Diagnostic Validation of a High-Sensitivity Cardiac Troponin I Assay
Nils A. Sörensen, Alina Goßling, Franz–Josef Neumann, Tau Hartikainen, Paul M. Haller, Lea Scharlemann, Jonas Lehmacher, Andreas Ziegler, Stefan Blankenberg, Tanja Zeller, Gerhard Nordholt, Thomas Renné, Dirk Westermann
Abstract
BACKGROUND: Emergency departments worldwide are increasingly adopting rapid diagnosis of patients with suspected myocardial infarction (MI) based on high-sensitivity troponin. We set out to assess the diagnostic accuracy of a high-sensitivity cardiac troponin I (hs-cTnI) assay in a prospective study. METHODS: In a cohort study including 1800 patients presenting with suspected acute MI, we developed and temporally validated a 0/1 h diagnostic algorithm using the Siemens Atellica IM hs-cTnI assay. The algorithm was established in the first 928 patients and validated in the following 872 patients. RESULTS: The derived algorithm consisted of a baseline rule-out of non-ST-segment elevation MI using a cutoff <3 ng/L in patients with symptom onset ≥3 h or an admission troponin I level <6 ng/L with a Δ change of <3 ng/L from 0 h to 1 h. For rule-in, an admission troponin I level ≥120 ng/L or an increase within the first hour ≥12 ng/L was required. Application of the algorithm to the validation cohort showed a negative predictive value of 99.8% (95% CI, 98.7%-100.0%), sensitivity of 99.1% (95% CI, 95.1%-100.0%), and 48.3% of patients ruled out, whereas 15.1% were ruled in with a positive predictive value of 68.0% (95% CI, 59.1%-75.9%) and specificity of 94.4% (95% CI, 92.5%-96.0%). The diagnostic performance was comparable to guideline-recommended application of an established hs-cTnI assay in a rapid 0/1 h strategy. CONCLUSIONS: The Siemens hs-cTnI assay is well suited for application in rapid diagnostic stratification of patients with suspected MI. STUDY REGISTRATION: www.clinicaltrials.gov (NCT02355457).