Mitral Valve Disease

The mitral valve lies between the heart's left atrium and the left ventricle. It has two flaps (leaflets) that open and close like a pair of swinging doors. When the heart beats, the left ventricle pumps blood out to the body and the leaflets swing shut. This keeps the blood in the ventricle from going back into the left atrium. If the mitral leaflets are too floppy, big, thin, or have the wrong shape, they may not shut properly. This condition, called mitral valve prolapse (MVP), allows blood to leak back (regurgitate) into the left atrium.

Usually, MVP is a genetic (inherited) condition that does not cause health problems. Most patients with MVP require no invasive treatment. However, rare but serious complications may occur, which include severe mitral regurgitation, infectious endocarditis (inflammation of the heart's inner lining), heart attack, stroke, or sudden cardiac death. Echocardiography, which is used to diagnose MVP, may also identify patients at high risk for complications. When necessary, treatment generally involves surgery to physically correct mitral valve defects.

Often caused by a history of rheumatic fever, this condition is characterized by a narrowing of the mitral valve opening, increasing resistance to blood flow from the left atrium to the left ventricle.