Archief Roodbont

Functional mitral regurgitation (MR) with normal leaflet motion is typically caused by annular dilation associated with left ventricular (LV) enlargement. In the present study, investigators postulated that normal-leaflet-motion MR can also result from annular dilation associated with atrial fibrillation (AF), a condition they termed "atrial functional MR." They retrospectively screened 828 patients undergoing first AF ablation to identify 53 (6.4%) with moderate or greater MR and normal leaflet motion. All patients had LV ejection fractions 50%.

Compared with a randomly selected reference cohort with mild or no MR, subjects were older and more likely to have persistent AF and hypertension. Of the patient characteristics included in multivariate analysis, large mitral annular dimension was associated with the largest odds ratio for MR (8.39). Thirty-two subjects underwent 1-year echocardiographic follow-up. Compared with patients with recurrent AF, those in sinus rhythm had significantly less MR (mean MR jet-to-left-atrial [LA] ratio, 0.16 vs. 0.28) and a significantly smaller mean LA volume index (24 cc³/m² vs. 31 cc³/m²), as well as a smaller mean annular dimension (3.2 cm vs. 3.5 cm; P=0.06).

Comment: This is the largest study to date to demonstrate an association between atrial fibrillation and secondary, normal-leaflet-motion mitral regurgitation and the first to demonstrate early resolution of MR with restoration of sinus rhythm by ablation, suggesting a causal relationship. If these findings are confirmed in a prospective study, a strategy of rhythm control may be preferable to one of rate control in these patients.

— Howard C. Herrmann, MD

Published in Journal Watch Cardiology October 12, 2011