Overview

Mitral valve prolapse occurs when the flaps (leaflets) of the heart's mitral valve bulge (prolapse) like a parachute into the heart's left upper chamber (left atrium) as the heart contracts.

Mitral (MY-trul) valve prolapse sometimes leads to blood leaking backward into the left atrium, a condition called mitral valve regurgitation.

In most people, mitral valve prolapse isn't life-threatening and doesn't require treatment or changes in lifestyle. Some people with mitral valve prolapse, however, require treatment.