Stent restenosis and thrombosis: etiology, treatment, and outcomes.
The implementation of bare metal stents and later drug eluting stents (DES) proved to be an important step forward in reducing rates of restenosis after percutaneous coronary intervention. Despite all the benefits of DES, concerns have been raised over their long term safety as especially stent thrombosis sets patients at risk. In view of the overall low frequency of stent thrombosis, large sample sizes are needed to evaluate accurately treatment differences between stents. However, a consistent finding from randomized, controlled trials of DES versus bare metal stents is the significantly reduced reintervention rate associated with DES use. The clinical presentation of restenosis is recurrent angina or acute coronary syndrome. Optimal implantation of the stent in the vessel and adequate antiplatelet therapy are of utmost significance to provide best results. Intravascular imaging often helps to provide optimal delivery of the stent. Newer stents have now been developed. Especially DES with biogradable polymers, novel coatings of the stent, and polymer free DES have to be mentioned and early results seem to be promising. The perspective of bioresorbable DES platforms includes the additional benefits of improved recovery in vessel function and the potential for reducing the requirement for prolonged dual antiplatelet therapy. This article reviews the etiology, treatment options and outcome of in stent restenosis and gives an overview about the new developments in the field of stent technology.