Combined pulsed field and radiofrequency ablation for ventricular tachycardia ablation: a safety, efficacy and comparative study

Background/Introduction Despite the advancement of various ablation techniques and mapping strategies, the outcome of catheter ablation for ventricular tachycardia(VT) remains suboptimal. The long term efficacy of catheter ablation using radiofrequency(RFA) is limited by the depth and durability of lesions. Recently the use of pulsed field ablation (PFA) has been extended to ventricular tachycardia ablation, showing promising results in pre-clinical and clinical studies. However, the evidence of using PFA in VT ablation was spare and limited to case reports, small case series and short-term studies. The optimal role and safety of PFA in VT ablation remained unknown. Purpose The aims are to study: 1) procedural safety of combined PFA and RFA in VT ablation; 2) clinical outcome of combined PFA and RFA; 3)comparing result with RFA Methods This is a single centre retrospective study. From 1/7/2023 to 1/11/2025, patients enrolled in VT ablation of monomorphic VT were included. All VT ablation was performed initially with RFA and additional PFA was used at the operators' discretion. A pentaspine catheter was used for PFA under the guidance of EAM, ICE and fluoroscopy. The endpoints were safety endpoints (procedural complication and PFA related adverse events) and clinical outcomes (VT-free survival and MACE). Results A total number of 18 patients (median age 70 year-old, 94% male) were included into the PFA+RFA group (n=7, 39%) and RFA group (n=11, 61%). The procedural and fluoroscopic time were similar between the PFA+RFA group and RFA group(232.2min (IQR 19) vs 217min (IQR 40); 24.1min (IQR 11.5) vs 22.2min (IQR 10) respectively). For complications, there was one anticipated complete heart block in the RFA group. There was no PFA related adverse event (hemolysis, thromboembolism, coronary spasm, VF induced during PFA, mechanical injury due to pentaspine catheter, shock, heart failure) with a median 21.5 PFA applications. There was a trend towards a better VT-free survival in PFA+ RFA group (86% vs 34% at 24 months, PFA+RFA vs RFA) but it was not statistically significant (p=0.17, Chi-Square 1.8). There was less MACE (cardiovascular death, hospitalization for heart failure/ ventricular arrhythmias, non-fatal MI, non-fatal stroke) in the PFA+RFA group (p=0.028, Chi-Square 4.8). Conclusion(s) Combined PFA+RFA in VT ablation is safe and effective. There is no major adverse event or complication associated with the use of a pentaspine catheter for PFA in VT ablation.