Mitral valve prolapse

What Is The Mitral Valve?

The mitral valve controls the flow of blood between two chambers or "rooms," of the heart--the left atrium and the left ventricle. Normally, blood flows only from the upper chamber, the atrium, into the lower chamber, the ventricle.

When the heart relaxes between contractions, or beats, the two cusps, or flaps, of the mitral valve swing open to allow blood to flow freely from the atrium into the ventricle.

The mitral valve is attached by fibrous threads, or hinges, to the walls of the ventricle. These hinges keep the flaps from opening the other way. This prevents blood from returning to the left atrium and ensures the forward flow of blood into the blood vessels that carry it to the rest of your body.

What Is Mitral Valve Prolapse?

In mitral valve prolapse, or MVP, the hinges are not working properly. Rather than tightly snapping shut, the flaps move up into the atrium when the heart beats. This can allow blood flow from the ventricle back up into the atrium.

Mitral valve prolapse can be discovered during a regular exam. When listening to the heart with a stethoscope, the doctor may hear a crisp clicking sound, which is produced by the flap. If blood is flowing back up into the atrium, the doctor will hear a whooshing sound, which is referred to as a murmur. The severity of the dysfunction varies greatly among patients.

Thus, mitral valve prolapse covers a wide spectrum of illness, ranging from simple prolapse with no apparent risk of complications to severe prolapse with a high risk of serious complications. Most children as well as adults with MVP are asymptomatic, meaning without symptoms.

What Are The Symptoms?

Though all do not, some children with mitral valve prolapse will have symptoms that go along with the condition. One symptom is palpitations, or feeling like the heart is racing or skipping beats. Others include chest pain from time to time, shortness of breath, dizziness, fatigue, and anxiety. Some children with mitral valve prolapse experience panic attacks, but because mitral valve prolapse and panic attacks are relatively common, coexistence of the two disorders would be expected to frequently occur by chance rather than in a cause-and-effect relationship.

About one in twenty people in the United States has MVP. It is a congenital defect which means that children are usually born with it More girls than boys have MVP. For a significant number of children with mitral valve prolapse, the condition seems to the inherited.

Properly Diagnosing The Condition

A doctor begins to first suspect MVP on the basis of cardiac auscultation, or listening to the heart with a stethoscope. Usually the child has no symptoms of MVP. Doctors must avoid the temptation to diagnose mitral valve prolapse on the click or murmur alone since not everyone with the click or the murmur has the condition.

The electrocardiogram, or EKG, may be normal in children with mitral valve prolapse. Although arrhythmias, or irregular beats, may be the seen on the EKG, they are more reliably detected by the Holter Monitor, a 24 hour continuous electrocardiographic recording. The most useful noninvasive procedure for diagnosing mitral valve prolapse is an echocardiogram, a test that uses sound waves to look at the heart and how it is working.

Prognosis and Complications

Fortunately, great advances in our knowledge of the diagnosis and natural history of mitral valve prolapse have occurred in the past few decades. Traditionally, the diagnosis of mitral valve prolapse has caused much alarm in parents. However, most studies now suggest that MVP has a complication rate of less than 2%. The age-adjusted survival rate in both males and females with mitral valve prolapse is similar to that of people without the condition.

Clearly, if your child is diagnosed with mitral valve prolapse, there's no need to panic. For example, it may be reassuring to know that a study published two years ago based on 3,500 subjects from the highly regarded Framingham Heart Study found that people with mitral valve prolapse do not seem to be more likely than those without the condition to have heart failure, stroke, heart arrhythmias, or episodes of fainting--all of which were once thought to be common complications of MVP.

If your child has been diagnosed with mitral valve prolapse and does not experience symptoms, the doctor may recommend that he or she be reevaluated every 3 to 5 years or so to monitor the condition and make sure that it is not progressing. If symptoms exist or develop, re-evaluation may take place on a yearly basis.

The most common risk of mitral valve prolapse is the development of a bacterial infection of the heart valve. As a result, the child may need to take an antibiotic before having dental work, surgery, or an invasive diagnostic procedure.

Management

In people with confirmed mitral valve prolapse, but whose valves are not thickened and there is no backflow of blood, most experts feel that no treatment is necessary. For those with mitral murmurs, the prophalactic antibiotic works very well.

The American Heart Association provides wallet sized cards for patients to carry explaining the need for antibiotic prophylaxis, however usually parents simply inform their child's dentist and other physicians of their need for the medication.

If your child suffers from other MVP-related problems, the doctor may prescribe medicines that control the irregular heart beats, help the heart pump more effectively, or lessen shortness of breath.

In 2-5% of children with MVP, heart surgery is required. An artificial mitral valve is put in to replace the child's diseased one.

If your child has been diagnosed with mitral valve prolapse, be assured that they have a condition which is managed very effectively and which rarely leads to complications.

Rosemary Iconis, Ph.D., is an assistant professor at the City University of New York. She is a writer specializing in the areas of health and medicine. Her articles have appeared in many magazines and newspapers.

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