Insertion of intracoronary shunts during off-pump coronary artery bypass surgery can induce a severe endothelial dysfunction. The purpose of this study was to propose a new intracoronary shunt design called Monoshunt, to avoid distal endothelial damage of the target artery in a porcine model. The use of the Monoshunt avoids distal endothelial denudation and allows distal coronary perfusion.