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Heart Health Glossary



Angina (an-JI-nuh or AN-juh-nuh) is chest pain or discomfort that occurs if an area of your heart muscle doesn't get enough oxygen-rich blood. It may feel like pressure or squeezing in your chest. The pain also can occur in your shoulders, arms, neck, jaw, or back. Angina pain may even feel like indigestion.


An arrhythmia (ah-RITH-me-ah) is a problem with the rate or rhythm of the heartbeat. During an arrhythmia, the heart can beat too fast, too slow, or with an irregular rhythm.Anatomy of the heart showing atria, ventricles, and blood vessels


Arteriosclerosis (ahr-teer-ee-o-skluh-roh-sis) is when the large arteries become stiffer and less elastic as you get older. These changes are caused by deposits of collagen and scar tissue as well as a decrease in the molecules that make the arterial wall flexible and elastic. These changes result in high blood pressure, which increases the risk of coronary heart disease, heart attacks, heart failure, stroke, and disease of the kidneys, brain, and eyes.


Atherosclerosis (ath-uh-roh-skluh-roh-sis), which is a type of arteriosclerosis, describes the buildup of plaque within the arterial wall. Arteries are blood vessels that carry oxygen-rich blood to your heart and other parts of your body. While aging changes, such as arteriosclerosis (or increased arterial stiffness), increase the risk of atherosclerosis, aging changes do not directly cause atherosclerosis.

Cardiovascular disease

Cardiovascular disease is the term for all types of diseases that affect the heart or blood vessels, including coronary heart disease (plaque accumulation in arteries), which can cause heart attacks, stroke, heart failure, and peripheral artery disease.

Coronary heart disease

Coronary heart disease (CHD) (also known as coronary artery disease or heart disease) is a disease in which a waxy substance called plaque builds up inside the coronary arteries. These arteries supply oxygen-rich blood to your heart muscle.


An electrocardiogram, also called an ECG or EKG, is a simple, painless test that detects and records your heart's electrical activity. This test helps to diagnose a heart attack or arrhythmia.

Heart attack

A heart attack (also known as myocardial infarction) happens when the flow of oxygen-rich blood to a section of heart muscle suddenly becomes blocked and the heart muscle can't get enough oxygen. If blood flow isn't restored quickly, the section of heart muscle begins to die.

Heart failure

Heart failure (also known as congestive heart failure) is a condition in which the heart can't pump enough blood to meet the body's needs. In some cases, the heart can't fill with enough blood. In other cases, the heart can't pump blood to the rest of the body with enough force. Some people have both problems.

High blood pressure

High blood pressure (also known as hypertension) is a common disease in which blood flows through blood vessels (arteries) at higher-than-normal pressures.


A stroke occurs if the flow of oxygen-rich blood to a portion of the brain is blocked. Without oxygen, brain cells start to die after a few minutes. Sudden bleeding in the brain also can cause a stroke if it damages brain cells.

Sudden cardiac arrest

Sudden cardiac arrest (SCA) (also known as cardiac arrest or sudden cardiac death) is a condition in which the heart suddenly and unexpectedly stops beating. If this happens, blood stops flowing to the brain and other vital organs. Cardiopulmonary resuscitation (CPR) should be started immediately if SCA is witnessed. The heart rhythm can be restored by an automated external defibrillator (AED).

This content is provided by the NIH National Institute on Aging (NIA). NIA scientists and other experts review this content to ensure it is accurate and up to date.

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