The valve between the left ventricle and the ascending aorta which prevents backflow into the left ventricle.

The valve between the left atrium and left ventricle of the heart.

Pathological conditions involving any of the various HEART VALVES and the associated structures (PAPILLARY MUSCLES and CHORDAE TENDINEAE).

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.

A valve situated at the entrance to the pulmonary trunk from the right ventricle.

The valve consisting of three cusps situated between the right atrium and right ventricle of the heart.

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).

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.

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.

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.

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.

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.

Backflow of blood from the RIGHT VENTRICLE into the RIGHT ATRIUM due to imperfect closure of the TRICUSPID VALVE.

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.

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.

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.

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.

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 plan and delineation of prostheses in general or a specific prosthesis.

Procedures in which placement of CARDIAC CATHETERS is performed for therapeutic or diagnostic procedures.

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.

Ultrasonic recording of the size, motion, and composition of the heart and surrounding tissues using a transducer placed in the esophagus.

Ultrasonic recording of the size, motion, and composition of the heart and surrounding tissues. The standard approach is transthoracic.

Pathologic deposition of calcium salts in tissues.

The valve, at the junction of the CECUM with the COLON, that guards the opening where the ILEUM enters the LARGE INTESTINE.

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.

Surgery performed on the heart.

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.

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.

Malfunction of implantation shunts, valves, etc., and prosthesis loosening, migration, and breaking.

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.

A repeat operation for the same condition in the same patient due to disease progression or recurrence, or as followup to failed previous surgery.

Echocardiography applying the Doppler effect, with the superposition of flow information as colors on a gray scale in a real-time image.

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)

Developmental abnormalities involving structures of the heart. These defects are present at birth but may be discovered later in life.

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.

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.

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.

Elements of limited time intervals, contributing to particular results or situations.

Techniques for securing together the edges of a wound, with loops of thread or similar materials (SUTURES).

The movement and the forces involved in the movement of the blood through the CARDIOVASCULAR SYSTEM.

A fetal heart structure that is the bulging areas in the cardiac septum between the HEART ATRIA and the HEART VENTRICLES. During development, growth and fusion of endocardial cushions at midline forms the two atrioventricular canals, the sites for future TRICUSPID VALVE and BICUSPID VALVE.

Act of listening for sounds within the heart.

Widening of a stenosed HEART VALVE by the insertion of a balloon CATHETER into the valve and inflation of the balloon.

An abnormal balloon- or sac-like dilatation in the wall of AORTA.

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.

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.

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.

Levels within a diagnostic group which are established by various measurement criteria applied to the seriousness of a patient's disorder.

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.

Infections resulting from the implantation of prosthetic devices. The infections may be acquired from intraoperative contamination (early) or hematogenously acquired from other sites (late).

Obstruction of a blood vessel (embolism) by a blood clot (THROMBUS) in the blood stream.

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.

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.

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.

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.

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.

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.

Methods of creating machines and devices.

The chambers of the heart, to which the BLOOD returns from the circulation.

The sounds heard over the cardiac region produced by the functioning of the heart. There are four distinct sounds: the first occurs at the beginning of SYSTOLE and is heard as a "lubb" sound; the second is produced by the closing of the AORTIC VALVE and PULMONARY VALVE and is heard as a "dupp" sound; the third is produced by vibrations of the ventricular walls when suddenly distended by the rush of blood from the HEART ATRIA; and the fourth is produced by atrial contraction and ventricular filling.

The protrusion of an organ or part of an organ into a natural or artificial orifice.

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.

A benign tumor of fibrous or fully developed connective tissue.

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)

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).

The condition of an anatomical structure's being dilated beyond normal dimensions.

Surgery performed on the heart or blood vessels.

Removal of an implanted therapeutic or prosthetic device.

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.

Devices, usually incorporating unidirectional valves, which are surgically inserted in the sclera to maintain normal intraocular pressure.

Downward displacement of any one of the HEART VALVES from its normal position. This usually results in failed valve closure.

The fitting and adjusting of artificial parts of the body. (From Stedman's, 26th ed)

The innermost layer of the heart, comprised of endothelial cells.

The vein accompanying the femoral artery in the same sheath; it is a continuation of the popliteal vein and becomes the external iliac vein.

Types of spiral computed tomography technology in which multiple slices of data are acquired simultaneously improving the resolution over single slice acquisition technology.

Surgical incision into the chest wall.

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.

Studies to determine the advantages or disadvantages, practicability, or capability of accomplishing a projected plan, study, or project.

The amount of BLOOD pumped out of the HEART per beat, not to be confused with cardiac output (volume/time). It is calculated as the difference between the end-diastolic volume and the end-systolic volume.

The 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.

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.

