An On-demand Morphing Impeller Pump for Low-Speed, Hemocompatible pVADs.

Area of Science:

• Biomedical Engineering
• Cardiovascular Devices
• Medical Innovation

Background:

• Percutaneous ventricular assist devices (pVADs) are crucial for acute cardiogenic shock.
• Current pVADs face limitations due to small delivery profiles for femoral access, restricting impeller size and increasing hemolysis risk.
• This necessitates higher rotational speeds, compromising device safety and efficiency.

Purpose of the Study:

• To introduce the Morphing Flexible Impeller Pump (MFP), a novel pVAD designed to overcome the size-performance trade-off.
• To demonstrate the MFP's ability to transition from a catheter-deliverable size to a larger, more efficient pumping configuration in situ.
• To evaluate the MFP's hemodynamic performance and hemolysis risk compared to existing technologies.

Main Methods:

• Development of the MFP with an integrated deployable linkage system enabling in situ morphing.
• Utilizing computational fluid dynamics (CFD) to analyze shear stresses and flow patterns.
• Conducting in vitro experiments to assess hemolysis indices under matched hemodynamic conditions.

Main Results:

• The MFP successfully transitioned from a 7 mm to a 16 mm diameter configuration.
• Achieved a clinically relevant pressure gradient of 10 mmHg at 4000 rpm, with lower speeds than typical micro-axial pumps.
• CFD analysis indicated shear stresses mostly below the hemolysis threshold, and in vitro tests showed comparable hemolysis indices to the Impella CP.

Conclusions:

• The morphing-impeller strategy effectively decouples delivery size from pumping capacity in pVADs.
• The MFP demonstrates a promising approach for safer and more efficient minimally invasive circulatory support.
• This technology has the potential to significantly improve outcomes for patients with acute cardiogenic shock.