Abstract 12831: The Association of Fetal Cerebrovascular Resistance on Early Neurodevelopmental Outcome in Hypoplastic Left Heart Syndrome and Other Single Ventricle Anomalies
Background: Fetuses with congenital heart disease (CHD) demonstrate diminished cerebrovascular resistance, a finding that is associated with poor neurologic outcomes in other fetal disease states. Children with hypoplastic left heart syndrome (HLHS) and other single ventricle lesions are at risk for impaired neurodevelopment (ND). We evaluated the relationship of cerebrovascular resistance to ND in fetuses with complex CHD.
Methods: In the Pediatric Heart Network Single Ventricle Reconstruction (SVR) and Infant Single Ventricle (ISV) trials, 14-month ND was assessed using the Psychomotor (PDI) and Mental (MDI) Development Indices of the Bayley Scales of Infant Development®_II. We investigated associations between fetal cerebrovascular resistance and ND scores using middle cerebral artery pulsatility index (MCA-PI) z-scores for gestational age, a Doppler derived parameter obtained by fetal echocardiography. A lower MCA-PI z-score was considered to represent lower cerebrovascular resistance.
Results: ND assessments were performed at age 14.3±1.0 months in 170/230 (74%) ISV and 321/555 (58%) SVR subjects. Fetal cerebral Doppler data was available in 119 ISV/SVR subjects at a mean gestational age of 27.2±5.1 wks; 72/119(61%) had ND scores and 59/72(82%) of these had HLHS. Mean MCA-PI z-score was -0.95±1.52 and did not differ between subjects with and without ND scores. Mean PDI (76±20) and MDI (89±17) scores were lower than normative means (100±15, P<.001). MCA-PI z-score correlated negatively with PDI score (R=-.27, P=.022) but was not associated with MDI score. When MCA-PI z-score was added to a multivariate model controlling for factors found in the SVR trial to predict PDI, the percent of explained variation in PDI increased from 23% to 30% and fetal MCA-PI z-score remained an independent predictor (β=-3.86, P=.031).
Conclusion: Among fetuses with HLHS and other single ventricle anomalies, lower cerebrovascular resistance is associated with higher neurodevelopmental score at 14 months. This relationship is opposite to that observed for fetuses with intrauterine growth retardation and may represent a unique ability of CHD fetuses to compensate for the diminished cerebral oxygen delivery that is secondary to structural heart disease.
- © 2011 by American Heart Association, Inc.