Neurodevelopmental status at eight years in children with dextro-transposition of the great arteries: the Boston Circulatory Arrest Trial.

OBJECTIVES: Our goal was to determine which of the two major methods of vital organ support used in infant cardiac surgery, total circulatory arrest and low-flow cardiopulmonary bypass, results in better neurodevelopmental outcomes at school age.

METHODS: In a single-center trial, infants with dextrotransposition of the great arteries underwent the arterial switch operation after random assignment to either total circulatory arrest or low-flow cardiopulmonary bypass. Developmental, neurologic, and speech outcomes were assessed at 8 years of age in 155 of 160 eligible children (97%).

RESULTS: Treatment groups did not differ in terms of most outcomes, including neurologic status, Full-Scale or Performance IQ score, academic achievement, memory, problem solving, and visual-motor integration. Children assigned to total circulatory arrest performed worse on tests of motor function including manual dexterity with the nondominant hand (P =.003), apraxia of speech (P =.01), visual-motor tracking (P =.01), and phonologic awareness (P =.003). Assignment to low-flow cardiopulmonary bypass was associated with a more impulsive response style on a continuous performance test of vigilance (P <.01) and worse behavior as rated by teachers (P =.05). Although mean scores on most outcomes were within normal limits, neurodevelopmental status in the cohort as a whole was below expectation in many respects, including academic achievement, fine motor function, visual-spatial skills, working memory, hypothesis generating and testing, sustained attention, and higher-order language skills.

CONCLUSIONS: Use of total circulatory arrest to support vital organs during heart surgery in infancy is generally associated with greater functional deficits than is use of low-flow cardiopulmonary bypass, although both strategies are associated with increased risk of neurodevelopmental vulnerabilities.