New global standard set for heart attack blood test interpretation

<p>Background Measurement of cardiac troponin (cTn) using high-sensitivity assays is recommended for the diagnosis of myocardial infarction. We determined sex-specific and uniform 99th percentile upper reference limits (URLs) using the new Elecsys (R) Troponin T high-sensitivity Gen 6 assay in a global, healthy reference range cohort.Methods Lithium-heparin plasma and serum samples were prospectively collected from apparently healthy individuals aged &gt;= 20 years across 34 global sites in the United States, Europe, China, and Japan. cTnT was measured using the Troponin T high-sensitivity Gen 6 assay on the Cobas (R) e 801 analyzer. Exclusion criteria were defined according to the 2022 IFCC guidance. Uniform and sex-specific 99th percentile URLs and nonparametric 95% CIs were determined in plasma and serum separately and combined.Results The final study population comprised 4147 participants (52.5% female) with a median (25th-75th percentiles) age of 48.0 (33.0-59.0) years; 45.8%, 47.9%, 5.2%, and 1.1% were White, Asian, Black, and other/unknown, respectively. For sample matrices combined (n = 8294), 81.0% and 99.2% of cTnT values were above the limit of detection in females and males, respectively. Sex-specific 99th percentile URLs (95% CI) were 18 (16-23) ng/L for females and 32 (28-35) ng/L for males; the uniform 99th percentile URL was 27 (24-31) ng/L. URLs were comparable in plasma and serum samples.Conclusions This study determined sex-specific and uniform 99th percentile URLs for the Troponin T high-sensitivity Gen 6 assay that were comparable irrespective of the matrix used in a large, global, healthy reference population.</p>