From the Guidelines
Yes, Mitral Regurgitation (MR) can lead to Atrial Fibrillation (AF).
Rationale
- The development of AF is a known complication of MR, particularly in patients with MR due to Mitral Valve Prolapse (MVP) 1.
- The association between MR and AF is attributed to the increased risk of cardiac death or heart failure, with preoperative AF being a predictor of reduced long-term survival after Mitral Valve (MV) surgery for chronic MR 1.
- The persistence of AF after MV surgery can also lead to thromboembolism, necessitating anticoagulation and partially negating the benefits of mitral repair 1.
- The American College of Cardiology/American Heart Association guidelines highlight the importance of considering the risk of AF in patients with MR, particularly when evaluating treatment options and predicting outcomes 1.
From the Research
Relationship Between Mitral Regurgitation and Atrial Fibrillation
- Mitral regurgitation (MR) can lead to left atrium (LA) enlargement, which can subsequently cause atrial fibrillation (AF) 2.
- The presence of MR may increase recurrence rates after AF ablation, with LA size being an independent predictor of AF recurrence 2.
- Atrial functional mitral regurgitation (AFMR) can occur in patients with AF despite preserved left ventricular systolic function, and is characterized by mitral annular dilatation and posterior leaflet hamstringing 3, 4.
- The grading of functional MR in patients with AF and preserved left ventricular ejection fraction depends on both LA dimension and left ventricular systolic dimension, as well as mitral annular dilatation and posterior leaflet hamstringing 5.
Impact of Atrial Fibrillation on Mitral Regurgitation
- AF can induce functional MR despite preserved left ventricular ejection fraction, with significant MR more frequently seen in patients with AF duration of >10 years 5.
- The presence of AF is associated with poor prognosis in patients with acute decompensated heart failure and mild to moderate MR, but not in those without MR 6.
- Mitral regurgitation is associated with increased AF recurrence after AF ablation, but its impact is mediated by LA size 2.
Mechanisms Underlying the Relationship
- Mitral annular dilatation from AF-induced LA dilatation is necessary for the generation of AFMR 4.
- Posterior mitral leaflet hamstringing also relates to the generation of AFMR, with further mitral annular dilatation worsening AFMR 4.
- LA dilatation is a key factor in the development of functional MR in patients with AF, with significant MR not seen in patients without LA dilatations 5.