[Portal hypertension of extrahepatic origin].

Portal hypertension may be due to a suprahepatic or infrahepatic block. Suprahepatic blocks result in Budd-Chiari syndrome. Their principal cause is myeloproliferative syndromes and invasion of the hepatic veins by a tumour. Their main manifestations are ascites and liver enlargement. Treatment consists of re-establishing the hepatofugal drainage. Infrahepatic blocks are due to obstruction of the portal vein, either by thrombosis facilitated by thrombogenic diseases, or by a tumour. Their main consequences are gastrointestinal hemorrhages. Treatment consists of preventing the rupture of oesophageal varices.