A pathological constriction that can occur above (supravalvular stenosis), below (subvalvular stenosis), or at the AORTIC VALVE. It is characterized by restricted outflow from the LEFT VENTRICLE into the AORTA.
The valve between the left ventricle and the ascending aorta which prevents backflow into the left ventricle.
Surgical insertion of synthetic material to repair injured or diseased heart valves.
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).
The pathologic narrowing of the orifice of the PULMONARY VALVE. This lesion restricts blood outflow from the RIGHT VENTRICLE to the PULMONARY ARTERY. When the trileaflet valve is fused into an imperforate membrane, the blockage is complete.
A device that substitutes for a heart valve. It may be composed of biological material (BIOPROSTHESIS) and/or synthetic material.
Pathological conditions involving any of the various HEART VALVES and the associated structures (PAPILLARY MUSCLES and CHORDAE TENDINEAE).
Pathologic deposition of calcium salts in tissues.
The valve between the left atrium and left ventricle of the heart.
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.
The pathologic narrowing of the orifice of the TRICUSPID VALVE. This hinders the emptying of RIGHT ATRIUM leading to elevated right atrial pressure and systemic venous congestion. Tricuspid valve stenosis is almost always due to RHEUMATIC FEVER.
Procedures in which placement of CARDIAC CATHETERS is performed for therapeutic or diagnostic procedures.
Prosthesis, usually heart valve, composed of biological material and whose durability depends upon the stability of the material after pretreatment, rather than regeneration by host cell ingrowth. Durability is achieved 1, mechanically by the interposition of a cloth, usually polytetrafluoroethylene, between the host and the graft, and 2, chemically by stabilization of the tissue by intermolecular linking, usually with glutaraldehyde, after removal of antigenic components, or the use of reconstituted and restructured biopolymers.
Use or insertion of a tubular device into a duct, blood vessel, hollow organ, or body cavity for injecting or withdrawing fluids for diagnostic or therapeutic purposes. It differs from INTUBATION in that the tube here is used to restore or maintain patency in obstructions.
Ultrasonic recording of the size, motion, and composition of the heart and surrounding tissues. The standard approach is transthoracic.
A valve situated at the entrance to the pulmonary trunk from the right ventricle.
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.
Levels within a diagnostic group which are established by various measurement criteria applied to the seriousness of a patient's disorder.
Evaluation undertaken to assess the results or consequences of management and procedures used in combating disease in order to determine the efficacy, effectiveness, safety, and practicability of these interventions in individual cases or series.
The plan and delineation of prostheses in general or a specific prosthesis.
The treatment of patients without the use of allogeneic BLOOD TRANSFUSIONS or blood products.
Narrowing or stricture of any part of the CAROTID ARTERIES, most often due to atherosclerotic plaque formation. Ulcerations may form in atherosclerotic plaques and induce THROMBUS formation. Platelet or cholesterol emboli may arise from stenotic carotid lesions and induce a TRANSIENT ISCHEMIC ATTACK; CEREBROVASCULAR ACCIDENT; or temporary blindness (AMAUROSIS FUGAX). (From Adams et al., Principles of Neurology, 6th ed, pp 822-3)
A condition caused by underdevelopment of the whole left half of the heart. It is characterized by hypoplasia of the left cardiac chambers (HEART ATRIUM; HEART VENTRICLE), the AORTA, the AORTIC VALVE, and the MITRAL VALVE. Severe symptoms appear in early infancy when DUCTUS ARTERIOSUS closes.
Widening of a stenosed HEART VALVE by the insertion of a balloon CATHETER into the valve and inflation of the balloon.
Ultrasonic recording of the size, motion, and composition of the heart and surrounding tissues using a transducer placed in the esophagus.
Acquired degenerative dilation or expansion (ectasia) of normal BLOOD VESSELS, often associated with aging. They are isolated, tortuous, thin-walled vessels and sources of bleeding. They occur most often in mucosal capillaries of the GASTROINTESTINAL TRACT leading to GASTROINTESTINAL HEMORRHAGE and ANEMIA.
The movement and the forces involved in the movement of the blood through the CARDIOVASCULAR SYSTEM.
The valve consisting of three cusps situated between the right atrium and right ventricle of the heart.
Echocardiography applying the Doppler effect, with the superposition of flow information as colors on a gray scale in a real-time image.
Narrowing or constriction of a coronary artery.
A value equal to the total volume flow divided by the cross-sectional area of the vascular bed.
Studies in which individuals or populations are followed to assess the outcome of exposures, procedures, or effects of a characteristic, e.g., occurrence of disease.
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.
Occlusion of the outflow tract in either the LEFT VENTRICLE or the RIGHT VENTRICLE of the heart. This may result from CONGENITAL HEART DEFECTS, predisposing heart diseases, complications of surgery, or HEART NEOPLASMS.
Narrowing of the spinal canal.
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.
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.
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.
Tracheal stenosis is a medical condition characterized by an abnormal narrowing or constriction of the lumen of the trachea, which can lead to respiratory distress and other related symptoms.
Elements of limited time intervals, contributing to particular results or situations.
The main trunk of the systemic arteries.
Studies used to test etiologic hypotheses in which inferences about an exposure to putative causal factors are derived from data relating to characteristics of persons under study or to events or experiences in their past. The essential feature is that some of the persons under study have the disease or outcome of interest and their characteristics are compared with those of unaffected persons.
The downward displacement of the cuspal or pointed end of the trileaflet AORTIC VALVE causing misalignment of the cusps. Severe valve distortion can cause leakage and allow the backflow of blood from the ASCENDING AORTA back into the LEFT VENTRICLE, leading to aortic regurgitation.
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.
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.
An aspect of personal behavior or lifestyle, environmental exposure, or inborn or inherited characteristic, which, on the basis of epidemiologic evidence, is known to be associated with a health-related condition considered important to prevent.
Developmental abnormalities involving structures of the heart. These defects are present at birth but may be discovered later in life.
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).
Narrowing below the PULMONARY VALVE or well below it in the infundibuluar chamber where the pulmonary artery originates, usually caused by a defective VENTRICULAR SEPTUM or presence of fibrous tissues. It is characterized by restricted blood outflow from the RIGHT VENTRICLE into the PULMONARY ARTERY, exertional fatigue, DYSPNEA, and chest discomfort.
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 qualitative or quantitative estimation of the likelihood of adverse effects that may result from exposure to specified health hazards or from the absence of beneficial influences. (Last, Dictionary of Epidemiology, 1988)
Inflammation of the ENDOCARDIUM caused by BACTERIA that entered the bloodstream. The strains of bacteria vary with predisposing factors, such as CONGENITAL HEART DEFECTS; HEART VALVE DISEASES; HEART VALVE PROSTHESIS IMPLANTATION; or intravenous drug use.
Abnormal protrusion or billowing of one or both of the leaflets of MITRAL VALVE into the LEFT ATRIUM during SYSTOLE. This allows the backflow of blood into left atrium leading to MITRAL VALVE INSUFFICIENCY; SYSTOLIC MURMURS; or CARDIAC ARRHYTHMIA.
The condition of an anatomical structure's being constricted beyond normal dimensions.
Narrowing of the pyloric canal with varied etiology. A common form is due to muscle hypertrophy (PYLORIC STENOSIS, HYPERTROPHIC) seen in infants.
The worsening of a disease over time. This concept is most often used for chronic and incurable diseases where the stage of the disease is an important determinant of therapy and prognosis.
Cardiac manifestation of systemic rheumatological conditions, such as RHEUMATIC FEVER. Rheumatic heart disease can involve any part the heart, most often the HEART VALVES and the ENDOCARDIUM.
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.
A type of constriction that is caused by the presence of a fibrous ring (discrete type) below the AORTIC VALVE, anywhere between the aortic valve and the MITRAL VALVE. It is characterized by restricted outflow from the LEFT VENTRICLE into the AORTA.
Post-systolic relaxation of the HEART, especially the HEART VENTRICLES.
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.
An infant during the first month after birth.
A type of heart valve surgery that involves the repair, replacement, or reconstruction of the annuli of HEART VALVES. It includes shortening the circumference of the annulus to improve valve closing capacity and reinforcing the annulus as a step in more complex valve repairs.
Flaps within the VEINS that allow the blood to flow only in one direction. They are usually in the medium size veins that carry blood to the heart against gravity.
PRESSURE of the BLOOD on the ARTERIES and other BLOOD VESSELS.
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 birth defect characterized by the narrowing of the AORTA that can be of varying degree and at any point from the transverse arch to the iliac bifurcation. Aortic coarctation causes arterial HYPERTENSION before the point of narrowing and arterial HYPOTENSION beyond the narrowed portion.
Inflammation of the inner lining of the heart (ENDOCARDIUM), the continuous membrane lining the four chambers and HEART VALVES. It is often caused by microorganisms including bacteria, viruses, fungi, and rickettsiae. Left untreated, endocarditis can damage heart valves and become life-threatening.
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.
An abnormal balloon- or sac-like dilatation in the wall of AORTA.
A genetically heterogeneous, multifaceted disorder characterized by short stature, webbed neck, ptosis, skeletal malformations, hypertelorism, hormonal imbalance, CRYPTORCHIDISM, multiple cardiac abnormalities (most commonly including PULMONARY VALVE STENOSIS), and some degree of INTELLECTUAL DISABILITY. The phenotype bears similarities to that of TURNER SYNDROME that occurs only in females and has its basis in a 45, X karyotype abnormality. Noonan syndrome occurs in both males and females with a normal karyotype (46,XX and 46,XY). Mutations in a several genes (PTPN11, KRAS, SOS1, NF1 and RAF1) have been associated the the NS phenotype. Mutations in PTPN11 are the most common. LEOPARD SYNDROME, a disorder that has clinical features overlapping those of Noonan Syndrome, is also due to mutations in PTPN11. In addition, there is overlap with the syndrome called neurofibromatosis-Noonan syndrome due to mutations in NF1.
A pathological constriction occurring in the region below the AORTIC VALVE. It is characterized by restricted outflow from the LEFT VENTRICLE into the AORTA.
Developmental abnormalities in any portion of the VENTRICULAR SEPTUM resulting in abnormal communications between the two lower chambers of the heart. Classification of ventricular septal defects is based on location of the communication, such as perimembranous, inlet, outlet (infundibular), central muscular, marginal muscular, or apical muscular defect.
Backflow of blood from the RIGHT VENTRICLE into the RIGHT ATRIUM due to imperfect closure of the TRICUSPID VALVE.
A repeat operation for the same condition in the same patient due to disease progression or recurrence, or as followup to failed previous surgery.
Pathologic processes that affect patients after a surgical procedure. They may or may not be related to the disease for which the surgery was done, and they may or may not be direct results of the surgery.
Tomography using x-ray transmission and a computer algorithm to reconstruct the image.
Surgical incision into the chest wall.
A type of heart valve surgery that involves the repair, replacement, or reconstruction of the annulus of the MITRAL VALVE. It includes shortening the circumference of the annulus to improve valve closing capacity and reinforcing the annulus as a step in more complex valve repairs.

Investigation of distal aortic compliance and vasodilator responsiveness in heart failure due to proximal aortic stenosis in the guinea pig. (1/1864)

Hypotension and syncope are recognized features of chronic aortic stenosis. This study examined vasomotor responses and dynamic compliance in isolated abdominal aortae after chronic constriction of the ascending aorta. Guinea pigs underwent constriction of the ascending aorta or sham operation. Sections of descending aorta were removed for studies of contractile performance and compliance. Dynamic compliance was measured using a feedback-controlled pulsatile pressure system at frequencies of 0.5, 1.5 and 2.5 Hz and mean pressures from 40 to 100 mmHg. Chronic (149+/-6 days) aortic constriction resulted in significant increases in organ weight/body weight ratios for left ventricle (58%), right ventricle (100%) and lung (61%). The presence of heart failure was indicated by increased lung weights, left ventricular end-diastolic pressure and systemic vascular resistance, reduced cardiac output and increased levels of plasma atrial natriuretic peptide (166%), adrenaline (x20), noradrenaline (106%) and dopamine (x3). Aortic rings showed similar constrictor responses to phenylephrine and angiotensin II, but maximal vasodilator responses to acetylcholine and isoprenaline were significantly increased (144% and 48% respectively). Dilator responses to sodium nitroprusside, forskolin and cromokalim were unchanged. Compliance of all vessels decreased with increasing pulsatile frequency and to a lesser extent with increased mean pressure, but were similar in aortic-constricted and control groups. Chronic constriction of the ascending aorta resulted in heart failure and increased vasodilator responses to acetylcholine and isoprenaline in the distal aorta while dynamic compliance was unchanged. We hypothesize that increased endothelium-mediated vasodilatation may contribute to hypotension and syncope in patients with left ventricular outflow obstruction.  (+info)

Extent and severity of atherosclerotic involvement of the aortic valve and root in familial hypercholesterolaemia. (2/1864)

OBJECTIVE: To compare the frequency of valvar and supravalvar aortic stenosis in homozygous and heterozygous familial hypercholesterolaemia (FH). DESIGN: Analysis of life time cholesterol exposure and prevalence of aortic atherosclerosis in 84 consecutive cases attending a lipid clinic. SETTING: A tertiary referral centre in London. PATIENTS: Outpatients with FH (six homozygous, 78 heterozygous). INTERVENTIONS: Maintenance of lipid lowering treatment. MAIN OUTCOME MEASURES: Calculated cholesterol x years score (CYS) and echocardiographic measurement of aortic root diameter, aortic valve thickness, and transaortic gradient. RESULTS: Four homozygotes with a mean (SD) CYS of 387 (124) mmol/1 x years had severe aortic stenosis (treatment started after seven years of age), whereas the other two had echocardiographic evidence of supravalvar thickening but no aortic valve stenosis (treatment started before three years of age). On multivariate analysis, mean transaortic gradient correlated significantly with CYS (mean = 523 (175) mmol/1 x years) in heterozygotes (p = 0.0001), but only two had severe aortic valve and root involvement. CONCLUSIONS: In patients with familial hypercholesterolaemia, aortic stenosis is common in homozygotes, and aortic root involvement is always present despite the lower CYS than in heterozygotes. It appears to be determined by short term exposure to high cholesterol concentrations in early life. Conversely, aortic root and valve involvement are rare in heterozygotes and occur only with severe, prolonged hypercholesterolaemia, possibly accelerating age related degenerative effects.  (+info)

Development of atherosclerotic lesions in cholesterol-loaded rabbits. (3/1864)

To examine both of the target vessels and the optimal time of their endothelial denudation to study vascular restenosis after balloon injury in cholesterol-loaded rabbits, we made 36 atherosclerotic rabbits by feeding a hypercholesterol diet, and histologically examined the onset time and the development of atherosclerosis. Atheromatous changes were observed first after the 5th week in the thoracic aorta from the start of the diet, and then extended to the abdominal aorta, coronary artery with time. The atherosclerotic lesions in the thoracic aorta and the proximal portion of the coronary artery showed high-grade concentric intimal thickening with luminal stenosis. The abdominal aortic lesion mildly progressed. In the renal, carotid and femoral arteries, in contrast, slight atheroscleromatous changes developed during the diet period. These results suggest that the thoracic and abdominal aortas and the coronary artery would be suitable as target vessels to study vascular restenosis after balloon injury, and the endothelial denudation of these vessels should be performed between the 8th and 15th week in this diet protocol for an accurate analysis.  (+info)

Bileaflet mechanical prostheses for aortic valve replacement in patients younger than 65 years and 65 years of age or older: major thromboembolic and hemorrhagic complications. (4/1864)

OBJECTIVE: To determine major thromboembolic and hemorrhagic complications and predictive risk factors associated with aortic valve replacement (AVR), using bileaflet mechanical prostheses (CarboMedics and St. Jude Medical). DESIGN: A case series. SETTING: Cardiac surgical services at the teaching institutions of the University of British Columbia. PATIENTS AND METHODS: Patients 2 age groups who had undergone AVR between 1989 and 1994 were studied. Group 1 comprised 384 patients younger than 65 years. Group 2 comprised 215 patients 65 years of age and older. RESULTS: The linearized rates of major thromboembolism (TE) occurring after AVR were 1.54%/patient-year for group 1 and 3.32%/patient-year for group 2; the rates for major TE occurring more than 30 days after AVR were 1.13%/patient-year for group 1 and 1.55%/patient-year for group 2. The crude rates for major TE occurring within 30 days of AVR were 1.04% for group 1 and 3.72% for group 2. The death rate from major TE in group 1 was 0.31%/patient-year and in group 2 was 0.88%/patient-year. Of the major TE events occurring within 30 days, 100% of patients in both age groups were inadequately anticoagulated at the time of the event, and for events occurring more than 30 days after AVR, 45% in group 1 and 57% in group 2 were inadequately anticoagulated (INR less than 2.0). The overall linearized rates of major hemorrhage were 1.54%/patient-year for group 1 and 2.21%/patient-year for group 2. There were no cases of prosthesis thrombosis in either group. The mean (and standard error) overall freedom from major TE for group 1 patients at 5 years was 95.6% (1.4%) and with exclusion of early events was 96.7% (1.3%); for group 2 patients the rates were 90.0% (3.2%) and 93.7% (3.0%), respectively. The mean (and SE) overall freedom from major and fatal TE and hemorrhage for group 1 patients was 90.1% (2.3%) and with exclusion of early events was 91.2% (2.3%); for group 2 patients the rates were 87.9% (3.1%) and 92.5% (2.9%), respectively. The 5-year rate for freedom from valve-related death for group 1 patients was 96.3% (2.1%) and for group 2 patients was 97.2% (1.2%). CONCLUSION: The thromboembolic and hemorrhagic complications after AVR with bileaflet mechanical prostheses occur more frequently and result in more deaths in patients 65 years of age and older than in patients years younger than 65 years.  (+info)

