Background and aim of the study: 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.