A portacaval anastomosis (also known as porto-systemic anastomosis or portal caval system) is a specific type of anastomosis that occurs between the veins of portal circulation and those of systemic circulation. The inferior end of the esophagus and the inferior part of the rectum are some of the most important sites of portal systemic anastomosis.
In portal hypertension, as in the case of cirrhosis of liver, the anastomoses become congested and form venous dilatations. Such dilatation can lead to esophageal varices and rectal hemorrhoids. Caput medusaes can also result.
Specific types include:
It can be one of the conditions caused by portal hypertension. A useful mnemonic is that portal hypertension causes problems in the butt, the gut, and caput. A dilated inferior mesenteric vein may or may not be related to portal hypertension. Other areas of anastomosis include:bare area of the liver as it connects to the diaphragm, the posterior portion of the gastrointestinal tract as it touches the posterior abdominal wall, as well as the posterior surface of pancreas.