High-Voltage Pulsed Field Ablation

BACKGROUND: Catheter ablation of ventricular tachycardia (VT) in nonischemic 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. OBJECTIVES: The aim of our study was 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-F 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 noninducibility of any VT and absence of residual abnormal electrograms within bipolar voltage area <1.5 mV. Device and mapping system integrity was monitored during the procedure. Follow-up data were collected during in-office evaluations and remote device monitoring. RESULTS: Seven consecutive patients (mean age 58 ± 10.4 years; 1 female [14.3%]) underwent a total of 9 procedures, as 1 patient underwent 3 ablations for VT recurrence. The mean number of prior procedures was 2.29 ± 1.11. A scar homogenization strategy was applied in all procedures (median 14 lesions [Q1-Q3: 9-17 lesions]). Procedural success was achieved in all patients. During a median follow-up of 10 months (320 days [Q1-Q3: 183-407 days]), arrhythmic recurrence occurred after 3 (33.3%) of 9 procedures in 2 (28.6%) of 7 patients. Electromagnetic interference resulted in defibrillator malfunction in 2 (22.2%) procedures, requiring generator replacement, and mapping system malfunction in 3 (33.3%) procedures. CONCLUSIONS: Preliminary findings from this prospective series show efficacy of hv-PFA in NICM patients with prior multiple unsuccessful VT ablations. Further studies are required to define the safety profile of this novel ablation system.