Mitral valve prolapse prevalence and complications: an ongoing dialogue.

Abstract

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 See p 1355 Since the early 1970s, echocardiography has been suggested to be the ideal method for noninvasively recording the movement of the prolapsing mitral leaflets.1 Unfortunately, the continually changing echocardiographic methods and criteria for diagnosis for MVP over the last 30 years have often obscured rather than enhanced our understanding of the disorder.5 During the past decade, new echocardiographic criteria for MVP have been established on the basis of an understanding of the 3-dimensional structure of the mitral valve.6 Recent studies that used these criteria have shed new light on the prevalence and complications of MVP in the general population,7 although less is known about the natural history of MVP as diagnosed by these new criteria. The report in this issue of Circulation by Avierinos et al8 expands our understanding by describing the clinical outcomes in a group of 833 asymptomatic patients with echocardiographic MVP monitored for a mean of 5.4 years. The study …