Transseptal or retrograde approach for transcatheter ablation of left sided accessory pathways: a systematic review and meta-analysis

BACKGROUND: Transcatheter ablation is the most effective treatment for patients with symptomatic or high-risk accessory pathways (AP). At present, no clear recommendations have been issued on the optimal approach for left sided AP ablation. We performed this meta-analysis to compare the safety and efficacy of transaortic retrograde versus transseptal approach for left sided AP ablation. METHODS AND RESULTS: MEDLINE/PubMed and Cochrane database were searched for pertinent articles from 1990 until 2016. Following inclusion/exclusion criteria application, 29 studies were selected including 2030 patients (1013 retrograde, 1017 transseptal) from 28 observational single Centre studies and one randomized trial. Patients approached by transseptal puncture presented a significantly higher acute success (98% vs. 94%, p = 0.040). The incidence of late recurrences (p = 0.381) and complications (p = 0.301) did not differ among the two groups, but the pattern of complications differed: vascular complications were more frequent with transaortic retrograde approach, while cardiac tamponade was the main transseptal complication. No difference was noted in terms of procedural duration and fluoroscopy time (p = 0.230 and p = 0.980, respectively). Meta-regression analysis showed no relation between year of publication and acute success (p = 0.325) or incidence of complications (p = 0.795); additionally, no direct relation was found between age and acute success (p = 0.256) or complications (p = 0.863). CONCLUSIONS: Left sided AP transcatheter ablation is effective in around 95% of the cases, with a very limited incidence of complications. Transseptal access provides higher acute success in achieving AP ablation; late recurrences are rare but observed similarly following both approaches. Retrograde approach is affected by a relatively high incidence of vascular complications.