110: Prenatal cerebral lactate predicting delivery mode during labor in fetuses with congenital heart disease

Abstract

To determine whether cerebral lactate as measured on fetal MR spectroscopy (MRS) is predictive of cesarean delivery (CD) during labor in pregnancies complicated by complex congenital heart disease (CHD). We performed an exploratory secondary analysis of a prospective cohort study of term women with singleton gestations who had fetuses with CHD that would require neonatal open-heart surgery. All patients underwent fetal MRI with spectroscopy (MRS) and cerebral lactate was quantified using LCModel. Primary outcome was incidence of unscheduled CD. Secondary outcomes included neonatal resuscitation outcomes. A total of 79 women underwent a fetal MRI at a mean gestation of 32 weeks (range: 20.8-39.0 weeks); 41 (51.9%) of which had positive cerebral lactate in the fetus. Demographic data including maternal age, gestational age at delivery and classification of fetal CHD did not differ between groups. However, fetuses with positive cerebral lactate were studied earlier in gestation in comparison to fetuses without lactate (30.9 ± 4.3 weeks vs 33.2 ± 4.1 weeks, p = 0.02). In the 41 fetuses with lactate, 10 (24.4%) were delivered via CD during labor in comparison to 7 fetuses (18.4%) without fetal lactate, p = 0.52. Fetuses with detectable cerebral lactate delivered via spontaneous vaginal delivery (SVD) with an incidence of 51.2% (21/41) in comparison to 36.8% (14/38) of fetuses without cerebral lactate, p = 0.20. Apgar score at 5 minute was significantly lower in the lactate group 8.0 ± 0.2 vs 9.0 ± 0,2, p <0.001). Initial infant blood gas as well as postnatal lactate were not different between groups. In this pilot study of term fetuses with CHD we report that in utero cerebral anaerobic metabolism is commonly detected. The presence of prenatal cerebral lactate at fetal MRI in fetuses with CHD is undoubtedly complex. Further work is needed to determine the cause and consequence of prenatal cerebral lactate on postnatal outcome in CHD fetuses.View Large Image Figure ViewerDownload Hi-res image Download (PPT)