The abdominal aortic aneurysm (AAA) is a significant cause of death and disability in the Western world and is the subject of many clinical and pathological studies. One of the most commonly used surrogates of the human AAA is the angiotensin II (Ang II) induced model used in mice. Despite the widespread use of this model, there is a lack of knowledge concerning its hemodynamics; this study was motivated by the desire to understand the fluid dynamic environment of the mouse AAA. Numerical simulations were performed using three subject-specific mouse models in flow conditions typical of the mouse. The numerical results from one model showed a shed vortex that correlated with measurements observed in vivo by Doppler ultrasound. The other models had smaller aneurysmal volumes and did not show vortex shedding, although a recirculation zone was formed in the aneurysm, in which a vortex could be observed, that elongated and remained attached to the wall throughout the systolic portion of the cardiac cycle. To link the hemodynamics with aneurysm progression, the remodeling that occurred between week one and week two of the Ang II infusion was quantified and compared with the hemodynamic wall parameters. The strongest correlation was found between the remodeled distance and the oscillatory shear index, which had a correlation coefficient greater than 0.7 for all three models. These results demonstrate that the hemodynamics of the mouse AAA are driven by a strong shear layer, which causes the formation of a recirculation zone in the aneurysm cavity during the systolic portion of the cardiac waveform. The recirculation zone results in areas of quiescent flow, which are correlated with the locations of the aneurysm remodeling.

References

References
1.
Norman
,
P. E.
, and
Powell
,
J. T.
, 2010, “
Site Specificity of Aneurysmal Disease
,”
Circulation
,
121
(
4
), pp.
560
568
.
2.
Golledge
,
J.
,
Muller
,
J.
,
Daugherty
,
A.
, and
Norman
,
P.
, 2006, “
Abdominal Aortic Aneurysm: Pathogenesis and Implications for Management
,”
Arterioscler. Thromb. Vasc. Biol.
,
26
(
12
), pp.
2605
2613
.
3.
Isselbacher
,
E. M.
, 2005, “
Thoracic and Abdominal Aortic Aneurysms
,”
Circulation
,
111
(
6
), pp.
816
828
.
4.
Kuivaniemi
,
H.
,
Platsoucas
,
C. D.
, and
Tilson
,
M. D.
, 2008, “
Aortic Aneurysms: An Immune Disease With a Strong Genetic Component
,”
Circulation
,
117
(
2
), pp.
242
252
.
5.
McCormick
,
M. L.
,
Gavrila
,
D.
, and
Weintraub
,
N. L.
, 2007, “
Role of Oxidative Stress in the Pathogenesis of Abdominal Aortic Aneurysms
,”
Arterioscler. Thromb. Vasc. Biol.
,
27
(
3
), pp.
461
469
.
6.
Thompson
,
R. W.
, 2002. “
Reflections on the Pathogenesis of Abdominal Aortic Aneurysms
,”
Cardiovasc. Surg.
,
10
(
4
), pp.
389
394
.
7.
Vorp
,
D. A.
, and
Vande Geest
,
J. P.
, 2005, “
Biomechanical Determinants of Abdominal Aortic Aneurysm Rupture
,”
Arterioscler. Thromb. Vasc. Biol.
,
25
(
8
), pp.
1558
1566
.
8.
Daugherty
,
A.
, and
Cassis
,
L. A.
, 2004, “
Mouse Models of Abdominal Aortic Aneurysms
,”
Arterioscler. Thromb. Vasc. Biol.
,
24
(
3
), pp.
429
434
.
9.
Daugherty
,
A.
,
Manning
,
M. W.
, and
Cassis
,
L. A.
, 2000, “
Angiotensin II Promotes Atherosclerotic Lesions and Aneurysms in Apolipoprotein E-Deficient Mice
,”
J. Clin. Invest.
,
105
(
11
), pp.
1605
1612
.
10.
Daugherty
,
A.
,
Rateri
,
D. L.
, and
Cassis
,
L. A.
, 2006, “
Role of the Renin-Angiotensin System in the Development of Abdominal Aortic Aneurysms in Animals and Humans
,”
Ann. NY Acad. Sci.
,
1085
, pp.
82
91
.
11.
Yu
,
S.
, 2000, “
Steady and Pulsatile Flow Studies in Abdominal Aortic Aneurysm Models Using Particle Image Velocimetry
,”
Int. J. Heat Fluid Flow
,
21
(
1
), pp.
74
83
.
12.
Yip
,
T.
, and
Yu
,
S.
, 2001, “
Cyclic Transition to Turbulence in Rigid Abdominal Aortic Aneurysm Models
,”
Fluid Dyn. Res.
,
29
(
2
), pp.
81
113
.
13.
Taylor
,
T. W.
, and
Yamaguchi
,
T.
, 1994, “
Three-Dimensional Simulation of Blood Flow in an Abdominal Aortic Aneurysmsteady and Unsteady Flow Cases
,”
ASME J. Biomech. Eng.
,
116
(
1
), pp.
89
97
.
14.
Sheard
,
G. J.
, 2009, “
Flow Dynamics and Wall Shear-Stress Variation in a Fusiform Aneurysm
,”
J. Eng. Math.
,
64
(
4
), pp.
379
390
.
15.
Finol
,
E. A.
,
Keyhani
,
K.
, and
Amon
,
C. H.
, 2003, “
The Effect of Asymmetry in Abdominal Aortic Aneurysms Under Physiologically Realistic Pulsatile Flow Conditions
,”
ASME J. Biomech. Eng.
,
125
(
2
), pp.
207
217
.
16.
Bluestein
,
D.
,
Niu
,
L.
