Hemodynamics in stented vertebral artery ostial stenosis based on computational fluid dynamics simulations

Area of Science:

• Biomedical Engineering
• Cardiovascular Research
• Medical Imaging

Background:

• Vertebral artery ostial stenosis (VAOS) can lead to posterior circulation transient ischemic attacks.
• In-stent restenosis (ISR) is a potential complication after intervention for VAOS.
• Hemodynamic factors are implicated in the development of ISR.

Purpose of the Study:

• To investigate the impact of stent protrusion length on local hemodynamics in VAOS.
• To determine the optimal stent implantation strategy to minimize ISR risk.

Main Methods:

• 3D reconstruction of the vertebral artery from CTA images.
• Computational fluid dynamics (CFD) simulations using finite element analysis.
• Comparison of hemodynamic parameters (blood flow velocity, wall shear stress) across five models with varying stent protrusion (0-3mm).

Main Results:

• Stent implantation significantly reduced WSS (85.33%) and blood flow velocity (35.36%) at the ostium.
• Helical flow patterns were eliminated post-stenting.
• A 1mm stent protrusion resulted in the least reduction in blood speed and WSS compared to other protrusion lengths.

Conclusions:

• Stent implantation can positively alter VAOS hemodynamics.
• A 1mm stent protrusion may mitigate thrombogenesis and neointimal hyperplasia.
• Optimal stent protrusion may reduce the risk of ISR in VAOS patients.