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 increasing the versatility of the technique. Objective The study objective was to provide data on feasibility, safety and long-term outcome of focal PFA for the 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, San Carlos, USA) were included. The majority of patients (32/34 pts) had undergone at least one prior radiofrequency ablation. Established contact-force sensing catheters were used for PFA application in combination with a PFA generator. Pulse electric field (PEF) 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 procedure duration was 102.7 ± 30.3 min, with a LA dwell time of 75.0 ± 24.7 min. Mean fluoroscopy duration was 8.7 ± 5.3 min. No complications occurred. After a 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 whereas the majority of recurrences (n=6) was not related to previous PFA lesion creation. Conclusion Focal pulsed-field ablation of complex AT substrates was safe and efficient. Acute procedural success was 100%; after one year, the majority of patients were in sinus rhythm. A minority of recurrences was caused by insufficient PFA lesion creation.