Mitral valve prolapse

Bulging (prolapse) of one or both mitral valve leaflets into the left atrium during systole, due to degeneration of valve tissue (myxomatous change). Often causes a characteristic mid-systolic click with or without a late systolic murmur, and can lead to mitral regurgitation.

• Common valvular disorder (~2% of people) and the leading cause of non-ischemic mitral regurgitation. Usually benign, but can sometimes result in severe MR with heart failure, arrhythmias (rarely sudden death), infective endocarditis, or stroke. A classic exam topic due to its distinctive auscultation findings (click-murmur) and associations (e.g. Marfan syndrome).

• Often asymptomatic: many cases are found incidentally during a routine exam (hearing a click/murmur) or via echocardiogram.
• Common scenario: a young female patient with palpitations, atypical chest pain (non-exertional), or anxiety; on exam she has a mid-systolic click followed by a late systolic murmur at the apex.
• Associated with connective tissue diseases: patients with Marfan or Ehlers-Danlos (tall, thin habitus, hyperflexible joints, maybe pectus excavatum) often have MVP due to myxomatous valve changes.
• If severe mitral regurgitation develops, patients can present with dyspnea, fatigue, or arrhythmias later in life. Exam then shows a holosystolic murmur (from MR) that can obscure the click.

1. Suspected MVP (hearing a click/murmur) is confirmed by echocardiography, which shows leaflet displacement (>2 mm beyond annulus) and can quantify mitral regurgitation.
2. Know the maneuvers: standing/Valsalva (↓ venous return) make the click occur earlier and murmur longer, whereas squatting/handgrip (↑ afterload/volume) delay the click and shorten the murmur. This helps distinguish MVP’s murmur from others (e.g. differentiating it from hypertrophic cardiomyopathy).
3. If the patient has palpitations or syncope, evaluate for arrhythmias. MVP can cause ventricular ectopic beats or arrhythmias in some patients (Holter monitoring or ECG may show PVCs, etc.).
4. No antibiotic prophylaxis is needed for MVP (for dental or minor procedures) unless the patient has a history of infective endocarditis or valve repair.
5. Don’t confuse MVP’s mid-systolic click with an aortic ejection click (e.g., bicuspid aortic valve): the latter occurs earlier (right after S1), at the base of the heart, and does not change with position.

1. If asymptomatic and trivial regurgitation: reassurance and observation (no treatment needed).
2. For autonomic symptoms (palpitations, chest pain, anxiety): beta blockers (e.g. propranolol) can help alleviate symptoms.
3. When severe MR is present (especially with symptoms or LV dysfunction): recommend mitral valve repair (surgery) before heart failure ensues.
4. Manage arrhythmias if they occur (e.g., treat atrial fibrillation with rate control and anticoagulation as appropriate).
5. No need for antibiotic prophylaxis for MVP (unless there’s a prosthetic valve or prior endocarditis).

• The hallmark mid-systolic click is practically diagnostic of MVP.
• MVP murmur moves with maneuvers: it gets longer/louder when standing, and shorter/softer when squatting (due to LV volume changes).
• Common in young women — historically called Barlow syndrome; these patients often have palpitations or anxiety but a benign prognosis.
• Associations: think connective tissue – conditions like Marfan and Ehlers-Danlos often feature MVP (myxomatous valves).
• Most common cause of MR in patients without coronary heart disease (MVP causes degenerative mitral regurgitation).
• Exam update: no prophylactic antibiotics needed for MVP (unless there’s a prosthetic valve or prior endocarditis).

• Acute chordae rupture: sudden chest pain, pulmonary edema, and cardiogenic shock in an MVP patient could indicate a ruptured chordae tendineae causing acute severe MR (flail leaflet) – a surgical emergency.
• Unexplained syncope or complex ventricular arrhythmias (PVCs, VT) in MVP – could signify malignant arrhythmic MVP with risk of sudden death; requires urgent cardiology evaluation.
• Heart failure signs (new dyspnea, edema) or LV dilation on echo in an MVP patient – suggests progression to severe chronic MR; consider timely valve repair to prevent permanent damage.

1. Auscultation suggests MVP (click ± murmur) → obtain a transthoracic echocardiogram to confirm prolapse and assess degree of MR.
2. If MVP is confirmed with no significant MR and no symptoms → periodic follow-up (e.g., exam and echo every few years).
3. If symptomatic (palpitations, chest pain) but no severe MR → conservative management (reassurance, lifestyle, ± beta blockers) and evaluate/treat other causes of symptoms.
4. If severe MR or LV dysfunction on echo (even if asymptomatic) → refer for mitral valve repair (surgical intervention) before onset of heart failure symptoms.
5. In all cases, address complications: e.g., manage atrial fibrillation (anticoagulate if needed), and remember no endocarditis prophylaxis is required for uncomplicated MVP.

• Young woman with anxiety, palpitations, and atypical chest pain; exam reveals a mid-systolic click and late systolic murmur that becomes softer when squatting → Mitral valve prolapse.
• Tall, thin patient with long limbs and hyperflexible joints (Marfanoid habitus), plus a mid-systolic click on auscultation → Mitral valve prolapse (associated with connective tissue disorder).
• Older patient with history of MVP who now has exertional dyspnea and a new holosystolic murmur radiating to the axilla → Severe mitral regurgitation due to progressed MVP.