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Glossary
anemia—A deficiency in the oxygen-carrying material of the blood.
aneurysm—A sac or out-pouching of the walls of an artery or vein filled with blood.
angina pectoris—Chest discomfort (usually described as pressure or pain) occurring beneath the breastbone when the heart is not getting enough oxygen. Typically, it occurs with exercise or emotional stress, lasts only a few minutes, and goes away with rest. Angina pectoris, or simply "angina," results when blood flow to the heart muscle is inadequate because heart arteries have been narrowed by cholesterol deposits or when there is an imbalance between oxygen demand and oxygen supply caused by hypertension or valvular disease.
angiography—A test to determine the severity and location of blocked arteries of any part of the body, particularly the heart arteries.
angioplasty—See percutaneous transluminal coronary angioplasty (PTCA).
arrhythmia—See cardiac arrhythmia.
artery—A vessel that carries blood away from the heart. Arteries generally carry oxygenated blood. In mammals, the exception is the pulmonary artery, which carries deoxygenated blood to the lungs.
atherosclerosis—A gradual process that occurs when cholesterol collects under the inner lining of artery walls due to damage from uncontrolled high blood pressure, smoking, diabetes, or high blood cholesterol. The deposits (cholesterol plaques) eventually result in fibrosis and calcification, which may narrow or block the artery and hinder blood flow. Also called "hardening of the arteries," the disease can produce angina pectoris, heart attack, or stroke.
atrial fibrillation—See fibrillation.
blood lipid analyses—Tests to measure the level of fats in the blood—such as total cholesterol, low-density "bad" cholesterol (LDL), high-density "good" lipoprotein (HDL) cholesterol, and triglycerides (TG). Abnormal levels of these blood fats can indicate risk of ischemic heart disease. Blood lipid measurements should begin early in life, preferably in the preteen years, especially if there is family history of atherosclerosis. Blood lipid analyses should be performed after a 12-hour fast
blood pressure measurement—A measure of the force of blood flow against artery walls. The measurement is taken with an instrument consisting of an inflatable cuff, inflating bulb, and a gauge (called a sphygmomanometer). The sphygmomanometer is placed around the upper arm and measures blood pressure as it flows through the arteries. Many automated devices are available so patients can measure blood pressure at home.
bradycardia—A type of arrhythmia during which the heart beats in a slow rhythm.
bypass surgery—See coronary artery bypass graft (CABG) surgery.
calcification—A process that occurs when tissue or noncellular material in the body becomes hardened by deposits of calcium salts.
cardiac arrhythmia—Irregularity of the heartbeat caused by damage to or defect in the heart tissue and its electrical system. Three common types of arrhythmia are: 1) very rapid ventricular contractions (tachycardia) that don’t pump enough blood flow to other organs; 2) an excessively slow heartbeat (bradychardia); or 3) most common, extra or "premature" beats.
cardiac catheterization—The process of passing a flexible tube or catheter into the heart through a vein or an artery to withdraw samples of blood, measure pressures within the heart chambers or vessels, and inject X-ray contrast materials to view the heart. Cardiac catheterization is used to evaluate congenital heart disease and ischemic heart disease.
cardiomyopathy—A disorder that appears in several forms and results in weakening of the heart muscles. The heart enlarges, its chambers become enlarged, and the left ventricular wall becomes thin. Cardiomyopathy may be caused by viruses, alcohol, or an inherited defect.
cardiac transplantation—Replacement of a damaged or diseased heart with a healthy heart from a donor who has died of other causes. Patients who have end-stage heart disease but who have good function of other vital organs may be candidates for transplantation of a donor heart. Each year, only 2,000–2,500 hearts become available, but as many as 35,000 patients each year may be on waiting lists for donor hearts for transplantation. Cardiac transplantation surgery has become routine in medical centers specializing in the field, with one- and five-year survival rates topping 70 percent.
cardiomyopathy—This is the general term for diseases of the heart muscle. The most common of these diseases is the dilated cardiomyopathy in which the disease weakens the heart muscle and causes left ventricular dilation leading to increased diastolic pressure and volume.
catheter ablation—An invasive procedure used to treat rapid heart beats, especially in Wolff-Parkinson-White (WPW) syndrome. In WPW syndrome, an abnormal conduction pathway between the atria and the ventricles causes electrical impulses to pass rapidly to the ventricles, creating rapid cardiac arrhythmias. A physician guides a catheter with an electrode at its tip to the area of heart muscle where there is abnormal electrical activity. The cardiovascular specialist delivers a painless radiofrequency impulse that eliminates a tiny area of muscle cells, abolishing the "short circuit" that was causing the rapid heartbeats. Catheter ablation can be used to treat other types of arrhythmias as well. Catheter ablation is also called radiofrequency ablation.
