATHY, ALCOHOLIC; ENDOCARDIAL FIBROELASTOSIS).
Treatment process involving the injection of fluid into an organ or tissue.
The properties, processes, and behavior of biological systems under the action of mechanical forces.
Enlargement of the HEART, usually indicated by a cardiothoracic ratio above 0.50. Heart enlargement may involve the right, the left, or both HEART VENTRICLES or HEART ATRIA. Cardiomegaly is a nonspecific symptom seen in patients with chronic systolic heart failure (HEART FAILURE) or several forms of CARDIOMYOPATHIES.
A device that substitutes for a heart valve. It may be composed of biological material (BIOPROSTHESIS) and/or synthetic material.
Volume of circulating BLOOD. It is the sum of the PLASMA VOLUME and ERYTHROCYTE VOLUME.
The vessels carrying blood away from the heart.
A network of tubules and sacs in the cytoplasm of SKELETAL MUSCLE FIBERS that assist with muscle contraction and relaxation by releasing and storing calcium ions.
The condition of an anatomical structure's being dilated beyond normal dimensions.
A method of non-invasive, continuous measurement of MICROCIRCULATION. The technique is based on the values of the DOPPLER EFFECT of low-power laser light scattered randomly by static structures and moving tissue particulates.
Non-invasive method of demonstrating internal anatomy based on the principle that atomic nuclei in a strong magnetic field absorb pulses of radiofrequency energy and emit them as radiowaves which can be reconstructed into computerized images. The concept includes proton spin tomographic techniques.
Observation of a population for a sufficient number of persons over a sufficient number of years to generate incidence or mortality rates subsequent to the selection of the study group.
Abrupt changes in the membrane potential that sweep along the CELL MEMBRANE of excitable cells in response to excitation stimuli.
The short wide vessel arising from the conus arteriosus of the right ventricle and conveying unaerated blood to the lungs.
A basic element found in nearly all organized tissues. It is a member of the alkaline earth family of metals with the atomic symbol Ca, atomic number 20, and atomic weight 40. Calcium is the most abundant mineral in the body and combines with phosphorus to form calcium phosphate in the bones and teeth. It is essential for the normal functioning of nerves and muscles and plays a role in blood coagulation (as factor IV) and in many enzymatic processes.
A disorder of cardiac function caused by insufficient blood flow to the muscle tissue of the heart. The decreased blood flow may be due to narrowing of the coronary arteries (CORONARY ARTERY DISEASE), to obstruction by a thrombus (CORONARY THROMBOSIS), or less commonly, to diffuse narrowing of arterioles and other small vessels within the heart. Severe interruption of the blood supply to the myocardial tissue may result in necrosis of cardiac muscle (MYOCARDIAL INFARCTION).
An imbalance between myocardial functional requirements and the capacity of the CORONARY VESSELS to supply sufficient blood flow. It is a form of MYOCARDIAL ISCHEMIA (insufficient blood supply to the heart muscle) caused by a decreased capacity of the coronary vessels.
The presence of an increased amount of blood in a body part or an organ leading to congestion or engorgement of blood vessels. Hyperemia can be due to increase of blood flow into the area (active or arterial), or due to obstruction of outflow of blood from the area (passive or venous).
Radiography of the vascular system of the heart muscle after injection of a contrast medium.
Tumors in any part of the heart. They include primary cardiac tumors and metastatic tumors to the heart. Their interference with normal cardiac functions can cause a wide variety of symptoms including HEART FAILURE; CARDIAC ARRHYTHMIAS; or EMBOLISM.
Narrowing or constriction of a coronary artery.
Ultrasonography applying the Doppler effect, with frequency-shifted ultrasound reflections produced by moving targets (usually red blood cells) in the bloodstream along the ultrasound axis in direct proportion to the velocity of movement of the targets, to determine both direction and velocity of blood flow. (Stedman, 25th ed)
The geometric and structural changes that the HEART VENTRICLES undergo, usually following MYOCARDIAL INFARCTION. It comprises expansion of the infarct and dilatation of the healthy ventricle segments. While most prevalent in the left ventricle, it can also occur in the right ventricle.
An impulse-conducting system composed of modified cardiac muscle, having the power of spontaneous rhythmicity and conduction more highly developed than the rest of the heart.
A tetrameric calcium release channel in the SARCOPLASMIC RETICULUM membrane of SMOOTH MUSCLE CELLS, acting oppositely to SARCOPLASMIC RETICULUM CALCIUM-TRANSPORTING ATPASES. It is important in skeletal and cardiac excitation-contraction coupling and studied by using RYANODINE. Abnormalities are implicated in CARDIAC ARRHYTHMIAS and MUSCULAR DISEASES.
Persistently high systemic arterial BLOOD PRESSURE. Based on multiple readings (BLOOD PRESSURE DETERMINATION), hypertension is currently defined as when SYSTOLIC PRESSURE is consistently greater than 140 mm Hg or when DIASTOLIC PRESSURE is consistently 90 mm Hg or more.
Any disturbances of the normal rhythmic beating of the heart or MYOCARDIAL CONTRACTION. Cardiac arrhythmias can be classified by the abnormalities in HEART RATE, disorders of electrical impulse generation, or impulse conduction.
A catecholamine derivative with specificity for BETA-1 ADRENERGIC RECEPTORS. It is commonly used as a cardiotonic agent after CARDIAC SURGERY and during DOBUTAMINE STRESS ECHOCARDIOGRAPHY.
In screening and diagnostic tests, the probability that a person with a positive test is a true positive (i.e., has the disease), is referred to as the predictive value of a positive test; whereas, the predictive value of a negative test is the probability that the person with a negative test does not have the disease. Predictive value is related to the sensitivity and specificity of the test.
The age of the conceptus, beginning from the time of FERTILIZATION. In clinical obstetrics, the gestational age is often estimated as the time from the last day of the last MENSTRUATION which is about 2 weeks before OVULATION and fertilization.
Small pumps, often implantable, designed for temporarily assisting the heart, usually the LEFT VENTRICLE, to pump blood. They consist of a pumping chamber and a power source, which may be partially or totally external to the body and activated by electromagnetic motors.
Procedures for finding the mathematical function which best describes the relationship between a dependent variable and one or more independent variables. In linear regression (see LINEAR MODELS) the relationship is constrained to be a straight line and LEAST-SQUARES ANALYSIS is used to determine the best fit. In logistic regression (see LOGISTIC MODELS) the dependent variable is qualitative rather than continuously variable and LIKELIHOOD FUNCTIONS are used to find the best relationship. In multiple regression, the dependent variable is considered to depend on more than a single independent variable.
Binary classification measures to assess test results. Sensitivity or recall rate is the proportion of true positives. Specificity is the probability of correctly determining the absence of a condition. (From Last, Dictionary of Epidemiology, 2d ed)
The species Oryctolagus cuniculus, in the family Leporidae, order LAGOMORPHA. Rabbits are born in burrows, furless, and with eyes and ears closed. In contrast with HARES, rabbits have 22 chromosome pairs.
The gradual irreversible changes in structure and function of an organism that occur as a result of the passage of time.
Statistical models in which the value of a parameter for a given value of a factor is assumed to be equal to a + bx, where a and b are constants. The models predict a linear regression.

Ambulatory blood pressure monitoring and progression in patients with IgA nephropathy. (1/2997)

BACKGROUND: Hypertension is a recognized marker of poor prognosis in IgA nephropathy. METHODS: The present study investigated the prevalence of white-coat hypertension, the diurnal rhythm of blood pressure (BP), the effectiveness of antihypertensive drug therapy, and the effect of the above on the progression of the kidney disease in IgA nephropathy. One hundred twenty-six IgA nephropathy patients were selected consecutively for 24-h ambulatory blood pressure monitoring (ABPM). Fifty-five patients were normotensive and 71 were treated hypertensives. Their antihypertensive drugs were angiotensin-converting enzyme inhibitors (ACEI) alone or in combination with calcium-channel blockers (CCB). RESULTS: The mean night-time BP of normotensives (108+/-9/67+/-6 mmHg) was significantly lower than their day-time BP (125+/-8/82+/-7 mmHg, P<0.05). There was no significant difference between the mean day-time and night-time BP in hypertensive patients (125+/-9/82+/-7 mmHg vs 128+/-10/85+/-9 mmHg). The circadian variation of BP was preserved ('dippers') in 82% of the normotensive and 7% of the hypertensive patients (P<0.001). There were 10 'white-coat hypertensives' among the patients classified as normotensives with ABPM (mean office blood pressure 149+/-7/96+/-8 mmHg, 24-h blood pressure 127+/-6/83+/-5 mmHg, P<0.05) and 14 among treated hypertensives (mean office BP 152+/-8/98+/-6 mmHg, 24-h BP 130+/-4/85+/-8 mmHg, P<0.05). There was no difference in mean day-time BP among normotensive and treated hypertensive patients (125+/-8/81+/-5 mmHg vs 128+/-10/85+/-9 mmHg). Hypertensives had significantly higher night-time BP (125+/-9/85+/-9 mmHg) than normotensives (108+/-9/67+/-6 mmHg, P<0.001). There was no difference in serum creatinine levels among the different groups at the time of the ABPM. However, thirty-six+/-4.1 months after the ABPM, hypertensive patients (n=52) had higher serum creatinine levels (124+/-32 micromol/l) than at the time of the ABPM (101+/-28 micromol/l). The serum creatinine of normotensive patients (n=43) did not change during the follow-up period. 'Non-dipper' normotensives (n=10) had significantly higher serum creatinine levels at the end of the follow-up period than at its beginning (106+/-17 micromol/l vs 89+/-18 micromol/l, P<0.05). There was no increase in serum creatinine of 'dipper' normotensives. The mean serum creatinine of 'white-coat hypertensives' was significantly higher at the end of the study period than at its beginning. CONCLUSIONS: There is no diurnal blood pressure variation in most of the hypertensive IgA nephropathy patients. ACEI and CCB treatment have better effect on day-time than night-time hypertension. The lack of the circadian rhythm and 'white-coat hypertension' seems to accelerate the progression of IgA nephropathy.  (+info)

Restriction of placental and fetal growth in sheep alters fetal blood pressure responses to angiotensin II and captopril. (2/2997)

1. We have measured arterial blood pressure between 115 and 145 days gestation in normally grown fetal sheep (control group; n = 16) and in fetal sheep in which growth was restricted by experimental restriction of placental growth and development (PR group; n = 13). There was no significant difference in the mean gestational arterial blood pressure between the PR (42.7 +/- 2.6 mmHg) and control groups (37.7 +/- 2.3 mmHg). Mean arterial blood pressure and arterial PO2 were significantly correlated in control animals (r = 0.53, P < 0.05, n = 16), but not in the PR group. 2. There were no changes in mean arterial blood pressure in either the PR or control groups in response to captopril (7.5 microg captopril min-1; PR group n = 7, control group n = 6) between 115 and 125 days gestation. After 135 days gestation, there was a significant decrease (P < 0.05) in the fetal arterial blood pressure in the PR group but not in the control group during the captopril infusion (15 microg captopril min-1; PR group n = 7, control group n = 6). 3. There was a significant effect (F = 14.75; P < 0.001) of increasing doses of angiotensin II on fetal diastolic blood pressure in the PR and control groups. The effects of angiotensin II were different (F = 8.67; P < 0.05) in the PR and control groups at both gestational age ranges. 4. These data indicate that arterial blood pressure may be maintained by different mechanisms in growth restricted fetuses and normally grown counterparts and suggests a role for the fetal renin-angiotensin system in the maintenance of blood pressure in growth restricted fetuses.  (+info)

Contribution of L-type Ca2+ current to electrical activity in sinoatrial nodal myocytes of rabbits. (3/2997)

The role of L-type calcium current (ICa,L) in impulse generation was studied in single sinoatrial nodal myocytes of the rabbit, with the use of the amphotericin-perforated patch-clamp technique. Nifedipine, at a concentration of 5 microM, was used to block ICa,L. At this concentration, nifedipine selectively blocked ICa,L for 81% without affecting the T-type calcium current (ICa,T), the fast sodium current, the delayed rectifier current (IK), and the hyperpolarization-activated inward current. Furthermore, we did not observe the sustained inward current. The selective action of nifedipine on ICa,L enabled us to determine the activation threshold of ICa,L, which was around -60 mV. As nifedipine (5 microM) abolished spontaneous activity, we used a combined voltage- and current-clamp protocol to study the effects of ICa,L blockade on repolarization and diastolic depolarization. This protocol mimics the action potential such that the repolarization and subsequent diastolic depolarization are studied in current-clamp conditions. Nifedipine significantly decreased action potential duration at 50% repolarization and reduced diastolic depolarization rate over the entire diastole. Evidence was found that recovery from inactivation of ICa,L occurs during repolarization, which makes ICa,L available already early in diastole. We conclude that ICa,L contributes significantly to the net inward current during diastole and can modulate the entire diastolic depolarization.  (+info)

Changes in porcine transmitral flow velocity pattern and its diastolic determinants during partial coronary occlusion. (4/2997)

OBJECTIVES: To define the mechanical determinants of transmitral flow and the effect of heart rate during regional ischemia. BACKGROUND: Myocardial ischemia changes the transmitral flow velocity pattern due to disease-induced changes in the heart's diastolic properties. METHODS: Regional ischemia was produced in 12 pigs by partially occluding the left anterior descending coronary artery until segment-length shortening in the ischemic region fell by 20%. Transmitral flow velocity patterns and their determinants were measured under two conditions, baseline and ischemia, at two heart rates, 70 and 90 beats/min. RESULTS: Regional ischemia had a significant effect on two determinants of filling: relaxation, which was slower, and chamber stiffness, which increased. These changes were associated with reduced contractility and increased myocardial stiffness, resulting in an early transmitral flow pattern that was flatter and narrower, but no change in the late flow pattern. Moderate increases in heart rate accelerated relaxation and decreased atrioventricular pressure gradient but had no effect on contractility or myocardial or chamber stiffness, resulting in an early transmitral flow pattern that was flatter and narrower and an increased late flow velocity. CONCLUSIONS: This model of regional ischemia leads to a flatter and narrower early transmitral flow velocity pattern and no change in late flow due to a combination of slowed left ventricular relaxation and increased chamber stiffness. Reflex increases in heart rate that accompany ischemia tend to mask this effect.  (+info)

Decreased left ventricular filling pressure 8 months after corrective surgery in a 55-year-old man with tetralogy of Fallot: adaptation for increased preload. (5/2997)

A 55-year-old man with tetralogy of Fallot underwent corrective surgery. Left ventricular filling pressure increased markedly with increased left ventricular volume one month after surgery, then decreased over the next 7 months, presumably due to increased left ventricular compliance.  (+info)

Cell death in acromegalic cardiomyopathy. (6/2997)

BACKGROUND: Prolonged untreated acromegaly leads to a nonspecific myopathy characterized by ventricular dysfunction and failure. However, the mechanisms responsible for the alterations of cardiac pump function remain to be defined. Because cell death is implicated in most cardiac disease processes, the possibility has been raised that myocyte apoptosis may occur in the acromegalic heart, contributing to the deterioration of ventricular hemodynamics. METHODS AND RESULTS: Ten acromegalic patients with diastolic dysfunction and 4 also with systolic dysfunction were subjected to electrocardiography, Holter monitoring, 2-dimensional echocardiography, cardiac catheterization, and biventricular and coronary angiography before surgical removal of a growth hormone-secreting pituitary adenoma. Endomyocardial biopsies were obtained and analyzed quantitatively in terms of tissue scarring and myocyte and nonmyocyte apoptosis. Myocardial samples from papillary muscles of patients who underwent valve replacement for mitral stenosis were used for comparison. The presence of apoptosis in myocytes and interstitial cells was determined by confocal microscopy with the use of 2 histochemical methods, consisting of terminal deoxynucleotidyl transferase (TdT) assay and Taq probe in situ ligation. Acromegaly was characterized by a 495-fold and 305-fold increase in apoptosis of myocytes and nonmyocytes, respectively. The magnitude of myocyte apoptosis correlated with the extent of impairment in ejection fraction and the duration of the disease. A similar correlation was found with the magnitude of collagen accumulation, indicative of previous myocyte necrosis. Myocyte death was independent from the hormonal levels of growth hormone and insulin-like growth factor-1. Apoptosis of interstitial cells did not correlate with ejection fraction. CONCLUSIONS: Myocyte cell death, apoptotic and necrotic in nature, may be critical for the development of ventricular dysfunction and its progression to cardiac failure with acromegaly.  (+info)

Hypertension treatment and the prevention of coronary heart disease in the elderly. (7/2997)

Both isolated systolic hypertension (>140 mm Hg/<90 mm Hg) and systolic/diastolic hypertension (>140 mm Hg/>90 mm Hg) are major risk factors for cardiovascular disease in the elderly. Specific antihypertensive drug therapy is available if lifestyle interventions fail to reduce blood pressure to a normal level. Diuretics and beta blockers both reduce the occurrence of adverse events related to cerebrovascular disease; however, diuretics are more effective in reducing events related to coronary heart disease. Treated patients are less likely to develop severe hypertension or congestive heart failure. In most instances, low-dose diuretic therapy should be used as initial antihypertensive therapy in the elderly. A long-acting dihydropyridine calcium channel blocker may be used as alternative therapy in elderly patients with isolated systolic hypertension. Trials are being conducted to evaluate the long-term effects of angiotensin converting enzyme inhibitors and angiotensin-II receptor blockers in elderly patients with uncomplicated hypertension.  (+info)

Early detection of anthracycline induced cardiotoxicity in asymptomatic patients with normal left ventricular systolic function: autonomic versus echocardiographic variables. (8/2997)

OBJECTIVE: To investigate left ventricular dysfunction in patients who had been treated with anthracycline based chemotherapy. METHODS: Autonomic function was compared with left ventricular diastolic function in 20 asymptomatic women with normal systolic function (left ventricular ejection fraction (LVEF) > 0.50) treated for breast cancer with high dose anthracycline based chemotherapy, and 20 age matched healthy controls. Left ventricular diastolic function was assessed echocardiographically by measuring the early peak flow velocity to atrial peak flow velocity ratio, isovolumic relaxation time, and deceleration time. Heart rate variability analysis was assessed for time domain and frequency domain parameters. RESULTS: The mean (SD) age of the patients was 45 (7) years and the mean LVEF was 0.59 (0.06). The time interval after the end of chemotherapy was 29 (27) months. One or more diastolic variables were abnormal in 50% of the patients. Heart rate variability was abnormal in 85% of patients. Mean values of both time domain and frequency domain parameters were decreased (p < 0.05), in particular the parasympathetic indices. CONCLUSIONS: Autonomic impairment occurs in a large proportion of asymptomatic patients with normal systolic left ventricular function after high dose anthracycline based chemotherapy. In particular, heart rate variability analysis may be a sensitive tool to identify the first signs of cardiotoxicity in these patients.  (+info)

Diastole is the phase of the cardiac cycle during which the heart muscle relaxes and the chambers of the heart fill with blood. It follows systole, the phase in which the heart muscle contracts and pumps blood out to the body. In a normal resting adult, diastole lasts for approximately 0.4-0.5 seconds during each heartbeat. The period of diastole is divided into two phases: early diastole and late diastole. During early diastole, the ventricles fill with blood due to the pressure difference between the atria and ventricles. During late diastole, the atrioventricular valves close, and the ventricles continue to fill with blood due to the relaxation of the ventricular muscle and the compliance of the ventricular walls. The duration and pressure changes during diastole are important for maintaining adequate cardiac output and blood flow to the body.