Minimally invasive aortic valve replacement through a transverse sternotomy: a word of caution. (5/1864)

OBJECTIVES: To compare aortic valve replacement (AVR) using a minimally invasive approach through a transverse sternotomy with the established approach of median sternotomy. DESIGN: Retrospective, case-control study. PATIENTS: Fourteen high risk patients (median age 78, Parsonnet score of 18%) who underwent AVR performed through a minimally invasive transverse sternotomy were compared with a historical group of patients matched for age, sex, and Parsonnet score who underwent AVR performed through a median sternotomy by the same surgeon. OUTCOME MEASURES: Cross clamp time, total bypass time, intensive care stay, postoperative in-hospital stay, morbidity, and mortality. RESULTS: There were two deaths in the minimally invasive group and none in the control group (NS). The cross clamp and total bypass times were longer in the minimally invasive group (67 and 92 minutes v 46 and 66 minutes, p < 0.001). There was a higher incidence of re-exploration for bleeding (14% v 0%) and paravalvar leaks (21% v 0%) in the minimally invasive group but these differences were not significant. The minimally invasive group had a longer postoperative in-hospital stay (p = 0.025). The incidence of mortality or major morbidity was 43% (six of 14) in the minimally invasive group and 7% (one of 14) in the matched pairs (p = 0.013). CONCLUSIONS: AVR can be performed through a transverse sternotomy but the operation takes longer and there is an unacceptably high incidence of morbidity and mortality.  (+info)

Double outlet right ventricle. Study of 27 cases. (6/1864)

Out of 1610 children's hearts with congenital malformations there were 27 specimens showing double outlet right ventricle. Cases with dextrocardia, situs inversus, or l-venticular loop were excluded. Anatomical examination was performed with particular reference to the infundibular region, the great vessels, and the ventricular septum. The commonest associated malformations were ventricular septal defect and pulmonary stenosis. Aortic stenosis was the predominant finding in those cases dying in the neonatal period. An aortic conus was associated with pulmonary stenosis, ventricular septal defect, and d-transposition, a pulmonary conus with ventricular septal defect and a double conus with stenosis of either great vessel. The anterior vessel always had a muscular conus and the posterior vessel was commonly stenotic.  (+info)

Combined aortic and mitral stenosis in mucopolysaccharidosis type I-S (Ullrich-Scheie syndrome). (7/1864)

The genetic mucopolysaccharidosis syndromes (MPS) are autosomal recessive inborn errors of metabolism. Heart valve involvement in MPS is not uncommon but only a few case reports of successful cardiac surgery are available. In particular, reports of combined aortic and mitral stenosis associated with MPS type I-S are very rare. Both type I and type VI MPS are associated with significant left sided valvar heart disease that requires surgical valve replacement because of irregular valve thickening, fibrosis, and calcification. A 35 year old man had severe mitral valve stenosis after successful surgical replacement of a stenotic aortic valve. Valvar heart disease was investigated by cardiac ultrasound and left heart catheterisation. Histomorphological characterisation of the affected mitral valve was performed. The case illustrates typically associated clinical features of cardiac and extracardiac abnormalities found in MPS type I-S.  (+info)

Effect of NO donors on LV diastolic function in patients with severe pressure-overload hypertrophy. (8/1864)

BACKGROUND: Previous experimental studies have shown that nitric oxide (NO) modulates cardiac function by an abbreviation of systolic contraction and an enhancement of diastolic relaxation. However, the response to NO donors of patients with severe pressure-overload hypertrophy and diastolic dysfunction is unknown. METHODS AND RESULTS: Intracoronary NO donors were given to 17 patients with severe aortic stenosis. A dose-response curve was obtained with nitroglycerin (30, 90, and 150 microg) in 11 patients and sodium nitroprusside (1, 2, and 4 microg/min) in 6. Left ventricular (LV) high-fidelity pressure measurements with simultaneous LV angiograms were performed at baseline and after the maximal dose of NO. The dose-response curve for intracoronary NO donors showed a marked fall in LV end-diastolic pressure, from 23 to 14 mm Hg (-39%; P<0.0001), whereas LV peak systolic pressure fell only slightly, from 206 to 196 mm Hg (-4%; P<0.01). End-diastolic chamber stiffness decreased from 0.12 to 0.07 mm Hg/mL (P<0.0001) and end-systolic stiffness from 1.6 to 1.3 mm Hg/mL (P<0.01). Heart rate, right atrial pressure, LV ejection fraction, the time constant of isovolumic pressure decay (tau), and LV filling rates remained unchanged. CONCLUSIONS: In patients with severe pressure-overload hypertrophy, intracoronary NO donors exert a marked decrease in LV end-diastolic pressure without affecting LV systolic pump function. Thus, the hypertrophied myocardium appears to be particularly susceptible to NO donors, with a marked improvement in diastolic function.  (+info)

Aortic valve stenosis is a cardiac condition characterized by the narrowing or stiffening of the aortic valve, which separates the left ventricle (the heart's main pumping chamber) from the aorta (the large artery that carries oxygen-rich blood to the rest of the body). This narrowing or stiffening prevents the aortic valve from opening fully, resulting in reduced blood flow from the left ventricle to the aorta and the rest of the body.

The narrowing can be caused by several factors, including congenital heart defects, calcification (hardening) of the aortic valve due to aging, or scarring of the valve due to rheumatic fever or other inflammatory conditions. As a result, the left ventricle must work harder to pump blood through the narrowed valve, which can lead to thickening and enlargement of the left ventricular muscle (left ventricular hypertrophy).

Symptoms of aortic valve stenosis may include chest pain or tightness, shortness of breath, fatigue, dizziness or fainting, and heart palpitations. Severe aortic valve stenosis can lead to serious complications such as heart failure, arrhythmias, or even sudden cardiac death. Treatment options may include medications to manage symptoms, lifestyle changes, or surgical intervention such as aortic valve replacement.

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.

Heart valve prosthesis implantation is a surgical procedure where an artificial heart valve is inserted to replace a damaged or malfunctioning native heart valve. This can be necessary for patients with valvular heart disease, including stenosis (narrowing) or regurgitation (leaking), who do not respond to medical management and are at risk of heart failure or other complications.

There are two main types of artificial heart valves used in prosthesis implantation: mechanical valves and biological valves. Mechanical valves are made of synthetic materials, such as carbon and metal, and can last a long time but require lifelong anticoagulation therapy to prevent blood clots from forming. Biological valves, on the other hand, are made from animal or human tissue and typically do not require anticoagulation therapy but may have a limited lifespan and may need to be replaced in the future.

The decision to undergo heart valve prosthesis implantation is based on several factors, including the patient's age, overall health, type and severity of valvular disease, and personal preferences. The procedure can be performed through traditional open-heart surgery or minimally invasive techniques, such as robotic-assisted surgery or transcatheter aortic valve replacement (TAVR). Recovery time varies depending on the approach used and individual patient factors.

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.

Pulmonary Valve Stenosis is a cardiac condition where the pulmonary valve, located between the right ventricle and the pulmonary artery, has a narrowed opening. This stenosis (narrowing) can cause obstruction of blood flow from the right ventricle to the lungs. The narrowing can be caused by a fusion of the valve leaflets, thickened or calcified valve leaflets, or rarely, a dysplastic valve.

The severity of Pulmonary Valve Stenosis is classified based on the gradient pressure across the valve, which is measured during an echocardiogram. A mild stenosis has a gradient of less than 30 mmHg, moderate stenosis has a gradient between 30-59 mmHg, and severe stenosis has a gradient of 60 mmHg or higher.

