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Glossary A-H


Glossary Credits: WebMD and the Cleveland Clinic Heart Center.

+ Ablation

The removal or destruction of tissue.

+ Advance Directive (living will)

A document written in “good” health which informs your family and health care providers of your wishes for extended medical treatment in times of emergency.

+ Aerobic Exercise

Exercise which can improve your functional ability and, in some cases, reduce symptoms of heart disease. It is repetitive in nature and involves the large muscle groups. Examples are walking, swimming, and cycling.

+ Ambulatory Monitors

Small portable electrocardiograph machines that are able to record the heart’s rhythm. Each type of monitor has unique features related to length of recording time and ability to send the recordings over the phone. They include: Holter Monitor, Loop Recorder, and Transtelephonic transmitter.

+ Anemia

A condition characterized by a deficiency of red blood cells. Anemia reduces the amount of oxygen available to the body.

+ Aneurysm

A sac formed by the bulging of a blood vessel wall or heart tissue. When aneurysms grow too large, they can rupture and the bleeding can be life threatening. Aneurysms that have grown too large should be removed.

+ Angina (also called angina pectoris)

Discomfort or pressure, usually in the chest, caused by a temporarily inadequate blood supply to the heart muscle. Discomfort may also be felt in the neck, jaw or arms.

+ Angiogenesis

The spontaneous or drug-induced growth of new blood vessels. The growth of these vessels may help to alleviate coronary artery disease by rerouting blood flow around clogged arteries.

+ Angioplasty

An invasive procedure, during which a specially designed balloon catheter with a small balloon tip is guided to the point of narrowing in the artery. Once in place, the balloon is inflated to compress the fatty matter into the artery wall and stretch the artery open to increase blood flow to the heart.

+ Angiotensin-Converting Enzyme Inhibitors (ACE inhibitors)

A group of drugs used to treat high blood pressure and heart failure. ACE inhibitors block a specific enzyme (ACE or angiotensin-converting enzyme) that retains salt in the kidney and can cause heart and blood pressure problems. ACE inhibitors have been shown to decrease the risk of dying from a heart attack.

+ Angiotensin II Receptor Blockers (ARBs)

A group of drugs used to treat high blood pressure.

+ Annulus

A ring of tough fibrous tissue that is attached to and supports the leaflets of the heart valve.

+ Anomalous Coronary Artery

The normal anatomy for the coronary arteries involves their origin from the aorta at each of two separate sites. Sometimes people can be born with the origin of a coronary artery that comes from an abnormal site and this can lead to problems of coronary ischemia which can subsequently lead to a heart attack. Not all coronary anomalies need surgery, but some do and the specific operation depends on which of the many varieties of coronary anomalies is present.

+ Antiarrhythmic

A drug that is used to treat abnormal heart rhythms.

+ Anticoagulant (“blood thinner”)

A medication that prevents blood from clotting; used for people at risk for stroke or blood clots.

+ Antihypertensive

A medication used to treat high blood pressure.

+ Antioxidant

Vitamins (A, C and E) that may help to limit the cellular damage caused by free radicals (which are released when tissue is being injured, such as during the progression of heart disease.) Studies suggest that certain antioxidants may protect against coronary artery disease.

+ Aorta

Large artery leaving the heart. All blood pumped out of the left ventricle travels through the aorta on its way to other parts of the body.

+ Aortic Insufficiency

Aortic insufficiency refers specifically to the aortic valve, which is the valve the blood passes through as it leaves the heart and enters the aorta. When blood leaks back through the valve it is known as aortic insufficiency. Small amounts of aortic insufficiency may be inconsequential, but larger amounts require repair or replacement of the aortic valve.

+ Aortic Valve

The aortic valve is the last valve through which the blood passes before it enters the aorta or main blood vessel of the body. The valve’s role is to prevent blood from leaking back into the left ventricle from the aorta after it has been ejected from the heart.

+ Aortic Valve Replacement

When the aortic valve is diseased, it can become either stenotic (too narrow) or insufficient (leaky). In such cases, the aortic valve may need to be replaced with either a prosthetic or human valve.

+ Aortic Valve Homograft

When replacement of an aortic valve is necessary it is possible to replace the valve with another human valve known as an aortic valve homograft. This operation involves cardiopulmonary bypass.

