When your heart is working properly, the mitral valve closes completely during contraction of the left ventricle and prevents blood from flowing back into your heart's upper left chamber (left atrium).

But in some people with mitral valve prolapse, one or both of the mitral valve's flaps (leaflets) have extra tissue bulging (prolapsing) like a parachute into the left atrium each time the heart contracts.

The bulging may keep the valve from closing tightly. When blood leaks backward through the valve, it's called mitral valve regurgitation.

This may not cause problems if only a small amount of blood leaks back into the atrium. More severe mitral valve regurgitation can cause symptoms such as shortness of breath, fatigue or lightheadedness.

Another name for mitral valve prolapse is click-murmur syndrome. When a doctor listens to your heart using a stethoscope, he or she may hear a clicking sound as the valve's leaflets billow out, followed by a murmur resulting from blood flowing back into the atrium. Other names to describe mitral valve prolapse include:

  • Barlow's syndrome
  • Floppy valve syndrome
  • Balloon mitral valve
  • Billowing mitral valve
  • Myxomatous mitral valve
  • Prolapsing mitral valve syndrome
Apr. 05, 2014