Jayet Jérémie, Canonge Jennifer, Heim Frédéric, Coggia Marc, Chakfé Nabil, Coscas Raphaël
Department of Vascular Surgery, Ambroise Paré University Hospital, Assistance Publique-Hôpitaux de Paris (AP-HP), 92100 Boulogne-Billancourt, France.
Groupe Européen de Recherche sur les Prothèses Appliquées à la Chirurgie Vasculaire (GEPROVAS), 67085 Strasbourg, France.
J Clin Med. 2023 Jul 26;12(15):4911. doi: 10.3390/jcm12154911.
A fenestrated endograft (FE) is the first-line endovascular option for juxta and pararenal abdominal aortic aneurysms. A physician-modified stent-graft (PMSG) and laser in situ fenestration (LISF) have emerged to circumvent manufacturing delays, anatomic standards, and the procedure's cost raised by FE. The objective was to compare different fenestrations from a mechanical point of view.
In total, five Zenith Cook fenestrations (Cook Medical, Bloomington, IN, USA) and five Anaconda fenestrations (Terumo Company, Inchinnan, Scotland, UK) were included in this study. Laser ISF and PMSG were created on a Cook TX2 polyethylene terephthalate (PET) cover material (Cook Medical, Bloomington, IN, USA). In total, five LISFs and fifty-five PMSG were created. All fenestrations included reached an 8 mm diameter. Radial extension tests were then performed to identify differences in the mechanical behavior between the fenestration designs. The branch pull-out force was measured to test the stability of assembling with a calibrated 8 mm branch. Fatigue tests were performed on the devices to assess the long-term outcomes of the endograft with an oversized 9 mm branch.
The results revealed that at over 2 mm of oversizing, the highest average radial strength was 33.4 ± 6.9 N for the Zenith Cook fenestration. The radial strength was higher with the custom-made fenestrations, including both Zenith Cook and Anaconda fenestrations (9.5 ± 4.7 N and 4.49 ± 0.28 N). The comparison between LISF and double loop PMSG highlighted a higher strength value compared with LISF (3.96 N ± 1.86 vs. 2.7 N ± 0.82; = 0.018). The diameter of the fenestrations varied between 8 and 9 mm. As the pin caliber inserted in the fenestration was 9 mm, one could consider that all fenestrations underwent an "elastic recoil" after cycling. The largest elastic recoil was observed in the non-reinforced/OC fenestrations (40%). A 10% elastic recoil was observed with LISF.
In terms of mechanical behavior, the custom-made fenestration produced the highest results in terms of radial and branch pull-out strength. Both PMSG and LISF could be improved with the standardization of the fenestration creation protocol.
开窗型腔内移植物（FE）是近肾腹主动脉瘤和肾旁腹主动脉瘤血管腔内治疗的一线选择。为规避FE带来的制造延迟、解剖学标准及手术成本问题，出现了医生改良型支架移植物（PMSG）和激光原位开窗（LISF）技术。本研究旨在从力学角度比较不同的开窗技术。
本研究共纳入5个Cook Zenith开窗型移植物（美国印第安纳州布卢明顿市Cook Medical公司）和5个Anaconda开窗型移植物（英国苏格兰因钦南市泰尔茂公司）。在Cook TX2聚对苯二甲酸乙二酯（PET）覆盖材料（美国印第安纳州布卢明顿市Cook Medical公司）上制作激光原位开窗和医生改良型支架移植物。共制作了5个激光原位开窗和55个医生改良型支架移植物。所有开窗均达到8毫米直径。然后进行径向延伸测试，以确定开窗设计在力学行为上的差异。测量分支拔出力，以测试与校准后的8毫米分支组装的稳定性。对这些装置进行疲劳测试，以评估使用超大9毫米分支的腔内移植物的长期效果。
结果显示，在超径超过2毫米时，Cook Zenith开窗型移植物的平均径向强度最高，为33.4±6.9牛。定制开窗型移植物（包括Cook Zenith开窗型移植物和Anaconda开窗型移植物）的径向强度更高（分别为9.5±4.7牛和4.49±0.28牛）。激光原位开窗与双环医生改良型支架移植物的比较突出显示，医生改良型支架移植物的强度值更高（3.96牛±1.86对2.7牛±0.82；P=0.018）。开窗直径在8至9毫米之间变化。由于插入开窗的销钉口径为9毫米，可以认为所有开窗在循环后都经历了“弹性回缩”。在非强化/OC开窗中观察到最大的弹性回缩（40%）。激光原位开窗的弹性回缩为10%。
在力学行为方面，定制开窗在径向和分支拔出强度方面取得了最高结果。医生改良型支架移植物和激光原位开窗均可通过开窗制作方案的标准化加以改进。
