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Heart Attack

Heart attacks are often thought of as a sudden, pressure-like chest pain that takes a person by complete surprise. But heart attacks can have early warning signs, and often result from heart disease that builds up over time. A key to preventing a heart attack is knowing the risk factors that can lead to heart disease. A key to surviving a heart attack is knowing its early warning signs.

What causes heart attacks?

The main cause of a heart attack is a sudden blockage of a coronary artery from a blood clot that forms on the plaque.

What happens during a heart attack?

Coronary Arteries

A network of blood vessels known as coronary arteries surround the heart muscle and supply it with blood that is rich in oxygen. The heart muscle needs this oxygen to function.

A heart attack occurs when a coronary artery becomes suddenly blocked, stopping the flow of blood to the heart muscle and damaging it. All or part of the heart muscle becomes cut off from its oxygen supply. Left without oxygen, the heart muscle is injured.

What is coronary artery disease?

Coronary artery disease (also known as atherosclerosis, or hardening of the arteries) occurs when fatty deposits build up within the artery walls. Over time, the fatty deposits harden, narrowing the passageway inside the blood vessel. The narrowed artery limits or pinches off the flow of blood to the heart muscle.

The rough, hardened surface of the artery also encourages small blood clots to form. Most heart attacks result when a blood clot forms in a narrowed artery. The blood clot blocks the artery and prevents blood from reaching part of the heart muscle.

This information is provided by Cleveland Clinic and is not intended to replace the medical advice of your doctor or health care provider. Please consult your health care provider for advice about a specific medical condition. This document was last reviewed on: 7/10/2011...#4235

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