Blood Flow in the Abdominal Aorta Post 'Chimney' Endovascular Aneurysm Repair

Abstract

Aortic aneurysms are a main death cause in the elderly population throughout the western world. In recent years, more aneurysm repairs are performed endovascularly using stent grafts (SGs) inserted into the aneurysm site through the arterial system (minimally invasive). In this study, we analyze the hemodynamics in an aneurysmatic abdominal aorta (AAA) endovascularly repaired by a stent graft (SG) system using the chimney technique. Computational fluid dynamics (CFD) is employed to study models of a healthy aorta versus an aorta post 'chimney' endovascular aneurysm repair (ChEVAR) using chimney stent grafts (CSG) inserted into each renal artery in parallel to the aortic SG. Results demonstrate that the presence of the CSGs results in stagnation regions and wall shear stress (WSS) modifications, yet the flow regime remains laminar. Thus, indicating the spatially contained effects of the ChEVAR technique and further supporting its merit.

The effect of stent graft curvature on the hemodynamic displacement force after abdominal aortic aneurysm endovascular repair

“…[19][20][21][22]. Other studies dealt with the qualitative relationship of geometric parameters with the DF [12][13][14][15][16][17], proposing hypotheses linking geometric parameters and DF but not quantitatively. It can still be seen that the DF values obtained in this study (3-7 N) are in good agreement with other studies [19,21,24,25,33] and more.…”

“…Computational mechanics models can assist in accurately assessing the artery's condition after SG insertion [9][10][11]. The effect of different geometric parameters on EVAR results was previously investigated using numerical methods, including parameters such as chimney length [12,13], SG oversizing, aortic neck calcification [14], aneurysm neck angle [15] and SG bifurcation geometry [16,17]. Displacement force was calculated in computational fluid dynamics (CFD) studies, with both representative anatomies [18,19] and patient-specific geometries [20][21][22].…”

Analysis of Postoperative Remodeling Characteristics after Modular Inner Branched Stent-Graft Treatment of Aortic Arch Pathologies Using Computational Fluid Dynamics

“…As discussed above, after the treatment of AAPs, the morphologies of the aortic arch change significantly, which alters the existing flows. This provides a clue for the assessment of different treatment approaches before operation [13,20,22,23,26,28].…”

“…While the blood flow field has important physiological meanings, it is attractive to extract an "ideal" structure from real tissues to study the effects of the predominant structure characteristics only [26,27]. This approach is significant for the understanding of typical flow patterns in tissues, such as secondary flow and helical flow.…”