Posterior Inter-Antral Linear Ablation Using Pulsed Field Energy: Electrophysiological Validation and Early Clinical...

Durable conduction block across the left atrial roof remains challenging because of complex anatomy and limitations of thermal energy delivery. Pulsed field ablation (PFA) may enable a short posterior inter-antral line as an adjunctive strategy beyond pulmonary vein isolation (PVI), providing linear conduction block at a more inferior posterior LA location than a conventional roofline. However, its electrophysiological characteristics and clinical relevance remain uncertain.

In this single-center, nonrandomized comparative cohort study, a prospectively enrolled cohort undergoing PVI plus posterior inter-antral linear ablation was compared with contemporaneous patients undergoing PVI without additional left atrial ablation. The primary clinical endpoint was atrial arrhythmia recurrence beyond a 90-day blanking period. Propensity score matching was the primary comparative analysis; inverse probability of treatment weighting and multivariable Cox regression were sensitivity analyses. Among 306 patients, 65 underwent posterior inter-antral linear ablation and 241 underwent PVI alone. Posterior-line ablation produced characteristic reciprocal pacing responses and a caudal-to-cranial posterior wall activation pattern consistent with conduction block. During a median follow-up of 198 days, atrial arrhythmia recurrence occurred in 4 of 65 (6.2%) versus 38 of 241 (15.8%) patients. In the primary PSM analysis, posterior inter-antral linear ablation was associated with lower recurrence (HR 0.23; 95% CI 0.07-0.78), with consistent results in sensitivity analyses.

Posterior inter-antral linear ablation using PFA provides a reproducible electrophysiological pattern of conduction block and was associated with lower short-term atrial arrhythmia recurrence than PVI alone in patients with paroxysmal atrial fibrillation. These findings warrant confirmation in randomized trials.