His-bundle pacing vs biventricular pacing following atrioventricular nodal ablation in patients with atrial fibrillation and reduced ejection fraction: A multicenter, randomized, crossover study—The ALTERNATIVE-AF trial

Abstract

Background

Atrioventricular node ablation (AVNA) combined with biventricular pacing (BVP) improves outcomes in patients with persistent AF, adequate rate control and reduced left ventricular ejection fraction (LVEF). His bundle pacing (HBP) delivers physiological ventricular activation and is a promising alternative to BVP.

Objective

In this trial we compared HBP with BVP following AVNA.

Methods

In this multicenter, prospective, randomized crossover trial, we recruited patients with persistent AF and reduced LVEF (≤ 40%). All patients underwent AVNA and received both HBP and BVP. Patients were randomized to either HBP or BVP for 9 months (phase 1) after which they were switched to the alternative pacing modality for next 9 months (phase 2). The primary endpoint was change in LVEF.

Results

Fifty patients (64.3±10.3 years, ventricular rate 93.1±19.9 bpm, 72% male) were enrolled. Thirty-eight patients completed the two phases and were included in the crossover analysis. We observed a significant improvement in LVEF with HBP compared to BVP (In phase 1, ΔLVEF_HBP 21.3% and ΔLVEF_BVP 16.7%; In phase 2 ΔLVEF_HBP 3.5% and ΔLVEF_BVP -2.4%; P_{generalized additive model}=0.015). Significant improvements in left ventricular end-diastolic diameter, NYHA class and B-type natriuretic peptide were observed with both pacing modalities when compared with baseline whereas no significant differences were observed between HBP and BVP.

Conclusion

HBP delivers a modest but significant improvement in LVEF in patients with persistent AF, impaired ventricular function and narrow QRS duration post AVNA compared with BVP. Larger long-term trials are required to confirm the additional improvements in function with HBP.