Biomechanical patient-oriented analysis of influence of the aneurysm on the hemodynamics of the thoracic aorta

The aim of the study was biomechanical modeling of the development and influence of thoracic aortic aneurysm on the hemodynamics of the vessel. Aortic aneurysm is an irreversible expansion of the aorta and is one of the diseases of the cardiovascular system with a high fatal outcome. Biomechanical modeling included: setting the task, building a virtual model of the object under study, setting boundary and initial conditions and properties of materials, also assessment the results of a numerical experiment based on the physiological characteristics of the object. Two three-dimensional virtual models of the thoracic aorta were constructed on the basis of computed tomographic angiography of a real patient: with an aneurysm of the ascending division and after prosthetics. To analyze the development of pathology, were created additional virtual models with different degrees of aneurismal expansion. The calculation is carried out taking into account the parameters characterizing the work of the cardiovascular system (blood pressure value, dynamic viscosity and blood density). The analysis of the results showed a change in the character of blood flow, the formation of region of blood stagnation in the aneurysm zone. It was revealed that with the increase in the geometric dimensions of the pathology there is a drop in the blood flow rate and an increase in the flow pressure values in the aneurysm. Asymmetric distribution of pressure values on the inner surface of the aorta, triggered by the displacement of the flow velocity vector relative to the axis of the blood vessel, can to incite further development of an aneurysm.