Absent ductus venosus, tricuspid regurgitation, cardiomegaly, chorioangioma
Presentation
20 to 24 weeks detailed obstetric ultrasound. First pregnancy.
Patient Data
Genetic sonogram
Absent ductus venosus. Umbilical vein directly connects to the right atrium. Cardiomegaly and tricuspid regurgitation due to right atrial enlargement. Cardio-thoracic ratio was >30%. Hyperdynamic flow in umbilical vein due to placental chorioangioma.
Case Discussion
It is estimated that 20–30% of the blood of the umbilical vein enters the ductus venosus and directly reaches the left heart crossing through the foramen ovale. The remaining well-oxygenated blood flowing in the umbilical vein is distributed to the left lobe of the liver through the left portal vein. The portal blood flow is directed almost entirely to the right lobe of the liver. It is well accepted that the ductus venosus plays a major role in the regulation of fetal circulation by modifying the volume of its flow depending on the pressure gradient between the umbilical vein and the heart.
The literature suggests that the absence of the ductus venosus is associated with a high incidence of adverse fetal outcomes