Is Mitral Annuloplasty an Effective Treatment for Severe Atrial Functional MR?

Atrial functional mitral regurgitation (MR) is caused by annular dilatation and flattering associated with altered atria/annulus dynamics in patients with severely dilated left atrium and normal leaflets anatomy. Inadequate leaflets adaption is considered a mechanistic culprit as well. Prevalence of at least moderate atrial functional MR varies between 4.7% and 7% in patients with permanent and long standing persistent atrial fibrillation (AF) and is even higher in patients with Heart Failure with preserved Ejection Fraction (HFpEF). Unlike secondary MR in the setting of left ventricular disease, results of surgical treatment of severe atrial functional MR has remained largely unspoken. The aim of this study is to analyze short and mid-term results of isolated annuloplasty in patients with severe, symptomatic atrial functional MR, in comparission to a matched cohort of patients with secondary MR.