cerebrovascular accident—See stroke.
cholesterol—A type of lipid (fat) used by the body to build cells and certain hormones; also one of the fats found in foods derived from animal sources.
clogged Arteries—Another term for coronary artery disease in which arteries supplying blood to the heart muscle are partially or completely blocked by collections of cholesterol and abnormal blood cells in the artery walls.
congenital heart disease/defects—A range of mild to serious heart abnormalities existing at birth. Congenital heart disease, which can be caused by heredity or by damage to the developing fetus, often involves malformations of the heart valves or abnormal blood flow between the right and the left heart chambers.
congestive heart failure (CHF)—A potentially lethal condition produced by a heart attack, poorly controlled hypertension, or cardiomyopathy. If the left chambers of the heart fail, then blood backs up into the lungs, causing congestion there. If the right chambers of the heart fail, then blood backs up into the legs and the liver, causing congestion and swelling (called edema). Often, both sides fail simultaneously. Most forms of heart disease, including valvular and pericardial disease, eventually lead to congestive heart failure. Some forms of congestive heart disease damage the blood vessels causing "cor pulmonale."
coronary angiography—An X-ray movie of the heart arteries that uses X-ray contrast material. The X-ray is taken after inserting a catheter into an artery at the groin or elbow and guiding it through the aorta and then into a coronary artery, where the contrast agent is injected. The contrast agent makes the artery—and any obstructions or abnormalities—visible on the X-ray image. A similar process can be used to obtain an image of the mitral and aortic valves and the functioning of the left side of the heart.
coronary artery bypass graft (CABG) surgery—A type of operation used to restore normal blood flow to the heart muscle when arteries that supply blood to the heart are blocked or narrowed. CABG surgery involves taking a short length of blood vessel—often a vein from the thigh or the lower leg or the internal mammary artery beneath the breastbone—and using it to connect the diseased blood vessel beyond the blockage site. CABG is the most common major surgery performed in the United States; three-fourths of patients today are still active 15 years after surgery. See also open-heart surgery.
coronary artery disease—See ischemic heart disease.
coronary care unit (CCU)—During heart emergencies, patients should be taken to a hospital coronary unit, or a CCU, for constant supervision by instruments and nursing staff and continuous electrocardiogram, ECG, monitoring. This type of monitoring often includes continuous computerized analysis and an alarm system for abnormal rhythms. In addition, special catheters can be inserted to monitor pressure in the heart and the arteries.
coronary heart disease—See ischemic heart disease.
coronary stent—A slender coil inserted into the blood vessel to prevent it from narrowing. When fatty deposits have built up on the interior walls of the heart arteries, the passages become narrow, blood flow is reduced, and angina pectoris results. Cardiologists perform angioplasty to widen these arteries and restore circulation. After the angioplasty, they may insert coronary stents.
cor pulmonale—Enlargement and eventual failure of the right ventricle of the heart. Cor pulmonale is caused by lung disease. When a lung disease, such as emphysema, destroys lung blood vessels, the right side of the heart must exert more effort to pump blood into the lungs. Eventually, the right ventricle fails.
diabetes mellitus—A metabolic disease caused by an absolute or a relative deficiency of insulin, a hormone that controls how the body processes glucose, protein, and fats. When the body's insulin supply is decreased, it cannot process carbohydrates and it compensates by overprocessing fats and protein. The condition is characterized by chronic high blood sugar and sugar in the urine. Diabetes mellitus can result in coma. Over time, complications can include nerve injury, blindness, kidney failure, and premature atherosclerosis with all of its complications.
ECG—See electrocardiography/electrocardiogram.
echocardiography—A noninvasive cardiac imaging procedure, developed in the 1960s, now widely used to diagnose congenital heart disease, valve disorders (valvular heart disease), weakened heart muscle (cardiomyopathy), fluid around the heart, and other abnormalities or defects. Echocardiography uses an ultrasound machine, which bounces sound waves at tissues of the heart and records an image using the patterns made by reflected sound (or "echoes") from the heart tissue. Echocardiography has been a major advance in managing all types of heart disease.
