Modified Myocardial Performance Indexis Not Associated with Adverse Perinatal Outcome in Late Onset Fetal Growth Restriction

Aim: The purpose of this study is to investigate the relationship between adverse fetal outcomes and modified myocardial performance index (MPI) values in pregnancies with late-onset fetal growth restriction (FGR). Methods: This is a case-control review of 70 pregnancies with late onset FGR and 42 pregnancies with appropriate for gestational age (AGA) fetuses. Data related with maternal characteristics, ultrasonography findings and perinatal outcomes were recorded. An adverse perinatal outcome was determined with at least one of the following: stillbirth, neonatal death, any Apgar score <7, need for neonatal resuscitation, umbilical cord pH <7.1, and admission to neonatal intensive care unit. Results: Fetuses with late onset growth restriction exhibited a considerably higher umbilical artery pulsatility index (PI) than AGA fetuses (p=0.001). These fetuses also had significantly higher ductus venosus A wave but significantly lower preload index and peak velocity index than AGA fetuses (p=0.017, p=0.016 and p=0.038 respectively). The fetuses with growth restriction and AGA fetuses were statistically similar in aspect of modified MPI values. Adverse fetal outcome was observed in 35 pregnancies (31.3%). When compared to the pregnancies with adverse fetal outcomes, those with favorable fetal outcomes had statistically similar modified MPI values but significantly lower uterine artery PI (p=0.016). Conclusion: There was no significant difference in modified MPI values of fetuses with late-onset growth restriction and AGA fetuses. Moreover, modified MPI values did not differ significantly in pregnancies with adverse fetal outcome and those with favorable fetal outcome. These findings can be regarded as evidence for the mildness and latency of myocardial dysfunction in the pathogenesis of late onset FGR.