Mitral Valve Prolapse
What is mitral valve prolapse?
Mitral valve prolapse (MVP) is the bulging (or prolapse) of one or both of the mitral valve flaps into the left atrium when the heart contracts. When the flaps do not close properly, blood leaks backward. This is called regurgitation. Regurgitation may result in a heart murmur, an abnormal sound in the heart caused by turbulent blood flow. But, if regurgitation is present, it’s generally mild.
The mitral valve is located between the left atrium and the left ventricle and is made of two flaps. Normally the flaps are tightly closed by the chordae tendineae , which are small tendon "cords" that connect the flaps to the muscles of the heart). In MVP, the flaps enlarge and stretch inward toward the left atrium, sometimes "snapping" during heart contraction, and may allow some backflow or regurgitation of blood into the left atrium.
MVP usually does not need to be treated because it is rarely a serious condition, and it does not damage the heart. However, regular checkups with a doctor are advised.
What causes MVP?
The cause of MVP is unknown, but it’s thought to be inherited. There are two forms of MVP: primary and secondary.
Primary MVP means the mitral valve is abnormal because of one or more of these changes:
- One or both of the flaps are too large and thick
- The flap surfaces are scarred
- The tendon cords are thinner or longer than they should be
- There are fibrin deposits on the flaps
The primary form of MVP is seen in people with Marfan syndrome and other inherited connective tissue diseases, but it’s most often found in people with no other form of heart disease.
In secondary MVP, the flaps are not thickened. The prolapse or bulging may be due to:
- Damage caused by decreased blood flow (due to coronary artery disease) to the muscles attached to the tendon cords
- Functional changes in the heart muscle
- Damage to valve structures caused by acute myocardial infarction (heart attack), rheumatic heart disease, or hypertrophic cardiomyopathy (this is when the left ventricle of the heart is larger than normal)
Who is at risk for MVP?
MVP affects both sexes and people of all ages. Factors that may increase the risk of MVP include:
- Graves disease (a condition that affects the thyroid gland)
- Certain connective tissue disorders, such as Marfan syndrome
- Scoliosis and other skeletal problems
- Some types of muscular dystrophy
What are the symptoms of MVP?
MVP may not cause any symptoms. Symptoms may vary depending on the degree of prolapse present.
The following are the most common symptoms of MVP. However, each person may experience symptoms differently. Symptoms may include:
Palpitations. Palpitations (fast or irregular heartbeats) are the most common complaint in people with MVP. The palpitations are usually linked to premature ventricular contractions (the ventricles beat sooner than they should), but there may also be supraventricular rhythms (abnormal rhythms that begin above the ventricles). In some cases, people may have palpitations without having dysrhythmias (irregular heart rhythms).
Chest pain. Chest pain associated with MVP is different from chest pain associated with coronary artery disease and is a frequent complaint. Usually the chest pain is not like classic angina, but it can happen often, can be very uncomfortable, and can affect the person’s quality of life.
Depending on the severity of the mitral regurgitation or leak, the left atrium and/or left ventricle may become enlarged, leading to symptoms of heart failure. These symptoms include weakness, tiredness, dizziness, and shortness of breath.
The symptoms of mitral valve prolapse may resemble other medical conditions or problems. Always see a doctor for a diagnosis.
How is mitral valve prolapse diagnosed?
People with MVP often have no noticeable symptoms and a click or murmur may be heard during a routine physical exam. The "click" is created by the stretched flaps snapping against each other during contraction. The murmur is caused by the blood leaking back into the left atrium. The click or murmur may be the only sign of MVP.
Along with a complete medical history and physical exam, tests used to diagnose MVP may include:
Electrocardiogram (ECG). This test records the strength and timing of the electrical activity of the heart. It shows abnormal rhythms and can sometimes detect heart muscle damage. Small sensors are taped to your skin to pick up the electrical activity.
Chest X-ray. An X-ray may be done to check your lungs and see if your heart is enlarged.
Echocardiogram (echo).This is a noninvasive test that uses sound waves to evaluate the heart's chambers and valves. The echo sound waves create an image on the monitor as an ultrasound transducer is passed over the heart. Echocardiography is the most useful diagnostic test for MVP.
