Treatment strategy for Ebstein anomaly with accessory pathways occurring in infancy

Abstract

Background: There are few reports on Radiofrequency Catheter Ablation (RFCA) in Ebstein's Anomaly (EA) associated with tachycardias in infancy. This study aimed to clarify the characteristics of the Accessory Pathways (AP) related tachycardias in EA and to find the strategy to treat EA in infancy. Methods: Patients with APs in EA undergoing RFCA during an 18 yr. period (1995-2012) were enrolled. The age at the time of the RFCA, surgical intervention before the RFCA, and RFCA results were analyzed and compared between patients less than one y.o. and those more than one y.o. Results: Thirty-one sessions in 27 patients (median age 7.6 y.o., female 17, male 10) were performed. The arrhythmias in 12 patients with APs (group Y) occurred at 1 y.o. The age at onset of the tachycardia was 1.7 months and 9.8 y.o. in each group, and the median age and average body weight at the time of the RFCA were 3.8 y.o. and 10kg, and 11.9 y.o. and 35.6kg, respectively. The tachycardias were refractory to multiple Anti-Arrhythmic Drugs (AADs), which were used more in group Y (2.5) than group O (0.5). Brain damage caused by arrhythmias was seen in two patients in group Y before RFCA. The acute success rate was 11 out of 12 (92%) in group Y and 15 out of 15 (100%) in group O, and the recurrence rate was 4 out of 11 (36%), and 1 out of 15 (7%), in groups Y and O, respectively. A failed case involved an AP located on the posteroseptal tricuspid annulus after a Stern's operation which covered the tricuspid annulus by using the artificial patch. The number of applications was 7 in group Y and 6.5 in group O. The complications did not occur in this population. Conclusions: AP related tachycardias in EA during infancy are refractory to AADs and can cause brain damage. The success rate was as high during infancy as in older patients and there were not any complications. RFCA can be indicated in spite of infancy when tachycardias are refractory. It is important to consider the timing and type of surgical correction in terms of the treatment of the arrhythmia.