Abstract Body (Do not enter title and authors here): Background: We have previously demonstrated that single ventricle patients (pts) who have undergone the Fontan are known to exhibit brain injury (BI) and abnormalities in cerebral blood flow (CBF). However, it remains unclear whether BI and altered hemodynamics are associated with adverse neurodevelopmental (ND) outcomes, which was the purpose of this project.
Methods: This prospective study included Fontan pts who underwent cardiac and brain MRIs within 2 days of undergoing ND testing. CBF and cardiovascular hemodynamics were measured such as aortic flow, caval return, and pulmonary arterial and venous flow. Systemic to pulmonary collateral flow as well as fenestration flow were calculated. BI included bleeds, focal brain injury, generalized insults and susceptibility-weighted imaging of veins. ND testing included the Adaptive Behavior Assessment System (ABAS), the Wechsler Preschool and Primary Scale of Intelligence–4^th Edition (WPPSI) or Wechsler Intelligence Scale for Children–5^th Edition (WISC) depending upon age, broad math skills, language tests and test of visual motor integration. Classification and Regression Tree (CART) analysis was performed to identify hemodynamic and BI predictors of ND outcome.
Results: A total of 113 pts (65% male, age 10+3 years) were studied. Systemic to pulmonary collateral (Coll) flow >0.5 liters/minute/m² was the most important predictor of a poor ABAS score and of those pts in that category, those with 2 or more focal brain injuries had a poorer ABAS score than those who did not. For intelligence measures, total systemic venous return (Qs) < 2.6 liters/minute/m² was the most important and sole predictor of a poor WPPSI/WISCI scores. See figure. Broad math skills, language tests and test of visual motor integration did not have any hemodynamic or BI predictors identified.
Conclusions: Both elevated Coll flow (which diverts CBF away from the brain) and BI are associated with poorer adaptive behavior while reduced effective systemic flow (Qs) is predictive of lower intelligence for Fontan patients. No CBF or hemodynamic metrics could predict broad math or language skills and visual motor integration.