Neurodevelopment in 1-year-old Japanese infants after congenital heart surgery

Background: The purpose of this study was to determine the prevalence of persistent neurodevelopmental sequelae in 1-year-old infants after open heart surgery for congenital heart disease, using the Bayley Scales of Infant Development second edition (BSID-II). A secondary objective was to confirm the applicability and usefulness of the BSID-II in Japanese infants. Methods: Thirty-nine infants who underwent repair of a ventricular septal defect before 6 months of age and 108 normal Japanese infants at 1 year of age were assessed using the BSID-II. Results: In normal infants, scores on the Mental Development Index and the Psychomotor Development Index components of the BSID-II ranged from borderline retardation to very superior following a normal distribution similar to those obtained for US controls. No problems were encountered, either in translation or in following the instructions when the BSID-II was used to evaluate the 1-year-old Japanese infants. On the other hand, the mean scores on the Mental Development Index and the Psychomotor Development Index were significantly lower in Japanese patients than in normal Japanese infants, particularly for gross motor development (P < 0.001). Linear regression analysis showed that a longer intensive care unit stay was associated with impaired cognitive development at 1 year of age (P = 0.03). Conclusions: Neurodevelopmental functions in 1-year-old infants with congenital heart disease were lower than those in normal infants, especially for gross motor function using the BSID-II. One risk factor that correlated with neurodevelopmental sequelae was the length of intensive care unit stay.