Bioresorbable Scaffolds: Contemporary Status and Future Directions

Abstract

Percutaneous coronary intervention, which is safe, effective, and timely, has become an important treatment for coronary artery diseases and has been widely used in clinical practice. However, there are still some problems that urgently need to be solved. Permanent vessel caging through metallic implants not only prevents the process of positive vessel remodeling and the restoration of vascular physiology but also makes the future revascularization of target vessels more difficult. Bioresorbable scaffolds (BRSs) have been developed as a potential solution to avoid the above adverse reactions caused by permanent metallic devices. BRSs provide temporary support to the vessel wall in the short term and then gradually degrade over time to restore the natural state of coronary arteries. Nonetheless, long-term follow-up of large-scale trials has drawn considerable attention to the safety of BRSs, and the significantly increased risk of late scaffold thrombosis (ScT) limits its clinical application. In this review, we summarize the current status and clinical experiences of BRSs to understand the application prospects and limitations of these devices. In addition, we focus on ScT after implantation, as it is currently the primary drawback of BRS. We also analyze the causes of ScT and discuss improvements required to overcome this serious drawback and to move the field forward.

Iron corroded granules inhibiting vascular smooth muscle cell proliferation

“…Thus, stents that specifically target VSMCs but not the endothelium constitute the next revolution in interventional technology. Bioresorbable stents were heralded as the fourth revolution in stents and were designed to avoid the shortcomings posed by DES [ [29] , [30] ]. Iron and iron alloys are candidate materials for bioresorbable stents because of their excellent mechanical performance and biocompatibility [ 12 , 13 , 24 ].…”

Crosstalk between arterial components and bioresorbable, 3-D printed poly-l-lactic acid scaffolds

“…Degradation was more severe in the rat abdominal aorta than in the rabbit carotid artery after PLS implantation Degradation is the most important characteristic of a bioresorbable endovascular scaffold. 9,10,12 Hence, we applied SEM to show the extent of degradation on the surface of a 3Dprinted scaffold, in combination with Alcian blue staining. For the staining, blue color indicated a positive result.…”

“…9 The corrosion of metallic material-based BRSs often occurs via complex mechanisms that produce a wide range of products; the degradation time, rates, and products of corrosion can differ fundamentally in vitro and in vivo. [10][11][12] For example, the first Mg-based stent, which was designed by Biotronik (AMS-1), was degraded in electrolyte solutions in about 2 months in vitro, 11 while clinical trials performed to assess feasibility showed that AMS-1 was completely degraded at 3 months. 12 Elastic and muscular arteries, such as the abdominal aorta and carotid artery, respectively, are composed of different histological structures in the cardiovascular system.…”

Drug-Eluting, Bioresorbable Cardiovascular Stents─Challenges and Perspectives

“…The theoretical advantages of these designs promised flexion in the blood vessel, less cyclical wear on the arterial walls, and an adaptive vascular response . The use of drug-eluting, bioresorbable polymeric stents (BRSs) promised to support the vessels by maintaining their physiological functions and reducing the risk of postimplantation adverse effects . One example is the Abbott Vascular Absorb everolimus-eluting bioresorbable stent (Figure ).…”