Systole is the phase of the cardiac cycle during which the heart muscle contracts to pump blood out of the heart. Specifically, it refers to the contraction of the ventricles, the lower chambers of the heart. This is driven by the action of the electrical conduction system of the heart, starting with the sinoatrial node and passing through the atrioventricular node and bundle branches to the Purkinje fibers.

During systole, the pressure within the ventricles increases as they contract, causing the aortic and pulmonary valves to open and allowing blood to be ejected into the systemic and pulmonary circulations, respectively. The duration of systole is typically shorter than that of diastole, the phase during which the heart muscle relaxes and the chambers fill with blood.

In clinical settings, the terms "systolic" and "diastolic" are often used to describe blood pressure measurements, with the former referring to the pressure exerted on the artery walls when the ventricles contract and eject blood, and the latter referring to the pressure when the ventricles are relaxed and filling with blood.

Myocardial contraction refers to the rhythmic and forceful shortening of heart muscle cells (myocytes) in the myocardium, which is the muscular wall of the heart. This process is initiated by electrical signals generated by the sinoatrial node, causing a wave of depolarization that spreads throughout the heart.

During myocardial contraction, calcium ions flow into the myocytes, triggering the interaction between actin and myosin filaments, which are the contractile proteins in the muscle cells. This interaction causes the myofilaments to slide past each other, resulting in the shortening of the sarcomeres (the functional units of muscle contraction) and ultimately leading to the contraction of the heart muscle.

Myocardial contraction is essential for pumping blood throughout the body and maintaining adequate circulation to vital organs. Any impairment in myocardial contractility can lead to various cardiac disorders, such as heart failure, cardiomyopathy, and arrhythmias.

Left ventricular function refers to the ability of the left ventricle (the heart's lower-left chamber) to contract and relax, thereby filling with and ejecting blood. The left ventricle is responsible for pumping oxygenated blood to the rest of the body. Its function is evaluated by measuring several parameters, including:

1. Ejection fraction (EF): This is the percentage of blood that is pumped out of the left ventricle with each heartbeat. A normal ejection fraction ranges from 55% to 70%.
2. Stroke volume (SV): The amount of blood pumped by the left ventricle in one contraction. A typical SV is about 70 mL/beat.
3. Cardiac output (CO): The total volume of blood that the left ventricle pumps per minute, calculated as the product of stroke volume and heart rate. Normal CO ranges from 4 to 8 L/minute.

Assessment of left ventricular function is crucial in diagnosing and monitoring various cardiovascular conditions such as heart failure, coronary artery disease, valvular heart diseases, and cardiomyopathies.

Doppler echocardiography is a type of ultrasound test that uses high-frequency sound waves to produce detailed images of the heart and its blood vessels. It measures the direction and speed of blood flow in the heart and major blood vessels leading to and from the heart. This helps to evaluate various conditions such as valve problems, congenital heart defects, and heart muscle diseases.

In Doppler echocardiography, a small handheld device called a transducer is placed on the chest, which emits sound waves that bounce off the heart and blood vessels. The transducer then picks up the returning echoes, which are processed by a computer to create moving images of the heart.

The Doppler effect is used to measure the speed and direction of blood flow. This occurs when the frequency of the sound waves changes as they bounce off moving objects, such as red blood cells. By analyzing these changes, the ultrasound machine can calculate the velocity and direction of blood flow in different parts of the heart.

Doppler echocardiography is a non-invasive test that does not require any needles or dyes. It is generally safe and painless, although patients may experience some discomfort from the pressure applied by the transducer on the chest. The test usually takes about 30 to 60 minutes to complete.

The heart ventricles are the two lower chambers of the heart that receive blood from the atria and pump it to the lungs or the rest of the body. The right ventricle pumps deoxygenated blood to the lungs, while the left ventricle pumps oxygenated blood to the rest of the body. Both ventricles have thick, muscular walls to generate the pressure necessary to pump blood through the circulatory system.

Blood flow velocity is the speed at which blood travels through a specific part of the vascular system. It is typically measured in units of distance per time, such as centimeters per second (cm/s) or meters per second (m/s). Blood flow velocity can be affected by various factors, including cardiac output, vessel diameter, and viscosity of the blood. Measuring blood flow velocity is important in diagnosing and monitoring various medical conditions, such as heart disease, stroke, and peripheral vascular disease.

The mitral valve, also known as the bicuspid valve, is a two-leaflet valve located between the left atrium and left ventricle in the heart. Its function is to ensure unidirectional flow of blood from the left atrium into the left ventricle during the cardiac cycle. The mitral valve consists of two leaflets (anterior and posterior), the chordae tendineae, papillary muscles, and the left atrial and ventricular myocardium. Dysfunction of the mitral valve can lead to various heart conditions such as mitral regurgitation or mitral stenosis.

Echocardiography is a medical procedure that uses sound waves to produce detailed images of the heart's structure, function, and motion. It is a non-invasive test that can help diagnose various heart conditions, such as valve problems, heart muscle damage, blood clots, and congenital heart defects.

During an echocardiogram, a transducer (a device that sends and receives sound waves) is placed on the chest or passed through the esophagus to obtain images of the heart. The sound waves produced by the transducer bounce off the heart structures and return to the transducer, which then converts them into electrical signals that are processed to create images of the heart.

There are several types of echocardiograms, including:

* Transthoracic echocardiography (TTE): This is the most common type of echocardiogram and involves placing the transducer on the chest.
* Transesophageal echocardiography (TEE): This type of echocardiogram involves passing a specialized transducer through the esophagus to obtain images of the heart from a closer proximity.
* Stress echocardiography: This type of echocardiogram is performed during exercise or medication-induced stress to assess how the heart functions under stress.
* Doppler echocardiography: This type of echocardiogram uses sound waves to measure blood flow and velocity in the heart and blood vessels.

Echocardiography is a valuable tool for diagnosing and managing various heart conditions, as it provides detailed information about the structure and function of the heart. It is generally safe, non-invasive, and painless, making it a popular choice for doctors and patients alike.

Ventricular function, in the context of cardiac medicine, refers to the ability of the heart's ventricles (the lower chambers) to fill with blood during the diastole phase and eject blood during the systole phase. The ventricles are primarily responsible for pumping oxygenated blood out to the body (left ventricle) and deoxygenated blood to the lungs (right ventricle).

There are several ways to assess ventricular function, including:

1. Ejection Fraction (EF): This is the most commonly used measure of ventricular function. It represents the percentage of blood that is ejected from the ventricle during each heartbeat. A normal left ventricular ejection fraction is typically between 55% and 70%.
2. Fractional Shortening (FS): This is another measure of ventricular function, which calculates the change in size of the ventricle during contraction as a percentage of the original size. A normal FS for the left ventricle is typically between 25% and 45%.
3. Stroke Volume (SV): This refers to the amount of blood that is pumped out of the ventricle with each heartbeat. SV is calculated by multiplying the ejection fraction by the end-diastolic volume (the amount of blood in the ventricle at the end of diastole).
4. Cardiac Output (CO): This is the total amount of blood that the heart pumps in one minute. It is calculated by multiplying the stroke volume by the heart rate.

Impaired ventricular function can lead to various cardiovascular conditions, such as heart failure, cardiomyopathy, and valvular heart disease. Assessing ventricular function is crucial for diagnosing these conditions, monitoring treatment response, and guiding clinical decision-making.

I believe there might be a misunderstanding in your question. "Dogs" is not a medical term or condition. It is the common name for a domesticated carnivore of the family Canidae, specifically the genus Canis, which includes wolves, foxes, and other extant and extinct species of mammals. Dogs are often kept as pets and companions, and they have been bred in a wide variety of forms and sizes for different purposes, such as hunting, herding, guarding, assisting police and military forces, and providing companionship and emotional support.

If you meant to ask about a specific medical condition or term related to dogs, please provide more context so I can give you an accurate answer.

In medical terms, the heart is a muscular organ located in the thoracic cavity that functions as a pump to circulate blood throughout the body. It's responsible for delivering oxygen and nutrients to the tissues and removing carbon dioxide and other wastes. The human heart is divided into four chambers: two atria on the top and two ventricles on the bottom. The right side of the heart receives deoxygenated blood from the body and pumps it to the lungs, while the left side receives oxygenated blood from the lungs and pumps it out to the rest of the body. The heart's rhythmic contractions and relaxations are regulated by a complex electrical conduction system.

Coronary circulation refers to the circulation of blood in the coronary vessels, which supply oxygenated blood to the heart muscle (myocardium) and drain deoxygenated blood from it. The coronary circulation system includes two main coronary arteries - the left main coronary artery and the right coronary artery - that branch off from the aorta just above the aortic valve. These arteries further divide into smaller branches, which supply blood to different regions of the heart muscle.

The left main coronary artery divides into two branches: the left anterior descending (LAD) artery and the left circumflex (LCx) artery. The LAD supplies blood to the front and sides of the heart, while the LCx supplies blood to the back and sides of the heart. The right coronary artery supplies blood to the lower part of the heart, including the right ventricle and the bottom portion of the left ventricle.

The veins that drain the heart muscle include the great cardiac vein, the middle cardiac vein, and the small cardiac vein, which merge to form the coronary sinus. The coronary sinus empties into the right atrium, allowing deoxygenated blood to enter the right side of the heart and be pumped to the lungs for oxygenation.

Coronary circulation is essential for maintaining the health and function of the heart muscle, as it provides the necessary oxygen and nutrients required for proper contraction and relaxation of the myocardium. Any disruption or blockage in the coronary circulation system can lead to serious consequences, such as angina, heart attack, or even death.

Cardiovascular models are simplified representations or simulations of the human cardiovascular system used in medical research, education, and training. These models can be physical, computational, or mathematical and are designed to replicate various aspects of the heart, blood vessels, and blood flow. They can help researchers study the structure and function of the cardiovascular system, test new treatments and interventions, and train healthcare professionals in diagnostic and therapeutic techniques.

Physical cardiovascular models may include artificial hearts, blood vessels, or circulation systems made from materials such as plastic, rubber, or silicone. These models can be used to study the mechanics of heart valves, the effects of different surgical procedures, or the impact of various medical devices on blood flow.

Computational and mathematical cardiovascular models use algorithms and equations to simulate the behavior of the cardiovascular system. These models may range from simple representations of a single heart chamber to complex simulations of the entire circulatory system. They can be used to study the electrical activity of the heart, the biomechanics of blood flow, or the distribution of drugs in the body.

Overall, cardiovascular models play an essential role in advancing our understanding of the human body and improving patient care.

Cardiac volume refers to the amount of blood contained within the heart chambers at any given point in time. It is a measure of the volume of blood that is being moved by the heart during each cardiac cycle, which includes both systole (contraction) and diastole (relaxation) phases.

There are several types of cardiac volumes that are commonly measured or estimated using medical imaging techniques such as echocardiography or cardiac magnetic resonance imaging (MRI). These include:

1. End-diastolic volume (EDV): This is the volume of blood in the heart chambers at the end of diastole, when the heart chambers are fully filled with blood.
2. End-systolic volume (ESV): This is the volume of blood in the heart chambers at the end of systole, when the heart chambers have contracted and ejected most of the blood.
3. Stroke volume (SV): This is the difference between the EDV and ESV, and represents the amount of blood that is pumped out of the heart with each beat.
4. Cardiac output (CO): This is the product of the stroke volume and heart rate, and represents the total amount of blood that is pumped by the heart in one minute.

Abnormalities in cardiac volumes can indicate various heart conditions such as heart failure, valvular heart disease, or cardiomyopathy.

Echocardiography, Doppler, color is a type of ultrasound test that uses sound waves to create detailed moving images of the heart and its blood vessels. In this technique, color Doppler is used to visualize the direction and speed of blood flow through the heart and great vessels. The movement of the red blood cells causes a change in frequency of the reflected sound waves (Doppler shift), which can be used to calculate the velocity and direction of the blood flow. By adding color to the Doppler image, it becomes easier for the interpreting physician to understand the complex three-dimensional motion of blood through the heart. This test is often used to diagnose and monitor various heart conditions, including valve disorders, congenital heart defects, and cardiac muscle diseases.

Echocardiography, Doppler, pulsed is a type of diagnostic medical test that uses ultrasound to create detailed images of the heart's structures and assess their function. In this technique, high-frequency sound waves are directed at the heart using a handheld device called a transducer, which is placed on the chest wall. The sound waves bounce off the heart structures and return to the transducer, which then sends the information to a computer that converts it into images.

Pulsed Doppler echocardiography is a specific type of Doppler ultrasound that allows for the measurement of blood flow velocities in the heart and great vessels. In this technique, the transducer emits short bursts or "pulses" of sound waves and then measures the time it takes for the echoes to return. By analyzing the frequency shifts of the returning echoes, the velocity and direction of blood flow can be determined. This information is particularly useful in evaluating valvular function, assessing the severity of valvular lesions, and identifying areas of turbulent or abnormal blood flow.

Overall, echocardiography, Doppler, pulsed is a valuable tool for diagnosing and managing a wide range of cardiovascular conditions, including heart valve disorders, congenital heart defects, cardiomyopathies, and pericardial diseases.

Heart auscultation is a medical procedure in which a healthcare professional uses a stethoscope to listen to the sounds produced by the heart. The process involves placing the stethoscope on various locations of the chest wall to hear different areas of the heart.

The sounds heard during auscultation are typically related to the opening and closing of the heart valves, as well as the turbulence created by blood flow through the heart chambers. These sounds can provide important clues about the structure and function of the heart, allowing healthcare professionals to diagnose various cardiovascular conditions such as heart murmurs, valvular disorders, and abnormal heart rhythms.

Heart auscultation is a key component of a physical examination and requires proper training and experience to interpret the findings accurately.

Stroke volume is a term used in cardiovascular physiology and medicine. It refers to the amount of blood that is pumped out of the left ventricle of the heart during each contraction (systole). Specifically, it is the difference between the volume of blood in the left ventricle at the end of diastole (when the ventricle is filled with blood) and the volume at the end of systole (when the ventricle has contracted and ejected its contents into the aorta).

Stroke volume is an important measure of heart function, as it reflects the ability of the heart to pump blood effectively to the rest of the body. A low stroke volume may indicate that the heart is not pumping efficiently, while a high stroke volume may suggest that the heart is working too hard. Stroke volume can be affected by various factors, including heart disease, high blood pressure, and physical fitness level.

The formula for calculating stroke volume is:

Stroke Volume = End-Diastolic Volume - End-Systolic Volume

Where end-diastolic volume (EDV) is the volume of blood in the left ventricle at the end of diastole, and end-systolic volume (ESV) is the volume of blood in the left ventricle at the end of systole.

Hemodynamics is the study of how blood flows through the cardiovascular system, including the heart and the vascular network. It examines various factors that affect blood flow, such as blood volume, viscosity, vessel length and diameter, and pressure differences between different parts of the circulatory system. Hemodynamics also considers the impact of various physiological and pathological conditions on these variables, and how they in turn influence the function of vital organs and systems in the body. It is a critical area of study in fields such as cardiology, anesthesiology, and critical care medicine.

Left ventricular dysfunction (LVD) is a condition characterized by the impaired ability of the left ventricle of the heart to pump blood efficiently during contraction. The left ventricle is one of the four chambers of the heart and is responsible for pumping oxygenated blood to the rest of the body.

LVD can be caused by various underlying conditions, such as coronary artery disease, cardiomyopathy, valvular heart disease, or hypertension. These conditions can lead to structural changes in the left ventricle, including remodeling, hypertrophy, and dilation, which ultimately impair its contractile function.

The severity of LVD is often assessed by measuring the ejection fraction (EF), which is the percentage of blood that is pumped out of the left ventricle during each contraction. A normal EF ranges from 55% to 70%, while an EF below 40% is indicative of LVD.

