Liu Wei, Li Qingqing, Song Ge, Lin Zhiqi, Gong Xiaofei, Feng Hanqing, Zhao Hugh Q, Zhou Yujie, Wang Yunbing, Fan Zhongyong, Liu Qing
Cardiovascular Department, Jishuitan Hospital, Beijing, 100035, P. R. China.
Beijing Advanced Medical Technologies, Ltd Inc, Beijing 102600, P. R. China.
Regen Biomater. 2025 Jul 9;12:rbaf073. doi: 10.1093/rb/rbaf073. eCollection 2025.
Bioresorbable stents (BRS) have emerged as a groundbreaking development in the field of percutaneous coronary intervention (PCI) as they address the long-standing concerns of metallic stents. Nevertheless, the observed higher thrombosis rates in the first generation BRS, i.e. ABSORB, might be attributed to their thicker struts, slower degradation rate and structural dismantling of partially endothelialized stents. In this study, measures have been taken to overcome these limitations include reducing strut thickness, modifying the structural design to maintain radial strength with thinner round cross section struts and using a new material poly(L-lactide-co-ɛ-caprolactone) (PLCL 95/5) that is tougher and degrade faster than poly(L-lactic acid) (PLLA).Given the excellent biocompatibility of PLCL materials, the US FDA has approved their use in clinical applications. PLCL stents can be used to treat diseases such as tracheal stenosis and tracheoesophageal fistula, and can also be applied in the construction of other tissue engineering stents, such as nerve conduitsand fat filling stents. The newly designed coronary stents were fabricated using a 3D printing technology with a rotating platform, coated with a paclitaxel coating and comprehensive in vitro research was conducted. It was the first to undergo tests in animals. Results showed the novel paclitaxel eluting PLCL stents had super-flexible structure, thinner round cross-sectional struts, a faster degradation profile and satisfactory hemocompatibility. With a paclitaxel dose of 0.57 μg/mm, the drug eluting stents showed very low degree of stenosis within 6 months of implantation in a porcine model. Overall, the results showed that the novel 3D printed PLCL drug eluting stent is a very promising candidate for next generation bioresorbable coronary stent.
生物可吸收支架(BRS)已成为经皮冠状动脉介入治疗(PCI)领域的一项突破性进展,因为它们解决了金属支架长期存在的问题。然而,第一代生物可吸收支架(即ABSORB)中观察到的较高血栓形成率,可能归因于其较厚的支架梁、较慢的降解速度以及部分内皮化支架的结构解体。在本研究中,已采取措施克服这些局限性,包括减小支架梁厚度、修改结构设计以使用更薄的圆形横截面支架梁维持径向强度,以及使用一种比聚(L-乳酸)(PLLA)更坚韧且降解更快的新型材料聚(L-丙交酯-共-ε-己内酯)(PLCL 95/5)。鉴于PLCL材料具有出色的生物相容性,美国食品药品监督管理局(US FDA)已批准其用于临床应用。PLCL支架可用于治疗气管狭窄和气管食管瘘等疾病,也可应用于其他组织工程支架的构建,如神经导管和脂肪填充支架。新设计的冠状动脉支架采用带旋转平台的3D打印技术制造,涂有紫杉醇涂层,并进行了全面的体外研究。它是首个在动物身上进行测试的。结果表明,新型紫杉醇洗脱PLCL支架具有超灵活的结构、更薄的圆形横截面支架梁、更快的降解特性以及令人满意的血液相容性。在猪模型中,紫杉醇剂量为0.57μg/mm时,药物洗脱支架在植入后6个月内显示出极低的狭窄程度。总体而言,结果表明新型3D打印PLCL药物洗脱支架是下一代生物可吸收冠状动脉支架非常有前景的候选产品。