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Last Edited: 9/30/2010

Heart Attack: What is it?

A heart attack occurs when blood flow that brings oxygen to the heart muscle is severely reduced or cut off completely. This happens when the vessels supplying blood to the heart muscle are damaged, most commonly due to Cardiovascular Disease (CVD).   Heart attacks can be prevented by controlling factors that contribute to CVD.

What causes heart attacks?

Most heart attacks occur as a result of buildup overtime of plaque on the inner walls of the coronary arteries, which are the vessels that supply blood to the heart. Eventually, this buildup can result in the formation of a blood clot. If the clot becomes large enough to cut off most or all the blood flow through the artery, then a heart attack will occur. If the blockage isn’t treated quickly, the damaged heart muscle begins to die.

Another cause of heart attacks is a problem with the very small, microscopic blood vessels of the heart.  This is more common in women than in men.  Heart attacks may occur when a coronary artery undergoes a spasm, which further cuts off blood flow to the heart of a person with CVD.  It’s not clear what causes these spasms, but sometimes they can be related to taking certain drugs, emotional stress or pain, exposure to extreme cold, and cigarette smoking.


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What are risk factors for a heart attack?

There are many modifiable risk factors that are associated with CVD and heart attacks:

  • Tobacco smoke
  • Stress
  • High blood pressure
  • High blood cholesterol
  • Physical inactivity
  • Obesity
  • Alcohol
  • Diabetes

There are also other factors that can’t be controlled:

  • Age: Risk increases for men older than 45 and for women older than 55 years.
  • Family history of early heart disease: Risk increases if your immediate family was diagnosed with CVD at an early age (younger than age 55 for men and  younger than age 65 for women).

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What are the symptoms of a heart attack?

Not everyone who experiences a heart attack has the same signs and symptoms. Here are the more common ones:

  • Chest pain or discomfort in the center of the chest that lasts for more than a few minutes, or goes away and comes back
  • Upper body discomfort in one or both arms, the back, neck, jaw, and stomach
  • Shortness of breath with or before chest discomfort
  • Nausea, vomiting, lightheadedness or fainting, or breaking out in a cold sweat

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How are heart attacks diagnosed?

The diagnosis of a heart attack is based on the person’s symptoms, personal and family medical history, and the results of diagnostic tests.

Diagnostic tests include:

  • The EKG (Electrocardiogram): this test detects and records the electrical activity of the heart. Certain changes in the electrical waves being monitored by the EKG may indicate a heart attack.
  • Blood tests: this test measures the amount of certain proteins in the bloodstream which would be higher than normal levels if experiencing a heart attack.
  • Coronary Angiography: a special x-ray exam of the heart and blood vessels.

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