LVD can lead to various symptoms, such as shortness of breath, fatigue, fluid retention, and decreased exercise tolerance. It can also increase the risk of complications, such as heart failure, arrhythmias, and cardiac arrest. Treatment for LVD typically involves managing the underlying cause, along with medications to improve contractility, reduce fluid buildup, and control heart rate. In severe cases, devices such as implantable cardioverter-defibrillators (ICDs) or left ventricular assist devices (LVADs) may be required.

Cardiac-gated imaging techniques are medical diagnostic procedures that involve synchronizing the acquisition of data with the electrical activity of the heart, typically the R-wave of the electrocardiogram (ECG). This allows for the capture of images during specific phases of the cardiac cycle, reducing motion artifacts and improving image quality. These techniques are commonly used in various imaging modalities such as echocardiography, cardiac magnetic resonance imaging (MRI), and nuclear medicine studies like myocardial perfusion imaging. By obtaining images at specific points in the cardiac cycle, these techniques help assess heart function, wall motion abnormalities, valve function, and myocardial perfusion, ultimately aiding in the diagnosis and management of various cardiovascular diseases.

Ventricular pressure refers to the pressure within the ventricles, which are the lower chambers of the heart. In the left ventricle, the pressure measures the force that the blood exerts on the walls as it is pumped out to the rest of the body. In the right ventricle, the pressure measures the force of the blood being pumped into the pulmonary artery and ultimately to the lungs for oxygenation.

Normally, the left ventricular pressure ranges from 8-12 mmHg at rest when the heart is relaxed (diastolic pressure) and can increase up to 120-140 mmHg during contraction (systolic pressure). The right ventricular pressure is lower than the left, with a normal diastolic pressure of 0-6 mmHg and a systolic pressure ranging from 15-30 mmHg.

Abnormal ventricular pressures can indicate various heart conditions, such as heart failure, hypertension, or valvular heart disease. Regular monitoring of ventricular pressure is essential in managing these conditions and ensuring proper heart function.

Blood pressure is the force exerted by circulating blood on the walls of the blood vessels. It is measured in millimeters of mercury (mmHg) and is given as two figures:

1. Systolic pressure: This is the pressure when the heart pushes blood out into the arteries.
2. Diastolic pressure: This is the pressure when the heart rests between beats, allowing it to fill with blood.

Normal blood pressure for adults is typically around 120/80 mmHg, although this can vary slightly depending on age, sex, and other factors. High blood pressure (hypertension) is generally considered to be a reading of 130/80 mmHg or higher, while low blood pressure (hypotension) is usually defined as a reading below 90/60 mmHg. It's important to note that blood pressure can fluctuate throughout the day and may be affected by factors such as stress, physical activity, and medication use.

Phonocardiography is a non-invasive medical procedure that involves the graphical representation and analysis of sounds produced by the heart. It uses a device called a phonocardiograph to record these sounds, which are then displayed as waveforms on a screen. The procedure is often used in conjunction with other diagnostic techniques, such as electrocardiography (ECG), to help diagnose various heart conditions, including valvular heart disease and heart murmurs.

During the procedure, a specialized microphone called a phonendoscope is placed on the chest wall over the area of the heart. The microphone picks up the sounds generated by the heart's movements, such as the closing and opening of the heart valves, and transmits them to the phonocardiograph. The phonocardiograph then converts these sounds into a visual representation, which can be analyzed for any abnormalities or irregularities in the heart's function.

Phonocardiography is a valuable tool for healthcare professionals, as it can provide important insights into the health and functioning of the heart. By analyzing the waveforms produced during phonocardiography, doctors can identify any potential issues with the heart's valves or other structures, which may require further investigation or treatment. Overall, phonocardiography is an essential component of modern cardiac diagnostics, helping to ensure that patients receive accurate and timely diagnoses for their heart conditions.

Kinetocardiography (often abbreviated as KCG) is not a widely recognized or established medical term. However, in general terms, it appears to refer to a method of measuring and recording the motion or vibrations of the chest wall that may be related to cardiac activity. It's possible that this term is used in some specific research or technical contexts, but it does not have a standardized medical definition.

It's important to note that there is another term called "ballistocardiography" (BCG) which is a non-invasive method of measuring the mechanical forces generated by the heart and great vessels during each cardiac cycle. BCG can provide information about various aspects of cardiovascular function, such as stroke volume, contractility, and vascular compliance. However, kinetocardiography does not seem to be synonymous with ballistocardiography or any other established medical technique.

Mechanical torsion in a medical context refers to the twisting or rotational deformation of a body or structure due to an applied torque or force. This can occur in various biological structures, such as blood vessels, intestines, or muscles, leading to impaired function, pain, or even tissue necrosis if severe or prolonged.

For example, in the case of the gastrointestinal tract, torsion can cause a segment of the bowel to twist around its own axis, cutting off blood flow and causing ischemia or necrosis. This is a surgical emergency that requires prompt intervention to prevent further complications. Similarly, in the eye, torsion can refer to the rotation of the eyeball within the orbit, which can cause double vision or other visual disturbances.

In medicine, elasticity refers to the ability of a tissue or organ to return to its original shape after being stretched or deformed. This property is due to the presence of elastic fibers in the extracellular matrix of the tissue, which can stretch and recoil like rubber bands.

Elasticity is an important characteristic of many tissues, particularly those that are subjected to repeated stretching or compression, such as blood vessels, lungs, and skin. For example, the elasticity of the lungs allows them to expand and contract during breathing, while the elasticity of blood vessels helps maintain normal blood pressure by allowing them to expand and constrict in response to changes in blood flow.

In addition to its role in normal physiology, elasticity is also an important factor in the diagnosis and treatment of various medical conditions. For example, decreased elasticity in the lungs can be a sign of lung disease, while increased elasticity in the skin can be a sign of aging or certain genetic disorders. Medical professionals may use techniques such as pulmonary function tests or skin biopsies to assess elasticity and help diagnose these conditions.

The pericardium is the double-walled sac that surrounds the heart. It has an outer fibrous layer and an inner serous layer, which further divides into two parts: the parietal layer lining the fibrous pericardium and the visceral layer (epicardium) closely adhering to the heart surface.

The space between these two layers is filled with a small amount of lubricating serous fluid, allowing for smooth movement of the heart within the pericardial cavity. The pericardium provides protection, support, and helps maintain the heart's normal position within the chest while reducing friction during heart contractions.

The heart septum is the thick, muscular wall that divides the right and left sides of the heart. It consists of two main parts: the atrial septum, which separates the right and left atria (the upper chambers of the heart), and the ventricular septum, which separates the right and left ventricles (the lower chambers of the heart). A normal heart septum ensures that oxygen-rich blood from the lungs does not mix with oxygen-poor blood from the body. Any defect or abnormality in the heart septum is called a septal defect, which can lead to various congenital heart diseases.

Right Ventricular Function refers to the ability of the right ventricle (RV) of the heart to receive and eject blood during the cardiac cycle. The right ventricle is one of the four chambers of the heart and is responsible for pumping deoxygenated blood from the body to the lungs for re-oxygenation.

Right ventricular function can be assessed by measuring various parameters such as:

1. Right Ventricular Ejection Fraction (RVEF): It is the percentage of blood that is ejected from the right ventricle during each heartbeat. A normal RVEF ranges from 45-75%.
2. Right Ventricular Systolic Function: It refers to the ability of the right ventricle to contract and eject blood during systole (contraction phase). This can be assessed by measuring the tricuspid annular plane systolic excursion (TAPSE) or tissue Doppler imaging.
3. Right Ventricular Diastolic Function: It refers to the ability of the right ventricle to relax and fill with blood during diastole (relaxation phase). This can be assessed by measuring the right ventricular inflow pattern, tricuspid valve E/A ratio, or deceleration time.
4. Right Ventricular Afterload: It refers to the pressure that the right ventricle must overcome to eject blood into the pulmonary artery. Increased afterload can impair right ventricular function.

Abnormalities in right ventricular function can lead to various cardiovascular conditions such as pulmonary hypertension, heart failure, and arrhythmias.

Heart rate is the number of heartbeats per unit of time, often expressed as beats per minute (bpm). It can vary significantly depending on factors such as age, physical fitness, emotions, and overall health status. A resting heart rate between 60-100 bpm is generally considered normal for adults, but athletes and individuals with high levels of physical fitness may have a resting heart rate below 60 bpm due to their enhanced cardiovascular efficiency. Monitoring heart rate can provide valuable insights into an individual's health status, exercise intensity, and response to various treatments or interventions.

Left atrial function refers to the role and performance of the left atrium in the heart. The left atrium is the upper chamber on the left side of the heart that receives oxygenated blood from the lungs via the pulmonary veins and then contracts to help pump it into the left ventricle, which is the lower chamber that pumps blood out to the rest of the body.

The main functions of the left atrium include:

1. Receiving oxygen-rich blood from the lungs: The left atrium receives oxygenated blood from the pulmonary veins and acts as a reservoir for this blood before it is pumped into the left ventricle.
2. Contracting to help pump blood into the left ventricle: During atrial contraction, also known as atrial kick, the left atrium contracts and helps push blood into the left ventricle, increasing the amount of blood that can be ejected with each heartbeat.
3. Relaxing to receive more blood: Between heartbeats, the left atrium relaxes and fills up with more oxygenated blood from the lungs.
4. Contributing to heart rate regulation: The left atrium contains specialized cells called pacemaker cells that can help regulate the heart rate by initiating electrical impulses that trigger heart contractions.

Left atrial function is crucial for maintaining efficient cardiac output and overall cardiovascular health. Various conditions, such as heart failure, atrial fibrillation, and hypertension, can negatively impact left atrial function and contribute to the development of complications like stroke and reduced exercise tolerance.

The myocardium is the middle layer of the heart wall, composed of specialized cardiac muscle cells that are responsible for pumping blood throughout the body. It forms the thickest part of the heart wall and is divided into two sections: the left ventricle, which pumps oxygenated blood to the rest of the body, and the right ventricle, which pumps deoxygenated blood to the lungs.

The myocardium contains several types of cells, including cardiac muscle fibers, connective tissue, nerves, and blood vessels. The muscle fibers are arranged in a highly organized pattern that allows them to contract in a coordinated manner, generating the force necessary to pump blood through the heart and circulatory system.

Damage to the myocardium can occur due to various factors such as ischemia (reduced blood flow), infection, inflammation, or genetic disorders. This damage can lead to several cardiac conditions, including heart failure, arrhythmias, and cardiomyopathy.

The endocardium is the innermost layer of tissue that lines the chambers of the heart and the valves between them. It is a thin, smooth membrane that is in contact with the blood within the heart. This layer helps to maintain the heart's internal environment, facilitates the smooth movement of blood through the heart, and provides a protective barrier against infection and other harmful substances. The endocardium is composed of simple squamous epithelial cells called endothelial cells, which are supported by a thin layer of connective tissue.

The fetal heart is the cardiovascular organ that develops in the growing fetus during pregnancy. It starts to form around 22 days after conception and continues to develop throughout the first trimester. By the end of the eighth week of gestation, the fetal heart has developed enough to pump blood throughout the body.

The fetal heart is similar in structure to the adult heart but has some differences. It is smaller and more compact, with a four-chambered structure that includes two atria and two ventricles. The fetal heart also has unique features such as the foramen ovale, which is a hole between the right and left atria that allows blood to bypass the lungs, and the ductus arteriosus, a blood vessel that connects the pulmonary artery to the aorta and diverts blood away from the lungs.

The fetal heart is responsible for pumping oxygenated blood from the placenta to the rest of the body and returning deoxygenated blood back to the placenta for re-oxygenation. The rate of the fetal heartbeat is faster than that of an adult, typically ranging from 120 to 160 beats per minute. Fetal heart rate monitoring is a common method used during pregnancy and childbirth to assess the health and well-being of the developing fetus.

Heart sounds are the noises generated by the beating heart and the movement of blood through it. They are caused by the vibration of the cardiac structures, such as the valves, walls, and blood vessels, during the cardiac cycle.

There are two normal heart sounds, often described as "lub-dub," that can be heard through a stethoscope. The first sound (S1) is caused by the closure of the mitral and tricuspid valves at the beginning of systole, when the ventricles contract to pump blood out to the body and lungs. The second sound (S2) is produced by the closure of the aortic and pulmonary valves at the end of systole, as the ventricles relax and the ventricular pressure decreases, allowing the valves to close.

Abnormal heart sounds, such as murmurs, clicks, or extra sounds (S3 or S4), may indicate cardiac disease or abnormalities in the structure or function of the heart. These sounds can be evaluated through a process called auscultation, which involves listening to the heart with a stethoscope and analyzing the intensity, pitch, quality, and timing of the sounds.

Atrial function in a medical context refers to the role and performance of the two upper chambers of the heart, known as the atria. The main functions of the atria are to receive blood from the veins and help pump it into the ventricles, which are the lower pumping chambers of the heart.

The atria contract in response to electrical signals generated by the sinoatrial node, which is the heart's natural pacemaker. This contraction helps to fill the ventricles with blood before they contract and pump blood out to the rest of the body. Atrial function can be assessed through various diagnostic tests, such as echocardiograms or electrocardiograms (ECGs), which can help identify any abnormalities in atrial structure or electrical activity that may affect heart function.

Mitral valve insufficiency, also known as mitral regurgitation, is a cardiac condition in which the mitral valve located between the left atrium and left ventricle of the heart does not close properly, causing blood to flow backward into the atrium during contraction of the ventricle. This leads to an increased volume load on the left heart chamber and can result in symptoms such as shortness of breath, fatigue, and fluid retention. The condition can be caused by various factors including valve damage due to degenerative changes, infective endocarditis, rheumatic heart disease, or trauma. Treatment options include medication, mitral valve repair, or replacement surgery depending on the severity and underlying cause of the insufficiency.

Myocardial bridging is a congenital cardiovascular anomaly where a segment of a major epicardial coronary artery, usually the left anterior descending (LAD) coronary artery, passes between the muscle fibers of the heart (myocardium) instead of running over the surface. This results in the coronary artery being compressed or "bridged" by the contracting myocardium during systole (contraction phase of the heart cycle), which can lead to a decrease in blood flow to the affected area of the heart muscle.

Myocardial bridging is usually asymptomatic and discovered incidentally during coronary angiography or autopsy. However, in some cases, it may cause symptoms such as angina (chest pain), shortness of breath, or arrhythmias (irregular heartbeats) due to the compromised blood flow. The severity of the symptoms depends on the length and depth of the myocardial bridge and the degree of compression during systole.

While myocardial bridging is a benign condition in most cases, it can increase the risk of ischemia (reduced blood supply to the heart muscle) and adverse cardiac events such as myocardial infarction (heart attack) or sudden cardiac death in rare instances. Treatment options for symptomatic myocardial bridging include medications, lifestyle modifications, and invasive procedures such as percutaneous coronary intervention or coronary artery bypass grafting.

Aortic valve insufficiency, also known as aortic regurgitation or aortic incompetence, is a cardiac condition in which the aortic valve does not close properly during the contraction phase of the heart cycle. This allows blood to flow back into the left ventricle from the aorta, instead of being pumped out to the rest of the body. As a result, the left ventricle must work harder to maintain adequate cardiac output, which can lead to left ventricular enlargement and heart failure over time if left untreated.

The aortic valve is a trileaflet valve that lies between the left ventricle and the aorta. During systole (the contraction phase of the heart cycle), the aortic valve opens to allow blood to be pumped out of the left ventricle into the aorta and then distributed to the rest of the body. During diastole (the relaxation phase of the heart cycle), the aortic valve closes to prevent blood from flowing back into the left ventricle.

Aortic valve insufficiency can be caused by various conditions, including congenital heart defects, infective endocarditis, rheumatic heart disease, Marfan syndrome, and trauma. Symptoms of aortic valve insufficiency may include shortness of breath, fatigue, chest pain, palpitations, and edema (swelling). Diagnosis is typically made through physical examination, echocardiography, and other imaging studies. Treatment options depend on the severity of the condition and may include medication, surgery to repair or replace the aortic valve, or a combination of both.

Electrocardiography (ECG or EKG) is a medical procedure that records the electrical activity of the heart. It provides a graphic representation of the electrical changes that occur during each heartbeat. The resulting tracing, called an electrocardiogram, can reveal information about the heart's rate and rhythm, as well as any damage to its cells or abnormalities in its conduction system.

During an ECG, small electrodes are placed on the skin of the chest, arms, and legs. These electrodes detect the electrical signals produced by the heart and transmit them to a machine that amplifies and records them. The procedure is non-invasive, painless, and quick, usually taking only a few minutes.

ECGs are commonly used to diagnose and monitor various heart conditions, including arrhythmias, coronary artery disease, heart attacks, and electrolyte imbalances. They can also be used to evaluate the effectiveness of certain medications or treatments.

Heart disease is a broad term for a class of diseases that involve the heart or blood vessels. It's often used to refer to conditions that include:

1. Coronary artery disease (CAD): This is the most common type of heart disease. It occurs when the arteries that supply blood to the heart become hardened and narrowed due to the buildup of cholesterol and other substances, which can lead to chest pain (angina), shortness of breath, or a heart attack.

2. Heart failure: This condition occurs when the heart is unable to pump blood efficiently to meet the body's needs. It can be caused by various conditions, including coronary artery disease, high blood pressure, and cardiomyopathy.

3. Arrhythmias: These are abnormal heart rhythms, which can be too fast, too slow, or irregular. They can lead to symptoms such as palpitations, dizziness, and fainting.

4. Valvular heart disease: This involves damage to one or more of the heart's four valves, which control blood flow through the heart. Damage can be caused by various conditions, including infection, rheumatic fever, and aging.

5. Cardiomyopathy: This is a disease of the heart muscle that makes it harder for the heart to pump blood efficiently. It can be caused by various factors, including genetics, viral infections, and drug abuse.

6. Pericardial disease: This involves inflammation or other problems with the sac surrounding the heart (pericardium). It can cause chest pain and other symptoms.

