Neurocognitive function of pediatric heart transplant recipients.

Background: Pediatric heart transplant recipients exhibit cognitive delays, as evident in assessments of their general intelligence. Less is known about their specific neurocognitive impairments.

Methods: All 19 children in Finland aged 6 to 16 years who had undergone heart transplantation (HTx) participated. Of these, 12 (63%) had cardiomyopathy (CM) and 7 (37%) had congenital heart disease (CHD). They were assessed on average 5.5 (SD, 3.6) years post-operatively at a mean age of 12.0 (SD, 3.1) years. A standardized test of intelligence (Wechsler Intelligence Scale for Children [WISC]-III), a neuropsychological test battery (NEPSY-II), and a parental developmental questionnaire (FTF) were administered. The neuropsychological test profile of the HTx group was compared with that of a matched control group.

Results: HTx children had a lower mean Performance Intelligence Quotient (PIQ; 82.2, p = 0.001) and Full-Scale IQ (FSIQ; 85.6, p = 0.004) compared with population norms. HTx children scored generally lower than the control group on the neuropsychological tests (p = 0.002). Seven patients with pre-HTx neurologic sequelae (n = 6) or extreme prematurity (n = 1) had lower mean FSIQ (72.1) than did children without major pre-HTx risk factors (93.5, p = 0.012). The latter group scored below average on only 1 of 6 WISC-III sub-tests and 2 of 10 NEPSY-II sub-tests, all measuring visuoconstructional performance.

Conclusions: Children without major neurologic risk factors pre-HTx may have normal general intelligence after HTx but deficits in the visuoconstructional domain.