Numerical simulation and in vitro examination of the flow behaviour within coronary stents

This paper discusses the influence of different design parameters of stents by mathematical flow simulations and flow measurements using micro-particle image velocimetry (micro-PIV). A stent strut may cause recirculation areas, which are considered to be the source of thrombosis and the process of in-stent restenosis. The simulations showed that a reduced strut height and a chamfering of the struts reduce these recirculation zones. The numerically determined results were compared with experimental investigations. For this purpose metallic stent structures were transferred into transparent channel systems made of PDMS. The experimental investigations confirm the results of numerical simulations

The influence of strut-connectors in coronary stents: A comparison of numerical simulations and μPIV measurements

This paper discusses the influence of different designs of strut-connectors of stents by numerical flow simulations and flow examinations using micro particle image velocimetry (μPIV). Many studies have shown that there is a correlation between the hemodynamics after stent implantation and the cause of biological responses like thrombosis and the in-stent restenosis. Recirculation areas may occur through a stent, which are considered to be the cause of these clinical complications. In this study, three different coronary stent designs are investigated and the hemodynamic effects from the different designs is presented. The study focuses on the design of the strut-connectors that connect two struts. Numerical simulations were performed to evaluate various flow features like recirculation zones, velocity profiles and wall shear stress (WSS) patterns. To verify the numerical results μPIVmeasurements were performed. It could be shown that the alignment in the main stream of the connectors influences the size and number of recirculation zones