• Clinical science

Mitral valve prolapse

Abstract

Mitral valve prolapse (MVP) is caused by a structural defect of the mitral valve that results in mitral leaflets bulging into the left atrium during systole. In the US, MVP is the most common heart valve abnormality and the most common cause of mitral regurgitation (MR). Although MVP is typically asymptomatic, symptoms (eg., palpitations, fatigue, dyspnea) may arise, especially if associated with MR. A mitral prolapse click is a classic auscultatory finding MVP and diagnosis is made with echocardiography. No specific treatment is needed unless severe, symptomatic MR is present, in which case mitral valve repair or replacement is required.

Epidemiology

  • Prevalance: 2–3% (one of the most common valvular abnormalities in the US)
  • The most common cause of mitral regurgitation in developed countries

References:[1]

Epidemiological data refers to the US, unless otherwise specified.

Etiology

Pathophysiology

Clinical features

  • Most patients are asymptomatic.
  • Rarely: atypical chest pain and anxiety
  • In case of complications: fatigue, dyspnea, syncope, and palpitations (see “Complications” below)
  • Auscultatory findings
    • Mitral valve prolapse click: high-frequency, midsystolic click that is best heard at the mitral region
    • High-frequency, mid-to-late systolic murmur that is best heard at the mitral region and may radiate to the axilla.
    • Patients with severe MR: S3 may be heard as a result of left ventricular overload (especially in the left decubitus position)

References:[2]

Diagnostics

  • ECG: mostly normal
    • A right axis deviation along with T-wave inversions and/or biphasic T waves may be seen in inferior leads (leads II, III and aVF) as a result of right ventricular ischemia.
  • Transthoracic echocardiography (test of choice) to confirm diagnosis
    • Echocardiographic definition of MVP: displacement of the mitral valve during systole by more than 2 mm above the mitral valve annulus in the parasternal long-axis view
      • Classical MVP (∼ 60%): leaflet thickness ≥ 5 mm
      • Non-classical MVP (∼ 40%): leaflet thickness < 5 mm
  • Transesophageal echocardiography (TEE) is used as an adjunct to TTE and intraoperatively to guide mitral valve repair procedures.

Treatment

Complications

We list the most important complications. The selection is not exhaustive.

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  • Jelani Q. Mitral Valve Prolapse. In: Lange RA. Mitral Valve Prolapse. New York, NY: WebMD. https://emedicine.medscape.com/article/155494. Updated November 16, 2016. Accessed April 11, 2018.
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  • Basso C, Perazzolo Marra M, Rizzo S, et al. Arrhythmic mitral valve prolapse and sudden cardiac death. Circulation. 2015; 132(7): pp. 556–566. doi: 10.1161/circulationaha.115.016291.
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last updated 12/06/2018
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