Here is the stent sliced up so that you can get a 3×3 cross-section of linear hex elements. The total number of nodes in the stent is 31,456.

I notice your artery is 3 hex elements through the thickness, which is good. What you should do is use linear element order on the artery. These two meshes will greatly reduce the total number of nodes in the model, which should reduce the solution time.

Download a .wbpz archive file using this link and open it in Workbench.