Mitral valve regurgitation

Mitral valve regurgitation is a heart valve condition in which the flaps of the mitral valve do not close properly, causing a backward flow of blood back to the heart.

The flaps of the mitral valve (also called valve leaflets or cusps) control the flow of blood from the left atrium to the left ventricle through the valve. If not closed tightly enough or if the valve’s size and shape are altered, blood may leak in the wrong direction. This leak is also referred to as mitral regurgitation (MR) or mitral valve insufficiency and is the most common form of heart valve disease.

There are two types of mitral valve regurgitation:

• Degenerative mitral regurgitation: This occurs when the mitral valve itself is dysfunctional. The flaps may droop or bulge and do not close tightly.
• Functional mitral regurgitation: Functional mitral regurgitation happens when an issue outside of the valve (such as diseases of the left ventricle) causes the leakage. You may have normal valve flaps and still be diagnosed with functional mitral regurgitation.

Mitral valve regurgitation often evolves slowly with no noticeable symptoms. As the condition progresses, you may develop heart valve disease symptoms including:

• Shortness of breath: You may have trouble breathing, especially during exercise.
• Heart palpitations: You may notice a fluttering sensation in your heart, especially when lying on your left side.
• Swelling of hands and feet: Extremities may swell when blood flow is disturbed.
• Fatigue: You may tire easily, especially during physical exertion.

A variety of conditions can cause mitral valve regurgitation. Possible causes of a leaky mitral valve include:

• Mitral valve prolapse, a common heart defect in which the valve flaps bulge into the left atrium every time the heart contracts, preventing the valve from closing tightly
• Damaged tissue cords, which anchor the flaps of the mitral heart valve
• Rheumatic fever, a rare complication of strep throat
• Endocarditis, an infection that affects the heart’s lining
• Heart attack or coronary artery disease, both of which can damage the heart muscles surrounding the mitral valve
• Cardiomyopathy, a weakened heart muscle resulting from hypertension, heart attack, viruses or inherited disease
• Congenital heart defects, or structural heart issues present at birth

There are certain risk factors that can increase your chance of having mitral insufficiency. Some of these risk factors are within your control, such as the use of IV drugs (which can increase the risk of heart valve infections) and untreated strep throat or other listed conditions that can cause MR.

Your risk of mitral regurgitation may also be increased by factors that are out of your control, including genetic conditions, congenital heart defects and aging.

When your mitral valve leaks, there is not enough forward blood flow being maintained for the body to function as needed. This means that your heart needs to work harder to pump sufficient blood through the valve. The harder your heart needs to work to compensate for this loss, the more likely that subsequent heart conditions will occur. Untreated mitral valve regurgitation can lead to atrial fibrillation (AFib), heart failure and pulmonary hypertension.

To diagnose mitral valve regurgitation, your cardiologist will use echocardiography and cardiovascular imaging techniques including:

• Transthoracic echocardiogram (TTE)
• Electrocardiogram (ECG)
• Chest X-ray
• Cardiac magnetic resonance imaging (MRI)
• Exercise or stress tests

Mitral valve regurgitation is a progressive heart valve disease. The progression of this condition can be measured by the increase in regurgitated, or leaked, blood over time. The worsening of a mitral valve regurgitation case is often caused by a gradual reshaping of the valve as blood continues to leak. While many people with mitral regurgitation experience a worsening of their condition and related symptoms, some patients may also see a spontaneous improvement.

It is important to protect your heart health by continuing to visit your cardiologist for follow up appointments and echocardiograms as often as your doctor recommends — typically every six to twelve months depending on the severity of the leak.

If your mitral regurgitation is not causing symptoms, your cardiologist may recommend regular monitoring. If symptoms exist, medications may ease the discomfort.

Depending on the progression of your valve disease, Penn Medicine’s cardiac team may suggest repairing or replacing your valve with procedures including:

• Mitral valve repair and replacement surgery, which is performed as either traditional, open-chest surgery or minimally invasive heart surgery. Whenever possible, Penn surgeons operate on your valve robotically.
• Transcatheter mitral valve replacement (TMVR), which is a nonsurgical option for valve replacement used if your previously replaced mitral valve is leaking.
• MitraClip™, which is a catheter-based procedure used to repair functional mitral regurgitation, as well as degenerative regurgitation in high-risk patients.

In addition to offering traditional treatments for mitral insufficiency, our Interventional Cardiology program studies and tests innovative transcatheter devices developed to treat mitral valves. Select patients are candidates for investigational devices and procedures through clinical trials offered at Penn Medicine.