Mitral Valve Disease

Mitral Valve Regurgitation

If left untreated, mitral valve regurgitation can lead to congestive heart failure, which currently affects nearly five million people in the United States. Treatment depends on the severity of the mitral valve's regurgitation, how far the mitral valve disease has progressed, and signs and symptoms of the disease.

Within a day, a team of heart valve disease specialists at Mayo Clinic coordinates the patient's diagnosis to provide a complete examination, diagnosis and extensive patient education — from patients who want to have a heart murmur checked out to those who have been told they have advanced mitral heart valve disease.

If surgery is indicated, a cardiac surgeon meets with the patient to thoroughly discuss surgical options and, in most cases, can perform the surgery the following day if that is what the patient prefers. Because Mayo Clinic is a major medical center conducting clinical trials and research on various aspects of heart valve disease, some patients may be eligible to participate in trials or take part in research programs at Mayo Clinic.

Symptoms

Signs and symptoms of mitral regurgitation depend on how severely and quickly the condition develops. Most often, mitral regurgitation is mild and develops slowly. Because no symptoms develop for decades, the patient may be completely unaware of even having this condition.

When signs and symptoms develop, they may do so gradually because the heart is able to compensate for the defect for some time. A first sign is usually when the patient's heart develops an abnormal sound, or heart murmur. Sometimes, however, the disorder develops quickly. In those cases, the patient may experience the abrupt onset of more severe signs and symptoms.

Indicators of mitral regurgitation include:

• Shortness of breath, especially with physical exertion or when the person lies down
• Fatigue, especially during increased activity
• Cough, especially at night or when lying down
• Awakening at night with shortness of breath
• Heart palpitations — sensations of a rapid, fluttering heartbeat
• Swollen feet or ankles

Causes

Any condition that damages the mitral valve can cause regurgitation, including:

Rheumatic fever
This is a complication of strep throat and was once a common childhood illness in the United States. It can damage the mitral valve, leading to mitral regurgitation later in life. Rheumatic fever can damage the mitral valve in two ways. The infection may cause the leaflets of the valve to thicken, limiting the valve's ability to open. This results in narrowing of the valve (mitral stenosis). The infection may cause the leaflets of the mitral valve to fuse together, preventing the valve from closing tightly and leading to regurgitation. People who have had rheumatic fever may have both mitral stenosis and mitral regurgitation. Many older adults in the United States were exposed to rheumatic fever as children. Rheumatic fever is still prevalent in underdeveloped countries.

Deterioration of the valve with age
The mitral valve opens and shuts tens of thousands of times a day, every day of a person's life. Mitral regurgitation may result from age-related wear and tear on the valve. Mayo Clinic has extensive experience successfully treating elderly patients who have mitral regurgitation.

Prior heart attack
A heart attack can damage the area of the heart muscle that supports the mitral valve, affecting the function of the valve. In fact, if the damage is extensive enough, a heart attack may result in sudden and severe mitral regurgitation.

Mitral valve prolapse
Another problem of the mitral valve, mitral valve prolapse occurs when the leaflets and supporting cords of the mitral valve weaken. With each contraction of the left ventricle, the valve leaflets bulge (prolapse) up into the left atrium. This common heart defect may prevent the mitral valve from closing tightly and lead to regurgitation. However, mitral valve prolapse is common and the vast majority of people who have it never develop severe regurgitation.

Damaged cords
Mitral regurgitation may result from damage to the cords that anchor the flaps of the mitral valve to the heart wall. Over time, these cords may stretch or suddenly tear, especially in people who have mitral valve prolapse. A sudden tear of these cords can cause substantial leakage through the mitral valve and may require emergency heart surgery to repair.

Endocarditis
The mitral valve may be damaged by endocarditis — an infection inside the heart that can involve the heart valves. Read more about endocarditis prevention.

Congenital heart defect
Some infants are born with defects in their heart, including a mitral valve that leaks.