Design Methodology of a Balloon Expandable Polymeric Stent

Abstract

In the present work, a finite element-based study is undertaken to evolve a design methodology for developing a polymeric stent. Design steps include (1) crimping a stent cut from a polymer tube having outer diameter of 3 mm to a crimped diameter of 1.6 mm, (2) crimping recoil, (3) deployment of crimped stent to 3.3 mm outer diameter, (4) expansion recoil (mimicking crimping and dilation process to treat a 3 mm inner diameter artery) and (5) recoil under pressure. Effect of stent geometry parameters such as crown radius, length, width and thickness on the performance parameters such as radial strength, parallel plate collapse force, radial stiffness, recoil, foreshortening, maximum stresses, and strains are studied. The parametric study further aims to develop a design methodology for polymeric stent mechanical performance evaluation. The effect of crown shape and connector design on stent performance is discussed. Stent design parameters and material property optimization are reported for a polymeric stent.