Endovascular Stent Graft Design
Endovascular repair of the aorta is associated with reduced morbidity compared to open repair. However, a long term complication can be thrombosis of the stent graft, necessitating open removal of the stent graft and aortic replacement. This project developed in vitro methods that incorporated both mechanics and biology to predict the potential for development of thrombosis in endovascular stent graft designs.
The project incorporated three primary parts:
- A physical, in vitro system was developed that allowed the deployment of a stent graft and simulation of blood flow and platelet activation. Zymetrix assisted with the design of experiments to examine blood coagulation and platelet involvement, and conducted blood analysis.
- A novel system was developed to simulate the effect of blood on the detailed geometry of the stent graft. Zymetrix then imaged the stent graft in a micro CT and developed a 3D high resolution geometric model in Simpleware.
- A 3D computational fluid dynamics (CFD) model was developed and validated against the physical system The CFD model identified wall shear stress as a strong indicator of thrombotic potential.