Biaxial mechanical properties of intact and layer-dissected human carotid arteries at physiological and supraphysiological loadings
2010 (English)In: American Journal of Physiology. Heart and Circulatory Physiology, ISSN 0363-6135, E-ISSN 1522-1539, Vol. 298, no 3, H898-H912 p.Article in journal (Refereed) Published
Sommer G, Regitnig P, Koltringer L, Holzapfel GA. Biaxial mechanical properties of intact and layer-dissected human carotid arteries at physiological and supraphysiological loadings. Am J Physiol Heart Circ Physiol 298: H898-H912, 2010. First published December 24, 2009; doi:10.1152/ajpheart.00378.2009.-Specimens of intact wall tubes of human common carotid arteries (CCA), internal carotid arteries (ICA) (n = 11, age 77.6 yr, SD 6.3), and related adventitia and media-intima tubes are mechanically examined. Cyclic, quasi-static extension-inflation tests at different axial stretches are performed on preconditioned tube specimens. Stress-free configurations show significant stress releases in the circumferential direction of the intact CCA and ICA walls and in the axial directions of the intact CCA walls and the CCA and ICA adventitias. All investigated tissues exhibit strong nonlinear, pseudoelastic mechanical behavior with small hysteresis. The "inversion" feature, where the pressure/axial stretch relationship becomes a vertical line, is found only for intact walls. Axial "inversion stretches" are 1.15 (SD 0.06) for CCA and 1.14 (SD 0.06) for ICA, and related external axial forces are 0.43 N (SD 0.15) and 0.30 N (SD 0.22), respectively. Significant negative correlations between age and axial inversion stretches for CCA (r = -0.67, P = 0.03) and ICA (r = -0.29, P = 0.04) are identified. Adventitias are very compliant at low pressures, but change into stiff tubes at high pressures. The burst pressure of the adventitia is beyond 250 kPa. A relatively low burst pressure of similar to 60 kPa is found in the media-intima tubes, in which the pressure/circumferential stretch relationships are almost independent of the axial stretches. Stress analyses indicate a high degree of material anisotropy for all investigated tissues. High circumferential and axial stresses occur in the media-intima tubes at physiological conditions. The obtained data are intended to serve for an improvement of constitutive laws, determination of constitutive parameters, and enhancing our knowledge of the mechanical functions of arteries and their associated layers in specific pathophysiological and clinical problems, such as hypertension and angioplasty with stenting.
Place, publisher, year, edition, pages
2010. Vol. 298, no 3, H898-H912 p.
arterial wall mechanics, human carotid artery, biaxial testing, residual stress, biomechanics, elastic properties, in-vitro, residual-stress, adventitia, media, bifurcation, pressure, behavior, tissue, model
Medical Laboratory and Measurements Technologies Applied Mechanics
IdentifiersURN: urn:nbn:se:kth:diva-19253DOI: 10.1152/ajpheart.00378.2009ISI: 000274931500020ScopusID: 2-s2.0-77749279489OAI: oai:DiVA.org:kth-19253DiVA: diva2:337300
QC 201005252010-08-052010-08-052011-01-21Bibliographically approved