PLCL-TPU bi-layered artificial blood vessel with compliance matching to host vessel

Abstract

Compliance mismatch between the artificial blood vessel and the host vessel leads to abnormal hemodynamics and is a major mechanical trigger of intimal hyperplasia. Efforts have been made to achieve higher compliance of artificial blood vessels. However, the preparation of artificial blood vessels with compliance matching to host vessels has not been realized. A bi-layered artificial blood vessel was successfully prepared by dip-coating and electrospinning composite method using poly(L-Lactide-co-caprolactone) (PLCL) and thermoplastic poly(ether urethane) (TPU). In the case of a certain wall thickness (200 μm), thickness ratios of the PLCL inner layer (dip-coating method) and TPU outer layer (electrospinning method) were controlled at 0:1, 1:9, 3:7, 5:5, 7:3, and 1:0 respectively and the compliance, radial tensile properties, burst pressure, and suture retention strength were investigated. Results showed compliance value of the artificial blood vessel decreased with the increase of the thickness ratio, which suggested the compliance of the bi-layered artificial blood vessel can be regulated by adjusting the ratio of the inner and outer layer thicknesses. In the six different artificial blood vessels, the one with thickness ratio of 1:9 not only had high compliance (8.768 ± 0.393%/100 mmHg) but also can guarantee the other mechanical properties, such as the radial breaking strength (6.333 ± 0.689 N/mm), burst pressure (534.473 ± 20.899 mmHg), and suture retention strength (300.773 ± 9.351 cN). The proposed artificial blood vessel preparation method is expected to achieve compliance matching with the host vessel. It is beneficial for eliminating abnormal hemodynamics and reducing intimal hyperplasia.

The Effect of Plasma Treatment on the Mechanical and Biological Properties of Polyurethane Artificial Blood Vessel

“…Among them, autologous blood vessels are a better choice as vascular grafts, because of their good autologous histocompatibility [10]. However, due to the fact that vascular grafts need to meet a series of conditions, such as inner diameter, length, etc., there are few autologous blood vessels that meet the requirements; artificial blood vessels have attracted much attention in the medical field in recent years due to their good designability [11][12][13][14][15][16][17][18].…”