title: Long-term animal implantation study of biotube-autologous small-caliber vascular graft fabricated by in-body tissue architecture.
abstract: A mold for the preparation of an in-body tissue architecture-induced autologous vascular graft, termed "biotube," was prepared by covering a main silicone rod (outer diameter, 3 mm; length, 30 mm) with two pieces of polyurethane sponge tubes (internal diameter, 3 mm; length, 3 mm) at both ends. The molds were embedded into the dorsal subcutaneous pouch of rabbits (weighing ca. 2 kg) for 2 months. After harvesting the rods with the formed surrounding tissues, the rods were removed to create biotubes impregnated with anastomotic reinforcement cuffs at both ends. The biotubes had homogeneous, thin connective tissue wall (thickness, 76 ± 37 μm) that was primarily composed of collagen and fibroblasts. One biotube was loaded with argatroban and autoimplanted in the carotid artery for 26 months. Neither antiplatelet nor anticoagulant agents were administered, except for an intraoperative heparin injection. Follow-up angiography showed no aneurysm formation, rupturing, or stenosis during implantation. At the end of implantation, the wall thickness of biotube (212 ± 24 μm at the anastomosis portion and 150 ± 14 μm at the midportion) was similar to that of native artery (189 ± 23 μm). The luminal surface was completely covered with endothelial cells on the formed lamina elastica interna-like layer. The regenerated vascular walls comprised multilayered smooth muscle cells and dense collagen fibers with regular circumferential orientation. A remarkable multilayered elastin fiber network was observed near the anastomosis portion. Biotubes could thus be used as small-caliber vascular prostheses that greatly facilitate the healing process and exhibit excellent biocompatibility.
authors.affiliation: Division of Medical Engineering and Materials, National Cerebral and Cardiovascular Center Research Institute, Suita, Osaka 565-8565, Japan.
authors.forename: Taiji
authors.initials: T
authors.lastname: Watanabe
authors.forename: Keiichi
authors.initials: K
authors.lastname: Kanda
authors.forename: Masashi
authors.initials: M
authors.lastname: Yamanami
authors.forename: Hatsue
authors.initials: H
authors.lastname: Ishibashi-Ueda
authors.forename: Hitoshi
authors.initials: H
authors.lastname: Yaku
authors.forename: Yasuhide
authors.initials: Y
authors.lastname: Nakayama
mesh_terms: D000818:Animals; D000991:Antithrombins / Q000494:pharmacology; D001120:Arginine / Q000031:analogs & derivatives; D001705:Bioprosthesis; D001807:Blood Vessel Prosthesis; D019917:Blood Vessel Prosthesis Implantation / Q000379:methods; D002339:Carotid Arteries / Q000601:surgery; D010875:Pipecolic Acids / Q000494:pharmacology; D011817:Rabbits; D012828:Silicones / Q000737:chemistry*; D015607:Stents; D013449:Sulfonamides
chemical_list: D000991:Antithrombins; D010875:Pipecolic Acids; D012828:Silicones; D013449:Sulfonamides; D001120:Arginine; C031942:argatroban