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Mitral Regurgitation


The Manual's Editorial Staff

Last full review/revision Feb 2021| Content last modified Feb 2021
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What is mitral regurgitation?

Four heart valves control how blood flows in and out of your heart. The valves are like one-way doors that keep blood flowing in the right direction.

Your mitral valve separates your left atrium and left ventricle. This valve opens to let blood from your lungs out of your left atrium and into the left ventricle. The valve closes to keep blood from rushing back into your left atrium.

Mitral regurgitation is when the mitral valve doesn't close all the way. When your left ventricle contracts to pump blood to your body, some of the blood instead leaks backward into the atrium.

  • Mitral regurgitation is usually caused by genetic conditions (passed down in your family) or by a heart attack

  • The more blood that leaks backward, the harder your heart has to work to pump out enough blood

  • Eventually, your heart has to pump so hard to compensate for the leak that you develop heart failure

  • Doctors can hear a heart murmur through a stethoscope and do echocardiography to diagnose mitral regurgitation

  • Mild regurgitation may not cause any symptoms or need treatment

  • Severe regurgitation can cause symptoms, such as shortness of breath, or an abnormal heart rhythm, such as atrial fibrillation

  • For severe regurgitation, your mitral valve will need to be repaired or replaced

Atrial fibrillation can cause problems such as blood clots or stroke.

What are the causes of mitral regurgitation?

Mitral regurgitation can develop suddenly or gradually.

Causes of sudden mitral regurgitation include:

Causes of gradual mitral regurgitation include:

What are the symptoms of mitral regurgitation?

You may not have symptoms from mild mitral regurgitation.

Severe mitral regurgitation can cause heart failure, which may cause you to:

  • Get tired easily

  • Feel short of breath

  • Have swelling in your legs

Atrial fibrillation may cause:

  • Palpitations (feeling your heart pounding, fluttering, racing, or skipping beats)

  • Shortness of breath

How can doctors tell if I have mitral regurgitation?

Doctors suspect mitral regurgitation by listening to your heart with a stethoscope. Doctors use echocardiography (an ultrasound of your heart) to find out how bad the leak is.

Doctors may also do tests to see the left atrium and ventricle, such as:

  • Electrocardiography (ECG/EKG) (a quick, painless test that measures your heart’s electrical currents )

How do doctors treat mitral regurgitation?

Mild mitral regurgitation may not need treatment. Doctors may check on your heart occasionally with echocardiography.

Doctors will monitor your symptoms and repeat the echocardiography to decide when to do surgery. Your mitral valve should be surgically repaired or replaced before your heart muscle is damaged.

If your valve is seriously damaged, doctors can do surgery to replace the valve with:

  • A plastic, mechanical valve

Sometimes doctors replace heart valves with a valve from a pig or cow heart. However, doctors prefer to use a mechanical valve when replacing the mitral valve. If you get a mechanical valve, you'll need to take blood-thinning medicine for the rest of your life, but the valve may last several decades.

People with damaged or replaced valves sometimes need antibiotics to prevent heart valve infection, such as when they:

  • Get dental work

  • Have certain medical procedures

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