,
Schoephoerster
,
R. T.
, and
Dewanjee
,
M. K.
, 1996, “
Steady Flow in an Aneurysm Model: Correlation Between Fluid Dynamics and Blood Platelet Deposition
,”
ASME J. Biomech. Eng.
,
118
(
3
), pp.
280
286
.
17.
Humphrey
,
J. D.
, and
Taylor
,
C. A.
, 2008, “
Intracranial and Abdominal Aortic Aneurysms: Similarities, Differences, and Need for a New Class of Computational Models
,”
Annu. Rev. Biomed. Eng.
,
10
, pp.
221
246
.
18.
Les
,
A. S.
,
Shadden
,
S. C.
,
Figueroa
,
C. A.
,
Park
,
J. M.
,
Tedesco
,
M. M.
,
Herfkens
,
R. J.
,
Dalman
,
R. L.
, and
Taylor
,
C. A.
, 2010, “
Quantification of Hemodynamics in Abdominal Aortic Aneurysms During Rest and Exercise Using Magnetic Resonance Imaging and Computational Fluid Dynamics
,”
Ann. Biomed. Eng.
,
38
(
4
), pp.
1288
1313
.
19.
O’Rourke
,
M. J.
, and
McCullough
,
J. P.
, 2008, “
A Comparison of the Measured and Predicted Flowfield in a Patient Specific Model of an Abdominal Aortic Aneurysm
,”
Proc. Inst. Mech. Eng., Part H: J. Eng. Med.
,
222
(
5
), pp.
737
750
.
20.
Cao
,
R. Y.
,
St. Amand
,
T.
,
Ford
,
M. D.
,
Piomelli
,
U.
, and
Funk
,
C.
, 2010, “
The Murine Angiotensin II–Induced Abdominal Aortic Aneurysm Model: Rupture Risk and Inflammatory Progression Patterns
,”
Front. Pharmacol.
1
, pp.
1
7
.
21.
Antiga
,
L.
,
Piccinelli
,
M.
,
Botti
,
L.
,
Ene-Iordache
,
B.
,
Remuzzi
,
A.
, and
Steinman
,
D. A.
, 2008, “
An Image-Based Modeling Framework for Patient-Specific Computational Hemodynamics
,”
Med. Biol. Eng. Comput.
,
46
(
11
), pp.
1097
112
.
22.
Weller
,
H.
,
Tabor
,
G.
,
Jasak
,
H.
, and
Fureby
,
C.
, 1998, “
A Tensorial Approach to Computational Continuum Mechanics Using Object-Oriented Techniques
,”
Comput Phys.
,
12
(
6
), pp.
620
631
.
23.
Amirbekian
,
S.
,
Long
,
R. C.
,
Consolini
,
M. A.
,
Suo
,
J.
,
Willett
,
N. J.
,
Fielden
,
S. W.
,
Giddens
,
D. P.
,
Taylor
,
W. R.
, and
Oshinski
,
J. N.
, 2009, “
In Vivo Assessment of Blood Flow Patterns in Abdominal Aorta of Mice With MRI: Implications for AAA Localization
,”
Am. J. Physiol. Heart Circ. Physiol.
,
297
(
4
), pp.
1290
1295
.
24.
Womersley
,
J.
, 1955, “
Method for the Calculation of Velocity, Rate of Flow and Viscous Drag in Arteries When the Pressure Gradient is Known
,”
J. Physiol.
,
127
(
3
), pp.
553
563
.
25.
Kim
,
J.
, and
Moin
,
P.
, 1985, “
Application of a Fractional Step Method to Incompressible Navier-Stokes Equations
,”
J. Comp. Phys.
,
59
(
2
), pp.
308
323
.
26.
Ford
,
M. D.
,
Nikolov
,
H. N.
,
Milner
,
J. S.
,
Lownie
,
S. P.
,
Demont
,
E. M.
,
Kalata
,
W.
,
Loth
,
F.
,
Holdsworth
,
D. W.
, and
Steinman
,
D. A.
, 2008, “
PIV-Measured Versus CFD-Predicted Flow Dynamics in Anatomically Realistic Cerebral Aneurysm Models
,”
ASME J. Biomech. Eng.
,
130
(
2
), p.
021015
.
27.
Robinson
,
S. K.
, 1991, “
Coherent Motions in the Turbulent Boundary Layer
,”
Annu. Rev. Fluid Mech.
,
21
(
1
), pp.
601
639
.
28.
Jou
,
L. D.
,
Wong
,
G.
,
Dispensa
,
B.
,
Lawton
,
M. T.
,
Higashida
,
R. T.
,
Young
,
W. L.
, and
Saloner
,
D.
, 2005, “
Correlation Between Lumenal Geometry Changes and Hemodynamics in Fusiform Intracranial Aneurysms
,”
Am. J. Neuroradiol.
,
26
(
9
), pp.
2357
2363
.
29.
Lee
,
S. W.
,
Antiga
,
L.
, and
Steinman
,
D. A.
, 2009, “
Correlations Among Indicators of Disturbed Flow at the Normal Carotid Bifurcation
,”
ASME J. Biomech. Eng.
,
131
(
6
), p.
061013
.
30.
Ford
,
M. D.
,
Piomelli
,
U.
,
Cao
,
R. Y.
,
Funk
,
C.
, and
Pollard
,
A.
, 2010, “
Numerical Simulations of the Intra-Aneurismal Vortex Shedding in Induced Mouse Abdominal Aortic Aneurysms
,” No. FEDSM-ICNMM2010-30546,
ASME 2010 3rd joint US-European Fluids Engineering Summer Meeting
.
You do not currently have access to this content.