Mitral valve prolapse (MVP) is a common condition that affects one of the heart's valves. It occurs in about 1 out of every 50 people and is seen twice as often in women as in men. This condition can be undetected for years and doesn't usually cause serious heart problems. Most people with MVP require no treatment.
The mitral valve is the heart valve located between the upper and lower chambers of the left side of the heart. The mitral valve is made up of two flaps and controls the blood flow from the top chamber of the left side of the heart (the left atrium) to its bottom chamber (the left ventricle).
But in MVP, one or both of the flaps are too big. The valve can't close properly and will bulge out or prolapse into the left atrium. With a stethoscope, doctors may hear the soft "clicking" sound of the bulging. Sometimes, the bulging creates a little space between the flaps, which lets the blood leak backwards into the left atrium from the ventricle. This leak can cause a "whooshing" sound that can also be heard with the stethoscope.
MVP is sometimes inherited. Some people with MVP have minor deformities of the chest, back, and spine. In rare cases, inherited diseases such as Marfan's syndrome have been associated with MVP.