Cardiovascular diseases remain the leading cause of death globally. Synthetic vascular grafts are among the crucial components in vascular reconstruction surgeries, but they have demonstrated low patency rates when replacing small-diameter vessels.
Thrombogenesis remains the primary failure of synthetic vascular grafts. Endothelial coverage is crucial to provide an antithrombogenic surface. However, most synthetic materials do not support cell adhesion, and transanastomotic endothelial migration is limited.
Using a natural material derived from seaweed, scientists from the University of Waterloo have promoted vascular cell growth, prevented blood clots, and improved synthetic vascular graft performance. This approach is essential in small artificial blood vessels, prone to clots that can develop into full blockages.
Dr. Evelyn Yim, a chemical engineering professor and University Research Chair who leads the project, said, “There is a crucial need to develop synthetic vascular graft materials that will increase the rate of long-term functions.”
Scientists added fucoidan, made from seaweed, to modify synthetic blood vessels. Fucoidan has a structure similar to heparin, a drug used as an anticoagulant. Fucoidan encourages the proliferation of vascular cells surrounding the inner surface of the graft when used with a nanotechnology process called micropatterning, dramatically lowering the likelihood of clot formation.
Patients may benefit from fewer problems, a higher quality of life, and a lower likelihood of recurring blockages necessitating further medication or surgery.
Yim said, “A functional, off-the-shelf, small-diameter vascular graft will help save lives. What’s important is that they will be much longer-lasting and allow blood to flow freely.”
This new technique has successfully been tested using fucoidan and micropatterning on small animals. Scientists are planning to expand to large animal testing before advancing to clinical trials.
Journal Reference:
- Yuan Yao et al. Fucoidan and topography modification improved in situ endothelialization on acellular synthetic vascular grafts. Bioactive Materials. DOI: 10.1016/j.bioactmat.2022.10.011