Chronic myocardial injury diagnosis according to hs-cTnT identified 3.9-4.5 times more patients (n=207) than hs-cTnI assays (n=46-53) and had higher prognostic accuracy for mortality or CV events.
Cohort (n=1,292)
Does the choice of high-sensitivity cardiac troponin assay affect the prevalence and prognostic accuracy of chronic myocardial injury diagnosis in patients with suspected acute coronary syndrome?
The prevalence of chronic myocardial injury is highly assay-dependent, with cTnT diagnosing significantly more patients and offering higher prognostic accuracy at the 99th percentile URL compared to cTnI assays.
OBJECTIVES: Chronic myocardial injury (CMI) is defined as stable concentrations of cardiac troponin T or I (cTnT or cTnI) above the assay-specific 99th percentile upper reference limit (URL) and signals poor outcome. The clinical implications of diagnosing CMI are unclear. We aimed to assess prevalence and association of CMI with long-term prognosis using three different high-sensitivity cTn (hs-cTn) assays. METHODS: A total of 1,292 hospitalized patients without acute myocardial injury had cTn concentrations quantified by hs-cTn assays by Roche Diagnostics, Abbott Diagnostics and Siemens Healthineers. The median follow-up time was 4.1 years. The prevalence of CMI and hazard ratios for mortality and cardiovascular (CV) events were calculated based on the URL provided by the manufacturers and compared to the prognostic accuracy when lower percentiles of cTn (97.5, 95 or 90), limit of detection or the estimated bioequivalent concentrations between assays were used as cutoff values. RESULTS: There was no major difference in prognostic accuracy between cTnT and cTnI analyzed as continuous variables. The correlation between cTnT and cTnI was high (r=0.724-0.785), but the cTnT assay diagnosed 3.9-4.5 times more patients with having CMI based on the sex-specific URLs (TnT, n=207; TnI Abbott, n=46, TnI Siemens, n=53) and had higher clinical sensitivity and AUC at the URL. CONCLUSIONS: The prevalence of CMI is highly assay-dependent. cTnT and cTnI have similar prognostic accuracy for mortality or CV events when measured as continuous variables. However, a CMI diagnosis according to cTnT has higher prognostic accuracy compared to a CMI diagnosis according to cTnI.
Steiro et al. (Wed,) conducted a cohort in Suspected acute coronary syndrome without acute myocardial injury (n=1,292). High-sensitivity cardiac troponin T (hs-cTnT) assay vs. High-sensitivity cardiac troponin I (hs-cTnI) assays (Abbott and Siemens) was evaluated on Mortality and cardiovascular (CV) events. Chronic myocardial injury diagnosis according to hs-cTnT identified 3.9-4.5 times more patients (n=207) than hs-cTnI assays (n=46-53) and had higher prognostic accuracy for mortality or CV events.