Reduced Cerebellar Volume in Term Infants with Complex Congenital Heart Disease: Correlation with Postnatal Growth Measurements

Similarities and differences in cerebellar alterations between youth born preterm and youth born with congenital heart disease

Individuals born preterm (PT) or with complex congenital heart disease (CHD) present with comparable prevalence of developmental challenges and patterns of neonatal brain injury. Converging evidence also supports that cerebellar development is altered in PT and in CHD survivors. However, no study compared cerebellar integrity between these two groups. This study aims to assess total and regional cerebellar development between youth born PT or with CHD as compared to controls. Participants aged 16-27 years born before 33 weeks of gestational age or who underwent open-heart surgery for CHD during infancy and a group of healthy term-born controls, underwent a brain MRI. Cerebellums were segmented at the lobular level. Youth born PT or with CHD exhibited a comparable pattern of volume reduction affecting total, regional and lobular cerebellar volumes. After adjusting for total brain volume, no significant differences remained between CHD and controls. Only regions and lobules in the anterior cerebellum remained significantly smaller than controls in the youth born PT. Atypical cerebellar development is present in youth born PT and in youth with CHD. However, our results suggested that premature exposure to the extra-uterine environment alters cerebellar development selectively while the cumulative effect of CHD globally hinders brain development.

Critical congenital heart disease beyond HLHS and TGA: neonatal brain injury and early neurodevelopment

BACKGROUND

Characterization of brain injury and neurodevelopmental (ND) outcomes in critical congenital heart disease (cCHD) has primarily focused on hypoplastic left heart syndrome (HLHS) and transposition of the great arteries (TGA). This study reports brain injury and ND outcomes among patients with heterogeneous cCHD diagnoses beyond HLHS and TGA.

METHODS

This prospective cohort study included infants with HLHS, TGA, or heterogenous "Other cCHD" including left- or right-sided obstructive lesions, anomalous pulmonary venous return, and truncus arteriosus. Brain injury on perioperative brain MRI and ND outcomes on the Bayley-II at 30 months were compared.

RESULTS

A total of 218 participants were included (HLHS = 60; TGA = 118; "Other cCHD" = 40, including 8 with genetic syndromes). Pre-operative (n = 209) and post-operative (n = 189) MRI showed similarly high brain injury rates across groups, regardless of cardiopulmonary bypass exposure. At 30 months, participants with "Other cCHD" had lower cognitive scores (p = 0.035) compared to those with HLHS and TGA, though worse ND outcome in this group was driven by those with genetic disorders.

CONCLUSIONS

Frequency of brain injury and neurodevelopmental delay among patients with "Other cCHD" is similar to those with HLHS or TGA. Patients with all cCHD lesions are at risk for impaired outcomes; developmental and genetic screening is indicated.

IMPACT

This study adds to literature on risk of brain injury in patients with critical congenital heart disease (cCHD) diagnoses other than hypoplastic left heart syndrome (HLHS) and transposition of the great arteries (TGA), a heterogenous cohort of patients that has often been excluded from imaging studies. Children with cCHD beyond HLHS and TGA have similarly high rates of acquired brain injury. The high rate of neurodevelopmental impairment in this heterogenous group of cCHD diagnoses beyond HLHS and TGA is primarily driven by patients with comorbid genetic syndromes such as 22q11.2 deletion syndrome.