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Currently, stent therapy constitutes to over 95% of all endovascular interventions
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The biological and clinical complications of stent therapy can now be well controlled
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Mechanical failure remains an important clinical problem
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The failure usually proceeds through mechanical fracture activation due to fatigue
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The virtual analysis of fracture is typically conducted using the Finite Element Method (FEM)
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Sunergolab Inc. pursue an alternative approach, called Peridynamics
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Peridynamic damage model does not require special criteria to guide damage growth and naturally accounts for surface roughness that can highly influence the fatigue life of stent
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Sunergolab's peridynamic solver exploited in this study explicitly resolved stent fracture initiation and the underlying mechanical force resulting from clinically observed stent deformation

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Initial CAD geometry of the patient-specific stent is a courtesy of Prof. Bressloff
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This CAD geometry accounts for a stent deformation due to interactions with the walls of coronary artery
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Time harmonic displacement (Dirichlet) boundary conditions were applied to the edges of the stent to induce fatigue damage
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An accumulated longitudinal tension was found
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The stent geometry preserved main shape features during the stimulated tension
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Fatigue damage due to accumulated longitudinal tension in the patient-specific stent does not propagate far from the deformed edges
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The fatigue damage peaks at the connecting struts of the patient-specific stent

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Credit/acknowledgement: The turbine blades geometry is the courtesy of Prof. Bressloff (Ragkousis et al., 2014, “Simulation of longitudinal stent deformation in a patient-specific coronary artery”, Medical Engineering & Physics, 36(4), pp. 467-476)