Abbott Vascular, 3200 Lakeside Drive, Santa Clara, CA 95054, USA.
EuroIntervention. 2009 Dec 15;5 Suppl F:F15-22. doi: 10.4244/EIJV5IFA3.
Bioresorbable polymeric vascular scaffolds may spawn a fourth revolution in percutaneous coronary intervention (PCI) and a novel treatment termed vascular restoration therapy. The principal design considerations for bioresorbable scaffolds are discussed in the context of physiological behaviour using the Bioabsorbable Vascular Solutions (BVS) ABSORB Cohort B scaffold (Abbott Vascular) as an example.
The lifecycle of a bioresorbable scaffold is divided into three phases: (1) revascularisation; (2) restoration; and (3) resorption. In the revascularisation phase spanning the first three months after intervention, the bioresorbable scaffold should perform comparably to metallic drug-eluting stents (DES) in terms of deliverability, radial strength, recoil, and neointimal thickening. The ensuing restoration phase is characterised by gradual erosion of radial strength and a loss of structural continuity, where the time scale at which each occurs is related to the hydrolytic degradation rate of the polymer. Natural vasomotion in response to external stimuli is theoretically possible at the end of this phase. Finally, in the resorption phase, the passive implant is systematically resorbed and processed by the body.
Limited clinical data speak to the potential of bioresorbable scaffolds as a new therapy, and future studies will prove critical to inspiring a fourth revolution in PCI.
生物可吸收聚合物血管支架可能引发经皮冠状动脉介入治疗（PCI）的第四次革命和一种名为血管修复治疗的新型治疗方法。以雅培血管的可吸收血管解决方案（BVS）ABSORB B 型支架为例，讨论了生物可吸收支架的主要设计考虑因素。
生物可吸收支架的生命周期分为三个阶段：（1）再血管化；（2）修复；（3）吸收。在介入后前三个月的再血管化阶段，生物可吸收支架在可输送性、径向强度、回缩和新生内膜增厚方面应与金属药物洗脱支架（DES）相当。随后的修复阶段的特点是径向强度逐渐侵蚀和结构连续性丧失，每个阶段发生的时间尺度与聚合物的水解降解率有关。在这个阶段结束时，理论上可以对外界刺激产生自然血管运动。最后，在吸收阶段，被动植入物被系统地吸收并被身体处理。
有限的临床数据表明生物可吸收支架作为一种新的治疗方法具有潜力，未来的研究对于激发 PCI 的第四次革命至关重要。
