Survivors of repairs of complex congenital cardiac malformations in infancy have an increased risk of permanent abnormalities in motor, cognitive, expressive, and behavioral functioning. These functional deficits are expressions of complex interactions of environment, including prolonged hospitalization and conditioned child–parental behaviours, alterations of social environment, the effects of physical limitations, biological influences including genetic determinants, prenatal injury, and acquired reversible and irreversible neuronal injury.1,2 The magnitude of the problem is large, with incidence dependent upon the measures used for assessment. Overt postoperative neurologic signs have been recorded in up to one-tenth of postoperative infants and children, with double that rate found in those with abnormalities of the aortic arch.3 A decreased potential for development, based upon parent-sibling models, has been estimated to occur in one-third of survivors.4,5 Evidence of injury is provided by magnetic resonance imaging in up to one-third of patients preoperatively, and between half and nine-tenths postoperatively, although most of these early postoperative changes will disappear.5 Although recent changes in perioperative management are likely to reduce such neurologic injury, their significance remains high.
Response to letter: Sibling models—An underused tool with limitations
