Patient-specific simulation of stent-graft deployment in type B aortic dissection: model development and validation

Area of Science:

• Biomedical Engineering
• Computational Mechanics
• Cardiovascular Surgery

Background:

• Thoracic endovascular aortic repair (TEVAR) is standard for type B aortic dissection.
• Post-TEVAR complications arise from unknown stent-graft (SG) configuration and biomechanics.
• Personalized computational simulation can aid pre-surgical planning.

Purpose of the Study:

• To develop a virtual SG deployment simulation framework for TEVAR.
• To incorporate patient-specific anatomy, SG design, and material properties.
• To validate simulation accuracy against clinical data.

Main Methods:

• Developed a virtual SG deployment simulation framework.
• Utilized patient-specific CT angiographic data and mechanical properties of aorta and SG.
• Determined hyperelastic material parameters from patient tissue samples.
• Accounted for aortic wall pre-stress and blood pressure.

Main Results:

• Simulated post-TEVAR configuration showed good agreement with follow-up CT scans (5.8% deviation in open area, 4.6 mm in strut position).
• SG deployment altered stress distribution, increasing it in the true lumen and decreasing it in the entry tear region.
• Accurate prediction of SG deformation requires including aortic wall pre-stress and blood pressure.

Conclusions:

• The developed simulation framework is a valuable tool for pre-surgical planning in TEVAR.
• Accurate biomechanical modeling is crucial for predicting post-TEVAR outcomes.
• Personalized simulations can help mitigate TEVAR-related complications.