Concurrent evaluation of novel cardiac biomarkers in acute coronary syndrome: myeloperoxidase and soluble CD40 ligand and the risk of recurrent ischaemic events in TACTICS-TIMI 18.

AIMS We investigated the prognostic performance of myeloperoxidase (MPO), and soluble CD40 ligand (sCD40L) along with B-type natriuretic peptide (BNP), high-sensitivity C-reactive protein (hsCRP), and cardiac troponin I (cTnI) for non-fatal recurrent ischaemic events in non-ST elevation acute coronary syndrome (ACS). METHODS AND RESULTS We measured plasma MPO and sCD40L in 1524 patients with ACS treated with tirofiban and randomized to early invasive vs. conservative management in the TACTICS-TIMI 18 trial who survived to 180 days. Patients with elevated baseline MPO (>884 pM) were at higher risk of non-fatal myocardial infarction or rehospitalization for ACS at 30 days (9.3 vs. 4.6%, P < 0.001). In contrast, no difference was observed with higher sCD40L (>989 pg/mL, 7.6 vs. 6.3%, P = 0.31). MPO remained associated with recurrent ischaemic events after adjustment for age, ST-deviation, diabetes, prior coronary artery disease, heart failure, cTnI, hsCRP, and sCD40L (OR 2.10; 95% CI 1.36-3.23, P = 0.001). This association was attenuated by 180 days (OR 1.26; 0.95-1.68). Stratification using baseline MPO, BNP, and cTnI identified a >3-fold gradient of risk. CONCLUSION MPO adds to BNP and cTnI for short-term risk assessment for recurrent ischaemic events in non-ST elevation ACS. sCD40L was not associated with risk in this population treated with a platelet GPIIb/IIIa receptor antagonist.