Keywords: Chapter 11, The Heart
Anastomosis
A connection between two blood vessels or hollow organs. It may be congenital, secondary to a pathologic process or surgically created.
Aneurysm
Dilatation of a cardiac chamber or the lumen of an artery.
Angina pectoris
Chest pain caused by cardiac ischemia, usually caused by coronary atherosclerosis or spasm. Angina is typically induced by exertion. Unstable angina refers to cardiac pain that is not related to exertion.
Arrhythmia
Abnormalities of the heart beat. Includes functional abnormalities such as tachycardia, bradycardia, premature ventricular beats, ventricular fibrillation, atrial fibrillation, flutter and heart block.
Aschoff body
A histologic feature of rheumatic carditis. In its typical form it is a granuloma composed of a central area of fibrinoid necrosis surrounded by histocytes. Aschoff bodies heal by scarring.
Atrial septal defects
An opening in the interatrial septum resulting from abnormal development of the heart. Occurs in several forms such as patent formane ovale, ostium secundum defect, ostium primum defect, etc. Small defects are usually asymptomatic, whereas the larger ones may cause shunting of the blood from left to right.
Bacteremia
Appearance of bacteria in the circulation. A continuous bacteremia is a common feature of bacterial endocarditis, but transient bacteremia may result from any bacterial infection or surgical procedures (e.g., tooth extraction)
Beriberi heart disease
Heart failure due to deficiency of vitamin B1 (thiamine).
Calcific aortic stenosis
Narrowing of the aortic orifice due to calcification of the valvular ring and/or valves. May occur in an idiopathic form without any predisposing conditions in the elderly, as an extension of atherosclerosis of the aorta into the aortic valve or as a complication of rheumatic endocarditis.
Carcinoid heart disease
Endocardial fibrosis involving the right atrium and ventricle and tricuspid valve, caused by the biogenic amines (histamine and serotonin) and polypeptide hormones released from carcinoid tumors into the venous circulation. Typically caused by intestinal carcinoid tumors metastatic to the liver.
Cardiac tamponade
Compression of the heart by fluid that has accumulated in the pericardial sac.
Cardiogenic shock
Systemic cardiovascular collapse due to pump failure of the heart.
Cardiomyopathy
Several primary or idiopathic heart diseases involving the myocardium. The diagnosis is typically made by excluding other more common causes of heart failure such as coronary heart disease, hypertension, rheumatic fever, infectious myocarditis. Three forms are recognized: dilated, hypertrophic and restrictive.
Coarctation of the aorta
Congenital constriction of the aorta. Depending on the location of constriction it is classified as either preductal (infantile) and postductal (adult). Post-ductal coarctation is associated with hypertension in the head and arms and hypotension in the parts of the body that receive the blood from the constricted aorta. Such patients also develop extensive arterial anastomoses between the subclavian artery and the aorta distal to the constriction.
Conduction system of the heart
A system of specialized fibers that facilitate the transmission of electric impulses through the heart. Includes sinus-atrial node, atrioventricular node, the bundle of hiss, purkinje fibers and the left and right bundle branches.
Congenital heart disease
A category of diseases related to abnormal development of the heart and major blood vessels. Ventricular septal defect is the most common clinically diagnosed congenital heart disease.
Contraction band necrosis
Necrosis of myocardial cells characterized by the formation of periodic cytoplasmic bands caused by hypercontraction of myofilaments. Typically found at the margins of infarcts or in reperfusion injury.
Cor pulmonale
Right ventricular hypertrophy and failure due to increased pulmonary pressure. May be acute (as in pulmonary saddle embolism) or chronic due to pulmonary disease (e.g. pulmonary fibrosis or left heart failure and mitral disease).
Coronary arteries
Blood vessels supplying the blood to the heart. Include right and left coronary artery. The left coronary has two major branches, left anterior descending and left circumflex. LAD artery provides the blood to the anterior side of the left ventricle and the anterior portion of the interventricular septum. LC artery provides the blood to the lateral side of the ventricle. Right coronary artery provides the heart to the right ventricle, posterior wall of the left ventricle and the posterior part of the interventricular septum.
Dextrocardia
A congenital heart disease characterized by inversion of the cardiac chambers. In this condition the left atrium and ventricle are on the right side and the right atrium and ventricle on the left. It may be associated with situs viscerum inversus.
Diastole
Part of the cardiac cycle during which the myocardial cells relax and the ventricles dilate allowing the blood to flow in.
Dilation of the heart
Widening of the cardiac chambers, usually due to the stretching of the myocytes, may be reversible or irreversible.
Dressler syndrome
A delayed pericarditis that occurs 2-6 weeks following cardiac surgery or myocardial infarction. It responds to steroid treatment and is considered to be immune mediated.
Ductus arteriosus
A fetal blood vessel that connects the pulmonary artery with the aorta allowing the oxygenated blood from the fetal pulmonary artery to bypass the lungs and enter directly into the aorta. It undergoes a closure during the first few days of Postnatal Life.
Ebstein malformation
Congenital heart disease characterized by downward displacement of the abnormal septal leaflet of the tricuspid valve into an underdeveloped right ventricle.
