Pulsed-field vs radiofrequency ablation for posterior wall isolation in persistent atrial fibrillation: A propensity-matched outcome analysis.

BACKGROUND

Left atrial posterior wall isolation (LAPWI) is increasingly used as an adjunct to pulmonary vein isolation in patients with persistent atrial fibrillation (PerAF) despite the absence of strong evidence, but the optimal ablation modality remains uncertain.

OBJECTIVE

Our study focuses on procedural differences between pulsed-field ablation (PFA) and radiofrequency (RF) ablation when LAPWI is performed, rather than on the efficacy of LAPWI itself. PFA may offer advantages over RF ablation owing to its nonthermal mechanism and improved tissue selectivity.

METHODS

In this single-center study, 92 patients with PerAF and posterior low-voltage substrate identified using high-density mapping were treated with either PFA (n = 46) or RF ablation (n = 46) for pulmonary vein isolation plus LAPWI. Remapping was performed to confirm complete electrical isolation. Groups were 1:1 propensity score matched for analysis.

RESULTS

The primary end point was freedom from any sustained atrial arrhythmia (>30 seconds) at 12-month follow-up, assessed using structured Holter electrocardiogram monitoring at 3, 6, and 12 months. Complete LAPWI was achieved in 100% of PFA and 95.7% of RF ablation patients. Procedure time was significantly shorter with PFA (68.2 minutes [44-91] vs 86.8 minutes [58-118]; P < .05). Arrhythmia-free survival at 12 months was similar between groups (58.7% vs 52.2%; P = .57; relative risk 1.13; 95% confidence interval 0.78-1.63). Multivariable Cox regression identified LA diameter, body mass index of >30 kg/m2, and hypertension as independent predictors of arrhythmia recurrence. Complication rates were low and comparable.

CONCLUSION

In patients with PerAF and posterior low-voltage substrate, PFA and RF ablation yielded similar arrhythmia-free survival at 1 year. PFA was associated with shorter procedure times and high rates of posterior wall isolation.