P13.05: Longitudinal change of time intervals of ductus venosus in growth restricted fetuses

This is the authors' abstract. We don't add key points for this paper.

To investigate the sequential changes of time intervals of ductus venosus (DV) flow velocity waveform (FVW) in fetuses with growth restriction (FGR). Time intervals of systolic (S) and diastolic (D) components of DV-FVW were measured in FGR fetuses. We also calculated the pulsatility index (DV-PI) and the ratio of S to D (S/D ratio). Longitudinal study of FGR fetuses was performed and each index was compared to the reference range. FGR was defined as the estimated fetal weight below -2.0 standard deviation of local standard with elevated umbilical artery pulsatility index more than 95 percentile of the normal reference range. A total of 35 observations were performed (median, 6; range, 3-13) on 5 FGR fetuses. The median gestational age at inclusion and delivery were 25.1 (range, 22.3-27.7) weeks and 28.9 (range, 27.1-30.1) weeks. In FGR fetuses, S/D ratios became lower than the 5th percentile of the normal mean at the median of 20 days (range, 17-46) before delivery and showed almost linear deterioration throughout monitoring. DV-PI of FGR became higher than normal fetuses at the median of 20 days (range, 3-21) before delivery, which was almost the same as S/D ratio, however, S/D ratio seemed to show abnormal values several days earlier than DV-PI in some of the cases. Time intervals of systolic and diastolic phases and their ratio might add some insight to indices already established such as the DV-PI in evaluation of DV-FVW. Further study is needed for of these variables into clinical practice.