Taher Fadi, Falkensammer Juergen, McCarte Jamie, Strassegger Johann, Uhlmann Miriam, Schuch Philipp, Assadian Afshin
Department of Vascular and Endovascular Surgery, Wilhelminenspital, Vienna, Austria.
Department of Vascular and Endovascular Surgery, Wilhelminenspital, Vienna, Austria; Sigmund Freud University, Vienna, Austria.
J Vasc Surg. 2017 Jun;65(6):1591-1597. doi: 10.1016/j.jvs.2016.10.108. Epub 2017 Feb 16.
The fenestrated Anaconda endograft (Vascutek/Terumo, Inchinnan, UK) is intended for the treatment of abdominal aortic aneurysms with an insufficient infrarenal landing zone. The endografts are custom-made with use of high-resolution, 1-mm-slice computed tomography angiography images. For every case, a nonsterile prototype and a three-dimensional (3D) model of the patient's aorta are constructed to allow the engineers as well as the physician to test-implant the device and to review the fit of the graft. The aim of this investigation was to assess the impact of 3D model construction and prototype testing on the design of the final sterile endograft.
A prospectively held database on fenestrated endovascular aortic repair patients treated at a single institution was completed with data from the Vascutek engineers' prototype test results as well as the product request forms. Changes to endograft design based on prototype testing were assessed and are reported for all procedures.
Between April 1, 2013, and August 18, 2015, 60 fenestrated Anaconda devices were implanted. Through prototype testing, engineers were able to identify and report potential risks to technical success related to use of the custom device for the respective patient. Theoretical concerns about endograft fit in the rigid model were expressed in 51 cases (85.0%), and the engineers suggested potential changes to the design of 21 grafts (35.0%). Thirteen cases (21.7%) were eventually modified after the surgeon's testing of the prototype. A second prototype was ordered in three cases (5.0%) because of extensive changes to endograft design, such as inclusion of an additional fenestration. Technical success rates were comparable for grafts that showed a perfect fit from the beginning and cases in which prototype testing resulted in a modification of graft design.
Planning and construction of fenestrated endografts for complex aortic anatomies where exact fit and positioning of the graft are paramount to allow cannulation of the aortic branches are challenging. In the current series, approximately one in five endografts was modified after prototype testing in an aortic model. Eventually, success rates were comparable between the groups of patients with a good primary prototype fit and those in which the endograft design was altered. Prototype testing in 3D aortic models is a valuable tool to test the fit of a custom-made endograft before implantation. This may help avoid potentially debilitating adverse events associated with misaligned fenestrations and unconnected aortic branches.
带开窗的Anaconda血管内移植物（Vascutek/Terumo公司，英国因钦南）旨在治疗肾下着陆区不足的腹主动脉瘤。这些血管内移植物是利用高分辨率、1毫米层厚的计算机断层扫描血管造影图像定制的。对于每一个病例，都会构建一个非无菌原型以及患者主动脉的三维（3D）模型，以便工程师和医生对该装置进行测试植入，并检查移植物的贴合情况。本研究的目的是评估3D模型构建和原型测试对最终无菌血管内移植物设计的影响。
一个前瞻性保存的关于在单一机构接受带开窗血管内主动脉修复术患者的数据库，补充了来自Vascutek工程师的原型测试结果以及产品申请表中的数据。评估了基于原型测试对血管内移植物设计的更改，并报告了所有手术的情况。
在2013年4月1日至2015年8月18日期间，植入了60个带开窗的Anaconda装置。通过原型测试，工程师能够识别并报告与为相应患者使用定制装置相关的技术成功的潜在风险。在51例（85.0%）病例中表达了对刚性模型中血管内移植物贴合情况的理论担忧，工程师建议对21个移植物（35.0%）的设计进行潜在更改。在外科医生对原型进行测试后，最终有13例（21.7%）进行了修改。由于血管内移植物设计发生广泛变化，如增加一个开窗，3例（5.0%）订购了第二个原型。对于一开始就显示完美贴合的移植物和原型测试导致移植物设计修改的病例，技术成功率相当。
对于复杂的主动脉解剖结构，规划和构建带开窗的血管内移植物具有挑战性，在这种情况下，移植物的精确贴合和定位对于主动脉分支的插管至关重要。在本系列研究中，大约五分之一的血管内移植物在主动脉模型的原型测试后进行了修改。最终，初次原型贴合良好的患者组与血管内移植物设计发生改变的患者组之间的成功率相当。在3D主动脉模型中进行原型测试是一种在植入前测试定制血管内移植物贴合情况的有价值工具。这可能有助于避免与开窗未对齐和主动脉分支未连接相关的潜在致残性不良事件。
