Date of Award
Summer 2023
Document Type
Thesis - Restricted
Degree Name
Master of Science (MS)
Department
Biomedical Engineering
First Advisor
Wang, Bo
Second Advisor
Tefft, Brandon
Third Advisor
Garcia, Guilherme
Abstract
Heart bypass surgery has become a common therapeutic strategy to save heart attack patients from death. However, there are issues with the availability of graft resources for patients who cannot use autologous vessels due to their health conditions. To solve this problem, this study aims to develop a small-diameter vascular graft based on the human decellularized amniotic membrane (DAM) as an alternative to autologous vessels. The human amniotic membrane was harvested from the placenta, obtained from consenting and de-identified donors, and decellularized to remove cellular components while preserving its extracellular matrix. Small-diameter vascular grafts were fabricated using the DAM as a scaffold (DAM-based vascular graft) and implanted in Sprague-Dawley rats' abdominal aorta; these rats were monitored for up to 16 months. Another small-diameter vascular graft was implanted into the porcine common carotid artery. The animals were monitored for 1-month post-surgery. Transplantation outcomes were assessed through various methods to evaluate graft patency, biocompatibility, and hemodynamic performance. Results showed that the DAM-based vascular graft remained patent in rats during observation, and histological analysis confirmed tissue remodeling. However, thrombosis was detected in porcine 1-week post-implantation. Additionally, long-term patency was maintained with no signs of stenosis or thrombosis, and hemodynamic assessment showed physiological blood flow patterns and stable blood flow velocity in rat model. These results demonstrate favorable transplantation outcomes in a long-term evaluation of the rat model. However, more big animal tests must be achieved to prove that using the human amniotic membrane as a scaffold has potential advantages for vascular treatment.