The universal 2012 definition of myocardial infarction compared to the 2007 definition

Objectives: The third Universal 2012 definition of myocardial infarction (MI) has not been compared to the Universal 2007 definition with regard to the number of cases identified, classification and mortality.Design: We examined potential MI events according to the two universal definitions in 1494 patients admitted to the University hospital during the 12 months. Patients were included either because of an MI discharge diagnosis (815 patients) or due to elevated troponin I levels without an MI discharge diagnosis (679 patients).Results: Applying the Universal 2012 definition resulted in 760 of the 1494 patients suffering from MI, as compared to 769 according to the Universal 2007 definition. The lower number of MI events applying the 2012 definition was mainly explained by the stricter definition of Type 4a MI. The 760MI events were classified as Type 1 (685), 2 (27), 3 (28), 4a (13), 4b (3) and 5 (4).Conclusions: The application of the third Universal 2012 definition of MI instead of the Universal 2007 definition resulted in a 1% reduction of the total number of MIs. For a practical clinical purpose, the reduction was confined to patients with Type 4a MI. The change of definition had no impact on all-cause mortality.