Background and purpose Brain development is impaired in patients with severe congenital heart disease (CHD), although timing and degree of tissue-specific alterations remains unclear. Aim of this study was to compare intrauterine brain development between prospective cohorts of CHD and controls.
Materials and methodsIn CHD and controls, fetal (gestational age 32-34 weeks) and/ or neonatal (term, first month after birth, preoperatively) 3T MRI-scans were segmented. Total brain volume (TBV), cortical (CGM) and deep grey matter (DGM), unmyelinated white matter (UWM), brainstem (BS), cerebellum (CB) volumes were calculated. Cortical development was assessed by inner cortical surface (iCS), cortical thickness (CT), and gyrification index (GI). Linear regression analysis was performed, with correction for postmenstrual age, gender, and birth weight. Linear mixed model analysis was used to assess brain growth.
ResultsAt fetal MRI, BS volume was significantly smaller in CHD (n=21) than controls (n=25) (-15%; p<0.03). At neonatal MRI, TBV (-11%), CGM (-14%), UWM (-10%) and CB (-11%) volumes were significantly smaller in CHD (n=52) compared to controls (n=16) (all p<0.03). iCS (-16%), CT (-3%), and GI (-7%) were significantly smaller in neonatal CHD (p<0.01). Additionally, fetal to neonatal total brain (-11%; p<0.05) and CGM (-24%; p<0.01) volumetric growth rates were decreased in CHD (n=15) versus controls (n=15). Neonates with transposition of the great arteries (TGA, n=19) and single ventricle physiology (SVP, n=18) showed greater intrauterine delay in brain volumetric and cortical development than neonates with left ventricular outflow tract obstruction (n=13).
ConclusionIntrauterine brain development is impaired in CHD, most pronounced in cortical growth, especially in TGA and SVP.