Zero Fluoroscopy Ablation of Arrhythmias in Patients With Congenital Heart Disease.

Aims: Radiation-free catheter ablation is feasible with modern electroanatomic mapping systems. We aimed to evaluate the feasibility, safety, and outcomes of non-fluoroscopic ablation (NFA) in patients with congenital heart disease (CHD). Methods: We retrospectively reviewed CHD patients who underwent NFA between November 2016 and January 2025. All procedures were performed using the CARTO 3D electroanatomic mapping system. Atrial, ventricular, and aortic geometries were reconstructed as needed. Catheter navigation and sheath placement were guided without fluoroscopy; intracardiac echocardiography was used selectively. Results: Forty-two patients (23 females) with CHD underwent NFA. The median age was 14 years (range 4-56), and median weight was 55 kg (range 19-145). Twenty-one patients had mild, 16 moderate complexity and 5 great complexity CHD. Arrhythmia mechanisms included AVNRT (14%), manifest WPW (21%), high-risk WPW without SVT (5%), concealed pathway AVRT (26%), AFL (12%), AT (14%), and VT (7%). Two patients had both AVNRT and AVRT. Acute success was achieved in all cases without fluoroscopy or acute complications. Over a median 48-month follow-up, three patients had recurrences: one with WPW and Ebstein anomaly, one with ASD/PLSVC and concealed pathway, and one with dual arrhythmia substrates. Conclusion: Zero-fluoroscopy ablation of arrhythmias in select patients with mild moderate or great complexity CHD is feasible, safe, and effective, offering high acute success and low recurrence while eliminating radiation exposure.