Of the 25 million patients who undergo noncardiac surgery in the United States each year, approximately three million have or are at risk of having coronary artery disease. Despite advances in the diagnosis and therapy of coronary artery disease, approximately 50,000 of these patients have a perioperative myocardial infarction, and more than half of the 40,000 deaths after surgery are caused by cardiac events. For perioperative myocardial infarction alone, health care costs exceeded $500 million per year in the 1980s. Determining the risk factors for adverse postoperative cardiac outcomes allowed the development of preventive strategies and the efficient allocation of health care resources.