7. Congenital heart defects: These are heart conditions that are present at birth, such as a hole in the heart or abnormal blood vessels. They can range from mild to severe and may require medical intervention.

8. Heart infections: The heart can become infected by bacteria, viruses, or parasites, leading to various symptoms and complications.

It's important to note that many factors can contribute to the development of heart disease, including genetics, lifestyle choices, and certain medical conditions. Regular check-ups and a healthy lifestyle can help reduce the risk of developing heart disease.

Magnetic Resonance Imaging (MRI) is a non-invasive diagnostic technique that uses a strong magnetic field and radio waves to create detailed cross-sectional images of the body's internal structures. In MRI, Cine is a specific mode of imaging that allows for the evaluation of moving structures, such as the heart, by acquiring and displaying a series of images in rapid succession. This technique is particularly useful in cardiac imaging, where it can help assess heart function, valve function, and blood flow. The term "Cine" refers to the continuous playback of these images, similar to watching a movie, allowing doctors to evaluate motion and timing within the heart.

Coronary vessels refer to the network of blood vessels that supply oxygenated blood and nutrients to the heart muscle, also known as the myocardium. The two main coronary arteries are the left main coronary artery and the right coronary artery.

The left main coronary artery branches off into the left anterior descending artery (LAD) and the left circumflex artery (LCx). The LAD supplies blood to the front of the heart, while the LCx supplies blood to the side and back of the heart.

The right coronary artery supplies blood to the right lower part of the heart, including the right atrium and ventricle, as well as the back of the heart.

Coronary vessel disease (CVD) occurs when these vessels become narrowed or blocked due to the buildup of plaque, leading to reduced blood flow to the heart muscle. This can result in chest pain, shortness of breath, or a heart attack.

The heart atria are the upper chambers of the heart that receive blood from the veins and deliver it to the lower chambers, or ventricles. There are two atria in the heart: the right atrium receives oxygen-poor blood from the body and pumps it into the right ventricle, which then sends it to the lungs to be oxygenated; and the left atrium receives oxygen-rich blood from the lungs and pumps it into the left ventricle, which then sends it out to the rest of the body. The atria contract before the ventricles during each heartbeat, helping to fill the ventricles with blood and prepare them for contraction.

Restrictive cardiomyopathy (RCM) is a type of heart muscle disorder characterized by impaired relaxation and filling of the lower chambers of the heart (the ventricles), leading to reduced pump function. This is caused by stiffening or rigidity of the heart muscle, often due to fibrosis or scarring. The stiffness prevents the ventricles from filling properly with blood during the diastolic phase, which can result in symptoms such as shortness of breath, fatigue, and fluid retention.

RCM is a less common form of cardiomyopathy compared to dilated or hypertrophic cardiomyopathies. It can be idiopathic (no known cause) or secondary to other conditions like amyloidosis, sarcoidosis, or storage diseases. Diagnosis typically involves a combination of medical history, physical examination, echocardiography, and sometimes cardiac MRI or biopsy. Treatment is focused on managing symptoms and addressing underlying causes when possible.

Pulsatile flow is a type of fluid flow that occurs in a rhythmic, wave-like pattern, typically seen in the cardiovascular system. It refers to the periodic variation in the volume or velocity of a fluid (such as blood) that is caused by the regular beating of the heart. In pulsatile flow, there are periods of high flow followed by periods of low or no flow, which creates a distinct pattern on a graph or tracing. This type of flow is important for maintaining proper function and health in organs and tissues throughout the body.

Left ventricular hypertrophy (LVH) is a medical condition in which the left ventricle of the heart undergoes an enlargement or thickening of its muscle wall. The left ventricle is the main pumping chamber of the heart that supplies oxygenated blood to the rest of the body.

In response to increased workload, such as hypertension (high blood pressure), aortic valve stenosis, or athletic training, the left ventricular muscle may thicken and enlarge. This process is called "hypertrophy." While some degree of hypertrophy can be adaptive in athletes, significant or excessive hypertrophy can lead to impaired relaxation and filling of the left ventricle during diastole, reduced pumping capacity, and decreased compliance of the chamber.

Left ventricular hypertrophy is often asymptomatic initially but can increase the risk of various cardiovascular complications such as heart failure, arrhythmias, myocardial infarction (heart attack), and sudden cardiac death over time. It is typically diagnosed through imaging techniques like echocardiography or cardiac MRI and confirmed by measuring the thickness of the left ventricular wall.

In the field of medicine, "time factors" refer to the duration of symptoms or time elapsed since the onset of a medical condition, which can have significant implications for diagnosis and treatment. Understanding time factors is crucial in determining the progression of a disease, evaluating the effectiveness of treatments, and making critical decisions regarding patient care.

For example, in stroke management, "time is brain," meaning that rapid intervention within a specific time frame (usually within 4.5 hours) is essential to administering tissue plasminogen activator (tPA), a clot-busting drug that can minimize brain damage and improve patient outcomes. Similarly, in trauma care, the "golden hour" concept emphasizes the importance of providing definitive care within the first 60 minutes after injury to increase survival rates and reduce morbidity.

Time factors also play a role in monitoring the progression of chronic conditions like diabetes or heart disease, where regular follow-ups and assessments help determine appropriate treatment adjustments and prevent complications. In infectious diseases, time factors are crucial for initiating antibiotic therapy and identifying potential outbreaks to control their spread.

Overall, "time factors" encompass the significance of recognizing and acting promptly in various medical scenarios to optimize patient outcomes and provide effective care.

Angiocardiography is a medical procedure used to examine the heart and blood vessels, particularly the chambers of the heart and the valves between them. It involves injecting a contrast agent into the bloodstream and taking X-ray images as the agent flows through the heart. This allows doctors to visualize any abnormalities such as blockages, narrowing, or leakage in the heart valves or blood vessels.

There are different types of angiocardiography, including:

* Left heart catheterization (LHC): A thin tube called a catheter is inserted into a vein in the arm or groin and threaded through to the left side of the heart to measure pressure and oxygen levels.
* Right heart catheterization (RHC): Similar to LHC, but the catheter is threaded through to the right side of the heart to measure pressure and oxygen levels there.
* Selective angiocardiography: A catheter is used to inject the contrast agent into specific blood vessels or chambers of the heart to get a more detailed view.

Angiocardiography can help diagnose and evaluate various heart conditions, including congenital heart defects, coronary artery disease, cardiomyopathy, and valvular heart disease. It is an invasive procedure that carries some risks, such as bleeding, infection, and damage to blood vessels or heart tissue. However, it can provide valuable information for diagnosing and treating heart conditions.

The Ductus Arteriosus is a fetal blood vessel that connects the pulmonary trunk (the artery that carries blood from the heart to the lungs) and the aorta (the largest artery in the body, which carries oxygenated blood from the heart to the rest of the body). This vessel allows most of the blood from the right ventricle of the fetal heart to bypass the lungs, as the fetus receives oxygen through the placenta rather than breathing air.

After birth, with the first breaths, the blood oxygen level increases and the pressure in the lungs rises. As a result, the circulation in the newborn's body changes, and the Ductus Arteriosus is no longer needed. Within the first few days or weeks of life, this vessel usually closes spontaneously, turning into a fibrous cord called the Ligamentum Arteriosum.

Persistent Patency of the Ductus Arteriosus (PDA) occurs when the Ductus Arteriosus does not close after birth, which can lead to various complications such as heart failure and pulmonary hypertension. This condition is often seen in premature infants and may require medical intervention or surgical closure of the vessel.

Mitral valve stenosis is a cardiac condition characterized by the narrowing or stiffening of the mitral valve, one of the four heart valves that regulate blood flow through the heart. This narrowing prevents the mitral valve from fully opening during diastole (relaxation phase of the heart cycle), leading to restricted flow of oxygenated blood from the left atrium into the left ventricle.

The narrowing or stiffening of the mitral valve can be caused by various factors, such as rheumatic heart disease, congenital heart defects, aging, or calcium deposits on the valve leaflets. As a result, the left atrium has to work harder to pump blood into the left ventricle, causing increased pressure in the left atrium and pulmonary veins. This can lead to symptoms such as shortness of breath, fatigue, coughing, and heart palpitations.

Mitral valve stenosis is typically diagnosed through a combination of medical history, physical examination, and imaging techniques like echocardiography or cardiac catheterization. Treatment options may include medications to manage symptoms and prevent complications, as well as surgical interventions such as mitral valve repair or replacement to alleviate the stenosis and improve heart function.

Cardiac catheterization is a medical procedure used to diagnose and treat cardiovascular conditions. In this procedure, a thin, flexible tube called a catheter is inserted into a blood vessel in the arm or leg and threaded up to the heart. The catheter can be used to perform various diagnostic tests, such as measuring the pressure inside the heart chambers and assessing the function of the heart valves.

Cardiac catheterization can also be used to treat certain cardiovascular conditions, such as narrowed or blocked arteries. In these cases, a balloon or stent may be inserted through the catheter to open up the blood vessel and improve blood flow. This procedure is known as angioplasty or percutaneous coronary intervention (PCI).

Cardiac catheterization is typically performed in a hospital cardiac catheterization laboratory by a team of healthcare professionals, including cardiologists, radiologists, and nurses. The procedure may be done under local anesthesia with sedation or general anesthesia, depending on the individual patient's needs and preferences.

Overall, cardiac catheterization is a valuable tool in the diagnosis and treatment of various heart conditions, and it can help improve symptoms, reduce complications, and prolong life for many patients.

Right atrial function refers to the role and performance of the right atrium in the heart. The right atrium is one of the four chambers of the heart and is responsible for receiving deoxygenated blood from the body via the superior and inferior vena cava. It then contracts to help pump the blood into the right ventricle, which subsequently sends it to the lungs for oxygenation.

Right atrial function can be assessed through various methods, including echocardiography, cardiac magnetic resonance imaging (MRI), and electrocardiogram (ECG). Abnormalities in right atrial function may indicate underlying heart conditions such as right-sided heart failure, atrial fibrillation, or other cardiovascular diseases. Proper evaluation and monitoring of right atrial function are essential for effective diagnosis, treatment, and management of these conditions.

The aortic valve is the valve located between the left ventricle (the lower left chamber of the heart) and the aorta (the largest artery in the body, which carries oxygenated blood from the heart to the rest of the body). It is made up of three thin flaps or leaflets that open and close to regulate blood flow. During a heartbeat, the aortic valve opens to allow blood to be pumped out of the left ventricle into the aorta, and then closes to prevent blood from flowing back into the ventricle when it relaxes. Any abnormality or damage to this valve can lead to various cardiovascular conditions such as aortic stenosis, aortic regurgitation, or infective endocarditis.

Papillary muscles are specialized muscle structures located in the heart, specifically in the ventricles (the lower chambers of the heart). They are attached to the tricuspid and mitral valves' leaflets via tendinous cords, also known as chordae tendineae. The main function of papillary muscles is to prevent the backflow of blood during contraction by providing tension to the valve leaflets through these tendinous cords.

There are two sets of papillary muscles in the heart:

1. Anterior and posterior papillary muscles in the left ventricle, which are attached to the mitral (bicuspid) valve.
2. Three smaller papillary muscles in the right ventricle, which are attached to the tricuspid valve.

These muscle structures play a crucial role in maintaining proper blood flow through the heart and ensuring efficient cardiac function.

A sarcomere is the basic contractile unit in a muscle fiber, and it's responsible for generating the force necessary for muscle contraction. It is composed of several proteins, including actin and myosin, which slide past each other to shorten the sarcomere during contraction. The sarcomere extends from one Z-line to the next in a muscle fiber, and it is delimited by the Z-discs where actin filaments are anchored. Sarcomeres play a crucial role in the functioning of skeletal, cardiac, and smooth muscles.

Artificial cardiac pacing is a medical procedure that involves the use of an artificial device to regulate and stimulate the contraction of the heart muscle. This is often necessary when the heart's natural pacemaker, the sinoatrial node, is not functioning properly and the heart is beating too slowly or irregularly.

The artificial pacemaker consists of a small generator that produces electrical impulses and leads that are positioned in the heart to transmit the impulses. The generator is typically implanted just under the skin in the chest, while the leads are inserted into the heart through a vein.

There are different types of artificial cardiac pacing systems, including single-chamber pacemakers, which stimulate either the right atrium or right ventricle, and dual-chamber pacemakers, which stimulate both chambers of the heart. Some pacemakers also have additional features that allow them to respond to changes in the body's needs, such as during exercise or sleep.

Artificial cardiac pacing is a safe and effective treatment for many people with abnormal heart rhythms, and it can significantly improve their quality of life and longevity.

Dilated cardiomyopathy (DCM) is a type of cardiomyopathy characterized by the enlargement and weakened contraction of the heart's main pumping chamber (the left ventricle). This enlargement and weakness can lead to symptoms such as shortness of breath, fatigue, and fluid retention. DCM can be caused by various factors including genetics, viral infections, alcohol and drug abuse, and other medical conditions like high blood pressure and diabetes. It is important to note that this condition can lead to heart failure if left untreated.

Three-dimensional echocardiography (3DE) is a type of cardiac ultrasound that uses advanced technologies to create a real-time, detailed 3D image of the heart. This imaging technique provides a more comprehensive view of the heart's structure and function compared to traditional 2D echocardiography. By visualizing the heart from multiple angles, 3DE can help physicians better assess complex cardiac conditions, plan treatments, and monitor their effectiveness.

In a 3DE examination, a transducer (a handheld device that emits and receives sound waves) is placed on the chest to capture ultrasound data. This data is then processed by specialized software to create a 3D model of the heart. The procedure is non-invasive and typically takes less than an hour to complete.

Three-dimensional echocardiography has several clinical applications, including:

1. Evaluation of cardiac morphology and function in congenital heart disease
2. Assessment of valvular structure and function, such as mitral or aortic valve regurgitation or stenosis
3. Guidance during interventional procedures like transcatheter aortic valve replacement (TAVR)
4. Quantification of left ventricular volumes, ejection fraction, and mass
5. Assessment of right ventricular size and function
6. Detection and monitoring of cardiac tumors or other masses
7. Pre-surgical planning for complex heart surgeries

Overall, 3DE offers a more accurate and detailed view of the heart, allowing healthcare providers to make informed decisions about patient care and improve outcomes.

The pulmonary valve, also known as the pulmonic valve, is a semilunar valve located at the exit of the right ventricle of the heart and the beginning of the pulmonary artery. It has three cusps or leaflets that prevent the backflow of blood from the pulmonary artery into the right ventricle during ventricular diastole, ensuring unidirectional flow of blood towards the lungs for oxygenation.

Right ventricular dysfunction is a condition characterized by the impaired ability of the right ventricle (one of the two pumping chambers in the heart) to fill with blood during the diastolic phase or eject blood during the systolic phase. This results in reduced cardiac output from the right ventricle, which can lead to various complications such as fluid accumulation in the body, particularly in the abdomen and lower extremities, and ultimately congestive heart failure if left untreated.

Right ventricular dysfunction can be caused by various factors, including damage to the heart muscle due to a heart attack, high blood pressure in the lungs (pulmonary hypertension), chronic lung diseases, congenital heart defects, viral infections, and certain medications. Symptoms of right ventricular dysfunction may include shortness of breath, fatigue, swelling in the legs, ankles, or abdomen, and a decreased tolerance for physical activity.

Diagnosis of right ventricular dysfunction typically involves a combination of medical history, physical examination, imaging tests such as echocardiography, cardiac MRI, or CT scan, and other diagnostic procedures such as electrocardiogram (ECG) or cardiac catheterization. Treatment options depend on the underlying cause but may include medications to reduce fluid buildup, improve heart function, and manage symptoms, as well as lifestyle modifications such as reducing salt intake and increasing physical activity levels. In severe cases, more invasive treatments such as surgery or implantable devices like pacemakers or ventricular assist devices may be necessary.

In medical terms, compliance refers to the degree to which a patient follows the recommendations or instructions of their healthcare provider. This may include taking prescribed medications as directed, following a treatment plan, making lifestyle changes, or attending follow-up appointments. Good compliance is essential for achieving the best possible health outcomes and can help prevent complications or worsening of medical conditions. Factors that can affect patient compliance include forgetfulness, lack of understanding of the instructions, cost of medications or treatments, and side effects of medications. Healthcare providers can take steps to improve patient compliance by providing clear and concise instructions, discussing potential barriers to compliance, and involving patients in their care plan.

Connectin is also known as titin, which is a giant protein that plays a crucial role in the elasticity and stiffness of muscle fibers. It is the largest protein in humans, spanning half the length of a muscle cell's sarcomere, the basic unit of muscle contraction. Connectin/titin has several domains with different functions, including binding to other proteins, regulating muscle contraction, and signaling within the muscle cell. Mutations in the connectin/titin gene have been associated with various forms of muscular dystrophy and cardiomyopathy.

Heart failure is a pathophysiological state in which the heart is unable to pump sufficient blood to meet the metabolic demands of the body or do so only at the expense of elevated filling pressures. It can be caused by various cardiac disorders, including coronary artery disease, hypertension, valvular heart disease, cardiomyopathy, and arrhythmias. Symptoms may include shortness of breath, fatigue, and fluid retention. Heart failure is often classified based on the ejection fraction (EF), which is the percentage of blood that is pumped out of the left ventricle during each contraction. A reduced EF (less than 40%) is indicative of heart failure with reduced ejection fraction (HFrEF), while a preserved EF (greater than or equal to 50%) is indicative of heart failure with preserved ejection fraction (HFpEF). There is also a category of heart failure with mid-range ejection fraction (HFmrEF) for those with an EF between 40-49%.

