Mitral Valve Prolapse

Mitral valve prolapse (MVP) occurs when the two leaflets — flap-like doors — of the heart's mitral valve fail to form a tight seal. The mitral valve controls blood flow between the upper and lower chambers of the heart's left side, and a tight seal is key for keeping blood moving in the right direction.

A healthy mitral valve keeps a tight seal by opening and closing quickly and completely. But sometimes factors like age, genetics or anatomical differences cause the mitral valve to loosen or bulge a bit, which doctors call "prolapse." When prolapse occurs, the mitral valve may allow some blood to move back into the lungs.

A mild mitral valve prolapse often doesn't cause any symptoms. Symptoms of a significant prolapse may include:

  • Shortness of breath
  • Bursts of rapid heartbeat (palpitations)
  • Chest discomfort
  • Fatigue

Usually, people have mitral valve prolapse at birth, but it can also develop with age due to normal wear and tear of the heart. Either way, a doctor can detect MVP by listening to the heart with a stethoscope. A prolapsing valve may make a clicking sound as it opens and shuts. It may also make a whooshing sound as blood moves into the lungs. In fact, MVP was once known as "click-murmur syndrome."

If a mitral valve prolapse is suspected, your doctor may order one of the following diagnostic tests:

  • Echocardiogram, with or without a Doppler ultrasound — Uses sound waves to create a moving image of the heart at work
  • Chest X-ray — Looks for fluid in the lungs or an enlarged heart
  • Electrocardiogram (EKG) — Measures the heart's electrical activity to determine how fast it's beating and if the rhythm is steady

In many cases, mitral valve prolapse doesn't cause any symptoms and doesn't require treatment. If mild symptoms or irregularities arise, they can often be controlled with medication, such as a beta blocker, which may ease discomfort. Other moderate symptoms can also be corrected with medication, such as digoxin to strengthen the heartbeat, blood thinners to reduce the risk of clots and vasodilators to relax the blood vessels. However, if the problem worsens, surgery may be the best option.

Most prolapsing valves can be repaired with a minimally invasive procedure called keyhole surgery. A surgeon will make a small incision on the right side of the chest, then thread a long, slim, robotic-assisted endoscope between two ribs to reach the heart. Compared to open heart surgery, this approach results in less pain, less blood loss and a faster recovery time.

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Reviewed by health care specialists at UCSF Medical Center.

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Heart & Vascular Center

Cardiothoracic Surgery
400 Parnassus Ave., Fifth Floor
San Francisco, CA 94143
Phone: (415) 353-1606
Fax: (415) 353-1312
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