Abdomen
The area of the body between the bottom of the ribs and the top of the thighs.
Abdominal aorta
The portion of the aorta in the abdomen.
Ablation
Elimination or removal.
ACE (angiotensin-converting enzyme) inhibitor
A medicine that lowers blood pressure by interfering with the breakdown of a protein-like substance involved in blood pressure regulation.
Acetylcholine
A type of chemical (called a neurotransmitter) that transmits messages among nerve cells and muscle cells.
Acquired heart disease
Heart disease that arises after birth, usually from infection or through the build-up of fatty deposits in the arteries that feed the heart muscle.
Alveoli
Air sacs in the lungs where oxygen and carbon dioxide are exchanged.
Amiodarone
A kind of medicine (called an antiarrhythmic) used to treat irregular heart rhythms such as atrial fibrillation and ventricular tachycardia. It works by regulating nerve impulses in your heart. Amiodarone is mainly given to patients who have not responded to other antiarrhythmic medicines.
Aneurysm
A sac-like protrusion from a blood vessel or the heart, resulting from a weakening of the vessel wall or heart muscle.
Angina or angina pectoris
Chest pain that occurs when diseased blood vessels restrict blood flow to the heart.
Angiography
An x-ray technique in which dye is injected into the chambers of your heart or the arteries that lead to your heart (the coronary arteries). The test lets doctors measure the blood flow and blood pressure in the heart chambers and see if the coronary arteries are blocked.
Angioplasty
A nonsurgical technique for treating diseased arteries by temporarily inflating a tiny balloon inside an artery.
Angiotensin II receptor blocker
A medicine that lowers blood pressure by blocking the action of angiotensin II, a chemical in the body that causes the blood vessels to tighten (constrict).
Annulus
The ring around a heart valve where the valve leaflet merges with the heart muscle.
Antiarrhythmics
Medicines used to treat patients who have irregular heart rhythms.
Anticoagulant
Any medicine that keeps blood from clotting; a blood thinner.
Antihypertensive
Any medicine or other therapy that lowers blood pressure.
Antiplatelet therapy
Medicines that stop blood cells (called platelets) from sticking together and forming a blood clot.
Aorta
The largest artery in the body and the main vessel to supply blood from the heart.
Aortic valve
The valve that regulates blood flow from the heart into the aorta.
Aphasia
The inability to speak, write, or understand spoken or written language because of brain injury or disease.
Arrhythmia (or dysrhythmia)
An abnormal heartbeat.
Arrhythmogenic right ventricular dysplasia (ARVD)
ARVD is a type of cardiomyopathy with no known cause. It appears to be a genetic condition (passed down through a family’s genes). ARVD causes ventricular arrhythmias.
Arteriography
A test that is combined with cardiac catheterization to visualize an artery or the arterial system after injection of a contrast dye.
Arterioles
Small, muscular branches of arteries. When they contract, they raise resistance to blood flow, and blood pressure in the arteries increases.
Artery
A vessel that carries oxygen-rich blood to the body.
Arteritis
Inflammation of the arteries.
Arteriosclerosis
A disease process, commonly called “hardening of the arteries”, which includes a variety of conditions that cause artery walls to thicken and lose elasticity.
Artificial heart
A manmade heart. Also called a total artificial heart (TAH).
Ascending aorta
The first portion of the aorta, emerging from the heart’s left ventricle.
Aspirin
Acetylsalicylic acid; a medicine used to relieve pain, reduce inflammation, and prevent blood clots.
Atherectomy
A nonsurgical technique for treating diseased arteries with a rotating device that cuts or shaves away material that is blocking or narrowing an artery.
Atherosclerosis
A disease process that leads to the buildup of a waxy substance, called plaque, inside blood vessels
Atrium (right and left)
The two upper or holding chambers of the heart (together referred to as atria).
Atrial flutter
A type of arrhythmia in which the upper chambers of the heart (the atria) beat very fast, causing the walls of the lower chambers (the ventricles) to beat inefficiently as well.
Atrial septal defect
See septal defect.
Atrial tachycardia
A type of arrhythmia that begins in the heart’s upper chambers (the atria) and causes a very fast heart rate of 160 to 200 beats a minute. A resting heart rate is normally 60 to 100 beats a minute.
