Mitral Regurgitation

In mitral regurgitation, blood leaks backward through the mitral valve each time the left ventricle contracts to pump blood into the aorta.

In older people, mitral regurgitation usually develops gradually (over months or years). But it may develop quickly (over hours or days). Most older people have mild mitral regurgitation, which does not require treatment.

Causes

In older people, mild mitral regurgitation slowly develops when calcium accumulates at the base of the mitral valve. Severe mitral regurgitation may be caused by heart attacks, degeneration of the valve (myxomatous valve disease), or infection of the heart valves (endocarditis). Regurgitation can develop quickly if the structures that support the valve tear because a heart attack occurs or because the structures have weakened over time.

Symptoms and Diagnosis

Mild mitral regurgitation may cause few or no symptoms. People may tire easily and feel short of breath only during physical activity. If the disorder worsens, people may notice an irregular, fast heartbeat (indicating atrial fibrillation). Heart failure may develop.

If regurgitation develops quickly, symptoms may develop and become severe quickly. Breathing becomes very difficult, and people feel as if their heart is racing. Severe heart failure may develop.

Doctors usually suspect the diagnosis on the basis of abnormal heart sounds, abnormalities in the pulse, and the results of echocardiography. Transesophageal echocardiography is needed only when regurgitation is severe and valve repair or replacement may be needed.

Treatment

Most people with mitral regurgitation are given warfarin (an anticoagulant) to prevent clots from forming. Other disorders (such as heart failure or atrial fibrillation) that are causing mitral regurgitation are treated. If regurgitation is mild, such treatment may make surgery unnecessary.

If symptoms are severe or if echocardiography detects substantial heart damage (even if no symptoms are present), the mitral valve may be repaired or replaced. Repair or replacement is usually recommended if heart failure has developed. The valve is repaired if possible. Repair of the mitral valve is safer than replacement of the valve, and people are likely to live longer and have fewer symptoms.

Many people with mild mitral regurgitation have a good outlook. However, mitral regurgitation may worsen, causing symptoms and eventually heart failure. Getting regular checkups, which may include echocardiography, is important.