Abstract 16746: Single High-Sensitivity Cardiac Troponin I Measurement Using the Siemens Atellica IM Assay to Rule-Out Acute Myocardial Infarction at Presentation in Low Risk in Patients Evaluated in the Emergency Department

Abstract

Introduction: High sensitivity cardiac troponin (hs-cTn) assays are able to quantitate low concentrations of cTn and provide an opportunity to rule out acute myocardial infarction (MI) at an early stage following a patient’s presentation to an emergency department. Hypothesis: The objectives of the current study were to examine the performance of single hs-cTnI measurement strategy to rule out acute MI and predict 30-day safety outcomes at presentation in these patients. Methods: This was a prospective, observational study of patients (n = 2342) presenting to US emergency departments with suspected acute coronary syndrome in whom cTnI measurements were obtained using the Siemens Atellica IM High Sensitivity Troponin I Assay (Siemens Healthcare Diagnostics). Clinical data and hs-cTnI results were analyzed to determine: 1) clinical sensitivity and negative predictive value (NPV) for ruling out acute MI and 2) safety outcomes of acute MI and death at 30 days, using the hs-cTnI limit of detection (LoD) 1.6 ng/L concentration. Results: Acute MI occurred in 306 patients (13.1%). In patients with a hs-cTnI <LoD (n=421, 18.0%), the clinical sensitivity and negative predictive value (NPV) for acute MI were 100% (95% CI 99.0,100) and 100% (CI 99.3,100), respectively. Further, the sensitivity and NPV for the safety outcome of acute MI or death within 30 days for hs-cTnI <LoD were 99.4% (CI 98.5, 99.9) and 99.5% (CI 98.9, 99.9), respectively. Only 2 patients (0.85%) had an event. Conclusion: A strategy of using a single hs-cTnI <LoD at presentation allowed the immediate identification of 18.0% of patients highly unlikely to have acute MI and who were at very low risk for events at 30 days. Additional studies to understand the clinical utility and cost-savings of this strategy are needed.