Neurocognitive deficits in children requiring heart transplantation during infancy

Heart transplantation (HTx) is the treatment of choice for infants with end stage heart failure, but data about neurodevelopmental problems of these children are rare. Our aims were to assess the neurological and cognitive outcome of children necessitating HTx during the first two years of life, and to investigate which factors contribute to neurocognitive deficits.

From 1988 to 1999, 59 patients underwent HTx until the age of two years in our institution. 17 subjects (29%) died and 2 were lost during follow-up. 38 out of the 40 remaining infants could be re-examined 10 years thereafter or later. Mean age at re-examination was 13.6yrs (range 11–23yrs). Re-evaluation included a detailed neurological examination and assessment of the intelligence coefficient (IQ) by means of the Culture Fair Test (CFT20-R). The following risk factors were extracted from the records: waiting time until HTx, duration of cardiopulmonary bypass, duration of deep hypothermic arrest, additional operations with heart-lung machine, cardiac decompensation, and relevant organ rejections.

Mean IQ was 86±13 (range 63–111). 18 patients (47%) had IQs within the normal range (≥85), 16 (42%) within the range of learning disability (84–70), and 4 (11%) were mildly mentally retarded (IQ <70). 4 subjects (11%) had distinct neurological deficits (i.e. hemiparesis or tetraparesis). Cardiac decompensation before transplantation was significantly more frequent (p=0.03) in patients with an IQ <85 (9 out of 20=45%) than in those with an IQ ≥85 (3 out of 18=17%), while all other variables were not significantly different between the two groups.

This study showed that neurocognitive deficits are frequent in infants requiring HTx. Our data suggest that cardiac decompensation prior to HTx is an important risk factor for later cognitive deficits, and indicate that prevention of cardiac decompensation may improve the neurocognitive outcome of such patients.