Budd–Chiari syndrome (BCS) is caused by obstruction of hepatic venous outflow at any level from the small hepatic veins to the junction of the inferior vena ... the portal vein into an outflow ...

The inferior vena cava (also known ... merging into the right renal vein first. This makes the IVC almost symmetrical. Other veins that enter the IVC include the hepatic veins, inferior phrenic ...

Hepatic vein thrombosis associated with inferior vena cava also will not be considered because it is the subject of another review in this issue of Seminars in Liver Disease.