OBJECTIVE: To assess the association between early anthropometric measurements, device-assisted feeding, and early neurodevelopment in infants with complex congenital heart diseases (CHDs). STUDY DESIGN: Bayley Scales of Infant Development II were used to assess cognitive and motor skills in 72 infants with CHD at 6 and 12 months of age. Linear regression models were used to assess the association between mode of feeding and anthropometric measurements with neurodevelopment at 6 and 12 months of age. RESULTS: Of the 72 infants enrolled in the study, 34 (47%) had single-ventricle physiology. The mean Mental Developmental Index (MDI) and Psychomotor Developmental Index (PDI) scores at 6 months of age were 92 +/- 10 and 81 +/- 14, respectively. At 12 months of age, the mean MDI and PDI scores were 94 +/- 12 and 80 +/- 16, respectively. Lower length-for-age z score (P < .01) and head circumference-for-age z score (P < .05) were independently associated with lower MDI at 6 months, and both increased hospital length of stay (P < .01) and lower length-for-age z score (P = .04) were associated independently with lower MDI at 12 months. Device-assisted feeding at 3 months (P = .04) and lower length-for-age z score (P < .05) were independently associated with lower PDI at 6 months. Both lower weight-for-age z score (P = .04) and lower length-for-age z score (P = .04) were associated independently with PDI at 12 months. CONCLUSION: Neonates with complex CHD who required device-assisted feeding and those with lower weight and length and head circumference z scores at 3 months were at risk for neurodevelopmental delay at 6 and 12 months of age.