Evidence of fetal central nervous system injury in isolated congenital heart defects: microcephaly at birth.

OBJECTIVE

We sought to ascertain the risk of reduced fetal brain growth in cases of isolated congenital heart defect (CHD) based on microcephaly at birth.

STUDY

DESIGN

In a case-control study, head circumference was compared in 401 newborns with isolated CHD with 401 control subjects. Microcephaly was defined as head circumference below third percentile. The rates of microcephaly in multiple different categories of major CHD were ascertained along with logistic regression analyses to determine the specific types of cardiac defects that were significantly associated with microcephaly.

RESULTS

Isolated CHD in the fetus was associated with an increased risk of microcephaly as were tetralogy of Fallot, coarctation/aortic arch hypoplasia, and hypoplastic left ventricle syndrome. Tetralogy of Fallot odds ratio, 2.6; 95% confidence interval, 1.1-6.3; P < .04 and coarctation/aortic arch hypoplasia, odds ratio, 2.8; 95% confidence interval, 1.5-5.1; P < .001 were significant independent predictors of microcephaly.

CONCLUSION

The finding of microcephaly at birth in nonsyndromic CHD provides strong evidence in support of intrauterine hypoxic central nervous system damage. Potential changes in prenatal management including aggressive antepartum surveillance and earlier delivery warrant urgent consideration.