One of the protein CROSS-LINKING REAGENTS that is used as a disinfectant for sterilization of heat-sensitive equipment and as a laboratory reagent, especially as a fixative.

Conical muscular projections from the walls of the cardiac ventricles, attached to the cusps of the atrioventricular valves by the chordae tendineae.

Blocking of a blood vessel by an embolus which can be a blood clot or other undissolved material in the blood stream.

The period following a surgical operation.

The dilatation of the aortic wall behind each of the cusps of the aortic valve.

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.

Agents that prevent clotting.

A value equal to the total volume flow divided by the cross-sectional area of the vascular bed.

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)

General or unspecified injuries to the heart.

Formation and development of a thrombus or blood clot in the blood vessel.

Pathological conditions involving the HEART including its structural and functional abnormalities.

Any of various animals that constitute the family Suidae and comprise stout-bodied, short-legged omnivorous mammals with thick skin, usually covered with coarse bristles, a rather long mobile snout, and small tail. Included are the genera Babyrousa, Phacochoerus (wart hogs), and Sus, the latter containing the domestic pig (see SUS SCROFA).

Making an incision in the STERNUM.

Impaired venous blood flow or venous return (venous stasis), usually caused by inadequate venous valves. Venous insufficiency often occurs in the legs, and is associated with EDEMA and sometimes with VENOUS STASIS ULCERS at the ankle.

Motion picture study of successive images appearing on a fluoroscopic screen.

The heart of the fetus of any viviparous animal. It refers to the heart in the postembryonic period and is differentiated from the embryonic heart (HEART/embryology) only on the basis of time.

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).

Restoration of an organ or other structure to its original site.

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.

The co-occurrence of pregnancy and a cardiovascular disease. The disease may precede or follow FERTILIZATION and it may or may not have a deleterious effect on the pregnant woman or FETUS.

The main trunk of the systemic arteries.

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.

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.

A vital statistic measuring or recording the rate of death from any cause in hospitalized populations.

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.

A distribution in which a variable is distributed like the sum of the squares of any given independent random variable, each of which has a normal distribution with mean of zero and variance of one. The chi-square test is a statistical test based on comparison of a test statistic to a chi-square distribution. The oldest of these tests are used to detect whether two or more population distributions differ from one another.

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.

Tomography using x-ray transmission and a computer algorithm to reconstruct the image.

Criteria and standards used for the determination of the appropriateness of the inclusion of patients with specific conditions in proposed treatment plans and the criteria used for the inclusion of subjects in various clinical trials and other research protocols.

Cardiac manifestation of gastrointestinal CARCINOID TUMOR that metastasizes to the liver. Substances secreted by the tumor cells, including SEROTONIN, promote fibrous plaque formation in ENDOCARDIUM and its underlying layers. These deposits cause distortion of the TRICUSPID VALVE and the PULMONARY VALVE eventually leading to STENOSIS and valve regurgitation.

Hand-held tools or implements used by health professionals for the performance of surgical tasks.

A device designed to stimulate, by electric impulses, contraction of the heart muscles. It may be temporary (external) or permanent (internal or internal-external).

Generating tissue in vitro for clinical applications, such as replacing wounded tissues or impaired organs. The use of TISSUE SCAFFOLDING enables the generation of complex multi-layered tissues and tissue structures.

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.

Radiography of the heart and great vessels after injection of a contrast medium.

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.

An anticoagulant that acts by inhibiting the synthesis of vitamin K-dependent coagulation factors. Warfarin is indicated for the prophylaxis and/or treatment of venous thrombosis and its extension, pulmonary embolism, and atrial fibrillation with embolization. It is also used as an adjunct in the prophylaxis of systemic embolism after myocardial infarction. Warfarin is also used as a rodenticide.

Pathological processes involving any part of the AORTA.

A pathological process consisting of hardening or fibrosis of an anatomical structure, often a vessel or a nerve.

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.

Polyester polymers formed from terephthalic acid or its esters and ethylene glycol. They can be formed into tapes, films or pulled into fibers that are pressed into meshes or woven into fabrics.

The short wide vessel arising from the conus arteriosus of the right ventricle and conveying unaerated blood to the lungs.

The graphic recording of chest wall movement due to cardiac impulses.

Failure of equipment to perform to standard. The failure may be due to defects or improper use.

A purely physical condition which exists within any material because of strain or deformation by external forces or by non-uniform thermal expansion; expressed quantitatively in units of force per unit area.

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.

A type of stress exerted uniformly in all directions. Its measure is the force exerted per unit area. (McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)

Impaired impulse conduction from HEART ATRIA to HEART VENTRICLES. AV block can mean delayed or completely blocked impulse conduction.

