Objective: fetal circulatory characteristics differ from those after birth; the right ventricle assumes more than 60% of the workload in the systemic circulation before birth. The right ventricle automated myocardial performance index (AM+MPI) is a simple, time-efficient, and stable assessment method used to evaluate overall cardiac function. This study aimed to apply the right ventricle AM+MPI technique to explore its role in normal mid-to-late pregnancy fetal cardiac function and compare the AM+MPI differences between diabetic and normal fetuses. Methods: A total of 150 pregnant women who visited the obstetric outpatient department at Daxing Hospital, Xi'an, from January 2022 to June 2022 were selected. We excluded 42 patients with comorbid conditions other than diabetes, fetal anomalies, and unclear last menstrual periods, resulting in 85 healthy pregnant patients and 17 diabetic pregnant patients. Using a Samsung WS80A color Doppler ultrasound diagnostic device, we measured the fetal right ventricle AM+MPI, isovolumic contraction time (ICT), isovolumic relaxation time (IRT), and ejection time (ET) in RMPI mode. We performed variability and correlation analyses within the normal group and compared these parameters with those of the diabetic group. Results: In the healthy pregnant group, there was no significant variability in the fetal MPI, ET, or ICT values among the groups (p > 0.05). However, the IRT was positively correlated with gestational age (p < 0.05), with a linear fit formula of IRT = 29.78 + 0.49 × gestational age (DW value 1.87; F = 32.25, p < 0.05), indicating that the IRT increases with gestational age. The right ventricle MPI in the diabetic group was significantly greater than that in the normal group (p < 0.05). Conclusion: The right ventricle AM+MPI technique is simple, time-efficient, and stable and can objectively assess fetal right ventricle function, providing a theoretical basis for the early diagnosis of intrauterine cardiac function abnormalities. Additionally, there are significant differences in the right ventricle MPI between diabetic and normal fetuses, providing evidence for predicting fetal developmental issues and postnatal complications. The right ventricle AM+MPI holds promise as a new method for prenatal evaluation of fetal right heart function.
Keywords: Right ventricular function; automated myocardial performance index; diabetic pregnant women; fetal; healthy pregnant women.