Document Detail


Physiological flow simulation in residual human stenoses after coronary angioplasty.
MedLine Citation:
PMID:  11036553     Owner:  NLM     Status:  MEDLINE    
Abstract/OtherAbstract:
To evaluate the local hemodynamic implications of coronary artery balloon angioplasty, computational fluid dynamics (CFD) was applied in a group of patients previously reported by [Wilson et al. (1988), 77, pp. 873-885] with representative stenosis geometry post-angioplasty and with measured values of coronary flow reserve returning to a normal range (3.6 +/- 0.3). During undisturbed flow in the absence of diagnostic catheter sensors within the lesions, the computed mean pressure drop delta p was only about 1 mmHg at basal flow, and increased moderately to about 8 mmHg for hyperemic flow. Corresponding elevated levels of mean wall shear stress in the midthroat region of the residual stenoses, which are common after angioplasty procedures, increased from about 60 to 290 dynes/cm2 during hyperemia. The computations (Ree approximately equal to 100-400; alpha e = 2.25) indicated that the pulsatile flow field was principally quasi-steady during the cardiac cycle, but there was phase lag in the pressure drop-mean velocity (delta p - u) relation. Time-averaged pressure drop values, delta p, were about 20 percent higher than calculated pressure drop values, delta ps, for steady flow, similar to previous in vitro measurements by Cho et al. (1983). In the throat region, viscous effects were confined to the near-wall region, and entrance effects were evident during the cardiac cycle. Proximal to the lesion, velocity profiles deviated from parabolic shape at lower velocities during the cardiac cycle. The flow field was very complex in the oscillatory separated flow reattachment region in the distal vessel where pressure recovery occurred. These results may also serve as a useful reference against catheter-measured pressure drops and velocity ratios (hemodynamic endpoints) and arteriographic (anatomic) endpoints post-angioplasty. Some comparisons to previous studies of flow through stenoses models are also shown for perspective purposes.
Authors:
R K Banerjee; L H Back; M R Back; Y I Cho
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Publication Detail:
Type:  Journal Article; Validation Studies    
Journal Detail:
Title:  Journal of biomechanical engineering     Volume:  122     ISSN:  0148-0731     ISO Abbreviation:  J Biomech Eng     Publication Date:  2000 Aug 
Date Detail:
Created Date:  2001-01-24     Completed Date:  2001-02-01     Revised Date:  2004-11-17    
Medline Journal Info:
Nlm Unique ID:  7909584     Medline TA:  J Biomech Eng     Country:  UNITED STATES    
Other Details:
Languages:  eng     Pagination:  310-20     Citation Subset:  IM    
Affiliation:
Bioengineering and Physical Science Program, National Institute of Health (NIH), Bethesda, MD 20892, USA.
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MeSH Terms
Descriptor/Qualifier:
Angioplasty, Transluminal, Percutaneous Coronary*
Blood Flow Velocity / physiology
Blood Pressure
Coronary Angiography
Coronary Circulation / physiology*
Coronary Disease / physiopathology*,  radiography,  therapy*
Hemorheology*
Humans
Models, Cardiovascular*
Numerical Analysis, Computer-Assisted*
Pulsatile Flow
Recurrence
Treatment Outcome

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


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