Acting like a pump, the human heart is a muscle that contracts and relaxes each time it beats. Ther...
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Acting like a pump, the human heart is a muscle that contracts and relaxes each time it beats. There are four heart compartments or chambers. The upper two are the atria, and the lower two are ventricles. Blood comes into the chambers and is then pumped to the rest of the body to supply nourishment. The flow of blood inside the heart is controlled by four thin, flexible valves that open and close with each heartbeat. They are the tricuspid valve, the pulmonic valve, the mitral valve, and the aortic valve. The aortic valve is composed of 3 tissue flaps, called leaflets. It is located between the left ventricle and the aorta, the blood vessel that carries blood to the rest of the body. The aortic valve opens to move blood from the heart into the aorta. Aortic valve stenosis means the valve opening in the heart is narrow so the valve does not open all the way. As a result, the heart must work harder to pump blood to the body.