Angiotensin-converting enzyme inhibitors have been shown to prolong survival and decrease infarct size in patients after acute coronary syndromes. Now there is evidence to suggest that angiotensin-converting enzyme inhibition is beneficial in coronary artery bypass patients. This review will summarize the beneficial effects of angiotensin-converting enzyme inhibition in patients with ischemic heart disease and provide evidence to show that the routine use of angiotensin-converting enzyme inhibition in coronary artery bypass patients can improve clinical outcomes.