Outcomes of a Near-Zero Fluoroscopy and Minimally Invasive Approach in Ablation of Right Free Wall Accessory Pathways in Children

Background: Right free wall (RFW) accessory pathways (APs) represent a relatively rare form of AP, and transcatheter (TC) ablation of these APs carries high procedural failure rates, both with radiofrequency (RF) and cryoenergy. The aim of this study was to report the outcomes of a minimally invasive approach in non-fluoroscopic 3D TC ablation of RFW APs, comparing cryoenergy and RF. Methods: Between March 2010 and March 2024, 62 consecutive patients with RFW APs underwent transcatheter ablation at our institution with a minimally invasive approach. The ablation results were analyzed and compared. Results: The overall acute success rate was 83.9% [52/62 patients; 25/28 (89.3%) for right lateral (RL) APs, 18/19 (94.7%) for right anterior–lateral (RAL) APs, and 9/15 (60.0%) for right posterior–lateral (RPL) APs, p = 0.014], with very limited fluoroscopy use and no complications. There were no significant differences in the acute success rates between the RF and cryoablation groups (32/37 vs. 20/25, p = 0.506). The median follow-up was 24.8 months (IQR 12.5–49.8), and 16 recurrences (30.8%) were observed (3 in the cryoablation group and 13 in the RF group, p = 0.068). The RAL localization of the AP and age > 12 years were predictors of ablation success in multivariate regression analysis. Conclusions: In children, a minimally invasive 3D TC ablation of RFW APs is a completely safe and quite effective approach, with better results for RAL and RL APs, poorer results for RPL APs, and no significant differences between cryoenergy and RF.