Tissue localization of MPO has been described in a variety of inflammatory conditions,[19] MPO was found to be increased in human atheromas more than a decade ago.[21] More recently, studies have focused on the presence of MPO not only in early lesions, but also in acute complications of atherosclerosis and plaque vulnerability.[9] The link between MPO levels and CAD is strongly supported by epidemiological studies. This evidence concerns the gene MPO and coronary artery disorder.