Finite element modeling of the thoracic aorta: including aortic root motion to evaluate the risk of aortic dissection

Abstract

Objective: We propose that the aortic root motion plays an important role in aortic dissection.

Methods and results: A finite element model of the aortic root, arch and branches of the arch was built to assess the influence of aortic root displacement and pressure on the aortic wall stress. The largest stress increase due to aortic root displacement was found at approximately 2 cm above the top of the aortic valve. There, the longitudinal stress increased by 50% to 0.32 MPa when 8.9 mm axial displacement was applied in addition to 120 mmHg luminal pressure. A similar result was observed when the pressure load was increased to 180 mmHg without axial displacement.

Conclusions: Both aortic root displacement and hypertension significantly increase the longitudinal stress in the ascending aorta, which could play a decisive role in the development of various aortic pathologies, including aortic dissection.