Study of the frecuency dependence of Young’s modulus in synthetic and biological ducts.

Abstract

The study of frequency dependence of Young’s modulus allows to describe mechanically arterial ducts. This modulus is complex, whose real component represents the purely elastic properties of the material, while its imaginary component represents purely viscous properties. In this work, the complex elastic modulus in two types of ducts was experimentally determined: synthetic type and biological type, (bovine artery). For this purpose, a continuous circulation biodynamic simulator (Bose® Corporation ElectroForce Systems Group) was used where the ducts were subjected to sinusoidal variations of internal pressure, frequency between 1 and 5 Hz. It was observed that the ratio between the measured pressure (Statham P23 DB transducer, Statham‐Gould, Valley View) and the acquired diameter (Laser transducer, Mitutoyo Corporation) constituted a Lissajous figure, with a representative slope of elastic behavior and a hysteresis indicative of viscosity parietal. Given the increase in frequency, the loop experienced an increase in hysteresis. For the calibrated tube, the elasticity (given by the storage modulus) resulted in the order of 14.1 mmHg/mm, while for the other it was 62.3 mmHg/mm. In the case of the bovine duct, the value was 4.88 mmHg/mm. On the other hand, the evaluation of the storage modulus showed differentiated results. While the elastic ducts manifested a linear increase with frequency, the arterial showed a logarithmic dependence. By virtue of them, the synthetic duct could be represented modelling viscosity as a linear function of frequency, but it is not the case of the arterial duct, whose viscoelastic behavior is nonlinear.Support or Funding Information [1]RICARDO L. ARMENTANO y E.I. CABRERA FISCHER, Biomecánica Arterial: Fundamentos para su abordaje en la clínica médica, primera edición, Librería AKADIA, Buenos Aires, 1994. [2]RICARDO L. ARMENTANO, DANIELA VALDEZ JASSO, LEANDO J. CYMBERKNOP, FLORENCIA MONTINI BALLARIN, DANIELA VELEZ, PABLO C. CARACCIOLO y GUSTAVO ABRAHAM, High Pressure Assenssment of Bilayered Electrospun Vascular Grafts by Means of an Electroforce Biodynamic System®, IEEE, 978‐1‐4244‐9270‐1, 3533‐3536, 2015. [3]D. A. MCDONALD, Blood Flow in Arteries, segunda edición, Edward Arnols, London, 1974. [4]W. K. MILNOR, Hemodynamics,Baltimore, MD, USA: WILLIAMS Y WILKINS, 1982. [5]B. S. GOW, M. G. TAYLOR, Measurements of viscoelastic properties of arteries in the living dog, Circ Res 23 (1): 111‐122, 1968. [6]P.B. DOBRIN, Mechanical properties of arteries., Physiol Rev 58 (2): 397‐460, 1978. [7]Y. C. FUNG, Biomechanics. Mechanical Properties of living tissues, Springer‐Verlag, New York, 1981. [8]DANIEL BIA, ISMAEL AGUIRRE, YANINA ZÓCALO, LUCÍA DEVERA, EDMUNDO CABRERA FISCHERC, Y RICARDO ARMENTANO. Diferencias regionales en viscosidad, elasticidad y amortiguamiento parietal de arterias sistémicas: análisis isopulsátil de la relación presión‐diámetro arterial. [9]BERGEL DH. The dynamic elastic properties of the arterial wall. J Physiol 156: 458‐ 469, 1961b.