To describe the relationship between altered white matter microstructure and neurodevelopment in children with dextro-transposition of the great arteries (d-TGA).

We report correlations between regional white matter microstructure as measured by fractional anisotropy (FA) and cognitive outcome in a homogeneous group of adolescents with d-TGA. Subjects with d-TGA (n = 49) and controls (n = 29) underwent diffusion tensor imaging and neurocognitive testing. In the group with d-TGA, we correlated neurocognitive scores with FA in 14 composite regions of interest in which subjects with d-TGA had lower FA than controls.

Among the patients with d-TGA, mathematics achievement correlated with left parietal FA (r = 0.39; P = .006), inattention/hyperactivity symptoms correlated with right precentral FA (r = −0.39; P = .006) and left parietal FA (r = −0.30; P = .04), executive function correlated with right precentral FA (r = −0.30; P = .04), and visual-spatial skills correlated with right frontal FA (r = 0.30; P = .04). We also found an unanticipated correlation between memory and right posterior limb of the internal capsule FA (r = 0.29; P = .047).

Within the group with d-TGA, regions of reduced white matter microstructure are associated with cognitive performance in a pattern similar to that seen in healthy adolescents and adults. Diminished white matter microstructure may contribute to cognitive compromise in adolescents who underwent open-heart surgery in infancy.