Troponin concentrations for stratification of patients with acute coronarysyndromes in relation to therapeutic efficacy of tirofiban

Background A major challenge for physicians is to identify patients with ac ute coronary syndromes who may benefit from treatment with glycoprotein-IIb /IIIa-receptor antagonists. We investigated whether troponin concentrations can be used to stratify patients for benefit from treatment with tirofiban , Methods We enrolled 2222 patients of the Platelet Receptor Inhibition in Ischemic Syndrome Management study with coronary artery disease and who had had chest pain in the previous 24 h. All patients received aspirin and wer e randomly assigned treatment with tirofiban or heparin. We took baseline m easurements of troponin I and troponin T. We recorded death, myocardial inf arction, or recurrent ischaemia after 48 h infusion treatment and at 7 days and 30 days. Findings 629 (28.3%) patients had troponin I concentrations h igher than the diagnostic threshold of 1.0 mu g/L and 644 (29.0%) troponin T concentrations higher than 0.1 mu g/L. 30-day event rates (death, myocard ial infarction) were 13.0% for troponin-I-positive patients compared with 4 .9% for troponin-I-negative patients (p<0.001), and 13.7% compared wth 3.5% for troponin T (p<0.001). At 30 days, in troponin-I-positive patients, tir ofiban had lowered the risk of death (adjusted hazard ratio 0.25 [95% CI 0. 09-0.68], p=0.004) and myocardial infarction (0.37 [0.16-0.84], p=0.01). Th is benefit was seen in medically managed patients (0.30 [0.10-0.84], p=0.00 4) and those undergoing revascularisation (0.37 [0.15-0.93] p=0.02) after 4 8 h infusion treatment. By contrast, no treatment effect was seen for tropo nin-I-negative patients. Similar benefits were seen for troponin-I-positive patients. Interpretation Troponin I and troponin T reliably identified hig h-risk patients with acute coronary syndromes, managed medically and by rev ascularisation, who would benefit from tirofiban.