An improved reduced-order model for pressure drop across arterial stenoses

Area of Science:

• Biomedical Engineering
• Cardiovascular Hemodynamics
• Computational Fluid Dynamics

Background:

• Accurate quantification of trans-stenotic pressure drop is crucial for assessing occlusive arterial disease.
• Fractional Flow Reserve (FFR) is a key hemodynamic index for guiding coronary revascularization decisions.
• Non-invasive methods for FFR evaluation are needed for safer and more cost-effective disease management.

Purpose of the Study:

• To propose a novel reduced-order model for trans-stenotic pressure drop.
• To incorporate a new term accounting for turbulence effects on pressure loss.
• To enhance the accuracy of hemodynamic index calculations for arterial stenosis.

Main Methods:

• Developed a new formulation of a reduced-order model based on theoretical analysis of the Navier-Stokes equation.
• Included a novel term to characterize the contribution of turbulence to pressure loss.
• Validated the model using three-dimensional computational fluid dynamics (CFD) simulations.

Main Results:

• The proposed model demonstrated significantly higher accuracy compared to existing reduced-order models across various stenosis types (symmetric, eccentric) and severities.
• The model accurately predicted pressure drops for mild to severe arterial area reductions.
• FFR calculations using the proposed model achieved zero classification error for positive, negative, and intermediate FFR categories.

Conclusions:

• The novel reduced-order model provides a more accurate estimation of trans-stenotic pressure drop.
• This improved accuracy leads to reliable FFR calculations, aiding in clinical decision-making for coronary revascularization.
• The model offers a promising tool for non-invasive, cost-effective assessment of arterial stenosis.