In vivo measurements of change in viscoelasticity of arterial wall during the flow-mediated dilation

Hiroshi Kanai, Hideyuki Hasegawa, Kazuki Ikeshita

Research output: Chapter in Book/Report/Conference proceedingConference contribution

Abstract

The present paper introduces in vivo measurements of viscoelasticity of arterial wall developed in our laboratory. The endothelial dysfunction is considered to be an earliest stage of atherosclerosis. Moreover, it was reported that the smooth muscle, which constructs the media of the artery, changes its characteristics due to atherosclerosis. Therefore, it is essential to develop an in vivo measurement method to assess the regional endothelial function and mechanical property (viscoelasticity) of the arterial wall. To evaluate the endothelial function, there is a conventional technique for measuring the transient change in the diameter of the brachial artery caused by flow mediated dilation (FMD) after the release of avascularization. However, this method does not directly evaluate the viscoelasticity of the intima-media region of the arterial wall. In the present paper, therefore, we proposed a method for simultaneous measurement of waveforms of the radial strain and blood pressure at the radial artery, and we developed its measurement system. From in vivo experiments, the viscoelasticity parameters of the arterial wall were estimated from the measured stress-strain relationship (hysteresis loop) using the least-square method and their transient changes after the release of avascularization were revealed. For healthy young persons, the slope of the hysteresis loop decreased due to the FMD, which corresponds to decrease in the elastic modulus. At the same time, the area of the loop increased after recirculation, which corresponds to the increase of the ratio of the loss modulus (viscosity) to the elastic modulus when the Voigt model is assumed. These results show a potential of the proposed method for thorough analysis of the transient change in viscoelasticity due to FMD.

Original languageEnglish
Title of host publicationProceedings of the ASME International Mechanical Engineering Congress and Exposition 2009, IMECE 2009
PublisherAmerican Society of Mechanical Engineers (ASME)
Pages515-521
Number of pages7
ISBN (Print)9780791843758
DOIs
Publication statusPublished - 2010 Jan 1
Event2009 ASME International Mechanical Engineering Congress and Exposition, IMECE2009 - Lake Buena Vista, FL, United States
Duration: 2009 Nov 132009 Nov 19

Publication series

NameASME International Mechanical Engineering Congress and Exposition, Proceedings
Volume2

Other

Other2009 ASME International Mechanical Engineering Congress and Exposition, IMECE2009
CountryUnited States
CityLake Buena Vista, FL
Period09/11/1309/11/19

ASJC Scopus subject areas

  • Mechanical Engineering

Fingerprint Dive into the research topics of 'In vivo measurements of change in viscoelasticity of arterial wall during the flow-mediated dilation'. Together they form a unique fingerprint.

Cite this