Radiofrequency catheter ablation at the non-coronary cusp for the treatment of para-hisian accessory pathways

Radiofrequency catheter ablation (RFCA) is well established as a definitive therapy of accessory pathways (APs). Successful RFCA of anteroseptal APs at the non-coronary cusp (NCC) have been reported in several case reports. We aimed to evaluate the prevalence, safety, efficacy, and long-term outcome of RFCA at the NCC for the treatment of para-hisian APs.Our study included 17 patients (58.8% female, mean age 46.9 ± 15.9 years) with para-hisian APs. We performed two different ablation approaches which targeted at either the right anterior septum (RAS) (n = 10) or the NCC (n = 7) as the initial target. We compared safety, efficacy, and long-term outcome between these two approaches. The para-hisian APs were successfully ablated in 15 patients and damaged in 1 patient, for the remaining patients, the ablation was abandoned for the suspicion of no atrioventricular conduction. Considering all ablation sites of the para-hisian APs, radiofrequency (RF) delivered at the NCC had a higher success rate (11/12 vs. 5/12, P < 0.05) and a lower complication rate (0/12 vs. 4/12, P < 0.05) compared with the RAS. During a mean follow-up period of 22.4 ± 15.0 months, all the patients were free of arrhythmias without any anti-arrhythmic drugs.Para-hisian APs can be safely and effectively ablated at the NCC. Compared with the ablation at the RAS, RF delivered at the NCC has a higher immediate success, lower complication rate, and good long-term outcome.