Mitral Valve Prolapse
Basic Information
Mitral valve prolapse is a condition in which the mitral valve does not seal properly. It is also known as "Barlow's syndrome", "floppy mitral valve", "myxomatous mitral valve", "billowing mitral valve", and "systolic click-murmur syndrome".
There are four valves in the heart, including the mitral valve. This valve connects the left atrium (or the upper left chamber) and the left ventricle (or the lower left chamber). As the mitral valve opens and closes, it is able to regulate the flow of blood. When it opens, it circulates blood between these two chambers. When it closes as the left ventricle contracts, it forces blood out of the heart.
When a person has a mitral valve prolapse, their mitral valve does not close tightly. This can cause the valve to bulge back into the left ventricle during the heart's contraction. This is often referred to as "billowing". If the mitral valve "billows" and bends back into the left ventricle, it often produces a slight clicking sound that can be detected by a stethoscope.
Sometimes, billowing can also allow a small leakage of blood to flow back into the left atrium. Not all persons with this condition experience leakage of the valve. At the same time, when there is leakage, the extent of leakage varies greatly from case to case. Typically, it just leaks a little. This leakage of blood often results in a heart murmur, which is an abnormal heartbeat often caused by some structural defect of the heart. Not all people with mitral valve prolapse develop heart murmurs. Even when people do develop heart murmurs, they are not life-threatening. In almost all cases, because the heart's blood supply is not reduced significantly by the loosened mitral valve, the heart continues to function normally. Also, unlike many other valve conditions, mitral valve prolapse is not a progressive disorder. It ordinarily does not worsen over time.
In most cases mitral valve prolapse is simply an annoying condition that can be controlled with medical treatment. About 5 percent of mitral valve prolapse cases progress into further complications.
Mitral valve prolapse is the leading health problem affecting the heart. It is estimated that between five and twenty percent of all Americans experience mitral valve prolapse to some extent.
This complication does not discriminate between ethnicities, and people of all ages may be affected. There is some evidence that women are more affected than men. However, men who develop mitral valve prolapse are more likely to experience complications.
Most doctors think that mitral valve prolapse is a genetic disorder. There is strong evidence suggesting that this condition is genetically inherited as a dominant gene. However, it is important to understand that mitral valve prolapse is not necessarily related to coronary artery disease or other cardiac problems. If a person has a family medical history that includes cardiac diseases, it does not mean that there is a greater chance that they will develop mitral valve prolapse. Concurrently, if a person develops mitral valve prolapse, it will not necessarily develop into coronary artery disease or other heart complications.
Risk factors of mitral valve prolapse include minor chest wall deformities, scoliosis, atrial septal defects, fatigue, overwork, and pregnancy. Pregnancy places a person at higher risk of developing this condition because it increases blood volume and to some extent overworks the heart.
Symptoms
It is not uncommon for people with mitral valve prolapse to be asymptomatic. An estimated sixty percent of all mitral valve prolapse cases do not exhibit symptoms. If there are symptoms, they often develop gradually over time. They may vary from mild to severe. The most common symptoms of mitral valve prolapse include:
- increased sensitivity to feeling the heart beat (called a palpitation)
- chest pain (happens more frequently when at rest than during exercise)
- cough
- feeling of weakness, tiredness, fatigue
- panic attacks (a sudden feeling of anxiety)
- shortness of breath (particularly when lying down or during exertion)
- irregular heartbeat or feeling that the heart stops beating for a moment
- tachycardia (when the heartbeat suddenly becomes rapid)
- a sensation that the heart is pounding
- lightheadedness or dizziness when standing upright
There is some evidence that symptoms are more likely to appear in association with a stressful or traumatic event. These events include: job problems, marital problems, childbirth, or viral attack.
Diagnosis/Treatment
If a person does not notice any symptoms but has this condition, it can usually be detected during a regular physical examination. It is sometimes diagnosed during pregnancy. There are several tools that a doctor can use in order to diagnose mitral valve prolapse. When an affected person goes to the doctor, the first thing the doctor will be concerned with is the history of the symptoms. If the doctor feels it is necessary, they will perform diagnostic tests. In most cases they will use a test known as an "echocardiogram". This test utilizes sonar technology by bouncing high-frequency sound waves off of the organs and tissues of the body, and then using a computer to scan these sound waves and create a composite image of the interior of the body. This test is also referred to as an "sonogram". The image is a high-resolution picture of the heart structure including the mitral valve. From this image, doctors can both detect mitral valve prolapse and assess the extent of the structure abnormality. This test is completely painless and non-invasive.
