ARUP; ISBN: 978-0-9562121-5-3 - CMBBE 2012 - Cardiff University

Figure 6. Constant-life diagram for cyclic pressure and axial compression (5%) loads applied to the stent
after its deployment in the atherosclerotic SFA model. The data represented refer to mean and alternating
strain in the most stressed areas of the stent.
Comparison of axial compression load in different plaque models. Since the negligible
effect of cyclic pressure loading in terms of alternating strain, the comparison between
different stenotic vessel models was made only for axial compression loading. The
results in terms of constant-life diagram are shown in Figure 7.
Figure 7. Constant-life diagram for cyclic axial compression (5%) load applied to the stent, after its
implant in 3 different stenotic vessel models. The data represented refer to mean and alternating strain in
the most stressed areas of the stent.
The comparison between the different plaque models reveals that εm values are
comparable as determined by the oversizing ratio, which is essentially the same in all
the cases analyzed. The maximum value of εa is always found at the connection between
link and v-strut (as showed in Fig. 5b) and is always located where the thickness of
vessel-plaque system is less, due to the same reason described above. For every plaque
model the pairs of values (εm; εa) are below the limit curve of the material, suggesting
that the stent is reasonably safe under this loading condition. Despite the maximum
alternating strain values are comparable in all the cases, the more critical configuration
seems to be the one with a double peak plaque: the pairs of values highlighted by the