Stent biomaterial and design selection using finite element analysis for percutaneous aortic valve replacement

Vascular support structures are important devices for treating valve stenosis. Large populations of patients are treated for valvular disease and the principal mode of treatment is the use of percutaneous valvuloplasty. Stent devices are proving to be imperative in minimally invasive cardiac surgery. This new technology provides highly effective results at minimal cost and short duration of hospitalization. This article discusses the finite element analysis (FEA) of various percutaneous aortic valve stent designs. The stent designs were modeled and subjected to FEA. Analysis was done on four models using three biomaterials, with loads ranging from 10,665.8 N/m(2) to 26,664 N/m(2). These pressures were selected as they are equivalent to human blood pressure, which ranges from 80 mm Hg to 200 mm Hg. They were also selected to understand the mechanical behavior of different stent designs under such high pressures. Four stent models were generated and their physical, mechanical, and behavioral properties were studied. FEA and simulation of these models encouraged the designer to select the geometry and the biomaterial suitable for performance during and after implantation. The analysis performed in this article may aid in understanding the stents' performance ranges when subjected to the physiological pressures exerted by the heart and cardiac blood flow during abnormal cardiovascular conditions. It may also help in finding the best design and the biomaterial that would be suitable under such conditions.