Mitral Valve Prolapse
-condition where the two flaps of the mitral valve prolapsed do not close smoothly or evenly. When the heart contracts, one or both flaps collapse back into left atrium leading to regurgitation and a potential murmur.
-most common cause of MVP is myxomatous change. Excess connective tissue that thickens the spongiosa and separates collagen bundles in the fibrosa. This is due excess glycosaminoglycans called dermatan sulfate.
-Increased risk in rheumatic fever, Ehler-Danlos syndrome, Marfan syndrome, polycystic kidney disease, and chest wall deformities such as pectus excavatum.
-Rheumatic fever damages the heart valves via repeated inflammation with fibrinous resolution.
Signs and symptoms
-most patients are asymptomatic
-symptomatic patients related to autonomic dysfunction, progression to mitral regurgitation, and associated complications
-symptoms related to progression to mitral regurgitation include fatigue, dyspnea, exercise intolerance, PND, orthopnea, CHF
-symptoms related to autonomic dysftn include atypical chest pain, orthostasis, syncope, and neuropsychiatric symptoms.
-symptoms related to associated complications include stroke, endocarditis, or arrythmia
-mid-systolic click followed by a late systolic murmur heard at the apex.
-Murmur is accentuated by standing and valsalva . This leads to decreased venous return to the heart, thereby decreasing diastolic filling and causing more laxity to the chordate tendinae. This allows mitral valve to prolapsed earlier in systole, leading to earlier systolic click and longer murmur
– Murmur is decreased with squatting.
-asymptomatic patients often require no treatment
-patients with palpitations and chest pain may benefit from beta-blockers
-patients with a hx of stroke or a-fib may require blood thinners such as aspirin or warfarin
-if associated with severe mitral regurgitation, surgical mitral valve repair or replacement may be necessary. Repair preferred to replacement. Current American Heart Association guidelines promote repair of mitral valve in patients before symptoms of heart failure develope