Gallacher PJ, Miller-Hodges E, Shah ASV, et al. - Researchers described the effects of the implementation of high-sensitivity cardiac troponin (hs-cTn) testing among patients with kidney impairment.

• A stepped-wedge, cluster-randomized clinical trial, named High-Sensitivity Troponin in the Evaluation of Patients With Acute Coronary Syndrome (High-STEACS), was conducted to examine the utility of a hs-cTnI assay in consecutive patients with suspected acute coronary syndrome.

• Contemporary and high-sensitivity assays (ARCHITECTSTAT; Abbott Laboratories) were used to perform measurement of cTnI.

• Before use, the contemporary assay (single threshold based on the coefficient of variation) guided care and findings from the hs-cTnI assay were suppressed.

• Random assignment of sites was then done to early or late use of hs-cTnI testing, for which there was suppression of results from the contemporary assay and care was guided by the hs-cTnI assay with gender-specific 99th percentile diagnostic thresholds.

• Elevations in hs-cTnI concentrations was evident in 10,111 of 46,927 patients (22%; mean [SD] age, 71 [15] years; 4,853 women [48%]) across both phases, of whom 4,220 (42%) had kidney impairment.

• There was 6-fold increase in the frequency of elevated hs-cTnI concentrations in correlation with a declination in kidney function from an eGFR of 90 or greater to less than 30 mL/min/1.73 m², along with this there was halving of the proportion attributable to type 1 myocardial infarction.

• Despite the effectiveness of hs-cTnI at enabling the early rule out of myocardial infarction in patients with kidney impairment, patients with elevated levels show no improvement in outcomes with its use; this was observed regardless of presence of kidney impairment.