Mitral prolapse occurs when excess mitral valve leaflet tissue or myxomatous degeneration of valve components causes the mitral valve leaflets to balloon into the left atrium during systole.
Anxiety and panic disorders have been associated with mitral valve prolapse.
Myxomatous degeneration is an increase in spongiosa (composed of dermatan sulfate) and a decrease in fibrosa (which has more tensile strength) which results in redundant valvular tissue.
Connective tissue disorders such as ehlers danlos, marfan, or osteogenesis imperfecta predispose to mitral valve prolapse. Turner syndrome
The majority of patients are asymptomatic, but some may complain of palpitations and chest pain.
Cardiac auscultation in patients with mitral valve prolapse (MVP) typically reveals a nonejection click due to snapping of the mitral chordae as the valve cusps extend into the atrium during systole, followed by a soft late systolic murmur of mitral regurgitation. The click varies with maneuvers (earlier with decreased left ventricular end-diastolic volume (LVEDV), later with increased LVEDV).
Standing and valsalva decrease preload, reducing the LVEDV and relieving the chordae tendineae of some tension. This makes the click occur earlier in systole.
Squatting increases preload, augmenting the LVEDV and placing greater tension on the chordae tendineae. This makes the click occur later in systole.
Echocardiography is the most useful tool in diagnosing and evaluating MVP. It can determine the degree of prolapse, severity of mitral valve thickening, presence and amount of regurgitation as well as other determinants of cardiac function such as LVEF.
Like any cardiac valvular disease, mitral valve prolapse may predispose to endocarditis, but it is very rare and the current recommendation is against antibiotic prophylaxis.
Asymptomatic patients should be reassured that their condition is benign.
Complications associated with MVP include cardiac arrhythmias (eg, atrial fibrillation, ventricular tachycardia), infective endocarditis, embolic stroke, sudden cardiac death, and worsening MR, leading to decompensated heart failure.
Most patients with MVP have a risk for cardiovascular morbidity and mortality similar to that of the general population, although moderate to severe MR and left ventricular ejection fraction <50% have been noted to increase the risk for adverse cardiac events. Other risk factors for cardiovascular morbidity include left atrial size ≥40 mm, flail mitral leaflet, and age >50.