Abstract 11582: Catheter Ablation of Supraventricular Tachycardia in Patients With Total Cavopulmonary Connection

Introduction: Management of arrhythmias after the Fontan operation is difficult. Total cavopulmonary connection (TCPC), rather than atriopulmonary connection, is considered the optimal method to minimize the risk of arrhythmias, although they are sometimes still observed after TCPC. Catheter ablation (CA) for supraventricular tachycardia (SVT) is extremely difficult after TCPC because the systemic venous route is excluded from the atria. The purpose of this study was to evaluate the efficacy of CA in treating SVT after TCPC. Results: CA was attempted after TCPC in 14 patients aged 8-37 years (median: 23 years). TCPC was performed using the lateral tunnel approach in 5 patients, the intra-atrial conduit procedure in 2, and the extracardiac polytetrafluoroethylene conduit procedure in 7. During CA, the atrium was approached either by a transseptal puncture (12 patients), a fenestration in the patch (1 patient), or suture leakage (1 patient). Transseptal puncture was performed using a conventional Brockenbrough needle in all 12 patients. There were no clinically significant complications and only one unsuccessful puncture. SVT included atrial flutter in 4 patients, atrial tachycardia in 7, atrioventricular reentrant tachycardia (AVRT) via the accessory pathway in 1, and AVRT involving twin atrioventricular nodes in 2. Acute treatment of SVT with CA was achieved in 10 patients (71%), but tachycardia recurred in 3 during follow-up. Deterioration of cyanosis was not observed after transseptal puncture, and closure of the puncture site was confirmed in all 12 patients. Overall, SVT was successfully managed using CA in 7 out of 14 patients (50%), and with medication in the remaining patients. Conclusions: SVT may arise after the TCPC procedure. Puncture of the extracardiac conduit is feasible, and CA can be an effective treatment option for refractory SVT after TCPC.