Multisite study of a second generation whole blood rapid assay for cardiactroponin T

We evaluated a second generation, qualitative, whole blood rapid assay for cardiac troponin T (cTnT), which employs a more cardio-specific troponin T mouse monoclonal capture antibody. Using quantitative cTnT enzyme-linked im munosorbent assay (ELISA) results as the benchmark for accuracy, we compare d the performance of the second generation and the original whole blood rap id assays in 445 samples from patients with the following diagnoses, determ ined by medical record review: myocardial infarction, coronary bypass surge ry, ischaemic heart disease, musculoskeletal disease, renal failure or othe r noncardiac conditions. Overall, concordance between the second generation cTnT Rapid Assay(TM) and the quantitative cTnT ELISA, compared using the M cNemar test and a cut-off concentration of 0.1 mu g/L, was in the range 76- 94% for each patient group. Using a receiver operating characteristic plot, the cut-off for the second generation cTnT Rapid Assay was in the range 0. 06-0.08 mu g/L. We conclude that the second generation cTnT whole blood ass ay has a 2.5-fold lower analytical cut-off than the original rapid assay (0 .2 mu g/L) and may represent a more sensitive clinical tool for the rapid t riage and risk stratification of cardiac patients.