Constrictive pericarditis is a medical condition characterized by the inflammation and thickening of the pericardium, which is the sac-like membrane that surrounds the heart. This inflammation leads to scarring and thickening of the pericardium, causing it to become stiff and inflexible. As a result, the heart's ability to fill with blood between beats is restricted, leading to symptoms such as shortness of breath, fatigue, and fluid retention.

In contrastive pericarditis, the thickened and scarred pericardium restricts the normal movement of the heart within the chest cavity, leading to a characteristic pattern of hemodynamic abnormalities. These include equalization of diastolic pressures in all cardiac chambers, increased systemic venous pressure, and decreased cardiac output.

The most common causes of constrictive pericarditis include prior infection, radiation therapy, autoimmune disorders, and previous heart surgery. Diagnosis typically involves a combination of medical history, physical examination, imaging studies such as echocardiography or MRI, and sometimes invasive testing such as cardiac catheterization. Treatment may involve medications to manage symptoms and reduce inflammation, as well as surgical removal of the pericardium (pericardiectomy) in severe cases.

Reference values, also known as reference ranges or reference intervals, are the set of values that are considered normal or typical for a particular population or group of people. These values are often used in laboratory tests to help interpret test results and determine whether a patient's value falls within the expected range.

The process of establishing reference values typically involves measuring a particular biomarker or parameter in a large, healthy population and then calculating the mean and standard deviation of the measurements. Based on these statistics, a range is established that includes a certain percentage of the population (often 95%) and excludes extreme outliers.

It's important to note that reference values can vary depending on factors such as age, sex, race, and other demographic characteristics. Therefore, it's essential to use reference values that are specific to the relevant population when interpreting laboratory test results. Additionally, reference values may change over time due to advances in measurement technology or changes in the population being studied.

Cineangiography is a medical imaging technique used to visualize the blood flow in the heart and cardiovascular system. It involves the injection of a contrast agent into the bloodstream while X-ray images are taken in quick succession, creating a movie-like sequence that shows the movement of the contrast through the blood vessels and chambers of the heart. This technique is often used to diagnose and evaluate various heart conditions, such as coronary artery disease, valvular heart disease, and congenital heart defects.

The procedure typically involves threading a catheter through a blood vessel in the arm or leg and guiding it to the heart. Once in place, the contrast agent is injected, and X-ray images are taken using a specialized X-ray machine called a fluoroscope. The images captured during cineangiography can help doctors identify areas of narrowing or blockage in the coronary arteries, abnormalities in heart valves, and other cardiovascular problems.

Cineangiography is an invasive procedure that carries some risks, such as bleeding, infection, and reactions to the contrast agent. However, it can provide valuable information for diagnosing and treating heart conditions, and may be recommended when other diagnostic tests have been inconclusive.

Cardiac output is a measure of the amount of blood that is pumped by the heart in one minute. It is defined as the product of stroke volume (the amount of blood pumped by the left ventricle during each contraction) and heart rate (the number of contractions per minute). Normal cardiac output at rest for an average-sized adult is about 5 to 6 liters per minute. Cardiac output can be increased during exercise or other conditions that require more blood flow, such as during illness or injury. It can be measured noninvasively using techniques such as echocardiography or invasively through a catheter placed in the heart.

Vascular resistance is a measure of the opposition to blood flow within a vessel or a group of vessels, typically expressed in units of mmHg/(mL/min) or sometimes as dynes*sec/cm^5. It is determined by the diameter and length of the vessels, as well as the viscosity of the blood flowing through them. In general, a decrease in vessel diameter, an increase in vessel length, or an increase in blood viscosity will result in an increase in vascular resistance, while an increase in vessel diameter, a decrease in vessel length, or a decrease in blood viscosity will result in a decrease in vascular resistance. Vascular resistance is an important concept in the study of circulation and cardiovascular physiology because it plays a key role in determining blood pressure and blood flow within the body.

Regional blood flow (RBF) refers to the rate at which blood flows through a specific region or organ in the body, typically expressed in milliliters per minute per 100 grams of tissue (ml/min/100g). It is an essential physiological parameter that reflects the delivery of oxygen and nutrients to tissues while removing waste products. RBF can be affected by various factors such as metabolic demands, neural regulation, hormonal influences, and changes in blood pressure or vascular resistance. Measuring RBF is crucial for understanding organ function, diagnosing diseases, and evaluating the effectiveness of treatments.

Reproducibility of results in a medical context refers to the ability to obtain consistent and comparable findings when a particular experiment or study is repeated, either by the same researcher or by different researchers, following the same experimental protocol. It is an essential principle in scientific research that helps to ensure the validity and reliability of research findings.

In medical research, reproducibility of results is crucial for establishing the effectiveness and safety of new treatments, interventions, or diagnostic tools. It involves conducting well-designed studies with adequate sample sizes, appropriate statistical analyses, and transparent reporting of methods and findings to allow other researchers to replicate the study and confirm or refute the results.

The lack of reproducibility in medical research has become a significant concern in recent years, as several high-profile studies have failed to produce consistent findings when replicated by other researchers. This has led to increased scrutiny of research practices and a call for greater transparency, rigor, and standardization in the conduct and reporting of medical research.

In medical terms, pressure is defined as the force applied per unit area on an object or body surface. It is often measured in millimeters of mercury (mmHg) in clinical settings. For example, blood pressure is the force exerted by circulating blood on the walls of the arteries and is recorded as two numbers: systolic pressure (when the heart beats and pushes blood out) and diastolic pressure (when the heart rests between beats).

Pressure can also refer to the pressure exerted on a wound or incision to help control bleeding, or the pressure inside the skull or spinal canal. High or low pressure in different body systems can indicate various medical conditions and require appropriate treatment.

I apologize, but "sheep" is not a term that has a medical definition. It is a common animal with the scientific name Ovis aries. If you have any medical or health-related questions, I would be happy to try and help answer those for you.

The tricuspid valve is the heart valve that separates the right atrium and the right ventricle in the human heart. It is called "tricuspid" because it has three leaflets or cusps, which are also referred to as flaps or segments. These cusps are named anterior, posterior, and septal. The tricuspid valve's function is to prevent the backflow of blood from the ventricle into the atrium during systole, ensuring unidirectional flow of blood through the heart.

Mechanical stress, in the context of physiology and medicine, refers to any type of force that is applied to body tissues or organs, which can cause deformation or displacement of those structures. Mechanical stress can be either external, such as forces exerted on the body during physical activity or trauma, or internal, such as the pressure changes that occur within blood vessels or other hollow organs.

Mechanical stress can have a variety of effects on the body, depending on the type, duration, and magnitude of the force applied. For example, prolonged exposure to mechanical stress can lead to tissue damage, inflammation, and chronic pain. Additionally, abnormal or excessive mechanical stress can contribute to the development of various musculoskeletal disorders, such as tendinitis, osteoarthritis, and herniated discs.

In order to mitigate the negative effects of mechanical stress, the body has a number of adaptive responses that help to distribute forces more evenly across tissues and maintain structural integrity. These responses include changes in muscle tone, joint positioning, and connective tissue stiffness, as well as the remodeling of bone and other tissues over time. However, when these adaptive mechanisms are overwhelmed or impaired, mechanical stress can become a significant factor in the development of various pathological conditions.

Pulmonary wedge pressure, also known as pulmonary capillary wedge pressure (PCWP) or left heart filling pressure, is a measurement obtained during right heart catheterization. It reflects the pressure in the left atrium, which is an estimate of the diastolic pressure in the left ventricle. Normal PCWP ranges from 4 to 12 mmHg. Increased pulmonary wedge pressure can indicate heart failure or other cardiac disorders that affect the left side of the heart.

Transesophageal echocardiography (TEE) is a type of echocardiogram, which is a medical test that uses sound waves to create detailed images of the heart. In TEE, a special probe containing a transducer is passed down the esophagus (the tube that connects the mouth to the stomach) to obtain views of the heart from behind. This allows for more detailed images of the heart structures and function compared to a standard echocardiogram, which uses a probe placed on the chest. TEE is often used in patients with poor image quality from a standard echocardiogram or when more detailed images are needed to diagnose or monitor certain heart conditions. It is typically performed by a trained cardiologist or sonographer under the direction of a cardiologist.

Elasticity imaging techniques are non-invasive medical diagnostic methods used to evaluate the stiffness or elasticity of various tissues in the body, such as organs, muscles, and breast tissue. These techniques can help detect and diagnose abnormalities, including tumors, lesions, and other conditions that may affect tissue stiffness.

There are several types of elasticity imaging techniques, including:

1. Ultrasound Elastography: This technique uses ultrasound waves to apply pressure to tissues and measure their deformation or strain. The degree of deformation is then used to calculate the stiffness of the tissue.
2. Magnetic Resonance Elastography (MRE): MRE uses magnetic resonance imaging (MRI) to create images of tissue elasticity. A mechanical device is used to apply vibrations to the body, and the resulting motion is measured using MRI to determine tissue stiffness.
3. Shear Wave Elastography: This technique uses acoustic radiation force impulses to generate shear waves in tissues. The speed of these waves is then measured to calculate tissue stiffness.
4. Strain Imaging: This technique measures the amount of deformation or strain that occurs in tissues when they are compressed or stretched. It can be used to detect areas of increased stiffness, such as tumors or scar tissue.

Elasticity imaging techniques have several advantages over traditional diagnostic methods, including their non-invasive nature and ability to provide real-time images of tissue elasticity. They are also useful for monitoring changes in tissue stiffness over time, making them valuable tools for evaluating the effectiveness of treatments and monitoring disease progression.

Cardiac myocytes are the muscle cells that make up the heart muscle, also known as the myocardium. These specialized cells are responsible for contracting and relaxing in a coordinated manner to pump blood throughout the body. They differ from skeletal muscle cells in several ways, including their ability to generate their own electrical impulses, which allows the heart to function as an independent rhythmical pump. Cardiac myocytes contain sarcomeres, the contractile units of the muscle, and are connected to each other by intercalated discs that help coordinate contraction and ensure the synchronous beating of the heart.

The aorta is the largest artery in the human body, which originates from the left ventricle of the heart and carries oxygenated blood to the rest of the body. It can be divided into several parts, including the ascending aorta, aortic arch, and descending aorta. The ascending aorta gives rise to the coronary arteries that supply blood to the heart muscle. The aortic arch gives rise to the brachiocephalic, left common carotid, and left subclavian arteries, which supply blood to the head, neck, and upper extremities. The descending aorta travels through the thorax and abdomen, giving rise to various intercostal, visceral, and renal arteries that supply blood to the chest wall, organs, and kidneys.

Hypertrophic cardiomyopathy (HCM) is a genetic disorder characterized by the thickening of the heart muscle, specifically the ventricles (the lower chambers of the heart that pump blood out to the body). This thickening can make it harder for the heart to pump blood effectively, which can lead to symptoms such as shortness of breath, chest pain, and fatigue. In some cases, HCM can also cause abnormal heart rhythms (arrhythmias) and may increase the risk of sudden cardiac death.

The thickening of the heart muscle in HCM is caused by an overgrowth of the cells that make up the heart muscle, known as cardiomyocytes. This overgrowth can be caused by mutations in any one of several genes that encode proteins involved in the structure and function of the heart muscle. These genetic mutations are usually inherited from a parent, but they can also occur spontaneously in an individual with no family history of the disorder.

HCM is typically diagnosed using echocardiography (a type of ultrasound that uses sound waves to create images of the heart) and other diagnostic tests such as electrocardiogram (ECG) and cardiac magnetic resonance imaging (MRI). Treatment for HCM may include medications to help manage symptoms, lifestyle modifications, and in some cases, surgical procedures or implantable devices to help prevent or treat arrhythmias.

Tricuspid valve insufficiency, also known as tricuspid regurgitation, is a cardiac condition in which the tricuspid valve located between the right atrium and right ventricle of the heart does not close properly, allowing blood to flow back into the right atrium during contraction of the right ventricle. This results in a portion of the blood being pumped inefficiently, which can lead to volume overload of the right side of the heart and potentially result in symptoms such as fatigue, weakness, shortness of breath, and fluid retention. The condition can be congenital or acquired, with common causes including dilated cardiomyopathy, infective endocarditis, rheumatic heart disease, and trauma.

Computer-assisted image interpretation is the use of computer algorithms and software to assist healthcare professionals in analyzing and interpreting medical images. These systems use various techniques such as pattern recognition, machine learning, and artificial intelligence to help identify and highlight abnormalities or patterns within imaging data, such as X-rays, CT scans, MRI, and ultrasound images. The goal is to increase the accuracy, consistency, and efficiency of image interpretation, while also reducing the potential for human error. It's important to note that these systems are intended to assist healthcare professionals in their decision making process and not to replace them.

A pulse is a medical term that refers to the tactile sensation of the heartbeat that can be felt in various parts of the body, most commonly at the wrist, neck, or groin. It is caused by the surge of blood through an artery as the heart pushes blood out into the body during systole (contraction). The pulse can provide important information about a person's heart rate, rhythm, and strength, which are all crucial vital signs that help healthcare professionals assess a patient's overall health and identify any potential medical issues.

In summary, a pulse is a palpable manifestation of the heartbeat felt in an artery due to the ejection of blood by the heart during systole.

A myxoma is a type of benign (non-cancerous) tumor that develops in the heart, specifically in the heart's chambers or valves. It is the most common primary cardiac tumor in adults and typically affects the left atrium. Myxomas are composed of gelatinous, mucoid material and may have a stalk-like attachment to the endocardium (the inner lining of the heart).

Myxomas can vary in size and may cause symptoms such as shortness of breath, fatigue, chest pain, coughing, and fever. These symptoms are due to obstruction of blood flow within the heart or embolization (detachment and travel) of tumor fragments to other parts of the body. Surgical removal is usually required to treat myxomas, as they can lead to serious complications if left untreated.

Prenatal ultrasonography, also known as obstetric ultrasound, is a medical diagnostic procedure that uses high-frequency sound waves to create images of the developing fetus, placenta, and amniotic fluid inside the uterus. It is a non-invasive and painless test that is widely used during pregnancy to monitor the growth and development of the fetus, detect any potential abnormalities or complications, and determine the due date.

During the procedure, a transducer (a small handheld device) is placed on the mother's abdomen and moved around to capture images from different angles. The sound waves travel through the mother's body and bounce back off the fetus, producing echoes that are then converted into electrical signals and displayed as images on a screen.

Prenatal ultrasonography can be performed at various stages of pregnancy, including early pregnancy to confirm the pregnancy and detect the number of fetuses, mid-pregnancy to assess the growth and development of the fetus, and late pregnancy to evaluate the position of the fetus and determine if it is head down or breech. It can also be used to guide invasive procedures such as amniocentesis or chorionic villus sampling.

Overall, prenatal ultrasonography is a valuable tool in modern obstetrics that helps ensure the health and well-being of both the mother and the developing fetus.

Tetralogy of Fallot is a congenital heart defect that consists of four components: ventricular septal defect (a hole between the lower chambers of the heart), pulmonary stenosis (narrowing of the pulmonary valve and outflow tract), overriding aorta (the aorta lies directly over the ventricular septal defect), and right ventricular hypertrophy (thickening of the right ventricular muscle). This condition results in insufficient oxygenation of the blood, leading to cyanosis (bluish discoloration of the skin and mucous membranes) and other symptoms such as shortness of breath, fatigue, and poor growth. Treatment typically involves surgical repair, which is usually performed during infancy or early childhood.

In the context of medical terminology, "motion" generally refers to the act or process of moving or changing position. It can also refer to the range of movement of a body part or joint. However, there is no single specific medical definition for the term "motion." The meaning may vary depending on the context in which it is used.

Observer variation, also known as inter-observer variability or measurement agreement, refers to the difference in observations or measurements made by different observers or raters when evaluating the same subject or phenomenon. It is a common issue in various fields such as medicine, research, and quality control, where subjective assessments are involved.

In medical terms, observer variation can occur in various contexts, including:

1. Diagnostic tests: Different radiologists may interpret the same X-ray or MRI scan differently, leading to variations in diagnosis.
2. Clinical trials: Different researchers may have different interpretations of clinical outcomes or adverse events, affecting the consistency and reliability of trial results.
3. Medical records: Different healthcare providers may document medical histories, physical examinations, or treatment plans differently, leading to inconsistencies in patient care.
4. Pathology: Different pathologists may have varying interpretations of tissue samples or laboratory tests, affecting diagnostic accuracy.

Observer variation can be minimized through various methods, such as standardized assessment tools, training and calibration of observers, and statistical analysis of inter-rater reliability.

Computer-assisted image processing is a medical term that refers to the use of computer systems and specialized software to improve, analyze, and interpret medical images obtained through various imaging techniques such as X-ray, CT (computed tomography), MRI (magnetic resonance imaging), ultrasound, and others.

The process typically involves several steps, including image acquisition, enhancement, segmentation, restoration, and analysis. Image processing algorithms can be used to enhance the quality of medical images by adjusting contrast, brightness, and sharpness, as well as removing noise and artifacts that may interfere with accurate diagnosis. Segmentation techniques can be used to isolate specific regions or structures of interest within an image, allowing for more detailed analysis.

Computer-assisted image processing has numerous applications in medical imaging, including detection and characterization of lesions, tumors, and other abnormalities; assessment of organ function and morphology; and guidance of interventional procedures such as biopsies and surgeries. By automating and standardizing image analysis tasks, computer-assisted image processing can help to improve diagnostic accuracy, efficiency, and consistency, while reducing the potential for human error.

Pulmonary circulation refers to the process of blood flow through the lungs, where blood picks up oxygen and releases carbon dioxide. This is a vital part of the overall circulatory system, which delivers nutrients and oxygen to the body's cells while removing waste products like carbon dioxide.

In pulmonary circulation, deoxygenated blood from the systemic circulation returns to the right atrium of the heart via the superior and inferior vena cava. The blood then moves into the right ventricle through the tricuspid valve and gets pumped into the pulmonary artery when the right ventricle contracts.

