OP20.06: Evaluation of the modified myocardial performance index in pregnancies complicated with gestational and pre‐gestational diabetes

Abstract

Objectives: Previous studies suggested that in intrauterine growth restricted (IUGR) fetuses there might be an early vasodilatation of the anterior cerebral artery (ACA). The aim of this study was to assess longitudinally changes in the two segments of the ACA and in the middle cerebral artery (MCA) in IUGR fetuses in relation to changes in the umbilical artery pulsatility index (UA-PI). Methods: A longitudinal Doppler evaluation of 67 IUGR fetuses was performed. IUGR was defined as an estimated fetal weight (EFW) 95th centile). ACA was evaluated in its two segments: S1 just after its origin from the internal carotid artery, and segment 2 (S2) after the junction with the anterior communicating artery. MCA was evaluated after its origin from the circle of Willis. Results: A total of 189 examinations were performed (median per case 2 (range, 1–8)). In IUGR fetuses with normal UA-PI, the proportion of fetuses with a PI below the 5th centile in ACA S1, ACA S2 and MCA-PI was 60.9% 55.5% and 39% respectively (P 95th centile), the proportion of fetuses with reduced PI values in the ACA S1, ACA S2 and MCA was similar (77.5% vs. 70% and 66.6% vs. 70%, respectively). Conclusions: Brain vasodilation seems to start before the umbilical artery PI becomes abnormal, and is earlier expressed in ACA, with no apparent differences between S1 and S2. Therefore, a subgroup of IUGR fetuses with normal PI values in the UA and the MCA already have brain vasodilatation which is not detected with current techniques.