Related Experiment Video
Updated: Jul 15, 2026
11:00
Experimental Investigation of Secondary Flow Structures Downstream of a Model Type IV Stent Failure in a 180° Curved Artery Test Section
Published on: July 19, 2016
Computational fluid dynamics within bifurcated abdominal aortic stent-grafts
Benjamin A Howell1, Tom Kim, Angela Cheer
1Division of Vascular Surgery, University of California at San Francisco, California 94143, USA.
Summary
Hemodynamic forces on abdominal aortic stent-grafts are primarily pressure-related, not flow-related. Stent-graft design and aneurysm sac pressure significantly influence these forces, impacting device performance.
Area of Science:
- Biomedical Engineering
- Cardiovascular Research
- Medical Device Design
Background:
- Abdominal aortic aneurysms (AAAs) are often treated with endovascular repair using stent-grafts.
- Understanding the forces acting on these grafts is crucial for optimizing their long-term performance and patient outcomes.
Purpose of the Study:
- To evaluate the hemodynamic forces, including surface pressure and shear stress, on bifurcated abdominal aortic stent-grafts.
- To assess these forces under realistic physiological conditions of flow, blood pressure, and varying sac pressures.
Main Methods:
- Computational fluid dynamics (CFD) simulations were employed.
- Models were based on computed tomography scans from four patients with AAAs treated with bifurcated stent-grafts.
- Analyses considered temporal and spatial variations throughout the cardiac cycle and under different sac pressure conditions.
Main Results:
- Pressure-related forces were substantially larger than flow-related forces across all graft segments and patient cases.
- The bifurcation region of the stent-graft experienced the highest forces.
- Elevated sac pressures, indicative of endoleak or aneurysm enlargement, correlated with reduced transmural pressure and lower pressure-derived forces.
Conclusions:
- Stent-graft design parameters critically influence the magnitude and distribution of forces.
- Aneurysm sac pressure, which is dependent on stent-graft performance, also plays a significant role in the forces experienced by the device.