+ Aortic Valve Repair

The aortic valve is the last valve in the heart through which the blood travels prior to circulating in the body. When this valve is leaking or too tight, a surgeon may be able to repair the valve rather than replace it.

+ Arrhythmia

An irregular heartbeat.

+ Arterial Grafting

In patients who require coronary artery bypass graft surgery, it is sometimes desirable to use arteries from other parts of the body to provide the bypass grafts. This is known as arterial grafting. The alternative is to use vein grafts for coronary bypass surgery.

+ Arteries

Blood vessels that carry blood away from the heart.

+ Atherectomy (Directional Coronary Atherectomy or DCA)

This procedure is used to clean out clogged heart arteries. A DCA catheter has a hollow cylinder on the tip with an open window on one side and a balloon on the other. When the catheter is inserted into the narrowed artery, the balloon is inflated, pushing the window against the fatty matter clogging the vessel. A blade (cutter) within the cylinder rotates and shaves off any fat, which protruded into the window. The shavings are caught in a chamber within the catheter and removed. This process is repeated as needed to allow better blood flow.

+ Atherosclerosis (“hardening of the arteries”)

The process whereby abnormal deposits of lipids, cholesterol and plaque build up, leading to coronary artery disease and other cardiovascular problems.

+ Atria

The upper chambers of the heart. (Atrium refers to one chamber of the heart).

+ Atrial Fibrillation (AF)

Atrial fibrillation is an irregular heart rhythm in which many impulses begin and spread through the atria. The resulting rhythm is disorganized, rapid and irregular and the atria are not able to fully empty their contents into the ventricles.

+ Atrial Flutter

Atrial flutter is a regular heart rhythm in which many impulses begin and spread through the atria. The resulting rhythm is organized, but so rapid that the atria are not able to fully empty their contents into the ventricles.

+ Atrial Myxoma

A myxoma is a tumor of the heart. It resides in the atrial chamber and causes symptoms when its growth produces a tumor so large it obstructs blood flow through the heart chambers.

+ Atrial Septal Defect

An abnormal hole located in the walls between the two atria. Tiny defects called patent foramen ovale are present in up to 30% of people and are of no consequence except in unusual circumstances. Moderate size to larger size defects should be corrected and may require heart surgery.

+ Atrioventricular (AV) Node

A group of special cells located near the center of the heart that helps to regulate the heart rhythm. Here, the electrical current slows for a moment before going on to the ventricles.

+ Atrium

The top chamber of the heart. There are two atria — the left and the right, divided by a muscular wall, called the septum. The atrium contracts before the ventricle to allow optimal filling of the ventricle.

+ Balloon Angioplasty (Percutaneous Transluminal Coronary Angioplasty or PTCA)

A procedure used to clean out clogged heart arteries. A specially designed balloon catheter with a small balloon tip is guided to the point of narrowing in the artery. Once in place, the balloon is inflated to compress the fatty matter into the artery wall and stretch the artery open to increase blood flow to the heart.

+ Batista Procedure

During this surgical procedure, to treat heart failure, the surgeon cuts out a piece of the patient’s enlarged left ventricular muscle. The intention is to reduce the size of the left ventricular cavity, improve left ventricular function and reverse congestive heart failure. Long-term results found the procedure unsuccessful, however, the procedure has led to better surgical techniques to treat those with heart failure (see infarct exclusion surgery).

+ Beta-Blocker

A drug that slows heart rate, lowers blood pressure, controls angina and protects patients with prior heart attacks from future heart attacks.

+ Bicuspid Valve

A valve with two leaflets (cusps) instead of three.

+ Biopsy

Removal and analysis of a tissue sample.

+ Blood Pressure

The force exerted in the arteries by blood as it circulates. It is divided into systolic (when the heart contracts) and diastolic (when the heart is filling) pressures.

+ Body Mass Index (BMI)

A number that reflects body weight adjusted for height.

+ Bradycardia

A slow heart rate.

+ Bundle Branch

Part of the electrical pathway of the heart that delivers electrical impulses to the ventricles of the heart. Normally, electrical impulses start in the sinoatrial or SA node and travel to the atrioventricular or AV node. Then it goes to the bundle of His. The bundle divides or branches into a right bundle and the left bundle. The bundles take the impulse through the ventricles (bottom chambers) to cause them to contract.

+ Bundle Branch Block

Normally, the electrical impulse travels down both the right and left bundle branches at the same speed and the ventricles contract at the same time. If there is a block in one of the branches, it’s called a bundle branch block. A bundle branch block causes one ventricle to contract just after the other ventricle.

