Clinical outcome of electrophysiologically guided ablation for nonparoxysmal atrial fibrillation using a novel real-time 3-dimensional mapping technique results from a prospective randomized trial

Background: Clinical outcomes after ablation of persistent atrial fibrillation remain suboptimal. Identification of AF drivers using a novel integrated mapping technique may be crucial to ameliorate the clinical outcome. Methods and Results: Persistent AF patients were prospectively enrolled to undergo high-density electrophysiological mapping to identify repetitive-regular activities (RRas) before modified circumferential pulmonary vein (PV) ablation. They have been randomly assigned (1:1 ratio) to ablation of RRa followed by modified circumferential PV ablation (mapping group; n=41) or modified circumferential PV ablation alone (control group; n=40). The primary end point was freedom from arrhythmic recurrences at 1 year. In total, 81 persistent AF patients (74% male; mean age, 61.7±10.6 years) underwent mapping/ablation procedure. The regions exhibiting RRa were 479 in 81 patients (5.9±2.4 RRa per patient): 232 regions in the mapping group (n=41) and 247 in the control group (n=40). Overall, 185 of 479 (39%) RRas were identified within the PVs, whereas 294 of 479 (61%) in non-PV regions. Mapping-guided ablation resulted in higher arrhythmia termination rate when compared with conventional strategy (25/41, 61% versus 12/40, 30%; P P =0.38), mapping ( P =0.46), and fluoroscopy times ( P =0.69) were not significantly different between the groups. No major procedure-related adverse events occurred. After 1 year, 73.2% of mapping group patients were free from recurrences versus 50% of control group ( P =0.03). Conclusions: Targeted ablation of regions showing RRa provided an adjunctive benefit in terms of arrhythmia freedom at 1-year follow-up in the treatment of persistent AF. These findings might support a patient-tailored strategy in subjects with nonparoxysmal AF and should be confirmed by additional larger, randomized, multicenter studies. Clinical Trial Registration: URL: https://www.clinicaltrials.gov . Unique identifier NCT02571218.