HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text Full Text (PDF) All Versions of this Article: 288/6/H2581    most recent 00648.2004v1 Alert me when this article is cited Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in Web of Science Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Web of Science (6) Citing Articles via Google Scholar Google Scholar Articles by Pandit, A. Articles by Kassab, G. S. Search for Related Content PubMed PubMed Citation Articles by Pandit, A. Articles by Kassab, G. S.

Biaxial elastic material properties of porcine coronary media and adventitia

Department of Biomedical Engineering, University of California, Irvine, California

Submitted 29 June 2004 ; accepted in final form 8 January 2005

The importance of mechanical stresses and strains has become well recognized in vascular physiology and pathology. To compute the stress and strain on the various components of the vessel wall, we must know the constitutive equations for the different layers of the vessel wall. The objective of the present study is to determine the constitutive equation of the coronary artery treated as a two-layer composite: intima-media and adventitial layers. Twelve hearts were obtained from a local slaughterhouse, and the right coronary artery and left anterior descending artery were dissected free from the myocardium. The vessel wall was initially mechanically tested biaxially (inflation and axial extension) as a whole (intact wall) and subsequently as intima-media or adventitial layer. A Fung-type exponential strain energy function was used to curve fit the experimental data for the intact wall and individual layers for the right coronary artery and left anterior descending artery. Two methods were used for the determination of material constants, including the Marquardt-Levenberg nonlinear least squares method and the genetic algorithm method. Our results show that there were no statistically significant differences in the material constants obtained from the two methods and that either set of elastic constants results in good fit of the data. Furthermore, at an in vivo value of axial stretch ratio, we find that the stiffness is as follows: intima-media > intact > adventitia. These results underscore the composite nature of coronary arteries with different material properties in each layer. The present results are necessary for analysis of coronary artery mechanics and to provide a fundamental understanding of vessel physiology.

stress; strain; constitutive equation; material constants; two-layer model

This article has been cited by other articles:

				G. P. Kwon, J. L. Schroeder, M. J. Amar, A. T. Remaley, and R. S. Balaban Contribution of Macromolecular Structure to the Retention of Low-Density Lipoprotein at Arterial Branch Points Circulation, June 3, 2008; 117(22): 2919 - 2927. [Abstract] [Full Text] [PDF]

				G. S Kassab Biomechanics of the cardiovascular system: the aorta as an illustratory example J R Soc Interface, December 22, 2006; 3(11): 719 - 740. [Abstract] [Full Text] [PDF]

				C. Wang, M. Garcia, X. Lu, Y. Lanir, and G. S. Kassab Three-dimensional mechanical properties of porcine coronary arteries: a validated two-layer model Am J Physiol Heart Circ Physiol, September 1, 2006; 291(3): H1200 - H1209. [Abstract] [Full Text] [PDF]