Study of a Nitinol stent deployed into anatomically accurate artery geometry and subjected to realistic service loading

Finite element analysis is commonly used to assess the structural behavior of a stent during deployment and service loading. Most of these studies use simplified boundary conditions, such as a rigid surface to model the artery; however, this does not take into account the compliance of the artery material and ovalization during bending. In order to investigate the effect of these simplified assumptions, we obtained anatomically correct artery geometry from MRI scans, converted the geometry to a finite element mesh, calculated the material parameters of this artery from compliance data, and deployed a stent into this artery. After deployment, we subjected the artery to pulsatile loading by applying systolic and diastolic pressures. These analyses were performed with both a straight and a bent section of the artery. The effect of blood flow through the artery was also investigated. In conclusion, by deploying the stent into actual artery geometry and applying loading that considers the blood flow within the artery, more realistic results of a stent in service loading were obtained. Studies with the bent section of artery could be improved, as the stent was deployed into the bent artery, whereas in reality the artery is straight during deployment and takes the bent shape during service loading. Therefore, more realistic loading in the bent configuration could be a topic of further research.