The pulmonary artery divides into smaller vessels called arterioles, which further branch into a vast network of tiny capillaries in the lungs. Here, oxygen from the alveoli diffuses into the blood, binding to hemoglobin in red blood cells, while carbon dioxide leaves the blood and is exhaled through the nose or mouth.

The now oxygenated blood collects in venules, which merge to form pulmonary veins. These veins transport the oxygen-rich blood back to the left atrium of the heart, where it enters the systemic circulation once again. This continuous cycle enables the body's cells to receive the necessary oxygen and nutrients for proper functioning while disposing of waste products.

Cardiomyopathies are a group of diseases that affect the heart muscle, leading to mechanical and/or electrical dysfunction. The American Heart Association (AHA) defines cardiomyopathies as "a heterogeneous group of diseases of the myocardium associated with mechanical and/or electrical dysfunction that usually (but not always) exhibit inappropriate ventricular hypertrophy or dilatation and frequently lead to heart failure."

There are several types of cardiomyopathies, including:

1. Dilated cardiomyopathy (DCM): This is the most common type of cardiomyopathy, characterized by an enlarged left ventricle and impaired systolic function, leading to heart failure.
2. Hypertrophic cardiomyopathy (HCM): In this type, there is abnormal thickening of the heart muscle, particularly in the septum between the two ventricles, which can obstruct blood flow and increase the risk of arrhythmias.
3. Restrictive cardiomyopathy (RCM): This is a rare form of cardiomyopathy characterized by stiffness of the heart muscle, impaired relaxation, and diastolic dysfunction, leading to reduced filling of the ventricles and heart failure.
4. Arrhythmogenic right ventricular cardiomyopathy (ARVC): In this type, there is replacement of the normal heart muscle with fatty or fibrous tissue, primarily affecting the right ventricle, which can lead to arrhythmias and sudden cardiac death.
5. Unclassified cardiomyopathies: These are conditions that do not fit into any of the above categories but still significantly affect the heart muscle and function.

Cardiomyopathies can be caused by genetic factors, acquired conditions (e.g., infections, toxins, or autoimmune disorders), or a combination of both. The diagnosis typically involves a comprehensive evaluation, including medical history, physical examination, electrocardiogram (ECG), echocardiography, cardiac magnetic resonance imaging (MRI), and sometimes genetic testing. Treatment depends on the type and severity of the condition but may include medications, lifestyle modifications, implantable devices, or even heart transplantation in severe cases.

Perfusion, in medical terms, refers to the process of circulating blood through the body's organs and tissues to deliver oxygen and nutrients and remove waste products. It is a measure of the delivery of adequate blood flow to specific areas or tissues in the body. Perfusion can be assessed using various methods, including imaging techniques like computed tomography (CT) scans, magnetic resonance imaging (MRI), and perfusion scintigraphy.

Perfusion is critical for maintaining proper organ function and overall health. When perfusion is impaired or inadequate, it can lead to tissue hypoxia, acidosis, and cell death, which can result in organ dysfunction or failure. Conditions that can affect perfusion include cardiovascular disease, shock, trauma, and certain surgical procedures.

Biomechanics is the application of mechanical laws to living structures and systems, particularly in the field of medicine and healthcare. A biomechanical phenomenon refers to a observable event or occurrence that involves the interaction of biological tissues or systems with mechanical forces. These phenomena can be studied at various levels, from the molecular and cellular level to the tissue, organ, and whole-body level.

Examples of biomechanical phenomena include:

1. The way that bones and muscles work together to produce movement (known as joint kinematics).
2. The mechanical behavior of biological tissues such as bone, cartilage, tendons, and ligaments under various loads and stresses.
3. The response of cells and tissues to mechanical stimuli, such as the way that bone tissue adapts to changes in loading conditions (known as Wolff's law).
4. The biomechanics of injury and disease processes, such as the mechanisms of joint injury or the development of osteoarthritis.
5. The use of mechanical devices and interventions to treat medical conditions, such as orthopedic implants or assistive devices for mobility impairments.

Understanding biomechanical phenomena is essential for developing effective treatments and prevention strategies for a wide range of medical conditions, from musculoskeletal injuries to neurological disorders.

Cardiomegaly is a medical term that refers to an enlarged heart. It can be caused by various conditions such as high blood pressure, heart valve problems, cardiomyopathy, or fluid accumulation around the heart (pericardial effusion). Cardiomegaly can be detected through imaging tests like chest X-rays or echocardiograms. Depending on the underlying cause, treatment options may include medications, lifestyle changes, or in some cases, surgery. It is important to consult with a healthcare professional for proper diagnosis and treatment.

A heart valve prosthesis is a medical device that is implanted in the heart to replace a damaged or malfunctioning heart valve. The prosthetic valve can be made of biological tissue (such as from a pig or cow) or artificial materials (such as carbon or polyester). Its function is to allow for the proper directional flow of blood through the heart, opening and closing with each heartbeat to prevent backflow of blood.

There are several types of heart valve prostheses, including:

1. Mechanical valves: These are made entirely of artificial materials and have a longer lifespan than biological valves. However, they require the patient to take blood-thinning medication for the rest of their life to prevent blood clots from forming on the valve.
2. Bioprosthetic valves: These are made of biological tissue and typically last 10-15 years before needing replacement. They do not require the patient to take blood-thinning medication, but there is a higher risk of reoperation due to degeneration of the tissue over time.
3. Homografts or allografts: These are human heart valves that have been donated and preserved for transplantation. They have similar longevity to bioprosthetic valves and do not require blood-thinning medication.
4. Autografts: In this case, the patient's own pulmonary valve is removed and used to replace the damaged aortic valve. This procedure is called the Ross procedure and has excellent long-term results, but it requires advanced surgical skills and is not widely available.

The choice of heart valve prosthesis depends on various factors, including the patient's age, overall health, lifestyle, and personal preferences.

Blood volume refers to the total amount of blood present in an individual's circulatory system at any given time. It is the combined volume of both the plasma (the liquid component of blood) and the formed elements (such as red and white blood cells and platelets) in the blood. In a healthy adult human, the average blood volume is approximately 5 liters (or about 1 gallon). However, blood volume can vary depending on several factors, including age, sex, body weight, and overall health status.

Blood volume plays a critical role in maintaining proper cardiovascular function, as it affects blood pressure, heart rate, and the delivery of oxygen and nutrients to tissues throughout the body. Changes in blood volume can have significant impacts on an individual's health and may be associated with various medical conditions, such as dehydration, hemorrhage, heart failure, and liver disease. Accurate measurement of blood volume is essential for diagnosing and managing these conditions, as well as for guiding treatment decisions in clinical settings.

Arteries are blood vessels that carry oxygenated blood away from the heart to the rest of the body. They have thick, muscular walls that can withstand the high pressure of blood being pumped out of the heart. Arteries branch off into smaller vessels called arterioles, which further divide into a vast network of tiny capillaries where the exchange of oxygen, nutrients, and waste occurs between the blood and the body's cells. After passing through the capillary network, deoxygenated blood collects in venules, then merges into veins, which return the blood back to the heart.

The sarcoplasmic reticulum (SR) is a specialized type of smooth endoplasmic reticulum found in muscle cells, particularly in striated muscles such as skeletal and cardiac muscles. It is a complex network of tubules that surrounds the myofibrils, the contractile elements of the muscle fiber.

The primary function of the sarcoplasmic reticulum is to store calcium ions (Ca2+) and regulate their release during muscle contraction and uptake during muscle relaxation. The SR contains a high concentration of calcium-binding proteins, such as calsequestrin, which help to maintain this storage.

The release of calcium ions from the sarcoplasmic reticulum is triggered by an action potential that travels along the muscle fiber's sarcolemma and into the muscle fiber's interior (the sarcoplasm). This action potential causes the voltage-gated calcium channels in the SR membrane, known as ryanodine receptors, to open, releasing Ca2+ ions into the sarcoplasm.

The increased concentration of Ca2+ ions in the sarcoplasm triggers muscle contraction by binding to troponin, a protein associated with actin filaments, causing a conformational change that exposes the active sites on actin for myosin heads to bind and generate force.

After muscle contraction, the calcium ions must be actively transported back into the sarcoplasmic reticulum by Ca2+ ATPase pumps, also known as sarco(endo)plasmic reticulum calcium ATPases (SERCAs). This process helps to lower the concentration of Ca2+ in the sarcoplasm and allows the muscle fiber to relax.

Overall, the sarcoplasmic reticulum plays a crucial role in excitation-contraction coupling, the process by which action potentials trigger muscle contraction.

Pathologic dilatation refers to an abnormal and excessive widening or enlargement of a body cavity or organ, which can result from various medical conditions. This abnormal dilation can occur in different parts of the body, including the blood vessels, digestive tract, airways, or heart chambers.

In the context of the cardiovascular system, pathologic dilatation may indicate a weakening or thinning of the heart muscle, leading to an enlarged chamber that can no longer pump blood efficiently. This condition is often associated with various heart diseases, such as cardiomyopathy, valvular heart disease, or long-standing high blood pressure.

In the gastrointestinal tract, pathologic dilatation may occur due to mechanical obstruction, neuromuscular disorders, or inflammatory conditions that affect the normal motility of the intestines. Examples include megacolon in Hirschsprung's disease, toxic megacolon in ulcerative colitis, or volvulus (twisting) of the bowel.

Pathologic dilatation can lead to various complications, such as reduced organ function, impaired circulation, and increased risk of infection or perforation. Treatment depends on the underlying cause and may involve medications, surgery, or other interventions to address the root problem and prevent further enlargement.

Laser-Doppler flowmetry (LDF) is a non-invasive, investigative technique used to measure microcirculatory blood flow in real time. It is based on the principle of the Doppler effect, which describes the change in frequency or wavelength of light or sound waves as they encounter a moving object or reflect off a moving surface.

In LDF, a low-power laser beam is directed at the skin or other transparent tissue. The light penetrates the tissue and scatters off the moving red blood cells within the microvasculature. As the light scatters, it undergoes a slight frequency shift due to the movement of the red blood cells. This frequency shift is then detected by a photodetector, which converts it into an electrical signal. The magnitude of this signal is directly proportional to the speed and concentration of the moving red blood cells, providing a measure of microcirculatory blood flow.

LDF has various clinical applications, including the assessment of skin perfusion in patients with peripheral arterial disease, burn injuries, and flaps used in reconstructive surgery. It can also be used to study the effects of drugs or other interventions on microcirculation in research settings.

Medical Definition:

Magnetic Resonance Imaging (MRI) is a non-invasive diagnostic imaging technique that uses a strong magnetic field and radio waves to create detailed cross-sectional or three-dimensional images of the internal structures of the body. The patient lies within a large, cylindrical magnet, and the scanner detects changes in the direction of the magnetic field caused by protons in the body. These changes are then converted into detailed images that help medical professionals to diagnose and monitor various medical conditions, such as tumors, injuries, or diseases affecting the brain, spinal cord, heart, blood vessels, joints, and other internal organs. MRI does not use radiation like computed tomography (CT) scans.

Prospective studies, also known as longitudinal studies, are a type of cohort study in which data is collected forward in time, following a group of individuals who share a common characteristic or exposure over a period of time. The researchers clearly define the study population and exposure of interest at the beginning of the study and follow up with the participants to determine the outcomes that develop over time. This type of study design allows for the investigation of causal relationships between exposures and outcomes, as well as the identification of risk factors and the estimation of disease incidence rates. Prospective studies are particularly useful in epidemiology and medical research when studying diseases with long latency periods or rare outcomes.

An action potential is a brief electrical signal that travels along the membrane of a nerve cell (neuron) or muscle cell. It is initiated by a rapid, localized change in the permeability of the cell membrane to specific ions, such as sodium and potassium, resulting in a rapid influx of sodium ions and a subsequent efflux of potassium ions. This ion movement causes a brief reversal of the electrical potential across the membrane, which is known as depolarization. The action potential then propagates along the cell membrane as a wave, allowing the electrical signal to be transmitted over long distances within the body. Action potentials play a crucial role in the communication and functioning of the nervous system and muscle tissue.

The pulmonary artery is a large blood vessel that carries deoxygenated blood from the right ventricle of the heart to the lungs for oxygenation. It divides into two main branches, the right and left pulmonary arteries, which further divide into smaller vessels called arterioles, and then into a vast network of capillaries in the lungs where gas exchange occurs. The thin walls of these capillaries allow oxygen to diffuse into the blood and carbon dioxide to diffuse out, making the blood oxygen-rich before it is pumped back to the left side of the heart through the pulmonary veins. This process is crucial for maintaining proper oxygenation of the body's tissues and organs.

Calcium is an essential mineral that is vital for various physiological processes in the human body. The medical definition of calcium is as follows:

Calcium (Ca2+) is a crucial cation and the most abundant mineral in the human body, with approximately 99% of it found in bones and teeth. It plays a vital role in maintaining structural integrity, nerve impulse transmission, muscle contraction, hormonal secretion, blood coagulation, and enzyme activation.

Calcium homeostasis is tightly regulated through the interplay of several hormones, including parathyroid hormone (PTH), calcitonin, and vitamin D. Dietary calcium intake, absorption, and excretion are also critical factors in maintaining optimal calcium levels in the body.

Hypocalcemia refers to low serum calcium levels, while hypercalcemia indicates high serum calcium levels. Both conditions can have detrimental effects on various organ systems and require medical intervention to correct.

Myocardial ischemia is a condition in which the blood supply to the heart muscle (myocardium) is reduced or blocked, leading to insufficient oxygen delivery and potential damage to the heart tissue. This reduction in blood flow typically results from the buildup of fatty deposits, called plaques, in the coronary arteries that supply the heart with oxygen-rich blood. The plaques can rupture or become unstable, causing the formation of blood clots that obstruct the artery and limit blood flow.

Myocardial ischemia may manifest as chest pain (angina pectoris), shortness of breath, fatigue, or irregular heartbeats (arrhythmias). In severe cases, it can lead to myocardial infarction (heart attack) if the oxygen supply is significantly reduced or cut off completely, causing permanent damage or death of the heart muscle. Early diagnosis and treatment of myocardial ischemia are crucial for preventing further complications and improving patient outcomes.

Coronary artery disease, often simply referred to as coronary disease, is a condition in which the blood vessels that supply oxygen-rich blood to the heart become narrowed or blocked due to the buildup of fatty deposits called plaques. This can lead to chest pain (angina), shortness of breath, or in severe cases, a heart attack.

The medical definition of coronary artery disease is:

A condition characterized by the accumulation of atheromatous plaques in the walls of the coronary arteries, leading to decreased blood flow and oxygen supply to the myocardium (heart muscle). This can result in symptoms such as angina pectoris, shortness of breath, or arrhythmias, and may ultimately lead to myocardial infarction (heart attack) or heart failure.

Risk factors for coronary artery disease include age, smoking, high blood pressure, high cholesterol, diabetes, obesity, physical inactivity, and a family history of the condition. Lifestyle changes such as quitting smoking, exercising regularly, eating a healthy diet, and managing stress can help reduce the risk of developing coronary artery disease. Medical treatments may include medications to control blood pressure, cholesterol levels, or irregular heart rhythms, as well as procedures such as angioplasty or bypass surgery to improve blood flow to the heart.

Hyperemia is a medical term that refers to an increased flow or accumulation of blood in certain capillaries or vessels within an organ or tissue, resulting in its redness and warmth. This can occur due to various reasons such as physical exertion, emotional excitement, local injury, or specific medical conditions.

There are two types of hyperemia: active and passive. Active hyperemia is a physiological response where the blood flow increases as a result of the metabolic demands of the organ or tissue. For example, during exercise, muscles require more oxygen and nutrients, leading to an increase in blood flow. Passive hyperemia, on the other hand, occurs when there is a blockage in the venous outflow, causing the blood to accumulate in the affected area. This can result from conditions like thrombosis or vasoconstriction.

It's important to note that while hyperemia itself is not a disease, it can be a symptom of various underlying medical conditions and should be evaluated by a healthcare professional if it persists or is accompanied by other symptoms.

Coronary angiography is a medical procedure that uses X-ray imaging to visualize the coronary arteries, which supply blood to the heart muscle. During the procedure, a thin, flexible catheter is inserted into an artery in the arm or groin and threaded through the blood vessels to the heart. A contrast dye is then injected through the catheter, and X-ray images are taken as the dye flows through the coronary arteries. These images can help doctors diagnose and treat various heart conditions, such as blockages or narrowing of the arteries, that can lead to chest pain or heart attacks. It is also known as coronary arteriography or cardiac catheterization.

Heart neoplasms are abnormal growths or tumors that develop within the heart tissue. They can be benign (noncancerous) or malignant (cancerous). Benign tumors, such as myxomas and rhabdomyomas, are typically slower growing and less likely to spread, but they can still cause serious complications if they obstruct blood flow or damage heart valves. Malignant tumors, such as angiosarcomas and rhabdomyosarcomas, are fast-growing and have a higher risk of spreading to other parts of the body. Symptoms of heart neoplasms can include shortness of breath, chest pain, fatigue, and irregular heart rhythms. Treatment options depend on the type, size, and location of the tumor, and may include surgery, radiation therapy, or chemotherapy.

Coronary stenosis is a medical condition that refers to the narrowing of the coronary arteries, which supply oxygen-rich blood to the heart muscle. This narrowing is typically caused by the buildup of plaque, made up of fat, cholesterol, and other substances, on the inner walls of the arteries. Over time, as the plaque hardens and calcifies, it can cause the artery to become narrowed or blocked, reducing blood flow to the heart muscle.

