White R A, Fogarty T J, Kopchok G E, Wilson E, Ayres B, Zalewski M, Donayre C E
Division of Vascular Surgery, St. John's CV Research Center, Harbor-UCLA Medical Center, Torrance 90509, USA.
J Vasc Surg. 1996 Dec;24(6):1034-42. doi: 10.1016/s0741-5214(96)70050-2.
The study evaluated the deployment and healing of a novel self-expanding modular bifurcation endovascular prosthesis in a canine abdominal aortic aneurysm model. The endoluminal prosthesis consists of self-expanding nitinol stents lined by a synthetic prosthesis. One component of the device is a bifurcated body with a 12- to 14-mm diameter aortic segment and an integral 7- to 8-mm diameter iliac limb. The bifurcated body also has a stent-reinforced opening (pant-leg) for subsequent insertion of a contralateral 7- to 8-mm diameter iliac limb component.
Seventeen bifurcated prosthesis were placed; 7 were inserted through the left common carotid artery and 10 from the femoral arteries. With either route of access the 16F or 17F aortoiliac limb and the 13F iliac limb delivery catheters enabled easy passage and secure positioning of the bifurcated prostheses. Predeployment and postdeployment inspection of the dimensions and continuity of the aortoiliac prosthetic components were evaluated by cinefluoroscopy and intravascular ultrasonography (IVUS).
After deployment was done, interval patency was assessed with angiography, IVUS, and contrast-enhanced computed tomography with the prostheses removed for analysis at 1 week (n = 4), 1 month (n = 3), 3 months (n = 4), and 6 months (n = 6). Five of the first seven implanted prostheses had occlusion of segments of the device. In two dogs the bifurcated body and both legs were occluded. In the other three the nonoccluded leg and bifurcation body were fully patent. In the first seven animals IVUS at implantation showed compression of an iliac leg by the orifice of the contralateral iliac component. After concentric fixation of the flow divider was performed, only one additional iliac limb occlusion occurred in the next 10 animals. Cinefluoroscopy, computed tomography, IVUS imaging, and histologic analysis of retrieved specimens demonstrated healing of the aortoiliac prostheses without evidence of perigraft leaks.
This feasibility study demonstrates the ability to deploy and maintain acceptable patency of a self-expanding endoluminal, modular bifurcation prosthesis in a canine aortic model. Clinical evaluation of the device is planned for the near future.
本研究在犬腹主动脉瘤模型中评估了一种新型自膨式模块化分叉血管内假体的植入及愈合情况。腔内假体由内衬合成假体的自膨式镍钛合金支架组成。该装置的一个组件是一个分叉体，其主动脉段直径为12至14毫米，髂支直径为7至8毫米。分叉体还有一个带支架加强的开口（裤腿），用于随后插入对侧直径7至8毫米的髂支组件。
植入了17个分叉假体；7个通过左颈总动脉插入，10个通过股动脉插入。无论采用哪种入路，16F或17F的主髂支和13F的髂支输送导管都能使分叉假体轻松通过并安全定位。通过荧光透视和血管内超声（IVUS）评估主髂支假体组件在植入前和植入后的尺寸及连续性。
植入完成后，在1周（n = 4）、1个月（n = 3）、3个月（n = 4）和6个月（n = 6）时，通过血管造影、IVUS以及取出假体进行分析的对比增强计算机断层扫描评估间隔通畅情况。最初植入的7个假体中有5个出现了装置部分的闭塞。在2只犬中，分叉体和两条腿均闭塞。在另外3只犬中，未闭塞的腿和分叉体完全通畅。在前7只动物中，植入时的IVUS显示对侧髂支组件的开口压迫了一条髂腿。在对分流器进行同心固定后，在接下来的10只动物中仅又出现了1例髂支闭塞。荧光透视、计算机断层扫描、IVUS成像以及取出标本的组织学分析表明主髂支假体愈合良好，无移植物周围渗漏迹象。
这项可行性研究证明了在犬主动脉模型中植入并维持自膨式腔内模块化分叉假体可接受通畅性的能力。计划在不久的将来对该装置进行临床评估。