Mild Pulmonary Valve Stenosis may not require treatment, while more severe cases may need to be treated with balloon valvuloplasty or surgical valve replacement. If left untreated, Pulmonary Valve Stenosis can lead to right ventricular hypertrophy, heart failure, and other complications.

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.

Heart valve diseases are a group of conditions that affect the function of one or more of the heart's four valves (tricuspid, pulmonic, mitral, and aortic). These valves are responsible for controlling the direction and flow of blood through the heart. Heart valve diseases can cause the valves to become narrowed (stenosis), leaky (regurgitation or insufficiency), or improperly closed (prolapse), leading to disrupted blood flow within the heart and potentially causing symptoms such as shortness of breath, fatigue, chest pain, and irregular heart rhythms. The causes of heart valve diseases can include congenital defects, age-related degenerative changes, infections, rheumatic heart disease, and high blood pressure. Treatment options may include medications, surgical repair or replacement of the affected valve(s), or transcatheter procedures.

Calcinosis is a medical condition characterized by the abnormal deposit of calcium salts in various tissues of the body, commonly under the skin or in the muscles and tendons. These calcium deposits can form hard lumps or nodules that can cause pain, inflammation, and restricted mobility. Calcinosis can occur as a complication of other medical conditions, such as autoimmune disorders, kidney disease, and hypercalcemia (high levels of calcium in the blood). In some cases, the cause of calcinosis may be unknown. Treatment for calcinosis depends on the underlying cause and may include medications to manage calcium levels, physical therapy, and surgical removal of large deposits.

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.

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.

Tricuspid valve stenosis is a cardiac condition characterized by the narrowing or stiffening of the tricuspid valve, which is located between the right atrium and right ventricle in the heart. This narrowing or stiffening restricts the normal flow of blood from the right atrium into the right ventricle, causing increased pressure in the right atrium and reduced blood flow to the lungs.

The tricuspid valve typically has three leaflets or cusps that open and close to regulate the flow of blood between the right atrium and right ventricle. In tricuspid valve stenosis, these leaflets become thickened, calcified, or fused together, leading to a reduced opening size and impaired function.

The most common causes of tricuspid valve stenosis include rheumatic heart disease, congenital heart defects, carcinoid syndrome, and infective endocarditis. Symptoms may include fatigue, shortness of breath, swelling in the legs and abdomen, and irregular heartbeats. Treatment options depend on the severity of the condition and underlying causes but may involve medications, surgical repair or replacement of the valve, or catheter-based procedures.

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.

A bioprosthesis is a type of medical implant that is made from biological materials, such as heart valves or tendons taken from animals (xenografts) or humans (allografts). These materials are processed and sterilized to be used in surgical procedures to replace damaged or diseased tissues in the body.

Bioprosthetic implants are often used in cardiac surgery, such as heart valve replacement, because they are less likely to cause an immune response than synthetic materials. However, they may have a limited lifespan due to calcification and degeneration of the biological tissue over time. Therefore, bioprosthetic implants may need to be replaced after several years.

Bioprostheses can also be used in other types of surgical procedures, such as ligament or tendon repair, where natural tissue is needed to restore function and mobility. These prostheses are designed to mimic the properties of native tissues and provide a more physiological solution than synthetic materials.

Catheterization is a medical procedure in which a catheter (a flexible tube) is inserted into the body to treat various medical conditions or for diagnostic purposes. The specific definition can vary depending on the area of medicine and the particular procedure being discussed. Here are some common types of catheterization:

1. Urinary catheterization: This involves inserting a catheter through the urethra into the bladder to drain urine. It is often performed to manage urinary retention, monitor urine output in critically ill patients, or assist with surgical procedures.
2. Cardiac catheterization: A procedure where a catheter is inserted into a blood vessel, usually in the groin or arm, and guided to the heart. This allows for various diagnostic tests and treatments, such as measuring pressures within the heart chambers, assessing blood flow, or performing angioplasty and stenting of narrowed coronary arteries.
3. Central venous catheterization: A catheter is inserted into a large vein, typically in the neck, chest, or groin, to administer medications, fluids, or nutrition, or to monitor central venous pressure.
4. Peritoneal dialysis catheterization: A catheter is placed into the abdominal cavity for individuals undergoing peritoneal dialysis, a type of kidney replacement therapy.
5. Neurological catheterization: In some cases, a catheter may be inserted into the cerebrospinal fluid space (lumbar puncture) or the brain's ventricular system (ventriculostomy) to diagnose or treat various neurological conditions.

These are just a few examples of catheterization procedures in medicine. The specific definition and purpose will depend on the medical context and the particular organ or body system involved.

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.

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.

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.

A Severity of Illness Index is a measurement tool used in healthcare to assess the severity of a patient's condition and the risk of mortality or other adverse outcomes. These indices typically take into account various physiological and clinical variables, such as vital signs, laboratory values, and co-morbidities, to generate a score that reflects the patient's overall illness severity.

Examples of Severity of Illness Indices include the Acute Physiology and Chronic Health Evaluation (APACHE) system, the Simplified Acute Physiology Score (SAPS), and the Mortality Probability Model (MPM). These indices are often used in critical care settings to guide clinical decision-making, inform prognosis, and compare outcomes across different patient populations.

It is important to note that while these indices can provide valuable information about a patient's condition, they should not be used as the sole basis for clinical decision-making. Rather, they should be considered in conjunction with other factors, such as the patient's overall clinical presentation, treatment preferences, and goals of care.

Treatment outcome is a term used to describe the result or effect of medical treatment on a patient's health status. It can be measured in various ways, such as through symptoms improvement, disease remission, reduced disability, improved quality of life, or survival rates. The treatment outcome helps healthcare providers evaluate the effectiveness of a particular treatment plan and make informed decisions about future care. It is also used in clinical research to compare the efficacy of different treatments and improve patient care.

Prosthesis design is a specialized field in medical device technology that involves creating and developing artificial substitutes to replace a missing body part, such as a limb, tooth, eye, or internal organ. The design process typically includes several stages: assessment of the patient's needs, selection of appropriate materials, creation of a prototype, testing and refinement, and final fabrication and fitting of the prosthesis.

The goal of prosthesis design is to create a device that functions as closely as possible to the natural body part it replaces, while also being comfortable, durable, and aesthetically pleasing for the patient. The design process may involve collaboration between medical professionals, engineers, and designers, and may take into account factors such as the patient's age, lifestyle, occupation, and overall health.

Prosthesis design can be highly complex, particularly for advanced devices such as robotic limbs or implantable organs. These devices often require sophisticated sensors, actuators, and control systems to mimic the natural functions of the body part they replace. As a result, prosthesis design is an active area of research and development in the medical field, with ongoing efforts to improve the functionality, comfort, and affordability of these devices for patients.

Bloodless medical and surgical procedures refer to the techniques and practices used to prevent or minimize blood loss during surgery and other medical treatments, while also avoiding the use of blood transfusions. This approach is often used for patients who refuse blood transfusions due to religious beliefs, or for those with conditions that make it difficult or risky to receive blood transfusions, such as rare blood types or certain genetic disorders.

Bloodless medical and surgical procedures may involve a variety of techniques, including:

1. Preoperative preparation: This includes optimizing the patient's hemoglobin levels through iron supplementation, erythropoietin therapy, or nutritional interventions. It may also involve managing the patient's anticoagulation medications and other medical conditions that could increase the risk of bleeding.
2. Intraoperative management: This includes meticulous surgical technique to minimize blood loss, use of specialized surgical instruments and techniques (such as electrosurgery or argon beam coagulation), hypotensive anesthesia, and cell salvage devices that collect and reinfuse the patient's own blood.
3. Postoperative care: This includes close monitoring of the patient's hematocrit levels, use of medications to stimulate red blood cell production, and management of any postoperative bleeding or anemia.

Bloodless medical and surgical procedures have been shown to be safe and effective in a variety of clinical settings, and can help reduce the need for blood transfusions and their associated risks, such as infection, allergic reactions, and immune suppression.

Carotid stenosis is a medical condition that refers to the narrowing or constriction of the lumen (inner space) of the carotid artery. The carotid arteries are major blood vessels that supply oxygenated blood to the head and neck. Carotid stenosis usually results from the buildup of plaque, made up of fat, cholesterol, calcium, and other substances, on the inner walls of the artery. This process is called atherosclerosis.

