Antibiotic-Coated ePTFE Decreases Graft Colonization and Neointimal Hyperplasia

Susceptibility of ePTFE vascular grafts and bioengineered human acellular vessels to infection

“…7 Sustained infection of ePTFE grafts not only increases a patient's risk of bacteremia and sepsis but has also been shown to increase the risk of intimal hyperplasia and graft failure because of stenosis even at subclinical levels of bacterial contamination. 24,25 When infected, ePTFE vascular grafts usually do not recover and thus require surgical intervention to remove the infected and often biofilm-covered ePTFE material. 5,26 It has been suggested that as many as 35% of all synthetic arteriovenous grafts are eventually abandoned due to infection.…”

“…Specifically, the interstitial porosity, surface tension, and electronegativity of synthetic vascular graft materials have previously been shown to attract and support bacterial adherence. 27,28 The ability of bacteria within contaminated ePTFE to persist without adequate clearance by host immune cells, resist antibiotic therapy, and produce sustained infections and biofilms 14,25,29 may be connected to k i r k t o n e t a l h u m a n a c e l l u l a r v e s s e l s r e s i s t i n f e c t i o n i n a p r e c l i n i c a l m o d e l interstitial colonization and subsequent inaccessibility of bacteria within the ePTFE matrix. Interstitial bacterial accumulation within the ePTFE matrix has previously been shown in vitro 30 as well as in vivo here in our study and by others.…”

“…Interstitial bacterial accumulation within the ePTFE matrix has previously been shown in vitro 30 as well as in vivo here in our study and by others. 7,25,31 Shell et al 7 demonstrated that the interstitial matrix of ePTFE grafts provided a favorable environment for bacteria, including S. aureus, to survive and proliferate for up to 6 wk (study end-point) in a porcine iliac interposition graft model. 7 Bacteria residing within contaminated ePTFE in vivo likely further evade host immune defenses because ePTFE has been shown to disrupt the chemo-stimulated migratory capabilities of neutrophils, 8 leading to poor infiltration of neutrophils into ePTFE.…”

Autologous Vascularization: A Method to Enhance the Antibacterial Adhesion Properties of ePTFE

“…In recent years, many attempts have been made to modify bioimplant materials to enhance their biocompatibility and antibacterial activity and to minimize adverse foreign-body reactions, particularly the antibiotic/immunologic coatings of prospective devices for clinical application. 7,8 In tissue engineering, graft survival can be achieved by construction of a parenchyma or blood vessel network on the surface of a scaffold material. 9 An 2-N,6-O-sulfated chitosan (26SCS)coated hierarchical scaffold composed of poly(lactic-co-glycolic acid) (PLGA) microspheres scaffold surface loaded with vascular endothelial growth factor can promote angiogenesis and increase the external blood supply of the material to a certain extent.…”

The in vitro research of bacterial invasion of prosthetic vascular grafts: comparison of elastomer-sealed and gelatin-coated Dacron vascular grafts

“…Thus, the factors involved in the infectivity of prosthetic vascular grafts should be established in relation to bacterial adherence [1] and invasion. Regarding bacterial adherence to vascular grafts [1] and antibiotic-coated grafts [2, 3], some in vitro and in vivo [4] studies have been published. We investigated bacterial invasion from the outer surface to the inside of vascular grafts using a new experimental system in vitro to consider the relationships between the time required for invasion and the amount of bacteria inside the grafts.…”