Use of Abbott High Sensitivity Troponin I Assay In Acute Coronary Syndromes

Hypothesis: High sensitivity cTnI assays will have improved diagnostic accuracy for type 1 MI compared to contemporary cTnI assays. The primary objective of the study is to determine the performance of a high sensitivity cardiac troponin I (hs-cTnI) assay compared to a contemporary cTnI assay for the diagnostic accuracy of type 1 acute myocardial infarction (AMI). The diagnostic performance of Abbott's hs-cTnI assay will be evaluated. Investigators will assess the assay's ability to diagnose AMI earlier and to rule out AMI earlier. The sensitivity, specificity, positive predictive value and negative predictive value of the hs-cTnI assay will be evaluated with both a universal cut off as well as with gender and potentially age derived 99th percentile upper reference limits (URL). Investigators will evaluate delta hs-cTnI values (pre-specified absolute concentration and percent changes over time) for their ability to contribute to the negative predictive value and hence potentially lead to an earlier rule out of AMI (improved specificity). Additionally, investigators will assess delta changes of the hs-cTnI assay for their potential contribution to the clinical differentiation of type 1 and type 2 (supply demand mismatch) MIs. Lastly, investigators will compare the diagnosis of AMI based on the currently used contemporary assay to the hs-assay, to assess both the incidence of AMI as well as for the time to diagnosis.