0/2 h-Algorithm for Rapid Triage of Suspected Myocardial Infarction Using a Novel High-Sensitivity Cardiac Troponin I Assay
Karin Wildi, Jasper Boeddinghaus, Thomas Nestelberger, Pedro López‐Ayala, Ana Yufera Sanchez, Bernhard Okamura, Samyut Shrestha, J.-J Rohner, Òscar Miró, Gemma Martínez‐Nadal, Francisco Javier Martín‐Sánchez, Luca Koechlin, Raphael Twerenbold, Michael Christ, Damian Kawecki, María Rubini Giménez, Dagmar I. Keller, Christian Mueller, for the APACE investigators, Desirée Wussler, Ivo Strebel, Adam Bakula, Simon Frey, Danielle M Gualandro, Tobias Zimmermann, Christian Puelacher, Jeanne du Fay de Lavallaz, Eliška Potluková, Matthias Diebold, Nicolas Geigy, Katharina Rentsch, Sandra Mitrović, Carolina Fuenzalida, Noemi Glarner, Beata Morawiec, Tobias Breidthardt, Michael Freese, Beatriz López, Sofia Calderón, Esther Rodríguez Adrada, Eva Ganovská, Jiri Parenica, Arnold von Eckardstein, Isabel Campodarve, Joaquim Gea
Abstract
BACKGROUND: We aimed to derive and validate a 0/2 h-algorithm using the new high-sensitivity cardiac troponin I (hs-cTnI)-VITROS assay (VITROS® Immunodiagnostic Products hs-Troponin I Reagent Pack, Ortho Clinical Diagnostics) for rapid rule-out/in of non-ST-segment elevation myocardial infarction (NSTEMI). METHODS: The final diagnosis was centrally adjudicated by 2 independent cardiologists according to the fourth universal definition of myocardial infarction (MI) among 1888 patients presenting to the emergency department with acute chest pain. hs-cTnI-VITROS concentrations were measured at presentation and at 2 h in a blinded fashion. The optimal assay-specific thresholds for the hs-cTnI-VITROS 0/2 h-algorithm were derived in a randomly selected 70% of the cohort and validated in the remaining 30%. RESULTS: NSTEMI was the final diagnosis in 216/1322 (16.3%) patients of the derivation cohort. Rule-out was defined as baseline hs-cTnI concentrations of <1 ng/L in patients presenting with chest pain onset >3 h or a baseline hs-cTnI concentration of <2 ng/L and an absolute change of <3 ng/L within 2 h. Thresholds for rule-in were either ≥40 ng/L at presentation or an absolute change within 2 h of ≥ 5ng/L. In the derivation cohort, these thresholds ruled-out 50.8% of patients with a negative predictive value (NPV) and sensitivity of 99.7% (95% Confidence Interval (CI), 98.8-99.9%) and 99.1% (95% CI, 96.7-99.9%), and ruled-in 17.9% with a positive predictive value (PPV) of 79.2% (95% CI, 74.3-83.5%). In the validation cohort, NSTEMI was the final diagnosis in 91/566 (16.1%) patients. The derived 0/2 h-algorithm ruled-out 46.3% of patients with a NPV and sensitivity of 100% (95% CI, 95.6-100%) and 100% (95% CI, 96.0-100%), and ruled-in 18.9% with a PPV of 73.8% (95% CI, 66.1-80.3%) in the validation cohort. CONCLUSION: hs-cTnI-VITROS concentrations at presentation combined with absolute changes within the first 2 h allowed safe rule-out and accurate rule-in of NSTEMI in two-thirds of unselected patients presenting with acute chest pain to the emergency department. TRIAL REGISTRATION: www.clinicaltrials.gov: NCT0047058.