Mitral Valve Prolapse

What is mitral valve prolapse (MVP)?

Mitral valve prolapse, also known as click-murmur syndrome, Barlow’s syndrome, balloon mitral valve, or floppy valve syndrome, is the bulging of one or both of the mitral valve flaps (leaflets) 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 (regurgitation). This regurgitation may result in a murmur (abnormal sound in the heart due to turbulent blood flow). Mitral regurgitation (backward flow of blood), if present at all, is generally mild.

It is estimated that mitral valve prolapse occurs in less than 3 percent of the population.

What causes MVP?

The cause of MVP is unknown, but is thought to be linked to heredity. Primary and secondary forms of MVP are described below.

• primary MVP Primary MVP is distinguished by thickening of one or both valve flaps. Other effects are fibrosis (scarring) of the flap surface, thinning or lengthening of the chordae tendineae, and fibrin deposits on the flaps. The primary form of MVP is seen frequently in persons with Marfan’s Syndrome or other inherited connective tissue diseases, but is most often seen in persons with no other form of heart disease.
• secondary MVP In secondary MVP, the flaps are not thickened. The prolapse may be due to ischemic damage (caused by decreased blood flow as a result of coronary artery disease) to the papillary muscles attached to the chordae tendineae or to functional changes in the myocardium. Secondary MVP may result from damage to valvular structures during acute myocardial infarction, rheumatic heart disease, or hypertrophic cardiomyopathy (occurs when the muscle mass of the left ventricle of the heart is larger than normal).

How is MVP treated?

Specific treatment for mitral valve prolapse will be determined by your physician based on:

• your overall health and medical history
• extent of the disease
• your signs and symptoms
• your tolerance for specific medications, procedures, or therapies
• expectations for the course of the disease
• your opinion or preference

Treatment is not usually necessary as MVP is rarely a serious condition. Regular check-ups with a physician are advised.
Persons with rhythm disturbances may need to be treated with beta blockers or other medications to control tachycardias (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 may be recommended. This can be in the form of aspirin or warfarin (Coumadin®) therapy.

For the person with symptoms of dizziness or fainting, maintaining adequate hydration (fluid volume in the blood vessels) with liberal salt and fluid intake is important. Support stockings may be beneficial.

If severe mitral regurgitation resulting from a floppy mitral leaflet, rupture of the chordae tendineae, or extreme lengthening of the valve should occur, surgical repair may be indicated.