The endothelium is a regulator of vascular homeostasis, vascular tone and structure and exerts anticoagulant, antiplatelet and fibrinolytic properties. Endothelial dysfunction is characterized by a decreased vascular bioavailability of nitric oxide probably due to an increased degradation of nitric oxide via its interaction with locally produced reactive oxygen species. No clinical studies have investigated whether peri- and postoperative endothelial dysfunction is associated with an increased risk of perioperative myocardial injury. Endothelial dysfunction may be a key element in the development of perioperative myocardial injury.