Mitral Valve: The valve between the left atrium and left ventricle of the heart.Mitral Valve Prolapse: 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.Mitral Valve Insufficiency: 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.Mitral Valve Stenosis: 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.Aortic Valve: The valve between the left ventricle and the ascending aorta which prevents backflow into the left ventricle.Mitral Valve Annuloplasty: 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.Heart Valve Diseases: Pathological conditions involving any of the various HEART VALVES and the associated structures (PAPILLARY MUSCLES and CHORDAE TENDINEAE).Chordae Tendineae: The tendinous cords that connect each cusp of the two atrioventricular HEART VALVES to appropriate PAPILLARY MUSCLES in the HEART VENTRICLES, preventing the valves from reversing themselves when the ventricles contract.Aortic Valve Stenosis: 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.Tricuspid Valve: The valve consisting of three cusps situated between the right atrium and right ventricle of the heart.Heart Valve Prosthesis Implantation: Surgical insertion of synthetic material to repair injured or diseased heart valves.Heart Valve Prosthesis: A device that substitutes for a heart valve. It may be composed of biological material (BIOPROSTHESIS) and/or synthetic material.Aortic Valve Insufficiency: 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).Bioprosthesis: 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.Pulmonary Valve: A valve situated at the entrance to the pulmonary trunk from the right ventricle.Echocardiography, Transesophageal: Ultrasonic recording of the size, motion, and composition of the heart and surrounding tissues using a transducer placed in the esophagus.Rheumatic Heart Disease: 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.Echocardiography: Ultrasonic recording of the size, motion, and composition of the heart and surrounding tissues. The standard approach is transthoracic.Echocardiography, Three-Dimensional: 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)Cardiac Surgical Procedures: Surgery performed on the heart.Cardiac Valve Annuloplasty: 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.Phonocardiography: 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.Endocarditis, Bacterial: 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.Tricuspid Valve Insufficiency: Backflow of blood from the RIGHT VENTRICLE into the RIGHT ATRIUM due to imperfect closure of the TRICUSPID VALVE.Endocarditis: 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.Echocardiography, Doppler, Color: Echocardiography applying the Doppler effect, with the superposition of flow information as colors on a gray scale in a real-time image.Venous Valves: 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.Heart Auscultation: Act of listening for sounds within the heart.Echocardiography, Doppler: 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.Catheterization: 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.Treatment Outcome: 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.Cardiac Catheterization: Procedures in which placement of CARDIAC CATHETERS is performed for therapeutic or diagnostic procedures.Prolapse: The protrusion of an organ or part of an organ into a natural or artificial orifice.Reoperation: A repeat operation for the same condition in the same patient due to disease progression or recurrence, or as followup to failed previous surgery.Myxoma: A benign neoplasm derived from connective tissue, consisting chiefly of polyhedral and stellate cells that are loosely embedded in a soft mucoid matrix, thereby resembling primitive mesenchymal tissue. It occurs frequently intramuscularly where it may be mistaken for a sarcoma. It appears also in the jaws and the skin. (From Stedman, 25th ed)Papillary Muscles: Conical muscular projections from the walls of the cardiac ventricles, attached to the cusps of the atrioventricular valves by the chordae tendineae.Prosthesis Design: The plan and delineation of prostheses in general or a specific prosthesis.Heart Atria: The chambers of the heart, to which the BLOOD returns from the circulation.Heart Rupture: Disease-related laceration or tearing of tissues of the heart, including the free-wall MYOCARDIUM; HEART SEPTUM; PAPILLARY MUSCLES; CHORDAE TENDINEAE; and any of the HEART VALVES. Pathological rupture usually results from myocardial infarction (HEART RUPTURE, POST-INFARCTION).Suture Techniques: Techniques for securing together the edges of a wound, with loops of thread or similar materials (SUTURES).Follow-Up Studies: 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.Heart Neoplasms: Tumors in any part of the heart. They include primary cardiac tumors and metastatic tumors to the heart. Their interference with normal cardiac functions can cause a wide variety of symptoms including HEART FAILURE; CARDIAC ARRHYTHMIAS; or EMBOLISM.Postoperative Complications: 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.Calcinosis: Pathologic deposition of calcium salts in tissues.Heart Ventricles: 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.Kinetocardiography: The graphic recording of chest wall movement due to cardiac impulses.Heart Murmurs: Heart sounds caused by vibrations resulting from the flow of blood through the heart. Heart murmurs can be examined by HEART AUSCULTATION, and analyzed by their intensity (6 grades), duration, timing (systolic, diastolic, or continuous), location, transmission, and quality (musical, vibratory, blowing, etc).Prosthesis Failure: Malfunction