Severity of Fetal Brain Abnormalities in Congenital Heart Disease in Relation to the Main Expected Pattern of in utero Brain Blood Supply

Abstract

Objectives: We evaluated the hypothesis that in fetuses with congenital heart disease (CHD) there is a correlation between the expected pattern of in utero brain blood supply and the severity of neurodevelopmental impairment. Methods: A total of 58 fetuses with CHD and 58 controls underwent a Doppler ultrasound and fetal MRI at 36-38 weeks. Fetuses with CHD were divided into two functional classes: class A with an expected severe reduction in oxygenated brain blood supply (left outflow tract obstruction and transposition of great vessels) and class B with theoretically near-normal or mildly impaired oxygenated brain blood supply (other CHD). Head biometry and cerebroplacental Doppler were assessed by ultrasound, and brain volumetry, cortical development and metabolism by MRI. Results: Both class A and B CHD fetuses had significant differences in head biometry, brain perfusion, cortical development and brain metabolism compared with controls. However, there was a significant linear tendency for head biometry, cerebral Doppler, volumes, cortical sulcation and metabolic ratios across the three clinical groups, with signs of more severe brain alterations in type A CHD fetuses. Conclusions: All fetuses with CHD showed significant brain developmental changes, but differences were more pronounced in CHD associated with an expected severe reduction in oxygenated blood supply to the brain.

Fetal brain imaging in isolated congenital heart defects – a systematic review and meta‐analysis

“…Possible duplicate cohorts were identified in three publications . The data of five articles (duplicate cohorts not included) were summarized to a prevalence estimate of cerebral abnormalities of 18% (95% CI −6; 42) . Structural brain anomalies were present in 3% (95% CI −1; 8).…”

Growth patterns in fetuses with isolated cardiac defects

“…A reduction in fetal brain volume has been reported in infants with different types of CHD . This is also reflected by smaller fetal and neonatal head circumferences (HCs) …”

“…Until recently, brain injury and neurodevelopmental delay in these infants were linked to cardiac surgery and cardiopulmonary bypass after birth. However, there is growing evidence that at least part of the brain injuries is already present before surgery and possibly even before birth, as suggested by early postnatal transfontanellar ultrasound and magnetic resonance imaging studies showing structural brain lesions and reduced brain volume prior to cardiac surgery . A reduction in fetal brain volume has been reported in infants with different types of CHD .…”

Relationship Between Cavum Septi Pellucidi Measurements and Fetal Hypoplastic Left Heart Syndrome or Dextro‐Transposition of the Great Arteries

“…However, when the hypoxemia is severe, permanent cell death will become inevitable . Common abnormal findings in fetuses with CHD include increased cerebral blood flow, reduced brain fissures depth and brain volume, smaller head size, and structural brain abnormalities . Volumes of brain regions containing large numbers of neurons are most likely to be affected.…”