Between January 1970 and December 1974, 389 patients presenting an upper gastrointestinal hemorrhage had an emergency fiberoptic esophagogastroscopy at the time of bleeding. In 103 cases, esophageal and/or gastric varices were visualized and in 46 of these cases, bleeding originiated from varices. Hemodynamic data was available in 19 cases of intrahepatic portal hypertension who had bled from varices. Combined hepatic and umbilicoportal catherterization was perform in 17 cases whereas only hepatic vein catherterization was possible in 2. The portohepatic gradient (FPVP-FHVP or WHVP-FHVP) was utilized as an index of portal hypertension. In the 19 patients studied, the portohepatic gradient ranged from 12 to 24.5 mm Hg with a mean of 18.4 mm Hg; only one patient had a portohepatic gradient of less than 14.5 mm Hg. The present data strongly suggest that in intrahepatic portal hypertension, bleeding varices are observed only if significant portal hypertension exists. Hemodynamic studies may thus be helpful in evaluating bleeding patients with varices particularly when the origin of the bleeding cannot be determined at endoscopy. The finding of a portohepatic gradient of less than 12 mm Hg would strongly suggest that varices were not the source of bleeding and in these cases, shunt surgery should not be considered.