, for the International Cardiac Collaborative on Neurodevelopment (ICCON) Investigators abstract BACKGROUND: Neurodevelopmental disability is the most common complication for survivors of surgery for congenital heart disease (CHD). METHODS:We analyzed individual participant data from studies of children evaluated with the Bayley Scales of Infant Development, second edition, after cardiac surgery between 1996 and 2009. The primary outcome was Psychomotor Development Index (PDI), and the secondary outcome was Mental Development Index (MDI).RESULTS: Among 1770 subjects from 22 institutions, assessed at age 14.5 6 3.7 months, PDIs and MDIs (77.6 6 18.8 and 88.2 6 16.7, respectively) were lower than normative means (each P , .001). Later calendar year of birth was associated with an increased proportion of high-risk infants (complexity of CHD and prevalence of genetic/extracardiac anomalies). After adjustment for center and type of CHD, later year of birth was not significantly associated with better PDI or MDI. Risk factors for lower PDI were lower birth weight, white race, and presence of a genetic/extracardiac anomaly (all P # .01). After adjustment for these factors, PDIs improved over time (0.39 points/year, 95% confidence interval 0.01 to 0.78; P = .045). Risk factors for lower MDI were lower birth weight, male gender, less maternal education, and presence of a genetic/extracardiac anomaly (all P , .001). After adjustment for these factors, MDIs improved over time (0.38 points/year, 95% confidence interval 0.05 to 0.71; P = .02).CONCLUSIONS: Early neurodevelopmental outcomes for survivors of cardiac surgery in infancy have improved modestly over time, but only after adjustment for innate patient risk factors. As more high-risk CHD infants undergo cardiac surgery and survive, a growing population will require significant societal resources.

Background Survivors of the Norwood procedure may suffer neurodevelopmental impairment. Clinical trials to improve outcomes have focused primarily on methods of vital organ support during cardiopulmonary bypass. Methods In the Single Ventricle Reconstruction trial of the Norwood procedure with modified Blalock-Taussig shunt vs. right-ventricle-to-pulmonary-artery shunt, 14-month neurodevelopmental outcome was assessed using the Psychomotor Development Index (PDI) and Mental Development Index (MDI) of the Bayley Scales of Infant Development®-II. We used multivariable regression to identify risk factors for adverse outcome. Results Among 373 transplant-free survivors, 321 (86%) returned at age 14.3±1.1 (mean±SD) months. Mean PDI (74±19) and MDI (89±18) scores were lower than normative means (each P<.001). Neither PDI or MDI score was associated with type of Norwood shunt. Independent predictors of lower PDI score (R2= 26%) were clinical center (P=.003), birth weight<2.5 kg (P=.023), longer Norwood hospitalization (P<.001), and more complications between Norwood procedure discharge and age 12 months (P<.001). Independent risk factors for lower MDI score (R2= 34%) included center (P<.001), birth weight<2.5 kg (P=.04), genetic syndrome/anomalies (P=.04), lower maternal education (P=.04), longer mechanical ventilation after the Norwood procedure (P<.001), and more complications after Norwood discharge to age 12 months (P<.001). We found no significant relationship of PDI or MDI score to, perfusion type, other aspects of vital organ support (e.g. hematocrit, pH strategy), or cardiac anatomy. Conclusion Neurodevelopmental impairment in Norwood survivors is more highly associated with innate patient factors and overall morbidity in the first year than with intraoperative management strategies. Improved outcomes are likely to require interventions that occur outside the operating room.