Management of Upper Gastrointestinal Hemorrhage Related to Portal Hypertension

Cirrhosis is the most common cause of portal hypertension. When the portal venous pressure gradient exceeds a certain threshold, collaterals develop at sites of communication between the portal and systemic circulations. Three-dimensional computed tomography (CT) and magnetic resonance imaging (MRI) are very useful modalities to image the portal vein and assess for the presence of portosystemic collaterals. The most commonly used method to measure portal venous pressure is an indirect approach in which the hepatic venous pressure gradient (HVPG) is determined. Portal venous pressure is directly related to vascular resistance and portal venous blood flow. Increased intrahepatic vascular resistance occurs in cirrhosis due to both structural changes and endothelial dysfunction, which results in intrahe-patic vasoconstriction. In splanchnic and systemic circulations, endothelial dysfunction leads to arterial vasodilation, which increases splanchnic flow and worsens portal hypertension. Gastroesophageal collaterals are of important clinical significance due to the risk of rupture and variceal hemorrhage.