Abstract 18549: High-sensitivity Troponin I in Stable Patients With Atherosclerotic Disease in the TRA2°P- TIMI 50 Trial

Abstract

Background: Cardiac troponin I, measured with a high-sensitivity assay (hsTnI), is a well-established prognosticator in patients with acute coronary syndromes. However, its prognostic role in patients with stable atherosclerotic disease, particularly with respect to new or recurrent myocardial infarction (MI), is less defined. Methods: We measured hsTnI (Abbott ARCHITECT) in 19,429 patients with prior MI, ischemic stroke, or symptomatic peripheral arterial disease, who had available baseline samples in the TRA 2°P-TIMI 50 trial of the platelet inhibitor vorapaxar vs. placebo. hsTnI concentration was categorized into 5 groups based on the detection limit (1.9 ng/L), the 99th percentile reference limit (26 ng/L), and tertiles in between (1.9-26 ng/L). The median follow-up was 2.5 years. Sensitivity analyses excluded patients with a history of MI in the prior 30 days and tested sex-specific cutpoints. Results: Higher baseline hsTnI levels were associated with older age, male sex, and an increased burden of atherosclerotic disease. hsTnI identified a graded risk of cardiovascular (CV) death, MI, or stroke with a consistent pattern across each element of this composite, in particular CV death and MI (Figure). This risk relationship was independent of established clinical risk indicators, B-type natriuretic peptide and C-reactive protein (adj-HR 2.17, 95% CI 1.61-2.92 for hsTnI >26 ng/L) and was consistent after excluding pts with recent MI (adj-HR 2.69, 95% CI 1.95-3.71 for hsTnI >26 ng/L). There were no meaningful differences using sex-specific hsTnI cutpoints. The interaction with efficacy of vorapaxar vs. placebo according to hsTnI will be presented. Conclusion: When measured in stable patients with established atherosclerosis, hsTnI concentrations, even below the 99th percentile reference limit, effectively stratified the risk of new or recurrent MI.