of implantation shunts, valves, etc., and prosthesis loosening, migration, and breaking.Cardiopulmonary Bypass: Diversion of the flow of blood from the entrance of the right atrium directly to the aorta (or femoral artery) via an oxygenator thus bypassing both the heart and lungs.Balloon Valvuloplasty: Widening of a stenosed HEART VALVE by the insertion of a balloon CATHETER into the valve and inflation of the balloon.Heart Defects, Congenital: Developmental abnormalities involving structures of the heart. These defects are present at birth but may be discovered later in life.Hemodynamics: The movement and the forces involved in the movement of the blood through the CARDIOVASCULAR SYSTEM.Thoracotomy: Surgical incision into the chest wall.Pulmonary Valve Stenosis: 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.Ventricular Outflow Obstruction: 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.Heart Sounds: The sounds heard over the cardiac region produced by the functioning of the heart. There are four distinct sounds: the first occurs at the beginning of SYSTOLE and is heard as a "lubb" sound; the second is produced by the closing of the AORTIC VALVE and PULMONARY VALVE and is heard as a "dupp" sound; the third is produced by vibrations of the ventricular walls when suddenly distended by the rush of blood from the HEART ATRIA; and the fourth is produced by atrial contraction and ventricular filling.Time Factors: Elements of limited time intervals, contributing to particular results or situations.Severity of Illness Index: Levels within a diagnostic group which are established by various measurement criteria applied to the seriousness of a patient's disorder.Ventricular Function, Left: 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.Atrial Fibrillation: Abnormal cardiac rhythm that is characterized by rapid, uncoordinated firing of electrical impulses in the upper chambers of the heart (HEART ATRIA). In such case, blood cannot be effectively pumped into the lower chambers of the heart (HEART VENTRICLES). It is caused by abnormal impulse generation.Marfan Syndrome: An autosomal dominant disorder of CONNECTIVE TISSUE with abnormal features in the heart, the eye, and the skeleton. Cardiovascular manifestations include MITRAL VALVE PROLAPSE, dilation of the AORTA, and aortic dissection. Other features include lens displacement (ectopia lentis), disproportioned long limbs and enlarged DURA MATER (dural ectasia). Marfan syndrome is associated with mutations in the gene encoding fibrillin, a major element of extracellular microfibrils of connective tissue.Heart Valves: Flaps of tissue that prevent regurgitation of BLOOD from the HEART VENTRICLES to the HEART ATRIA or from the PULMONARY ARTERIES or AORTA to the ventricles.Sternotomy: Making an incision in the STERNUM.Cardiomyopathy, Hypertrophic: A form of CARDIAC MUSCLE disease, characterized by left and/or right ventricular hypertrophy (HYPERTROPHY, LEFT VENTRICULAR; HYPERTROPHY, RIGHT VENTRICULAR), frequent asymmetrical involvement of the HEART SEPTUM, and normal or reduced left ventricular volume. Risk factors include HYPERTENSION; AORTIC STENOSIS; and gene MUTATION; (FAMILIAL HYPERTROPHIC CARDIOMYOPATHY).Retrospective Studies: 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.Surgical Procedures, Minimally Invasive: Procedures that avoid use of open, invasive surgery in favor of closed or local surgery. These generally involve use of laparoscopic devices and remote-control manipulation of instruments with indirect observation of the surgical field through an endoscope or similar device.Heart Injuries: General or unspecified injuries to the heart.Angiocardiography: Radiography of the heart and great vessels after injection of a contrast medium.Thromboembolism: Obstruction of a blood vessel (embolism) by a blood clot (THROMBUS) in the blood stream.Endocardial Cushion Defects: A spectrum of septal defects involving the ATRIAL SEPTUM; VENTRICULAR SEPTUM; and the atrioventricular valves (TRICUSPID VALVE; BICUSPID VALVE). These defects are due to incomplete growth and fusion of the ENDOCARDIAL CUSHIONS which are important in the formation of two atrioventricular canals, site of future atrioventricular valves.Models, Cardiovascular: Theoretical representations that simulate the behavior or activity of the cardiovascular system, processes, or phenomena; includes the use of mathematical equations, computers and other electronic equipment.Pericardium: A conical fibro-serous sac surrounding the HEART and the roots of the great vessels (AORTA; VENAE CAVAE; PULMONARY ARTERY). Pericardium consists of two sacs: the outer fibrous pericardium and the inner serous pericardium. The latter consists of an outer parietal layer facing the fibrous pericardium, and an inner visceral layer (epicardium) resting next to the heart, and a pericardial cavity between these two layers.Stroke Volume: 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.Cardiovascular Surgical Procedures: Surgery performed on the heart or blood vessels.Heart Septum: This structure includes the thin muscular atrial septum between the two HEART ATRIA, and the thick muscular ventricular septum between the two HEART VENTRICLES.Postoperative Period: The period following a surgical operation.Surgical Instruments: Hand-held tools or implements used by health professionals for the performance of surgical tasks.Heart Diseases: Pathological conditions involving the HEART including its structural and functional abnormalities.Prospective Studies: 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.Heart Aneurysm: A localized bulging or dilatation in the muscle