Abstract

Background Persistent atrial fibrillation (AF) remains challenging to treat with catheter ablation. The left atrial posterior wall (PW) may represent an important non-pulmonary vein (PV) substrate; however, randomised trials have not demonstrated improved outcomes with adjunctive PW isolation (PWI), potentially reflecting technical limitations of thermal ablation rather than a lack of mechanistic relevance. Pulsed-field ablation (PFA) is a non-thermal ablation modality that selectively targets myocardial tissue and may enable safer and more consistent PWI. We compared real-world outcomes of PFA and radiofrequency ablation (RFA) for combined PV isolation and PWI in patients with persistent AF. Methods 200 consecutive patients (100 PFA and 100 RFA) undergoing combined PVI and PWI were retrospectively followed for up to 12 months. Baseline characteristics were broadly similar; however, PFA patients had lower left ventricular ejection fraction (LVEF) (43.5% (35.5–55.5%) vs 47% (40–58), p=0.01) and higher CHA₂DS₂-VA risk score (3 (2–4) vs 2 (1–3), p=0.01). Primary outcomes were acute procedural success and freedom from recurrent atrial tachyarrhythmia (AT) at 6 and 12 months. Results PFA achieved near-universal PWI compared with RFA (99% vs RFA: 65%, p<;0.005), with shorter procedure duration (106 vs 143.5 min, p<0.005), reduced left atrial dwell time (62 vs 98 min, p<0.005), and faster time to PVI and PWI (all p<0.005). Major non-vascular complications were uncommon (1.5%) and similar between groups. At 12 months, freedom from recurrent AT was higher with PFA (70% vs RFA 54%, p=0.03), with lower odds of first detected AT recurrence in adjusted time-to-event analysis (OR 0.46 (0.26–0.82), p=0.009). Conclusions In this real-world cohort, PFA was associated with a higher rate of acute PWI and greater freedom from AT compared with RFA, without a signal of increased complications. Prospective randomised studies are needed to define the role of PWI delivered with PFA in patients with persistent AF, including those with reduced LVEF.