Multi-Modality Imaging Enables Detailed Hemodynamic Simulations in Dissecting Aneurysms in Mice

Area of Science:

• Cardiovascular Research
• Medical Imaging
• Computational Fluid Dynamics

Background:

• Dissecting abdominal aortic aneurysms (DAAAs) are complex vascular diseases.
• Understanding DAAA hemodynamics and lesion progression is crucial for effective treatment.

Purpose of the Study:

• To develop and validate a multi-modality imaging-based modeling approach for studying DAAAs.
• To investigate the relationship between hemodynamics, lesion morphology, and aneurysm evolution in a murine model.

Main Methods:

• Combined in vivo ultrasound and in vitro optical coherence tomography (OCT) for high-resolution geometric and flow data.
• Constructed detailed hemodynamic simulations of murine DAAAs induced by angiotensin II infusion.
• Validated computational models by comparing simulated flows and vortical structures with experimental data.

Main Results:

• Three out of four DAAAs developed thrombus, varying in size.
• A lesion without thrombus showed thickened vessel walls, detectable by OCT and histology.
• Computed flow and vortical structures correlated with differences in lesion size and composition.

Conclusions:

• Coupled high-resolution imaging and computational modeling improve geometric models for DAAA simulations.
• Hemodynamic perturbations are linked to the heterogeneity observed in aneurysmal disease.
• Morphology and hemodynamics are critical determinants in the progression of dissecting abdominal aortic aneurysms.