A multi-scale mechanobiological framework for vibration-induced intimal hyperplasia

Area of Science:

• Biomedical Engineering
• Vascular Biology
• Computational Mechanics

Background:

• Intimal hyperplasia is a key process in vascular diseases, regulated by mechanical forces like wall shear stress (WSS) and circumferential stress.
• Hand-arm vibrations (HAV) are suspected to contribute to intimal hyperplasia in digital arteries through altered WSS.

Purpose of the Study:

• To develop and utilize a mechanobiological framework to investigate the impact of HAV on intimal hyperplasia development.
• To simulate the effects of chronic vibration exposure on digital artery mechanics and cellular processes.

Main Methods:

• Coupling an agent-based model (ABM) for cellular/molecular mechanisms with a finite element model (FEM) for arterial mechanics.
• Incorporating WSS as an input reflecting vibration exposure and computing circumferential stresses.
• Calibrating model parameters using experimental data and literature.

Main Results:

• Simulations over 5 years showed negligible impact of arterial wall constitutive laws on stenosis progression.
• Reduced circumferential stress due to arterial wall thickening promoted ECM degradation via matrix metalloproteinase-2.
• The model successfully estimated vibration-induced stenosis rates.

Conclusions:

• Chronic HAV exposure can induce intimal hyperplasia and stenosis by reducing WSS and altering mechanical stresses.
• The developed mechanobiological framework is a valuable tool for studying vibration-induced vascular pathologies.
• The framework can be adapted for diverse biomechanical and pathological contexts of intimal hyperplasia.