wall of a heart (MYOCARDIUM), usually in the LEFT VENTRICLE. Blood-filled aneurysms are dangerous because they may burst. Fibrous aneurysms interfere with the heart function through the loss of contractility. True aneurysm is bound by the vessel wall or cardiac wall. False aneurysms are HEMATOMA caused by myocardial rupture.Rupture, Spontaneous: Tear or break of an organ, vessel or other soft part of the body, occurring in the absence of external force.Diastole: Post-systolic relaxation of the HEART, especially the HEART VENTRICLES.Systole: Period of contraction of the HEART, especially of the HEART VENTRICLES.Cineradiography: Motion picture study of successive images appearing on a fluoroscopic screen.Thoracic Surgery: A surgical specialty concerned with diagnosis and treatment of disorders of the heart, lungs, and esophagus. Two major types of thoracic surgery are classified as pulmonary and cardiovascular.Sternum: A long, narrow, and flat bone commonly known as BREASTBONE occurring in the midsection of the anterior thoracic segment or chest region, which stabilizes the rib cage and serves as the point of origin for several muscles that move the arms, head, and neck.Lutembacher Syndrome: A condition characterized by a combination of OSTIUM SECUNDUM ATRIAL SEPTAL DEFECT and an acquired MITRAL VALVE STENOSIS.Endocardial Fibroelastosis: A condition characterized by the thickening of ENDOCARDIUM due to proliferation of fibrous and elastic tissue, usually in the left ventricle leading to impaired cardiac function (CARDIOMYOPATHY, RESTRICTIVE). It is most commonly seen in young children and rarely in adults. It is often associated with congenital heart anomalies (HEART DEFECTS CONGENITAL;) INFECTION; or gene mutation. Defects in the tafazzin protein, encoded by TAZ gene, result in a form of autosomal dominant familial endocardial fibroelastosis.Device Removal: Removal of an implanted therapeutic or prosthetic device.Heart Septal Defects, Ventricular: 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.Fibroma: A benign tumor of fibrous or fully developed connective tissue.Ventricular Dysfunction, Left: 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.Heart Septal Defects, Atrial: Developmental abnormalities in any portion of the ATRIAL SEPTUM resulting in abnormal communications between the two upper chambers of the heart. Classification of atrial septal defects is based on location of the communication and types of incomplete fusion of atrial septa with the ENDOCARDIAL CUSHIONS in the fetal heart. They include ostium primum, ostium secundum, sinus venosus, and coronary sinus defects.Electrocardiography: Recording of the moment-to-moment electromotive forces of the HEART as projected onto various sites on the body's surface, delineated as a scalar function of time. The recording is monitored by a tracing on slow moving chart paper or by observing it on a cardioscope, which is a CATHODE RAY TUBE DISPLAY.Atrial Function, Left: The hemodynamic and electrophysiological action of the LEFT ATRIUM.Embolism: Blocking of a blood vessel by an embolus which can be a blood clot or other undissolved material in the blood stream.Feasibility Studies: Studies to determine the advantages or disadvantages, practicability, or capability of accomplishing a projected plan, study, or project.Heart Septal Defects: Abnormalities in any part of the HEART SEPTUM resulting in abnormal communication between the left and the right chambers of the heart. The abnormal blood flow inside the heart may be caused by defects in the ATRIAL SEPTUM, the VENTRICULAR SEPTUM, or both.Thrombosis: Formation and development of a thrombus or blood clot in the blood vessel.Tricuspid Valve Prolapse: Abnormal protrusion of one or more of the leaflets of TRICUSPID VALVE into the RIGHT ATRIUM during SYSTOLE. This allows the backflow of blood into right atrium leading to TRICUSPID VALVE INSUFFICIENCY; SYSTOLIC MURMURS. Its most common cause is not primary valve abnormality but rather the dilation of the RIGHT VENTRICLE and the tricuspid annulus.Ileocecal Valve: The valve, at the junction of the CECUM with the COLON, that guards the opening where the ILEUM enters the LARGE INTESTINE.Equipment Design: Methods of creating machines and devices.Coronary Artery Bypass: Surgical therapy of ischemic coronary artery disease achieved by grafting a section of saphenous vein, internal mammary artery, or other substitute between the aorta and the obstructed coronary artery distal to the obstructive lesion.Anemia, Hemolytic: A condition of inadequate circulating red blood cells (ANEMIA) or insufficient HEMOGLOBIN due to premature destruction of red blood cells (ERYTHROCYTES).Blood Flow Velocity: A value equal to the total volume flow divided by the cross-sectional area of the vascular bed.Predictive Value of Tests: 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.Myocardial Contraction: Contractile activity of the MYOCARDIUM.Risk Assessment: 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)Recurrence: The return of a sign, symptom, or disease after a remission.Pulmonary Veins: The veins that return the oxygenated blood from the lungs to the left atrium of the heart.Prosthesis-Related Infections: Infections resulting from the implantation of prosthetic devices. The infections may be acquired from intraoperative contamination (early) or hematogenously acquired from other sites (late).Risk Factors: 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.Sheep: Any of the ruminant mammals with curved horns in the genus Ovis, family Bovidae. They possess lachrymal grooves and interdigital glands, which are absent in GOATS.