Ultrasound heart catheters are used to measure the velocity in coronary arteries. However, the act of introducing a catheter into the vessel disturbs the very flow being measured. We used laser Doppler anemometry to measure the velocity distribution in an axially symmetric model, both with and without a catheter inserted. The catheter reduced the center-line velocity by as much as 60 percent at a distance of 2 mm downstream from the catheter, and by as much as 25 percent at a distance of 10 mm. This means the velocity measured with an ultrasound catheter does not show the maximum velocity of the undisturbed flow in the tube center. In the constriction, however, the measured velocities with the LDA and ultrasound catheter are almost the same. Thus, catheter measurements in the stenosis achieve accurate results. The velocity profile in the stenosed areas is flattened over nearly the whole cross section. The velocity is extremely reduced only close to the wall. The measurements outside of the stenosis lead to large differences which need to be studied carefully in the future. The disturbed flow finally disappeared 15 mm downstream of the catheter. The measurements were done at steady flow using a glycerine water solution with a dynamic viscosity of 4.35m Pas. In future studies, these experiments will be repeated for pulsatile flow conditions using non-Newtonian blood-like fluids.

1.
Durst, F., Melling, A., Whitelaw, J. H., Principles and Practice of Laser-Doppler-Anemometry, Academic Press, London, 1976.
2.
Ginn
A. L.
,
White
C. W.
, and
Wilson
R. F.
, “
Interstudy variability of Coronary Flow Reserve. Influence of Heart Rate, Arterial Pressure and Ventricular Preload
,”
Circulation
, Vol.
81
,
1990
, pp.
1319
1330
.
3.
Hartley
C. J.
, “
Review of Intracoronary Doppler Catheter
,”
Int. J. Card. Imaging
, Vol.
4
,
1980
, pp.
159
168
.
4.
Johnson
E. L.
,
Yock
P. G.
,
Hargrave
V. K.
,
Srebro
J. P.
,
Manubens
S. M.
,
Seitz
W.
, and
Ports
T. A.
, “
Assessment of Severity of Coronary Stenoses Using a Doppler Catheter. Validation of a Method Based on the Continuity Equation
,”
Circulation
, Vol.
80
,
1989
, pp.
625
635
.
5.
Kajiya, F., Ogasawara, Y., Kamazawa, S., Matsuoka, S., Hiramatsu, O., Tsujioka, K., and Kufiwara, T., “Normal and Stenotic Blood Flow Velocities in Human Left Coronary Artery Measured by an 80-Channel 20 MHz Pulsed Doppler Velocimeter,” Biofluid Mechanics—Blood Flow in Large Vessels, D. Liepsch, ed., Berlin, Springer, 1990, pp. 147–154.
6.
Ku
D. N.
, and
Giddens
D. P.
, “
Hemodynamics of the Normal Human Carotid Bifurcation: In Vitro and in Vivo Studies
,”
Ultrasound-Med-Biol
, Vol.
11
(
1
),
1985
, pp.
13
26
.
7.
Liepsch, D., “Untersuchungen der Stro¨mungsverha¨ltnisse in Verzweigungen von Rohren Kleiner Durchmesser (Coronararterien) bei Stromtrennung,” Diss. TU Mu¨nchen, 1974 und VDI-Berichte 232: 1975, pp. 423–442.
8.
Liepsch, D., “Stro¨mungsuntersuchungen an Modellen Menschlicher Blutgefa¨ß-Systeme,” Du¨sseldorf: VDI-Fortschrittsberichte Reihe 7: Stro¨mungstecnik. Nr. 113, 1986.
9.
Liepsch
D.
, “
Effect of Blood Flow Parameters on Flow Patterns at Arterial Bifurcations—Studies in Model
,”
Basel: Karger, Monographs on Atherosclerosis
, Vol.
15
,
1990
, pp.
63
76
.
10.
Liepsch, D., “Biofluid Mechanics—Blood Flow in Large Arteries,” Proceedings of the 2nd International Symposium on Biofluid Mechanics and Biorheology, Berlin, Springer, 1990.
11.
Loth, E., Ramamurti, R., Loth, F., and Jone, St., “Flow Downstream of an Ultrasound Catheter,” Proc. ASME 11th Winter Annual Meeting, BED Vol. 17, 1989.
12.
Qin
J. J.
,
Kuban
B. D.
,
Douglas
B.
,
van Fossen
D. B.
, and
Friedman
M. H.
, “
Evaluation of the Capabilities of a Steerable Ultra sound Doppler Catheter to Provide Quantitative Coronary Flow Indices
,”
1992 Advances in Bioengineering, Bidez, MW, ed.
, Vol.
2
,
1992
, pp.
395
398
.
13.
Sabbah
H. N.
,
Khaja
F.
,
Brymer
J. H.
,
Hawkins
E. T.
, and
Stein
P. D.
, “
Blood Velocity in the Right Coronary Artery: Relation to the Distribution of Atherosclerotic Lesions
,”
Am. J. Cardiol.
, Vol.
53
,
1984
, pp.
1008
1012
.
14.
Sibley
D. H.
,
Millar
H. D.
,
Hartley
C. J.
, and
Whitlow
P. L.
, “
Subselective Measurement of Coronary Blood Flow Velocity Using a Steerable Doppler Catheter
,”
J. Amer. Col. Cardiol.
, Vol.
8
,
1986
, pp.
1332
1349
.
15.
Voyles
W. F.
,
Greene
E. R.
,
Aetobelli
S. A.
, and
Hartley
C. J.
, “
In Vitro and In Vivo Studies Using a 4F Pulsed Doppler Velocimeter Catheter System
,”
Biomed. Sci. Instr.
, Vol.
20
,
1984
, pp.
17
23
.
16.
Wilson
R. F.
,
Johnson
M. R.
,
Marcus
M. L.
,
Aylward
P. E. G.
,
Skorton
D. J.
,
Collins
S.
, and
White
C. W.
, “
The Effect of Coronary Angioplasty on Coronary Flow Reverse
,”
Circulation
, Vol.
77
,
1988
, pp.
873
885
.
17.
Wilson
R. F.
,
Marcus
M. L.
, and
White
C. W.
, “
Prediction of the Physiologic Significance of Coronary Arterial Lesions by Quantitative Lesion Geometry in Patients with Limited Coronary Artery Disease
,”
Circulation
, Vol.
75
,
1987
, pp.
723
732
.
This content is only available via PDF.
You do not currently have access to this content.