Objectives: To isolate aortic arch pathologies and keep the branches superior in arch patent, it always need physicians to do in-vivo fenestration or in-situ fenestration when performing the thoracic endovascular aortic repair (TEVAR). However, both of those fenestration techniques need structure modification of the stent-graft, which may affect their long-term stability. We designed an adjustable pre-fenestration aortic stent-graft to treat pathologies in this area and obtained a patent branch arteries. This study used this new designed stent-graft to perform fenestrated-TEVAR (f-TEVAR) in canine aorta. This study aims to identify its feasibility and safety through animal experiments, which might provide preliminary data for potential human implantation.
Methods: A total of 8 Labrador Retrievers were underwent f-TEVAR by using the new devices. Digital subtraction angiography was performed before and after f-TEVAR to evaluate the success of the procedures. All the canines were divided into a 4-week group (feeding for 4 weeks after operation) and a 12-week group (feeding for 12 weeks after operation). Computed tomography angiography (CTA) were performed before euthanasia.
Results: The success rate of operation was 100%. During the operation, there was no accident of major bleeding or failure to be released by fenestration. Adjustable fenestration worked well. No stent-graft migration was found in CTA at 4 weeks and 12 weeks after the operation. All branch arteries kept by the adjustable fenestration were patent.
Conclusions: The result of feasibility and safety of the new designed adjustable pre-fenestration aortic stent-graft in f-TEVAR of canine is acceptable. This study provides a reference for further optimization of this stent and human f-TEVAR implantation involving aortic arch lesions.
目的 : 为保留主动脉弓上分支动脉，对主动脉弓部病变进行开窗的胸主动脉腔内修复术(thoracic endovascular aortic repair，TEVAR)即开窗TEVAR(fenestrated-TEVAR，f-TEVAR)，其中最常用的是体外开窗和原位开窗技术。然而这两种技术均改变了支架的物理结构，可能影响支架的远期稳定性。笔者所在的团队设计了一款可调节预开窗主动脉覆膜支架并获得了专利。本研究旨在通过动物实验证明这款支架的可行性和安全性，为其临床应用提供前期数据。 方法 : 对8只健康的拉布拉多犬行可调节预开窗主动脉覆膜支架的腔内植入术和主动脉弓部的开窗操作，植入支架前后分别行数字减影血管造影，评价手术是否成功。术后将8只实验犬分为4周组(饲养4周组)和12周组(饲养12周组)。处死前1天行主动脉计算机体层摄影血管造影(computed tomography angiography，CTA)检查。 结果 : 手术成功率为100%。术中无大出血发生，无开窗无法释放事件发生。开窗位置移动平滑，支架退出均顺利。4周和12周的主动脉CTA复查结果提示支架无移位。所有弓上动脉均保持通畅。 结论 : 使用可调节预开窗主动脉覆膜支架在犬类主动脉植入模型中具有良好的可行性和安全性。本研究为该款支架的进一步优化和涉及主动脉弓部病变的人类f-TEVAR植入提供了参考。.
Keywords: adjustable pre-fenestration aortic stent-graft; aortic arch; canine; fenestrated-thoracic endovascular aortic repair.