Mechanical properties of 3D-printed blood vessels

Abstract

The demand for vascular substitutes in clinical practice has

increased, and 3D-printed blood vessels could be advantageous

alternatives. Determining the mechanical properties of 3D-printed

blood vessels is important to further improve the technology and

clinical application. Here, dogbones with and without cells were

generated by 3D printing with combined UV curing and hydrogel

ion curing. Tensile tests were performed to measure the mechani

cal parameters of the dogbones and build two kinds of fluid–solid

interaction models. In accordance with hydrodynamics and mo

mentum theorems, the velocities in accelerated ejection period,

ejection peak, reduced ejection period, and early diastolic period

were selected as inlet velocities. Velocity distribution on the sym

metry surface of the fluid and the stress and strain of the solid

tube under different velocities were analyzed. Results reveal that

the velocity decreases gradually from the fluid center to the wall.

At a high inlet velocity, the fluid velocity is high, while the stress

and strain of the wall increase. During cardiac ejection peak, the

stress on the wall reaches the maximum value of 2018 Pa, which

is much lower than the ultimate stress. In addition, the strength

and stiffness decrease for the vessels added with cells. This work

provides a feasible method for measuring the mechanical proper

ties of 3D-printed blood vessels.