A one-dimensional arterial network model for bypass graft assessment

Area of Science:

• Biomedical Engineering
• Computational Fluid Dynamics
• Vascular Surgery

Background:

• Arterial occlusive diseases, such as right iliac artery stenosis, significantly impair blood circulation.
• Vascular surgical bypass grafts are crucial for restoring blood flow in patients with arterial blockages.
• Understanding graft performance under varying stenosis degrees is vital for surgical planning.

Purpose of the Study:

• To evaluate the hemodynamic performance of different vascular bypass grafts (Aorto-Femoral, Axillo-Femoral, cross-over Femoral) in a simulated right iliac artery stenosis.
• To analyze the impact of graft material properties (Young's modulus, radius) on hemodynamic outcomes, specifically for Axillo-Femoral bypass.
• To validate a 1D hemodynamic model for assessing bypass graft viability and optimizing surgical interventions.

Main Methods:

• Development of a 1D hemodynamic model based on established fluid dynamics equations.
• Numerical simulations of three distinct bypass graft configurations subjected to varying degrees of right iliac artery stenosis.
• Parametric analysis of the Axillo-Femoral bypass graft by systematically varying its Young's modulus and radius.

Main Results:

• All investigated bypass grafts (Aorto-Femoral, Axillo-Femoral, cross-over Femoral) demonstrated efficient restoration of healthy hemodynamics downstream of the stenosis.
• A global healthy circulation was maintained across all simulated bypass graft scenarios.
• The study identified that the Young's modulus and radius of commercial bypass grafts are hemodynamically optimal.

Conclusions:

• The proposed 1D hemodynamic model accurately simulates bypass graft performance in arterial stenosis.
• The model can be utilized for patient-specific surgical planning and numerical assessment of bypass graft viability.
• Extensive simulations facilitate parametric analysis and error propagation evaluations for improved surgical outcomes.