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arXiv · 1704.07753

Fluid-structure interaction modelling and stabilisation of a patient-specific arteriovenous access fistula

W. P. Guess·B. D. Reddy·A. McBride·B. Spottiswoode·J. Downs·T. Franz
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Abstract

A patient-specific fluid-structure interaction (FSI) model of a phase-contrast magnetic resonance angiography (PC-MRA) imaged arteriovenous fistula is presented. The numerical model is developed and simulated using a commercial multiphysics simulation package where a semi-implicit FSI coupling scheme combines a finite volume method blood flow model and a finite element method vessel wall model. A pulsatile mass-flow boundary condition is prescribed at the artery inlet of the model, and a three-element Windkessel model at the artery and vein outlets. The FSI model is freely available for analysis and extension. This work shows the effectiveness of combining a number of stabilisation techniques to simultaneously overcome the added-mass effect and optimise the efficiency of the overall model. The PC-MRA data, fluid model, and FSI model results show almost identical flow features in the fistula; this applies in particular to a flow recirculation region in the vein that could potentially lead to fistula failure.

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W. P. Guess, B. D. Reddy, A. McBride, B. Spottiswoode, J. Downs, T. Franz. 2017-04-25. Fluid-structure interaction modelling and stabilisation of a patient-specific arteriovenous access fistula. https://doi.org/10.1007/s10237-017-0973-8

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