Document Detail


Effect of a flow-streamlining implant at the distal anastomosis of a coronary artery bypass graft.
MedLine Citation:
PMID:  12398422     Owner:  NLM     Status:  MEDLINE    
Abstract/OtherAbstract:
Intimal thickening in the coronary artery bypass graft (CABG) distal anastomosis has been implicated as the major cause of restenosis and long-term graft failure. Several studies point to the interplay between nonuniform hemodynamics including disturbed flows and recirculation zones, wall shear stress, and long particle residence time as possible etiologies. The hemodynamic features of two anatomic models of saphenous-vein CABGs were studied and compared. One simulated an anastomosis with both diameter and compliance mismatch and a curvature at the connection, analogous to the geometry observed in a conventional cardiothoracic procedure. The other, simulated an anastomosis with a flow stabilizing anastomotic implant connector which improves current cardiothoracic procedures by eliminating the distal vein bulging and curvature. Physiologic flow conditions were imposed on both models and qualitative analysis of the flow was performed with dye injection and a digital camera. Quantitative analysis was performed with laser Doppler velocimetry. Results showed that the presence of the bulge at the veno-arterial junction, contributed to the formation of accentuated secondary structures (helices), which progress into the flow divider and significantly affect radial velocity components at the host vessel up to four diameters downstream of the junction. The model with the implant, achieved more hemodynamically efficient conditions on the host vessel with higher mean and maximum axial velocities and lower radial velocities than the conventional model. The presence of the sinus may also affect the magnitude and shape of the shear stress at locations where intimal thickening occurs. Thus, the presence of the implant creates a more streamlined environment with more primary and less secondary flow components which may then inhibit the development of intimal thickening, restenosis, and ultimate failure of the saphenous vein graft.
Authors:
Andreas S Anayiotos; Pedro D Pedroso; Evangelos C Eleftheriou; Ramakrishna Venugopalan; William L Holman
Publication Detail:
Type:  Comparative Study; Evaluation Studies; Journal Article; Research Support, Non-U.S. Gov't    
Journal Detail:
Title:  Annals of biomedical engineering     Volume:  30     ISSN:  0090-6964     ISO Abbreviation:  Ann Biomed Eng     Publication Date:    2002 Jul-Aug
Date Detail:
Created Date:  2002-10-25     Completed Date:  2003-04-23     Revised Date:  2006-11-15    
Medline Journal Info:
Nlm Unique ID:  0361512     Medline TA:  Ann Biomed Eng     Country:  United States    
Other Details:
Languages:  eng     Pagination:  917-26     Citation Subset:  IM    
Affiliation:
Department of Biomedical Engineering, University of Alabama at Birmingham, 35294-4440, USA. aanayiot@eng.uab.edu
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MeSH Terms
Descriptor/Qualifier:
Arteriovenous Anastomosis / physiopathology*,  surgery
Blood Flow Velocity
Blood Pressure
Blood Vessel Prosthesis*
Coronary Artery Bypass / instrumentation,  methods*
Coronary Vessels / physiopathology*,  surgery
Equipment Failure Analysis / methods*
Hemorheology / methods*
Humans
Laser-Doppler Flowmetry
Nickel
Pulsatile Flow
Saphenous Vein / transplantation
Sensitivity and Specificity
Shear Strength
Stress, Mechanical
Titanium
Chemical
Reg. No./Substance:
12035-60-8/titanium nickelide; 7440-02-0/Nickel; 7440-32-6/Titanium

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


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