Your Heart: 101

Heart anatomy

At the right is a diagram of a healthy heart and its major structures (click on image to view larger). The heart has four chambers and four valves that control blood flow.

Your heart muscle pumps blood to all the tissues in your body through your blood vessels. The right side of the heart pumps blood through the lungs. The blood picks up oxygen in the lungs. Then, the left side of the heart receives the (now oxygen-rich) blood and pumps it to the rest of your body.

Your heart beats day after day, year after year. In fact, it beats about 80 million times a year, or 5 to 6 billion beats in an average lifetime. Each beat is the result of the blood flowing through the heart in the right direction and with the right force. Heart valves take care of that.

The chart below lists each one and tells you what it does.

What It IsWhat It Does
Left and right atria Chambers that receive blood returning from your body through your veins
Left and right ventricles Chambers where blood is pumped to your body through your arteries
Mitral valve Controls the flow of oxygen-rich blood from the left atrium to the left ventricle
Tricuspid valve Controls the flow of oxygen-poor blood from the right atrium to the right ventricle
Aortic valve Controls flow of oxygen-rich blood from the left ventricle to the body
Pulmonary valve Controls flow of oxygen-poor blood from the right ventricle to the lungs