Challenging Achievement of Bidirectional Block After Linear Ablation Affects the Rhythm Outcome in Patients With Persistent Atrial Fibrillation

Abstract

Background It is not clear whether bidirectional block ( BDB ) of linear ablations reduces atrial fibrillation ( AF ) recurrence after radiofrequency catheter ablation. We hypothesized that BDB of linear ablation has prognostic significance after radiofrequency catheter ablation for persistent AF . Methods and Results Among 1793 consecutive patients in the Yonsei AF ablation cohort, this observational cohort study included 398 patients with persistent AF (75.6% male; age, 59.8±10.3 years) who underwent catheter ablation with a consistent ablation protocol of the Dallas lesion set: circumferential pulmonary vein isolation; cavotricuspid isthmus ablation ( CTI ); roof line ( RL ); posterior‐inferior line ( PIL ); and anterior line ( AL ). BDB rates of de novo ablation lines were 100% in circumferential pulmonary vein isolation, 100% in CTI , 84.7% in RL , 44.7% in PIL , and 63.6% in AL . During 29.0±18.4 months of follow‐up, 31.7% (126/398) of the patients showed clinical recurrence. Left atrial posterior wall ( LAPW ) isolation ( BDB s of RL and PIL ) was independently associated with lower clinical AF /atrial tachycardia recurrence (hazard ratio, 0.68; 95% CI, 0.47–0.98; P =0.041; log‐rank, P =0.017), whereas BDB s of RL or AL were not (log‐rank, P =0.178 for RL; P =0.764 for AL ). Among 52 patients who underwent repeat procedures (23.0±16.1 months after de novo procedure), the BDB maintenance rates for CTI , RL , PIL , and AL were 94.2% (49 of 52), 63.5% (33 of 47), 62.1% (18 of 29), and 61.8% (21 of 34), respectively. Conclusions Although PIL crosses the esophageal contact area, LAPW isolation is important for better clinical outcome in catheter ablation with a linear ablation strategy for patients with persistent AF.