Document Detail


The closing velocity of mechanical heart valve leaflets.
MedLine Citation:
PMID:  7858776     Owner:  NLM     Status:  MEDLINE    
Abstract/OtherAbstract:
The closing motion of the occluder leaflets in bileaflet type mechanical heart valves (MHV) was monitored with a laser sweeping technique. The angular displacements of the leaflets were registered with precision of 0.2 microsecond steps. Experimental measurements were made using five 29 mm Edwards-Duromedics including three original specification (EDOS) and two modified specification (EDMS), and two 29 mm St Jude Medical MHVs. The testing valve was installed in the mitral position of a physiologic pulsatile mock circulatory flow loop using water-glycerine solution as the testing fluid. Each valve was tested by: (1) direct mounting the valve on metal washers, and (2) mounting the valve with its sewing ring. Experiments were carried out at pulse rates of 70, 90, and 120 beats min-1, with the corresponding cardiac output of 5, 6, and 7.5 litres min-1, and maximum left ventricular pressure gradients (dp/dt) of 1,800, 3,000 and 5,600 mm Hg s-1, respectively. The maximum leaflet closing velocity of each of the tested valve types are presented. The difference in leaflet closing movements between the direct rigid mounting and the sewing ring mounting are discussed. The details of the laser sweeping technique are presented.
Authors:
G X Guo; T H Chiang; R C Quijano; N H Hwang
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Publication Detail:
Type:  Journal Article    
Journal Detail:
Title:  Medical engineering & physics     Volume:  16     ISSN:  1350-4533     ISO Abbreviation:  Med Eng Phys     Publication Date:  1994 Nov 
Date Detail:
Created Date:  1995-03-23     Completed Date:  1995-03-23     Revised Date:  2004-11-17    
Medline Journal Info:
Nlm Unique ID:  9422753     Medline TA:  Med Eng Phys     Country:  ENGLAND    
Other Details:
Languages:  eng     Pagination:  458-64     Citation Subset:  IM    
Affiliation:
Baxter Healthcare Corporation, Edwards Cardiovascular Surgery Division, Irvine, California 92714.
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MeSH Terms
Descriptor/Qualifier:
Biomechanics
Blood Flow Velocity*
Blood Pressure
Cardiac Output
Heart Valve Prosthesis / classification,  standards*
Humans
Laser-Doppler Flowmetry
Materials Testing
Mitral Valve
Models, Cardiovascular
Pulsatile Flow
Rotation
Signal Processing, Computer-Assisted

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine


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