Dual-energy lattice-tip catheter for posterior mitral line ablation: acute efficacy and 1-year outcomes

BACKGROUND: Achieving durable mitral isthmus (MI) block remains challenging. A novel dual-energy lattice-tip catheter enables delivery of both pulsed field (PF) and radiofrequency (RF) energy, potentially improving lesion quality and clinical outcomes. This study aims to assess the feasibility, acute success, safety, and 1-year outcomes of posterior mitral line (PML) ablation using this novel catheter in a multicenter cohort. METHODS: Consecutive patients from two European centers undergoing atrial fibrillation ablation with PML using the dual-energy system (PF-only or PF/RF, at operator discretion) were prospectively enrolled. Primary outcomes were acute MI conduction block, periprocedural complications, and arrhythmia-free survival at follow-up. RESULTS: Among 102 patients, PML was performed with PF-only in 80.4% and PF/RF in 19.6%. Acute MI block was achieved in 92.2% (91.5% PF-only, 95.0% PF/RF, no statistically significant difference). After a median follow-up of 356 days, 74.5% of patients were free from atrial arrhythmia (65.6% in first-time ablation), and arrhythmia-free survival appeared higher with PF/RF than PF-only (85.0% vs 72.0%), but not statistically different. Two major (ventricular fibrillation and coronary vasospasm) and five minor complications were reported. Nine patients (8.8%) underwent redo procedures. Durable MI block was confirmed in two cases, while epicardial gaps accounted for 71.4% of the seven patients with reconduction. CONCLUSION: PML ablation with a dual-energy lattice-tip catheter provided high acute MI block rates, an overall favorable safety profile, and encouraging 1-year outcomes. The potential impact of combined PF/RF energy and epicardial strategies on lesion durability should be evaluated in further randomized studies.