The Changing Profile of Myocardial Infarction

In August 2000, the biomarker component of the diagnostic criteria for myocardial infarction (MI) changed from creatine kinase-MB (CK-MB) to troponin, complicating efforts to track trends in MI incidence, severity, and outcomes. Fortunately, data gathered for decades in Olmsted County, Minnesota, make the task feasible.

From 1987 through 2006, 2816 patients in that region (43%women; 39% aged ≥75) were hospitalized for MI. Of the 1127 MIs that occurred after August 2000, 25% met the troponin but not the CK-MB criteria. Patients whose MIs met only the troponin criteria were older, were more likely to be female, and had more comorbidities than those whose MIs met the CK-MB criteria.

When both CK-MB–diagnosed and troponin-diagnosed MIs were count…