Reduced cerebrovascular reactivity is more pronounced in female than male youth with complex congenital heart defects

Gauthier, C.; Potvin-Jutras, Z.; Sanami, S.; Easson, K.; Gilbert, G.; Saint-Martin, C.; Brossard-Racine, M.

doi:10.1101/2025.11.03.686431

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bioRxiv · 10.1101/2025.11.03.686431

Reduced cerebrovascular reactivity is more pronounced in female than male youth with complex congenital heart defects

Gauthier, C.·Potvin-Jutras, Z.·Sanami, S.·Easson, K.·Gilbert, G.·Saint-Martin, C.·Brossard-Racine, M.

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Abstract

AimsCongenital heart defects (CHD) are the most common neonatal malformations. Neonates with complex CHD present with cerebrovascular dysfunction, including deficits in cerebrovascular reactivity (CVR), a measure of vascular reserve. However, it is unknown whether these deficits persist beyond the perioperative period. Methods and ResultsHere, we compared CVR between 53 youth with CHD and 54 age-matched controls without CHD. CVR was derived using a novel approach based on resting state blood oxygen-level dependent magnetic resonance imaging. We found that youth with CHD present with relative CVR deficits in the whole gray matter and in the anterior cerebral artery territory when compared to controls. Sex differences were identified in the middle cerebral artery territory, with females having lower relative CVR than males in the CHD group. Greater CVR deficits were observed in individuals with single-ventricle as compared to participants with a two-ventricle physiology. Finally, in the CHD group, a lower CVR was found to be associated with reduced performance on the Metacognitive Abilities Index of the BRIEF-A. ConclusionThese results indicate that cerebrovascular deficits in CHD survivors persistent into young adulthood and that CVR offers great promise as a biomarker of cerebrovascular health which could be targeted in future interventions.

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Gauthier, C., Potvin-Jutras, Z., Sanami, S., Easson, K., Gilbert, G., Saint-Martin, C., Brossard-Racine, M.. 2025-11-05. Reduced cerebrovascular reactivity is more pronounced in female than male youth with complex congenital heart defects. https://doi.org/10.1101/2025.11.03.686431

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