Mitral Valve Prolapse

Excerpt

Mitral valve prolapse (MVP) is a valvular heart disease disorder in which thickened mitral leaflets protrude into the left atrium during systole by at least 2 mm systolic displacement of the mitral leaflet above the annular plane, best assessed in parasternal long-axis views because other views may overcall prolapse (see Image. Mitral Valve Prolapse). MVP is also known in the medical literature as floppy mitral valve syndrome, systolic click-murmur syndrome, and billowing mitral leaflets. In the general population, the estimated prevalence of MVP is about 2% to 3%, with a slightly higher prevalence in women. Overall, MVP affects about 160 million globally.

Most patients with MVP remain asymptomatic and have a near-normal life expectancy. MVP is the most common cause of nonischemic mitral valve regurgitation in the United States. A small proportion of those affected by MVP progress to severe mitral valve regurgitation. Even in the absence of mitral valve regurgitation, a small subset of those with MVP may develop infective endocarditis or life-threatening ventricular arrhythmias leading to sudden cardiac death (SCD). Advances in understanding MVP have identified arrhythmic mitral valve prolapse (AMVP), a distinct high-risk phenotype that occurs independently of mitral valve regurgitation. Current understanding suggests that AMVP may occur independently of mitral valve regurgitation severity and may relate to mechanical traction on papillary muscles and adjacent myocardium, promoting fibrosis and ventricular ectopy.

The identification of mitral annular disjunction (MAD) and its association with ventricular arrhythmias has further improved our understanding of MVP. An MVP is usually identified on clinical examination by cardiac auscultation and confirmed by transthoracic echocardiography. Guidelines for risk stratification and management have streamlined care for patients with MVP. The definitive management of symptomatic MVP includes conservative approaches, but may also involve consideration of mitral valve repair. Especially in the presence of decompensated heart failure or cardiogenic shock.