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Abnormal ductus venosus waveforms can arise in a number of conditions ranging from aneuploidy to vascular malformations and fetal tumors. "A wave" reversal can be seen in 5% of euploid fetuses 9.
On Doppler ultrasound, the flow in the ductus venosus has a characteristic triphasic waveform where in a normal physiological situation flow should always be in the forward direction 7 (i.e. towards the fetal heart). This triphasic waveform comprises of: S wave: corresponds to fetal ventricular systolic contraction and is the highest peak
Normal and abnormal ductus venosus waveform patterns. An abnormal DV waveform requires a careful examination of all potential cardiovascular contributory aspects. Table 2 shows a simplified approach with a checklist of conditions that should be considered when an abnormal DV waveform is observed.
This review serves to improve our understanding of the mechanisms that regulate the blood flow redistribution between the fetal liver circulation and fetal heart and the clinical significance of the ductus venosus waveform as generated by pressure-volume changes in the fetal heart.
A normal ductus venosus waveform contains two alternating peaks and two alternating troughs. Assessing variations in these peaks and troughs aid in screening and detection of congenital heart defects, aneuploidies, and fetal growth restriction.
Sampling technique is explained, and normal and abnormal waveforms are illustrated for the ductus venosus, umbilical artery, umbilical vein, middle cerebral artery, and uterine artery. Some examples of clinical cases are provided to illustrate how the results are used in clinical practice.
In fetal growth restriction, an abnormal waveform mandates imminent delivery. In this review, we will discuss the role of ductus venosus assessment and its role in antenatal management and outcome prediction in certain fetal conditions throughout pregnancy.
Abnormal Doppler waveforms in the umbilical vein (UV) (a), ductus venosus (b) and inferior vena cava (IVC) (c). (a) Abnormal UV waveform in hemodynamically compromised fetuses is characterized by the appearance of pulsations. (b) The DV normally has forward blood flow throughout the cardiac cycle.
An abnormal DV waveform requires a careful examina-tion of all potential cardiovascular contributory aspects. Table 2 shows a simplified approach with a checklist of conditions that should be considered when an abnormal DV waveform is observed. Sometimes multiple mecha-nisms can coexist, such as in advanced deterioration of
Doppler velocimetry of the fetal central venous circulation helps identify fetuses with suspected IUGR at an advanced stage of compromise. 5,38 Absent or reversed flow in late diastole in the ductus venosus is associated with increased perinatal morbidity, fetal acidemia, and perinatal and neonatal mortality. 39-41 In one study of 121 IUGR ...