Transition from fluoroscopic to fluoroless atrial transseptal puncture for pediatric catheter ablation

Introduction Transseptal puncture (TSP) is traditionally guided by fluoroscopy, enabling visualization of instruments but exposing patients and staff to ionizing radiation. The combined use of intracardiac echocardiography (ICE) and 3D electroanatomical mapping systems allows fully fluoroless navigation, though comparative pediatric data remain limited. Objective To assess the safety, efficacy, and outcomes of ICE- and 3D mapping–guided zero-fluoroscopy TSP in pediatric ablation, including cases requiring conversion to fluoroscopy, and to compare results with conventional fluoroscopy-guided procedures. Methods Between September 2022 and October 2025, 99 consecutive pediatric patients underwent primary ICE- and 3D mapping–guided zero-fluoroscopy TSP (ICE group) and were compared with a historical cohort of 50 fluoroscopy-guided cases (Fluoro group, October 2019–August 2022). Patients with a persistent foramen ovale were excluded. Demographic data, procedural success, complications, and radiation exposure were analyzed, focusing on cases requiring conversion to fluoroscopy. Results A total of 149 TSPs (99 ICE, 50 Fluoro) were analyzed. The median age was 14 [IQR 11–16; range 4–18] in the ICE group and 15 [IQR 11–16; range 6–18] in the Fluoro group; median weight 59 [IQR 48.5–67] vs. 63 [IQR 42.5–71.75] kg, respectively. TSP success was 100% in both groups, with no significant differences in complication rates (6.1% vs. 2.0%; p = 0.424). Conversion to fluoroscopy occurred more often in the ICE group (35.4% vs. 20.0%; p = 0.054) but did not increase complications. Rates of pericardial effusion (1.0% vs. 2.0%; p = 0.999) and transient AV block (5.1% vs. 0%; p = 0.169) were comparable. Even with conversion, radiation exposure remained markedly lower in the ICE group: fluoroscopy time (1.64 ± 1.62 vs. 2.87 ± 2.53 min; p = 0.0047), cumulative dose (1.49 ± 5.22 vs. 2.16 ± 3.15 mGy; p = 0.0001), and DAP (15.94 ± 48.20 vs. 20.8 ± 33.4 cGy·cm²; p = 0.0141). Among converted cases, complication, pericardial effusion, and AV block rates (2.22% vs. 5.77%; 0% vs. 1.92%; 2.22% vs. 3.85%; all p > 0.6) were not significantly different. Conclusion ICE- and 3D mapping–guided zero-fluoroscopy TSP is a safe and effective approach for pediatric catheter ablation. Although conversion to fluoroscopy occurred more frequently, it did not impact safety or efficacy. Even when conversion was required, radiation exposure remained significantly lower than in conventional fluoroscopy-guided procedures, supporting this technique as a reliable strategy for minimizing radiation without compromising procedural success.