Atherosclerosis A form of arteriosclerosis characterized by the deposition of atheromatous plaques containing cholesterol and lipids on the innermost layer of the walls of large and medium-sized arteries. Anesthesiologist A doctor who specializes in the science of anesthesia. Angina Pectoris  The medical term for chest pain due to coronary heart disease. A condition in which the heart muscle doesn't receive enough blood, resulting in pain in the chest. Angiogram  The X-ray pictures that are made of the blood vessels or chambers of the heart by tracing the course of a special fluid (called a contrast medium or dye), that's been injected into the bloodstream. Aorta The large artery that receives blood from the left ventricle of the heart and distributes it to the body. Aortic valve  The heart valve between the left ventricle and the aorta. It has three flaps, or cusps. Arrhythmia (Dysrhythmia) An abnormal rhythm of the heart. Artery  Any one of a series of vessels that carry blood from the heart to the various parts of the body. Atresia  The absence of a normal opening. Atrium  Either one of the two upper chambers of the heart in which blood collects before being passed to the ventricles; also called auricle. Balloon angioplasty A procedure in which a balloon is inserted into a narrowed area of a blood vessel. When the balloon is inflated, the narrowed area is stretched open and then the balloon is removed. Also called balloon dilation angioplasty. Balloon valvuloplasty A procedure in which a balloon is inserted into the opening of a narrowed heart valve. When the balloon is inflated, the valve is stretched open and then the balloon is removed. Blood pressure  The force or pressure exerted by the heart in pumping blood; pressure of the blood in the arteries. Cardiac Pertaining to the heart. Cardiac arrest When the heart stops beating. Cardiac Catheterization The process of examining the heart by introducing a thin tube (catheter) into a vein or artery and passing it into the heart. Cardiology The study of the heart and its functions in health and disease. Cardiovascular Pertaining to the heart and blood vessels. Catheter A thin tube inserted into a vein or artery. Catheterization The process of examining the heart by inserting a thin tube (catheter) into a vein or artery and passing it into the heart. It is done to sample oxygen, measure pressure and make X-ray movies. Congenital heart defect Part of the heart or its major blood vessels that is not formed properly and does not work as it should at birth. Congestive heart failure The inability of the heart to pump out all the blood that returns to it. This results in blood backing up in the veins that lead to the heart. Sometimes fluid builds up in various parts of the body. Coronary arteries Two arteries arising from the aorta. The arteries arch down over the top of the heart, branch and provide blood to the working heart muscle. Coronary Artery Bypass Graft Surgery Surgery to improve blood supply to the heart muscle. It's most often performed when narrowed coronary arteries reduce the flow of oxygen-containing blood to the heart itself. Arteries or veins are taken from another part of the body to channel needed blood flow to the coronary arteries. Coronary Artery Disease Conditions that cause the coronary arteries to narrow so blood flow to the heart muscle is reduced. Cyanosis Blueness of skin caused by a shortage of oxygen in the blood. Diastolic blood pressure The blood pressure inside the arteries when the heart muscle is relaxed. Digoxin A drug often used in treating congestive heart failure. It makes the contraction of the heart muscle stronger, slows the rate of heart beats and helps remove extra fluid from body tissues. It's also used sometimes to treat certain arrhythmias. Diuretic A Drug that increases the rate that urine forms. It promotes the excretion of water and salts. Doppler See ultrasound. Dysrhythmia (Arrhythmia) An abnormal rhythm of the heart. Echocardiography A diagnostic method in which pulses of sound are transmitted into the body. The echoes returning from the surfaces of the heart and other structures are plotted and recorded on electronic equipment. Electrocardiogram (ECG or EKG) A graphic record of electrical impulses produced by the heart. Endocarditis An inflammation of the inner lining of the heart or heart valves. High blood pressure A chronic increase in blood pressure above the normal range. The increase persists over two or more measurements. Hypertension Same as high blood pressure. Hypothermia A procedure that lowers a patient's body temperature during surgery. It stops all blood circulation so the surgeon can safely repair the heart. Mitral valve The heart valve between the left atrium and left ventricle. It has two flaps, or cusps. Myocardial Infarction (Heart Attack) The damaging or death of an area of the heart muscle (myocardium) resulting from a reduced blood supply to that area. Open-heart surgery Surgery done on the opened heart while the bloodstream is diverted through a heart-lung machine. Percutaneous Transluminal Coronary Angioplasty (PTCA) A procedure sometimes used to dilate (widen) narrowed arteries. A catheter with a deflated balloon on its tip is passed into the narrowed artery segment, the balloon is inflated, and the narrowed segment is widened. Plaque Also called atheroma, this is a deposit of fatty (and other) substances in the inner lining of the artery wall characteristic of atherosclerosis. Pulmonary artery The large artery that receives blood from the right ventricle and takes it to the lungs. Pulmonary (pulmonic) valve The heart valve between the right ventricle and the pulmonary artery. It has three flaps, or cusps. Regurgitation The abnormal backward flowing of blood through a valve of the heart. Ross Procedure Pulmonary autograft (patient's own pulmonary valve to aortic valve position) & Pulmonary homograft (cryopreserved human pulmonic valve to pulmonic valve position). Septum One of the muscular walls dividing the two chambers on the left side of the heart from the two chambers on the right. The atrial septum separates the top chambers and the ventricular septum separates the bottom chambers. Stenosis The narrowing or constriction of an opening (such as a heart valve). Systolic blood pressure Pressure inside the arteries when the heart contracts with each beat. Tricuspid valve The heart valve between the right atrium and right ventricle. It has three flaps, or cusps. Ultrasound High-frequency sound vibrations, that a human ear cannot hear, used in medical diagnosis. In pediatric cardiology the ultrasound test includes both echocardiography (shows a picture of the heart) and the Doppler test (analyzes blood flow). Valve An opening, covered by membrane flaps, between two chambers of the heart or between a chamber of the heart and a blood vessel. When it's closed, no blood normally passes through. Vascular Pertaining to the blood vessels. Vein Any one of a series of vessels that carry blood from various parts of the body back to the heart. Ventricle One of the two lower chambers of the heart.