The purpose of this study is to determine whether 12-month prophylactic treatment with
pantoprazole is superior to 1-month therapy without major cardiovascular events (MACE)
increased significantly, in prevention of dual antiplatelet therapy (DAPT)-induced upper
gastrointestinal (GI) mucosal injury after coronary artery bypass graft (CABG) surgery. The
potentially serious harm of DAPT on gastroduodenal mucosa will be assessed by
esophagogastroduodenoscopy (EGD).