Lab Medicine Significance 7/10

New VITROS High-Sensitivity Troponin I Assay Matches Established hs-cTn Platforms in Clinical Validation

In 1,231 emergency department patients with suspected MI, the hs-cTnI-VITROS assay achieved an AUC of 0.95, comparable to hs-cTnT-Elecsys (0.94) and hs-cTnI-Architect (0.92). A derived 0/1-hour algorithm ruled out 53% of patients with 100% sensitivity and identified 14% for direct rule-in with 95.6% specificity, with a 99.8% 30-day survival rate among those ruled out. The study validates VITROS as a clinically equivalent option, expanding the ecosystem of available hs-cTn platforms.

The original study

Clinical Use of a New High-Sensitivity Cardiac Troponin I Assay in Patients with Suspected Myocardial Infarction.

Authors
Boeddinghaus J, Twerenbold R, Nestelberger T, Koechlin L, Wussler D, Meier M, et al.
Journal
Clinical chemistry
Type
Clinical Trial, Journal Article, Multicenter Study, Observational Study, Research Support, Non-U.S. Gov't
PMID
31570633
Read the original study →

Original abstract

BACKGROUND: We aimed to validate the clinical performance of the high-sensitivity cardiac troponin I [VITROS® Immunodiagnostic Products hs Troponin I (hs-cTnI-VITROS)] assay. METHODS: We enrolled patients presenting to the emergency department with symptoms suggestive of acute myocardial infarction (AMI). Final diagnoses were centrally adjudicated by 2 independent cardiologists considering all clinical information, including cardiac imaging: first, using serial hs-cTnT-Elecsys (primary analysis) and, second, using hs-cTnI-Architect (secondary analysis) measurements in addition to the clinically used (hs)-cTn. hs-cTnI-VITROS was measured at presentation and at 1 h in a blinded fashion. The primary objective was direct comparison of diagnostic accuracy as quantified by the area under the ROC curve (AUC) of hs-cTnI-VITROS vs hs-cTnT-Elecsys and hs-cTnI-Architect, and in a subgroup also hs-cTnI-Centaur and hs-cTnI-Access. Secondary objectives included the derivation and validation of an hs-cTnI-VITROS-0/1-h algorithm. RESULTS: AMI was the adjudicated final diagnosis in 158 of 1231 (13%) patients. At presentation, the AUC for hs-cTnI-VITROS was 0.95 (95% CI, 0.93-0.96); for hs-cTnT-Elecsys, 0.94 (95% CI, 0.92-0.95); and for hs-cTnI-Architect, 0.92 (95% CI, 0.90-0.94). AUCs for hs-cTnI-Centaur and hs-cTnI-Access were 0.95 (95% CI, 0.94-0.97). Applying the derived hs-cTnI-VITROS-0/1-h algorithm (derivation cohort n = 519) to the validation cohort (n = 520), 53% of patients were ruled out [sensitivity, 100% (95% CI, 94.1-100)] and 14% of patients were ruled in [specificity, 95.6% (95% CI, 93.4-97.2)]. Patients ruled out by the 0/1-h algorithm had a survival rate of 99.8% at 30 days. Findings were confirmed in the secondary analyses using the adjudication including serial measurements of hs-cTnI-Architect. CONCLUSIONS: The hs-cTnI-VITROS assay has at least comparable diagnostic accuracy with the currently best validated hs-cTnT and hs-cTnI assays. CLINICALTRIALSGOV IDENTIFIER: NCT00470587.