Bioresorbable Vascular Scaffolds for Coronary Revascularization

Contemporary metallic drug-eluting stents are associated with very good 1-year outcomes but an ongoing risk of stent-related adverse events (thrombosis, myocardial infarction, restenosis) after 1 year. The pathogenesis of these very late events is likely related to the permanent presence of the metal stent frame or polymer. Bioresorbable scaffolds have been developed to provide drug delivery and mechanical support functions similar to metallic drug-eluting stents, followed by complete resorption with recovery of more normal vascular structure and function, potentially improving very late clinical outcomes. A first-generation bioresorbable scaffold has been demonstrated to be noninferior to a contemporary metallic drug-eluting stents for overall 1-year patient-oriented and device-oriented outcomes. Increased rates of scaffold thrombosis and target vessel-related myocardial infarction were noted that may be mitigated by improved patient and lesion selection, procedural technique, and device iteration. Large-scale, randomized, clinical trials are ongoing to determine the long-term relative efficacy and safety of bioresorbable scaffolds compared with current metallic drug-eluting stents.