Mitral valve disease

Overview

In mitral valve disease, the mitral valve, which is located between your left heart chambers (left atrium and left ventricle), doesn't work properly.

Types of mitral valve disease include:

Mitral valve regurgitation

In this condition, the flaps (leaflets) of the mitral valve don't close tightly, causing blood to leak backward into the left atrium of your heart. If not treated, it can result in heart muscle damage.

This condition is commonly caused by mitral valve prolapse, in which the leaflets bulge back into the left atrium as your heart contracts.

Mitral valve stenosis

In this condition, the flaps of the mitral valve become thick or stiff, and they may fuse together. This results in a narrowed valve opening and reduced blood flow from the left atrium to the left ventricle.

Treatment for mitral valve disease depends on the severity of your condition and whether your condition is becoming worse. Your doctor may eventually recommend that you have surgery to repair or replace your mitral valve.

Symptoms

Some people with mitral valve disease might not experience symptoms for many years. Signs and symptoms of mitral valve disease may include:

• Abnormal heart sound (heart murmur) heard through a stethoscope
• Fatigue
• Shortness of breath, particularly when you have been very active or when you lie down
• Irregular heartbeat

When to see a doctor

If you have a heart murmur, your doctor may recommend that you visit a cardiologist. If you develop any symptoms that may suggest mitral valve disease, see your doctor.

Causes

Your heart has four valves that keep blood flowing in the correct direction. These valves include the mitral valve, tricuspid valve, pulmonary valve and aortic valve. Each valve has flaps (leaflets or cusps) that open and close once during each heartbeat. Sometimes, the valves don't open or close properly, disrupting the blood flow through your heart to your body.

In mitral valve disease, the mitral valve between the upper left heart chamber (left atrium) and the lower left heart chamber (left ventricle) doesn't work properly. It may not be closing properly, which causes blood to leak backward to the left atrium (regurgitation), or the valve may be narrowed (stenosis).

Mitral valve disease has many causes. Some forms of mitral valve disease can be present at birth (congenital heart defect).

Mitral valve regurgitation can be caused by problems with the mitral valve, also called primary mitral valve regurgitation. Mitral valve regurgitation is often caused by mitral valve prolapse, in which the mitral valve flaps (leaflets) bulge back into the left atrium. Diseases of the left ventricle can lead to secondary mitral valve regurgitation.

Mitral valve stenosis is often caused by rheumatic fever, which is a complication of a strep infection that can affect the heart.

Risk factors

Several factors can increase your risk of mitral valve disease, including:

• Older age
• History of certain infections that can affect the heart
• History of certain forms of heart disease or heart attack
• History of use of certain drugs
• Heart conditions present at birth (congenital heart disease)
• Radiation to the chest

Complications

Mitral valve disease can cause many complications, including:

• Irregular heart rhythms in the upper heart chambers (atrial fibrillation)
• High blood pressure that affects the blood vessels in the lungs (pulmonary hypertension)
• Blood clots
• Heart failure
• Stroke