Comparison of Fluid Dynamics Variations Between Chimney and Fenestrated Endografts for Pararenal Aneurysms Repair: A Patient Specific Computational Study as Motivation for Clinical Decision-Making. (October 2019)

• Record Type: Journal Article
• Authors: Moulakakis, Konstantinos G.; Kakisis, John; Gonidaki, Eleni; Lazaris, Andreas M.; Tsangaris, Sokrates; Geroulakos, George; Manopoulos, Christos
• Is Part Of: Vascular & endovascular surgery. Volume 53:Number 7(2019)
• Page Start: 572
• Page End: 582
• Publication Date: 2019-10
• Subjects: computational fluid dynamics -- aneurysm -- pararenal -- endovascular repair -- chimney -- fenestrated; Blood-vessels -- Surgery -- Periodicals; Blood-vessels -- Endoscopic surgery -- Periodicals; Vascular Surgical Procedures -- Periodicals; Angioplasty -- Periodicals; Surgical Procedures, Minimally Invasive -- Periodicals; Vascular Diseases -- surgery -- Periodicals; Vaisseaux sanguins -- Chirurgie -- Périodiques; Vaisseaux sanguins -- Chirurgie endoscopique -- Périodiques; 617.41
• DOI: 10.1177/1538574419867531
• Languages: English
• ISSNs: 1538-5744

Abstract

Background-Aim: Limited data exist concerning the fluid dynamic changes induced by endovascular aortic repair with fenestrated and chimney graft modalities in pararenal aneurysms. We aimed to investigate and compare the wall shear stress (WSS) and flow dynamics for the branch vessels before and after endovascular aortic repair with fenestrated and chimney techniques. Methods: Modeling was done for patient specific pararenal aortic aneurysms employing fenestrated and chimney grafts (Materialise Mimics 10.0) before and after the endovascular procedure, using computed tomography scans of patients. Surface and spatial grids were created using the ANSYS CFD meshing software 2019 R2. Assessment of blood flow, streamlines, and WSS before and after aneurysm repair was performed. Results: The endovascular repair with chimney grafts leaded to a 43% to 53% reduction in perfusion in renal arteries. In fenestrated reconstruction, we observed a 15% reduced perfusion in both renal arteries. In both cases, we observed a decrease in the recirculation phenomena of the aorta after endovascular repair. Concerning the grafts of the renal arteries, we observed in both the transverse and longitudinal axes low WSS regions with simultaneous recirculation of the flow 1 cm distal to the ostium sites in both aortic graft models. High WSS regions appeared in the sites of ostium. Conclusions: We observed reduced renal perfusion in chimney grafts compared to fenestrated grafts, probably caused by the long and kinked characteristics of these devices.