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Flow visualization in anatomically accurate, flow-through models of the main pulmonary artery trunk

Published online by Cambridge University Press:  19 August 2008

Sheri L. Carroll
Affiliation:
From the Departments of Pediatrics, Universizy of North Carolina, Chapel Hill
Hiroshi Katayama*
Affiliation:
From the Departments of Pediatrics, Universizy of North Carolina, Chapel Hill
G. William Henry
Affiliation:
From the Departments of Pediatrics, Universizy of North Carolina, Chapel Hill
Jose I. Ferreiro
Affiliation:
From the Departments of Pediatrics, Universizy of North Carolina, Chapel Hill
Rudy Zalesak
Affiliation:
Biomedical Engineering, Universizy of North Carolina, Chapel Hill
Belinda Ha
Affiliation:
Biomedical Engineering, Universizy of North Carolina, Chapel Hill
Carol L. Lucas
Affiliation:
Biomedical Engineering, Universizy of North Carolina, Chapel Hill
Megha Singh
Affiliation:
The Indian Institute of Technology, Madras
Patricia G. Lynch
Affiliation:
Georgia Institute of Technology, Atlanta
Ajit P. Yoganathan
Affiliation:
Georgia Institute of Technology, Atlanta
*
GB 7220, 311 Burnett-Womack, 229H, University of North Carolina, Chapel Hill, NC 27599-7220, USA. Tel. 919-966-4601; Fax. 919-966-9893.

Abstract

To study the effect of maturational geometric changes on flow characteristics in the pulmonary artery trunk, anatomically accurate, acrylic flow-through models were constructed from four flexible silicone rubber casts obtained in situ in lambs weighing 2.4, 7.8, 9.5, and 11.5 kg. A silicone rubber cast of the right heart was fabricated by injecting the superior caval vein in situ with liquid silicone rubber (Dow Corning's HS-II RTV, Midland, MI). Each cast was used as a template for a transparent acrylic mold of the pulmonary artery trunk and primary generation branches. The acrylic block was then fitted with a curved rigid Plexiglass inflow tube (to simulate the curvature of the right ventricle) just proximal to the pulmonary valve sinuses and mounted in a closed loop system driven by a variable speed pulsatile pump (to simulate physiological flow rates between 0.5 and 4.0 lmin−1) A blood analog solution of polystyrene beads (Rohm & Haas Amberlite, Philadelphia, PA) suspended in a 45% by weight glycerine solution was illuminated by a laser source (15 mwatts, Siemens, Germany) to trace the flow patterns. Two flow field planes of the main pulmonary artery trunk—one parallel, and one perpendicular, to the origins of the right and left arterial branches—were visualized and video recorded (Canon H660 8mm, Japan) for subsequent analysis. A prominent vortex, originating in the center of the main pulmonary artery and directed inferiorly toward the inner wall, was noted in the flow field plane perpendicular to the bifurcation in the 9.5 and 11.5 models. These characteristics were less developed in the 7.8 kg model and not present in the 2.4 kg model, possibly because the angle of curvature was less acute than in the larger models. In the flow field plane parallel to the bifurcation, the patterns were more complex, principally influenced by turbulence in the main pulmonary artery (which increased at higher flow rates) and the geometric changes in the branch pulmonary arteries.

Type
Original Articles
Copyright
Copyright © Cambridge University Press 1992

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References

1.Liepsch, DW. Flow in tubes and arteries—A comparison. Biorheology. 1986; 23: 395433.CrossRefGoogle ScholarPubMed
2.Kilner, PJ, Ho, SY, Anderson, RH. Cardiovascular cavities cast in silicone rubber as an adjunct to post-mortem examination of the heart. Int J Cardiol 1989; 22: 99107.CrossRefGoogle ScholarPubMed
3.Sung, HW, Yoganathan, AP. Axial flow velocity patterns in a normal human pulmonary artery model: Pulsatile in vitro studies. J Biomechanics 1990; 23: 201214.CrossRefGoogle Scholar
4.Frantz, EG, Henry, GW, Lucas, CL, Keagy, BA, Lores, ME, Criado, E, Ferreiro, JI, Wilcox, BR. Characteristics of blood flow velocity in the hypertensive canine pulmonary artery. Ultrasound Med Biol 1986; 12: 379385.CrossRefGoogle ScholarPubMed
5.Lucas, CL, Henry, GW, Ferreiro, JI, Ha, B, Keagy, BA, Wilcox, BR. Pulmonary blood velocity profile variability in open-chest dogs: Influence of acutely altered hemodynamic states on profiles and influence of profiles on the accuracy of techniques for cardiac output determination. Heart Vessels 1988; 4: 6578.CrossRefGoogle ScholarPubMed
6.Lucas, CL, Henry, GW, Ha, B, Ferreiro, JI, Frantz, EG, Wilcox, BR. Characterization of pulmonary artery blood velocity patterns in lambs. In: 2 International Symposium on Biofluid Mechanics & Biorhelolgy. Berlin, Springer-Verlag, 1990, pp 171184.Google Scholar
7.Okamoto, M, Miyatake, K, Kinoshita, N, Sakakibara, H, Nimura, Y. Analysis of blood flow in pulmonary hypertension with the pulsed Doppler flowmeter combined with cross sectional echocardiography. Br Heart J 1984; 51: 407415.CrossRefGoogle ScholarPubMed
8.Karayama, H, Henry, GW, Lucas, CL, Ha, B, Ferreiro, JI, Frantz, EG, Krzeski, R. Three-dimensional visualization ofpulmonary blood flow velocity profiles in lambs. Jpn Heart J [In Press]Google Scholar
9.den, Bos van GC, Westerhof, N, Randall, OS. Pulse wave reflection: Can it explain the differences between systemic and pulmonary pressure and flow waves? Circ Res 1982; 51: 479485.Google Scholar
10.Chandran, KB, Yearwood, TL, Wieting, DW. An experimental study of pulsatile flow in a curved tube. J Biomechanics 1979; 12: 793805.CrossRefGoogle Scholar
11.Yearwood, TL, Chandran, KB. Experimental investigation of steady flow through a model of the human aortic arch. J Biomechanics 1980; 13: 10751088.CrossRefGoogle Scholar
12.Farthing, S, Peronneau, P. Flow in the thoracic aorta. Cardiovasc Res 1979; 13: 607620.CrossRefGoogle ScholarPubMed
13.Philpot, E, Yoganathan, AP, Sung, HW, Woo, YR, Franch, RH, Sahn, DJ, and Valdez-Cruz, L. In-vitro pulsatile flow visualiza tion studies in a pulmonary artery model. J Biomech Eng 1985; 107: 368375.CrossRefGoogle Scholar
14.Fukushima, T, Homma, T, Azuma, T, Harakawa, K. Character istics of secondary flow in steady and pulsatile flows through a symmetrical bifurcation. Biorheology 1987; 24: 312.CrossRefGoogle Scholar
15.Singh, M, Lucas, CL, Henry, GW, Ferreiro, JI, and Wilcox, BR. Three-dimensional visualization of the influence of an aneu rysm on flow through curved vessels Presented at the Sixth International Conference onBiomedical EngineeringSingapore, 1990.Google Scholar