The mitral valve controls the flow of blood into the left ventricle. Normally, when the left ventricle contracts the mitral valve closes and the blood flows out through the aortic valve.
In mitral valve prolapse, the shape or dimensions of the leaflets of the valve are not ideal - they may be too large and fail to close properly or balloon out - hence the term "prolapse."
Although, in general, healthy hearts are structurally similar, like other parts of the body, there are individual variations. The heart's valves work to maintain the flow of blood in one direction, ensuring proper circulation. When the valve leaflets flap, a clicking sound may be heard. Sometimes the prolapsing of the mitral valve allows a slight flow of blood back into the left atrium, which is called "mitral regurgitation," and this may cause a sound called a murmur.
Mitral valve prolapse is often called the "clickmurmur syndrome" because these sounds are often heard. Some people with mitral valve prolapse have both a click and a murmur, and some have only a click. Many have no unusual heart sounds at all; those who do, may have clicks and murmurs which come and go.
Mitral valve prolapse is one of the most frequently made cardiac diagnoses in the U.S. and is more common in women than in men. It also occurs more often in women who have scoliosis or other skeletal abnormalities.
It appears to be congenital and present at birth but is not usually detected until later.
Most people with mitral valve prolapse do not have symptoms. Some people may have brief episodes of rapid heartbeat (palpitation) or chest pain that is not typical of angina. A few may experience fatigue, shortness of breath, light-headedness, or loss of consciousness. An extremely rare occurrence is sudden death.
About 15 percent of people with mitral valve prolapse may experience symptoms of valve leakage that are significant enough to require careful evaluation of the mitral valve and consideration of valve surgery.
Mitral valve prolapse may place one at risk for infective endocarditis (inflammation of the lining of the heart). Although the risk is small, endocarditis is such a serious complication that most doctors will recommend that preventive antibiotics be taken before and after dental and some surgical procedures.
Many people with mitral valve prolapse suffer from undue anxiety. Perhaps this anxiety is in some ways explainable. Many people visit doctors with otherwise inexplicable aches or pains or strange sensations. By default, in those who have mitral valve prolapse, the condition becomes a scapegoat. Naturally, the patient becomes concerned. However, the mitral valve prolapse actually is not the source of the problem.
Most often, treatment for mitral valve prolapse is not necessary. If symptoms develop and interfere with the enjoyment of life, beta-blocking drugs may be helpful in relieving palpitations or chest discomfort. Individuals with signs of severe mitral valve prolapse are at greater risk for both infective endocarditis and problems associated with mitral regurgitation, including heart failure.