Persistence of embryonic pattern of hepatocaval venous junction and patent ductus venosus in Budd-Chiari syndrome.

We report an autopsy study on a case of Budd-Chiari syndrome (BCS) in a 44-year-old woman. Dissection showed that the outlets of the right hepatic vein (HV) and of the common trunk of the middle and left HVs appeared as two small depressed areas with narrow ostia. Histological examination showed recent thrombosis of the tributaries of the HVs and centrilobular congestion with necrosis of the hepatic parenchyma. The juxtacaval portions of the major HVs showed a cuneiform shape, because of marked dilation, with thread-like ostia, and multiple small outlets of minor hepatic veins were also present. The coexistence of patent ductus venosus may have prevented the development of the hepatocaval venous junction, with persistence of the embryonic pattern, composed of multiple small channels draining into the right hepatocardiac channel. The unusual hepatocaval venous junction may have predisposed to thrombosis of the HVs, causing BCS.