The role of the Mod-MPI in identifying cardiac dysfunction in FGR fetuses stratified by umbilical artery flow abnormalities.

BACKGROUND

Fetal growth restriction (FGR) is a major cause of perinatal morbidity and mortality. In patients with absent end-diastolic flow (AEDF) in the umbilical artery, placental insufficiency is typically severe, and adverse neonatal outcomes are common. The modified myocardial performance index (Mod-MPI) provides a noninvasive assessment of global fetal cardiac function; however, its relationship with Doppler findings and perinatal outcomes in patients with FGR remains under investigation.

METHODS

This prospective observational study included 217 singleton pregnancies between 24 + 0 and 36 + 0 weeks of gestation. Among these, 103 fetuses were diagnosed with FGR and subdivided on the basis of the presence (n = 47) or absence (n = 56) of AEDF. The control group included 114 gestational age-matched fetuses with normal growth and Doppler findings. Left ventricular Mod-MPI and cardiac time intervals were measured via a standardized pulsed-wave Doppler technique on the basis of valvular motion timing. The mitral inflow E- and A-wave velocities were also recorded. Perinatal outcomes such as gestational age at delivery, birth weight, 5-minute Apgar score, and NICU admission were compared.

RESULTS

Although the mean Mod-MPI values were not significantly different between the groups (p = 0.38), AEDF-positive fetuses had shorter ejection times and significantly lower mitral E and A velocities (p < 0.001). These findings indicate impaired diastolic function. Compared with other groups, AEDF-positive fetuses were delivered earlier, had lower birth weights, and had higher NICU admission rates (p < 0.01).

CONCLUSIONS

In fetuses with FGR, the presence of AEDF is associated with early signs of cardiac dysfunction and poor perinatal outcomes. While the mean Mod-MPI may not differ markedly, its components reflect significant hemodynamic compromise. Mod-MPI may be a useful adjunct for monitoring fetal well-being in cases of severe placental insufficiency.