Backround: Currently, the effect of vascular dynamic bending (VDB) has not been\nfully considered when studying cardiovascular stents� long-term mechanical properties,\nas the previous studies about stent�s mechanical properties mostly focus on the effect\nof vascular pulsation (VP). More and more clinical reports suggested that the effect of\nVDB have a significant impact on stent.\nMethods: In this paper, an explicit-implicit coupling simulation method was applied\nto analyze the mechanical responses of cardiovascular stents considering the effect of\nVDB. The effect of VP on stent mechanical properties was also studied and compared\nto the effect of VDB.\nResults: The results showed that the dynamic bending deformation occurred in stents\ndue to the effect of VDB. The effects of VDB and VP resulted in alternating stress states\nof the stent, while the VDB alternate stresses effective on the stent were almost three\ntimes larger than that of the VP. The stress concentration under VDB mainly occurred\nin bridge struts and the maximal stress was located in the middle loops of the stent.\nHowever, the stress distributed uniformly in the stents under the effect of VP. Stent\nfracture occurred more frequently as a result of VDB with the predicted fracture position\nlocated in the bridging struts of the stent. These results are consistent with the\nreported data in clinical literatures. The stress of the vessel under VDB was higher, than\nthat caused by VP.\nConclusions: The results showed that the effect of VDB has a significant impact on the\nstent�s stress distribution, fatigue performance and overall stress on the vessel, thus it is\nnecessary to be considered when analyzing stent�s long-term mechanical properties.\nMeanwhile, the results showed that the explicit-implicit coupling simulation can be\napplied to analyze stent mechanical properties.
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