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      How the Heart Works
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What Is ...
Electrical System
Heart Disease

What Is the Heart?

Your heart is a muscular organ that acts like a pump to send blood throughout your body all the time.

Your heart is at the center of your circulatory system, which delivers blood to all areas of your body. An electrical system regulates the heart and uses electrical signals to contract the heart’s walls. When the walls contract, blood is pumped into your circulatory system.

Your circulatory system is made up of a network of blood vessels, such as arteries, veins, and capillaries. The vessels in this network carry blood to and from all areas of your body. A system of inlet and outlet valves in your heart’s chambers works to ensure that blood flows in the right direction.

Your heart is vital to your health and nearly everything that goes on in your body. Without the heart’s pumping action, blood can’t circulate within your body.

Your blood carries the oxygen and nutrients that your organs need to function normally. Blood also carries carbon dioxide, a waste product, to your lungs to be passed out of your body and into the air. A healthy heart supplies the areas of your body with the right amount of blood at the right rate needed to function normally. If disease or injury weakens your heart, your body’s organs won’t receive enough blood to function normally.

January 2007

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