Mitral valve prolapse

Mitral valve prolapse is the most common cause of chronic mitral regurgitation in developed countries.

One or both leaflets prolapse into the left atrium during systole.

Diagnosis is established by clinical examination and echocardiogram.

Usually follows a benign course with a favourable prognosis.

Uncommonly, serious complications occur such as infective endocarditis, severe mitral regurgitation, or sudden cardiac death. Patients at increased risk are identifiable by clinical and echocardiographical features.

Mitral valve repair is the preferred treatment option in patients with mitral valve prolapse and severe mitral regurgitation.

Mitral valve prolapse (MVP) is defined as bowing or billowing of one or both mitral valve leaflets into the left atrium during systole.[1]Otto CM, Nishimura RA, Bonow RO, et al. 2020 ACC/AHA guideline for the management of patients with valvular heart disease: a report of the American College of Cardiology/American Heart Association Joint Committee on Clinical Practice Guidelines. Circulation. 2021 Feb 2;143(5):e72-e227. https://www.doi.org/10.1161/CIR.0000000000000923 http://www.ncbi.nlm.nih.gov/pubmed/33332150?tool=bestpractice.com [2]Bonow RO, O'Gara PT, Adams DH, et al. 2020 Focused update of the 2017 ACC expert consensus decision pathway on the management of mitral regurgitation: a report of the American College of Cardiology Solution Set Oversight Committee. J Am Coll Cardiol. 2020 May 5;75(17):2236-70. https://www.doi.org/10.1016/j.jacc.2020.02.005 http://www.ncbi.nlm.nih.gov/pubmed/32068084?tool=bestpractice.com [3]Zoghbi WA, Adams D, Bonow RO, et al. Recommendations for noninvasive evaluation of native valvular regurgitation: a report from the American Society of Echocardiography developed in collaboration with the Society for Cardiovascular Magnetic Resonance. J Am Soc Echocardiogr. 2017 Apr;30(4):303-71. https://www.doi.org/10.1016/j.echo.2017.01.007 http://www.ncbi.nlm.nih.gov/pubmed/28314623?tool=bestpractice.com [4]Freed LA, Benjamin EJ, Levy D, et al. Mitral valve prolapse in the general population: the benign nature of echocardiographic features in the Framingham heart study. J Am Coll Cardiol. 2002 Oct 2;40(7):1298-304. https://www.sciencedirect.com/science/article/pii/S0735109702021617?via%3Dihub http://www.ncbi.nlm.nih.gov/pubmed/12383578?tool=bestpractice.com

MVP with leaflet thickening of 5 mm or greater during diastasis, reflecting myxomatous degeneration, is referred to as classic prolapse and is a predictor of complications.[5]Marks AR, Choong CY, Sanfilippo AJ, et al. Identification of high-risk and low-risk subgroups of patients with mitral-valve prolapse. N Engl J Med. 1989 Apr 20;320(16):1031-6. http://www.ncbi.nlm.nih.gov/pubmed/2927482?tool=bestpractice.com [6]Nishimura RA, McGoon MD, Shub C, et al. Echocardiographically documented mitral valve prolapse: long-term follow-up of 237 patients. N Engl J Med. 1985 Nov 21;313(21):1305-9. http://www.ncbi.nlm.nih.gov/pubmed/4058522?tool=bestpractice.com

The degree of associated mitral regurgitation ranges from none to severe.

The mitral valve and annulus are saddle shaped.[7]Levine RA, Triulzi MO, Harrigan P, et al. The relationship of mitral annular shape to the diagnosis of mitral valve prolapse. Circulation. 1987 Apr;75(4):756-67. http://www.ncbi.nlm.nih.gov/pubmed/3829339?tool=bestpractice.com [8]Levine RA, Stathogiannis E, Newell JB, et al. Reconsideration of echocardiographic standards for mitral valve prolapse: lack of association between leaflet displacement isolated to the apical four chamber view and independent echocardiographic evidence of abnormality. J Am Coll Cardiol. 1988 May;11(5):1010-9. https://www.sciencedirect.com/science/article/pii/S0735109798900596?via%3Dihub http://www.ncbi.nlm.nih.gov/pubmed/3281989?tool=bestpractice.com The echocardiographic definition of MVP is prolapse of leaflet(s) by ≥2 mm above the level of the annulus during systole in the long-axis parasternal view.[3]Zoghbi WA, Adams D, Bonow RO, et al. Recommendations for noninvasive evaluation of native valvular regurgitation: a report from the American Society of Echocardiography developed in collaboration with the Society for Cardiovascular Magnetic Resonance. J Am Soc Echocardiogr. 2017 Apr;30(4):303-71. https://www.doi.org/10.1016/j.echo.2017.01.007 http://www.ncbi.nlm.nih.gov/pubmed/28314623?tool=bestpractice.com [Figure caption and citation for the preceding image starts]: Parasternal long-axis echocardiogram of mitral valve illustrating prolapse of posterior leaflet (red arrow)From the personal collection of Brian Griffin, MD; used with permission [Citation ends].

In other echocardiographical views, such as the apical 4-chamber view, the leaflets may appear to prolapse even though they remain below the level of the entire mitral valve. This can lead, as happened in older studies, to an incorrect diagnosis of MVP.[9]Warth DC, King ME, Cohen JM, et al. Prevalence of mitral valve prolapse in normal children. J Am Coll Cardiol. 1985 May;5(5):1173-7. https://www.sciencedirect.com/science/article/pii/S0735109785800218?via%3Dihub http://www.ncbi.nlm.nih.gov/pubmed/3989128?tool=bestpractice.com [10]Savage DD, Garrison RJ, Devereux RB, et al. Mitral valve prolapse in the general population. 1. Epidemiologic features: the Framingham study. Am Heart J. 1983 Sep;106(3):571-6. http://www.ncbi.nlm.nih.gov/pubmed/6881031?tool=bestpractice.com