The short and long-term efficiency of PCI is limited to in-stent restenosis (ISR) and stent thrombosis. Expansion of the stent in the target artery induces local injury of the vessel wall, primarily from the disruption of the endothelial lining. Following the injury, the reparatory mechanisms are activated leading to recovery of the endothelial coverage over the stent struts. Disruption of the endothelium causes the activation and adherence of platelets (minutes-hours) and recruitment of the monocytes and leukocytes (hours to days). The time that elapses between the endothelial disruption caused by the expanded stent and full coverage of the struts with new endothelial cells carries the highest risk of in-stent thrombosis.