Adjunct posterior wall isolation reduces the recurrence of atrial fibrillation in patients undergoing cryoballoon ablation: a systematic review and meta-analysis.

Background: Pulmonary vein isolation (PVI) has evolved to be an integral part of ablative therapy for atrial fibrillation (AF), however, recurrence rates of AF remain high even after complete wide area circumferential PVI. In recent years adjunct posterior wall isolation (PWI) has been performed in patients with more persistent forms of AF but the benefits remain unclear. Aim: The objective of this meta-analysis was to evaluate the efficacy of adjunct posterior wall isolation in reducing recurrence rate of AF using cryoballoon ablation (CBA). Methods: We searched PubMed, Google Scholar, Clinicaltrials.gov and Cochrane CENTRAL. We included studies comparing PVI to PVI + PWI in patients with persistent AF undergoing CBA. After data extraction and quality assessment of the studies, we assessed recurrence rates of atrial tachy-arrhythmias (AF, atrial flutter, and atrial tachycardia) as well as total ablation time and procedural adverse events. Risk ratio (RR), mean difference (MD) and 95% confidence interval (CI) were calculated using Review Manager. Results: Concomitant PWI demonstrated significant decrease in recurrence risk of AF (RR 0.48; 95% CI 0.36-0.64; p < 0.00001) as well as all atrial arrhythmias (RR 0.57; 95% CI 0.47-0.70; p < 0.0001). There was no significant difference in adverse events between both groups (RR 1.05; 95% CI 0.43-2.56; p = 0.91), whereas total ablation time was significantly increased in PVI + PWI group (MD 22.67, 95% CI, 7.61-37.73, p = 0.003). Conclusion: Adjunct PWI when compared to PVI alone decreases recurrence rates of atrial tachy-arrhythmias after CBA of persistent AF.