electrocardiography/electrocardiogram (ECG/EKG)—A method of recording the electrical currents that pass through the heart muscle during each heartbeat. To record a typical ECG, electrodes are attached to the arms and legs, and the electrical pulses are recorded as the patient relaxes on an examining table. The Holter monitor, a portable device, takes a continuous ECG during an extended period and provides physicians with information about a patient’s heart rhythm during a full day of normal activity to aid in detecting rhythm disturbances. Newer devices allow patients to activate a portable recorder whenever they suspect an abnormal heart rhythm. This test is also referred to as an EKG because the procedure was developed in the Netherlands and was first called an "electrokardiogram."
electrophysiologic studies (EPS)—Invasive procedures used to record electrical activity to the heart. In EPS procedures, electrode catheters are guided into the heart chambers to measure how the heart conducts impulses from one area to another so a cardiologist can map the heart’s electrical functioning. EPS procedures are used when an electrocardiogram or other tests are inconclusive in diagnosing a cause for unexplained dizziness, fainting, or palpitations in high-risk patients. The electrodes may be used to trigger or simulate a patient’s abnormal heart rhythms to help define the cause and treatment. Cardiologists may also use the EPS to administer medications and see their effects on the rhythm problem. The EPS procedure can be used to destroy abnormal short circuits in the heart muscle that produce cardiac arrhythmias by applying high frequency radio waves directly on the heart muscle (see catheter ablation).
EPS—See electrophysiologic studies.
external defibrillator—A device used to deliver a direct-current electric shock through the chest wall to restore a normal beat to a heart in ventricular fibrillation.
fibrillation—Abnormal uncontrolled rapid contraction of the fibers in the heart. When the process involves the two upper chambers of the heart (the atria), the condition is called "atrial fibrillation." When it involves the lower, ventricular chambers, the condition is called "ventricular fibrillation."
fibrosis—A process producing scar tissue that forms as a reaction to injury or during a healing process.
heart attack—A medical emergency that occurs when a blood clot forms suddenly in a heart artery and causes a blockage, usually after the surface of cholesterol plaque in the artery breaks. A heart attack, also called a myocardial infarction, usually produces chest pain and shortness of breath. It may also cause sudden death. If nothing is done to reopen the blocked artery, the heart muscle will die and be replaced by scar tissue. More than one million heart attacks occur every year in the United States; it is the leading cause of death from heart disease. Most of these deaths occur outside the hospital.
heart failure—See congestive heart failure.
high blood pressure—A condition that occurs when increased resistance to blood flow through small blood vessels (arterioles) forces the heart to work harder. When the heart has to pump harder, the blood travels through the arteries at a pressure that can damage the inside walls of blood vessels. High blood pressure affects some 50 million Americans, its incidence increases with age, and it is more common among African Americans and older women. High blood pressure can lead to heart, brain, kidney, and eye damage, and it increases the likelihood of stroke and congestive heart failure if is not treated. These risks are significantly reduced with proper treatment. High blood pressure is also called hypertension.
high cholesterol—See hyperlipidemia.
Holter monitor—See electrocardiography/electrocardiogram.
hyperlipidemia—An abnormally large amount of lipids (fats) in the circulating blood. The major components are high-density cholesterol (HDL), also known as good cholesterol; and low-density cholesterol (LDL), also known as bad cholesterol; and triglycerides (TG). Hyperlipidemia is commonly referred to as high cholesterol.
hypertension—See high blood pressure.
implantable cardioverter defibrillator (ICD)—A battery-operated device connected to the heart like a permanent cardiac pacemaker. When the ventricles contract in an uncoordinated manner so that blood is not pumped to the rest of the body, a life-threatening rhythm disturbance (ventricular tachycardia or ventricular fibrillation) results. To prevent a recurrence of this problem, a thoracic surgeon inserts an ICD. Whenever the ICD senses a rhythm disturbance, it delivers a correcting shock inside the heart.
infective endocarditis—Inflammation of the innermost covering of the four valves of the heart (the endocardium). Infective endocarditis is usually caused by bacteria that have lodged on the valve and reproduced. People who have a malformed heart or heart valves are at risk and should use appropriate prophylactic antibiotics (e.g., amoxicillin) during procedures such as dental work. Prolonged intravenous antibiotics are required to treat the disease, and often heart valve surgery is required.
intraaortic balloon pump—A device used when a patient develops shock from a weak heart, usually after an acute heart attack. An intraaortic balloon pump can temporarily support patients and allow time for corrective heart surgery or other treatment.
ischemic heart disease—A serious problem caused by inadequate circulation of blood to the heart muscle. Blood flow to the heart is blocked by obstructions of heart arteries by cholesterol deposits. Ischemic heart disease is the underlying disorder for sudden episodes such as heart attack and sudden death as well as the chronic condition of angina pectoris. Ischemic heart disease is also called coronary artery disease or coronary heart disease.