In some cases where symptoms are more severe, more tests may be done. These may include:
Stress test (also called treadmill or exercise ECG).This ECG is done while you walk on a treadmill to monitor the heart during exercise. Breathing and blood pressure rates are also checked.
Cardiac catheterization. With this procedure, X-rays are taken after a contrast agent (dye) is injected into an artery to look for any narrowing, occlusions (blockages), or other changes in certain arteries. The function of the heart and the valves may be checked, too.
Cardiac MRI. This is an imaging test that takes detailed pictures of the heart. It may be used to get a more precise look at the heart valves and heart muscle, or to prepare for heart valve surgery.
How is mitral valve prolapse treated?
Specific treatment for MVP will be determined by your health care provider based on the following:
- The extent of the problem
- Your age, overall health, and medical history
- Your tolerance for specific medications, procedures, or therapies
- Expectations for the course of the disorder
- The opinion of the health care providers involved in your care
- Your opinion and preference
MVP usually does not need to be treated because it is rarely a serious condition, and it does not damage the heart. Regular checkups with a doctor are advised.
People with heart rhythm changes may need to be treated with medicines to control fast heart rhythms. In most cases, limiting stimulants, such as caffeine and cigarettes, is all that is needed to control symptoms.
If atrial fibrillation or severe left atrial enlargement is present, treatment with an anticoagulant (blood thinner) may be recommended to keep clots from forming. This can be in the form of aspirin or warfarin (Coumadin) therapy.
For the person with symptoms of dizziness or fainting, staying well hydrated (keeping enough fluid in the body and blood vessels) is important.
If severe mitral regurgitation is due to a floppy mitral leaflet, rupture (tear) of the chordae tendineae, or extreme lengthening of the valve, surgical repair may be needed.
What are the complications of mitral valve prolapse?
MVP is usually harmless and does not shorten life expectancy. Healthy lifestyle behaviors and regular exercise are encouraged.
Rarely, bacteria that enter the bloodstream can cause endocarditis, an infection of the inner lining of the heart chambers and valves. This risk is higher in people with MVP because the deformed mitral valve flap can attract bacteria that are in the bloodstream. Gum infections and tooth decay can cause endocarditis, so regularly flossing and brushing your teeth can help prevent it. People at high risk for endocarditis (such as those who have had a valve replaced) may be given antibiotics before dental work and certain types of surgery.
When should I call my health care provider?
You should notify your health care provider if your symptoms get worse or if you have new symptoms.
- Mitral valve prolapse (MVP) is the bulging (or prolapse) of one or both of the mitral valve flaps into the left atrium during the contraction of the heart. One or both of the flaps may not close properly, allowing the blood to leak backward (called regurgitation).
- The cause of MVP is unknown, but is thought to be inherited.
- MVP affects both sexes and people of all ages. Some things that may increase the risk of MVP include Graves disease; certain connective tissue disorders, such as Marfan syndrome; scoliosis and other skeletal problems; and some types of muscular dystrophy.
- MVP may not cause any symptoms, and symptoms may vary depending on the degree of prolapse present. The most common symptoms include palpitations (fast or irregular heartbeats), chest pain, cough, and headaches.
- People with MVP often have a click or murmur that’s heard during a routine physical exam.
- MVP usually does not need to be treated because it is rarely a serious condition, and it does not damage the heart.
- People with heart rhythm changes may need to be treated with medicines to control tachycardias (fast heart rhythms).
- MVP is usually harmless and does not shorten life expectancy.
- Healthy lifestyle behaviors and regular exercise are encouraged. These include: eating a healthy diet, exercising regularly, maintaining a healthy weight, drinking only in moderation, and not using tobacco products
- Rarely, bacteria that enter the bloodstream can cause endocarditis, an infection of the inner lining of the heart chambers and valves. This risk is higher in people with MVP. People at high risk for endocarditis (such as those who have had a valve replaced) may be given antibiotics before dental work and certain types of surgery.
Tips to help you get the most from a visit to your health care provider:
- Before your visit, write down questions you want answered.
- Bring someone with you to help you ask questions and remember what your provider tells you.
- At the visit, write down the names of new medicines, treatments, or tests, and any new instructions your provider gives you.
- If you have a follow-up appointment, write down the date, time, and purpose for that visit.
- Know how you can contact your provider if you have questions.