Plaque Erosion Prospective Study ii

Plaque erosion is associated with myocardial infarction (MI) in about 30% of cases and may require a different management approach to plaque rupture. The investigators hypothesise that plaque erosion leads to higher levels of apoptotic circulating endothelial cells (CECs) compared to plaque rupture. Aims: To compare associations between plaque erosion and plaque rupture with numbers and types of apoptotic CECs in patients with non-ST elevation MI (NSTEMI) and stable coronary artery disease controls (CAD). Additional aims are to explore signals of cellular stress (mitochondrial dsDNA), sub-populations of activated neutrophils, circulating endothelial progenitor cells and erosion-specific plasma biomarkers. Methods: Prospective observational study of 80 patients with NSTEMI and 40 patients with stable CAD. Plaque erosion or rupture will be identified by intracoronary Optical Coherence Tomography (OCT). CECs and neutrophils will be quantified and characterised using flow cytometry looking at markers of cell death and neutrophil activation. Plasma will be analysed by proteomic methods (Olink) and for mitochondrial dsDNA. Potential importance of findings: This study will provide evidence for the hypothesised mechanism of plaque erosion and clarify if biomarker analysis in NSTEMI patients provides a basis for non-invasive diagnosis of plaque erosion versus rupture.