Following first-time atrial fibrillation ablation with a pentaspline pulsed field ablation catheter, the incidence of repeat ablation for atrial tachycardia was low at 1.8%.
Observational (n=236)
What are the mechanisms and anatomical substrates of atrial tachycardia occurring after pulsed field ablation for atrial fibrillation?
Post-PFA atrial tachycardia has a low incidence (1.8%), is predominantly driven by dual-loop left atrial re-entry, and can be successfully treated by targeting critical boundaries.
BACKGROUND: Understanding the mechanisms and anatomical substrates underlying postablation atrial tachycardia (AT) is essential for guiding targeted mapping and successful re-ablation strategies. OBJECTIVE: This study analyzed patients referred for repeat ablation for AT after first-time atrial fibrillation ablation with a pentaspline pulsed field ablation (PFA) catheter. METHODS: High-density electroanatomical mapping was performed to identify the mechanism of post-PFA ATs and assess lesion durability. Re-entrant circuits were analyzed according to the principles of topology (paired rotations, identification of critical boundaries, and ablation strategies). RESULTS: Among 4,144 patients, 236 underwent repeat ablation (160 for atrial fibrillation 3.9% and 76 for AT 1.8%), and this constituted the final cohort. A total of 87 ATs were mapped: 21 in the right atrium (4 focal and 17 peri-tricuspid valve re-entry) and 66 in the left atrium (1 focal and 65 re-entry). Pulmonary vein and posterior wall isolation durability were 84% and 89%, respectively. Left atrial (LA) re-entry mechanisms comprised single-loop (n = 9) and predominantly dual-loop (n = 56) re-entry, including circuits defined by anatomical boundaries (n = 32) or involving an anterior scar (n = 24). In all cases of LA re-entrant AT, sinus rhythm was restored when ablation connected the 2 critical boundaries. Topological principles accurately explained the observed activation patterns and responses to ablation. CONCLUSIONS: The incidence of repeat ablation for AT after pentaspline PFA was low, likely reflecting the high durability of the index lesion sets. Most post-PFA ATs manifested as dual-loop LA re-entry. Retrospective application of the topological framework provided coherent mechanistic interpretations of AT behavior and accurately predicted the response to direct and indirect critical boundary-targeted ablation.
This large registry study provides important insights into the low incidence and mechanisms of atrial tachycardia following pulsed field ablation for atrial fibrillation.
Nakasone et al. (Mon,) conducted a observational in Atrial tachycardia after atrial fibrillation ablation (n=236). Pentaspline pulsed field ablation (PFA) was evaluated on Incidence of repeat ablation for atrial tachycardia. Following first-time atrial fibrillation ablation with a pentaspline pulsed field ablation catheter, the incidence of repeat ablation for atrial tachycardia was low at 1.8%.