University of Strathclyde website
Digital Collections - University of Strathclyde Library
Search Results Previous Searches E-Shelf
Login End Session
Guest
Search 'System Number= 000002796' in 'General Silo' Collection [ Sorted by: Name/Title ] Refine search
Table view Full view
Record 1 of 1 1
Add to E-Shelf
e-item icon
Link(s)
PDF of thesis T7473 PDF of thesis T7473 - (29 M)
Title Towards a tri-leaflet polyurethane heart valve prothesis / Tom G. Mackay.
Name Mackay, Tom G. .
Abstract Given the poor durability of bioprosthetic heart valves and thrombogenicity of mechanical valves, recent attention has been directed towards synthetic leaflet valves. The work of this thesis forms part of a project to develop a tri-leaflet polyurethane heart valve prosthesis. Two aspects have been addressed: in vitro valve function and durability test methods, and fabrication techniques for polyurethane valves. Existing in vitro valve testing facilities, comprising a hydrodynamic function tester (pulse duplicator) and accelerated fatigue testers, have been upgraded. An improved data acquisition system combined with a computerised control system has been developed for the pulse duplicator. The new system allows valve function to be more efficiently and reliably assessed, and also provides a means for characterising the pulse duplicator and its transducers. Accelerated fatigue testing facilities have been similarly enhanced by the introduction of a computerised data acquisition system. In order to exploit the design potential offered by the use of a synthetic material, an integrated CAD/CAM system has been developed for producing sculptured valve formers. Such formers have been incorporated into injection moulding tools for tri-leaflet polyurethane valves. Polyurethane valves have been moulded, but to date not with sufficiently thin leaflets: the required leaflet thickness (< 150 gm) results in a mould cavity which presents an enormous resistance to flow in the injection moulding process. However, a finite element-based mathematical model has been used to simulate the flow of molten polyurethane into the mould cavity and initial results suggest that it should indeed be possible to injection mould a polyurethane valve and a practicable means of achieving this has been identified. The sculptured formers incorporated into the injection moulding tools have also been used
Abstract to create dip moulded tri-leaflet polyurethane valves.
Abstract These dip moulded valves, though difficult to produce consistently, function reasonably well in the pulse duplicator and accelerated fatigue tests are in progress.
Publication date 1992
Name University of Strathclyde. Bioengineering Unit.
Thesis note Thesis PhD University of Strathclyde 1992 T7473
URI http://ethos.bl.uk/ProcessSearch.do?query=324108
System Number 000002796

Powered by Digitool Contact us Electronic Library Services Library Home