[Doppler flow characteristics in ductus venosus between 22-42 weeks in intrauterine growth restriction and normal pregnancies]

The ductus venosus plays an important role in the oxygenated blood supply from the placenta directly to the fetal heart. Uterine blood flow restriction and placental insufficiency can cause intrauterine grow restriction. Permanent hypoxia triggers compensatory mechanisms to protect vital organs. Increased placental resistance and constriction of the fetal peripheral vessels, as evidenced by blood redistribution and increased right ventricular afterload and end-diastolic pressure lead to increased pulsatility in precordial veins. Doppler flow analysis of the DV allows the indirect estimation of the fetal heart function. Because it is not always possible to achieve correct ultrasound beam insonation there have been attempts to use angle-independent indices. The aim of the study was: to compare the Doppler indices in DV in growth restricted and normal fetuses.

208 women were analyzed: 89 women between 22-42 weeks of pregnancy complicated by IUGR and 119 with normal pregnancy as a control group. Ultrasound examination using pulse and color Doppler was performed and PVIV, PIV, PLI and S/D ratio were estimated.

The authors found that for the normal group PVIV, PIV, PLI and S/A decreased with advancing gestation. However in comparison in IUGR group these parameters were substantially higher.

The improvement of maternal and fetal Doppler techniques allows us to distinguish the subgroups of IUGR fetuses with the uteroplacental insufficiency that will have an increased perinatal morbidity and mortality. Alterations in the venous blood velocity waveforms have a more precise relationship with the risk of adverse perinatal outcome than changes in the arterial blood flow usually recognized relatively early in placental function disorders.