Bioresorbable Vascular Scaffolds　― Are We Facing a Time of Crisis or One of Breakthrough? ―

摘要

Current 2nd-generation drug-eluting stents (DES) have dramatically improved clinical outcomes after percutaneous coronary intervention for coronary artery disease. However, DES implantation has major long-term limitations related to the permanent presence of foreign material in the coronary artery. Bioresorbable vascular scaffolds (BVS) were designed to overcome this limitation of permanent metal-based DES. However, because of immature manufacturing technology, BVS have several drawbacks, such as the thicker strut, poor deliverability, poor radio-opacity, poor radial strength, and cumbersome procedure to meet the principle of PSP (Preparation, Sizing, and Post-dilatation). Initial studies indicated that BVS outcomes were non-inferior to those of current DES and recent follow-up data of trials have revealed an additional critical drawback, higher rate of scaffold thrombosis, on the top of the existing limitations of BVS. Thus attention must be paid to the appropriate BVS-specific implantation protocols (i.e., PSP), as well as adequate intensity and duration of dual antiplatelet therapy. In any case, current BVS need further technical evolution to replace current metallic DES in routine clinical use.