mitral Valve—Valve that separates the left atrium and the left ventricle and prevents back-flow from the ventricle to the atrium.
myocardial infarction—See heart attack.
nuclear myocardial imaging—A test in which tracer agents (radionuclides) are injected into the blood stream and allowed to travel to the heart. Special cameras can detect the blood flow through the heart and heart-muscle contractions. Other isotopes are detected only in healthy heart muscle, so cardiologists can use them to determine the severity of a heart attack. Imaging abnormalities also may occur during a stress test, allowing the diagnosis of ischemic heart disease to be made from a relatively noninvasive procedure.
open-heart surgery—Any operation in which the chest is opened and a heart-lung machine is used to support the patient while cardiovascular surgeons repair a heart abnormality. Open-heart surgery is used for coronary artery bypass graft (CABG) surgery, congenital defect repairs, and heart valve replacement or repair.
percutaneous transluminal coronary angioplasty (PTCA)—A procedure to open blocked arteries in the heart (or elsewhere in the body). A catheter is inserted into an artery in the leg or the arm and guided into the mouth of a coronary artery. A second, smaller catheter with a balloon at the tip is inserted inside the first one and guided to the obstruction, where the balloon is inflated and deflated to widen that part of the artery and restore blood circulation.
permanent cardiac pacemaker—A surgically implanted device to keep the heart from beating too slowly. Blackouts, fainting, shortness of breath, and other symptoms caused by slowed heartbeat or abnormal rhythm may be treated by implanting a very small, battery-operated pacemaker beneath the skin. Using a wire and an electrode guided to the heart, the device stimulates the right side of the heart. If the pacemaker senses that the heart rate has slowed, it sends electrical impulses that restore a sufficiently fast beat. Some pacemakers increase the heart rate automatically during activity or stress, and most newer models stimulate both the atrial and the ventricular chambers to beat in normal sequence.
prolapse—Floppy valve, associated with regurgitation.
stenosis—See valvular heart disease.
stress test—Studying the heart during exercise to identify the presence of ischemic heart disease or the risk of developing problems while doing strenuous activities. The patient typically walks on a treadmill or peddles a stationary bicycle while connected to an electrocardiograph (ECG) machine. The ECG measures heart rhythms and can suggest when the heart muscle is not receiving adequate blood supply with exertion. To improve its accuracy, a stress test is often accompanied by an imaging technique (nuclear myocardial imaging or echocardiography). In some instances, drugs may be used to simulate heart activity during exercise. The stress test has three primary uses: 1) It is particularly helpful for people with cardiac risk factors who are about to begin an exercise program, 2) it helps cardiologists evaluate chest pain, 3) it can be used to evaluate the benefits of treatment over time.
stroke—A medical event that results from sudden blockage of the blood supply to the brain. The blockage may destroy brain tissue, thereby producing paralysis, loss of speech, loss of consciousness, or other serious abnormalities of the nervous system, on one side of the body.
sudden death—Death that occurs less than one hour from the onset of a cardiac event and is unexpected. Sudden death usually is caused by an abnormal heart rhythm (ventricular fibrillation) that develops during a heart attack. Thanks to modern community emergency medical services, up to one-quarter of such fatalities can be avoided by emergency squads performing external defibrillation before the heart attack victim is transported to the hospital.
tachycardia—Excessively rapid heartbeat.
TIA—See transient ischemic attack.
transient ischemic attack (TIA)—A temporary reduction of blood flow to the brain. Depending on which portion of the brain is deprived of blood, a TIA may result in: 1) vision problems (either a loss of vision or double vision), 2) speech problems (difficulty with speaking or slurring of words), or 3) sensation problems (an arm or a leg may feel clumsy). None of these symptoms lasts for more than a day. Because a third of those who suffer TIA will have a stroke within five years, physicians see TIA as a warning.
valvular heart disease—A heart condition caused when any of the four major valves that regulate the flow of blood through the heart and to the lungs is damaged or diseased. General circulation becomes obstructed (called stenosis) or leaky (called regurgitation), so the volume of blood circulated to the body is limited. The heart must pump harder to move blood forward, and sometimes the blood flows back into the heart. Valvular heart disease is also called heart valve disease.
ventricular fibrillation—See fibrillation.
Wolff-Parkinson White (WPW) Syndrome—A congenital condition during which there is an abnormal tissue connection between the top and the lower cardiac chambers. |
