 For the majority of Coronary Artery Disease CAD, treatment with Percutaneous Transluminal Coronary Angioplasty PTCA provides high initial procedural success. However, the medium to long-term complications range from rather immediate elastic recoil or vessel contraction to longer processes like smooth muscle cell proliferation and excessive production of extra cellular matrix, thrombus formation and atherosclerotic changes like restenosis or angiographic re-narrowing. The reported incidence of restenosis after PTCA ranges from 30-50. Such rates of recurrence have serious economic consequences. Bare Metal Stents BMS, designed to address the limitations of PTCA, reduced the angiographic and clinical restenosis rates in de novo lesions compared to PTCA alone and decreased the need for CABG. BMS substantially reduced the incidence of abrupt artery closure, but restenosis still occurred in about 20-40 of cases, necessitating repeat procedures. The invention of Drug Eluting Stents DES significantly improved on the principle of BMS by adding an antiproliferative drug directly immobilized on the stent surface or released from a polymer matrix, which inhibits neointimal hyperplasia. The introduction of DES greatly reduced the incidence of restenosis and resulted in a better safety profile as compared to BMS with systemic drug administration. These advantages and a lower cost compared to surgical interventions has made DES an attractive option to treat coronary artery disease. 