Ductus venosus agenesis Ductus venosus agenesis with intrahepatic drainage 2024-02-24T10:53:49Z A form of ductus venosus agenesis in which the umbilical vein connects via the portal sinus to the portal venous system (PVS) without giving rise to the ductus venosus. In some cases an intrahepatic shunt from a portal to a hepatic vein can be detected prenatally. This variant has been reported to have a favorable prognosis.