Mitral valve prolapse (MVP) is a condition in which the heart’s mitral valve doesn’t work well. The flaps of the valve are “floppy” and may not close tightly. These flaps normally help seal or open the valve.
Much of the time, MVP doesn’t cause any problems. Rarely, blood can leak the wrong way through the floppy valve. This can lead to palpitations, shortness of breath, chest pain, and other symptoms. (Palpitations are feelings that your heart is skipping a beat, fluttering, or beating too hard or too fast.)
Normal Mitral Valve
The mitral valve controls blood flow between the upper and lower chambers of the left side of the heart. The upper chamber is called the left atrium. The lower chamber is called the left ventricle.
The mitral valve allows blood to flow from the left atrium into the left ventricle, but not back the other way. The heart also has a right atrium and ventricle, separated by the tricuspid valve.
With each heartbeat, the atria contract and push blood into the ventricles. The flaps of the mitral and tricuspid valves open to let blood through. Then, the ventricles contract to pump the blood out of the heart.
When the ventricles contract, the flaps of the mitral and tricuspid valves close. They form a tight seal that prevents blood from flowing back into the atria.
For more information, go to the Health Topics How the Heart Works article. This article contains animations that show how your heart pumps blood and how your heart’s electrical system works.
Mitral Valve Prolapse
In MVP, when the left ventricle contracts, one or both flaps of the mitral valve flop or bulge back (prolapse) into the left atrium. This can prevent the valve from forming a tight seal. As a result, blood may leak from the ventricle back into the atrium. The backflow of blood is called regurgitation.
MVP doesn’t always cause backflow. In fact, most people who have MVP don’t have backflow and never have any related symptoms or problems. When backflow occurs, it can get worse over time and it can change the heart’s size and raise pressure in the left atrium and lungs. Backflow also raises the risk of heart valve infections.
Medicines can treat troublesome MVP symptoms and help prevent complications. Some people will need surgery to repair or replace their mitral valves.
Mitral Valve Prolapse