What Is a Heart Attack?

A heart attack happens when the flow of oxygen-rich blood to a section of heart muscle suddenly becomes blocked and the heart can’t get oxygen. If blood flow isn’t restored quickly, the section of heart muscle begins to die.

Heart attacks are a leading killer of both men and women in the United States.

What are the heart valves?

There are four valves which control the blood flow through the heart. They all consist of two or three flaps which swing open to allow blood through with each heart beat, and swing closed to prevent blood going back in the wrong direction.

Deoxygenated (blue) blood returning from the body collects in the right atrium.

How does the normal heart work?

Your heart is a specialised muscle that pumps blood around your body. Blood carries oxygen and nourishment to all parts of your body and carries waste products to several organs, notably your lungs and kidneys, for removal.

Your heart is divided into two pumps, which work together. Blood coming back from the organs and tissues of your body enters the right side of your heart,