Abstract:
:In a healthy human cardiac system, a large asymmetric clockwise vortex present in the left ventricle (LV) efficiently diverts the filling jet from the mitral annulus to the left ventricular outflow track. However, prior clinical studies have shown that artificial mitral valve replacement can affect the formation of physiological vortex, resulting in overall flow instability in the LV. Lately, the findings from several recent hemodynamic studies seem to suggest that the native D-shaped mitral annulus might be a crucial factor in the development of this physiological flow pattern, with its inherent flow stability and formation of coherent structures within the LV. This study aims to investigate the effect of orifice shape and its position with respect to the posterior wall of the ventricle on vortical formation and turbulence intensity in the LV, by utilizing four separate orifice configurations within an in vitro left heart simulator. Stereo particle image velocimetry experiments were then carried out to characterize the downstream flow field of each configuration. Our findings demonstrate that the generation of the physiological left ventricular vortical flow was not solely dependent upon the orifice shape but rather the subsequent jet-wall interaction. The distance of the orifice geometric center from the left ventricular posterior wall plays a significant role in this jet-wall interaction, and thus, vortical flow dynamics.
journal_name
Artif Organsjournal_title
Artificial organsauthors
Tan SG,Hon JKF,Nguyen YN,Kim S,Leo HLdoi
10.1111/aor.13781subject
Has Abstractpub_date
2020-12-01 00:00:00pages
e520-e531issue
12eissn
0160-564Xissn
1525-1594journal_volume
44pub_type
杂志文章abstract::An increasing amount of evidence points to cerebral embolization during cardiopulmonary bypass (CPB) as the principal etiologic factor of neurologic complications. In this study, the capability of capturing and classification of gaseous emboli and pressure drop of three different membrane oxygenators (Sorin Apex, Teru...
journal_title:Artificial organs
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journal_title:Artificial organs
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更新日期:2011-05-01 00:00:00
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journal_title:Artificial organs
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journal_title:Artificial organs
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journal_title:Artificial organs
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