RESUMO
OBJECTIVE: To perform a systematic review of randomized controlled trials (RCTs) on catheter ablation for atrial fibrillation (AF). BACKGROUND: Radiofrequency catheter (RF)-ablation around pulmonary vein ostia and in left atrium may reduce or prevent recurrence of AF, as documented in observational studies and registry reports; however, few RCTs are available. METHODS: Using relevant search phrases, Cochrane Library, MEDLINE and EMBASE were searched for RCTs, last time in May 2007. Titles and abstracts were screened. When entry criteria were fulfilled, full-text papers were read and graded according to quality and relevance. RESULTS: One thousand and ninety four abstracts were evaluated, and five RCTs included (578 randomized patients). The studies had moderate quality and relevance, but the results were consistent: ablation is better than drug treatment in preventing AF recurrence; the relative risk (95% CI)) one year after ablation ranged from 0.20 (0.08-0.51) to 0.62 (0.39-0.99). CONCLUSIONS: Results from observational and registry studies are confirmed: RF-ablation reduces recurrence rate of AF, and can be done with few serious complications. Limitations are few patients>70 years, and only one year follow-up.