[Vascular stents: Approaches used to increase their clinical efficacy]

Using stents for endovascular restoration of blood flow made a revolution in vascular surgery, however, despite numerous variants of stents presented on the pharmacological market, there are no stents which would completely solve the problem of restenosis in the area of stent placement. In order to decrease growth of the neointima of the stented portions of vessels, stents coated with cytostatic and cytotoxic agents were worked out. To optimize the rate of drug release it was suggested to apply them in a mixture with biodegradable or biostable polymers. Placement of drug-eluting stents in a combination with dual antiplatelet therapy made it possible to decrease frequency of restenosis and reocclusion of the restored vascular lumen in patients, however it did not solve the problem of the development of thromboses and neointimal hyperplasia in the remote postoperative period. The article provides an overview of various modifications of vascular stents, clinical studies of stents of various manufacturers, as well as modern developments in manufacturing polymer/drug coatings and methods of applying them onto the stent. This is followed by analyzing the contribution of coatings to clinical efficacy of stents and prospects of increasing efficacy of vascular stents.