Abstract 3731: Beta2-Integrin Activation on T-cell Subsets is an Independent Prognostic Factor in Patients with Unstable Angina Pectoris
Cardiac troponins provide excellent risk stratification in unstable angina (UA), but no reliable markers are available in troponin-negative patients. Beta2-integrin mediated T cell recruitment plays a pivotal role in coronary atherosclerotic plaque rupture. The present study investigates beta2-integrin activation on T cell subsets as a risk marker in UA. Functional activation (affinity/avidity) of beta2-integrins on T cells was measured using a flow cytometry-based whole blood assay in 87 patients with UA. Beta2-integrin activation was significantly higher in patients with severe coronary artery disease (sC) and myocardial infarction (MI) compared to patients with no/minimal coronary atherosclerosis (no/mC), irrespective of troponin status. Adjusted for cardiovascular risk factors, medication, left ventricular function, MI at enrollment and high sensitivity C-reactive protein (hsCRP), beta2-integrin activation was independently associated with incidence of revascularization, hospitalization and all major cardiovascular events during 9 months of follow-up after index investigation. The highest prognostic value of beta2-integrin activation was seen in troponin-and hsCRP-negative patients. Quantitative assessment of T cell beta2-integrin activation allows to identify high risk patients with UA and sC without established MI; furthermore, it is associated with incidence of future cardiovascular events independent of conventional risk factors (troponin, hsCRP).