Erasmus University Medical Centre, Rotterdam, The Netherlands.
JACC Cardiovasc Interv. 2013 May;6(5):523-32. doi: 10.1016/j.jcin.2012.12.131.
This study sought to assess the vascular response of overlapping Absorb stents compared with overlapping newer-generation everolimus-eluting metallic platform stents (Xience V [XV]) in a porcine coronary artery model.
The everolimus-eluting bioresorbable vascular scaffold (Absorb) is a novel approach to treating coronary lesions. A persistent inflammatory response, fibrin deposition, and delayed endothelialization have been reported with overlapping first-generation drug-eluting stents.
Forty-one overlapping Absorb and overlapping Xience V (XV) devices (3.0 × 12 mm) were implanted in the main coronary arteries of 17 nonatherosclerotic pigs with 10% overstretch. Implanted coronary arteries were evaluated by optical coherence tomography (OCT) at 28 days (Absorb n = 11, XV n = 7) and 90 days (Absorb n = 11, XV n = 8), with immediate histological evaluation following euthanasia at the same time points. One animal from each time point was evaluated with scanning electron microscopy alone. A total of 1,407 cross sections were analyzed by OCT and 148 cross sections analyzed histologically.
At 28 days in the overlap, OCT analyses indicated 80.1% of Absorb struts and 99.4% of XV struts to be covered (p < 0.0001), corresponding to histological observations of struts with cellular coverage of 75.4% and 99.6%, respectively (p < 0.001). Uncovered struts were almost exclusively related to the presence of "stacked" Absorb struts, that is, with a direct overlay configuration. At 90 days, overlapping Absorb and overlapping XV struts demonstrated >99% strut coverage by OCT and histology, with no evidence of a significant inflammatory process, and comparable % volume obstructions.
In porcine coronary arteries implanted with overlapping Absorb or overlapping XV struts, strut coverage is delayed at 28 days in overlapping Absorb, dependent on the overlay configuration of the thicker Absorb struts. At 90 days, both overlapping Absorb and overlapping XV have comparable strut coverage. The implications of increased strut thickness may have important clinical and design considerations for bioresorbable platforms.
本研究旨在评估重叠 Absorb 支架与重叠新一代依维莫司洗脱金属平台支架（Xience V [XV]）在猪冠状动脉模型中的血管反应。
依维莫司洗脱生物可吸收血管支架（Absorb）是治疗冠状动脉病变的一种新方法。据报道，第一代药物洗脱支架重叠时会出现持续的炎症反应、纤维蛋白沉积和延迟内皮化。
将 41 个重叠的 Absorb 和重叠的 Xience V（XV）装置（3.0×12mm）植入 17 头非动脉粥样硬化猪的主冠状动脉内，扩张 10%。在 28 天（Absorb n=11，XV n=7）和 90 天（Absorb n=11，XV n=8）时，通过光学相干断层扫描（OCT）评估植入的冠状动脉，并在同一时间点安乐死后立即进行组织学评估。每个时间点的一只动物单独进行扫描电子显微镜检查。OCT 分析共分析了 1407 个横截面，组织学分析共分析了 148 个横截面。
在重叠的 28 天内，OCT 分析显示 80.1%的 Absorb 支架和 99.4%的 XV 支架被覆盖（p<0.0001），相应的组织学观察结果为 75.4%和 99.6%的支架具有细胞覆盖（p<0.001）。未覆盖的支架几乎完全与“堆叠”Absorb 支架有关，即具有直接覆盖的配置。90 天时，重叠的 Absorb 和重叠的 XV 支架在 OCT 和组织学上均显示>99%的支架覆盖，无明显炎症反应，且可比较的%体积阻塞。
在植入重叠 Absorb 或重叠 XV 支架的猪冠状动脉中，重叠 Absorb 支架的支架覆盖在 28 天延迟，这取决于较厚的 Absorb 支架的重叠配置。90 天时，重叠的 Absorb 和重叠的 XV 都有相似的支架覆盖。支架厚度的增加可能对生物可吸收平台具有重要的临床和设计意义。
