The flow of blood pumped by the heart is controlled by one-way valves. These valves assure that blood moves in only one direction. Mitral regurgitation occurs when the heart's mitral valve leaks blood into the upper chamber from the lower chamber.

If the amount of blood that leaks is severe, mitral regurgitation can be a serious condition that requires care from your doctor. The sooner it is treated, the better the outcome. If you suspect that you have this condition, contact your doctor right away.

Mitral Valve Regurgitation
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There are several causes for leaky heart valves. Birth defects can deform them. Infections can scar them. Heart attacks can damage them. The mechanics of an enlarged heart can stretch out the opening so that the valve is no longer large enough to work effectively.

  • Mitral valve prolapse—abnormal closure of the valve with protrusion of a leaflet tip backward into the left atrium, causing it to leak. This may be congenital or acquired.
  • Rheumatic fever —infectious disease can afflict the inside of the heart, leading to scarring of the heart’s valves. Rheumatic fever used to be a common cause of mitral valve damage, but it is not common today in the United States.
  • Heart attack —reduced blood supply to the heart can weaken the small muscles that hold the mitral valve in place, causing it to leak
  • Congenital deformity—several different types of congenital heart defects distort the mitral valve
  • Heart muscle disease—many types of disease can weaken the heart muscle, stretching out the mitral valve ring so that the valve no longer closes. Among these causes are alcohol, certain drugs, radiation, muscular dystrophies, malnutrition, cancer, and many inflammatory and metabolic disorders.