As the plaque accumulates, it causes the artery to narrow, reducing blood flow to the brain. Severe carotid stenosis can increase the risk of stroke, as a clot or debris from the plaque can break off and travel to the brain, blocking a smaller blood vessel and causing tissue damage or death.

Carotid stenosis is typically diagnosed through imaging tests such as ultrasound, CT angiography, or MRI angiography. Treatment options may include lifestyle modifications (such as quitting smoking, controlling blood pressure, and managing cholesterol levels), medications to reduce the risk of clots, or surgical procedures like endarterectomy or stenting to remove or bypass the blockage.

Hypoplastic Left Heart Syndrome (HLHS) is a congenital heart defect in which the left side of the heart is underdeveloped. This includes the mitral valve, left ventricle, aortic valve, and aorta. The left ventricle is too small or absent, and the aorta is narrowed or poorly formed. As a result, blood cannot be adequately pumped to the body. Oxygen-rich blood from the lungs mixes with oxygen-poor blood in the heart, and the body does not receive enough oxygen-rich blood. HLHS is a serious condition that requires immediate medical attention and often surgical intervention.

Balloon valvuloplasty is a medical procedure used to treat heart valve stenosis or narrowing. It involves the use of a thin, flexible tube (catheter) with a balloon at its tip, which is guided through a blood vessel to the narrowed heart valve. Once in position, the balloon is inflated to stretch and widen the valve opening, improving blood flow. After the valve is widened, the balloon is deflated and the catheter is removed. This procedure can be performed on various heart valves, including the aortic, mitral, and pulmonary valves.

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.

Angiodysplasia is a vascular disorder characterized by the dilation and abnormal formation of blood vessels, particularly in the gastrointestinal (GI) tract. These abnormal blood vessels are prone to leakage or rupture, which can lead to bleeding. Angiodysplasia is most commonly found in the colon but can occur in other parts of the GI tract as well. It is more common in older adults and can cause symptoms such as anemia, fatigue, and bloody stools. The exact cause of angiodysplasia is not known, but it may be associated with chronic low-grade inflammation or increased pressure in the blood vessels. Treatment options include endoscopic therapies to stop bleeding, medications to reduce acid production in the stomach, and surgery in severe cases.

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.

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.

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.

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.

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.

Follow-up studies are a type of longitudinal research that involve repeated observations or measurements of the same variables over a period of time, in order to understand their long-term effects or outcomes. In medical context, follow-up studies are often used to evaluate the safety and efficacy of medical treatments, interventions, or procedures.

In a typical follow-up study, a group of individuals (called a cohort) who have received a particular treatment or intervention are identified and then followed over time through periodic assessments or data collection. The data collected may include information on clinical outcomes, adverse events, changes in symptoms or functional status, and other relevant measures.

The results of follow-up studies can provide important insights into the long-term benefits and risks of medical interventions, as well as help to identify factors that may influence treatment effectiveness or patient outcomes. However, it is important to note that follow-up studies can be subject to various biases and limitations, such as loss to follow-up, recall bias, and changes in clinical practice over time, which must be carefully considered when interpreting the results.

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.

Ventricular outflow obstruction is a term used in cardiology to describe a condition where there is an obstruction or narrowing in the flow of blood as it exits the heart's ventricles (the lower chambers of the heart). This obstruction can occur due to various reasons such as congenital heart defects, hypertrophic cardiomyopathy, or calcification of the aortic valve.

In a normal heart, the left ventricle pumps oxygenated blood into the aorta through the aortic valve, and the right ventricle pumps deoxygenated blood into the pulmonary artery through the pulmonic valve. Any obstruction in these outflow tracts can lead to increased pressure within the ventricles, which can result in various symptoms such as shortness of breath, chest pain, dizziness, or fatigue.

The severity of the obstruction and the resulting symptoms can vary depending on the location and extent of the narrowing. Treatment options may include medications, surgical procedures, or catheter-based interventions to alleviate the obstruction and improve blood flow.

Spinal stenosis is a narrowing of the spinal canal or the neural foramina (the openings through which nerves exit the spinal column), typically in the lower back (lumbar) or neck (cervical) regions. This can put pressure on the spinal cord and/or nerve roots, causing pain, numbness, tingling, or weakness in the affected areas, often in the legs, arms, or hands. It's most commonly caused by age-related wear and tear, but can also be due to degenerative changes, herniated discs, tumors, or spinal injuries.

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.

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.

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.

Tracheal stenosis is a medical condition characterized by the abnormal narrowing of the trachea (windpipe), which can lead to difficulty breathing. This narrowing can be caused by various factors such as inflammation, scarring, or the growth of abnormal tissue in the airway. Symptoms may include wheezing, coughing, shortness of breath, and chest discomfort, particularly during physical activity. Treatment options for tracheal stenosis depend on the severity and underlying cause of the condition and may include medications, bronchodilators, corticosteroids, or surgical interventions such as laser surgery, stent placement, or tracheal reconstruction.

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.

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.

Retrospective studies, also known as retrospective research or looking back studies, are a type of observational study that examines data from the past to draw conclusions about possible causal relationships between risk factors and outcomes. In these studies, researchers analyze existing records, medical charts, or previously collected data to test a hypothesis or answer a specific research question.

Retrospective studies can be useful for generating hypotheses and identifying trends, but they have limitations compared to prospective studies, which follow participants forward in time from exposure to outcome. Retrospective studies are subject to biases such as recall bias, selection bias, and information bias, which can affect the validity of the results. Therefore, retrospective studies should be interpreted with caution and used primarily to generate hypotheses for further testing in prospective studies.

Aortic valve prolapse is a cardiac condition in which the aortic valve leaflets bulge or billow into the left ventricle during systole, the phase of the heart cycle when the ventricles contract to pump blood out of the heart. The aortic valve typically has three leaflets that open and close to regulate the flow of blood between the left ventricle and the aorta. In aortic valve prolapse, one or more of these leaflets become floppy, allowing blood to leak back into the left ventricle, a condition known as aortic regurgitation.

Aortic valve prolapse can be congenital or acquired. Some people are born with abnormalities in the aortic valve that make it more prone to prolapse, while others may develop the condition due to degenerative changes in the valve tissue over time. Certain factors, such as Marfan syndrome, bicuspid aortic valve, and infective endocarditis, can increase the risk of aortic valve prolapse.

The symptoms of aortic valve prolapse can vary depending on the severity of the condition. Mild cases may not cause any noticeable symptoms, while more severe cases can lead to shortness of breath, fatigue, chest pain, and irregular heart rhythms. Treatment for aortic valve prolapse may include monitoring, medication, or surgical repair or replacement of the aortic valve.

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.

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.

Medical Definition:

"Risk factors" are any attribute, characteristic or exposure of an individual that increases the likelihood of developing a disease or injury. They can be divided into modifiable and non-modifiable risk factors. Modifiable risk factors are those that can be changed through lifestyle choices or medical treatment, while non-modifiable risk factors are inherent traits such as age, gender, or genetic predisposition. Examples of modifiable risk factors include smoking, alcohol consumption, physical inactivity, and unhealthy diet, while non-modifiable risk factors include age, sex, and family history. It is important to note that having a risk factor does not guarantee that a person will develop the disease, but rather indicates an increased susceptibility.

Congenital heart defects (CHDs) are structural abnormalities in the heart that are present at birth. They can affect any part of the heart's structure, including the walls of the heart, the valves inside the heart, and the major blood vessels that lead to and from the heart.

Congenital heart defects can range from mild to severe and can cause various symptoms depending on the type and severity of the defect. Some common symptoms of CHDs include cyanosis (a bluish tint to the skin, lips, and fingernails), shortness of breath, fatigue, poor feeding, and slow growth in infants and children.

There are many different types of congenital heart defects, including:

1. Septal defects: These are holes in the walls that separate the four chambers of the heart. The two most common septal defects are atrial septal defect (ASD) and ventricular septal defect (VSD).
2. Valve abnormalities: These include narrowed or leaky valves, which can affect blood flow through the heart.
3. Obstruction defects: These occur when blood flow is blocked or restricted due to narrowing or absence of a part of the heart's structure. Examples include pulmonary stenosis and coarctation of the aorta.
4. Cyanotic heart defects: These cause a lack of oxygen in the blood, leading to cyanosis. Examples include tetralogy of Fallot and transposition of the great arteries.

The causes of congenital heart defects are not fully understood, but genetic factors and environmental influences during pregnancy may play a role. Some CHDs can be detected before birth through prenatal testing, while others may not be diagnosed until after birth or later in childhood. Treatment for CHDs may include medication, surgery, or other interventions to improve blood flow and oxygenation of the body's tissues.

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.

Pulmonary subvalvular stenosis is a rare cardiac condition that refers to the narrowing or obstruction of the pulmonary valve or the outflow tract below it, within the right ventricle of the heart. This results in restricted blood flow from the right ventricle to the pulmonary artery and subsequently to the lungs.

The narrowing can be caused by various factors such as a membranous shelf-like structure (dysplasia), a fibrous ring, or a tunnel-like narrowing of the outflow tract (tunneling). The severity of the stenosis may vary from mild to severe, and symptoms can range from shortness of breath, fatigue, and chest pain to more serious complications like heart failure or arrhythmias.

Diagnosis typically involves imaging tests such as echocardiography, cardiac MRI, or cardiac catheterization. Treatment options depend on the severity of the stenosis and may include monitoring, medications, or invasive procedures such as balloon dilation or surgical repair.

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.

Risk assessment in the medical context refers to the process of identifying, evaluating, and prioritizing risks to patients, healthcare workers, or the community related to healthcare delivery. It involves determining the likelihood and potential impact of adverse events or hazards, such as infectious diseases, medication errors, or medical devices failures, and implementing measures to mitigate or manage those risks. The goal of risk assessment is to promote safe and high-quality care by identifying areas for improvement and taking action to minimize harm.

Bacterial endocarditis is a medical condition characterized by the inflammation and infection of the inner layer of the heart, known as the endocardium. This infection typically occurs when bacteria enter the bloodstream and attach themselves to damaged or abnormal heart valves or other parts of the endocardium. The bacteria can then multiply and cause the formation of vegetations, which are clusters of infected tissue that can further damage the heart valves and lead to serious complications such as heart failure, stroke, or even death if left untreated.

Bacterial endocarditis is a relatively uncommon but potentially life-threatening condition that requires prompt medical attention. Risk factors for developing bacterial endocarditis include pre-existing heart conditions such as congenital heart defects, artificial heart valves, previous history of endocarditis, or other conditions that damage the heart valves. Intravenous drug use is also a significant risk factor for this condition.

Symptoms of bacterial endocarditis may include fever, chills, fatigue, muscle and joint pain, shortness of breath, chest pain, and a new or changing heart murmur. Diagnosis typically involves a combination of medical history, physical examination, blood cultures, and imaging tests such as echocardiography. Treatment usually involves several weeks of intravenous antibiotics to eradicate the infection, and in some cases, surgical intervention may be necessary to repair or replace damaged heart valves.

Mitral valve prolapse (MVP) is a heart condition where the mitral valve, which separates the left atrium and left ventricle in the heart, doesn't function properly. In MVP, one or both of the mitral valve flaps (known as leaflets) bulge or billow into the left atrium during the contraction of the left ventricle. This prolapse can cause a leakage of blood back into the atrium, known as mitral regurgitation. In many cases, MVP is asymptomatic and doesn't require treatment, but in some instances, it may lead to complications such as infective endocarditis or arrhythmias. The exact causes of MVP are not fully understood, but it can be associated with certain genetic factors, connective tissue disorders, and mitral valve abnormalities present at birth.

Pathological constriction refers to an abnormal narrowing or tightening of a body passage or organ, which can interfere with the normal flow of blood, air, or other substances through the area. This constriction can occur due to various reasons such as inflammation, scarring, or abnormal growths, and can affect different parts of the body, including blood vessels, airways, intestines, and ureters. Pathological constriction can lead to a range of symptoms and complications depending on its location and severity, and may require medical intervention to correct.

Pyloric stenosis is a condition that results in the narrowing or complete obstruction of the pylorus, which is the opening from the stomach into the small intestine. This narrowing is usually caused by hypertrophy (thickening) of the muscles in the pylorus, making it difficult for food to pass from the stomach into the duodenum.

The most common form of this condition is infantile hypertrophic pyloric stenosis, which typically affects infants between 3-6 weeks of age. In this case, the pyloric muscle becomes abnormally thick and narrows the opening, making it difficult for stomach contents to empty into the small intestine. This can lead to symptoms such as vomiting (often projectile), dehydration, and poor weight gain.

The diagnosis of pyloric stenosis is often made through physical examination, ultrasound, or other imaging studies. Treatment typically involves surgery to correct the narrowed opening, known as a pyloromyotomy. This procedure involves making an incision in the pylorus to relieve the obstruction and allow normal stomach emptying.

In some cases, pyloric stenosis can also occur in adults, although this is much less common than in infants. Adult pyloric stenosis can be caused by various factors, including chronic gastritis, peptic ulcers, or previous surgeries. The symptoms and treatment approach for adult pyloric stenosis may differ from those seen in infants.

Disease progression is the worsening or advancement of a medical condition over time. It refers to the natural course of a disease, including its development, the severity of symptoms and complications, and the impact on the patient's overall health and quality of life. Understanding disease progression is important for developing appropriate treatment plans, monitoring response to therapy, and predicting outcomes.

The rate of disease progression can vary widely depending on the type of medical condition, individual patient factors, and the effectiveness of treatment. Some diseases may progress rapidly over a short period of time, while others may progress more slowly over many years. In some cases, disease progression may be slowed or even halted with appropriate medical interventions, while in other cases, the progression may be inevitable and irreversible.

In clinical practice, healthcare providers closely monitor disease progression through regular assessments, imaging studies, and laboratory tests. This information is used to guide treatment decisions and adjust care plans as needed to optimize patient outcomes and improve quality of life.

Rheumatic Heart Disease (RHD) is defined as a chronic heart condition caused by damage to the heart valves due to untreated or inadequately treated streptococcal throat infection (strep throat). The immune system's response to this infection can mistakenly attack and damage the heart tissue, leading to inflammation and scarring of the heart valves. This damage can result in narrowing, leakage, or abnormal functioning of the heart valves, which can further lead to complications such as heart failure, stroke, or infective endocarditis.

RHD is a preventable and treatable condition if detected early and managed effectively. It primarily affects children and young adults in developing countries where access to healthcare and antibiotics for strep throat infections may be limited. Long-term management of RHD typically involves medications, regular monitoring, and sometimes surgical intervention to repair or replace damaged heart valves.

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.

Discrete subaortic stenosis is a medical condition that refers to a narrowing (stenosis) in the outflow tract below the aortic valve of the heart. This narrowing is usually caused by a fibrous ring or a discrete ridge of tissue that partially obstructs the flow of blood from the left ventricle into the aorta.

Discrete subaortic stenosis can cause various symptoms, including shortness of breath, chest pain, fatigue, and syncope (fainting). In severe cases, it can lead to heart failure or even sudden death. The condition is often diagnosed using echocardiography, which can help evaluate the severity of the narrowing and any associated abnormalities.

Treatment for discrete subaortic stenosis typically involves surgical intervention to remove the obstructive tissue and relieve the obstruction. In some cases, a mechanical valve may be implanted to replace the damaged aortic valve. Regular follow-up care is necessary to monitor for any potential complications or recurrence of the narrowing.

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.

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.

A newborn infant is a baby who is within the first 28 days of life. This period is also referred to as the neonatal period. Newborns require specialized care and attention due to their immature bodily systems and increased vulnerability to various health issues. They are closely monitored for signs of well-being, growth, and development during this critical time.

Cardiac valve annuloplasty is a surgical procedure that involves repairing and reinforcing the ring-like structure (annulus) surrounding the heart valves, primarily the mitral or tricuspid valves. This procedure is often performed to correct valve leaks or regurgitation caused by various conditions such as valve disease or dilated cardiomyopathy.

During the annuloplasty procedure, the surgeon typically uses an artificial ring-like device (annuloplasty ring) made of fabric, metal, or a combination of both to reshape and stabilize the damaged annulus. The ring is sewn in place, reducing the size of the valve opening and helping the valve leaflets to coapt properly, thereby preventing valve leaks and improving heart function.

Annuloplasty can be performed as a standalone procedure or in combination with other cardiac surgeries such as valve replacement or repair. The specific technique and approach may vary depending on the individual patient's needs and the surgeon's preference.

Venous valves are one-way flaps made of thin, flexible tissue that lie inside your veins. They allow blood to flow towards the heart but prevent it from flowing backward. These valves are especially important in the veins of the legs, where they help to counteract the force of gravity and ensure that blood flows back up to the heart. When venous valves become damaged or weakened, blood can pool in the veins, leading to conditions such as varicose veins or chronic venous insufficiency.

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.

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.