+ Calcium-Channel Blocker

A drug that reduces spasm of the blood vessels, lowers blood pressure, and controls angina; acts by selectively blocking the uptake of calcium by the cells.

+ Capillaries

Tiny blood vessels connecting arteries to veins. These blood vessels carry oxygen and nutrients to individual cells throughout the body.

+ Carbohydrate

An organic compound, found in food substances such as sugar, cereal and other grain products, fruits and vegetables, that provides fuel for the body.

+ Carbon Dioxide

A gas created during metabolism, when the cells use oxygen to burn fat and release energy. The lungs release carbon dioxide when you breathe out.

+ Cardiac Arrest

When the heart stops beating suddenly and respiration (breathing) and other body functions stop as a result.

+ Cardiac Catheterization

A heart procedure used to diagnose heart disease. During the procedure, a catheter (inserted into an artery in your arm or leg) is guided to your heart, contrast dye is injected, and X-rays of the coronary arteries, heart chambers, and valves are taken.

+ Cardiac Output

The amount of blood pumped by the heart each minute.

+ Cardiac Rehabilitation

A structured program of education and activity guided toward lifestyle modification, increasing functional capabilities and peer support.

+ Cardiologist

Doctor specializing in the diagnosis and treatment of heart disease.

+ Cardiomyopathy

An abnormal heart condition in which the heart is dilated (poor pumping power), restrictive (impaired ability of the heart to fill) and hypertrophic (enlarged heart).

+ Cardiopulmonary Recusitation (CPR)

A technique designed to temporarily circulate oxygenated blood through the body of a person whose heart has stopped. It involves assessing the airway; if necessary breathing for the person; determining if the person is without a pulse; and if necessary, applying pressure to the chest to circulate blood.

+ Cardiovascular

Relates to the heart and blood vessels.

+ Cardioversion

A procedure used to convert an irregular heart rhythm to a normal heart rhythm by applying electric shockor using certain medications.

+ Catheter

A slender, hollow, flexible tube.

+ Chest X-ray (CXR, chest film)

A very small amount of radiation is used to produce an image of the structures of the chest (heart, lungs and bones) on film.

+ Cholesterol

A fatty substance made by the body and found in some foods. Cholesterol is deposited in the arteries in coronary artery disease.

+ Chordae Tendinae

Thin chords that provide support to the tricuspid and mitral valves of the heart helping them to open and shut properly.

+ Clubbing

An abnormality where the ends of the fingers and toes enlarge and the nails curve; often it is related to an inadequate oxygen-rich blood supply, however it can be hereditary and completely normal. Often seen with congenital heart defects, but also seen in other conditions.

+ Coarctation of the Aorta

A severe narrowing of the aorta, causing a decrease in blood flow to the lower part of the body. This narrowing is a congenital defect and can be corrected with surgery.

+ Collateral Blood Vessels

Small capillary-like branches of an artery that form over time in response to narrowed coronary arteries. The collaterals “bypass” the area of narrowing and help to restore blood flow. However, during times of increased exertion, the collaterals may not be able to supply enough oxygen-rich blood to the heart muscle.

+ Commissurotomy

A surgical procedure that helps to repair the damage caused by defective heart valves. In some patients, specifically those with rheumatic heart disease, this area of the heart (also called the commissures) can become scarred and the valve leaflets fail to open and allow blood to flow through easily. In this surgery, the commissures can be released or reopened.

+ Complex Carbohydrates

Starchy foods that are good sources of energy and nutrients, such as whole grain breads, rice, and pasta.

+ Congenital Heart Defects

Heart defects present at birth.

+ Congestive Heart Failure (CHF or heart failure)

A condition where the heart muscle weakens and can’t pump blood efficiently throughout the body.

+ Constrictive Pericarditis

The pericardium is the sac around the heart. In people with constrictive pericarditis, this sac becomes inflamed and scarred leading to shrinkage of the pericardium. This can prevent the heart from filling to its full extent.

+ Coronary Arteries

Network of blood vessels that branch off the aorta to supply the heart muscle with oxygen-rich blood. There are two main coronary arteries: the right and the left. The left splits into two arteries called the circumflex and the left anterior descending (LAD) arteries, thus, the heart is often considered to have three major coronary arteries.

