1 The Faculty of Medicine, Aalborg University, VBN2 Klinik Hjerte-Lunge, The Faculty of Medicine, Aalborg University, VBN3 Hjertemedicin (Kardiologi), The Faculty of Medicine, Aalborg University, VBN4 Aalborg University Hospital, The Faculty of Medicine, Aalborg University, VBN5 Department of Cardiology B, Odense University Hospital, Odense, Denmark.6 Kardiologi7 Department of Anesthesiology and Intensive Care, Odense University Hospital, Odense, Denmark.8 Department of Nuclear Medicine, Odense University Hospital and Centre of Health Economics Research, University of Southern Denmark, Odense, Denmark.9 Department of Clinical Pharmacology, University of Southern Denmark, Odense, Denmark.10 Department of Cardiology, Aarhus University Hospital, Aarhus, Denmark.
Observations from an unselected hospital cohort
BACKGROUND: The classification of myocardial infarction into 5 types was introduced in 2007. The prognostic impact of this universal definition, with particular focus on type 2 myocardial infarction, has not been studied prospectively in unselected hospital patients. METHODS: During a 1-year period, all hospitalized patients having cardiac troponin I measured were considered. The diagnosis of a myocardial infarction was according to the universal definition, and specified criteria were used in the classification of type 2 myocardial infarction. Follow-up was at least 1 year, with mortality as the end point. RESULTS: A total of 3762 consecutive patients were studied, of whom 488 (13%) had a myocardial infarction. In 119 patients a type 2 myocardial infarction was diagnosed. After a median of 2.1 years (interquartile range, 1.6-2.5 years), 150 patients had died, with a mortality rate of 49% (58/119) in those with type 2 myocardial infarction and 26% (92/360) in those with type 1 myocardial infarction (P < .0001). In a multivariable Cox regression analysis the following variables were independently associated with mortality: current or prior smoker, high age, prior myocardial infarction, type 2 myocardial infarction, hypercholesterolemia, high p-creatinine, and diabetes mellitus. The multivariable-adjusted hazard ratio for type 2 myocardial infarction was 2.0 (95% confidence interval, 1.3-3.0). With shock as the only exception, mortality was independent of the triggering conditions leading to type 2 myocardial infarction. CONCLUSIONS: Mortality in patients with type 2 myocardial infarction is high, reaching approximately 50% after 2 years. Further descriptive and survival studies are needed to improve the scientific evidence on which treatment of type 2 myocardial infarction is based.
American Journal of Medicine, 2014, Vol 127, Issue 4, p. 295-302