A comparison between fractured Xience-like and Palmaz-like stents using a novel computational model

Annu Int Conf IEEE Eng Med Biol Soc. 2009;2009:1106-8. doi: 10.1109/IEMBS.2009.5334427.


We developed a novel mathematical model to study the mechanical properties of endovascular stents in their expanded state. The model is based on the one-dimensional theory of slender curved rods. Stent struts are modeled as linearly elastic curved rods that satisfy the kinematic and dynamic contact conditions at the vertices where the struts meet. A Finite Element Method for a numerical computation of its solution was developed and used to study mechanical properties of two commonly used coronary stents (Palmaz-like and Xience-like stent) in their expanded, fractured state. A simple fracture (separation), corresponding to one stent strut being disconnected from one vertex in a stent, was considered. Our results show a drastic difference in the response of the two stents to the physiologically reasonable uniform compression and bending forces. In particular, deformation of a fractured Xience-like stent (with one strut separated from one vertex) is significantly larger than that of a fractured Palmaz-like stent when exposed to uniform compression and bending. This presents conditions which may be a precursor for the clinically observed complications associated with in-stent thrombosis and in-stent restenosis of fractured coronary stents.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Biomechanical Phenomena
  • Biomedical Engineering
  • Elasticity
  • Equipment Failure Analysis / methods*
  • Equipment Failure Analysis / statistics & numerical data
  • Finite Element Analysis
  • Humans
  • In Vitro Techniques
  • Models, Theoretical
  • Prosthesis Design
  • Prosthesis Failure*
  • Stents*