Diagnosis of Non-ST-Elevation Myocardial Infarction (NSTEMI)

The third version of universal definition of myocardial infarction (MI) from 2012 defines acute myocardial infarction (MI) by evidence of myocardial necrosis in a clinical setting of acute myocardial ischemia. Diagnostic criteria include a rise and/or fall of serially tested cardiac biomarkers (preferentially cardiac troponins) with at least one value > 99th percentile of URL combined with ischemic symptoms, new electrocardiogram (ECG) changes, imaging evidence of new loss of viable myocardium or new regional wall-motion abnormalities, or identification of intracoronary thrombus by angiography or autopsy. This article summarizes the MI definition and strategies for “rule in” and “rule out” of MI.