Everolimus-eluting bioresorbable vascular scaffolds: learning from the past to improve the future.

Bioresorbable vascular scaffolds (BVS) were developed to overcome the long-term limitations of metallic drug-eluting stents (DES). Shortcomings of DES include their permanent metallic cage which prevents normal coronary vasomotion, vascular remodeling, precludes future bypass grafting, and creates a nidus for very late stent thrombosis. With its transient scaffold which provides early mechanical support and subsequently resorbs thereby restoring physiologic properties and architecture of the vasculature, BVS offers a promising development within the field of interventional cardiology. Even though various BVS have been or are currently under development, the ABSORB BVS from Abbott Vascular was the first FDA approved device. In this review, we shed light on shortcomings of the current generation DES and theoretical advantages of BVS. In addition, we will discuss in detail clinical data from observational studies, meta-analyses, registries, and randomized controlled trials as it pertains to the efficacy and safety outcomes with everolimus-eluting BVS as compared to the current generation everolimus-eluting metallic stents (EES). We will summarize reasons behind the disappointing results from clinical trials and the failure of first generation BVS leading to its withdrawal from the market. Lastly, we will briefly review ongoing developments with the newer-generation BVS and future pre-clinical and clinical studies that are underway to evaluate the efficacy and safety of second-generation BVS.