Vascular grafts diameter

The worldwide market for vascular grafts was approximately 150 million and growing at about 5% annuaUy as of 1995. The vascular graft area has tremendous market potential in development of smaU-diameter grafts of 3—4 mm for coronary bypass surgery. The total market for the intra-aortic baUoon pump, a cardiac-assist device, is ca 80 million worldwide. About 75,000 patients were supported by these baUoon pumps in 1994. This market is thought to have peaked. 

Over half a million vascular graft replacements are performed yearly. Most of these grafts are made of PET and PTFE. These relatively large diameter grafts work when blood flow is rapid, but they generally fail for smaller vessels. 

Goissis, G., Suzigan, S., Parreira, D. R., Maniglia, J. V., Braile, D. M., and Raymundo, S. (2000). Preparation and characterization of collagen-elastin matrices from blood vessels intended as small diameter vascular grafts. Artif. Organs 24, 217-223. 

Wu H et al (2010) Electrospinning of small diameter 3-D nanofibrous tubular scaffolds with controllable nanofiber orientations for vascular grafts. J Mater Sci Mater Med 21(12) 3207-3215... 

The Importance of Vascular Graft Surface Composition as Demonstrated by a New Gas Discharge Treatment for Small Diameter Grafts... 

In this study, we describe the modification of PTFE by a chemical method in combination with a biochemical method leading to an improved cell adhesion. The modification was first developed with punched disks from PTEE film, and was then transferred to commercially available vascular grafts made of PTEE. The aim was to retain the mechanical properties of the polymer so that only the biological properties of the inner surface of the graft were changed. Thus it would become possible to couple adhesion proteins to the previously inert and hydrophobic polymer surface to favor adhesion and attachment of endothelial cells (ECs) withstanding shear stress as it occurs in small-diameter vascular grafts. 

Prechtel, E., Yoimg, K., Goldman, S. et al.. Design, synthesis, and mechanical characterization of a resorbable composite small diameter vascular graft as a tissue engineered construct, Trans. Soc. Biomater., 28, 200, 2002. 

In Brown s subsequent work [50], the potential of synthesizing new nanocomposites from NCC and fibrin for small-diameter replacement vascular graft [SDRVG] application was demonstrated Fig. 3.4. 

G. Soldani, P. Losi, M. Bernabei, S. Burchielli, D. Chiappino, S. Kull, E. Briganti, D. Spiller, Long term performance of small-diameter vascular grafts made of a poly(ether)urethane-polydimethylsiloxane semi-interpenetrating polymeric network. Biomaterials 31 (9) (2010) 2592-2605. 

H. Bergmeister, C. Grasl, I. Walter, R. Plasenzotti, M. Stoiber, C. Schreiber, U. Losert, G. Weigel, H. Schima, Electrospun small-diameter polyurethane vascular grafts ingrowth and differentiation of vascular-specific host cells, Art. Organs 36 (1) (2012) 54-61. 

Expanded poly(tetrafluoro ethylene) (ePTFE) CORE-TEX W.L. Core Associates, Flagstaff, USA Regenerative membrane, osteoconductive membrane, large diameter aortic, and carotid vascular grafts, tension-free repair of ventral incisional hernia orbital reconstruction, facial reconstruction, rhinoplasty... 

Fig. 10.7 Examples of biomedical applications of BC are meniscus replacements (pig meniscus on the left, BC meniscus on the right), artificial blood vessels and wound dressing for skin heaiing [76-78], Nanocellulose (bacterial cellulose, BC), such as that produced by Acetobacter xylinum, has shown promising results as a replacement material for small diameter vascular grafts (Fig. 10.8). These BC tubes have been tested in a pig model as an infrarcnal aortic bypass and show promising results for use as vascular grafts in the future...

Vascular grafts are used in surgery to replace damaged thick arteries or veins 6 mm, 8 mm, or 1 cm in diameter. Commercially available vascular grafts are produced from polyester (e.g. Dacron) or PTFE (e.g. Teflon) with either woven or knitted structures... 

M D Phaneuf, P JBrown, M J Bide, F W LoGerfo, Nanotechnology in cardiovascular devices Development of a novel small-diameter vascular graft . Proceedings, Biointerface 2004. 

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