Resumo (PT):
Abstract (EN):
The present work is about the application of wall shear stress descriptors – time averaged wall
shear stress (TAWSS), oscillating shear index (OSI) and relative residence time (RRT) – to the study
of blood flow in the left coronary artery (LCA). These descriptors aid the prediction of disturbed
flow conditions in the vessels and play a significant role in the detection of potential zones of
atherosclerosis development. Hemodynamic descriptors data were obtained, numerically, through
ANSYS® software, for the LCA of a patient-specific geometry and for a 3D idealized model. Comparing
both cases, the results are coherent, in terms of location and magnitude. Low TAWSS, high OSI and
high RRT values are observed in the bifurcation – potential zone of atherosclerosis appearance. The
dissimilarities observed in the TAWSS values, considering blood as a Newtonian or non-Newtonian
fluid, releases the importance of the correct blood rheologic caracterization. Moreover, for a
higher Reynolds number, the TAWSS values decrease in the bifurcation and along the LAD branch,
increasing the probability of plaques deposition. Furthermore, for a stenotic LCA model, very low
TAWSS and high RRT values in front and behind the stenosis are observed, indicating the probable
extension, in the flow direction, of the lesion.
Language:
English
Type (Professor's evaluation):
Scientific
No. of pages:
13