 mitral valve prolapse (aka primary form of myxomatous degeneration of the mitral valve aka floppy mitral valve syndrome) is a valvular heart disease (aka systolic click murmur syndrome or billowing mitral leaflet syndrome), characterized by the displacement of an abnormally thickened mitral valve leaflet into the left atrium during systole. there are various types of mvp, broadly classified as classic and nonclassic. in its nonclassic form, mvp carries a low risk of complications and often can be kept minimal by dietary attention. in severe cases of classic mvp, complications include mitral regurgitation, infective endocarditis, congestive heart failure, and, in rare circumstances, cardiac arrest, usually resulting in sudden death. the diagnosis of mvp depends upon echocardiography, which uses ultrasound to visualize the mitral valve. the prevalence of mvp is estimated at 2-3% of the population. the condition was first described by john brereton barlow in 1966. in consequence, it may also be referred to as barlow's syndrome, and was subsequently termed mitral valve prolapse by j. michael criley. ==overview==  the mitral valve, so named because of its resemblance to a bishop's mitre, is the heart valve that prevents the backflow of blood from the left ventricle into the left atrium of the heart. it is composed of two leaflets, one anterior and one posterior, that close when the left ventricle contracts. each leaflet is composed of three layers of tissue: the atrialis, fibrosa, and spongiosa. patients with classic mitral valve prolapse have excess connective tissue that thickens the spongiosa and separates collagen bundles in the fibrosa. 
Valvular_heart_disease