Background: Current hospital practice involves protracted observation of chest-pain patients to rule out myocardial infarction. Concurrent measurement of multiple biomarkers may increase sensitivity and make rapid diagnosis feasible.
Objective: We sought to determine the optimal biomarker strategy for highly sensitive, early diagnosis of myocardial injury.
Study Design: A prospective evaluation of 171 acute coronary syndrome patients admitted to a single university medical center was performed. Blood tests for creatine kinase (CK), CK myocardial band isoenzyme (CK-MB), and troponin T were obtained at 0, 3, 6, 8, and 16 hours after presentation to the emergency department. Myocardial injury was defined as a troponin T level of ≥0.03 ng/mL.
Results: Troponin T had sensitivities of 79.7%, 95.7%, and 98.4% at the time of initial presentation, 3 and 6 hours after presentation, respectively. Using a combination of troponin T and CK-MB relative index, sensitivity on presentation was increased to 90.6%. The sensitivity was improved to 97.9% and 100% at 3 and 6 hours, respectively.
Conclusion: This study demonstrates that the diagnosis of myocardial injury can be accurately excluded within 6 hours of admission with high sensitivity using troponin T. The combination of troponin T and CK-MB relative index provided the largest improvement in diagnostic sensitivity at patient arrival. These results support the feasibility of rapid, efficient triage for the emergent presentation of patients with chest pain.
This study was supported by an unrestricted grant from Merck & Co., Inc. The sponsor had no role in the design of the study, performance of the research, or writing of the manuscript. The authors have no conflicts of interest that are directly relevant to the content of this study.
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