Mitral Valve Prolapse: A Small Anomaly of the Heart, a Nonspecific Manifestation of Hereditary Connective Tissue Disorders or an Independent Syndrome?

Abstract

The review article presents modern concepts of the mitral valve prolapse. The issues of pathogenesis, diagnostic criteria of primary and probable prolapse are reflected, the issues of epidemiology are considered in detail. The problems associated with significant overdiagnosis of this condition in our country (up to 36.8%) are noted, which is due to ignoring internationally agreed algorithms and incorrect interpretation of the results obtained during echocardiography. When using a parasternal two-chamber position and choosing a diagnostic threshold of 3 mm or more, mitral valve prolapse is detected in 4.3% of practically healthy young people, which is comparable to population-based world studies, in the absence of sex differences. The place of mitral valve prolapse in the algorithms for diagnosing hereditary syndromes - Marfan and Ehlers-Danlos, its pleiotropy, which should be taken into account when stratifying the risk of clinically significant events and in case of probable prolapse, is discussed. The situations that allow to interpret mitral valve prolapse as an independent hereditary syndrome or a small anomaly of the heart are indicated. The article presents current views on the pathogenesis of mitral valve prolapse, the role of transforming growth factor-β in the progression of myxomatous degeneration of the valves, the development of manifestations of cardiomyopathy. The prognostic value of primary prolapse in its natural course is shown - the progression of myxomatosis of the valves, mitral insufficiency, dilation of the main vessels.