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Science

Heart disease

The heart

The heart is a muscular organ. It keeps beating at about 70 times per minute. You can see how it pumps the blood to the lungs and the rest of the body by studying this animation.

The muscle cells in the heart need a constant supply of oxygen and nutrients, and for their waste products to be removed. So the heart requires its own blood supply in order to keep beating.

Blood vessels called the coronary arteries supply blood to the heart muscles. If they become blocked, a heart attack can happen.

Heart attacks

A heart attack can happen because:

  1. Fatty deposits build up in the coronary arteries
  2. A blood clot can form on a fatty deposit
  3. The blood clot can block a coronary artery
  4. Some heart muscle cells do not get the oxygen and nutrients they need
  5. These cells start to die.

In the UK about 300,000 people have a heart attack every year.

Back to Keeping healthy index

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