Cryotherapy ablation of parahisian accessory pathways in children

Background Because of its safety profile, cryoablation has become an alternative therapy for septal arrhythmias, including parahisian accessory pathways (APs). Data regarding its efficacy, safety, and late outcome for parahisian APs in children are limited. Objective The purpose of this study was to evaluate the safety and efficacy of cryoablation of parahisian APs in children. Methods Fifty-nine cryoablations of parahisian APs were performed in 50 patients [76% males; median age 16.5 years (range 5.3–20 years)]. Thirty-three had manifest APs and 17 had concealed APs. The time to effect was defined as the duration of time from reaching –30°C to the disappearance of AP during the cryomapping phase. The acute success rate for the first ablation was 94% (47/50). Results Mean fluoroscopy time and number of cryoablations were 28.5 ± 23.3 minutes and 2.6 ± 1.2 seconds, respectively. The time to effect was 8.5 ± 7.1 seconds. The overall recurrence rate was 14.9%, decreasing from 40% in the first 10 cases to 8.1% in the next 37 ( P