Sensitivity Analysis of the Boundary Conditions in Simulations of the Flow in an Aortic Coarctation under Rest and Stress Conditions

Abstract

Aortic coarctation is a congenital condition in which the aorta is narrowed. The pressure drop through the aorta depends on the extension of this narrowing. Therefore, severe coarctations have important side-effects on the hemodynamic conditions of the circulatory system. The Computational Fluid Dynamics (CFD) simulation of the hemodynamics in a patient specific aortic coarctation can help to predict the pressure drop produced by the aorta narrowing. Nevertheless, an accurate prediction of the pressure drop, by means of CFD tools, depends strongly on the boundary conditions (BCs). In this study we present the results of ten simulations performed on a patient specific aortic coarctation vasculature proposed in the second MICCAI-STACOM CFD Challenge. The model includes ascending aorta, arch, descending aorta, and upper branch vessels. Specifically, we consider; two different physiological states a) rest and b) stress condition. For both cases the flow rate waveforms are provided at the ascending aorta and descending aorta. The ten simulations are performed using five different set of boundary conditions. The results are reported and indications on the more accurate boundary conditions are discussed.