| Περίληψη: | Cardiovascular diseases are a group of disorders of the heart and blood vessels. Globally, CVDs are
the leading cause of death and serious illness, taking an estimated 17.9 million lives each year. To put
things in perspective, this figure is interpreted into a total of 31% of all deaths worldwide. The
treatment of coronary and peripheral artery disease using metallic stents has been one of the most
revolutionary and most rapidly adopted medical interventions of our time. In the present study, a brief
reference is made to vascular endoprosthesis - stents and their evolution. Next, the range of materials
used, and their geometric characteristics are highlighted, in combination with the influence of these
parameters on the behavior of the stent itself as well as the artery.
Then, the stent of Rontis corporation is constructed using as a prototype the units provided by the
company, while in collaboration with members from the R&D department of the company, its
mechanical properties are verified through simulation in finite element analysis. Subsequently, the
behavior of the stent during its compression and expansion is simulated and investigated, changing
certain parameters, in order to validate the constructed geometry. At the same time, a case of critical
limb ischemia is selected from a patient, and the three-dimensional geometric model at a curved point
of the iliac artery in which atherosclerotic plaque has developed is extracted from the tomography of
the case. Consequently, after processing the 3D model, part of it is inserted assembled together with
the stent into a finite element program and the process of its expansion in a quasi-static analysis is
simulated. Finally, the fatigue cycles needed to occur until the stent failure were calculated under cyclic
loading which is caused by the alteration between systolic and diastolic pressure.
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