Two-stage arterial switch for late-presenting transposition of the great arteries†

OBJECTIVES: Ventricular retraining and arterial switch have been described in late-presenting transposition of the great arteries (TGA) in older infants who were unable to undergo neonatal arterial switch operation (ASO) and late survivors of atrial switch with systemic right ventricular dysfunction. There are little data available on patients presenting between these 2 groups. This study aims to review the early and mid-term outcomes of the management of late-presenting TGA with an unprepared left ventricle (LV) by a 2-stage arterial switch. METHODS: The demographic, procedural and outcome data were obtained for all children who underwent LV retraining for late-presenting TGA between 2005 and 2017 at our institution. The primary outcomes were early mortality and extracorporeal membrane oxygenation (ECMO) after arterial switch. RESULTS: Twenty patients were included during the study period, with a median age of 12 months (range 6 weeks-3.3 years). The median time of LV retraining was 48 (range 8-170) days. Indexed LV mass increased from 34 ± 19 g/m2 before LV retraining to 106 ± 85 g/m2 before arterial switch. There was 1 death (5%) after LV retraining. Three patients required ECMO support after arterial switch (15%) despite retraining. During follow-up, there was 1 late death, no late reinterventions or reoperations, and all surviving patients had normal or near-normal LV function at late follow-up. CONCLUSIONS: LV retraining resulted in an increase in LV mass and enabled a 2-stage arterial switch to be carried out with acceptable early and mid-term outcomes. Two-stage arterial switch is a reasonable option for late-presenting TGA. A long-term follow-up is required to assess late LV function after preparation.