Catheter ablation of persistent atrial fibrillation: The importance of substrate modification

Linear Ablation Following Pulmonary Vein Isolation in Patients with Atrial Fibrillation: A Meta-Analysis

Previous studies have given conflicting data regarding the long-term adjunctive efficacy of linear lesions (LLs) on top of pulmonary vein isolation (PVI) as an ablation strategy in patients with atrial fibrillation (AF). The aim of this meta-analysis was to provide a detailed analysis of the available randomized controlled trials (RCTs) regarding the efficacy of LL following PVI in AF patients. Current databases were searched until October 2015. The primary outcome end point of the meta-analysis was recurrence of any symptomatic or documented episode of AF or atrial tachycardia after a single ablation procedure with or without the use of antiarrhythmic drugs. Ten RCTs with a total of 1,446 patients were included in the meta-analysis. The pooled analysis of five trials concerning persistent AF (PeAF) patients (400 in PVI plus LL group and 182 in PVI alone group) suggested that the addition of LL following PVI does not lead to a significant reduction in recurrent atrial tachyarrhythmias compared with PVI alone (relative ratio [RR] = 0.73, 95% confidence interval [CI]: 0.44-1.21, P = 0.22). Similarly, there was no incremental benefit of additional LL in long-term outcomes in paroxysmal AF (PAF) patients (RR = 0.85, 95% CI: 0.68-1.05, P = 0.13). Pooling the results of all eligible trials suggested that PVI plus LL compared with PVI alone significantly increased radiofrequency time (P = 0.0002), fluoroscopy time (P < 0.00001), and procedure time (P < 0.0001). This meta-analysis suggests that LL following PVI does not provide additional benefit to sinus rhythm maintenance in patients with PeAF and PAF.