+ Coronary Artery Disease (atherosclerosis)

A build-up of fatty material in the wall of the coronary artery that causes narrowing of the artery.

+ Coronary Spasm

Repeated contractions and dilations of the coronary arteries, causing a lack of blood supply to the heart muscle. It may occur at rest and can even occur in people without significant coronary artery disease.

+ Cyanosis

A blue tint to the skin, indicating the body is not receiving enough oxygen-rich blood.

+ Defibrillator

A machine that is used to administer an electric shock to the heart in order to re-establish normal heart rhythm.

+ Diabetes

A condition in which the body does not produce or respond to insulin (a hormone produced by your body, which allows blood sugar or glucose into your body’s cells for energy).

+ Diastolic Pressure

The pressure of the blood in the arteries when the heart is filling. It is the lower of two blood pressure measurements (for example, 120/80, where 80 is the diastolic pressure).

+ Dilated Cardiomyopathy

A disease of the myocardium (heart muscle) that causes the heart cavity to become stretched and enlarged, and the pumping capacity of the heart is reduced.

+ Dilatation

The increase in size of a blood vessel.

+ Dipyridamole Stress Test

If you are unable to exercise on a treadmill or stationary bicycle for a stress test, a medication, called dipyridamole (Persantine) is used instead of exercise to test the heart’s blood flow.

+ Diuretic

A drug that enables the kidneys to rid the body of excess fluid. May be referred to as a “water pill.”.

+ Dobutamine Stress Echocardiogram (Dobutamine echo)

A procedure that involves infusing a medication (dobutamine) through an intravenous (IV) line while you are closely monitored. This drug stimulates your heart allowing evaluation of heart and valve function at rest and with exertion, when you are unable to exercise on a treadmill or stationary cycle.

Echocardiography is an imaging procedure that creates a graphic outline of the heart’s movement, valves and chambers using high-frequency sound waves that come from a hand held wand placed on your chest.

+ Dyspnea

Difficulty breathing.

+ Echocardiogram (echo)

An imaging procedure that creates a moving picture outline of the heart’s valves and chambers using high-frequency sound waves that come from a hand held wand placed on your chest or passed down your throat. Echo is often combined with Doppler ultrasound and color Doppler to evaluate blood flow across the heart’s valves. Doppler senses the speed of sound and can pick up abnormal leakage or blockage of valves.

+ ECMO (Extra corporeal Membrane Oxygenation)

In people who are unable to provide oxygen for their own blood or enough blood circulation, they can be put on life support known as extra corporeal membrane oxygenation. The blood is withdrawn from a large vein in the body and passes through a pumping mechanism, and then through a device that puts oxygen into the blood and removes carbon dioxide from the blood. The blood is then returned to the body and circulated in such a way as to sustain life.

+ Edema

Swelling; the accumulation of fluids, usually in the hands, feet, or abdomen.

+ Ejection Fraction (EF)

The amount of blood pumped out of a ventricle during each heartbeat. The ejection fraction evaluates how well the heart is pumping.

+ Electrocardiogram (ECG, EKG)

The EKG records on graph paper the electrical activity of the heart using small electrode patches attached to the skin.

+ Electrophysiology (EP) Study

An EP study is a test that evaluates the electrical activity within your heart. This test is used to help your doctor find out the cause of your rhythm disturbance and the best treatment for you. During the test, your doctor may safely reproduce your abnormal heart rhythm, then give you medications to see which one controls it best.

+ Embolus

A blood clot that moves through the blood stream.

+ Endocarditis

An infection of the inner lining of the heart or its valves. It is usually caused by bacteria and is more likely to occur in people who have heart valve defects or have had heart surgery to treat valve disease.

+ Enhanced External Counterpulsation (EECP)

A treatment for those with symptomatic coronary artery disease (also called refractory angina), not eligible for standard treatments of revascularization (such as bypass surgery.) During EECP, cuffs wrapped around the calves, thighs and buttocks are inflated and deflated, gently but firmly compressing the blood vessels in the lower limbs, increasing blood flow to the heart. EECP may stimulate the openings or formation of collateral vessels to create a “natural bypass” around narrowed or blocked arteries.

+ Event Monitor (Loop recorder)

A small recorder (monitor) is attached to electrodes on your chest. It is worn continuously for a period of time. If symptoms are felt, an event button can be depressed, and the heart’s rhythm is recorded and saved in the recorder. The rhythm can be saved and transmitted over the phone line.

