VentrAssist hydrodynamically suspended, open, centrifugal blood pump

Area of Science:

• Biomedical Engineering
• Cardiovascular Devices
• Fluid Dynamics

Background:

• Current implantable blood pumps often have limitations such as mechanical wear, potential for blood clots due to stagnant zones, and hemolysis.
• The absence of traditional components like shafts, seals, and spiders in blood pumps can lead to improved biocompatibility and reduced risk of complications.

Purpose of the Study:

• To present a novel design for an implantable centrifugal blood pump.
• To utilize hydrodynamic forces for impeller suspension, thereby eliminating the need for a mechanical shaft.
• To evaluate the performance of this novel design in terms of hemolysis and system efficiency.

Main Methods:

• A novel centrifugal blood pump design was developed, featuring thick blades with tapered edges.
• Hydrodynamic forces acting on the blade edges were employed to levitate and suspend the impeller.
• The pump's performance was assessed by measuring hemolysis levels and system efficiency at a flow rate of 5 L/min and a differential pressure of 100 mm Hg.

Main Results:

• The novel blood pump design successfully suspended the impeller using hydrodynamic forces.
• The pump demonstrated minimal hemolysis, with measured values in the range of NIH 0.002-0.005 g/100 L.
• The system achieved an efficiency of 19% at the tested operating conditions (5 L/min, 100 mm Hg differential pressure).
• The design features clean flow lines with no stagnant zones, enhancing hemocompatibility.

Conclusions:

• The presented shaftless, seal-less centrifugal blood pump design offers a promising alternative for mechanical circulatory support.
• The hydrodynamic suspension mechanism effectively minimizes blood-cell damage (hemolysis) and avoids stagnant flow regions.
• Further research and development could optimize this design for clinical application in treating heart failure.