Efficacy and limitation of nonparoxysmal atrial fibrillation ablation in patients with heart failure with preserved ejection fraction

Introduction: Catheter ablation for atrial fibrillation (AF) reduces heart failure (HF) hospitalization in patients with HF with preserved ejection fraction (HFpEF). However, the long-term outcomes and subclinical HF after nonparoxysmal AF ablation in HFpEF patients have not been fully evaluated.

Methods and results: One-hundred-ninety nonparoxysmal AF patients with left ventricular ejection fraction ≥50% who underwent first-time AF ablation were studied. HFpEF was diagnosed from a history of congestive HF and/or combined criteria of N-terminal pro-brain natriuretic peptide (NT-proBNP) concentration and transthoracic echocardiogram parameters, including average septal-lateral E/e' and tricuspid regurgitation peak velocity. Ninety-five patients with HFpEF (HFpEF group) were compared with 95 patients without HF (CNT group). Low voltage area (LVA) was defined as an area with a bipolar electrogram of <0.5 mV covering >5% of the total left atrial surface. The primary endpoint was a composite of death from any cause or hospitalization for worsening HF. The secondary endpoint was subclinical HFpEF defined from NT-proBNP concentration and average septal-lateral E/e' or tricuspid regurgitation peak velocity at 6-12 months after the procedure irrespective of the rhythm. Kaplan-Meier curves showed that the primary composite endpoint did not differ between the two groups (mean follow-up period 707 ± 75 days, log-rank p = 0.5330). However, significantly more patients in the HFpEF group reached the secondary endpoint (42 [44%] vs. 13 [14%], p < 0.0001). Multivariate analysis revealed that a high preablation NT-proBNP (odds ratio [OR] 1.001, 95% confidence interval [CI] 1.001-1.002, p = 0.0040) and the existence of LVA (OR 5.983, 95% CI 1.463-31.768, p = 0.0194) independently predicted the secondary endpoint in HFpEF patients.

Conclusion: After nonparoxysmal AF ablation, mortality of HFpEF patients was not inferior compared to patients without coexisting HF. However, subclinical HF occasionally persisted especially in HFpEF patients with a high preprocedure NT-proBNP concentration and LVA.