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FIG 4. Arterial bifurcation with saccular aneurysm.
A, Instantaneous velocity vector plot of flow in arterial bifurcation model with saccular aneurysm during deceleration portion of systole.
B, Continuous particle paths for t* = 200–400 for arterial bifurcation model with saccular aneurysm. Initially the particles were aligned across the lumen of the parent artery.
C, Instantaneous pressure contours for arterial bifurcation model with saccular aneurysm during deceleration portion of cardiac systole (t* = 245). Plot corresponds to time of maximal pressure at bifurcation. For reference purposes, contour A corresponds to a value of -0.308 dpu (dimensionless pressure units) whereas contour O corresponds to a value of 1.535 dpu.
D, Line plot of instantaneous pressure along arterial wall corresponding to figure 4C. Shown is the pressure along arterial wall and aneurysm dome from node 2189 to node 2231. Location of maximal pressure corresponds to location of stagnation point at aneurysm neck site N1.
E, Pressure time history plot for arterial bifurcation model with saccular aneurysm over one cardiac cycle. Curve A corresponds to the vessel inlet, Curve B corresponds to the aneurysm neck site N1 and Curve C corresponds to the aneurysm neck site N2. Note the secondary rise in pressure at the neck N2. This pressure oscillation may give rise to vibrations at the neck site and further increase the chance of structural fatigue.
F, Time history plot of shear rates for arterial bifurcation model with saccular aneurysm at aneurysm necks sites N1 and N2. Curves A and B correspond to aneurysm neck sites N1 and N2, respectively. Note that the shear rate values at N2 exceed those of N1 throughout the entire cardiac cycle.
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