Intimal hyperplasia and atherosclerosis have a predominant role in the failure of coronary artery bypass procedures. Theoretical studies and in vivo observations have shown that these pathologies are much more likely to occur in the proximity of end-to-side anastomosis, thus indicating that fluid dynamic conditions may be included in the pathogenic causes of the initiation, progression and complication of intimal hyperplasia. In order to study the fluid dynamics at the anastomosis of an aorto-coronary bypass, a three-dimensional mathematical model based on a FEM approach was developed. Steady-state simulations were studied in two different geometrical models of anastomosis which differ in their insertion angles (45 and 60 degree). Flow fields with three-dimensional helical patterns, secondary flows, and shear stresses were also investigated. The results show the presence of low shear stresses on the top wall just beyond the toe of the anastomosis and in the region of the coronary artery before the junction. A high wall shear stress region is present on the lateral wall of the coronary artery immediately downstream from the anastomosis. The influence of flow rate distribution on the secondary flows is also illustrated. These results confirm the sensitivity of flow behavior to the model’s geometrical parameters and enhance the importance of reproducing the anastomosis junction as closely as possible in order to evaluate the effective shear stress distribution.

1.
Bach
R. G.
,
Kern
M. J.
,
Donohue
T. J.
,
Aguirre
F. V.
, and
Caracciolo
E. A.
,
1993
, “
Comparison of Phasic Blood Flow Velocity Characteristics of Arterial and Venous Coronary Artery Bypass Conduits
,”
Circulation
, Vol.
88
, No.
5
, Part II, pp.
133
140
.
2.
Berne, R. M., Levy, M. N., 1981, Cardiovascular Physiology, CV Mosby Co., London.
3.
Caro
C. G.
,
Fitzgerald
J. M.
, and
Schroter
R. C.
,
1971
, “
Atheroma and Arterial Wall Shear Observations, Correlation and Proposal of a Shear Dependent Mass Transfer Mechanism for Atherogenesis
,”
Proc. R. Soc.
, Vol.
177
, pp.
109
159
.
4.
Campbell
P. C.
,
McGeachie
J. K.
, and
Prendergast
F. J.
,
1981
, “
Vein Grafts for Arterial Repair: Their Success and Reasons for failure
,”
Ann. R. Coll. Surg. Engl.
, Vol.
63
, pp.
257
260
.
5.
Clark
R. E.
,
Apostolous
S.
, and
Kardos
J. L.
,
1976
, “
Mismatch of Mechanical Proprieties as a Cause of Arterial Prosthesis Thrombosis
,”
Surg. Forum
, Vol.
27
, pp.
208
210
.
6.
Crawshaw
H. M.
,
Quist
W. C.
,
Serrallach
E.
,
Valeri
C. R.
, and
Logerfo
F. W.
,
1980
, “
Flow Disturbance at the Distal End-to-Side Anastomosis
,”
Arch. Surg.
, Vol.
115
, pp.
1280
1284
.
7.
Engelman
M. S.
,
1982
, “
FIDAP-A Fluid Dynamics Analysis Package
,”
Adv. Software Eng.
, Vol.
4
, pp.
163
163
.
8.
Fei
D-Y.
,
Thomas
J. D.
, and
Rittgers
S. E.
,
1994
, “
The Effect of Angle and Flow Rate Upon Hemodynamics in Distal Vascular Graft Anastomoses: A Numerical Model Study
,”
ASME JOURNAL OF BIOMECHANICAL ENGINEERING
, Vol.
116
, pp.
331
336
.
9.
Fry
D. L.
,
1969
, “
Certain Histological and Chemical Response of the Vascular Interface to Acutely Mechanical Stress in the Aorta of Dog
,”
Circ. Res.
, Vol.
24
, pp.
93
125
.
10.
Fung, Y. C., 1984, Biodynamics: Circulation, Springer-Verlag, New York.
11.
Giddens
D. P.
,
Zarins
C. K.
, and
Glagov
S.
,
1993
, “
The Role of Fluid Mechanics in the Localization and Detection of Atherosclerosis
,”
ASME JOURNAL OF BIOMECHANICAL ENGINEERING
, Vol.
115
, pp.
558
594
.
12.
Grondin
C. M.
,
1984
, “
Late Results of Coronary Artery Grafting: Is there a Flag on the Field?
,”
J. Thorac. Cardiovasc. Surg.
, Vol.
87
, pp.
161
166
.
13.
Hartman
C. W.
,
Kong
Y.
, and
Margolis
J. R.
, et al.,
1976
, “
Aortocoronary Bypass Surgery: Correlation of Angiographic, Symptomatic and Functional Improvement at 1 Year
,”
Am. J. Cardiol.