Coronary stenosis can lead to various symptoms and complications, including chest pain (angina), shortness of breath, irregular heart rhythms (arrhythmias), and heart attacks. Treatment options for coronary stenosis may include lifestyle changes, medications, medical procedures such as angioplasty or bypass surgery, or a combination of these approaches. Regular check-ups and diagnostic tests, such as stress testing or coronary angiography, can help detect and monitor coronary stenosis over time.

Ultrasonography, Doppler refers to a non-invasive diagnostic medical procedure that uses high-frequency sound waves to create real-time images of the movement of blood flow through vessels, tissues, or heart valves. The Doppler effect is used to measure the frequency shift of the ultrasound waves as they bounce off moving red blood cells, which allows for the calculation of the speed and direction of blood flow. This technique is commonly used to diagnose and monitor various conditions such as deep vein thrombosis, carotid artery stenosis, heart valve abnormalities, and fetal heart development during pregnancy. It does not use radiation or contrast agents and is considered safe with minimal risks.

Ventricular remodeling is a structural adaptation process of the heart in response to stress or injury, such as myocardial infarction (heart attack) or pressure overload. This process involves changes in size, shape, and function of the ventricles (the lower chambers of the heart).

In ventricular remodeling, the heart muscle may thicken, enlarge, or become more stiff, leading to alterations in the pumping ability of the heart. These changes can ultimately result in cardiac dysfunction, heart failure, and an increased risk of arrhythmias (irregular heart rhythms).

Ventricular remodeling is often classified into two types:

1. Concentric remodeling: This occurs when the ventricular wall thickens (hypertrophy) without a significant increase in chamber size, leading to a decrease in the cavity volume and an increase in the thickness of the ventricular wall.
2. Eccentric remodeling: This involves an increase in both the ventricular chamber size and wall thickness due to the addition of new muscle cells (hyperplasia) or enlargement of existing muscle cells (hypertrophy). As a result, the overall shape of the ventricle becomes more spherical and less elliptical.

Both types of remodeling can negatively impact heart function and contribute to the development of heart failure. Close monitoring and appropriate treatment are essential for managing ventricular remodeling and preventing further complications.

The heart conduction system is a group of specialized cardiac muscle cells that generate and conduct electrical impulses to coordinate the contraction of the heart chambers. The main components of the heart conduction system include:

1. Sinoatrial (SA) node: Also known as the sinus node, it is located in the right atrium near the entrance of the superior vena cava and functions as the primary pacemaker of the heart. It sets the heart rate by generating electrical impulses at regular intervals.
2. Atrioventricular (AV) node: Located in the interatrial septum, near the opening of the coronary sinus, it serves as a relay station for electrical signals between the atria and ventricles. The AV node delays the transmission of impulses to allow the atria to contract before the ventricles.
3. Bundle of His: A bundle of specialized cardiac muscle fibers that conducts electrical impulses from the AV node to the ventricles. It divides into two main branches, the right and left bundle branches, which further divide into smaller Purkinje fibers.
4. Right and left bundle branches: These are extensions of the Bundle of His that transmit electrical impulses to the respective right and left ventricular myocardium. They consist of specialized conducting tissue with large diameters and minimal resistance, allowing for rapid conduction of electrical signals.
5. Purkinje fibers: Fine, branching fibers that arise from the bundle branches and spread throughout the ventricular myocardium. They are responsible for transmitting electrical impulses to the working cardiac muscle cells, triggering coordinated ventricular contraction.

In summary, the heart conduction system is a complex network of specialized muscle cells responsible for generating and conducting electrical signals that coordinate the contraction of the atria and ventricles, ensuring efficient blood flow throughout the body.

The Ryanodine Receptor (RyR) is a calcium release channel located on the sarcoplasmic reticulum (SR), a type of endoplasmic reticulum found in muscle cells. It plays a crucial role in excitation-contraction coupling, which is the process by which electrical signals are converted into mechanical responses in muscle fibers.

In more detail, when an action potential reaches the muscle fiber's surface membrane, it triggers the opening of voltage-gated L-type calcium channels (Dihydropyridine Receptors or DHPRs) in the sarcolemma (the cell membrane of muscle fibers). This influx of calcium ions into the cytoplasm causes a conformational change in the RyR, leading to its own opening and the release of stored calcium from the SR into the cytoplasm. The increased cytoplasmic calcium concentration then initiates muscle contraction through interaction with contractile proteins like actin and myosin.

There are three isoforms of RyR: RyR1, RyR2, and RyR3. RyR1 is primarily found in skeletal muscle, while RyR2 is predominantly expressed in cardiac muscle. Both RyR1 and RyR2 are large homotetrameric proteins with a molecular weight of approximately 2.2 million Daltons. They contain multiple domains including an ion channel pore, regulatory domains, and a foot structure that interacts with DHPRs. RyR3 is more widely distributed, being found in various tissues such as the brain, smooth muscle, and some types of neurons.

Dysfunction of these channels has been implicated in several diseases including malignant hyperthermia, central core disease, catecholaminergic polymorphic ventricular tachycardia (CPVT), and certain forms of heart failure.

Hypertension is a medical term used to describe abnormally high blood pressure in the arteries, often defined as consistently having systolic blood pressure (the top number in a blood pressure reading) over 130 mmHg and/or diastolic blood pressure (the bottom number) over 80 mmHg. It is also commonly referred to as high blood pressure.

Hypertension can be classified into two types: primary or essential hypertension, which has no identifiable cause and accounts for about 95% of cases, and secondary hypertension, which is caused by underlying medical conditions such as kidney disease, hormonal disorders, or use of certain medications.

If left untreated, hypertension can lead to serious health complications such as heart attack, stroke, heart failure, and chronic kidney disease. Therefore, it is important for individuals with hypertension to manage their condition through lifestyle modifications (such as healthy diet, regular exercise, stress management) and medication if necessary, under the guidance of a healthcare professional.

Cardiac arrhythmias are abnormal heart rhythms that result from disturbances in the electrical conduction system of the heart. The heart's normal rhythm is controlled by an electrical signal that originates in the sinoatrial (SA) node, located in the right atrium. This signal travels through the atrioventricular (AV) node and into the ventricles, causing them to contract and pump blood throughout the body.

An arrhythmia occurs when there is a disruption in this electrical pathway or when the heart's natural pacemaker produces an abnormal rhythm. This can cause the heart to beat too fast (tachycardia), too slow (bradycardia), or irregularly.

There are several types of cardiac arrhythmias, including:

1. Atrial fibrillation: A rapid and irregular heartbeat that starts in the atria (the upper chambers of the heart).
2. Atrial flutter: A rapid but regular heartbeat that starts in the atria.
3. Supraventricular tachycardia (SVT): A rapid heartbeat that starts above the ventricles, usually in the atria or AV node.
4. Ventricular tachycardia: A rapid and potentially life-threatening heart rhythm that originates in the ventricles.
5. Ventricular fibrillation: A chaotic and disorganized electrical activity in the ventricles, which can be fatal if not treated immediately.
6. Heart block: A delay or interruption in the conduction of electrical signals from the atria to the ventricles.

Cardiac arrhythmias can cause various symptoms, such as palpitations, dizziness, shortness of breath, chest pain, and fatigue. In some cases, they may not cause any symptoms and go unnoticed. However, if left untreated, certain types of arrhythmias can lead to serious complications, including stroke, heart failure, or even sudden cardiac death.

Treatment for cardiac arrhythmias depends on the type, severity, and underlying causes. Options may include lifestyle changes, medications, cardioversion (electrical shock therapy), catheter ablation, implantable devices such as pacemakers or defibrillators, and surgery. It is essential to consult a healthcare professional for proper evaluation and management of cardiac arrhythmias.

Dobutamine is a synthetic catecholamine used in medical treatment, specifically as a positive inotrope and vasodilator. It works by stimulating the beta-1 adrenergic receptors of the heart, thereby increasing its contractility and stroke volume. This results in an improved cardiac output, making dobutamine beneficial in treating heart failure, cardiogenic shock, and other conditions where heart function is compromised.

It's important to note that dobutamine should be administered under strict medical supervision due to its potential to cause adverse effects such as arrhythmias, hypotension, or hypertension. The dosage, frequency, and duration of administration are determined by the patient's specific condition and response to treatment.

The Predictive Value of Tests, specifically the Positive Predictive Value (PPV) and Negative Predictive Value (NPV), are measures used in diagnostic tests to determine the probability that a positive or negative test result is correct.

Positive Predictive Value (PPV) is the proportion of patients with a positive test result who actually have the disease. It is calculated as the number of true positives divided by the total number of positive results (true positives + false positives). A higher PPV indicates that a positive test result is more likely to be a true positive, and therefore the disease is more likely to be present.

Negative Predictive Value (NPV) is the proportion of patients with a negative test result who do not have the disease. It is calculated as the number of true negatives divided by the total number of negative results (true negatives + false negatives). A higher NPV indicates that a negative test result is more likely to be a true negative, and therefore the disease is less likely to be present.

The predictive value of tests depends on the prevalence of the disease in the population being tested, as well as the sensitivity and specificity of the test. A test with high sensitivity and specificity will generally have higher predictive values than a test with low sensitivity and specificity. However, even a highly sensitive and specific test can have low predictive values if the prevalence of the disease is low in the population being tested.

Gestational age is the length of time that has passed since the first day of the last menstrual period (LMP) in pregnant women. It is the standard unit used to estimate the age of a pregnancy and is typically expressed in weeks. This measure is used because the exact date of conception is often not known, but the start of the last menstrual period is usually easier to recall.

It's important to note that since ovulation typically occurs around two weeks after the start of the LMP, gestational age is approximately two weeks longer than fetal age, which is the actual time elapsed since conception. Medical professionals use both gestational and fetal age to track the development and growth of the fetus during pregnancy.

Heart-assist devices, also known as mechanical circulatory support devices, are medical equipment designed to help the heart function more efficiently. These devices can be used in patients with advanced heart failure who are not responding to medication or other treatments. They work by taking over some or all of the heart's pumping functions, reducing the workload on the heart and improving blood flow to the rest of the body.

There are several types of heart-assist devices, including:

1. Intra-aortic balloon pumps (IABPs): These devices are inserted into the aorta, the large artery that carries blood from the heart to the rest of the body. The IABP inflates and deflates in time with the heartbeat, helping to improve blood flow to the coronary arteries and reduce the workload on the heart.
2. Ventricular assist devices (VADs): These devices are more invasive than IABPs and are used to support the function of one or both ventricles, the lower chambers of the heart. VADs can be used to support the heart temporarily while a patient recovers from surgery or heart failure, or they can be used as a long-term solution for patients who are not candidates for a heart transplant.
3. Total artificial hearts (TAHs): These devices replace both ventricles and all four valves of the heart. TAHs are used in patients who are not candidates for a heart transplant and have severe biventricular failure, meaning that both ventricles are no longer functioning properly.

Heart-assist devices can be life-saving for some patients with advanced heart failure, but they also carry risks, such as infection, bleeding, and device malfunction. As with any medical treatment, the benefits and risks of using a heart-assist device must be carefully weighed for each individual patient.

Regression analysis is a statistical technique used in medicine, as well as in other fields, to examine the relationship between one or more independent variables (predictors) and a dependent variable (outcome). It allows for the estimation of the average change in the outcome variable associated with a one-unit change in an independent variable, while controlling for the effects of other independent variables. This technique is often used to identify risk factors for diseases or to evaluate the effectiveness of medical interventions. In medical research, regression analysis can be used to adjust for potential confounding variables and to quantify the relationship between exposures and health outcomes. It can also be used in predictive modeling to estimate the probability of a particular outcome based on multiple predictors.

Sensitivity and specificity are statistical measures used to describe the performance of a diagnostic test or screening tool in identifying true positive and true negative results.

* Sensitivity refers to the proportion of people who have a particular condition (true positives) who are correctly identified by the test. It is also known as the "true positive rate" or "recall." A highly sensitive test will identify most or all of the people with the condition, but may also produce more false positives.
* Specificity refers to the proportion of people who do not have a particular condition (true negatives) who are correctly identified by the test. It is also known as the "true negative rate." A highly specific test will identify most or all of the people without the condition, but may also produce more false negatives.

In medical testing, both sensitivity and specificity are important considerations when evaluating a diagnostic test. High sensitivity is desirable for screening tests that aim to identify as many cases of a condition as possible, while high specificity is desirable for confirmatory tests that aim to rule out the condition in people who do not have it.

It's worth noting that sensitivity and specificity are often influenced by factors such as the prevalence of the condition in the population being tested, the threshold used to define a positive result, and the reliability and validity of the test itself. Therefore, it's important to consider these factors when interpreting the results of a diagnostic test.

I believe there may be some confusion in your question. "Rabbits" is a common name used to refer to the Lagomorpha species, particularly members of the family Leporidae. They are small mammals known for their long ears, strong legs, and quick reproduction.

However, if you're referring to "rabbits" in a medical context, there is a term called "rabbit syndrome," which is a rare movement disorder characterized by repetitive, involuntary movements of the fingers, resembling those of a rabbit chewing. It is also known as "finger-chewing chorea." This condition is usually associated with certain medications, particularly antipsychotics, and typically resolves when the medication is stopped or adjusted.

Aging is a complex, progressive and inevitable process of bodily changes over time, characterized by the accumulation of cellular damage and degenerative changes that eventually lead to increased vulnerability to disease and death. It involves various biological, genetic, environmental, and lifestyle factors that contribute to the decline in physical and mental functions. The medical field studies aging through the discipline of gerontology, which aims to understand the underlying mechanisms of aging and develop interventions to promote healthy aging and extend the human healthspan.

I'm sorry for any confusion, but "Linear Models" is actually a term from the field of statistics and machine learning, rather than medicine. A linear model is a type of statistical model that is used to analyze the relationship between two or more variables. In a linear model, the relationship between the dependent variable (the outcome or result) and the independent variable(s) (the factors being studied) is assumed to be linear, meaning that it can be described by a straight line on a graph.

The equation for a simple linear model with one independent variable (x) and one dependent variable (y) looks like this:

y = β0 + β1*x + ε

In this equation, β0 is the y-intercept or the value of y when x equals zero, β1 is the slope or the change in y for each unit increase in x, and ε is the error term or the difference between the actual values of y and the predicted values of y based on the linear model.

Linear models are widely used in medical research to study the relationship between various factors (such as exposure to a risk factor or treatment) and health outcomes (such as disease incidence or mortality). They can also be used to adjust for confounding variables, which are factors that may influence both the independent variable and the dependent variable, and thus affect the observed relationship between them.

