Characterization of arterial flow mediated dilation via a physics-based model.

Abstract

In this paper, a physics-based mathematical model is developed to describe the transient behavior of the brachial artery during the Flow Mediated Dilation (FMD) test. The change of the artery's diameter was collected for 7 cases via in vivo, non-invasive ultrasound imaging. A theoretical model was developed to capture the response of the blood vessel to the change of the blood flow, in which the vessel's compliance is modeled as a function of the wall shear stress (WSS). The theory precisely captures the key feature of the mechanotransduction process, which a conventional viscoelastic model fails to describe. Three characteristic dimensionless parameters were obtained from the model, quantifying the physical state of the artery and related to the cardiovascular health. The transient physics, manifested in the two-way (where both arterial compliance and blood flow conditions affect each other) Fluid-Structure Interaction (FSI) process, present an interesting opportunity to explore the nature of living materials making up the arterial walls, which would in turn lead to a better understanding and therefore detection of the onset of some forms of cardiovascular diseases (CVD).