In vitro flow dynamics of four prosthetic aortic valves: a comparative analysis.
The velocity fields downstream of four prosthetic heart valves were mapped in vitro over the entire cross-section of a model aortic root using laser Doppler anemometry. THe Björk-Shiley 60 degrees convexo-concave tilting disc valve, the Smeloff-Cutter caged ball valve, the St. Jude Medical bileaflet valve, and the Ionescu-Shiley standard bioprosthesis were examined under both steady and pulsatile flows. Velocity profiles under steady flow conditions were a good approximation for pulsatile profiles only during midsystole. The pulsatile flow characteristics of the four valves showed variation in large scale flow structures. Comparison of the valves according to pressure drop, shear stress and maximum velocities are also provided.
Hanle
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DD
Chemical Engineering Laboratory, California Institute of Technology, Pasadena 91125.
Harrison
E C
EC
Yoganathan
A P
AP
Allen
D T
DT
Corcoran
W H
WH
D001021:Aortic Valve; D001705:Bioprosthesis; D001783:Blood Flow Velocity; D001794:Blood Pressure; D006350:Heart Valve Prosthesis; D006801:Humans; D008955:Models, Cardiovascular; D011474:Prosthesis Design; D012039:Regional Blood Flow; D012212:Rheology; D013314:Stress, Mechanical