Faculty Opinions recommendation of Evidence of atrial functional mitral regurgitation due to atrial fibrillation: reversal with arrhythmia control.

OBJECTIVES: The purpose of this study was to determine whether atrial fibrillation (AF) might cause significant mitral regurgitation (MR), and to see whether this MR improves with restoration of sinus rhythm.BACKGROUND: MR can be classified by leaflet pathology (organic/primary and functional/secondary) and by leaflet motion (normal, excessive, restrictive). The existence of secondary, normal leaflet motion MR remains controversial.METHODS: We performed a retrospective cohort study. Patients undergoing first AF ablation at our institution (n = 828) were screened. Included patients had echocardiograms at the time of ablation and at 1-year clinical follow-up. The MR cohort (n = 53) had at least moderate MR. A reference cohort (n = 53) was randomly selected from those patients (n = 660) with mild or less MR. Baseline echocardiographic and clinical characteristics were compared, and the effect of restoration of sinus rhythm was assessed by follow-up echocardiograms.RESULTS: MR patients were older than controls and more often had persistent AF (62% vs. 23%, p < 0.0001). MR patients had larger left atria (volume index: 32 cm(3)/m(2) vs. 26 cm(3)/m(2), p = 0.008) and annular size (3.49 cm vs. 3.23 cm, p = 0.001), but similar left ventricular size and ejection fraction. Annular size, age and persistent AF were independently associated with MR. On follow-up echocardiogram, patients in continuous sinus rhythm had greater reductions in left atrial size and annular dimension, and lower rates of significant MR (24% vs. 82%, p = 0.005) compared with those in whom sinus rhythm was not restored.CONCLUSIONS: AF can result in "atrial functional MR" that improves if sinus rhythm is restored.Copyright © 2011 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved. PMID: 21939832