Foetal Modified Myocardial Performance Index as a Predictor of Pregnancy Outcome in Gestational Diabetic Mothers: A Prospective Observational Study

Introduction: Foetuses of mothers with Gestational Diabetes Mellitus (GDM) are at increased risk for cardiac complications even with metabolic control. Conventional Doppler methods often fail to detect early cardiac dysfunction in these cases. The Modified Myocardial Performance Index (Mod-MPI) offers a sensitive and non-invasive tool for early detection of foetal cardiac impairment in GDM pregnancies. Aim: To assess foetal cardiac function using Mod-MPI by doppler in gestational diabetic mothers in early third trimester (28-32 weeks) and to evaluate its utility in prediction of perinatal outcome. Materials and Methods: The present prospective observational study was conducted at VMMC and Safdarjung Hospital, New Delhi, India, from November 2017 to November 2018. A total of 30 singleton pregnant females in the third trimester (28-32 weeks) with a known history of GDM and 30 singleton pregnant females in the third trimester with no history of GDM were included. Patients with multiple pregnancy intrauterine growth retardation, Pre GDM, congenital anomalies, history of cardiac disease or hypertension were excluded from the study. Using doppler ultrasonography, the Mod-MPI was calculated in the foetal left ventricle. Multiple statistical tests and Receiver Operating Characteristic (ROC) analysis was used to determine the optimal Mod-MPI cut-off for predicting adverse foetal outcomes. A p-value <0.05 was considered statistically significant. Results: The pregnant females with GDM had significantly higher mean MPI (0.67±0.14) compared to those females without GDM (0.47±0.08). The mean age in the cases was 26.77±3.45, and in the controls, it was 26.87±3.7 years. Abnormal outcomes were recorded in 9 of 30 foetuses of gestational diabetic mothers, and these foetuses had significantly higher MPI measurements (0.85±0.06), compared to the 21 GDM foetuses who had normal Mod-MPI (0.6±0.09) values without any adverse outcome. The MPI served as an excellent predictor of adverse outcomes in GDM foetuses with a total area under the ROC curve being 0.98. Three abnormal outcomes were recorded in the control group, including Apgar <7, stillbirth, and Intensive Care Unit (ICU) admission. Conclusion: Mod-MPI has the potential to predict adverse pregnancy outcome and improve foetal surveillance in gestational diabetes.