Abstract 4553: Pre-Operative Brain Injury in Newborn Infants with Transposition of the Great Arteries Occurs at Similar Rates to other Complex Congenital Heart Disease, and is not Related to Balloon Atrial Septostomy

Abstract

Introduction: Brain injury (BI) in the form of white matter injury (WMI) or ischaemic stroke, seen on magnetic resonance imaging (MRI), is common in neonates with congenital heart disease (CHD). It has previously been suggested that balloon atrial septostomy (BAS) may be an independent risk factor for pre-operative BI in neonates with transposition of the great arteries (TGA). Hypothesis : We hypothesised that: 1. The incidence of BI is similar in neonates with TGA and other severe CHD 2. The risk of pre-operative BI is not increased by BAS Methods: Neonates with TGA, hypoplastic left heart syndrome (HLHS) or pulmonary atresia (PA) were enrolled in a prospective study of BI related to CHD. Pre-operative brain MRI was performed in all patients. In those with TGA who underwent BAS, MRI occurred after septostomy. T1, T2 and diffusion-weighted images were obtained in axial and coronal planes. Scans were reviewed by blinded assessors, and were classified according to WMI (punctate lesions) or ischaemic stroke. Fisher’s Exact Test was used to compare rates of WMI and stroke in each patient group. Results: Sixty-six neonates (mean weight 3.4±0.5kg) were studied, of whom 44 had TGA, 13 had HLHS and 9 had PA. The median age at MRI was 7 days (range 1–31). Thirty-five of the neonates with TGA underwent BAS a median of 1 day (1–21) followed by MRI 7 days (2–12) later. BI was present in 17 (26%) patients. The table shows the incidence of BI in the sub-groups. Two neonates with a stroke also had WMI. Table showing MRI abnormalities in patient sub-groups. Neonates with TGA were not at increased risk of pre-operative BI compared with those with HLHS or PA (p=1.0). BAS did not increase the risk of pre-operative BI in neonates with TGA (p=1.0). Conclusions: Pre-operative BI occurs at a similar rate in neonates with TGA and other severe CHD. The risk of pre-operative BI in neonates with TGA is not increased by BAS.