Influence of endoleak positions on the pressure shielding ability of stent-graft after endovascular aneurysm repair (EVAR) of abdominal aortic aneurysm (AAA).
BACKGROUND
Abdominal aortic aneurysm (AAA) is a kind of dangerous aortic vascular disease, which is characterized by abdominal aorta partial enlargement. At present, endovascular aneurysm repair (EVAR) is one of the main treatments of abdominal aortic aneurysm. However for some patients after EVAR the aneurysm re-expanded and even ruptured, leading to poor postoperative effect. The stent-graft endoleak after EVAR was realized to influence the AAA in-sac pressure and contribute to the aneurysm re-enlargement.


METHODS
In order to analyze the influence of endoleaks positions on the pressure shielding ability of stent-graft after EVAR, type I and type III endoleak models were reconstructed based on computed tomography (CT) scan images, and the hemodynamic environment in AAA was numerically simulated.


RESULTS
When the endoleak was at the proximal position the pressure shielding ability will be obviously weakened. While, the pressure shielding ability was higher in the systole phase than that in diastole phase when the endoleak located at the middle or distal positions. Unfortunately, when the endoleak located at the proximal position, the pressure shielding ability would be relatively weak in the whole cardiac cycle.


CONCLUSIONS
The results revealed that the influence of endoleaks on pressure shielding ability of stent-graft was both location and time specific.
Key Laboratory for Biomechanics and Mechanobiology of Ministry of Education, School of Biological Science and Medical Engineering, Beihang University, Beijing, China.
Jie
J
Li
Key Laboratory for Biomechanics and Mechanobiology of Ministry of Education, School of Biological Science and Medical Engineering, Beihang University, Beijing, China.
Xiaopeng
X
Tian
National Research Center for Rehabilitation Technical Aids, Beijing, China.
Zhenze
Z
Wang
Department of Vascular and Endovascular Surgery, The Chinese PLA General Hospital, Beijing, China.
Jiang
J
Xiong
Key Laboratory for Biomechanics and Mechanobiology of Ministry of Education, School of Biological Science and Medical Engineering, Beihang University, Beijing, China.|National Research Center for Rehabilitation Technical Aids, Beijing, China.
Yubo
Y
Fan
Key Laboratory for Biomechanics and Mechanobiology of Ministry of Education, School of Biological Science and Medical Engineering, Beihang University, Beijing, China.
Xiaoyan
X
Deng
Key Laboratory for Biomechanics and Mechanobiology of Ministry of Education, School of Biological Science and Medical Engineering, Beihang University, Beijing, China. saq@buaa.edu.cn.
Anqiang
A
Sun
Key Laboratory for Biomechanics and Mechanobiology of Ministry of Education, School of Biological Science and Medical Engineering, Beihang University, Beijing, China. liuxiao@buaa.edu.cn.
Xiao
X
Liu
D017544:Aortic Aneurysm, Abdominal / Q000000981:diagnostic imaging / Q000503:physiopathology* / Q000601:surgery*; D001027:Aortography; D003198:Computer Simulation; D057867:Endoleak; D057510:Endovascular Procedures / Q000379:methods*; D006439:Hemodynamics; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008955:Models, Cardiovascular; D011312:Pressure; D015607:Stents; D014057:Tomography, X-Ray Computed
Abdominal aortic aneurysm; Endoleak; Pressure shielding ability