Thirty-five RCTs were included in the review (4,128 participants). Risk of bias in regard to allocation concealment and blinding was reported to be unclear or high in most trials.
Radiofrequency ablation versus antiarrhythmic drug: Significant differences in favour of radiofrequency ablation were found for paroxysmal (RR 2.26, 95% CI 1.74 to 2.94; Ι²=0%; six RCTs) and persistent atrial fibrillation (RR 3.20, 95% CI 1.29 to 8.41; Ι²=74%; five RCTs) for maintenance of sinus rhythm. The inclusion of one particular RCT was purported to account for the much of the heterogeneity found for persistent atrial fibrillation. A significant difference in favour of paroxysmal circumferential pulmonary vein ablation (RR 4.65, 95% CI 2.32 to 9.31; Ι²=52%; two RCTs) compared with antiarrhythmic drugs was also found.
When specific techniques were examined: Wide area pulmonary vein isolation was found to significantly reduce risk of paroxysmal (RR 0.78, 95% CI 0.63 to 0.97; Ι²=40%; six RCTs) and persistent atrial fibrillation (RR 0.64, 95% CI 0.43 to 0.94; Ι²=37%; three RCTs) compared with segmental pulmonary vein isolation. Pulmonary vein isolation/circumferential pulmonary vein ablation with linear lesions was found to reduce risk of persistent (RR 0.53, 95% CI 0.32 to 0.87; Ι²=75%; four RCTs) and paroxysmal (RR 0.93, 95% CI 0.88 to 0.99; Ι²=0%; eight RCTs) atrial fibrillation compared with pulmonary vein isolation/circumferential pulmonary vein ablation alone. Pulmonary vein isolation with complex fractionated electrogram was found to reduce significantly risk of persistent atrial fibrillation compared with pulmonary vein isolation alone (OR 0.53, 95% CI 0.30 to 0.93; Ι²=39%; three RCTs); no significant between group difference was found for paroxysmal atrial fibrillation.
Incidence of complications was also reported.