Atrioventricular block
An interruption or disturbance of the electrical signal between the heart’s upper two chambers (the atria) and lower two chambers (the ventricles).
Atrioventricular (AV) node
A group of cells in the heart located between the upper two chambers (the atria) and the lower two chambers (the ventricles) that regulates the electrical current that passes through it to the ventricles.
Atrium
Either one of the heart’s two upper chambers.
Autologous
Relating to self. For example, autologous stem cells are those taken from the patient’s own body.
Autoregulation
When blood flow to an organ stays the same although pressure in the artery that delivers blood to that organ may have changed.
Bacteria
Germs that can lead to disease.
Bacterial endocarditis
A bacterial infection of the lining of the heart’s chambers (called the endocardium) or of the heart’s valves.
Balloon catheter
A long tube-like device with a small balloon on the end that can be threaded through an artery. Used in angioplasty or valvuloplasty.
Balloon valvuloplasty
A procedure to repair a heart valve. A balloon-tipped catheter is threaded through an artery and into the heart. The balloon is inflated to open and separate any narrowed or stiffened flaps (called leaflets) of a valve.
Beta-blocker
An antihypertensive medicine that limits the activity of epinephrine, a hormone that increases blood pressure.
Biopsy
The process by which a small sample of tissue is taken for examination.
Blalock-Taussig procedure
A shunt between the subclavian and pulmonary arteries used to increase the supply of oxygen-rich blood in “blue babies” .
Blood clot
A jelly-like mass of blood tissue formed by clotting factors in the blood. Clots stop the flow of blood from an injury. Clots can also form inside an artery when the artery’s walls are damaged by atherosclerotic buildup, possibly causing a heart attack or stroke.
Blood pressure
The force or pressure exerted by the heart in pumping blood; the pressure of blood in the arteries.
Blue babies
Babies who have a blue tinge to their skin (cyanosis) resulting from insufficient oxygen in the arterial blood. This condition often indicates a heart defect.
Body mass index (BMI)
A number that indicates an increased risk of cardiovascular disease from a person being overweight. BMI is calculated using a formula of weight in kilograms divided by height in meters squared (BMI =W [kg]/H [m2]). Click here for a BMI calculator.
Bradycardia
Abnormally slow heartbeat.
Bridge to transplant
Use of mechanical circulatory support to keep heart failure patients alive until a donor heart becomes available.
Bruit
A sound made in the blood vessels resulting from turbulence, perhaps because of a buildup of plaque or damage to the vessels.
Bundle branch block
A condition in which parts of the heart’s conduction system are defective and unable to conduct the electrical signal normally, causing an irregular heart rhythm (arrhythmia).
Bypass
Surgery that can improve blood flow to the heart (or other organs and tissues) by providing a new route, or “bypass” around a section of clogged or diseased artery.
Calcium channel blocker (or calcium blocker)
A medicine that lowers blood pressure by regulating calcium-related electrical activity in the heart.
Capillaries
Microscopically small blood vessels between arteries and veins that distribute oxygen-rich blood to the body’s tissues.
Cardiac
Pertaining to the heart.
Cardiac amyloidosis
A disorder caused by deposits of an abnormal protein (amyloid) in the heart tissue, which make it hard for the heart to work properly. Also called “stiff heart syndrome.”
Cardiac arrest
The stopping of the heartbeat, usually because of interference with the electrical signal (often associated with coronary heart disease).
Cardiac cachexia
A term for the muscle and weight loss caused by severe heart disease. It is often related to the depressed cardiac output associated with end-stage heart failure, but it can also occur with severe coronary artery disease.
Cardiac catheterization
A procedure that involves inserting a fine, hollow tube (catheter) into an artery, usually in the groin area, and passing the tube into the heart. Often used along with angiography and other procedures, cardiac catheterization has become a primary tool for visualizing the heart and blood vessels and diagnosing and treating heart disease.
Cardiac enzymes
Complex substances capable of speeding up certain biochemical processes in the heart muscle. Abnormal levels of these enzymes signal heart attack.
Cardiac output
The amount of blood the heart pumps through the circulatory system in one minute.
Cardiologist
A doctor who specializes in the study of the heart and its function in health and disease.
