Health Library

What Is Mitral Valve Prolapse?

Mitral valve prolapse is a common heart condition. It happens when there’s a problem with how one of the heart’s valves works. Heart valves keep blood moving through the heart.

Even though it involves the heart, it’s not a serious health problem. Most kids who have the condition don’t have symptoms or need special medical care.

What Happens in Mitral Valve Prolapse?

The mitral (MY-trul) valve is between the left atrium and the left ventricle. It helps make sure that blood flows in one direction only as it passes from the left atrium into the left ventricle:

Each time the heart beats, the left ventricle pumps blood out to the body.

The mitral valve has two flaps (or “leaflets”) of tissue that swing shut to prevent the blood in the ventricle from flowing backward into the left atrium.

In mitral valve prolapse, one or both flaps bulges back into the atrium when they shut, a bit like a balloon. This may happen because the flap has an unusual shape or is a little too big.

What Are the Signs & Symptoms of Mitral Valve Prolapse?

Mitral valve prolapse usually doesn’t cause symptoms or affect everyday life. Many cases aren’t found until someone is an adult.

Kids who do get symptoms might:

• feel dizzy or lightheaded
• be very tired
• feel short of breath or have trouble breathing after being very active
• feel that the heart is skipping beats or beating very quickly
• have chest pain that comes and goes

What Causes Mitral Valve Prolapse?

In most cases, the cause of mitral valve prolapse isn’t known. Sometimes kids are born with the condition. Others develop it after an inflammatory condition, like:

• endocarditis: an infection of the inner lining of the heart
• rheumatic fever: inflammation that can affect the joints and the heart

Mitral valve prolapse sometimes happens with health conditions that involve the body’s connective tissue (tissue that supports organs and other tissue), such as Marfan syndrome and Ehlers-Danlos syndrome. Some kids also might have an arrhythmia, or irregular heartbeat.

How Is Mitral Valve Prolapse Diagnosed?

Sometimes, the flaps of the mitral valve make a sound when they close, like when you flick or snap a towel, called a “click.” A doctor might hear this noise when listening to the heart with a stethoscope and find the condition that way.

If the flaps do not close evenly or fit together well, blood can leak back into the left atrium. This is called mitral regurgitation. When there’s more than a little leakage (a “leaky valve”), the doctor may hear a whooshing sound as some blood moves backward into the left atrium. This is a heart murmur, and it’s heard between the normal lub-dub sounds of the heartbeat. 

When a click and murmur are heard together, the click happens first (as the flaps close and flop back), followed by the murmur (the sound of the blood leaking back into the atrium).

In kids, doctors might find mitral valve prolapse during a regular checkup. When listening to the heart with a stethoscope, the doctor might hear a click or a murmur. If so, the doctor will send the child to a pediatric cardiologist, a doctor who diagnoses and treats heart conditions in kids.

The cardiologist will do an exam, listen to the heart, and possibly order tests such as:

• an echocardiogram (echo), which uses sound waves to create a picture of the heart and its blood flow. If a child has mitral valve prolapse, the bulging valve flaps usually are seen when the heart beats.
• an electrocardiogram (EKG or ECG), which records the heart’s electrical activity 

How Is Mitral Valve Prolapse Treated?

Kids with mitral valve prolapse don’t need medical treatment. If the condition causes a lot of mitral regurgitation, doctors may prescribe blood pressure medicine to control how hard the heart muscle works. (With blood leaking back into the atrium, the heart works harder to pump the normal amount of blood out to the body.)

A child who has an arrhythmia along with mitral valve prolapse may need to take medicine to help regulate the heart’s rhythm. But this is uncommon in kids.

Leakage from a mitral valve prolapse may go on for years. Rarely, a child might need surgery to repair a very leaky mitral valve. Later in life, someone might need their mitral valve repaired or replaced if:

• Their symptoms get worse.
• The left ventricle gets enlarged.
• The condition affects how well their heart works.

Preventing Heart Infection

Kids who have mitral valve prolapse and a leaky valve have a small risk of a bacterial infection of the heart valve (infective endocarditis). It very rarely happens during childhood. Many times the bacteria that cause this kind of infection start out living in the mouth and enter the bloodstream through the gums.

Doctors used to recommend that people with mitral valve prolapse take antibiotics before dental work and surgical procedures as a precaution. This is no longer the case.

Instead, kids should focus on good oral care and:

• Brush their teeth twice a day, morning and night (after eating).
• Floss every night.
• See their dentist every 6 months.

How Can Parents Help?

Kids with mitral valve prolapse who have no other medical conditions usually don’t need special medical care. Those who want to play sports can do so if:

• They don’t have mitral regurgitation.
• Their mitral valve prolapse isn’t causing symptoms.

Kids with a leaky valve or symptoms need their doctor’s OK to play sports. This may involve getting more tests.

Any heart condition can cause worry. But mitral valve prolapse isn’t likely to affect your child’s everyday life and activities. If you have any questions or concerns, speak with your doctor.