The authors report a case of small bowel bleeding diagnosed by Tc-99m-labeled red blood cell (RBC) scintigraphy during the postoperative period after aortic valve replacement. There is a relationship between aortic valve stenosis and gastrointestinal bleeding in elderly patients, called Heyde syndrome. The described patient had chronic anemia that worsened after surgery. RBC scintigraphy localized the source of bleeding from jejunal angiodysplasia confirmed by mesenteric angiography. This case illustrates the diagnostic information provided by RBC scintigraphy in this syndrome.