Compilation of assessment criteria for evaluating mechanical performance of SG candidates included in this study. a Maximal Von Mises Stress of stent ( max S ) , b maximal longitudinal membrane strain max LG , c maximal circumferential membrane strain max CG , d maximal

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... modeling strategy and choice of elements for the stent and FEM software used. Next, the results for all SG candidates are presented in terms of their global deformation properties in Fig. 4, maximal LR, maximal stresses in the stent, maximal strains in the graft, and torque-bending angle behavior observed during their respective performances in Fig. ...

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... into consideration the maximal stresses presented in Fig. 5a, we can categorize the SG candidates into two distinct groups. Group 1 includes AO-LP and CRE-DIA, both of which exhibit max S values less than 250 MPa. In contrast, Group 2 encompasses the remaining stents, which display max S values falling within the range of 250 to 320 MPa. ...

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... the candidates depicted in Fig. 5b [16], a consistent observation across all SG candidates was that the peak fabric strains were most prominent on the inner curvature of the SG, particularly between the stent rings (stent spacing) or between individual stent peaks. This occurrence is influenced by the overlapping of stent struts in these specific areas. ...

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... the novel SG candidates originating from auxetic unit cells or NUPR unit cells, all exhibited a LR max magnitude below 12% in Fig. 5d, suggesting their suitability for clinical applications. Within this group, AO-LP, CRE-DIA, and CS-DIA emerged as the only candidates with LR max values below 6%. As expected with the observed kink in its central region, ZLP8 displayed the highest LR max magnitude among all SG candidates, approaching 45%, which is in proximity to the ...

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... to the torque-angle curves presented in Fig. 5e, AO-LP emerges as the most flexible SG candidate, as it exhibits a peak torque of less than 2 N mm. ZLP8 and CRE-DIA closely follow in terms of flexibility, with torque values of 5 N mm and 12 N mm, respectively. It's worth noting that AO-LP maintains a consistent and stable torque curve behavior throughout a 180° angulation, a ...

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... mm, respectively. It's worth noting that AO-LP maintains a consistent and stable torque curve behavior throughout a 180° angulation, a distinctive characteristic when compared to the novel SG candidates derived from auxetic unit cells. The latter exhibit a relatively linear increase in torque magnitude in the range of 60° to 120°, as depicted in Fig. 5e. In the case of ZLP8 (Fig. 4), the formation of kinks in the central region is associated with the torque increase observed between 80° and 150° of angulation. The oscillation seen in the torque-angle curves of SG candidates derived from auxetic unit cells can be attributed to graft wrinkling when being pulled inward by the stents ...

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... that SGs employing circular, spiral, or Z-spiral stents showcased enhanced flexibility compared to standard Z-stented SGs like Zenith-LP. This distinction is evident in Fig. 4, which depicts a noticeable kink in the central area of ZLP8. Importantly, none of the SGs in our study displayed stress magnitudes exceeding 390 MPa, as depicted in Fig. 5a. This indicates that the nitinol stents retained their elastic properties throughout the simulation, suggesting that the novel SGs are unlikely to experience stent fractures, as they did not approach the ultimate strength of nitinol (1172 MPa). Demanget et al. [16] also noted that none of the SGs in their research exhibited graft ...

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... suggesting that the novel SGs are unlikely to experience stent fractures, as they did not approach the ultimate strength of nitinol (1172 MPa). Demanget et al. [16] also noted that none of the SGs in their research exhibited graft strains surpassing 20% (which is the ultimate strain limit for PET), a finding consistent with our study, as shown in Fig. 5b, c. This reaffirms that the novel SGs exhibit satisfactory reliability in terms of both the stent and graft components when subjected to high tortuosity ...

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... the context of flexibility, all the novel SGs displayed values considerably below the critical luminal reduction threshold of 60%, as evident in Fig. 5d. This substantiates the suitability of these SGs for EVAR applications, particularly in situations involving intricate iliac angulations with high tortuosity. Notably, AO-LP (a circular-stented SG) exhibited superior flexibility, a characteristic consistent with the findings reported in Demanget et al. [14], as indicated by the torque ...

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... the suitability of these SGs for EVAR applications, particularly in situations involving intricate iliac angulations with high tortuosity. Notably, AO-LP (a circular-stented SG) exhibited superior flexibility, a characteristic consistent with the findings reported in Demanget et al. [14], as indicated by the torque vs. angle curves in Fig. 5e. As an additional evaluation, we assessed the radial properties of the novel SG candidates by comparing them to ZLP8 through a crimp test involving a single stent ring, the results of which are presented in Fig. 6. All the novel stents exhibited strain magnitudes at the crimped diameter (corresponding to a 60% reduction in stent ...