ABSTRACT
In-stent restenosis of about 25% after implantation of stainless steel stents is the major problem in PTCA procedures today. PTCA and the dilatation of the stent system means a severe trauma to the coronary artery wall. Wounds and fissures up to the media of the vessel wall are caused by high-pressure expansions of the balloon. The implantation of the foreign body (stent) and the vessel injury cause a complex immune reaction, with platelet and macrophage aggregation in the beginning and neointimal formation as the end result of the cascade.
