Additional Mitral Isthmus Linear Ablation After Roof Linear and Anterior Septal Linear Ablation Is Associated With Improved Sinus Rhythm Maintenance in Patients With Nonparoxysmal Atrial Fibrillation

Background The optimal catheter ablation strategy for non‐paroxysmal atrial fibrillation (non‐PAF) is controversial. We examined the safety, feasibility, and efficacy of a new treatment strategy for non‐PAF, defined as the Pulmonary vein isolation (PVI); left roof linear (RL), Mitral Isthmus linear (MIL), and left anterior SEptal linear (ASL) ablation; and leftatrial appendage (LAA) Device occlusion (PROMISED) procedure. Methods One‐hundred forty‐two patients with non‐PAF underwent PVI + RL + ASL ablation with/without MIL ablation, combined with LAA occlusion (LAAO). The primary end point was atrial arrhythmia recurrence after a 3‐month blanking period. Results Eighty‐two patients underwent the PROMISED procedure (MIL group) and 60 patients underwent PVI + RL + ASL ablation with LAAO without MIL ablation (Non‐MIL group). The baseline characteristics were similar between the two groups. No serious procedure‐related complications occurred during the procedure. Twelve months after a single procedure, atrial arrhythmia recurrence was observed in 17/82 patients (20.7%) in the MIL group versus 31/60 patients (51.7%) in the Non‐MIL group (hazard ratio HR: 0.327 and 95% confidence interval CI: 0.181–0.592; p 5 mm was observed during the 12‐month follow‐up. Overall, 85.2% of the patients discontinued oral anticoagulant therapy within 6 months after the procedure. One patient experienced stroke in the MIL group 10 months after the procedure and one experienced stroke in the Non‐MIL group 2 months after the procedure. Conclusion In patients with non‐PAF, the MIL group, which underwent the PROMISED procedure, was associated with a lower observed 12‐month atrial arrhythmia recurrence rate without an apparent increase in complications.