Mechanically-foldable axial flow blood pump: response-surface-based structural optimization and hemolytic performance...

Area of Science:

• Biomedical Engineering
• Cardiovascular Devices
• Fluid Dynamics

Background:

• Traditional percutaneous ventricular assist devices (PVADs) require high rotational speeds, leading to significant hemolysis due to elevated shear stress.
• Design limitations of existing PVADs necessitate improvements for enhanced clinical applicability and reduced blood trauma.

Purpose of the Study:

• To design and optimize a foldable axial-flow blood pump with improved hydraulic efficiency and reduced hemolysis.
• To systematically analyze the influence of structural parameters on pump performance and blood trauma using numerical simulations.

Main Methods:

• Utilized numerical simulations and response surface methodology (RSM) with Box-Behnken Design (BBD) for parametric optimization.
• Analyzed the impact of key parameters including impeller and diffuser angles, and impeller-diffuser gap on pump head and hemolysis index (HI).

Main Results:

• Identified five critical structural parameters influencing pump head and HI.
• Achieved a 6.9% increase in head pressure and a 17.9% reduction in HI compared to the initial design through optimization.
• Demonstrated that increasing tip clearance reduces hemolysis with a moderate decrease in head.

Conclusions:

• Developed and optimized a foldable axial-flow blood pump for transaortic implantation with enhanced performance.
• The optimized pump configuration achieved a head of 2.346 m and an HI of $1.081\times 10^{-2}\%$ .
• Further adjustments in tip clearance can offer additional hemolysis reduction without significantly compromising pressure head, indicating potential for further clinical refinement.