White matter microstructure and cognition in adolescents with congenital heart disease

Abstract

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

Study design: 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.

Results: 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).

Conclusion: 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.

Figure 1

Orthogonal collapsed sagittal (A.), coronal (B.), and axial (C.) views of brain map for significant differences in FA for subjects with d-TGA versus controlss. Areas in which subjects with d-TGA white matter FA is significantly lower than that of control subjects is given by gray scale shading and is located in deep white matter of both hemispheres in frontal, parietal, and temporal lobes as well as cerebellum and midbrain. L=left; R=right.

Figure 2

Sagittal, coronal, and axial views of the 6 regions of interest with statistically significant sex-adjusted Pearson correlations between FA and cognitive measures in the subjects with d-TGA.

Figure 3

Regression lines (with 95% confidence intervals) demonstrating the correlation between cognitive outcomes and regional FA in d-TGA subjects (panels a and b) or subjects with d-TGA and controls combined (panels c and d), not adjusting for sex. a) WIAT mathematics composite score increases as left parietal FA increases (sex-adjusted Pearson r=0.39, p=0.006). b) Parent Conners ADHD Index T score decreases, indicating fewer ADHD symptoms, as right precentral FA increases (sex-adjusted Pearson r=−0.39, p=0.006). c) Parent Conners ADHD Index T score decreases, indicating fewer ADHD symptoms, as right ACT FA increases (sex-adjusted Pearson r=−0.23, p=0.04). d) TVPS visual closure score increases as right frontal FA increases (sex-adjusted Pearson r=0.23, p=0.04).