Finite Element Simulation of the Three-Dimensional Residual Stress Field Using a Patient-Specific Aortic Model

Residual stress (RS) in the aorta, key to the in vivo stress distribution, plays a significant role in aortic physiology and pathology. However, quantification of the three-dimensional (3D) residual stress field is challenging because its distribution is patient-specific and heterogeneous. In this study, a stress-driven anisotropic growth model is proposed to qualitatively predict the 3D residual stress field in a patient-specific human aortic wall model. The 3D residual stress field is predicted under the condition that the in vivo stress state is achieved. The in vivo stress is adjusted using the transmural stress heterogeneity. Virtual opening angle tests demonstrate that the simulated opening angles vary between axial positions, and the opening angles peak at the aortic arch. Lateral bending of the axial strips is also simulated. The results of both tests show good agreement with the experimental results in the literature. A parametric study reveals that both the opening and lateral bending angles vary with the in vivo transmural stress heterogeneity. The proposed method can be applied to predict patient-specific 3D heterogeneous residual stress and in vivo stress fields to explore the pathogenesis and treatment of aortic disease.