The following are characteristics of a vulnerable plaque except:a. High concentration of macrophages
High concentration of collagen. It is in fact the low concentration of collagen (due to low levels of smooth muscle cells) that results in the collagen-poor thin cap of vulnerable plaques. These plaques display high concentrations of macrophages (foam cells) and T-lymphocytes (producing interferon-γ), as well as significant neovascularization and a large necrotic core that is vulnerable to rupture and propagate thrombosis. In fact, saphenous vein graft (SVG) lesions tend to have a larger necrotic core than native coronary lesions, which is one factor that contributes to greater plaque friability and worse outcomes with SVG stenting.