Abstract:
:High density particle image velocimetry, with spatial resolution of O(1 mm), was used to measure the effect of occluder rebound on the flow field near a Bjork-Shiley Monostrut tilting-disk mitral valve. The ability to measure two velocity components over an entire plane simultaneously provides a very different insight into the flow compared to the more traditional point to point techniques (like Laser Doppler Velocimetry) that were utilized in previous investigations of the regurgitant flow. A picture of the effects of occluder rebound on the fluid flow in the atrial chamber is presented. Specifically, fluid velocities in excess of 1.5 m/s traveling away from the atrial side were detected 3 mm away from the valve seat in the local low pressure region created by the occluder rebound on the major orifice side where cavitation has been observed. This analysis is the first spatially detailed flow description of the effects of occluder rebound on the flow field past a tilting-disk mechanical heart valve and further reinforces the hypothesis that the rebound effect plays a significant role in the formation of cavitation, which has been implicated in the hemolysis and wear associated with tilting-disk valves in vivo.
journal_name
Ann Biomed Engjournal_title
Annals of biomedical engineeringauthors
Kini V,Bachmann C,Fontaine A,Deutsch S,Tarbell JMdoi
10.1114/1.281subject
Has Abstractpub_date
2000-04-01 00:00:00pages
431-41issue
4eissn
0090-6964issn
1573-9686journal_volume
28pub_type
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