Applications of FSI for Cardiovascular Haemodynamics - Computational Hemodynamics: Theory, Modelling and Applications - page 275

Fig. 8.39 Maximum principal stress and deformation based on elasticity of three-dimensional
plaque composite and fibrous cap thickness based on non-calcified and calcified plaque. ( a ) maxi-
mum principal stress σ max versus Young's modulus E lp and fibrous cap thickness d fc shows that
critical stress is 350 kPa ( b ) at d cg = 0.02 mm, the plot of σ max versus E cag and d fc shows that critical
stress is 258 kPa ( c ) peak deformation D fc versus E lp and d fc shows that maximum deformation
D max is 0.328 mm. ( d ) D fc versus E cag and d fc gives D max = 0.236 mm

elasticity and fibrous cap thickness (Fig. 8.38c ). Critical stress for a calcified plaque
( σ cr = 268.12 kPa) is lower than that of a non-calcified one. In general, the stress
levels of the calcified plaque are lower than a non-calcified one.
Peak deformation D max at 0.389 mm or 389 μm corresponds to the lower limit
of the range that pertains to lipid core Young's modulus and fibrous cap thickness.
With calcification, D max is reduced to 0.239 mm (Fig. 8.38d ). The overall deforma-
tion is generally lower than that for the non-calcified plaque. The deformations are
an order of magnitude higher than the fibrous cap for plaque rupture.

8.5.4.4 Three-Dimensional Fluid-Structural Analysis

An improvement in smoothness of the surface curve variation was found based on
three-dimensional fluid-plaque simulation in the atherosclerotic carotid bifurcation.
The critical stress for a non-calcified plaque σ cr = 350 kPa (in Fig. 8.39a ) is higher
than that of a calcified one with d cg = 0.1 mm at σ cr = 258 kPa (shown in Fig. 8.39c ).
D max at 0.328 mm corresponds to the maximum deformation for non-calcified
plaque (Fig. 8.39b ). With calcification, D max is reduced to 0.236 mm (Fig. 8.39d ).