Classification and functional aspects of portal hypertension

Abstract

Portal hypertension can be classified into two main groups, presinusoidal (intrahepatic and extrahepatic) and intrahepatic. Presinusoidal extrahepatic portal hypertension is unlikely to be associated with hepatocellular failure. Increased splenic flow plays a minor role in its cause. Renal cortical perfusion may be reduced. Causes of presinusoidal intrahepatic portal hypertension include schistosomiasis, myeloproliferative diseases, sarcoidosis, congenital hepatic fibrosis, chronic arsenic poisoning, and primary biliary cirrhosis. Portosystemic shunt operations are well tolerated unless there is associated hepatocellular damage. In cirrhosis, the portal hypertension is presinusoidal, sinusoidal, and postsinusoidal. The problem of bleeding esophageal varices is largely that of hepatocellular failure. The Budd-Chiari (hepatovenous obstruction) syndrome has many causes, including “congenital” webs and trauma. These may be susceptible to a surgical approach.