Tissue-engineered blood vessel mimics in complex geometries for intravascular device testing

Area of Science:

• Biomedical Engineering
• Tissue Engineering
• Cardiovascular Research

Background:

• Intravascular stents are vital for treating coronary heart disease by promoting re-endothelialization, a key indicator of stent success.
• Current in vitro blood vessel mimics (BVMs) lack the complex geometries of native coronary arteries, limiting their preclinical testing utility.
• Regulatory bodies recommend testing devices in bent and bifurcated vessels to better reflect in vivo conditions.

Purpose of the Study:

• To develop and characterize blood vessel mimics (BVMs) in complex, non-straight geometries.
• To create bioreactors capable of cultivating BVMs in bent and bifurcated configurations.
• To assess the feasibility of using these complex BVMs for preclinical stent evaluation.

Main Methods:

• Designed and constructed novel bioreactors to accommodate scaffolds in bent (>45°) and bifurcated shapes.
• Cultured human umbilical vein endothelial cells onto complex-shaped scaffolds to create BVMs.
• Characterized cell deposition and distribution within the complex BVMs.
• Performed a proof-of-concept stent deployment within a severely angulated BVM.

Main Results:

• The developed bioreactors successfully housed complex-geometry scaffolds.
• Endothelial cell deposition was uniform throughout the complex BVMs, with no significant differences in cell density.
• A coronary stent was successfully deployed in a severely angulated BVM, demonstrating model viability.

Conclusions:

• Bioreactors can be effectively constructed to house complex-shaped blood vessel mimics.
• Complex-geometry BVMs can be successfully developed with evenly dispersed endothelial cells, mimicking native coronary arteries.
• These advanced BVMs offer a promising platform for preclinical evaluation of coronary stents in realistic vascular geometries.