Admedes Schuessler GmbH

Fluid-structure interaction transient simulation of aortic valve taking into account stent crimping and release against the aortic wall

Problem:

The interaction of blood, stent and aorta are critically importance in determining accurate stress cycles in Nitinol self-expanding stent implants. These factors could improve stent lifetime.

Solution:

Admedes Schuessler and CADFEM (Suisse) developed a modeling procedure with a set of important steps:

  • Stent crimping
  • Stent release against the aortic wall
  • Fluid-structure two-way coupled transient simulation using mesh morphing and remeshing

The team considered a number of factors, including frictional contacts between stent and wall, shape memory alloy, pericardium valve orthotropic properties and non-newtonian blood.

Business Benefit:

Simulation provided unprecedented information levels — not available with experimental measurements. These revealed the evolution of forces and stresses during a heart pulse and the effects on working conditions, integrity and lifetime of the stent.

Software used:

  • ANSYS Fluent
  • ANSYS Mechanical