title: New prostheses for use in bypass grafts with special emphasis on polyurethanes.
abstract: Vascular bypass procedures using traditional prosthetic grafts such as polytetrafluoroethylen (PTFE) and polyethylene tetraphthlate (Dacron) are prone to failure when used in low flow states such as in below knee bypass and when the diameter of the graft is less than 6 mm. A major factor in this is compliance mismatch between the graft and the diseased vessel, which may cause intimal hyperplasia at the distal anastomosis. PTFE and Dacron are rigid grafts with poor compliance. By improving the compliance of the prosthetic graft it is hoped that patency will improve. Recent advances in polyurethane chemistry have developed materials that do not degrade and which allow compliance matching of the graft to the patient's vasculature. It is now possible to manufacture biologically and haemodynamically compatible grafts with small diameter from these polyurethane graft materials. This review will focus on the lack of compliance in current vascular bypass grafts and the promise of the new polyurethane polymers in a new generation of small-bore bypass grafts.
authors.affiliation: Tissue Engineering Centre, University Department of Surgery, The Royal Free Hospital and Royal Free & University College Medical School, University College London, Pond Street, NW3 2QG, London, UK.
authors.forename: Alok
authors.initials: A
authors.lastname: Tiwari
authors.forename: Henryk
authors.initials: H
authors.lastname: Salacinski
authors.forename: Alexander M
authors.initials: AM
authors.lastname: Seifalian
authors.forename: George
authors.initials: G
authors.lastname: Hamilton
mesh_terms: D001672:Biocompatible Materials / Q000627:therapeutic use*; D001807:Blood Vessel Prosthesis / Q000639:trends*; D019917:Blood Vessel Prosthesis Implantation; D004730:Endothelium, Vascular / Q000502:physiology; D005544:Forecasting; D006439:Hemodynamics / Q000502:physiology; D006801:Humans; D011093:Polyethylene Terephthalates / Q000009:adverse effects; D011138:Polytetrafluoroethylene / Q000009:adverse effects; D011140:Polyurethanes / Q000009:adverse effects / Q000627:therapeutic use*; D011474:Prosthesis Design; D011475:Prosthesis Failure; D023822:Tissue Engineering; D014652:Vascular Diseases / Q000601:surgery
chemical_list: D001672:Biocompatible Materials; D011093:Polyethylene Terephthalates; D011140:Polyurethanes; D011138:Polytetrafluoroethylene