4438 Comparison of in vivo 3 D flow characteristics to realistic in vitro models with flexible and rigid vessel wall

Purpose: For a better diagnosis and treatment of cardiovascular diseases it is necessary to investigate the cause and relationship between morphological and functional changes of the heart and vessels. In addition to longitudinal in vivo studies, realistic in-vitro model systems of vascular systems such as the aorta have the potential helping to understand the link between progression of vascular diseases (such as aortic coarctation or aneurysms) and their association with complex hemodynamic alterations. Recently, realistic vascular in vitro phantoms in combination with a pulsatile flow circuit and 4D MRI flow measurements were employed to simulate realistic in vivo hemodynamics [1,2]. However, previous vessel models consisted of a rigid material and it is unclear how the absence of vessel wall compliance influenced the resulting 3D blood flow inside the model system. Thus, the aim of this study was to perform in vitro model experiments using realistic vessel models of the thoracic aorta made with a flexible material to investigate the impact of different wall thicknesses (simulating different levels of elasticity) on hemodynamics. Results were compared to in vitro models with rigid vessel walls and to in vivo 3D flow characteristics in the subject's aorta used to generate the in vitro model.