Guidelines for the diagnosis and management of unstable angina and non-Q-wave myocardial infarction: Proposed revisions

Background In 1994, the United States Agency for Health Care Policy and Research issued clinical practice guidelines for the diagnosis and management of unstable angina and non-Q-wave myocardial infarction. In the past 5 years, rapid progress has been made in the management of patients with unstable coronary syndromes, yet current guidelines do not necessarily reflect these advances. Methods and Results An international forum of cardiology investigators reviewed existing guidelines and discussed areas in which the diagnosis and treatment of unstable angina and non-Q-wave myocardial infarction should be modified. It was agreed that there is sufficient evidence to recommend the following changes: (1) use of serum cardiac markers should be expanded to include troponin I and T levels as diagnostic and prognostic tools; (2) low-molecular-weight heparins should replace unfractionated heparin as antithrombotic agents; (3) new classes of antiplatelet agents are recommended in addition to aspirin; and (4) the use of cholesterol-lowering drugs is appropriate in the long-term management of these patients. Conclusions Evidence from clinical trials within the last 5 years requires that significant changes be made to existing guidelines for the diagnosis and management of unstable angina and non-Q-wave myocardial infarction. The recommendations detailed should be considered in the creation and implementation of updated guidelines.