Benefit of glycoprotein IIb/IIIa inhibition in patients with acute coronary syndromes and troponin T-positive status - The PARAGON-B troponin T substudy

Background-Troponin T (TnT) is valuable for short- and long-term risk strat ification of patients with acute coronary syndromes (ACS), It also may pred ict which ACS patients will benefit from glycoprotein (GP) IIb/IIIa blockad e. Methods and Results-We prospectively studied 1160 patients with non-ST-segm ent elevation ACS randomized in PARAGON-B to receive lamifiban, an intraven ous GP IIb/IIIa antagonist, or placebo. TnT levels were obtained before stu dy treatment began and 24 to 72 hours later; assays were performed by a bli nded core laboratory. At baseline, 40.2% of patients were TnT-positive (gre ater than or equal to0.1 ng/mL); these patients were older and more often m ale or smokers. Patients positive at baseline had a significantly higher ra te of the primary end point (composite of death, myocardial [re]infarction, or severe recurrent ischemia at 30 days, odds ratio, 1.5; 95% CI, 1.1 to 2 .1) than those who were TnT-negative. Lamifiban was associated with signifi cant reduction in the primary end point (from 19.4% to 11.0%, P=0.01) among TnT-positive patients but not among TnT-negative patients (11.2% for place bo versus 10.8% for lamifiban, P=0.86; P=0.08 for test of interaction betwe en TnT status and treatment assignment). This pattern held for the end poin ts of death alone and death or myocardial (re)infarction at 30 days. Peak T nT level at 48 hours did not differ with lamifiban treatment. Conclusions-TnT predicts poor short-term outcomes in non-ST-segment elevati on ACS. Treatment benefit with lamifiban is limited almost exclusively to T nT-positive patients, reducing 30-day adverse outcomes to a rate nearly ide ntical to that of negative patients.