High-voltage pulsed field ablation: a novel strategy for multiple redo ventricular tachycardia ablation in nonischemic cardiomyopathy patients

Abstract Background Catheter ablation ventricular tachycardia (VT) in non-ischemic cardiomyopathy (NICM) remains particularly challenging, as arrhythmogenic substrates are often deep and heterogeneous within the myocardium. To overcome these limitations, a novel high voltage pulsed field ablation (hv-PFA) system is under investigation. Purpose The aim of our study is to evaluate the safety and feasibility of hv-PFA during VT ablation. Methods This single-center series included consecutive NICM patients undergoing repeat ablation of recurrent monomorphic VT with an 8.5-French force-sensing hv-PFA catheter between July 2024 and August 2025. A scar homogenization approach was used in all patients. Procedural success was defined as absence of residual abnormal electrograms within bipolar voltage area 1.5mV. Devices and mapping systems integrity was monitored during the procedure. Follow-up data were collected during in-office evaluations and device remote monitoring. Results Seven consecutive patients mean age 58±10.4 years; female (1) 14.3% underwent a total of nine procedures, as one patient underwent three ablations for VT recurrence. Mean number of prior procedures was 2.29±1.11. A scar homogenization strategy was applied in all procedures (median number of lesions, 14 IQR8). Procedural success was achieved in all patients. During a mean follow-up of 6 months (193±128 days), arrhythmic recurrence occurred in 2 (28.6%) patients. Electromagnetic interference resulted in defibrillator malfunction in 2 (22.2%) procedures, requiring generator replacement, and mapping-system malfunction in 3 (33.3%) procedures. Conclusion Preliminary findings from this prospective series show efficacy of hv-PFA in NICM patients with prior multiple unsuccessful VT ablation. Further studies are required to define the safety profile of this novel ablation system.