A-011 Single High-Sensitivity Cardiac Troponin I Compared to High-Sensitivity Cardiac Troponin T Measurement to Rule Out Acute Myocardial Infarction at Low Risk for 30-Day Adverse Events: CONTRAST Study

Abstract Background Cardiac troponin (cTn) is the preferred biomarker for diagnosing myocardial injury and acute myocardial infarction (MI). There are few comparative studies addressing the clinical performance of high-sensitivity (hs)-cTnI and hs-cTnT assays using fresh plasma for early rule out of myocardial infarction (MI) on presentation in patients presenting to emergency departments (ED). This study examined the performance strategies of a derived optimal concentration for a single high-sensitivity cardiac troponin I (hs-cTnI) measurement compared to a derived optimal concentration for a single high-sensitivity cardiac troponin T (hs-cTnT) measurement to rule out acute MI. Methods The COmparisoN of high-sensitivity cardiac TRoponin I and T ASsays Trial (CONTRAST) (NCT03214029) is a prospective, observational cohort study of consecutive adult ED patients (n = 2208) undergoing serial cTn measurements as clinically indicated. hs-cTnI (Abbott ARCHITECT) and hs-cTnT (Gen 5, Roche e601) measurements using fresh EDTA plasma were obtained. We determine optimal hs-cTn cutoffs for negative predictive value (NPV) and sensitivity for the diagnosis of acute MI (type 1 and type 2) to allow for a maximum number for early discharges with minimal risk of adverse events (acute MI or cardiac death) at 30 days. Results Acute MI occurred in 161 patients (7.3%), including 68 (42.2%) type 1 MI and 93 (57.7%) type 2 MI. For hs-cTnI (<2 ng/L) optimal NPV and sensitivity for adverse events were 99.1% (95% confidence interval 97.7%-99.8%) and 98.2% (CI. 95.4-99.5%). 450 Patients (21%) qualified for early rule out, at a 1.8% miss rate at 30 days. For hs-cTnT (<6 ng/L) optimal NPV and sensitivity for adverse events were 99.2% (CI 98.0%-99.8%) and 98.1% (CI. 95.3-99.5%). 513 Patients (24%) qualified for early rule out, at a 1.9% miss rate at 30 days. Conclusions In CONTRAST, a strategy using a single sample hs-cTnI or hs-cTnT alone allows for the early identification of patients unlikely to have acute MI and who are at very low risk for adverse events at 30 days. Minor differences existed between the Abbott ARCHITECT hs-cTnI assay and the Roche e601 hs-cTnT (Gen 5) assay in fresh plasma were found.