, Vol.
37
, pp.
352
357
.
14.
Imparato
A. M.
, and
Bracco
A.
et al.,
1972
, “
Intimal and Neointimal Fibrous Proliferation Causing Failure of Arterial Reconstruction
,”
Surgery
, Vol.
72
, pp.
1007
1017
.
15.
Kajiya
F.
,
Tsujioka
K.
,
Ogasawara
Y.
,
Wada
Y.
,
Matsuoka
S.
,
Kanazawa
S.
,
Hiramatsu
O.
,
Tadaoka
S.
,
Goto
M.
, and
Fujiwara
T.
,
1987
, “
Analysis of Flow Characteristics in Poststenotic Regions of the Human Coronary Artery during Bypass Graft Surgery
,”
Circulation
, Vol.
76
, pp.
1092
1100
.
16.
Keynton
R. S.
,
Rittgers
S. E.
and
Shu
M. C. S.
,
1991
, “
The Effect of Angle and Flow Rate Upon Hemodynamics in Distal Vascular Graft Anastomoses: An In Vitro Model Study
,”
ASME JOURNAL OF BIOMECHANICAL ENGINEERING
, Vol.
113
, pp.
458
463
.
17.
Ku
D. N.
,
Giddens
D. P.
,
Phillips
D. J.
, and
Strandness
D. E.
,
1985
, “
Hemodynamics of the Normal Human Carotid Bifurcation: In Vivo and In Vitro Studies
,”
Ultrasound Med. Biol.
, Vol.
11
, pp.
13
26
.
18.
Nazemi
N.
,
Kleinstreuer
C.
, and
Archie
J. P.
,
1990
, “
Pulsatile Two-Dimensional Flow in a Carotid Artery Bifurcation
,”
J. Biomechanics
, Vol.
23
, pp.
1013
1037
.
19.
Ojha
M.
,
Ethier
R. C.
,
Johnston
W. K.
, and
Cobbold
R. S. C.
,
1990
, “
Steady and Pulsatile Flow Fields in an End-to-Side Arterial Anastomosis Model
,”
J. Vasc. Surg.
, Vol.
12
, pp.
747
753
.
20.
Pietrabissa
R.
,
Inzoli
F.
, and
Fumero
R.
,
1990
, “
Simulation Study of the Fluid Dynamics of Aorto-Coronary Bypass
,”
J. Biomed. Eng.
, Vol.
12
, pp.
419
424
.
21.
Schettler, G., Nerem, R. N., Schmid-Scho¨nbein, H., Marl, H., and Diehm, C., 1983, Fluid Dynamics as a Localizing Factor for Atherosclerosis, Springer-Verlag, Berlin.
22.
Sottiurai
V. S.
,
Yao
J. S. T.
,
Flinn
W. R.
, and
Batson
R. C.
,
1983
, “
Intimal Hyperplasia and Neointima: An Ultrastructural Analysis of Thrombosed Grafts in Humans
,”
Surgery
, Vol.
93
, pp.
809
817
.
23.
Sottiurai
V. S.
,
Yao
J. S. T.
,
Batson
R. C.
,
Sue
S. L.
,
Jones
R.
, and
Nakamura
Y. A.
,
1989
, “
Distal Anastomotic Intimal Hyperplasia: Histopathological Character and Biogenesis
,”
Ann. Vasc. Surg.
, Vol.
1
, pp.
26
33
.
24.
Steinman
D. A.
,
Vinh
B.
,
Ethier
R. C.
,
Ojha
M.
,
Cobbold
R. S. C.
, and
Johnston
K. W.
,
1993
, “
A Numerical Simulation of Flow in a Two-Dimensional End-to-Side Anastomosis Model
,”
ASME JOURNAL OF BIOMECHANICAL ENGINEERING
, Vol.
115
, pp.
112
118
.
25.
Texon, M., 1980, Hemodynamics Basis of Atherosclerosis, Hemisphere, Washington, DC.
26.
Yoshida, Y., Yamaguchi, T., Caro, C. G., Glagov, S., and Nerem, R. M., 1988, Role of Blood Flow in Atherogenesis, Springer-Verlag.
27.
White
S. S.
,
Zarins
C. K.
,
Giddens
D. P.
,
Bassiouny
H.
,
Loth
F.
,
Jones
S. A.
, and
Glagov
S.
,
1993
, “
Hemodynamic Patterns in Two Models of End-to-Side Vascular graft Anastomoses: Effects of Pulsatility, Flow Division, Reynolds Number and Hood Length
,”
ASME JOURNAL OF BIOMECHANICAL ENGINEERING
, Vol.
115
, pp.
104
111
.
This content is only available via PDF.
You do not currently have access to this content.