The heart is a muscle about the size of a fist and consists of four chambers and four heart valves, which keeps the flow of blood moving in only one direction. The American Heart Association states approximately 5 million Americans are diagnosed with heart valve disease annually.
The mitral valve lies between the atrium and ventricle on the left side of the heart, which has two flaps (or leaflets). If one or both of the flaps bulges backward, this is called prolapse and can cause regurgitation of blood up into the top chamber of the heart. Mitral valve prolapse (MVP) is also known as the “click-murmur syndrome.” The tricuspid valve is on the right side of the heart and has three flaps, which can also get disease. The aortic and pulmonic are the other two heart valves. Mitral valve prolapse is the most common type of valve disease.
There are different types of mitral valve prolapse diseases. Barlow’s Syndrome is a mitral valve prolapse disease, which affects about 200,000 people. This syndrome is characterized by a floppy mitral valve, which can involve one or both flaps of the valve. This syndrome causes a heart murmur, but the individual usually has no symptoms.
The exact cause of this disease is unknown, although it can be genetic. Marfan’s syndrome, a disorder of the connective tissue, causes problems with the joints, may cause an aneurysm in the aorta, and it also causes mitral valve prolapse.
There are two major types of mitral valve prolapse, classic and non-classic MVP. Classic MVP is the more dangerous of the two, but it is less common. The classic form can cause severe regurgitation, which may lead to congestive heart failure and endocarditis. This is an inflammation of the interior lining of the valves and heart. Non-classic MVP seldom causes a significant problem.
Congenital heart valve disease occurs before a child is born, and there may be an improper valve size, malformed valve leaflets or the leaflets may be attached irregularly. Congenital valve disease typically affects the aortic or pulmonic valve. Bicuspid aortic valve disease is one type of congenital heart valve disorders, as the aortic valve has only two leaflets instead of the normal three, which may cause the valve to leak as the leaflets cannot close tightly.
There are also acquired valve diseases due to infections, which are Rheumatic fever and infectious endocarditis. Children get Rheumatic fever due to an untreated strep throat. Endocarditis infections may occur after dental procedures, surgery, severe infections and intravenous drug use. Each of these infections may cause the valves to leak or to become stenotic (narrowed).
A physician may diagnose MVP if they hear the “click murmur” that indicates MVP. Echocardiograms are ordered to diagnose MVP. A stress echogram is often ordered to look for decreased blood flow to the heart. The Doppler ultrasound is a part of the echocardiogram, and it reflects the speed and direction of mitral valve blood flow. An EKG is done to look at the heart’s electrical rhythm and heart rate. A chest x-ray is ordered to look for fluid in the lungs and to see if the heart is enlarged.
Many people have mild mitral valve prolapse and do not experience symptoms. Symptoms occur with regurgitation, which is blood leaking backward through the valve. While symptoms may vary greatly between individuals, there are some common ones.
Common mitral valve prolapse symptoms:
- An irregular heartbeat (arrhythmias), palpitations or a racing heart
- Shortness of breath or difficulty breathing – lying down or exercising
- Lightheadedness or dizziness
- Swollen feet and ankles
- Chest discomfort that is not due to a heart attack or coronary artery disease
- Excessive urination
- Migraine headaches
While the symptoms may begin mildly, they can worsen over time.
As most people with MVP do not have complications, no treatment is necessary. The people that have regurgitation or backflow through the mitral valve typically require some form of treatment. The goal of treatment is to prevent infections, to relieve symptoms or correct the underlying problem with surgery.
There are several medications that may be prescribed for people with symptoms, such as palpitations or chest discomfort. The type of symptoms will determine which medications are necessary.
Some of the most common medications include:
- Beta blockers – this group of medications treat irregular heartbeats and slow the heart rate
- Digoxin – strengthens each heartbeat
- Diuretics – removes excess fluid from the lungs
- Anticoagulants (blood thinners) – medications (Coumadin or aspirin) to prevent blood clots that occur with atrial fibrillation (a possible arrhythmia)
- Vasodilators – widens blood vessels and reduces the heart’s workload
- Regulators of heart rhythms – flecainide and procainamide
When medication fails to control the MVP symptoms, surgery is the next step. Mitral valve repair is the preferred surgery whenever possible. The second option is mitral valve replacement, using a mechanical valve or a biological one.
Most of the people that have MVP are born with it and lead a normal life. Anyone with MVP symptoms should see a doctor.