Pulsed-Field Ablation for Recurrent Atypical Atrial Flutter

Recurrent atypical atrial flutter (AFL) after prior atrial fibrillation or flutter ablation remains challenging to treat, and conventional radiofrequency ablation may be limited by incomplete lesion formation and risk of collateral damage. Pulsed-field ablation (PFA) uses non-thermal electric fields to create myocardial lesions with relative sparing of surrounding tissues and may improve the safety and efficacy of ablation for atypical AFL. This prospective, non-randomized, single-arm study will enroll approximately 30 patients with clinically documented recurrent atypical AFL who are referred for elective catheter ablation using a point-by-point pulsed-field ablation system. During the index procedure, detailed electroanatomic mapping will be performed to identify the critical isthmus or circuit, followed by linear or focal PFA and confirmation of bidirectional conduction block. The primary safety endpoint is the incidence of procedure- and device-related primary adverse events. The primary effectiveness endpoint is acute procedural success, defined as termination of atypical AFL and establishment of bidirectional block across the targeted lesion set at the end of the procedure. Secondary endpoints include recurrence of any atrial arrhythmia during 12-month follow-up, durability of the linear lesions assessed by repeat electroanatomic mapping at 3 months, changes in atrial scar on cardiac MRI, peri-procedural changes in blood biomarkers, and the rate of serious adverse events related to the procedure or study device.