The influence of the opening angle on the stress distribution through the saphenous vein wall

Abstract

In the present study, the inflation test of human vena saphena magna was conducted to obtain data suitable for multi-axial constitutive modeling at overloading conditions (pressures up to approximately 18 kPa). Subsequently the data were fitted with a hyperelastic, nonlinear and anisotropic constitutive model based on the theory of the closed thickwalled tube. It was observed that initial highly deformable behavior in the pressure–circumferential stretch response is followed by progressive large strain stiffening, which is in contrast to the pressure–axial stretch response. The effect of possible residual stress was evaluated in a simulation of the intramural stress distribution with the opening angle prescribed to 0°, 10°, 20°, 30°, 40°, and 50°. The result suggests that the optimal opening angle making the stress distribution through the wall thickness uniform is about 20°.