Microparticles in acute coronary syndrome.

BACKGROUND

Emerging evidence supports the role of cell-derived microparticles (MPs) in the pathophysiology of acute coronary syndrome (ACS).

OBJECTIVES

To explore the relationship between coronary and systemic MP levels, investigate the correlation between MPs, inflammatory markers and Troponin T in patients with ACS.

METHODS

Thirty seven patients with ACS scheduled for percutaneous coronary interventions (PCI) were studied. Eleven patients with stable angina (SA) were included as a control group. AnnexinV+MPs (AnV+MPs) and activated platelet-monocyte aggregates (PMA) from right atrium (RA) and culprit coronary artery (CO) distal to culprit lesion were measured using flow cytometry. High sensitivity C-reactive protein (CRP), Interleukin - 6 (IL-6), tumour necrosis factor - α (TNF-α), serum amyloid A (SAA) and Troponin T were assayed.

RESULTS

Total and cell specific AnV+MP expression were higher in the ACS group in both the CO and RA, with greater levels detected in the CO. Platelet activation showed positive correlation with Troponin-T and platelet MP in both CO and RA of the ACS group (r=0.4 for both; p=0.04 & p=0.03 respectively). Inflammatory markers levels did not differ between the ACS and SA patients.

CONCLUSIONS

Elevated coronary and systemic MP levels and positive correlation of platelet activation with Troponin-T and platelet MPs suggest a pathogenic role for MPs in ACS.