Design and rationale of the pulse field ablation for postinfarction ventricular tachycardia: The ASCEND-VT pilot study.

BACKGROUND: Ventricular tachycardia (VT) ablation in patients with ischemic cardiomyopathy (ICM) continues to be a challenging procedure with variable outcomes. Most current ablations are done using radiofrequency ablation (RFA). The new pulsed field ablation (PFA) technology may be able to achieve similar or superior procedural outcomes but potentially over shorter periods of time with less intravascular fluid infusion, but this possibility has never been tested. OBJECTIVE: This study aimed to compare the procedural efficacy and safety of VT ablation in patients with ICM using focal PFA vs RFA catheters. METHODS: This ASCEND-VT pilot study is a single-center trial randomizing patients to RFA vs PFA VT ablation in a 1:1 fashion. The new focal PFA catheter will be used under an investigational device exemption granted by the US Food and Drug Administration. Patients with mechanical valves will be excluded. The primary ablation target will be homogenization of endocardial late abnormal ventricular activity. Patients will be followed for 6 months after the procedure. RESULTS: 40 individuals will be randomized. The primary efficacy metric will be the ablation time needed to eliminate late abnormal ventricular activities in each patient. Additional efficacy and safety endpoints will be interrogated after the procedure and during outpatient follow-up. CONCLUSION: This is the first pilot randomized controlled trial comparing the safety and efficacy of focal PFA vs RFA VT ablation in ICM. Its results will inform the design of future larger studies that will further establish the clinical utility of PFA in the context of scar-related VT ablation.