OC227a: Abnormal DV blood flow in the first trimester and detection of complications in monochorionic twins

Abstract

Abnormal nuchal translucency and the reversed flow in the ductus venosus (DV) seem to be a good predictor of certain complications of monochorionic pregnancies, namely: twin-to-twin transfusion syndrome (TTTS), congenital heart diseases or early fetal demise. We analysed 19 monochorionic twin pregnancies at 12–14 weeks of pregnancy. Nuchal translucency thickness (NT1, NT2) was measured and the difference between both twins (NT1–NT2) was calculated. We also studied Doppler blood flow velocimetry in the ductus venosus (ACUSON 128 XP). The appearance of reversed blood flow in the DV during atrial systole was marked. We were able to visualize the DV by colour Doppler facilities and measure the blood flow by applying pulsed wave Doppler (angel of insonation < 30.0). A right ventral mid-sagittal plane of the fetal body was obtained and pulsed wave Doppler was performed in order to record the Doppler blood flow waveforms in the DV. A biweekly ultrasound scanning of the patients followed. We found four cases of abnormal blood flow in the DV and/or abnormal NT1-NT2 (> 0.5). Three of them were associated with cardiac anomaly, TTTS and fetal demise. Abnormal flow in the DV may be an early sign of not only chromosomal abnormalities but also cardiac anomalies or early cardiac dysfunction resulting in TTTS development.