Mitral valve prolapse prevalence and complications: an ongoing dialogue.

Mitral valve prolapse (MVP) is generally understood to be the systolic displacement of an abnormally thickened, redundant mitral leaflet into the left atrium during systole.1 This valvular abnormality has been associated with mid-systolic clicks, late systolic murmurs, and serious complications such as bacterial endocarditis, severe mitral regurgitation, and sudden death.2 Unfortunately, our understanding of the prevalence, complication rate, and associations of mitral valve prolapse has been clouded by the use of varying techniques, changing diagnostic criteria, and conclusions drawn from highly selected referral populations. Despite this confusion, an understanding of the prevalence of mitral valve prolapse and the identification of subgroups most susceptible to complications remain important because MVP is the most common cause of valve repair/replacement for isolated mitral regurgitation in the United States,3 and the thickened leaflets form a recognized substrate for bacterial endocarditis.4