Neurodevelopmental Outcomes in Early Adolescence: The Pediatric Heart Network’s Single Ventricle Reconstruction Trial

BACKGROUND: Neurodevelopmental and functional impairments are among the most consequential morbidities for survivors of hypoplastic left heart syndrome after staged single ventricle surgical palliation. The SVRIII trial (Long-Term Outcomes of Children With Hypoplastic Left Heart Syndrome and the Impact of Norwood Shunt Type) enrolled adolescents, who were randomized to different surgical shunt types at the time of Norwood procedure as neonates, for multifaceted in-person evaluation. This study reports their neurodevelopmental outcomes. METHODS: Transplant-free survivors from SVRIII were invited to complete an in-person comprehensive neurodevelopmental evaluation in early adolescence. Outcomes across domains of cognition, academics, learning, memory, and attention, as well as social, emotional, behavioral, adaptive, and executive function, were compared with those of normative populations. Associations with demographic and medical covariates, including Norwood shunt type, were also assessed. RESULTS: Among 549 participants enrolled in the SVR trial (Single Ventricle Reconstruction), 200 of the 237 SVRIII participants (84%) completed a neurodevelopmental evaluation at a mean age of 11 years (range, 10 to 14 years). SVRIII participants who did versus did not undergo evaluation were more likely to be male (63% versus 51%), to be White (87% versus 76%), and to have a higher Childhood Opportunity Index score (61±26 versus 46±39). Full-scale intelligence quotient (88±18) was significantly lower than in the normative population, with 39% >1 and 15% >2 SD below the normative mean. Similar patterns were seen for reading (38% >1 SD and 16% >2 SD below the normative mean) and math (38% >1 SD and 19% >2 SD below the normative mean) scores. Attention, executive functioning, social development, visual memory, and adaptive functioning were all more impaired than in the normative population. Measures of socioeconomic status, number of medical complications, and requirement for a gastrostomy tube were each independent predictors of neurodevelopment, with socioeconomic status the most consistently significant factor across models. Group differences by shunt type were inconsistent across neurodevelopmental domains without a clear benefit of one surgical strategy. CONCLUSIONS: In early adolescence, transplant-free survivors of surgical palliation for hypoplastic left heart syndrome show concerning impairments across all domains of neurodevelopment. The distribution of affected outcomes is broad and associated with demographic, medical, and, most frequently, socioeconomic factors. Our findings support recommendations for neurodevelopmental evaluation during adolescence to guide individualized interventions to promote educational success and psychosocial well-being. REGISTRATION: URL: https://www.clinicaltrials.gov; Unique identifier: NCT02455531.