Cognitive outcomes in pediatric heart transplant recipients bridged to transplantation with ventricular assist devices.
BACKGROUND
Ventricular assist devices (VADs) have been associated with high rates of neurologic injury in pediatric patients during the period of support, but the delayed consequences of this type of injury have not been described in the literature.


METHODS
In this study we assess cognitive outcomes with indices of general intellectual functioning, including working memory, processing speed, perceptual reasoning and verbal comprehension, for pediatric heart transplant recipients who required VAD support as a bridge to transplant (n = 9). We present an aggregate of these VAD patients combined with heart transplant recipients who did not require mechanical circulatory support (n = 11), and compare the performance of all transplant patients (n = 20) to typically developing, healthy comparators (n = 12). We also present a post hoc analysis of those transplant recipients with significant medical morbidity in the first year of life, referred to as the "high-risk" transplant group (n = 5), and compare them with the "low-risk" transplant group (n = 15) and the typically developing comparators (n = 12).


RESULTS
The mean performance of the VAD patients was in the average range for each of the examined indices of cognitive functioning. A total of 11% of the VAD patients performed in the impaired range and 78% performed in the average range, with 11% in the superior range on measures of general intellectual functioning. The typically developing participants performed significantly better than the aggregated transplant recipients on all indices except verbal comprehension. Lower cognitive performance in the combined transplant group appears to be associated with medical morbidity in the first year of life.


CONCLUSIONS
Despite significant neurologic risk factors, this cohort of pediatric patients who were bridged to transplant with VAD demonstrated resiliency in terms of cognitive outcomes. In this heterogeneous population, it is likely that multiple factors contributed to the cognitive outcomes. As VAD use becomes more common in pediatric patients, a prospective evaluation of cognitive outcomes is warranted.
Department of Pediatrics, Stanford University School of Medicine, Stanford, California 94305-5731, USA.
Mary Lynette
ML
Stein
Jennifer L
JL
Bruno
Kelly L
KL
Konopacki
Shelli
S
Kesler
Olaf
O
Reinhartz
David
D
Rosenthal
D000293:Adolescent; D002648:Child; D003072:Cognition Disorders / Q000453:epidemiology*; D015897:Comorbidity; D032882:Comprehension; D005260:Female; D016027:Heart Transplantation; D006353:Heart-Assist Devices; D006801:Humans; D008297:Male; D009483:Neuropsychological Tests; D012307:Risk Factors; D055815:Young Adult