Aortic coarctation is a narrowing of the aorta, the largest blood vessel in the body that carries oxygen-rich blood from the heart to the rest of the body. This condition usually occurs in the part of the aorta that is just beyond where it arises from the left ventricle and before it divides into the iliac arteries.

In aortic coarctation, the narrowing can vary from mild to severe, and it can cause a variety of symptoms depending on the severity of the narrowing and the age of the individual. In newborns and infants with severe coarctation, symptoms may include difficulty breathing, poor feeding, and weak or absent femoral pulses (located in the groin area). Older children and adults with mild to moderate coarctation may not experience any symptoms until later in life, when high blood pressure, headaches, nosebleeds, leg cramps, or heart failure develop.

Aortic coarctation is typically diagnosed through physical examination, imaging tests such as echocardiography, CT angiography, or MRI, and sometimes cardiac catheterization. Treatment options include surgical repair or balloon dilation (also known as balloon angioplasty) to open the narrowed section of the aorta. If left untreated, aortic coarctation can lead to serious complications such as high blood pressure, heart failure, stroke, and rupture or dissection of the aorta.

Endocarditis is an inflammation of the inner layer of the heart chambers and heart valves, called the endocardium. This inflammation typically results from a bacterial or, less commonly, fungal infection that travels through the bloodstream and attaches to damaged areas of the heart.

There are two main types of endocarditis:

1. Acute Endocarditis: Develops quickly and can be severe, causing fever, chills, shortness of breath, fatigue, and heart murmurs. It may lead to serious complications like heart failure, embolism (blood clots that travel to other parts of the body), and damage to heart valves.

2. Subacute Endocarditis: Develops more slowly, often causing milder symptoms that can be mistaken for a cold or flu. Symptoms may include fatigue, weakness, fever, night sweats, weight loss, joint pain, and heart murmurs. Subacute endocarditis is more likely to affect people with previously damaged heart valves or congenital heart conditions.

Treatment usually involves several weeks of intravenous antibiotics or antifungal medications, depending on the cause of the infection. In some cases, surgery may be required to repair or replace damaged heart valves. Preventive measures include good oral hygiene and prompt treatment of infections, especially in individuals at a higher risk for endocarditis, such as those with congenital heart defects, artificial heart valves, or previous history of endocarditis.

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.

An aortic aneurysm is a medical condition characterized by the abnormal widening or bulging of the wall of the aorta, which is the largest artery in the body. The aorta carries oxygenated blood from the heart to the rest of the body. When the aortic wall weakens, it can stretch and balloon out, forming an aneurysm.

Aortic aneurysms can occur anywhere along the aorta but are most commonly found in the abdominal section (abdominal aortic aneurysm) or the chest area (thoracic aortic aneurysm). The size and location of the aneurysm, as well as the patient's overall health, determine the risk of rupture and associated complications.

Aneurysms often do not cause symptoms until they become large or rupture. Symptoms may include:

* Pain in the chest, back, or abdomen
* Pulsating sensation in the abdomen
* Difficulty breathing
* Hoarseness
* Coughing or vomiting

Risk factors for aortic aneurysms include age, smoking, high blood pressure, family history, and certain genetic conditions. Treatment options depend on the size and location of the aneurysm and may include monitoring, medication, or surgical repair.

Noonan Syndrome is a genetic disorder that affects various parts of the body and is characterized by distinctive facial features, short stature, heart defects, and developmental delays. It is caused by mutations in genes responsible for regulating cell growth and division. The syndrome is often identified at birth or in early childhood due to its physical manifestations, which may include widely spaced eyes, low-set ears, a short neck, a broad or webbed neck, chest deformities, and pulmonary valve stenosis. Noonan Syndrome affects both sexes and all races equally, with an estimated prevalence of 1 in 1,000 to 1 in 2,500 live births.

Aortic stenosis, subvalvular is a medical condition that refers to the narrowing or obstruction of the outflow tract below the aortic valve in the heart. This abnormal narrowing can be caused by various factors such as a congenital heart defect, a tissue growth, or scarring from previous procedures. As a result, the left ventricle must work harder to pump blood through the narrowed opening, which can lead to thickening of the heart muscle (hypertrophy) and decreased cardiac output. Symptoms may include chest pain, shortness of breath, fatigue, and dizziness or fainting spells. Severe subvalvular aortic stenosis can lead to serious complications such as heart failure or even sudden death, and may require surgical intervention to correct the problem.

A ventricular septal defect (VSD) is a type of congenital heart defect that involves a hole in the wall separating the two lower chambers of the heart, the ventricles. This defect allows oxygenated blood from the left ventricle to mix with deoxygenated blood in the right ventricle, leading to inefficient oxygenation of the body's tissues. The size and location of the hole can vary, and symptoms may range from none to severe, depending on the size of the defect and the amount of blood that is able to shunt between the ventricles. Small VSDs may close on their own over time, while larger defects usually require medical intervention, such as medication or surgery, to prevent complications like pulmonary hypertension and heart failure.

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.

A reoperation is a surgical procedure that is performed again on a patient who has already undergone a previous operation for the same or related condition. Reoperations may be required due to various reasons, such as inadequate initial treatment, disease recurrence, infection, or complications from the first surgery. The nature and complexity of a reoperation can vary widely depending on the specific circumstances, but it often carries higher risks and potential complications compared to the original operation.

Postoperative complications refer to any unfavorable condition or event that occurs during the recovery period after a surgical procedure. These complications can vary in severity and may include, but are not limited to:

1. Infection: This can occur at the site of the incision or inside the body, such as pneumonia or urinary tract infection.
2. Bleeding: Excessive bleeding (hemorrhage) can lead to a drop in blood pressure and may require further surgical intervention.
3. Blood clots: These can form in the deep veins of the legs (deep vein thrombosis) and can potentially travel to the lungs (pulmonary embolism).
4. Wound dehiscence: This is when the surgical wound opens up, which can lead to infection and further complications.
5. Pulmonary issues: These include atelectasis (collapsed lung), pneumonia, or respiratory failure.
6. Cardiovascular problems: These include abnormal heart rhythms (arrhythmias), heart attack, or stroke.
7. Renal failure: This can occur due to various reasons such as dehydration, blood loss, or the use of certain medications.
8. Pain management issues: Inadequate pain control can lead to increased stress, anxiety, and decreased mobility.
9. Nausea and vomiting: These can be caused by anesthesia, opioid pain medication, or other factors.
10. Delirium: This is a state of confusion and disorientation that can occur in the elderly or those with certain medical conditions.

Prompt identification and management of these complications are crucial to ensure the best possible outcome for the patient.

X-ray computed tomography (CT or CAT scan) is a medical imaging method that uses computer-processed combinations of many X-ray images taken from different angles to produce cross-sectional (tomographic) images (virtual "slices") of the body. These cross-sectional images can then be used to display detailed internal views of organs, bones, and soft tissues in the body.

The term "computed tomography" is used instead of "CT scan" or "CAT scan" because the machines take a series of X-ray measurements from different angles around the body and then use a computer to process these data to create detailed images of internal structures within the body.

CT scanning is a noninvasive, painless medical test that helps physicians diagnose and treat medical conditions. CT imaging provides detailed information about many types of tissue including lung, bone, soft tissue and blood vessels. CT examinations can be performed on every part of the body for a variety of reasons including diagnosis, surgical planning, and monitoring of therapeutic responses.

In computed tomography (CT), an X-ray source and detector rotate around the patient, measuring the X-ray attenuation at many different angles. A computer uses this data to construct a cross-sectional image by the process of reconstruction. This technique is called "tomography". The term "computed" refers to the use of a computer to reconstruct the images.

CT has become an important tool in medical imaging and diagnosis, allowing radiologists and other physicians to view detailed internal images of the body. It can help identify many different medical conditions including cancer, heart disease, lung nodules, liver tumors, and internal injuries from trauma. CT is also commonly used for guiding biopsies and other minimally invasive procedures.

In summary, X-ray computed tomography (CT or CAT scan) is a medical imaging technique that uses computer-processed combinations of many X-ray images taken from different angles to produce cross-sectional images of the body. It provides detailed internal views of organs, bones, and soft tissues in the body, allowing physicians to diagnose and treat medical conditions.

Thoracotomy is a surgical procedure that involves making an incision on the chest wall to gain access to the thoracic cavity, which contains the lungs, heart, esophagus, trachea, and other vital organs. The incision can be made on the side (lateral thoracotomy), back (posterolateral thoracotomy), or front (median sternotomy) of the chest wall, depending on the specific surgical indication.