Atrial diastole is the relaxing of the atria, and ventricular diastole the relaxing of the ventricles. The term originates from ... Early diastole is a suction mechanism between the atrial and ventricular chambers. Then, in late ventricular diastole, the two ... Sabbah, H. N.; Stein, P. D. (1981). "Pressure-diameter relations during early diastole in dogs. The role of suction in Diastole ... Diastole (/daɪˈæstəli/ dy-AST-ə-lee) is the relaxed phase of the cardiac cycle when the chambers of the heart are re-filling ...
Species in the genus Diastole include: [1] Diastole bryani H. B. Baker, 1938 Diastole conula (Pease, 1861) Diastole exposita ( ... Diastole futunae H. B. Baker, 1938 Diastole glaucina Baker, 1938 Diastole lamellaxis Baker, 1938 Diastole lauae H. B. Baker, ... 1938 Diastole rurutui H. B. Baker, 1938 Diastole savaii Baker, 1938 Diastole schmeltziana (Mousson, 1865) Diastole simonei ... Thach & F. Huber, 2017 (taxon inquirendum) Diastole subcarinata Solem, 1959 Diastole tenuistriata Preece, 1995 Diastole tongana ...
... is a species of air-breathing land snails or semi-slugs, terrestrial pulmonate gastropod mollusks in the ... Preece, R.C. (1996). "Diastole tenuistriata". IUCN Red List of Threatened Species. 1996: e.T6524A12787385. doi:10.2305/IUCN.UK. ... Diastole (gastropod), Fauna of the Pitcairn Islands, Molluscs of Oceania, Vulnerable fauna of Oceania, Gastropods described in ...
Ortiz, Wendy C. (May 11, 2023). "Diastole 1". BOMB. Official website Rhapsodomancy homepage Review of Excavation: A Memoir in ...
Diastole 05. Systole [1] Ghettoblaster Magazine, June 24, 2015. [2] MusicBox Pete June 29, 2015 "Hawking Introduces Us To Math ...
Mollusc Specialist Group (1996). "Diastole matafaoi". IUCN Red List of Threatened Species. 1996: e.T6523A12787323. doi:10.2305/ ...
The Mount Matafao different snail, scientific name Diastole matafaoi, was a species of air-breathing land snails or semi-slugs ... Mollusc Specialist Group (1996). "Diastole matafaoi". IUCN Red List of Threatened Species. 1996: e.T6523A12787323. doi:10.2305/ ... Diastole (gastropod), Extinct gastropods, Extinct animals of Oceania, Fauna of American Samoa, Molluscs of Oceania, Extinct ...
Energizing diastole. Heart Fail Clin. 2008 Jan;4(1):ix-xiii. Review. PMID 18313619. Baliga RR, Young JB. Never too late to ...
Siewert, A. K. (December 1922). "Über aktive Diastole" [About active diastole]. Zeitschrift für die Gesamte Experimentelle ... He also conducted studies on the biochemical changes in urine as a result of eating meat in 1912, and on diastole in 1922 ...
During diastole, the ventricle of heart must remain elastic or compliant enough and have capacity to hold incoming blood to ... Brutsaert, D. L.; Sys, S. U. (1989-10-01). "Relaxation and diastole of the heart". Physiological Reviews. 69 (4): 1228-1315. ...
In late ventricular diastole, the atrial chambers contract and send blood to the ventricles. This flow fills the ventricles ... Both valves are pressed open during the late stages of ventricular diastole; see Wiggers diagram at the P/QRS phase (at right ... Atrial systole lasts approximately 100 ms and ends prior to ventricular systole, as the atrial muscle returns to diastole. The ... Atrial systole occurs late in ventricular diastole and represents the contraction of myocardium of the left and right atria. ...
"diastole, n." Oxford University Press (Oxford), 1895. Nicolas, Nick. "Greek Unicode Issues: Punctuation Archived November 20, ... lower separation [mark]'), also known as a diastole, was an interpunct developed in late Ancient and Byzantine Greek texts ...
Ventricular systole Cardiac diastole ECG The EKG complex. P=P wave, PR=PR interval, QRS=QRS complex, QT=QT interval, ST=ST ...
These differ in the part of the heartbeat they make sound, during systole, or diastole. Yet, continuous murmurs create sound ... This causes collision with the mitral inflow during diastole. As such, the mitral valve orifice narrows. This results in ...
During diastole, the ventricles relax and fill with blood again. The left ventricle receives oxygenated blood from the left ...
During left ventricular diastole, after the pressure drops in the left ventricle due to relaxation of the ventricular ... In normal conditions, blood flows through an open mitral valve during diastole with contraction of the left atrium, and the ... Left atrial contraction (left atrial systole) (during left ventricular diastole) causes added blood to flow across the mitral ... Type IIIa pertains to restrictive motion during systole and diastole. Type IIIb pertains to restrictive motion during systole. ...
... diastole, and the pressures in the left atrium and the left ventricle during ventricular diastole will be equal. The result is ... As the heart rate increases, the amount of time that the ventricle is in diastole and can fill up with blood (called the ... Normally, the mitral valve is about 5 cm2 during diastole. Any decrease in area below 2 cm2 causes mitral stenosis. Early ... In normal cardiac physiology, the mitral valve opens during left ventricular diastole, to allow blood to flow from the left ...
Occurs during systole or continuously during both systole and diastole. (Murmurs occurring only during diastole are usually ...
Diastole Hospital Hill, Inc., University of Missouri-Kansas City, 1985. Farnsworth, Robert. Edgar Snow's Journey South of the ...
This limits ventricular filling during diastole, which increases end-diastolic volume. This can lead to a variety of cardiac ...
Atrial systole overlaps the end of the diastole, occurring in the sub-period known as ventricular diastole-late (see cycle ... Starting with the Diastole period: the low-volume plateau of "Isovolumic relaxation" stage, followed by a rapid rise and two ... This period is best viewed at the middle of the Wiggers diagram-see the panel labeled "Diastole". Here it shows pressure levels ... It consists of two periods: one during which the heart muscle relaxes and refills with blood, called diastole, following a ...
"Volume catheter parallel conductance varies between end-systole and end-diastole". IEEE Trans Biomed Eng. 54 (8): 1480-9. doi: ...
P I = v s y s t o l e − v d i a s t o l e v m e a n {\displaystyle PI={\frac {v_{systole}-v_{diastole}}{v_{mean}}}} Resistance ... What is left at the end of diastole (EDV) minus the stroke volume make up the end systolic volume (ESV). Circulatory system of ... Blood velocities in arteries are higher during systole than during diastole. One parameter to quantify this difference is the ...
As diastole ends, the ventricles begin depolarizing and, while ventricular pressure starts to rise owing to contraction, the ... The inverse operation is isovolumetric relaxation diastole with all valves optimally closed. In a healthy young adult, blood ...
During diastole, the ventricular pressure falls from the peak reached at the end of systole. When this pressure falls below the ... Diastole has four phases: isovolumetric relaxation, rapid filling, diastasis and atrial contraction. All of these phases can be ... In diastolic heart failure, the volume of blood contained in the ventricles during diastole is lower than it should be, and the ... Mathematics describing the relationship between the ratio of Systole to Diastole in accepted terms of End Systolic Volume to ...
As the heart rate becomes more robust, and the length of diastole decreases, the Na+/K+-ATPase, which removes the Na+ brought ... This occurs because of the decreased length of diastole with positive chronotropy. With an increased intracellular Ca++ ...
The stage in which water flows into the CV is called diastole. The contraction of the contractile vacuole and the expulsion of ...
In severe aortic regurgitation, additional blood reenters the left ventricle during diastole. This added volume of blood must ...
During cardiac diastole (when the heart chamber gets bigger) the aortic valve closes. Aortic stenosis most commonly is the ... connective tissue disorders such as Marfan syndrome or Ehlers-Danlos lead to imperfect closure of the valve during diastole, ...
A: Single-phase flow with minimal or absent diastole when the penis is flaccid. B: Increased systolic flow and reverse diastole ...
Atrial diastole is the relaxing of the atria, and ventricular diastole the relaxing of the ventricles. The term originates from ... Early diastole is a suction mechanism between the atrial and ventricular chambers. Then, in late ventricular diastole, the two ... Sabbah, H. N.; Stein, P. D. (1981). "Pressure-diameter relations during early diastole in dogs. The role of suction in Diastole ... Diastole (/daɪˈæstəli/ dy-AST-ə-lee) is the relaxed phase of the cardiac cycle when the chambers of the heart are re-filling ...
심장은 수축(수축기(systole))과 이완(이완기(diastole))의 빠른 조정인 심장 주기라고 불리는 순서대로 리듬감 있게 박동합니다. ...
Understanding the four stages of diastole during the cardiac cycle. This includes isovolumic relaxation, rapid filling, ... Lets talk diastole!. Diastole. First, lets discuss what is all involved in diastole. Diastole is the period of the cardiac ... Diastole starts when the aortic valve closes and ends at mitral valve closure. There are four stages to diastole:. *Isovolumic ... Understanding diastole is a key concept to have in order to evaluate diastolic function. By having an established knowledge on ...
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At the beginning of the ventricular diastole, pressure in ventricles is low due to previous isovolumetric relaxation, and ...
DIASTOLE. Diastole is the relaxation phase of the cardiac cycle. The Diastole consists of two events called Atrial Diastole and ... Relaxation stage or diastole.. SYSTOLE. Systole is the contraction phase of the cardiac cycle. The systole contains of two ... SYSTOLEDIASTOLESystole is the contraction phase of the cardiac cycle of the heart.Diastole is the relaxation phase of the ... it pumps blood from the heart Chambers into the aorta and a pulmonary artery.In Diastole stage, when the heart relaxes, it ...
Determinants of diastole. Table 2 shows an exhaustive list of the determinants of LV DF, divided between intrinsic and ... 1) a compliant chamber in diastole which allows LV filling with low FP; ... and is related to the trend of LV pressure and volume increase between mid and end-diastole. ...
... What Systolic, Diastolic Blood Pressure Numbers Mean. When you get your ...
Francine Birbragher. Humberto Castro. Published by Latin Art Core, edited by hCg Collection, Miami, 2020. Illustrated in color on full page 24 ...
Often contrasted with diastole. DERIVATIVES: sys·tol·ic / siˈstälik/ adj. ... Diastole , di·as·to·le / dīˈastl-ē/ • n. Physiol. the phase of the heartbeat when the heart muscle relaxes and allows the ...
Keywords: Ageing; Diastole; Nitric oxide; Nutrition. © 2016 The Authors. European Journal of Heart Failure © 2016 European ...
In this chapter, you will discover diseases that affect the cardiovascular system, the treatment of these diseases, and the effects on the clients general health status.
Use of the normal data and the Doppler techniques described in this study will allow confident assessment of diastolic function in children as well as in adults.
Diastole (66/1), Diego De Kerbiguet (80/1), Demoiselle Du Bois (80/1) ...
Meet A Member: Diastole Scholars Center A Green Business Network Member Spotlight We recently chatted with Diastole Scholars ...
Ventricular diastole. *. This phase begins with the opening of the atrioventricular (AV) valves. The mitral valve (located ... At the end of the diastole, left atrial contractions cause an increase in left atrial pressure, thus again creating a pressure ... The cardiac cycle is divided into 2 phases: ventricular diastole and ventricular systole. ...
Diastole (die-ASS-te-lee):. Period of relaxation and expansion of the heart when its chambers fill with blood.. Diffusion (dif- ... While the ventricles are contracting (systole), the atria are at rest (diastole) and are filling with blood once again. When ... The contraction phase, especially of the ventricles, is known as systole; the relaxation phase is known as diastole. The ... It is higher during systole (left ventricle contracting) and lower during diastole (left ventricle relaxing). ...
... left ventricular internal dimension at end diastole. LVIDs, left ventricular internal dimension at end systole. EF, ejection ...
Role of Diastole in Left Ventricular Function, II: Diagnosis and Treatment CE Article ... Shannan K. Hamlin, Penelope S. Villars, Joseph T. Kanusky, Andrew D. Shaw; Role of Diastole in Left Ventricular Function, II: ... Stage I is characterized by reduced left ventricular filling in early diastole with normal left ventricular and left atrial ...
diastole. phase in the cardiac cycle in which the ventricles relax between contractions (diastolic is the lower number of a ...
What are diastole and systole in blood pressure?. A persons blood pressure is measured by the balance between diastolic and ...
The abrupt diastole. That leaves you wondering. Why it was ever despite their assurances unlocked. Stars like lice along the ...
... left ventricular diameter in diastole; LVEF, left ventricular ejection fraction; ND, not determinate. ...
IIIa: Leaflet motion restricted in both systole and diastole *. Caused by rheumatic heart disease commonly ... increase in blood volume within the left atrium and hence an increased preload delivered to the left ventricle during diastole ...
Left ventriculogram in diastole. Panel C: End-systolic left ventriculogram demonstrating the classic apical ballooning and ...
The Systole and Diastole in Recycling By Stuart Kaplow on October 29, 2017. Posted in recycling, Sustainability ...
  • LV HDF were computed in three directions using the Navier-Stokes equations, reported in median N [interquartile range], and the ratio of transverse/longitudinal HDF was calculated for systole and diastole. (lu.se)
  • Atrial diastole is the relaxing of the atria, and ventricular diastole the relaxing of the ventricles. (wikipedia.org)
  • During early ventricular diastole, pressure in the two ventricles begins to drop from the peak reached during systole. (wikipedia.org)
  • Then, in late ventricular diastole, the two atrial chambers contract (atrial systole), causing blood pressure in both atria to increase and forcing additional blood flow into the ventricles. (wikipedia.org)
  • Heart during ventricular diastole. (ipfs.io)
  • Ventricular diastole is the period during which the ventricles are filling and relaxing, while atrial diastole is the period during which the atria are relaxing. (ipfs.io)
  • During ventricular diastole, the pressure in the (left and right) ventricles drops from the peak that it reaches in systole . (ipfs.io)
  • Occurs during last 0.1 second of ventricular diastole. (nonstopneuron.com)
  • What Is Ventricular Diastole? (thehealthboard.com)
  • The term "ventricular diastole" refers to one phase of a biologic activity known as the cardiac cycle, which is one complete heartbeat, during which the ventricles of the heart are relaxed. (thehealthboard.com)
  • During ventricular diastole, not only are the ventricles relaxing, they also are filling with blood in preparation for the next phase of the cardiac cycle. (thehealthboard.com)
  • This is why there are periods of relaxation such as ventricular diastole. (thehealthboard.com)
  • The ventricles, at the base of the heart, are relaxed during ventricular diastole. (thehealthboard.com)
  • Taking a person's blood pressure is closely related to the subject of ventricular diastole. (thehealthboard.com)
  • When the left ventricle is relaxed and refilling with blood, the period of the cardiac cycle known as ventricular diastole is the pressure that is left in the arteries. (thehealthboard.com)
  • A blood pressure measurement obtained by palpation cannot reveal the pressure remaining in the arteries during ventricular diastole, so it is less accurate information about what is going on inside of the body. (thehealthboard.com)
  • Ventricular diastole refers to one complete heartbeat cycle. (thehealthboard.com)
  • The Diastole consists of two events called Atrial Diastole and Ventricular Diastole. (topdifferences.com)
  • Stage I is characterized by reduced left ventricular filling in early diastole with normal left ventricular and left atrial pressures and normal compliance. (aacnjournals.org)
  • Typically, there is abrupt premature cessation of ventricular filling in early diastole, causing a dip-and-plateau or square-root pattern on ventricular pressure tracings. (medscape.com)
  • Diastole / d aɪ ˈ æ s t ə l iː / is the part of the cardiac cycle when the heart refills with blood following systole (contraction). (ipfs.io)
  • The last phase of diastole is atrial contraction. (cardioserv.net)
  • Diastole (/daɪˈæstəli/ dy-AST-ə-lee) is the relaxed phase of the cardiac cycle when the chambers of the heart are re-filling with blood. (wikipedia.org)
  • At the beginning of the cardiac cycle the atria, and the ventricles are synchronously approaching and retreating from relaxation and dilation, or diastole. (wikipedia.org)
  • Diastole is the period of the cardiac cycle that involves filling of the ventricles. (cardioserv.net)
  • There is much activity involved in one complete cardiac cycle, but it can be divided into two broad phases: diastole and systole. (thehealthboard.com)
  • Diastole is the relaxation phase of the cardiac cycle. (topdifferences.com)
  • Between heartbeats (cardiac diastole), these signals are silent. (newswise.com)
  • Diastole: relaxation. (nonstopneuron.com)
  • The main difference between LV relaxation and LV chamber compliance (the LV passive elastic properties) is that the former is a rapid, energy-dependent process, while the latter is passive and slower, and is related to the trend of LV pressure and volume increase between mid and end-diastole. (echobyweb.com)
  • Relaxation stage or diastole. (topdifferences.com)
  • The term diastole originates from the Greek word διαστολη , meaning dilation. (ipfs.io)
  • When, in late diastole, the ventricles become fully dilated (understood in imaging as LVEDV and RVEDV), the atria begin to contract, pumping blood to the ventricles. (wikipedia.org)
  • [3] In late diastole, i.e., the A-wave, as the left and right atria contract, the blood pressure in each atrium increases, forcing additional blood into the ventricles. (ipfs.io)
  • The open mitral valve allows blood in the atrium (accumulated during atrial diastole) to flow into the ventricle (see graphic at top). (wikipedia.org)
  • Ejection causes pressure within the ventricles to fall, and, simultaneously, the atria begin to refill (atrial diastole). (wikipedia.org)
  • Atrial diastole: 0.7 sec. (nonstopneuron.com)
  • Blood Pressure is the force of blood on the inside walls of blood vessels, measured by analyzing both the systolic blood pressure, the pressure when the heart pushes blood out into the arteries (systole), and the diastolic blood pressure, when the heart is at rest (diastole). (cdc.gov)
  • Early diastole is a suction mechanism between the atrial and ventricular chambers. (wikipedia.org)
  • Early diastole, i.e., the E-wave in the E/A ratio , is a suction mechanism. (ipfs.io)
  • and 0.5 sec in diastole (dilation), re-filling the four chambers of the heart, for a total of 0.8 sec to complete the cycle. (wikipedia.org)
  • However, it does not relax normally during the time between heartbeats when the blood returns from the body (diastole). (medlineplus.gov)
  • FUNCTIONIn systole stage, when the heart contracts, it pumps blood from the heart Chambers into the aorta and a pulmonary artery.In Diastole stage, when the heart relaxes, it allows the heart chambers to be filled with blood from venacava and pulmonary veins. (topdifferences.com)
  • Understanding diastole is a key concept to have in order to evaluate diastolic function. (cardioserv.net)
  • By having an established knowledge on what is occurring during each stage of diastole, we can have a better understanding of the physiologic standpoint for determining diastolic function. (cardioserv.net)
  • After stabilization coronary angiography was preceded and showed left main coronary artery had none significant plaque at distal part and a narrowing at mid part of left anterior descending artery which was mainly at systole with normal caliber in diastole and good distal flow (figures 1, 2). (ispub.com)
  • Although, this coronary Angiography had characteristic appearance for muscle Bridge, after normalization of blood pressure & pulse Rate, new projection revealed left anterior descending artery lesion became disappear in systole & diastole (fig3,4). (ispub.com)
  • You can see again the turbulence in the right ventricular outflow tract and on the side you can also see the laminar flow during diastole in the left main coronary artery. (medscape.com)
  • [1] Diastole is closely related to the phenomenon of recoil within ballistics . (ipfs.io)
  • Diastole starts when the aortic valve closes and ends at mitral valve closure. (cardioserv.net)
  • You can see some turbulence, which is not unexpected through the mitral-valve-ring annuloplasty during diastole. (medscape.com)
  • Wiggers diagram , showing various events during diastole (duration marked at bottom). (ipfs.io)
  • Panel B: Left ventriculogram in diastole. (cmaj.ca)
  • In electrocardiography had only Minor ST- T change& Angiography showed narrowing at mid part of left anterior descending artery which was mainly at systole with normal caliber in diastole and good distal flow but after normalization of blood pressure & pulse Rate, the left anterior descending artery lesion became disappear in systole & diastole. (ispub.com)
  • And then, there's this large cavity that is compressing the lateral wall of the left ventricle during diastole. (medscape.com)
  • Pressure-diameter relations during early diastole in dogs. (ipfs.io)
  • Therefore, ventricular filling is limited to early diastole. (medscape.com)
  • Pericardial fluid is considered normal in the absence of pericardial disease if it appears as a homogeneous or echo-free space between visceral pericardium and parietal pericardium seen only during systole when the heart contracts inward, with less that 1 mm separation of the pericardial layers during diastole. (medscape.com)
  • This ends this stage of diastole and starts the rapid filling phase. (cardioserv.net)
  • An image of the contractile vacuole in diastole (filling phase). (cellimagelibrary.org)
  • Looking an EKG, diastole begins after the T-wave and ends at the R-wave of QRS complex. (cardioserv.net)
  • Look up diastole in Wiktionary, the free dictionary. (ipfs.io)