Looking into the Mechanistic Link Between Mitral Regurgitation and Atrial Fibrillation.

Atrial functional mitral regurgitation (AFMR) can occur in patients with atrial fibrillation despite a preserved left ventricular systolic function. AFMR has received attention as a cause of heart failure; it is a therapeutic target in patients with heart failure with atrial fibrillation. Mitral annular dilatation from atrial fibrillation-induced left atrial dilatation is necessary for the generation of AFMR. Posterior mitral leaflet hamstringing also relates to the generation of AFMR. Further mitral annular dilatation owing to progressive left atrial and left ventricular dilatations, with mitral regurgitation-induced volume overload, worsens AFMR.