Heart Explained

Heart valve disorders

Mitral valve regurgitation

What is mitral valve regurgitation?

First, a little information about your mitral valve and what it does:

Your mitral valve lies between your left atrium and your left ventricle. It has two leaflets that open to allow re-oxygenated blood to flow from your atrium into your ventricle. The leaflets close again when your ventricle contracts to push the blood into your aorta and out to the rest of your body.

The closing of your mitral valve prevents blood from flowing back into your atrium when your ventricle contracts.

Mitral valve regurgitation

For more information about what happens when your heart beats, take a look at How your heart pumps.

If you have mitral valve regurgitation, that means your mitral valve is leaking, and some of the blood in your left ventricle is being pushed back up into your left atrium again when your ventricle contracts. 

Mitral valve regurgitation is also known as mitral regurgitation or mitral insufficiency.  

Mitral valve regurgitation prevents your heart from pumping efficiently. It forces your heart muscle to work harder than it should and, if left untreated, it can lead to left heart failure.

Any kind of damage to the mitral valve can cause you to develop mitral valve regurgitation. The damage might be the result of a heart attack, an infection, or some kind of valve defect that has been present since birth. 

If your condition is severe you may need to have surgery to repair or replace your mitral valve.  

What causes mitral valve regurgitation?

Anything that damages your mitral valve can cause it to stiffen or weaken and can ultimately result in mitral valve regurgitation. Damage can be the result of an infection, a heart attack, or coronary artery disease, among other things.

Mitral valve prolapse, a condition where the valve leaflets, or flaps, are floppy and get pushed back into the atrium when the ventricle contracts, is the most common cause. If you have mitral valve prolapse, your valve will almost always leak, or regurgitate, some blood.  

Prior to the development of effective antibiotics, rheumatic heart disease was one of the most frequent causes of heart valve damage and, while now rare in the developed world, this is still a problem in developing nations.

In addition to these “primary” causes of mitral valve regurgitation, where the valve itself is the problem, there are “secondary” causes, where the valve is fine but the left ventricle has become enlarged, and the valve leaflets have been pulled apart as the ventricle has expanded. This is usually the result of some form of cardiomyopathy.

Common causes of mitral valve regurgitation include:

  • Mitral valve prolapse: The valve’s leaflets flop back into the atrium when the ventricle contracts and the valve then leaks
  • Rheumatic heart disease
  • Damage caused by a heart attack
  • Endocarditis: An infection of the heart’s chambers and valves 
  • Cardiomyopathy: An enlarged or weakened heart muscle
  • Rarely, a congenital heart defect

What are the symptoms of mitral valve regurgitation? 

If you have long-standing mild mitral valve regurgitation you may not really notice it, but if your condition worsens with time, or if you develop the disorder quite suddenly, you may experience severe symptoms.

Here are some common symptoms of mitral valve regurgitation. If you experience these symptoms you should immediately seek medical advice:

  • Shortness of breath when you exercise or lie down
  • Palpitations and a fast, fluttering heartbeat
  • Chest discomfort or pain

Mitral valve regurgitation may lead to left heart failure, and if that happens your symptoms may also include tiredness and swollen feet and ankles.

If you develop sudden, severe mitral valve regurgitation you may experience symptoms of shock, such as pale skin, fainting, and heart rhythm disturbances (arrhythmias). This is a medical emergency.

How is mitral valve regurgitation treated?

Your doctor will determine the best course of treatment for your mitral valve regurgitation based on the severity of your symptoms. 

If you have mild regurgitation you may not need any treatment at all. However, if your doctor is concerned and wants to make sure your condition doesn’t worsen, he or she may recommend one or more of the following treatments:

  • Medications to help dilate your blood vessels and decrease the burden on your left ventricle
  • Diuretics to reduce your fluid load
  • Blood-thinning medications to prevent clots (if you have developed an arrhythmia)
  • Surgery:  In severe cases, you may need surgery to repair or replace your mitral valve

What are the aims of treatment?

The aims of treatment for people with mild mitral valve regurgitation are to stabilize your condition and prevent it from worsening.  

If you experience symptoms of severe mitral valve regurgitation, and you need surgery, the aim is to restore normal valve function.