Inferior vena cava thrombosis at its hepatic portion (obliterative hepatocavopathy).

The Budd-Chiari syndrome was primarily described as hepatic vein thrombosis within the liver, but it now includes inferior vena cava (IVC) thrombosis and other conditions that cause hepatic vein outflow obstruction. This author and several others maintain that primary hepatic vein thrombosis and primary IVC thrombosis represent two different clinical disorders. Primary thrombosis of the IVC most commonly occurs in its hepatic portion, which seems to be predisposed to thrombosis and has been called membranous obstruction of IVC, because the thrombus organizes into a fibrous and frequently membranous occlusion of the IVC. The hepatic vein orifices are affected to varying degrees, resulting in congestive liver damage. The cause of IVC thrombosis may be a hypercoagulable state such as coagulation factor deficiency and myeloproliferative disorders, but is more often idiopathic. In Nepal, it is endemic with a suspected association with infections. To consider IVC thrombosis and the congestive liver damage as a disease entity, this author proposes the term obliterative hepatocavopathy, separate from hepatic vein thrombosis. Clinically obliterative hepatocavopathy is less severe in its acute phase compared with hepatic vein thrombosis, but it aggravates occlusion of hepatic vein orifices with recurrent thrombosis. Primary hepatic vein thrombosis and obliterative hepatocavopathy display different hemodynamics of the hepatic veins, IVC, and portal vein; dilatation of the subcutaneous veins in the body trunk is more pronounced in obliterative hepatocavopathy because the ascending lumbar vein becomes the major collateral route. Congestive liver cirrhosis develops after a long clinical course that may be complicated by hepatocellular carcinoma.