Animals produced by the mating of progeny over multiple generations. The resultant strain of animals is virtually identical genotypically. Highly inbred animal lines allow the study of certain traits in a relatively pure form. (Segen, Dictionary of Modern Medicine, 1992)

A congenital cardiovascular malformation in which the AORTA arises entirely from the RIGHT VENTRICLE, and the PULMONARY ARTERY arises from the LEFT VENTRICLE. Consequently, the pulmonary and the systemic circulations are parallel and not sequential, so that the venous return from the peripheral circulation is re-circulated by the right ventricle via aorta to the systemic circulation without being oxygenated in the lungs. This is a potentially lethal form of heart disease in newborns and infants.

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.

The process by which a tissue or aggregate of cells is kept alive outside of the organism from which it was derived (i.e., kept from decay by means of a chemical agent, cooling, or a fluid substitute that mimics the natural state within the organism).

A group of diseases in which the dominant feature is the involvement of the CARDIAC MUSCLE itself. Cardiomyopathies are classified according to their predominant pathophysiological features (DILATED CARDIOMYOPATHY; HYPERTROPHIC CARDIOMYOPATHY; RESTRICTIVE CARDIOMYOPATHY) or their etiological/pathological factors (CARDIOMYOPATHY, ALCOHOLIC; ENDOCARDIAL FIBROELASTOSIS).

Method of measuring performance against established standards of best practice.

The proportion of survivors in a group, e.g., of patients, studied and followed over a period, or the proportion of persons in a specified group alive at the beginning of a time interval who survive to the end of the interval. It is often studied using life table methods.

A nonparametric method of compiling LIFE TABLES or survival tables. It combines calculated probabilities of survival and estimates to allow for observations occurring beyond a measurement threshold, which are assumed to occur randomly. Time intervals are defined as ending each time an event occurs and are therefore unequal. (From Last, A Dictionary of Epidemiology, 1995)

A procedure to stop the contraction of MYOCARDIUM during HEART SURGERY. It is usually achieved with the use of chemicals (CARDIOPLEGIC SOLUTIONS) or cold temperature (such as chilled perfusate).

The hollow, muscular organ that maintains the circulation of the blood.

Artificial substitutes for body parts, and materials inserted into tissue for functional, cosmetic, or therapeutic purposes. Prostheses can be functional, as in the case of artificial arms and legs, or cosmetic, as in the case of an artificial eye. Implants, all surgically inserted or grafted into the body, tend to be used therapeutically. IMPLANTS, EXPERIMENTAL is available for those used experimentally.

Bleeding or escape of blood from a vessel.

Period of contraction of the HEART, especially of the HEART VENTRICLES.

Infections with bacteria of the genus STAPHYLOCOCCUS.

System established by the World Health Organization and the International Committee on Thrombosis and Hemostasis for monitoring and reporting blood coagulation tests. Under this system, results are standardized using the International Sensitivity Index for the particular test reagent/instrument combination used.

The arterial trunk arising from the fetal heart. During development, it divides into AORTA and the PULMONARY ARTERY.

Death resulting from the presence of a disease in an individual, as shown by a single case report or a limited number of patients. This should be differentiated from DEATH, the physiological cessation of life and from MORTALITY, an epidemiological or statistical concept.

Tubes inserted to create communication between a cerebral ventricle and the internal jugular vein. Their emplacement permits draining of cerebrospinal fluid for relief of hydrocephalus or other condition leading to fluid accumulation in the ventricles.

Accumulation of purulent material in tissues, organs, or circumscribed spaces, usually associated with signs of infection.

The hemodynamic and electrophysiological action of the right HEART VENTRICLE.

Post-systolic relaxation of the HEART, especially the HEART VENTRICLES.

Production of an image when x-rays strike a fluorescent screen.

An infant during the first month after birth.

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.

Motion pictures of the passage of contrast medium through blood vessels.

The return of a sign, symptom, or disease after a remission.

The evaluation of incidents involving the loss of function of a device. These evaluations are used for a variety of purposes such as to determine the failure rates, the causes of failures, costs of failures, and the reliability and maintainability of devices.

A pathological constriction occurring in the region below the AORTIC VALVE. It is characterized by restricted outflow from the LEFT VENTRICLE into the AORTA.

Embolism or thrombosis involving blood vessels which supply intracranial structures. Emboli may originate from extracranial or intracranial sources. Thrombosis may occur in arterial or venous structures.

Connective tissue comprised chiefly of elastic fibers. Elastic fibers have two components: ELASTIN and MICROFIBRILS.

Age as a constituent element or influence contributing to the production of a result. It may be applicable to the cause or the effect of a circumstance. It is used with human or animal concepts but should be differentiated from AGING, a physiological process, and TIME FACTORS which refers only to the passage of time.