| To improve our understanding of Coronary Artery Disease, much research is focused on understanding wall shear stress and other hemodynamic indices associated with plaque development. Computational fluid dynamics (CFD) is an important tool for quantifying hemodynamics, but often, many assumptions are made when these simulations are performed. For example, most coronary artery models neglect (Steinman, 2001, Wentzel et al. (2003), Wahle et al. 2006) branching when performing CFD analysis. The goal of this study is to determine the threshold size of the branches in the coronary arteries that should be incorporated in geometric reconstruction for the simulation of blood flow. This is performed using patient-specific human coronary arteries, and hemodynamics are computed using a new algorithm that minimizes user intervention for CFD analysis Patient-specific human coronary artery geometry is obtained via a fusion of IVUS and bi-plane angiography images, in which a surface mesh is then generated for CFD analysis using in-house, level-set-based CFD software. Research has suggested that blood flow patterns are highly affected by branch flows, and branching is one of the leading locations of plaque accumulation. In this study, we have examined the role that various branch dimensions play on downstream blood flow in the main branch, to determine what branches could be reasonably neglected, and which must be included for reasonable hemodynamic studies. Secondary flow patterns and wall shear stress were examined at numerous distal locations for differences in blood flow due to branching. Results from this study suggested that presence of branches caused low local axial wall shear stress (TWSS) and reverse flows in the vicinity of branching in both upstream as well as downstream region. The region of impact however depended on the size of the cross section of the artery and of the branch; larger the cross section higher the impact. |
