"The process of guideline development for management of patients with acute myocardial infarction (AMI) has undergone substantial evolution since the inaugural publication entitled “Guidelines for the Early Management of Patients with Acute Myocardial Infarction” in 1990 under the auspices of the ACC/AHA Task Force on Assessment of Diagnostic and Therapeutic Cardiovascular Procedures (Chairman, Dr. Rolf Gunnar; Figure 1) (1). Subsequently, the ACC/AHA Task Force on Practice Guidelines convened a committee (Chairman, Dr. Thomas J. Ryan) in 1994 to revise the 1990 guidelines. In the 1996 guideline publication, “ACC/AHA Guidelines for the Management of Patients with Acute Myocardial Infarction,” the term acute coronary syndrome was used, reflecting the emerging overarching concept that disruption of a vulnerable or high-risk plaque causes an episode of ischemic discomfort (2). Emphasis was placed on the 12-lead electrocardiogram (ECG) that was used to categorize patients into 2 broad cohorts: those presenting with ST elevation and those presenting without ST elevation (ultimately diagnosed as unstable angina or non–Q-wave myocardial infarction (MI) depending on whether a biomarker of necrosis was detected in the patient’s blood). The 1996 guidelines discussed the management of both the ST-elevation and non–ST-elevation presentations of the acute coronary syndromes. The same approach was taken in the 1999 update of the guideline (also chaired by Dr. Ryan) that was posted as an electronic update on the ACC and AHAWorld Wide Web sites (3)."