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.