14 Differential microparticle signature in acute coronary syndromes and stable angina

Background Microparticles (MP) are sub-micron vesicles shed from eukaryotic cells following activation or apoptosis. They appear to have a role in the genesis and progression of atherosclerosis, leading to symptomatic coronary artery disease (CAD). It is now established that the levels of MP are elevated in CAD however, the MP signature associated with the spectrum of CAD is yet to be established. Methods 42 patients undergoing PCI (11 STEMI, 13 NSTEMI and 18 stable angina) were prospectively enrolled. MP levels from venous blood taken prior to PCI were measured by flow cytometry. Results (Figure 1): Patients with STEMI expressed significantly higher levels of CD62P+ platelet-derived MP (median 14.5%, IQR 8.1–20.3%) compared to NSTEMI (median 1.2%, IQR 0.4–19%, p + (ICAM-1) endothelial cell-derived MP. Conclusions The MP signature associated with CAD appears to differ with STEMI showing a predominantly pro-thrombotic signal and NSTEMI a pro-inflammatory signal. This suggests not only differing underlying pathophysiology but also indicated a potential new tool in rapid assessment and risk stratification.