Effects on Aortoiliac Fluid Dynamics After Endovascular Sealing of Abdominal Aneurysms

Abstract

Objectives:

To evaluate the effects on aortoiliac fluid dynamics after the implantation of an endograft based on endovascular aneurysm sealing (EVAS) versus endovascular aneurysm repair (EVAR) strategy.

Methods:

An adaptive geometrical deformable model was used for aortic lumen segmentation in 8 patients before and after the surgery. Abdominal aneurysms were treated with an endograft based on the EVAS system (Nellix, n = 4) and with a device based on an anatomical fixation technology (n = 4). Pressure, blood velocity, and wall shear stress (WSS) were estimated at different aortic regions using computational fluid dynamics methods. Physiologic inlet/outlet flow values at the abdominal aorta, the celiac trunk, and the mesenteric and the renal arteries were set. Pressure references were set at iliac arteries outlet.

Results:

Maximum aneurysm sizes were similar for both groups in the preoperative scans. The lumen area was lower after EVAR (P < .05) and EVAS (P < .01) compared to preoperative aortic lumen sizes. Pressure increase was higher in the proximal abdominal aorta after EVAS compared to EVAR (2.3 ± 0.3 mm Hg vs 0.9 ± 0.3 mm Hg, P < .001). Peak blood velocities inside the endografts were 3-fold higher for EVAS compared to EVAR (54 ± 5 cm/s vs 17 ± 4 cm/s, P < .01). Velocities at the iliac arteries also remained higher for EVAS (38 ± 4 cm/s vs 24 ± 4 cm/s, P < .05). Peak WSS at the iliac arteries remained higher for EVAS compared to EVAR group (P < .05).

Conclusion:

The significant modification of the aortic bifurcation anatomy after EVAS alters aortoiliac fluid dynamics, showing a pressure impact at the renal arteries level and an acceleration of the blood velocity at the iliac region with a concomitant increase in peak WSS.

Keywords

abdominal aortic aneurysm Nellix endograft computational fluid dynamics geometric deformable models sac anchoring prosthesis endovascular repair

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References

Bockler

Holden

Thompson

. Multicenter nellix endovascular aneurysm sealing system experience in aneurysm sac sealing. J Vasc Surg. 2015;62(2):290–298.

Krievins

Holden

Savlovskis

. Evar using the nellix sac-anchoring endoprosthesis: treatment of favourable and adverse anatomy. Eur J Vasc Endovasc Surg. 2011;42(1):38–46.

Shaikh

Chan

Oshin

. Changes in aortic volumes following endovascular sealing of abdominal aortic aneurysms with the nellix endoprosthesis. J Endovasc Ther. 2015;22(6):881–885.

Casciaro

El-Batti

Chironi

. Deformable surface model for the evaluation of abdominal aortic aneurysms treated with an endovascular sealing system. Ann Biomed Eng. 2016;44(5):1381–1391.

Boersen

Schuurmann

Slump

. Changes in aortoiliac anatomy after elective treatment of infrarenal abdominal aortic aneurysms with a sac anchoring endoprosthesis. Eur J Vasc Endovasc Surg. 2016;51(1):56–62.

Boersen

Groot Jebbink

Versluis

. Flow and wall shear stress characterization after endovascular aneurysm repair and endovascular aneurysm sealing in an infrarenal aneurysm model. J Vasc Surg. 2017;66(6):1844–1853.

Larrabide

Geers

Morales

Aguilar

Rufenacht

. Effect of aneurysm and ICA morphology on hemodynamics before and after flow diverter treatment. J Neurointerv Surg. 2015;7(4):272–280.

Larrabide

Villa-Uriol

Cardenes

. Angiolab—a software tool for morphological analysis and endovascular treatment planning of intracranial aneurysms. Comput Methods Programs Biomed. 2012;108(2):806–819.

