Successful radiofrequency catheter ablation of life-threatening atrial tachycardia in an infant with asplenia syndrome.

A 1-year-old infant with asplenia syndrome and congenital heart disease consisting of common atrium, common inlet left ventricle with a common atrio-ventricular (AV) valve, pulmonary atresia, and total anomalous pulmonary venous connection was admitted to our hospital for radiofrequency catheter ablation (RFCA) of supraventricular tachycardia (SVT) before total cavo-pulmonary connection. After antiarrhythmic medications were discontinued for RFCA, she suffered from SVT that resulted in the rapid deterioration of hemodynamic status. Antiarrhythmic medications and cardioversion were not effective in terminating SVT. The baseline electrocardiogram confirmed the existence of twin AV nodes; however, this SVT was revealed to be focal atrial tachycardia (AT) with enhanced automaticity. The origin of AT was not related to surgical scar. Emergent RFCA for AT was successful in our case of asplenia syndrome. AT is a life-threatening complication in a single ventricle and delayed treatment can be fatal. It is important to perform RFCA promptly when drug treatment is not effective. We suggest that the AV node is not always the target site for ablation in patients with asplenia syndrome and twin AV nodes. < Learning objective: In the case of supraventricular tachycardia with asplenia and twin atrio-ventricular (AV) nodes, atrial tachycardia (AT) as well as AV reentrant tachycardia could occur. AT is a life-threatening complication in infants with single ventricle. If drug therapy is not effective, emergent catheter ablation should be performed. AV node is not always the target site for ablation in patients with asplenia and twin AV nodes.>.