Early U.S. Experience With Catheter Ablation of Ventricular Arrhythmias With a Dual-Energy Lattice-Tip Catheter

BACKGROUND: Catheter ablation of ventricular arrhythmias (VAs) with conventional small-tip radiofrequency ablation (RFA) catheters is limited by inadequate lesion size and small footprint design. OBJECTIVES: This early U.S. experience investigated procedural and clinical outcomes of VA ablation with a lattice-tip wide footprint catheter that allows toggling between RFA and pulsed field ablation (PFA). METHODS: The Cleveland Clinic VT (CLEAR-VT) Registry is a prospectively maintained registry of consecutive patients undergoing catheter ablation of VAs. Patients undergoing catheter ablation of VA with an RFA/PFA lattice-tip catheter (Sphere-9; Medtronic) between January and September 2025 were analyzed. RESULTS: A total of 59 patients (median age 70 years; mean left ventricular ejection fraction 36.3% ± 12.3%) underwent ablation of VA using the lattice-tip catheter during the study period. Of these, 50 (85%) had scar-related ventricular tachycardia (VT) (28 with ischemic, 19 with nonischemic, and 3 with mixed cardiomyopathy), and 9 (15%) had frequent premature ventricular contractions (PVCs). Acute procedural success, defined as non-inducibility of any VT (excluding nonclinical VTs with cycle length ≤240 milliseconds) or complete PVC suppression, was achieved in 78% and 100% of patients, respectively. After a median follow-up of 100 days (Q1-Q3: 51-172 days), VT recurred in 9 patients (18%), and death/heart transplantation/left ventricular assist device implantation occurred in 6 patients (12%). At 6 months, the Kaplan-Meier-estimated VT-free survival was 69.8% (95% CI: 54.0%-90.3%); the Fine-Gray cumulative incidence of VT recurrence, accounting for competing risks, was 28.4% (95% CI: 11.0%-45.8%). No patient with PVCs had recurrence after a median follow-up of 54 days (Q1-Q3: 40-71 days). Three major procedure-related complications occurred, including 2 major bleeding events and 1 implantable cardioverter-defibrillator system failure after PFA application approximately 7.5 mm from the tip of a left ventricular pacing lead (which required intra-operative device generator change). CONCLUSIONS: In this first U.S. series, catheter ablation of VAs with a lattice-tip RFA/PFA catheter appeared effective and generally safe. Caution should be exercised when applying PFA in proximity to exposed conductors of implantable cardiac devices.