Mitral Valve Prolapse

Relevant physical signs

• General inspection
  • Young patient
  • Myopathic facies (myotonic dystrophy)
  • Extremely tall patient (Marfan’s syndrome)
• Peripheries
  • Stigmata of infective endocarditis
  • Clubbing
  • Arachnodactyly (Marfan’s syndrome)
  • Pulse
    • May be in atrial fibrillation
    • May be jerky in nature due to mitral regurgitation
  • Blue sclerae (osteogenesis imperfecta)
  • High arched palate (Marfan’s syndrome)
  • Raised jugular venous pulsation with giant v waves (pulmonary hypertension)
• Precordium
  • Palpation
    • Apex beat
      • Displaces inferolaterally as mitral regurgitation gets more severe
      • Acquires a thrusting quality with increasing severity of MR
    • Palpable thrill of mitral regurgitation over the mitral area
    • Right ventricular heave (pulmonary hypertension)
  • Auscultation
    • Soft S1
    • S2 normal or partly-obscured by PSM of MR; loud if consequent pulmonary hypertension
    • S3 present in severe MR – marker of rapid ventricular filling
    • S4 in reduced ventricular compliance, but only if in sinus rhythm
    • Mid-systolic click with late crescendo-decrescendo murmur radiating to the axilla
      • Click is due to snapping of chordae when leaflets bow into the atrium
      • Click is variable – i.e. its timing changes with manoeuvres which change LV volume
      • Standing, Valsalva manoeuvre decrease LV volume, so the opening click is earlier
      • Lying down and squatting increases LV volume, so opening click is later
• Lung bases for pulmonary oedema (left ventricular failure)
• Legs for peripheral oedema (right ventricular failure)
• Pronator drift (embolic disease causing stroke)

Causes of mitral valve prolapse

• Idiopathic, primary mitral valve prolapse
• Familial: autosomal dominant with incomplete penetrance
• Connective tissue disorders
  • Marfan’s syndrome
  • Ehlers-Danlos syndrome
  • Osteogenesis imperfecta
  • Pseudoxanthoma elasticum
  • Systemic lupus erythematosus
• Ischaemic heart disease
• Trauma
• Associated disorders
  • Polycystic kidney disease
  • Myotonic dystrophy

Complications

• Mitral regurgitation
• Thromboembolic disease
• Atrial fibrillation
• Infective endocarditis
• Sudden cardiac death
• Arrhythmias (prolonged QT interval)

Investigations

• Electrocardiogram
  • Atrial fibrillation
  • Prolonged QT interval
  • Left ventricular hypertrophy secondary to mitral regurgitation
  • Dominant R wave in V1 suggesting pulmonary hypertension
• Chest radiograph
  • Cardiomegaly
  • Pulmonary oedema
  • Prominent pulmonary arteries in pulmonary hypertension
• Trans-thoracic echocardiogram
  • Confirm diagnosis and assess severity
  • Look for complications – mitral regurgitation and pulmonary hypertension

Management

• Multidisciplinary team approach
• Patient education and reassurance
• Treat acute episodes of heart failure with diuretics
• Consider β-blockers for control of arrhythmias
• Surgical valve replacement if severe, symptomatic MR (see mitral regurgitation above for indications for valve replacement)

Presentation

Sir, this patient has a mitral valve prolapse which has been complicated by mitral regurgitation which is at least moderate in severity. On examination of the peripheries, there are no stigmata of infective endocarditis. There is no clubbing or cyanosis. The pulse is irregular, but currently rate-controlled. There is no conjunctival pallor. The jugular venous pulsation is not elevated. On examination of the precordium, the apex beat is displaced inferolaterally. There is no palpable right ventricular heave, and there are no palpable thrills. The first heart sound is soft, and the second heart sound is normal in character. There is a mid-systolic click, which is followed by a crescendo-decrescendo murmur which radiates to the axilla and is best heart at the apex in expiration.

There are no signs of an underlying connective tissue disorder such as a high-arched palate or arachnodactyly of Marfan’s syndrome, blue sclerae of osteogenesis imperfecta or myopathic facies to suggest myotonic dystrophy. I would like to examine the abdomen to check for ballotable kidneys, as mitral valve prolapse is known to be associated with polycystic kidney disease.

In summary, this patient has mitral valve prolapse complicated by mitral regurgitation of at least moderate severity and atrial fibrillation.