scholarly journals Electrospun poly-ε-caprolactone scaffold modified with catalytic nitric oxide generation and heparin for small-diameter vascular graft

RSC Advances ◽  
2017 ◽  
Vol 7 (30) ◽  
pp. 18775-18784 ◽  
Author(s):  
Jingchen Gao ◽  
Yaping Wang ◽  
Siyuan Chen ◽  
Di Tang ◽  
Li Jiang ◽  
...  

Vascular grafts are significantly needed in peripheral vascular surgery; however, small diameter grafts are not always available, and synthetic grafts perform poorly because of acute thrombosis and neointimal proliferation after implantation.

1987 ◽  
Vol 154 (5) ◽  
pp. 533-537 ◽  
Author(s):  
Philip N. Sawyer ◽  
Joseph Fitzgerald ◽  
Martin J. Kaplitt ◽  
Richard J. Sanders ◽  
George M. Williams ◽  
...  

2003 ◽  
Vol 90 (12) ◽  
pp. 1128-1134 ◽  
Author(s):  
Claire Esposito ◽  
Wanda Popescu ◽  
Henry Rinder ◽  
Jeffrey Schwartz ◽  
Brian Smith ◽  
...  

SummaryGraft occlusion following peripheral vascular surgery is attributable to some combination of acute thrombosis, and progression of atherosclerosis: interactions between leukocytes and activated platelets may play a role in both of these processes. This investigation measured perioperative leukocyte-platelet conjugate formation, and leukocyte and platelet activation in 46 patients undergoing surgery for lower extremity peripheral vascular disease (PVD). All patients were followed for graft patency over the next 6 months; 27 patients had grafts that remained patent while 19 had graft occlusion. On postoperative day #1 (POD#1), the graft occlusion group demonstrated a significantly greater increase in circulating levels of both mono-cyteplatelet and neutrophil (PMN)-platelet conjugates compared to the patent graft patients (p=0.015 and 0.018, respectively). PMN activation, assessed by increases in surface CD11b expression, was also significantly increased on POD#1 in the graft occlusion group compared to the patent group (p=0.026). The percentage of circulating activated (CD62P+) platelets did not differ between groups, but patients with graft occlusion demonstrated a higher percentage of younger, reticulated platelets throughout the study period (p=0.008), indicating increased platelet turnover.We conclude that in the early postoperative period, leukocyte-platelet adhesion, PMN activation, and platelet turnover are significantly greater in PVD patients who go on to develop later graft occlusion. Cellular activation and heterotypic cell interactions in peripheral vascular surgery patients may be important in the etiologies of thrombosis and/or accelerated atherosclerosis leading to graft loss.


2020 ◽  
pp. 039139882098002
Author(s):  
Zhu Tong ◽  
Zeqin Xu ◽  
Yisha Tong ◽  
Lixing Qi ◽  
Lianrui Guo ◽  
...  

Background: Application of tissue engineered vascular grafts for small-diameter artery reconstruction has been a much anticipated advance in vascular surgery. The aim of this study is to assess the effectiveness of small-diameter decellularized vascular grafts in below-knee bypass surgery for diabetic lower extremity ischemia. Methods: Three patients with diabetic lower limb ischemia were admitted to the Department of Vascular Surgery, Xuanwu Hospital, Capital Medical University between May, 2010 and June, 2010. Decellularized porcine arteries with modified surface were implanted in the lower extremity for below-knee arterial revascularization. Imaging examination was performed for assessment of graft mechanical stability and patency at 1 month and 6 months after implantation. Results: At 6 months after implantation, all three grafts were patent with no stenosis or aneurysm formation of the grafts were found on imaging assessment with primary patency rate of 100% (3/3) both at 1 month and 6 months after graft insertion. Conclusion: Decellularized vascular graft with surface modification for the small-diameter artery reconstruction had good clinical results after 6 months follow-up in three patients with diabetic lower limb ischemia.


Author(s):  
Wei He ◽  
Alejandro Nieponice ◽  
Lorenzo Soletti ◽  
Yi Hong ◽  
Burhan Gharaibeh ◽  
...  

Although autologous vessel grafts are the gold standard for bypass procedures, they are limited by availability in many cases. Current synthetic grafts are not suitable for small-diameter (ID<6mm) vascular applications due to acute thrombosis. While a tissue-engineered vascular graft (TEVG), constructed by incorporating cells within a biodegradable scaffold, seems to be a possible solution to the challenge, its success greatly relies on an appropriate cell source and an efficient cellular delivery and carrier system. Terminally-differentiated vascular cells have poor self-renewal and expansion capabilities, exhibit phenotype switching in culture, and are difficult to harvest in necessary numbers, all of which represent limitations of their use in tissue engineering. Human adult mesenchymal stem cells (MSCs) exhibit multipotentiality and self-renewal capabilities, are more readily available, and therefore could overcome these limitations [1]. Pericytes closely encircle endothelial cells in capillaries. It has been shown that pericytes purified from multiple tissue types displayed multipotentiality, suggesting that they are developmental precursors of MSC [2].


Polymers ◽  
2019 ◽  
Vol 11 (5) ◽  
pp. 810 ◽  
Author(s):  
Guoping Guan ◽  
Chenglong Yu ◽  
Meiyi Xing ◽  
Yufen Wu ◽  
Xingyou Hu ◽  
...  

Acute thrombosis remains the main limitation of small-diameter vascular grafts (inner diameter <6 mm) for bridging and bypassing of small arteries defects and occlusion. The use of hydrogel tubes represents a promising strategy. However, their low mechanical strength and high swelling tendency may limit their further application. In the present study, a hydrogel vascular graft of Ca alginate/polyacrylamide reinforced with a braided fiber strut was designed and fabricated with the assistance of a customized casting mold. Morphology, structure, swellability, mechanical properties, cyto- and hemocompatibility of the reinforced graft were characterized. The results showed that the reinforced graft was transparent and robust, with a smooth surface. Scanning electron microscopic examination confirmed a uniform porous structure throughout the hydrogel. The swelling of the reinforced grafts could be controlled to 100%, obtaining clinically satisfactory mechanical properties. In particular, the dynamic circumferential compliance reached (1.7 ± 0.1)%/100 mmHg for 50–90 mmHg, a value significantly higher than that of expanded polytetrafluoroethylene (ePTFE) vascular grafts. Biological tests revealed that the reinforced graft was non-cytotoxic and had a low hemolysis percentage (HP) corresponding to (0.9 ± 0.2)%. In summary, the braided fiber-reinforced hydrogel vascular grafts demonstrated both physical and biological superiority, suggesting their suitability for vascular grafts.


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