What is Mitral Valve Regurgitation?

What is Mitral Valve Regurgitation?

Mitral valve regurgitation is a disorder in which the mitral valve in the heart does not close properly, allowing some blood to leak backward. The mitral valve regulates the amount and direction of blood flow between the heart's two left chambers. If there is sufficient leakage at the mitral valve, extra strain is placed on the heart, and the lungs can get congested with blood. 

Mitral valve regurgitation is also referred to as mitral regurgitation, mitral incompetence, or mitral insufficiency. 

Types of Mitral Valve Regurgitation

Types

There are different types of mitral valve regurgitation:

  • Acute mitral valve regurgitation. Acute mitral valve regurgitation develops very quickly and can be life-threatening. Symptoms appear suddenly and are often severe. This type can result from damage to the mitral valve apparatus after a heart attack, an infection of the valve, or spontaneously.
  • Chronic mitral valve regurgitation. Chronic mitral valve regurgitation develops slowly and gradually. Symptoms may be barely noticeable initially but worsen over time if left untreated. This is often due to a failure of the heart's pumping chamber (left ventricle), causing the valve to be unable to close properly.
  • Trace mitral valve regurgitation. Trace mitral valve regurgitation is also known as mild mitral regurgitation, as it involves a very mild leak of the mitral valve. It usually does not cause additional complications. It is common and may not lead to subsequent problems.

Signs & Symptoms of Mitral Valve Regurgitation

Symptoms

Certain signs and symptoms can be indicators of mitral valve regurgitation. People with chronic mitral valve regurgitation may not experience symptoms immediately, and mild or moderate cases often do not show symptoms at all.

When mitral valve regurgitation symptoms are experienced, they may include:

  • Shortness of breath
  • Fatigue
  • Reduced ability to exercise
  • Heart palpitations, including a racing, pounding, or fluttering heart
  • Swelling in the feet, ankles, or legs
  • Heart arrhythmia (irregular heart rhythm)
  • Cough

What Causes Mitral Valve Regurgitation?

Causes

Mitral valve regurgitation is most commonly caused by a damaged mitral valve. This damage can result from a heart attack, a heart defect from birth, or another heart-related complication. If mitral valve regurgitation is due to problems with the actual mitral valve, the condition is called primary mitral valve regurgitation. Primary mitral valve regurgitation can look like floppy or drooping flaps in the mitral valve. 

Secondary (functional) mitral valve regurgitation occurs when there is an issue outside the mitral valve, like in the left ventricle or left atrium, preventing the valve from closing correctly. This can cause leakage, even though the valve flaps are normal.

Possible causes of mitral valve regurgitation include:

  • Mitral valve prolapse. A heart defect in which the leaflets (flaps) on the valve extend into the left atrium when the heart muscle contracts. This prevents the valve from closing tightly.
  • Cardiomyopathy. A condition in which the heart muscle fails. Cardiomyopathy can result from conditions such as hypertension (high blood pressure), heart attack, or infection; in some patients, no clear cause is identified.
  • Endocarditis. A very serious condition involving an infection of the heart valves that generally requires several weeks of antibiotics to treat
  • Heart attack. Heart attacks can result in damage to the heart muscle that supports the mitral valve, possibly leading to mitral valve regurgitation
  • Congenital heart defects. This includes any structural defects present from birth that prevent the mitral valve from closing properly
  • Rheumatic fever. An inflammatory condition that results when strep throat or scarlet fever is not properly treated. It can damage the heart and its valves, resulting in mitral valve regurgitation.
  • Damaged tissue cords. Small pieces of tissue anchor the flaps of the mitral valve to the wall of the heart. These tissues can tear or stretch over time, particularly in people with mitral valve prolapse.
  • Radiation therapy that is used to treat cancer in the chest area can cause mitral valve regurgitation
  • Calcium buildup. Calcium can accumulate on structures within the mitral valve, causing them to become less flexible and possibly preventing them from closing properly

Mitral Valve Regurgitation Risk Factors

Risk Factors

Certain genetic, environmental, and behavioral factors can increase a person's risk of mitral valve regurgitation. Risk factors include: 

  • Heart attack
  • Infections that affect the heart
  • Congenital heart defects
  • History of valve diseases, such as mitral valve prolapse 
  • Coronary heart disease or high blood pressure
  • Rheumatic heart disease
  • Radiation treatment to the chest
  • Older age 
  • Use of dexfenfluramine or fenfluramine–phentermine, which are drugs intended for weight loss that the FDA has since removed from the market for safety reasons

Complications

Complications

Mild cases of mitral valve regurgitation usually do not cause more complications. However, as the condition progresses, the heart must work harder to pump blood around the body, and this extra strain can weaken the heart over time and lead to issues such as: 

  • Atrial fibrillation (A-fib). A-fib occurs when the heart's upper chambers (the atria) do not contract in sync with the heart's lower chambers (the ventricles). Mitral valve regurgitation can cause the left atrium to increase in size, possibly leading to atrial fibrillation. This condition increases the risk of stroke, blood clots, and heart-related disorders.
  • Pulmonary hypertension. If not properly treated, mitral valve regurgitation can lead to increased pressure in the lungs' blood vessels
  • Congestive heart failure. When someone has mitral valve regurgitation, the heart has to work harder to pump blood around the body. Over time, this weakens the heart and if left untreated, it can lead to heart failure.
  • Bacterial infection of the heart valves. The likelihood of a valve infection increases with mitral valve regurgitation 
Get Care

Trust NewYork-Presbyterian for Mitral Valve Regurgitation Care

At NewYork-Presbyterian, our team of specialists is experienced in treating patients with mitral valve regurgitation. To learn about the treatment options available, visit our main treatment page.

Our doctors are also able to provide care and treatment services for aortic valve stenosis, tricuspid valve disease, and aortic valve regurgitation. Visit our main heart valve disease page for more information about the full range of services we provide.