用于血管内腹主动脉瘤修复的标准型和开窗型覆膜支架固定强度的比较。

Comparison of the fixation strength of standard and fenestrated stent-grafts for endovascular abdominal aortic aneurysm repair.

作者信息

Zhou Samuel S N, How Thien V, Rao Vallabhaneni S, Gilling-Smith Geoffrey L, Brennan John A, Harris Peter L, McWilliams Richard

机构信息

Department of Clinical Engineering, University of Liverpool, England, UK.

出版信息

J Endovasc Ther. 2007 Apr;14(2):168-75. doi: 10.1177/152660280701400208.

DOI:10.1177/152660280701400208

PMID:17484532

Abstract

PURPOSE

To determine whether fenestrated stent-grafts provide better stability to resist migration than standard non-fenestrated stent-grafts.

METHODS

Truncated fenestrated stent-grafts with a single fenestration were deployed in bovine aortic segments with a side branch. Balloon-expandable stents were then delivered into the branches. Similarly, standard stent-grafts of the same dimensions were deployed for comparison. The aorta was pressurized to achieve stent-graft oversizing of 5%, 10%, or 20%. The force required to cause distal migration was recorded by a digital force gauge attached to the stent-graft.

RESULTS

Displacement of the stent-grafts occurred in 2 distinct phases: an initial yield during which the barbs embedded in the aortic wall and a final displacement leading to significant migration and dislodgement of the device. The displacement force that initiated each phase was dependent upon the degree of oversizing of the stent-graft relative to the aortic diameter. For 5%, 10%, and 20% oversizing, the mean displacement forces in the initial displacement phase were 3.39+/-0.37, 4.32+/-0.63, and 7.69+/-1.18 N, respectively, in non-fenestrated grafts and 10.48+/-1.23, 11.45+/-1.48, 12.12+/-1.42 N in fenestrated grafts. The displacement forces in the final displacement phase were 8.10+/-0.92, 10.76+/-1.74, and 16.82+/-0.92 N for non-fenestrated and 22.56+/-1.60, 28.24+/-1.56, and 33.01+/-1.75 N for fenestrated stent-grafts. The differences in displacement forces between standard and fenestrated stent-grafts were significant for both phases (p<0.001) at all oversizing levels.

CONCLUSION

Improvement in fixation strength was noted with increasing stent-graft oversizing of up to 20%. Fenestrated stent-grafts offer higher ultimate fixation compared to standard devices. However, the ultimate fixation strength was not recruited until an initial phase of short migration occurred as the barbs engaged. While this movement is inconsequential with standard stent-grafts, it has the potential to crush the stents placed into aortic side branches with fenestrated endografts.

摘要

目的

确定开窗支架型人工血管是否比标准非开窗支架型人工血管具有更好的抗移位稳定性。

方法

将带有单个开窗的截断式开窗支架型人工血管植入带有侧支的牛主动脉段。然后将球囊可扩张支架输送至分支内。同样，植入相同尺寸的标准支架型人工血管用于比较。对主动脉进行加压，使支架型人工血管的尺寸过大5%、10%或20%。通过连接到支架型人工血管的数字测力计记录引起远端移位所需的力。

结果

支架型人工血管的移位发生在2个不同阶段：初始屈服阶段，在此期间倒刺嵌入主动脉壁；最终移位阶段，导致装置显著移位和脱落。启动每个阶段的移位力取决于支架型人工血管相对于主动脉直径的尺寸过大程度。对于尺寸过大5%、10%和20%的情况，在非开窗移植物中，初始移位阶段的平均移位力分别为3.39±0.37、4.32±0.63和7.69±1.18 N，在开窗移植物中分别为10.48±1.23、11.45±1.48和12.12±1.42 N。非开窗支架型人工血管在最终移位阶段的移位力为8.10±0.92、10.76±1.74和16.82±0.92 N，开窗支架型人工血管为22.56±1.60、28.24±1.56和33.01±1.75 N。在所有尺寸过大水平下，标准和开窗支架型人工血管之间的移位力差异在两个阶段均具有显著性（p<0.001）。

结论

随着支架型人工血管尺寸过大增加至20%，固定强度有所改善。与标准装置相比，开窗支架型人工血管具有更高的最终固定效果。然而，在倒刺嵌入时发生的短距离移位的初始阶段之后，最终固定强度才得以发挥。虽然这种移动对于标准支架型人工血管来说无关紧要，但对于带有开窗内支架的主动脉侧支内放置的支架，它有可能将其压碎。