A patient-specific CTA-CFD framework deciphers hemodynamic heterogeneity after fenestrated TEVAR: a pilot study

Area of Science:

• Cardiovascular Surgery
• Biomedical Engineering
• Medical Imaging

Background:

• Clinical outcomes of fenestrated thoracic endovascular aortic repair (TEVAR) show significant variability.
• The underlying hemodynamic mechanisms contributing to this heterogeneity are not well understood.

Purpose of the Study:

• To develop and validate a patient-specific computational framework.
• Integrate computed tomography angiography (CTA) and computational fluid dynamics (CFD) to analyze morpho-hemodynamic changes after fenestrated TEVAR.

Main Methods:

• Reconstructed 3D aortic geometries from postoperative CTA in six patients undergoing TEVAR with LSA fenestration.
• Performed high-fidelity CFD simulations to assess flow distribution, velocity, time-averaged wall shear stress (TAWSS), and oscillatory shear index (OSI).

Main Results:

• The brachiocephalic trunk showed minimal impact (median ARBT 0.80).
• Identified severe LSA stenosis (ARLSA = 5.25) and mild LCCA compromise (ARLLCA = 1.27) with elevated TAWSS.
• One patient had inadequate descending aorta flow (42.83% cardiac output); others had no significant hemodynamic abnormalities.

Conclusions:

• Established a patient-specific CTA-CFD framework to analyze post-TEVAR morpho-hemodynamic alterations.
• The methodology quantitatively links geometric changes to adverse hemodynamic phenotypes, offering insights into outcome disparities.
• This computational tool requires further validation in larger prospective studies.