Cerebroplacental hemodynamics in fetuses with transposition of the great arteries and usefulness in predicting neonatal condition

Abstract

ObjectivesLiterature on cerebroplacental hemodynamics in fetuses with transposition of the great arteries (TGA) is scarce and provides conflicting results regarding possible brain‐sparing effect. Therefore, the aims of our study were to examine the Doppler parameters of the middle cerebral artery (MCA) and the umbilical artery (UA) in a large cohort of fetuses with TGA, and to assess their possible utility in predicting urgent balloon atrial septostomy (BAS) in neonates.MethodsA retrospective observational study including fetuses diagnosed with TGA between 2008 and 2022 and age‐matched normal cohort was conducted in a single tertiary Fetal Cardiology Center. Medical records and echocardiographic examinations were reviewed to collect demographic, sonographic and follow‐up data. Selected Doppler parameters were compared between TGA and normal fetuses, as well as between TGA with and without associated ventricular septal defect (VSD) to assess the impact of this congenital heart defect on cerebroplacental circulation. Additionally, Doppler indices in patients with restrictive foramen ovale (FO) were analyzed to search for potential predictors of urgent BAS. Statistical analyses were performed with Statistica 13 software using descriptive statistics, T‐Student test or U‐Mann‐Whitney test for comparisons and ROC curves to assess predictive value.Results541 examinations of 159 fetuses with TGA (performed between 19 and 40 weeks of pregnancy) and 1300 examinations of age‐matched normal fetuses were included in the study. MCA PI and UA PI followed expected trends throughout pregnancy, with slightly higher values in TGA fetuses, however within the limits for normal population. Cerebroplacental ratio (CPR) values were similar in normal and TGA fetuses. Presence of small VSD did not have clinically important impact on Doppler parameters. Peak systolic velocity (PSV) in the MCA gradually increased after 35 weeks of pregnancy, especially in fetuses who did not develop restriction of the FO after birth. MCA PSV values below 1.16 multiples of median (MoM) measured at 38 weeks of pregnancy or later predicted the need for urgent BAS with 81.4% sensitivity and 52.4% specificity.ConclusionsMCA PI, UA PI, and CPR values in fetuses with TGA usually fall within normal limits throughout pregnancy. Presence of small coexisting VSD does not affect the Doppler parameters significantly. MCA PSV increases in TGA fetuses after 35 weeks of pregnancy, and its value measured in the last prenatal study (optimally after 37 weeks) may serve as an additional predictive factor for urgent BAS.This article is protected by copyright. All rights reserved.