Acute mitral regurgitation is a condition that affects the mitral valve in the heart. The mitral valve does not close completely, causing the blood to flow in the wrong direction. The mitral valve separates the heart's left atrium, or upper chamber, from the left ventricle, or lower chamber.
The left atrium receives blood from the lungs and passes it through the mitral valve to the left ventricle. The left ventricle pumps blood to the rest of the body. The mitral valve normally remains firm when the left ventricle contracts.
In a person who has acute mitral regurgitation, the mitral valve no longer closes properly. With every heartbeat, some blood is pumped back through the valve and into the upper part of the heart. The body is not able to pump enough blood to the rest of the body.
Mitral regurgitation is caused when the mitral valve fails to close properly. Some people are born with a defective mitral valve. Diseases and conditions that can cause mitral regurgitation include the following: