Focal pulsed field ablation in complex atrial tachycardia: First clinical experience and 1-year outcome

BACKGROUND: Pulsed field ablation (PFA) has become increasingly important in the treatment of cardiac arrhythmias. In addition to single-shot devices mainly used for pulmonary vein isolation, focal PFA may provide a treatment option that increases the versatility of the technique. OBJECTIVE: The purpose of this study was to provide data on feasibility, safety, and long-term outcome of focal PFA for ablation of complex atrial tachycardia (AT). METHODS: All consecutive patients (n = 34) with complex AT treated at our department between 2022 and 2023 with a focal PFA system (CENTAURI™, Galvanize Therapeutics) were included. The majority of patients (32/34) previously had undergone at least 1 radiofrequency ablation. Established contact force-sensing catheters were used for PFA application in combination with a PFA generator. Pulsed electric field trains were conducted in a R-wave triggered manner. RESULTS: Acute procedural success was accomplished in all patients. PFA included creation of 51 linear lesions and (re)isolation of 12 pulmonary veins. Mean procedural duration was 102.7 ± 30.3 minutes, with left atrial dwell time of 75.0 ± 24.7 minutes. Mean fluoroscopy duration was 8.7 ± 5.3 minutes. No complications occurred. After mean follow-up of 340.9 ± 130.1 days, recurrence of any AT occurred in 15 patients (44.1%). During 9 reablations, 3 gaps in previously created linear lesions were detected; the majority of recurrences (n = 6) were not related to previous PFA lesion creation. CONCLUSION: Focal PFA of complex AT substrates was safe and efficient. Acute procedural success was 100%. After 1 year, the majority of patients were in sinus rhythm. A minority of recurrences was caused by insufficient PFA lesion creation.