Abstract
BACKGROUND: Children with congenital heart disease (CHD) experience neurodevelopmental challenges, arising in part from altered brain maturation beginning in utero. There are currently no prenatal interventions to mitigate this risk. Foetal CHD is associated with alterations in maternal blood pressure (BP), for which therapies are available, so we investigated associations between maternal BP, foetal cerebral haemodynamics, and brain growth in foetuses with and without CHD.
METHODS: Our single-centre retrospective cohort study first analysed maternal BP during pregnancy stratified by foetal CHD (n = 494), other foetal anomalies (n = 769), or no foetal anomalies (n = 111). We then performed a prospective study linking maternal BP with foetal brain MRI and cerebral and umbilical Doppler measures in pregnancies with foetal CHD (n = 97 MRI; 121 Doppler) and those with no foetal anomalies (n = 111 MRI; 86 Doppler).
FINDINGS: Mothers carrying a foetus with CHD showed a distinct BP profile compared with unaffected controls and non-CHD foetal anomaly pregnancies. In CHD pregnancies, but not in controls, lower maternal diastolic BP was associated with lower cerebrovascular resistance, lower cerebroplacental flow ratio, and an attenuated reduction in foetal cortical surface area in sensorimotor, frontal and temporal cortical regions.
INTERPRETATION: Lower maternal diastolic BP may reflect adaptive maternal-foetal circulatory coupling that enhances foetal cerebral perfusion and mitigates cortical growth impairment in CHD. We observe a link between maternal haemodynamics and foetal brain maturation in CHD, warranting further exploration in interventional studies.
FUNDING: Supported by the NINDS (R01NS114087, K23NS101120), NIBIB (R01EB031170), NHLBI (K08HL157653), AAN Clinical Research Training Fellowship, BBRF Young Investigator Awards, and the Farb Family Fund.