+ Exercise Stress Echocardiogram (Stress Echo)

A procedure that combines echocardiography with exercise to evaluate the heart’s function at rest and with exertion. Echocardiography is an imaging procedure that creates a picture of the heart’s movement, valves and chambers using high-frequency sound waves that come from a hand held wand placed on your chest. Echo is often combined with Doppler ultrasound and color Doppler to evaluate blood flow across the heart’s valves.

+ Exercise Stress Test

A test used to provide information about how the heart responds to stress. It usually involves walking on a treadmill or pedaling a stationary bike at increasing levels of difficulty, while the electrocardiogram, heart rate and blood pressure are monitored. If you are not able to do activity, medications may be used to “stress” the heart.

+ Fat

A high-energy fuel source.

+ Fiber

An indigestible carbohydrate found in foods such as fruits and vegetables; aids in digestion.

+ Fibrillation

Abnormally rapid, inefficient contractions of the atria or ventricles. Ventricular fibrillation is life-threatening.

+ Flutter

One form of rapid heartbeat.

+ Free Mammary Artery Graft

When the surgeon removes the mammary artery from its origin to use as a bypass graft.

+ Free Radical

A destructive fragment of oxygen produced as a by-product. Increased free radicals are thought to trigger atherosclerosis.

+ Glucose

Blood sugar.

+ Head Upright Tilt Test (HUT, tilt table test, head-up tilt test)

A test used to determine the cause of fainting spells. The test involves being tilted at different angles for a period of time. Heart rhythm, blood pressure, and other measurements are evaluated with changes in position.

+ Heart Attack (myocardial infarction)

Permanent damage to the heart muscle caused by a lack of blood supply to the heart for an extended time period. The severity of damage varies from normal, mild, to severe.

+ Heart Block

An arrhythmia. The electrical current is slowed between the atria and ventricles. In more severe cases, conduction is blocked completely and the atria and ventricles beat independently.

+ Heart Failure (congestive heart failure, CHF)

A condition where the heart muscle weakens and cannot pump blood efficiently. Fluid accumulates in the lungs, hands, ankles, or other parts of the body.

+ Heart Lung Bypass Machine

A machine that oxygenates the blood and circulates it throughout the body during surgery.

+ Heart Surgery

Heart surgery is any surgery that involves the heart or heart valves.

+ Heart Valves

There are four valves in the heart: the tricuspid and the mitral valve, which lie between the atria and ventricles, and the pulmonic and aortic valves, which lie between the ventricles and the blood vessels leaving the heart. The heart valves help to maintain one-way blood flow through the heart.

+ Hemoglobin

A protein in red blood cells that transports oxygen and carbon dioxide and gives blood its red color.

+ Hibernating Myocardium

After a heart attack, some areas of heart muscle do not pump as they should. Some areas will have permanent damage. Other areas are able to return to their normal function if blood flow is returned to that area by medications or a procedure. Hibernating myocardium is heart muscle that is “resting” and may possibly return to normal function.

+ High-Density Lipoprotein (HDL)

Lipoprotein particle in the blood. HDL is known as “good” cholesterol because it deposits cholesterol in the liver, where it is excreted by the body. High HDL is thought to protect against coronary artery disease.

+ Holter Monitor

A small recorder (monitor) is attached to electrodes on your chest. It records the heart’s rhythm continuously for 24-hours. After the monitor is removed the heart’s beats are counted and analyzed by a technician with the aid of a computer. Your doctor can learn if you are having irregular heartbeats, what kind they are, how long they last, as well as what may cause them.

+ Homocysteine

An amino acid. High levels of homocysteine are a risk factor for coronary artery disease.

+ Hydrogenation

A process used to harden unsaturated liquid vegetable oils into saturated fats.

+ Hyperlipidemia

High levels of fat in the blood, such as cholesterol and triglycerides.

+ Hypertension

High blood pressure.

+ Hypertrophic Obstructive Cardiomyopathy (HOCM)

See IHSS below.

+ Hypertrophy

An abnormal enlargement of an organ or thickening of its tissue. Ventricular hypertrophy is the name given to a thickened ventricle.

+ Hypotension

Low blood pressure.

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Reviewed by the doctors at The Cleveland Clinic Heart Center.
Glossary Credits: WebMD

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