Thoracotomy is performed for various indications, including lung biopsy, lung resection, esophagectomy, heart surgery, and mediastinal mass removal. The procedure allows the surgeon to directly visualize and access the organs within the thoracic cavity, perform necessary procedures, and control bleeding if needed.

After the procedure, the incision is typically closed with sutures or staples, and a chest tube may be placed to drain any accumulated fluid or air from the pleural space around the lungs. The patient will require postoperative care and monitoring in a hospital setting until their condition stabilizes.

Mitral valve annuloplasty is a surgical procedure that involves repairing and reinforcing the mitral valve in the heart, which helps control blood flow between the left atrium and left ventricle. The procedure typically aims to reduce the size of the mitral valve's dilated or stretched opening (annulus) by implanting a prosthetic ring or band around it. This reinforcement helps restore normal valve function, preventing regurgitation or backflow of blood into the atrium during heart contractions.

The procedure is often performed to treat mitral valve regurgitation, which can be caused by various factors such as age-related degenerative changes, infective endocarditis, rheumatic heart disease, or congenital abnormalities. Mitral valve annuloplasty may be done alone or in combination with other cardiac surgeries like mitral valve replacement or repair of the valve leaflets.

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"Balloon aortic valvuloplasty as a bridge to aortic valve surgery for severe aortic stenosis". Interactive CardioVascular and ... In order to reach the aortic valve, a blood vessel is punctured to introduce the catheter and advance it into the aortic valve ... Clinically, the pressure across the aortic valve is reduced, there is increased blood flow, and the area of the aortic valve is ... Rates Following Balloon Aortic Valvuloplasty versus Surgical Valve Repair in Isolated Congenital Aortic Valve Stenosis - A Meta ...
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Garcia, D (2000). "Assessment of Aortic Valve Stenosis Severity". Circulation. 101 (7): 765-771. doi:10.1161/01.cir.101.7.765. ...
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Campbell, M. (September 1968). "Calcific aortic stenosis and congenital bicuspid aortic valves". British Heart Journal. 30 (5 ... Campbell, M. (July 1968). "The natural history of congenital aortic stenosis". British Heart Journal. 30 (4): 514-526. doi: ... with Ralph Kauntze: Campbell, M.; Kauntze, R. (April 1953). "Congenital aortic valvular stenosis". British Heart Journal. 15 (2 ... Campbell, M. (July 1954). "Simple pulmonary stenosis pulmonary valvular stenosis with a closed ventricular septum". British ...
... resulting in systemic circulation failure in babies born with aortic valve stenosis. Fetal aortic valve stenosis can be ... Fetal aortic stenosis is a disorder that occurs when the fetus' aortic valve does not fully open during development. The aortic ... Aortic Valve Stenosis. Retrieved from: http://www.childrenshospital.org/health-topics/conditions/aortic-valve-stenosis Barron, ... Then a 0.014 inch guide wire is passed across the stenosis aortic valve, where a balloon is inflated to stretch the aortic ...
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"Percutaneous Transcatheter Implantation of an Aortic Valve Prosthesis for Calcific Aortic Stenosis". Circulation. 106 (24): ... Following discovery that the balloon aortic valvuloplasty for severe aortic stenosis was not effective in 80% of patients after ... Alain Cribier is best known for performing the world's first transcatheter aortic valve implantation in 2002, the first mitral ... John G. Webb - performed the first transapical transcatheter aortic valve implantation in 2006 Cribier, Alain (November 25, ...
Interpretation of the Electrocardiographic Findings in Calcareous Stenosis of the Aortic Valve. Ann Intern Med. 1939;13(1):143- ... Calcareous Disease of the Aortic Valve: A Study of Two Hundred Twenty-Eight Cases. American Heart Journal. 1939;17(2):138-157 ...
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Other causes include abdominal compartment syndrome, severe aortic valve stenosis, and disorders of the aorta. Constrictive ... Echocardiography can look for ventricular dysfunction, effusions, or valve dysfunction. Measurement of the vena cava during the ...
Aortic valve regurgitation vs aortic valve stenosis Phonocardiograms from normal and abnormal heart sounds The physical ... Aortic regurgitation (AR), also known as aortic insufficiency (AI), is the leaking of the aortic valve of the heart that causes ... Carrel, Thierry (2009-01-01). "Aortic valve and/or aortic root replacement using an aortic homograft". Multimedia Manual of ... murmur may also be present when auscultating the same aortic area. Unless there is concomitant aortic valve stenosis, the ...
The conventional approach for treatment of aortic valve stenosis is surgical replacement of the aortic valve. This procedure ... 2008). Transcatheter valve implantation for patients with aortic stenosis: a position statement from the European Association ... However, TAVI (transcatheter aortic valve implantation) has emerged as a valid alternative for patients in whom conventional ... The repair of a defected mitral valve is a potential future hybrid procedure, that is still dependent on approval of the ...
Stenosis of Bicuspid aortic valve is like the aortic valve stenosis heart murmur. But, one may hear a systolic ejection click ... This will make murmurs in the mitral valve area more pronounced. Systolic Aortic valve stenosis is a crescendo/decrescendo ... In mild aortic stenosis, the crescendo-decrescendo is early peaking. Whereas in severe aortic stenosis, the crescendo is late- ... Defects may be due to narrowing of one or more valves (stenosis), backflow of blood, through a leaky valve (regurgitation), or ...
2010 May;89(5):1443-7. Transcatheter aortic-valve implantation for aortic stenosis in patients who cannot undergo surgery;N ... "Source" of enthusiasm for transcatheter aortic valve implantation; Circulation. 2010 Jul 6;122(1):8-10. Epub 2010 Jun 21. "The ... for performing keyhole valve and aortic surgery; and has been involved from the beginning on the research of percutaneous ... simplified a method for preserving a patient's aortic valve and reimplanting it at the time of surgery so that patients ( ...
Patients with severe aortic stenosis have a narrowed aortic valve that does not allow blood to flow efficiently. As the heart ... Currently, TAVR is for patients with severe aortic stenosis who are high-risk candidates for open heart surgery because of ... With this minimally invasive technique, doctors deployed the new aortic valve through just a small puncture in the femoral ... This cardiovascular technology allows doctors to replace the aortic valve with a catheter procedure instead of open heart ...
... the aortic valve closes. Aortic stenosis most commonly is the result of calcification of the cusps. Other reasons for stenosis ... The aortic valve may need to be replaced because: The valve is leaky (aortic insufficiency, also known as aortic regurgitation ... The valve is narrowed and doesn't open fully (aortic stenosis) Current methods for aortic valve replacement include open-heart ... Aortic stenosis is treated with aortic valve replacement in order to avoid angina, syncope, or congestive heart failure. ...
Aortic valve stenosis is abnormal narrowing of the aortic valve. This results in much greater LV pressures than the aortic ... Aortic valve diseases like aortic stenosis and insufficiency also increase the afterload, whereas mitral valve regurgitation ... Aortic insufficiency (AI) is a condition in which the aortic valve fails to close completely at the end of systolic ejection, ... The magnitude of the pressure gradient is determined by the severity of the stenosis and the flow rate across the valve. Severe ...
October 2008). "Assessing aortic valve area in aortic stenosis by continuity equation: a novel approach using real-time three- ... For example, during a valve replacement surgery the TEE can be used to assess the valve function immediately before repair/ ... and estimate how well the valves open (or do not open in the case of valvular stenosis). The Doppler technique can also be used ... alternative access to the left heart would be retrograde through the aorta and across the aortic valve into the left ventricle ...
... aortic valve replacement or surgical aortic valve replacement for high surgical risk patients with aortic stenosis (PARTNER 1 ... "Transcatheter aortic-valve replacement for inoperable severe aortic stenosis." New England Journal of Medicine 366, no. 18 ( ... "Bicuspid aortic valves are associated with aortic dilatation out of proportion to coexistent valvular lesions." Circulation 102 ... Bavaria is known as a leading figure in clinical trials for catheter-based aortic valve replacement (TAVR), thoracic aortic ...
noted that patients with acquired VWD and aortic stenosis who underwent valve replacement experienced a correction of their ... A form of VWD occurs in patients with aortic valve stenosis, leading to gastrointestinal bleeding (Heyde's syndrome). This form ... "Acquired von Willebrand syndrome in aortic stenosis". The New England Journal of Medicine. 349 (4): 343-9. doi:10.1056/ ... hemostatic abnormalities, but that the hemostatic abnormalities can recur after 6 months when the prosthetic valve is a poor ...

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