Deployment of a digital twin using the coupled momentum method for fluid-structure interaction: A case study for...

Area of Science:

• Biomedical Engineering
• Computational Fluid Dynamics
• Medical Imaging

Background:

• Ascending aorta aneurysm repair typically uses Dacron grafts, which have lower compliance than native tissue, potentially causing adverse hemodynamic changes.
• Digital human twins (DHT) offer a promising in-silico approach to predict patient-specific outcomes and optimize treatment strategies.

Purpose of the Study:

• To develop a digital human twin (DHT) pipeline for the thoracic aorta to evaluate alternative prostheses to Dacron grafts.
• To explore the use of more compliant prostheses for ascending aorta reconstruction.

Main Methods:

• A DHT was created using fluid-structure interaction (FSI) analysis of the thoracic aorta.
• Three patient models were developed: pre-operative, post-operative with Dacron graft, and post-operative with a compliant fibrous prosthesis.
• Magnetic resonance imaging (MRI) data, including 4D flow MRI, were used for geometry reconstruction and boundary condition definition.

Main Results:

• The FSI models showed good agreement with 4D flow data (relative squared errors of 5.28% and 0.33%).
• Both post-surgical scenarios increased wall shear stress (WSS) and strain compared to baseline.
• The virtual compliant graft demonstrated a lower increase in WSS and strain compared to the Dacron graft.

Conclusions:

• Fluid-structure interaction (FSI) analysis facilitates the creation of reliable thoracic aorta DHTs for predicting the hemodynamic impact of different prostheses.
• More compliant fibrous devices show moderate but promising benefits for distal hemodynamics in ascending aorta aneurysm repair.