Experimental study on the pulse wave propagation in viscoelastic vessel tubes

The pressure wave in arteries shows similar characteristic of pulse wave. Therefore, in order to investigate the pulse wave behavior due to properties of tube and blood, the experimental study was performed using artificial polymer tube and viscous liquid. The polyurethane tube and glycerin solution were used as simulated of blood vessels and simulant blood, respectively. In case of glycerin solution 40 wt.% which corresponds to ordinary blood viscosity, the attenuation coefficient of a pressure wave decreased from 4.3 to 1.6 dB/m due to the tube stiffness (Young's modulus: 60 - 200 kPa). When the viscosity of liquid increases from approximately 4 - 10 mPa . s (the range of human blood viscosity) in the stiff tube, the attenuation coefficient of a pressure wave changed from 1.6 to 3.2 dB/m. The hardening of the blood vessel by aging or the illness and the increase of blood viscosity possibly have opposite influence to intravascular pressure wave.