Diethrich

. Novel sealing concept in the endologix afx unibody stent-graft. J Cardiovasc Surg (Torino). 2014;55(1):93–102.

10.

Weller

Tabor

Jasak

Fureby

. A tensorial approach to computational continuum mechanics using object-oriented techniques. Comput Phys. 1998;12:620–631.

11.

Geers

Larrabide

Morales

Frangi

. Approximating hemodynamics of cerebral aneurysms with steady flow simulations. J Biomech. 2014;47(1):178–185.

12.

Morales

Larrabide

Geers

Aguilar

Frangi

. Newtonian and non-newtonian blood flow in coiled cerebral aneurysms. J Biomech. 2013;46(13):2158–2164.

13.

Bernardini

Larrabide

Morales

. Influence of different computational approaches for stent deployment on cerebral aneurysm haemodynamics. Interface focus. 2011;1(3):338–348.

14.

Osada

. Physiological aspects of the determination of comprehensive arterial inflows in the lower abdomen assessed by doppler ultrasound. Cardiovasc Ultrasound. 2012;10:13.

15.

Osada

Katsumura

Hamaoka

. Reduced blood flow in abdominal viscera measured by doppler ultrasound during one-legged knee extension. J Appl Physiol (1985). 1999;86(2):709–719.

16.

Osada

Murase

Kime

. Arterial blood flow of all abdominal-pelvic organs using doppler ultrasound: range, variability and physiological impact. Physiol Meas. 2007;28(10):1303–1316.

17.

Psacharopulo

Ferri

Ferrero

. Comparison of outcomes for short-neck and juxtarenal aortic aneurysms treated with the nellix endograft versus conventional endovascular aneurysm sealing. J Vasc Surg. 2017;66(5):1371–1378.

18.

Coulston

Baigent

Selvachandran

Jones

Torella

Fisher

. The impact of endovascular aneurysm repair on aortoiliac tortuosity and its use as a predictor of iliac limb complications. J Vasc Surg. 2014;60(3):585–589.

19.

Groot Jebbink

Mathai

Boersen

. Hemodynamic comparison of stent configurations used for aortoiliac occlusive disease. J Vasc Surg. 2017;66(1):251–260 e251.

20.

Back

Gasser

Michel

Caligiuri

. Biomechanical factors in the biology of aortic wall and aortic valve diseases. Cardiovasc Res. 2013;99(2):232–241.

21.

England

Torella

Fisher

McWilliams

. Migration of the nellix endoprosthesis. J Vasc Surg. 2016;64(2):306–312.

22.

Swaelens

Poole

Torella

McWilliams

England

Fisher

. Type IIIb endoleak and relining: a mathematical model of distraction forces. J Endovasc Ther. 2016;23(2):297–301.

23.

Casciaro

Alfonso

Craiem

Alsac

El-Batti

Armentano

. Predicting the effect on pulse wave reflection of different endovascular repair techniques in abdominal aortic aneurysm using 1D patient-specific models. Health and Technology. 2016;6(3):173–179.

24.

Boersen

van den Ham

Heyligers

. Validation of pre-procedural aortic aneurysm volume calculations to estimate procedural fill volume of endobags in endovascular aortic sealing. J Cardiovasc Surg (Torino). 2017;58(5):674–679.

25.

Cheng

Cheung

Chan

. Early enlargement of aneurysmal sac and separation of endobags of nellix endovascular aneurysm sealing system as signs of increased risk of later aneurysm rupture. Cardiovasc Intervent Radiol. 2016;39(11):1654–1657.

26.

Frauenfelder

Lotfey

Boehm

Wildermuth

. Computational fluid dynamics: hemodynamic changes in abdominal aortic aneurysm after stent-graft implantation. Cardiovasc Intervent Radiol. 2006;29(4):613–623.

27.

Kleinstreuer

. Fluid–structure interaction effects on sac-blood pressure and wall stress in a stented aneurysm. J Biomech Eng. 2005;127(4):662–671.

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