Brain Oxygen Perfusion and Oxidative Stress Biomarkers in Fetuses with Congenital Heart Disease-A Retrospective, Case-Control Pilot Study

Fetuses with congenital heart disease (CHD) have circulatory changes that may lead to predictable blood flow disturbances that may affect normal brain development. Hypoxemia and hypoperfusion may alter the redox balance leading to oxidative stress (OS), that can be assessed measuring stable end-products. OS biomarkers (OSB) were measured in amniotic fluid in fetuses with (n = 41) and without CHD (n = 44) and analyzed according to aortic flow, expected cyanosis after birth, and a CHD classification derived from this. Birth head circumference (HC) was used as a neurodevelopment biomarker. CHD fetuses had higher levels of ortho-Tyrosine (o-Tyr) than controls (p = 0.0003). There were no differences in o-Tyr levels considering aortic flow obstruction (p = 0.617). Fetuses with expected extreme cyanosis presented the highest levels of o-Tyr (p = 0.003). Among groups of CHD, fetuses without aortic obstruction and extreme cyanosis had the highest levels of o-Tyr (p = 0.005). CHD patients had lower HC than controls (p = 0.023), without correlation with OSB. Patients with HC < 10th percentile, presented high levels of o-Tyr (p = 0.024). Fetuses with CHD showed increased OSB and lower HC when compared to controls, especially those with expected extreme cyanosis. Our results suggest that increased levels of OSB are more influenced by the effect of low oxygenation than by aortic flow obstruction. Future studies with larger sample size are needed to further investigate the role of OSB as an early predictor of neurodevelopmental problems in CHD survivors.