Efficacy of Peak Frequency in Pulmonary Vein Isolation Using Pulsed Field Ablation for Atrial Fibrillation.

INTRODUCTION: Catheter ablation technology for atrial fibrillation (AF) has been improving annually, and pulsed field ablation (PFA) has recently become possible. The optimal protocol has yet to be elucidated, and considering variables, including catheter contact force, is essential for conducting more effective and safer ablation. This study was conducted using peak frequency (PF) mapping to analyze the catheter tip electrode frequency during PFA under the hypothesis that higher PF shows stronger myocardial contact and yields a more pronounced electrical current effect. METHODS: Between December 2024 and April 2025, 12 consecutive patients who underwent PFA for paroxysmal AF using the FARAPULSE system at our hospital were included in this study. Overall, 180 applications were analyzed. The PF before energy delivery was analyzed in the group in which the tip electrode potential disappeared following the first energy delivery using the flower-type configuration. RESULTS: The PF of the distal electrode in the group with potential disappearance following the first delivery was significantly higher than it was in the group without disappearance (291 ± 88 Hz vs. 267 ± 70 Hz, p = 0.02). When the potential at the tip electrode ranged from 0.5 to 1.5 mV, the area under the curve was 0.73. At a cutoff value of 261 Hz for peak frequency, sensitivity reached 67%, and specificity reached 60%. CONCLUSION: Effective PFA may be achieved using the frequency of the catheter tip electrode as an index. Delivering energy to myocardial regions with higher PF may yield greater ablation efficacy.