Numerical study of squeeze-flow in tilting disc mechanical heart valves.
OBJECTIVE
The squeeze-flow that develops during valve closure is believed to cause cavitation in mitral mechanical heart valves (MHVs).


METHODS
Squeeze-flow was studied in tilting disc MHVs using two different numerical approaches. In the first decoupled analysis, experimental measurements of valve closing velocities were input into a computer model which simulated the resulting flow field. The second coupled approach involved simulation of the occluder motion and housing deformation in response to the surrounding flow.


RESULTS
Both models predicted the likelihood of cavitation during the squeeze-flow phase of valve closure. They also indicated that valve mounting compliance influences the squeeze-flow field. The coupled analysis also showed that squeeze-flow is influenced by fluid viscosity and the geometry of the contact region.


CONCLUSIONS
These parameters could therefore influence the inception of cavitation in tilting disc mitral MHVs.
Makhijani
V B
VB
CFD Research Corporation, Huntsville, AL 35805, USA.
Siegel
J M
JM
Hwang
N H
NH
D001696:Biomechanical Phenomena; D003196:Computer Graphics; D003198:Computer Simulation; D006350:Heart Valve Prosthesis / Q000706:statistics & numerical data*; D006439:Hemodynamics / Q000502:physiology*; D006801:Humans; D016013:Likelihood Functions; D008943:Mitral Valve / Q000503:physiopathology / Q000601:surgery*; D008955:Models, Cardiovascular; D009716:Numerical Analysis, Computer-Assisted; D011474:Prosthesis Design; D011475:Prosthesis Failure