A 64-year-old man presents to your primary care office because his ‘pre-surgery clearance form’ needs to be filled by a doctor. Next month he is scheduled to undergo pancreatectomy for a malignant tumor of the pancreatic head. His medical history is significant for ischemic heart disease and diabetes mellitus requiring insulin. His most recent serum creatinine level was 2.1 mg/dL. Of the following which medication is considered the first-line therapy to reduce perioperative morbidity and mortality in this patient?