Cardiology
The study of the heart and its function in health and disease.
Cardiomegaly
An enlarged heart. It is usually a sign of an underlying problem, such as high blood pressure, heart valve problems, or cardiomyopathy.
Cardiomyopathy
A disease of the heart muscle that leads to generalized deterioration of the muscle and its pumping ability.
Cardiopulmonary bypass
The process by which a machine is used to do the work of the heart and lungs so the heart can be stopped during surgery.
Cardiopulmonary resuscitation (CPR)
An emergency measure that can maintain a person’s breathing and heartbeat. The person who performs CPR actually helps the patient’s circulatory system by breathing into the patient’s mouth to give them oxygen and by giving chest compressions to circulate the patient’s blood. Hands-only CPR involves only chest compressions.
Cardiovascular (CV)
Pertaining to the heart and blood vessels that make up the circulatory system.
Cardiovascular Disease (CVD)
A general term referring to conditions affecting the heart (cardio) and blood vessels (vascular system). May also simply be called heart disease. Examples include coronary artery disease, valve disease, arrhythmia, peripheral vascular disease, congenital heart defects, hypertension, and cardiomyopathy. Refer to specific conditions for detailed explanations.
Cardioversion
A technique of applying an electrical shock to the chest to convert an abnormal heartbeat to a normal rhythm.
Carotid artery
A major artery (right and left) in the neck supplying blood to the brain.
Cerebral embolism
A blood clot formed in one part of the body and then carried by the bloodstream to the brain, where it blocks an artery.
Cerebral hemorrhage
Bleeding within the brain resulting from a ruptured blood vessel, aneurysm, or head injury.
Cerebral thrombosis
Formation of a blood clot in an artery that supplies part of the brain.
Cerebrovascular
Pertaining to the blood vessels of the brain.
Cerebrovascular accident
Also called cerebral vascular accident, apoplexy, or stroke. Blood supply to some part of the brain is slowed or stopped, resulting in injury to brain tissue.
Cerebrovascular occlusion
The blocking or closing of a blood vessel in the brain.
Cholesterol
An oily substance that occurs naturally in the body, in animal fats and in dairy products, and that is transported in the blood. Limited amounts are essential for the normal development of cell membranes. Excess amounts can lead to coronary artery disease.
Cineangiography
The technique of using moving pictures to show how a special dye passes through blood vessels, allowing doctors to diagnose diseases of the heart and blood vessels.
Circulatory system
Pertaining to circulation of blood through the heart and blood vessels.
Claudication
A tiredness or pain in the arms and legs caused by an inadequate supply of oxygen to the muscles, usually due to narrowed arteries or peripheral arterial disease (PAD).
Collateral circulation
Blood flow through small, nearby vessels in response to blockage of a main blood vessel.
Commissurotomy
A procedure used to widen the opening of a heart valve that has been narrowed by scar tissue.
Computed tomography (CT or CAT scan
An x-ray technique that uses a computer to create cross-sectional images of the body.
Conduction system
Special muscle fibers that conduct electrical impulses throughout the heart muscle.
Congenital
Refers to conditions existing at birth.
Congenital heart defects
Malformation of the heart or of its major blood vessels present at birth.
Congestive heart failure
A condition in which the heart cannot pump all the blood returning to it, leading to a backup of blood in the vessels and an accumulation of fluid in the body’s tissues, including the lungs.
Coronary arteries
Two arteries arising from the aorta that arch down over the top of the heart and divide into branches. They provide blood to the heart muscle.
Coronary artery anomaly (CAA
A congenital defect in one or more of the coronary arteries of the heart.
Coronary artery bypass (CAB)
Surgical rerouting of blood around a diseased vessel that supplies blood to the heart. Done by grafting either a piece of vein from the leg or a piece of the artery from under the breastbone.
Coronary artery disease (CAD)
A narrowing of the arteries that supply blood to the heart. The condition results from a buildup of plaque and greatly increases the risk of a heart attack.
Coronary heart disease
Disease of the heart caused by a buildup of atherosclerotic plaque in the coronary arteries that can lead to angina pectoris or heart attack.
Coronary occlusion
An obstruction of one of the coronary arteries that hinders blood flow to the heart muscle.