Myocardial bridging is a potential risk factor of very late stent thrombosis of drug eluting stent

Drug eluting stents have been implanted worldwide and used in nearly 90% of percutaneous coronary interventions in China. Although many randomized trials have confirmed the efficacy and safety profile of drug eluting stents, they were not powered to detect or exclude the effect of drug eluting stents on rare events such as stent thrombosis. Several mechanisms of very late stent thrombosis have been postulated, but are not widely accepted. Virchow's triad describes the 3 main factors of thrombus formation - stasis of blood flow, endothelial injury and hypercoagulability. Myocardial bridging is a common congenital anomaly. Modern anatomy and angiography regard myocardial bridging as widespread, but its pathophysiological response is always ignored. According to Virchow's triad, myocardial bridging negatively affect endothelial function, and the turbulent shear stress and intimal trauma predispose the vessel toward thrombus formation. Therefore, we question whether a relationship between myocardial bridging and very late stent thrombosis of drug eluting stents exists. Also, we propose that myocardial bridging might be a potential risk factor of very late stent thrombosis of drug eluting stents; coronary artery bypass grafting might be a promising and novel choice in the treatment of myocardial bridging with severe stenosis in the coronary artery.