Association Between Minor Elevations of Creatine Kinase-MB Level and Mortality in Patients With Acute Coronary Syndromes Without ST-Segment Elevation

THE CRITERIA USED TO DIAGnose myocardial infarction (MI) are important both clinically and in clinical trials. The most widely accepted diagnostic criteria for MI are those of the World Health Organization, first proposed almost 20 years ago. These criteria require presence of at least 2 of the following 3 elements to diagnose MI: (1) a history of ischemic-type chest discomfort, (2) evolutionary changes on serial electrocardiograms, and (3) a rise and fall in serum cardiac enzymes. Today, the cornerstone of these diagnostic criteria is evaluation of serial cardiac markers. The most commonly used markers, both clinically and in clinical research, are creatine kinase (CK) and Author Affiliations: Duke Clinical Research Institute, Durham, NC (Drs Alexander, Mahaffey, Newby, Ohman, Califf, and Harrington, and Mr Sparapani); Cardialysis, Rotterdam, the Netherlands (Drs Deckers and Simoons); Universidad Católica, Santiago, Chile (Dr Corbalán); Ospedale San Raffaele, Milan, Italy (Dr Chierchia); Hopital de la Citadelle, Liege, Belgium (Dr Boland); and the Cleveland Clinic Foundation, Cleveland, Ohio (Dr Topol). A list of the names of members of the PURSUIT Steering Committee has been published (N Engl J Med. 1998;338:436-443). Corresponding Author and Reprints: John H. Alexander, MD, Duke Clinical Research Institute, PO Box 17969, Durham, NC 27715 (e-mail: alexa017 @mc.duke.edu). Context Controversy surrounds the diagnostic and prognostic importance of slightly elevated cardiac markers in patients with acute coronary syndromes without STsegment elevation.