Glossary of Terms - Heart Disease and Stroke

adjunctive therapy—Auxiliary treatment that is secondary to the main treatment.

angina pectoris—Chest pain, usually caused by “myocardial ischemia,” a low supply of oxygen to the heart muscle resulting from hardening, narrowing, and sometimes spasm of the coronary arteries.

angioplasty—A technique to open up blocked coronary arteries with a catheter tube.

application submitted—An application for marketing has been submitted by the company to the Food and Drug Administration (FDA).

arrhythmia—Abnormal heart rhythm, usually detected by an electrocardiogram. Arrhythmias can be caused by several factors, such as coronary artery disease, heart valve problems or hyperthyroidism.

arteriosclerosis obliterans—An alternative term for peripheral vascular disease.

atherosclerosis—A common disease in which deposits of plaque containing calcium and fatty substances, such as cholesterol, are formed within the inner layers of the arteries. It is a condition that progresses over decades, chiefly affecting the arteries of the heart, brain and extremities. Its complications include heart attacks and strokes.

atrial fibrillation and atrial flutter— Very fast electrical discharge patterns that make the heart’s atria contract extremely rapidly, which causes the ventricles to contract faster and less efficiently than normal. As a result, inadequate amounts of blood are pumped out of the heart, blood pressure falls, and heart failure may occur.

bradycardia—A slower than normal heart rate. The heart usually beats between 60 and 100 times a minute in an adult at rest. With bradycardia, the heart beats fewer than 60 times per minute. Bradycardia can be a serious problem if the heart doesn’t pump enough oxygen-rich blood to the body. For some people, however, bradycardia doesn’t cause symptoms or complications. An implanted pacemaker and other treatments may correct the disorder.

bypass graft—A vein or artery graft that bypasses blockage in an artery.

cardiac—Of or relating to the heart.

cardiomyopathy—A type of heart disease in which the heart muscle is abnormally enlarged, thickened and/or stiffened. As a result, the heart muscle’s ability to pump blood is usually impaired.

cardiovascular—Of or relating to the heart and blood vessels.

coronary artery disease—A condition caused by atherosclerosis of the arteries that supply the heart.

critical limb ischemia—CLI is a severe obstruction of the arteries that seriously decreases blood flow to the extremities (arms, hands, legs, feet) and has progressed to the point of severe pain and even skin ulcers of sores. The pain, called “rest pain,” caused by CLI can wake up a person at night. CLI is a very severe condition of peripheral arterial disease and needs comprehensive treatment by a vascular surgeon or specialist.

deep vein thrombosis—Blood clotting within the deep-lying veins, often in the legs or pelvic veins.

dyslipidemia—A condition marked by abnormal concentrations of lipids or lipoproteins in the blood.

embolism—The obstruction of a blood vessel by a foreign substance or a blood clot. Foreign substances that can cause embolism include an air bubble, amniotic fluid, a globule of fat, a clump of bacteria, chemicals, and drugs. Blood clots are the most common cause of embolism. The term “embolus” refers to the substance or clot that is obstructing the blood vessel, while “embolism” refers to the process by which that happens.

genotype—The genetic constitution (genome) of a cell, an individual, or an organism. The genotype of a person is her or his genetic makeup. It can pertain to all genes or to a specific gene.

heart attack (myocardial infarction)—A part of the heart muscle (myocardium) dies as a result of blood and oxygen deprivation.

heart failure—The end result of many different types of heart disease. The heart cannot pump blood out normally. This results in congestion (water and salt retention) in the lungs, swelling in the extremities, and reduced blood flow to body tissues.

hemodialysis—A medical procedure that uses a special machine (a dialysis machine) to filter waste products from the blood and to restore normal constituents to it.

hypercholesterolemia—The presence of an abnormally large amount of cholesterol in the cells and plasma of the circulating blood.

hyperlipidemia—A group of metabolic disorders characterized by high levels of lipids (fatty substances, including cholesterol) in the blood. Hyperlipidemia is a risk factor for accelerated atherosclerosis and premature heart attacks.

hyperlipoproteinemia—A metabolic disorder characterized by abnormally elevated concentrations of specific lipoprotein particles in the plasma. Hyperlipidemia (i.e., elevated plasma cholesterol or triglyceride levels or both) is present in all hyperlipoproteinemias.

