The mitral valve controls the flow of blood from the heart’s left atrium down to the left ventricle, where it is pumped out to the body. When part of the valve doesn’t close properly, it’s called mitral valve prolapse (MVP).

One way MVP is often detected is hearing a murmur or clicking sound that the valve makes through a stethoscope.

MVP is a relatively common condition that can be mild and require no treatment, or serious and potentially life threatening. Learn more about this condition, including symptoms, tests, and treatments.

The mitral valve has two leaflets, or flaps. These flaps open to allow blood to flow out of the left atrium and close tightly to make sure no blood flows back into that chamber.

Leaflets with extra tissue can buckle back into the atrium each time the heart contracts. When that happens, the leaflets may not close completely and blood can seep back into the atrium.

Although the condition is formally known as mitral valve prolapse, it also goes by other names, such as:

  • click-murmur syndrome
  • Barlow’s syndrome
  • balloon mitral valve
  • floppy valve syndrome

MVP is the most common heart valve abnormality seen in developed countries. The American Heart Association estimates that about 2 percent of the United States population has MVP. It also appears to be more common in women than in men.

Some people are born with MVP, and it tends to run in families. But MVP is also commonly seen in people with Marfan syndrome and other inherited connective tissue disorders.

Cardiovascular disease or serious infections of the heart may also injure the mitral valve and result in MVP. In many cases, the cause of MVP cannot be determined.

When a healthcare professional listens to your heart, the blood flow within the heart’s chambers makes a steady, predictable sound if the heart is healthy and functioning properly. The term “heart murmur” refers to an abnormal sound in the heart caused by chaotic or turbulent blood flow.

In the case of MVP, blood flowing back into left atrium — a condition known as mitral valve regurgitation — can cause a murmur.

The sound of an MVP murmur is a swishing or whooshing noise. Mitral valve leaflets that are too long or floppy to close properly can also make a clicking sound when they close, which is why MVP is sometimes referred to as click-murmur syndrome.

With mild MVP, there may be no obvious symptoms. However, during a routine physical exam, your doctor may listen to your chest with a stethoscope and hear a heart murmur (a sound in between heartbeats). This finding may lead to tests to determine what is causing it and whether it’s serious enough to require treatment.

Other symptoms that can indicate MVP include:

A physical examination and 2D echocardiography are the primary tools to diagnose MVP. Echocardiography is a noninvasive test that uses sound waves to create real-time, moving images of the heart that appear on a computer monitor. This reveals how well the heart valves are functioning and if the heart is properly filling with blood and pumping it out with each heartbeat.

Another commonly used test to is an electrocardiogram. This test uses electrodes placed on your chest to measure the heart’s electrical activity. Electrocardiography can diagnose or rule out an abnormal heart rhythm (arrhythmia) that may also be present with MVP.

Other tests include:

Treatment is usually not necessary in cases of mild MVP with no symptoms. When palpitations or chest pain are present, beta blockers may be prescribed to help your heart become less irritable and lower your blood pressure, if necessary.

If you are dealing with severe MVP, mitral valve repair or replacement may be recommended to help lower your risk of heart failure and other complications like arrhythmia or endocarditis.

Mitral valve repair or replacement may be considered if:

  • your symptoms worsen
  • mitral valve regurgitation significantly worsens
  • the left side of your heart becomes enlarged
  • you develop an arrhythmia
  • there is a decrease in your heart’s ejection fraction (the percent of blood in the ventricle pumped out with every heart contraction)

While some mitral valves can be repaired surgically or with catheter-based procedures, valves with severe regurgitation are typically replaced with a prosthetic valve. Advances in minimally invasive procedures are providing doctors and patients alternatives to open heart surgery, which offer shorter recovery times and other potential benefits.

A heart murmur, which can sound like a whooshing sound in between heartbeats, can sometimes be the first sign of MVP. This type of heart valve disease can be mild, with no impact on your overall health or life expectancy, or it can be more severe and require repair. But sometimes, an MVP murmur can be a signal that a serious heart condition has developed and needs to be treated as soon as possible.

If you experience symptoms of an MVP, see a medical professional to evaluate potential causes and get treatment.