Abdominal Aortic Aneurysm Endovascular Repair: Profiling Postimplantation Morphometry and Hemodynamics With...

Area of Science:

• Biomedical Engineering
• Cardiovascular Research
• Medical Imaging

Background:

• Endovascular Aneurysm Repair (EVAR) is a minimally invasive alternative to open surgery for Abdominal Aortic Aneurysms (AAAs).
• Postoperative adverse events, including thrombus formation, can necessitate re-intervention and pose risks.
• Understanding the hemodynamic impact of EVAR devices is crucial for assessing risks and improving outcomes.

Purpose of the Study:

• To investigate the impact of two commercial endovascular grafts on local hemodynamics after EVAR.
• To assess hemodynamic features associated with thrombus formation and compare them to healthy subjects.
• To analyze forces acting on endovascular devices and their relationship with aortic geometry.

Main Methods:

• Utilized 20 image-based computational hemodynamic models (10 per graft type) of EVAR-treated patients.
• Quantitatively assessed hemodynamic features like flow separation and recirculation.
• Complemented hemodynamic analysis with geometrical characterization of the infrarenal abdominal aorta and calculated displacement forces (DFs).

Main Results:

• Established a link between local hemodynamics and the propensity for thrombus formation in EVAR devices.
• Identified strong associations between prothrombotic hemodynamic structures and postoperative aortoiliac tract geometry.
• Found that displacement forces acting on grafts correlate with the cross-sectional area of the postoperative aortoiliac tract.

Conclusions:

• The study explains thrombus formation in EVAR using computational hemodynamics and image-based models.
• Postoperative aortic geometry significantly influences hemodynamics and associated risks.
• Recommends incorporating geometric analysis of implant regions in future clinical follow-ups to monitor shape variations and potential hemodynamic disturbances.