Characterization of chemoelastic effects in arteries using digital volume correlation and optical coherence tomography

TL;DR

This study uses optical coherence tomography and digital volume correlation to quantify 3D chemoelastic strains in arteries, revealing the significant role of chemoelasticity in arterial mechanics and its potential impact on vascular health.

Contribution

First-time measurement and analysis of 3D chemoelastic strains in arterial tissues using OCT-DVC, highlighting chemoelasticity's importance in vascular mechanobiology.

Findings

Chemoelastic effects are exacerbated by hyperosmotic solutions.

Swelling of arterial media modifies optical properties.

Transverse tensile strains are induced by chemoelasticity.

Abstract

Understanding stress-strain relationships in arteries is important for fundamental investigations in mechanobiology. Here we demonstrate the essential role of chemoelasticity in determining the mechanical properties of arterial tissues. Stepwise stress-relaxation uniaxial tensile tests were carried out on samples of porcine thoracic aortas immersed in a hyperosmotic solution. The tissue deformations were tracked using optical coherence tomography (OCT) during the tensile tests and digital volume correlation (DVC) was used to obtain measurements of depth-resolved strains across the whole thickness of the tested aortas. The hyperosmotic solution exacerbated chemoelastic effects, and we were able to measure different manifestations of these chemoelastic effects: swelling of the media inducing a modification of its optical properties, existence of a transverse tensile strain. For the first time ever to our best knowledge, 3D strains induced by chemoelastic effects in soft tissues were quantified thanks to the OCT-DVC method. Without doubt, chemoelasticity plays an essential role in arterial mechanobiology in vivo and future work should focus on characterizing chemoelastic effects in arterial walls under physiological and disease conditions. Statement of significance: Chemoelasticity, coupling osmotic phenomena and mechanical stresses, is essential in soft tissue mechanobiology. For the first time ever, we measure and analyze 3D strain fields induced by these chemoelastic effects thanks to the unique combination of OCT imaging and digital volume correlation.