Between those two chambers on the left side—your left atrium and left ventricle—is the mitral valve. This valve opens to allow blood into the left ventricle, then closes again to keep blood from flowing backwards into the left atrium or the lungs.
Understanding mitral valve prolapse
Craig Selzman, MD, a cardiothoracic surgeon and chief of the Division of Cardiothoracic Surgery at University of Utah Health, explains that the mitral valve is like a saloon door that swings open and close to separate the lungs from the main pumping chamber. If the saloon door swings backward into the saloon, blood flows the wrong way back into the lungs, which makes people short of breath and makes the heart work a lot harder to pump blood out.
The mitral valve is very complex. The leaflets on either side are connected to the lower chamber of the heart with small cords—kind of like parachute cords, according to Selzman. When the mitral valve leaflets close, the cords tighten to keep it from swinging too far. If any of these parts are damaged or not working properly, you can experience a mitral valve leak (also sometimes called mitral valve regurgitation).
One of the most common causes for mitral valve leaks is a condition called mitral valve prolapse (MVP). This occurs when one or both leaflets bulge or "balloon" so they can't form a tight seal in the middle. That leaves enough space for some of the blood to go back through to the left atrium, and in some cases, back to the lungs.
Symptoms of mitral valve prolapse
Some people might have mitral valve prolapse without any symptoms at all, while others might experience symptoms ranging from mild to severe.
Mild symptoms usually include:
- Shortness of breath
- Dizziness during exercise or exertion
- Heart palpitations or irregular heartbeat
- Feeling that your heart is "racing"
As the condition becomes more severe, your symptoms can get worse. You may notice:
- Significant swelling in your legs and feet (a condition called edema)
- Severe chest congestion
- Cough
- Difficulty breathing or catching your breath
- Bloating in the abdomen area
What causes mitral valve prolapse, and who's at risk
Anyone can develop mitral valve prolapse, although it is more likely to occur in men over the age of 50. It is often the result of a genetic condition so it tends to run in families and might be linked to:
- Ehlers-Danlos syndrome
- Muscular dystrophy
- Marfan syndrome
- Graves' disease
- Ebstein anomaly
- Scoliosis
You are more likely to develop symptoms if your mitral valve has extra tissue, which causes the valve to stretch or balloon. You can also develop MVP when the cords that are supposed to keep the valve from swinging too far either break or get stretched out.
When to see a doctor about mitral valve prolapse
There are people who have MVP without many (or any) symptoms. In that case you will probably never know that you have it unless it is revealed in an echocardiogram (echo), which is a diagnostic tool used to look at your heart. Your doctor probably won't recommend any treatment if you don't have any symptoms or issues.
You should see your primary care physician or a cardiologist if you experience symptoms thought to be related to mitral valve prolapse. For example, if you frequently have shortness of breath or irregular heartbeats, mention it to your primary care physician during your next annual check-up. You can also schedule an appointment sooner if your symptoms are severe, and you should definitely see a doctor right away if symptoms are getting worse.
If your doctor hears an irregular murmur with their stethoscope, they will probably order an echocardiogram imaging test to confirm whether you have MVP.
Treatments and potential complications for mitral valve prolapse
The most common treatment option for people with severe MVP is surgery. There are two options your doctor may discuss with you if he or she thinks you should have surgery:
- Mitral valve repair: A surgeon repairs your own mitral valve to get the leaflets to close properly.
- Mitral valve replacement: A surgeon replaces your mitral valve with a new one made of metal or tissue from an animal donor.
With both of these surgical procedures, there are different ways the surgeon can approach it, including:
- Full sternotomy - The surgeon makes a large incision in the center of your chest to access your heart through the sternum (commonly referred to as "open heart surgery").
- Partial sternotomy - Similar to a full sternectomy, but the surgeon makes a smaller incision in just the upper part of the sternum to access your mitral valve.
- Right thoracotomy - The surgeon makes several very small incisions around your ribcage and uses special instruments to repair or replace your mitral valve. This procedure is still an "open heart" surgery because the surgeon is repairing or replacing a valve inside your heart, but it is minimally invasive, so recovery is usually quicker and less painful than a full or partial sternectomy.
- Transcatheter mitral valve repair - The surgeon places a device called a MitraClip® around your mitral valve to reduce leakage and help with symptoms. This procedure is only recommended for patients who are at higher risk and cannot have traditional open heart surgery.
The specific type of surgery that will work best for you depends on several factors. Your doctor will review your medical history and whether they think they can repair your existing mitral valve, or if it will require a full replacement. It's important to talk to your doctor about what you can expect before, during, and after the surgery to properly prepare for it.
If you need a mitral valve replacement you will have to be on a blood thinner for at least several months, and possibly for the rest of your life. As with any surgical procedure, the most common complications from a mitral valve repair or replacement surgery include risks of:
- Bleeding
- Infection
- Stroke
Mitral valve repairs may also fail, and if they do you will need an additional surgery to replace your mitral valve at a later time.
Finding the right care to treat mitral valve prolapse
According to Selzman, not every cardiac surgeon knows how to perform a mitral valve repair or replacement surgery. Even those who do it a few times a year might not have a lot of experience, which can increase the risk of complications. That's why it's important to seek out a medical center.