Heart failure with preserved ejection fraction in atrial functional mitral regurgitation - Insight from the REVEAL-AFMR.

Background: Atrial functional mitral regurgitation (AFMR) and heart failure with a preserved ejection fraction (HFpEF) often coexist. However, the clinical impact of HFpEF in patients with AFMR has not been well characterized. This study aimed to determine clinical outcomes and response to mitral valve (MV) intervention or rhythm control therapy in patients with HFpEF and moderate AFMR (HFpEF-AFMR).

Methods: This was a post-hoc analysis of the REVEAL-AFMR, a retrospective observational study involving patients with ≥ moderate AFMR. After excluding patients with severe MR, the presence of HFpEF was defined by the Universal definition.

Results: Of 438 patients with moderate AFMR, 352 met the criteria of HFpEF (prevalence: 80 %). Compared to non-HFpEF-AFMR (n = 86), patients with HFpEF-AFMR were older and had greater symptom burden and a higher prevalence of severe tricuspid regurgitation (19 %). During a median follow-up of 33.2 months, a composite outcome of all-cause mortality or HF hospitalization occurred in 130 patients. Patients with HFpEF-AFMR had a 3.6-fold increased risk of the composite outcome compared to non-HFpEF-AFMR. While MV intervention was not associated with outcomes in HFpEF-AFMR, concomitant tricuspid valve (TV) procedures were associated with a better outcome than isolated MV intervention (HR 0.15, 95 %CI 0.04-0.54, p = 0.009). Catheter or surgical rhythm control showed a favorable outcome in HFpEF-AFMR and atrial fibrillation (HR 0.38, 95 %CI 0.17-0.87, p = 0.008).

Conclusion: HFpEF was substantially common in moderate AFMR and was associated with worse clinical outcomes. Simultaneous MV and TV intervention procedures or rhythm control therapy were associated with better clinical outcomes in HFpEF-AFMR.