Microparticles and sudden cardiac death due to coronary occlusion. The TIDE (Thrombus and Inflammation in sudden DEath) study

Abstract : Aims: The pattern of coronary occlusion might contribute to the onset of ventricular arrhythmia and sudden cardiac death (SCD). We hypothesized that the concentrations of microparticles might differ between SCD and ST-elevation myocardial infarction (STEMI) patients without rhythmic disturbances. Methods and results: The study sample includes consecutive patients hospitalized in two French tertiary centres between 2006 and 2011 for SCD with angiographically-proven acute coronary occlusion ( n=23), for STEMI ( n=61) and for a planned percutaneous coronary angioplasty (PCI) ( n=35, controls). During PCI blood was collected in the arch of aorta (systemic blood) before and after the procedure and in the culprit coronary lesion with an aspiration catheter. Microparticles were analysed by flow cytometry in a blinded manner to quantify endothelial (CD144+), platelet (CD41+), leucocyte (CD11a+) and erythrocyte (CD235a+) derived microparticles. After multivariate analysis, intracoronary concentrations of endothelial-derived microparticles were significantly higher in SCD than in STEMI patients (129 (74–185) vs. 50 (21–118) nb/µl; p < 0.01). Intracoronary and systemic blood concentrations of platelet-derived microparticles were not different between SCD and controls, suggesting limited impact of cardiac massage and electric defibrillation in microparticle concentrations. Conclusion: The higher concentrations of endothelial-derived microparticles in SCD due to acute coronary occlusion compared with STEMI without rhythmic disturbances suggests different patterns of acute coronary occlusion.