Anisotropic in vitro vessel model using poly(vinyl alcohol) hydro gel and mesh material

In the present study, the authors fabricated straight multilayer hybrid tubular in vitro vessel models (inner diameter D_in 10 mm; thickness T = 4 mm) composed of poly(vinyl alcohol) hydrogel (PVA-H) and anisotropic mesh materials. The authors performed tensile, stress-relaxation and cyclic-tensile tests using axial and circumferential test pieces as well as pressure-diameter (P-D) tests using tubular test piece. In the tensile and stressrelaxation tests, the anisotropic and nonlinear mechanical properties and hysteresis characteristic of the in vitro models were confirmed. The in vitro models also showed behavior qualitatively similar to that of native arteries in cycle-tensile and P-D tests. These results demonstrate that the mechanical properties of native vessels can be duplicated in an in vitro model by controlling the components of the mesh material, the orientation of elastic fibers in the mesh material, and the concentration and thickness of PVA-H layers.