Arterial switch for transposed great vessels with intact ventricular septum beyond one month of age

Late referral of patients with transposition of the great arteries (TGA) and intact ventricular septum (IVS) is common in China. This study investigates the impact of later age on the arterial switch operation (ASO) performed for TGA-IVS beyond 1 month of age.

From 2000 to 2011, a total 109 patients with TGA-IVS were referred over 1 month of age. In group A, 78 patients with satisfactory left ventricular (LV) geometry underwent a one-stage ASO. In group B, 31 patients with LV regression underwent a two-stage ASO with prior LV retraining.

The median age at ASO was older in group B (6 months, versus group A 1.9 months; p = 0.01). Group A had more frequent patent ductus arteriosus (70.5%, versus group B 38.7%; p = 0.02). The in-hospital mortality was similar in both groups (group A 2.6%, group B 9.7%; p = 0.14). Late mortality was higher in group B (16%, versus group A 2.7%; p = 0.03), as well as aortic regurgitation rate (group A 9.8% versus group B 33.3%; p = 0.01). The median duration of retraining in group B was 18 days. There were no deaths at retraining, although 2 patients required revision of the pulmonary artery banding. The only significant risk factor for late mortality in group B was age at retraining, as continuous variable (p = 0.04). Age beyond 3 months at LV retraining was associated with late impaired LV ejection fraction (p = 0.01).

The overall outcomes of ASO for TGA-IVS performed beyond 1 month of age are satisfactory. Two-stage ASO has higher late mortality and more neoaortic regurgitation. Later age at retraining is associated with higher late mortality. Age beyond 3 months at retraining is associated with impaired LV function.