An echocardiogram can be taken in the doctor's office and generally lasts about twenty minutes. During the test, the patient will lie down on a table. They may be given certain liquids that will provide contrast in the image, and this can make the image even more clear. It is also possible to monitor the heart during this test. Rather than creating a single image, echocardiogram monitoring allows the doctor to observe the heart for an extended period of time.
A doctor may also perform a stethoscopic examination. While this kind of test is not specific enough to be used to make the diagnosis, it can detect abnormal heartbeat rhythms. This test involves placing a stethoscope over the heart and listening to the amplified heartbeat. If a person has mitral valve prolapse, the doctor may hear a heart murmur during a stethoscopic examination. When there is a heart murmur present, a doctor will hear a click-sound halfway through the beating part of the heartbeat cycle, followed by murmur towards the termination of the cycle.
Often the heart murmur sounds worse when the person is standing up.
Another test that may be used is the metabolic exercise test. This test not only can detect the presence of a more severe heart complication, but also reveals how well the heart functions during physical exertion. This is important so that doctors can know if it is safe for the affected person to exercise or not. This allows doctors to recommend an appropriate level of fitness training.
Other tests that may be used as secondary diagnostic tools include chest x-rays, coronary angiography, and ECG's.
Typically, mitral valve prolapse does not need treatment. Because it rarely worsens over time and it does not affect cardiac function, there is nothing to treat. At the same time, because it is often asymptomatic, there are not even symptoms to alleviate.
It is very important that people with mitral valve prolapse maintain a well-balanced, nutritionally enriched diet. Not only will a good diet reduce any feelings of fatigue, but there is some evidence that poor diet can agitate this condition. It is suggested that people with mitral valve prolapse cut caffeine out of the diet, and decrease their sugar intake. Although sugar can be used to deal with low-energy it is recommended that affected persons have a mid-day high-protein snack instead. Both sugar and caffeine disturb the body's autonomic nervous system and can agitate fatigue and other symptoms of mitral valve prolapse.
A person should also drink plenty of fluids. Many of the symptoms associated with mitral valve prolapse are caused by low blood pressure and low blood volume, which can be countered by sufficient fluid intake.
In most cases, persons with mitral valve prolapse are not physically fit. Once doctors determine what level of exercise training is suitable to the affected person, it is important that the person regularly exert themselves. Not only will this improve the person's sense of well-being, but it will also relieve symptoms. It is suggested that the exercise should be aerobic in nature. Walking in particular is recommended.
If symptoms are severe or if the condition continues to worsen, doctors may perform surgery. In most cases, they will perform a procedure that is known as a "valve replacement". A valve replacement consists of removing the leaky valve and replacing it with an artificially- manufactured valve. Surgery may also be necessary if mitral valve prolapse is adversely affecting cardiac function.
In some serious cases, medications can be taken in the place of surgery. There are several kinds of medications that are used to treat the symptoms of mitral valve prolapse. If the person is experiencing abnormal heart rhythms, the doctor may prescribe antiarrhythmics. Digitalis may be used to increase the strength of the heartbeat. Vasodilators help the heart accommodate for any extra work it has to do because of the leaky mitral valve. Analgesics may be needed for chest pain.
Rarely, a person with mitral valve prolapse develops endocarditis. Endocarditis is a bacterial infection in the mitral valve. A high risk factor for developing endocarditis is if the mitral valve is leaking a large amount of blood. This is because the leakage adversely affects the drainage system of the heart, which means that bacteria can remain in the heart for long periods of time. Although this condition is rare, it is difficult to treat and can be severe. If a person is at risk, it is very important that they undergo antibiotic prophylaxis. This means that the person must take certain antibiotics any time they require dental work or minor surgery in order to prevent bacterial infections. Antibiotic prophylaxis is necessary during these procedures because these procedures can allow bacteria to enter the bloodstream, which can then infect the debilitated mitral valve.
In most cases, mitral valve prolapse is harmless and asymptomatic. When there are symptoms present, they are easily treated with medication and lifestyle changes. In serious cases, surgery may be necessary in order to repair the leaky mitral valve and relieve symptoms.