Colonic angiodysplasia (arteriovenous malformation) describes the development of dilated, tortuous submucosal vessels and is a common cause of hematochezia. However, DB is more likely in this patient with a history of diverticulosis and no predisposing risk factors for colonic angiodysplasia (eg, end-stage kidney disease, von Willebrand disease, aortic stenosis).