Cardiovascular Disease· Topic 2.6 Valvular heart disease and cardiac murmurs· 2.6.5

Mitral valve prolapse

Mitral valve prolapse is systolic displacement of one or both mitral leaflets into the left atrium, usually from myxomatous degeneration, marked by a mid-systolic click and a late systolic murmur. Most cases are benign, but it is the leading cause of primary mitral regurgitation and a small subset carry arrhythmic risk. Management is reassurance for benign disease, beta-blockers for symptoms, and mitral valve repair for severe regurgitation.

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What this article covers

  • Overview

    Definition: mitral valve prolapse is systolic billowing of one or both mitral leaflets more than 2 mm above the annular plane into the left atrium, usually from myxomatous degeneration.

  • Epidemiology

    Common, the leading cause of primary mitral regurgitation requiring surgery.

  • Risk factors

    Myxomatous degeneration and familial predisposition.

  • Pathophysiology

    Myxomatous leaflets and elongated chordae: redundant tissue allows systolic prolapse into the atrium.

  • Clinical features

    Usually asymptomatic. A mid-systolic click followed by a late systolic murmur at the apex, with the click moving earlier on standing or Valsalva.

  • Differential diagnosis

    Mitral regurgitation of other cause: holosystolic rather than late systolic (Mitral regurgitation).

  • Diagnosis

    Establish with echocardiography showing systolic leaflet displacement above the annular plane: the diagnostic basis is transthoracic echocardiography demonstrating prolapse of one or both leaflets…

  • Management

    First-line, reassure and observe most patients: benign prolapse without significant regurgitation needs only explanation and periodic follow-up.

  • Complications

    Progressive severe mitral regurgitation and chordal rupture.

  • Prognosis

    Benign in the majority. Higher morbidity in those who develop severe mitral regurgitation.

  • Prevention

    Surveillance echocardiography every 1 to 3 years depending on regurgitation severity to detect progression.

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