Long Standing Alcohol Abuse - Presence of Esophageal Varices

The portal vein carries approximately 1500 mL/min of blood from the small and large bowel, the spleen, and the stomach to the liver. Obstruction of portal venous flow, whatever the etiology, results in a rise in portal venous pressure. The response to increased venous pressure is the development of a collateral circulation diverting the obstructed blood flow to the systemic veins. These portosystemic collaterals form by the opening and dilatation of preexisting vascular channels connecting the portal venous system and the superior and inferior vena cava. High portal pressure is the main cause of the development of portosystemic collaterals; however, other factors such as active angiogenesis also may be involved. The most important portosystemic anastomoses are the gastroesophageal collaterals. Draining into the azygos vein, these collaterals include esophageal varices, which are responsible for the main complication of portal hypertension and massive upper GI hemorrhage.