Does additional electrogram-guided ablation after linear ablation reduce recurrence after catheter ablation for longstanding persistent atrial fibrillation? A prospective randomized study

Background-Although circumferential pulmonary vein isolation (CPVI) catheter ablation may not be sufficient for long-standing persistent atrial fibrillation (L-PeAF), it is not clear which ablation strategy is beneficial in addition to CPVI. We sought to investigate whether additional complex fractionated atrial electrogram (CFAE)-guided ablation improves clinical outcomes in L-PeAF patients who exhibit continuous atrial fibrillation (AF) after CPVI and linear ablation (Line). Methods and Results-This study enrolled 137 L-PeAF patients (71.4% male, 61.6±10.9 years old) who underwent radiofrequency catheter ablation. We conducted CPVI+Line based on the Dallas lesion set (posterior box+anterior line) after baseline CFAE mapping in all patients. If AF was defragmented (terminated or changed to atrial tachycardia), the procedure was stopped (AF-Defrag group, n=29). If AF was maintained after CPVI+Line, we mapped the CFAE again and randomly assigned the patient to the CPVI+Line group (n=54) or the additional CFAE ablation group (CPVI+Line+CFAE group, n=54). L-PeAF was defragmented during CPVI+Line in 21.2% of patients (29/137, AF-Defrag group). The mean CFAE cycle length was prolonged (P < 0.001), and CFAE area (CFAE cycle length < 120 milliseconds) was reduced (P < 0.001) after CPVI+Line in the remaining patients. Procedure time was longer in the CPVI+Line+CFAE group than the CPVI+Line group (P=0.023), but procedure-related complication rates did not vary. During 22.3±13.2 months of follow-up, the clinical recurrence rates were 17.2% in the AF-Defrag group, 18.5% in the CPVI+Line group, and 32.1% in the CPVI+Line+CFAE group (log rank, P=0.166). Conclusions-Although CPVI+Line reduces and localizes CFAE area, additional CFAE ablation after CPVI+Line does not improve the clinical outcomes of catheter ablation in patients with L-PeAF.