Mitral valve regurgitation

Mitral valve regurgitation is a heart valve condition in which the flaps of the mitral valve don’t close properly, allowing blood to flow backward instead of moving forward. These flaps, also called valve leaflets or cusps, control the flow of blood from the left atrium to the left ventricle. When they don’t close tightly enough or the valve’s size or shape changes, blood can leak in the wrong direction. This leak is also called mitral regurgitation (MR) or mitral valve insufficiency, and it’s the most common form of heart valve disease.

Penn Medicine’s interventional cardiology and heart valve disease care specialists are recognized nationally for innovative treatment approaches and strong outcomes for people with mitral regurgitation. Our surgeons and cardiologists treat routine and complex cases alike, and as one of the largest heart valve programs in the mid-Atlantic, we’re equipped to care for every stage of valve disease.

• Primary mitral regurgitation: Also called degenerative mitral regurgitation, this type happens when the valve itself is damaged. Its flaps droop, bulge, or don’t close tightly.
• Secondary mitral regurgitation: Also called functional mitral regurgitation, this type happens when a problem outside the valve, like a change in the left ventricle, causes the leak. Your valve flaps may look normal, but you can still be diagnosed with this type.

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: Your hands and feet 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.

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.

Beyond standard treatment options, Penn Medicine's interventional cardiology program researches and tests new transcatheter devices for treating mitral valve disease. If you qualify, you may have the option to take part in a clinical trial and gain access to investigational devices and procedures not yet widely available.