Endocardial fibroelastosis
Thickening of the endocardium of the heart chambers and valves most prominent in the left ventricle. Primary EFE is a congenital disease of unknown etiology. Secondary EFE is a complication of various other cardiac disease characterized by intraventricular hypertension or turbulent blood flow.
Endocarditis
Inflammation of the endocardium. May involve the valves (valvular endocarditis) or the lining of the ventricles (mural endocarditis). Depending on its etiology may be classified as bacterial or nonbacterial (sterile).
Foramen ovale
An opening at the midpoint of the interatrial septum. It is open during fetal life allowing the passage of blood from the right to the left atrium. This natural fetal shunt allows the blood to bypass the fetal lungs. Foramen ovale closes after birth, but remains probe-patent in 25% of children and adults.
Heart failure
Heart dysfunction resulting in the inability of the heart to pump blood into the blood vessels. May be acute or chronic. It may be caused by many diseases affecting the endocardium, myocardium or pericardium, but most often it is a consequence of atherosclerosis affecting the coronary arteries. Clinically it may be classified as right-sided or left-sided; high output or low output.
Hypertension
Elevation of arterial blood pressure over the accepted norms for a given age (normal for adults is 120/80 mm/Hg). Classified as primary or secondary.
Hypertensive heart disease
Heart disease caused by increased blood pressure. Characterized by left ventricular hypertrophy, usually accompanied by relative ischemia of the myocardium. Hypertension also predisposes the arteries to atherosclerosis.
Hypertrophy of the myocardium
Increased thickness of the wall of cardiac chambers. It can involve the left ventricle or the right ventricle or both. The most important causes of left ventricular hypertrophy are arterial hypertension and valvular diseases of the aortic orifice. The most common cause of right ventricular hypertrophy is left ventricular hypertrophy. Right ventricular hypertrophy is a sign of chronic cor pulmonale and it regularly accompanies chronic pulmonary hypertension.
Ischemic heart disease
A group of heart diseases related to circulatory disturbances caused by coronary atherosclerosis and inadequate oxygen supply to the myocardium.
Libman Sacks endocarditis
Sterile immune mediated endocarditis of systemic lupus erythematosus. Most often it involves the mitral valve.
Mitral valve prolapse
Protrusion of the loosened up "floppy" mitral valve leaflets into the left atrium during systole. Usually it asymptomatic but maybe associated with mitral regurgitation.
Myocardial infarct
Ischemic necrosis of a portion of the myocardium, typically caused by coronary artery occlusion, e.g., thrombosis overlying atherosclerotic lesions. If the cause is not known it is callled idiopathic
Myocarditis
Inflammation of the myocardium. May be caused by infectious pathogens (bacteria, viruses, protozoa, etc.) toxins (e.g. diphtheria toxin), or immune factors.
Myxoma of the heart
The most common primary benign tumor of the heart. It has a jelly like appearance and is typically located on the atrial side of the mitral valve.
Pancarditis
Inflammation of all parts of the heart. Includes endocarditis, myocarditis and pericarditis.
Patent ductus arteriosus
Congenital defect resulting from incomplete involution and closure of the ductus arteriosus. May be isolated or combined with other congenital defects.
Pericardial effusion
Accumulation of fluid in the pericardial sac in excess of the normal content (50 ml). The fluid may be serous, chylous or hemorrhagic. It may be a sign of pericarditis but also accompanies transmural ruyo cardial infarcts. It may be a part of generilized dema (anasarca).
Pericarditis
Inflammation of the pericardial sac, typically involving the epicardium and pericardium.
Pericarditis, constrictive
Chronic inflammation that obliterates the pericardial cavity. The fibrous tissue encases and compresses the heart preventing its dilation or during diastole.
Rhabdomyoma
Primary benign striated muscle cell tumor of the myocardium, typically found in children.
Rheumatic fever
A hypersensitivity disease typically caused by an abnormal immune response to streptococcal antigens. Includes carditis, arthritis, chorea, erythema marginatum and subcutaneous nodules (Jones major criteria), and a variety of other signs of systemic inflammatory disease.
Rheumatic heart disease
Cardiac manifestation of rheumatic fever. Includes acute and chronic endocarditis, myocarditis and pericarditis.
Stenosis
Narrowing of the lumen of a blood vessel or ostium (orifice) of the cardiac chambers.
Systole
Part of the cardiac cycle during which the ventricles contract and eject the blood into the pulmonary artery and the aorta.
Tetralogy of Fallot
Complex congenital heart malformation that comprises pulmonary stenosis, ventricular septal defect, dextroposition of the aorta and right ventricular hypertrophy. It is the most common cyanotic congenital heart disease.
Transposition of great arteries
Congenital heart disease in which the aorta and the pulmonary artery are transposed: the aorta arises from the right ventricule and the pulmonary artery from the left ventricle. It presents with cyanosis of early onset.
Truncus arteriosus
Congenital malformation in which the pulmonary artery and aorta are not separated one from another but form a common vessel. Also known as persistent truncus arteriosus, referring to the fact that in early embryonic life the aorta and the pulmonary artery arise from a common precursor truncus, which subsequently divides into two distinct arteries.
Ventricular septal defect
Congenital abnormality characterized by an opening in the connective tissue (membranous) or muscular part of the interventricular septum. It may occur as an isolated defect or as part of complex cardiac malformations such as tetralogy of Fallot or endocardial cushion defects.