Lumped parameter model for computing the minimum pressure during mechanical heart valve closure

Area of Science:

• Biomedical Engineering
• Fluid Dynamics
• Cardiovascular Science

Background:

• Cavitation inception in mechanical heart valves is highly variable.
• Existing hypotheses lack consistent scaling laws due to complex dynamic conditions.

Purpose of the Study:

• To develop a model predicting the minimum pressure during mechanical heart valve closure.
• To assess the impact of varied closure conditions on cavitation inception.

Main Methods:

• Developed a system of ordinary differential equations solved numerically.
• Conducted experiments in a mock circulatory loop with a bileaflet valve.
• Utilized high-speed video and high-response pressure measurements for validation.

Main Results:

• The simulation model showed good agreement with experimental closing dynamics and minimum pressure trends.
• The model predicts the variability observed in experimental cavitation inception.
• Lumped parameter model serves as a valuable engineering assessment tool.

Conclusions:

• The developed model accurately predicts cavitation inception thresholds in mechanical heart valves.
• Initial and final leaflet closure conditions are key drivers of cavitation variability.
• The model offers a predictable approach to understanding cavitation in prosthetic heart valves.