Prenatal diagnosis of abnormality of the umbilical portal DV complex: difficulty in universal classification due to various alternative routes in hepatic circulation for placental drainage

Objective To review our experience with fetal abnormality of the umbilical-portal-DV complex and to discuss the new classification system for umbilical portal systemic venous shunts (UPSVS) according to our cases. Methods This study was a retrospective analysis of fetuses with a prenatal diagnosis of abnormality of the umbilical-portal-DV complex. The integrity of the fetal umbilical-portal ductus venosus complex and the hepatic venous system were evaluated using two-dimensional color Doppler sonography. The origin of the shunt, the location of the drainage, and the presence or absence of intrahepatic portal venous system and DV were noted. Results 35 cases of abnormality of the umbilical-portal-DV complex were identified. Agenesis of ductus venous was detected in 33 of them. Based on the abnormality of the umbilical-portal-DV complex, we divided the cases into five groups. Group 1, ductus venosus agenesis with normal hepatic venous anatomy (n = 11); Group 2 downward displacement of the umbilical-portal-DV complex (n = 13); Group 3, umbilical-systemic shunt (n = 5); Group 4, intrahepatic portosystemic shunt (n = 4), Group 5, hepatic arteriovenous malformation (n = 2). Three different intrahepatic portosystemic shunt and one different downward displacement of the umbilical-portal-DV complex cases were detected. Conclusions Disruption of the normal anatomy of the umbilical-portal-DV complex causes various alternative pathway of the placental drainage. This illustrates highlights the challenge of creating a universal classification.