Ascending aortic volume: A feasible indicator for ascending aortic aneurysm elective surgery?

Area of Science:

• Cardiovascular Research
• Biomedical Engineering
• Medical Imaging

Background:

• Ascending thoracic aortic aneurysm (ATAA) management traditionally relies on diameter-based criteria for preventive surgery.
• Growing evidence suggests diameter alone is insufficient for accurately assessing ATAA rupture risk.
• Patient-specific morphological and hemodynamic factors are increasingly recognized as crucial for risk stratification.

Purpose of the Study:

• To investigate the relationship between hemodynamic conditions and morphological parameters in ATAA.
• To evaluate ascending aortic volume (AAV) as a potential risk indicator for ATAA.
• To compare the predictive value of AAV against traditional diameter-based metrics.

Main Methods:

• Fluid-structure interaction (FSI) analysis was performed on 100 patient-specific ATAA geometries.
• Hemodynamic parameters (e.g., oscillatory shear index, particle residence time) and wall stress were simulated.
• ATAA geometries were classified based on AAV, and parameters were compared between groups.

Main Results:

• Enlarged ATAAs exhibited significantly compromised hemodynamic conditions and elevated mechanical wall stress.
• Key parameters like maximum oscillatory shear index (OSI), particle residence time (PRT), and wall stress (WS) were significantly higher in enlarged ATAAs.
• Ascending aortic volume (AAV) demonstrated a stronger correlation with adverse hemodynamic parameters (e.g., average WS, r=0.92) than maximum diameter.

Conclusions:

• Ascending aortic volume (AAV) may be a more effective risk identifier for ATAA than maximum diameter alone.
• Incorporating AAV into surgical guidelines could improve the prevention of severe aortic events like dissection or rupture.
• Patient-specific FSI analysis provides valuable insights into ATAA biomechanics and rupture risk.