Evaluation of fetal myocardial performance index in gestational diabetes mellitus

This study aimed to compare fetal myocardial performance index (MPI) between fetuses of pregnant women with gestational diabetes mellitus (GDM) and healthy controls and to evaluate the relationship between MPI and maternal glucose levels. This was a prospective study of 90 pregnant women, including 50 pregnancies with GDM (27 pregnancies with insulin-regulated GDM and 23 pregnancies with diet-regulated GDM) and 40 healthy controls. Isovolumetric contraction time (ICT) + isovolumetric relaxation time (IRT)/ejection time (ET) were used to calculate the MPI (MPI = [ICT + IRT]/ET). Fetal MPI, PR interval, E/A ratio, maternal plasma glucose levels on the day of MPI measurement, and neonatal outcomes were compared. The fetal left-MPI was significantly higher in the GDM group than healthy controls (0.43 ± 0.04 vs. 0.40 ± 0.06, p = 0.007). The best cut-off level for MPI was >0.41 to predict adverse perinatal outcomes (sensitivity: 70%, specificity: 68%, area under the curve: 0.715, 95% confidence interval: 0.5143–0.8205, p < 0.001). The fetal MPI values showed no correlation with maternal plasma fasting, postprandial glucose, and hemoglobin A1c (HbA1c) levels. Reduced E/A ratio, higher neonatal intensive care unit admissions, and the need for cesarean delivery were detected in the GDM group. Fetal MPI is impaired in women with GDM, and the need for insulin therapy is associated with higher MPI values and adverse neonatal outcomes. Fetal MPI can help detect fetuses with potential adverse outcome risks, owing to impaired fetal cardiac function.