Partial sigmoidectomy and then after 84 days aortic valve replacement were performed as a staged operation on a patient with Heyde syndrome, consisting of aortic stenosis and angiodysplasia of the sigmoid colon. An emergent sigmoidectomy was performed because of continuous bleeding from angiodysplasia of the sigmoid colon. Postoperative arteriography showed the persistence of angiodysplasia. Endoscopic examination of the residual angiodysplasia was performed before and after valve replacement and there was no morphological change.