hyperparathyroidism—Occurs when one or more of the parathyroid glands becomes enlarged and overactive, producing too much parathyroid hormone (PTH). When this happens, the excess parathyroid hormone causes a high level of calcium to be released in the blood. Since the bones are the primary source of this calcium, hyperparathyroidism can result in excess bone loss or osteoporosis. If the condition is successfully treated, the bone loss can usually be reversed and bone density can be restored. Most cases (85 percent) of hyperparathyroidism are the result of a single parathyroid gland malfunctioning and developing into a benign tumor, known as an adenoma. In nearly all other cases (15 percent), two or more glands enlarge, again in a benign fashion, a condition called hyperplasia.

hypertension (high blood pressure)—Persistent elevation of blood pressure above the normal range while the heart is in systolic (contracting) or diastolic (relaxed) mode. Uncontrolled, chronic hypertension strains the heart, damages arteries and creates a greater risk of heart attack, stroke and kidney problems.

hypertriglyceridemia—An elevated triglyceride concentration in the blood.

hyponatremia—Reduced sodium concentration in the blood.

hypotension—A sudden fall in blood pressure. It may be caused by hypovolemia resulting from the excessive use of diuretics, vasodi- lators, or other types of drugs, dehydration, or prolonged bed rest. The disorder may be associated with Addison’s disease, atherosclerosis (build-up of fatty deposits in the arteries), diabetes, and certain neurological disorders. Symptoms, which generally occur after sudden standing, include dizziness, light- headedness, blurred vision, and the temporary loss of consciousness.

hypovolemia—A deficiency in the amount of blood in the body.

hypoxia—An inadequate oxygen supply to the cells and tissues of the body.

imaging agent—A substance used to enhance images of organs and spaces in the body.

intermittent claudication—The most prominent symptom of peripheral arterial disease (PAD). It occurs in one-third to one-half of PAD patients. Claudication refers to the pain that occurs in PAD patients when they exercise, particularly during walking, which is relieved only by rest. Leg pain occurs in one leg in 40 percent of patients and in both legs in 60 percent of patients.

ischemia—Insufficient supply of blood to an organ or tissue, which can cause organ damage such as an ischemic stroke. lipids—A group of fatty substances that includes triglycerides (the principal forms of fat in body fat), phospholipids (important constituents of cell membranes), and sterols (such as cholesterol).

peripheral vascular disease—The obstruction of blood supply to the extremities, particularly the legs, caused by atherosclerosis. Phase 0—First-in-human trials conducted in accordance with FDA’s 2006 guidance on exploratory Investigational New Drug (IND) studies designed to speed up development of promising drugs by establishing very early on whether the agent behaves in human subjects as was anticipated from preclinical studies.

Phase I—Safety testing and pharmacological profiling in humans.

Phase II—Effectiveness testing in humans.

Phase III—Extensive clinical trials in humans.

pulmonary hypertension—High blood pressure in the arteries supplying the lungs due to increased resistance to blood flow through the lungs.

Raynaud’s disease—A circulatory disorder caused by insufficient blood supply to the hands and feet, resulting in cyanosis, numbness, pain, and, in extreme cases, gangrene.

reperfusion injury—Refers to myocardial, vascular, or electro- physiological dysfunction that is induced by the restoration of blood flow to previously ischemic tissue.

restenosis—A condition where an artery plugs up again following treatment to open it up.

stent—A metal device that is used to hold tissue in place. For example, a stent can keep blood vessels open after a surgical procedure or heart catheterization.

stroke—Usually caused by atherosclerosis. It results in death or serious brain damage, such as paralysis or loss of speech. An ischemic stroke is caused by blocked or narrowed arteries that prevent sufficient blood and oxygen from reaching the brain.

subarachnoid hemorrhage— Abnormal, severe discharge of blood below or under the arachnoid membrane and the pia matter of the covering of the brain.

supraventricular tachycardia—An abnormally fast but regular heart rate that occurs in intermittent episodes lasting for several hours or days. It is caused by abnormal electrical impulses arising within the upper chambers of the heart taking over control of the heart beat from the heart’s pacemaker (sinoatrial node).

systemic sclerosis—A rare chronic disease of unknown cause characterized by diffuse fibrosis, degenerative changes, and vascular abnormalities in the skin, joints, and internal organs (especially the esophagus, lower GI tract, lung, heart, and kidney). Common symptoms include Raynaud’s syndrome, heart- burn, and swelling and eventually skin tightening and contractures of the fingers. Lung, heart, and kidney involvement accounts for most deaths. Systemic sclerosis is about four times more common among women than men. It is most common in the third to fifth decades of life and is rare in children.

thromboembolism—Blockage of a blood vessel by a fragment that has broken off and been carried from a thrombus (blood clot) elsewhere in the circulation.

thrombosis—The formation of a blood clot within the heart or a blood vessel.

vasospasm—A sudden constriction of a blood vessel that reduces the blood flow.