Recent insights from scanning electron microscopic assessment of durable polymer-coated drug-eluting stents

Research on drug-eluting stents (DES) has had to be highly dynamic because of the rapid modification of stent platforms and coatings, and even the development of completely new stent designs and concepts. Through various mechanisms, coating irregularities of DES might contribute to some of the remaining problems of DES, such as (late) stent thrombosis and (side-branch) restenosis. This article sheds light on recent bench-top testing of DES coatings, providing an update on the latest examinations of DES coating morphology with scanning electron microscopy. It also reviews the different methods used to quantify DES coating irregularities, and proposes stepwise examination of coatings of both customary and novel DES. There is still a need to carefully assess novel DES with scanning electron microscopy in order to obtain data that may complement preclinical and clinical studies. Stent manufacturers have a responsibility to continuously monitor the quality of their products and generally strive to perfect their devices. In addition, independent, external assessment of DES coatings was shown to provide valuable data that permit meaningful comparisons of different DES types. Likewise, interventional cardiologists may use such complementary information from bench-side research as one of the pieces of evidence available to tailor therapy in clinical practice