International Circulation: What are the major characteristics of any future ideal stent platforms? Should we focus on the polymer， stent structure design， other factors such as antihyperplasia agents?
　　Prof. Windecker: In a session earlier this morning， I pointed out the major shortcomings of the technology that we have today. The first area that can be improved is efficacy because we have seen in trials comparing CABG versus percutaneous coronary intervention in patients with multivessel disease that PCI still remains inferior， indicating that efficacy remains an issue. There are also concerns that the earlier generation of DES may predispose to some type of late catch-up， which means that they are very efficacious up to one year but that advantage may be lost or diminished during longer term follow-up. Thirdly， is the area of patients with stent overlap where we clearly need improvement. These factors all relate to efficacy， but perhaps more importantly is the safety outcome. We have identified the problem of very late stent thrombosis with the early generation of DES， which is a multifactorial process， but probably related to some type of inflammatory reaction and pathologic vessel remodeling. Advances such as biodegradable polymers， polymer free drug release， or completely biodegradable stents are certainly advances that have the potential to improve long-term outcome.