Analytical performance of a sensitive assay for cardiac troponin I with loci technology.

Objectives: To confirm the analytical performance of the Dimension Vista LOCI troponin I assay (cTnI).

Design And Method: Limit of blank (LoB), limit of detection (LoD), limit of quantitation (LoQ) with a 10% coefficient of variation (CV), linearity, precision, method comparison, and 99th percentile upper reference limits (URL) were analyzed. Endogenous analytes and rheumatoid factor (RF) were tested for assay interference.

Results: The 99th percentile was 0.022 microg/L (CV=14%) and the LoQ was 0.036 microg/L. The ratio of 10% CV concentration to 99th percentile was 1.63. Linearity extended from 0 to 44.36 microg/L. The method comparison equation was Dimension(R) Vista=0.94 (Dimension RxL)+0.00 microg/L with bias at low levels. No interference was detected.

Conclusions: This study shows acceptable performance characteristics of the LOCI cTnI assay on Dimension Vista to diagnosis and risk stratification of patients with acute coronary syndrome symptoms.