Prototype Continuous Flow Ventricular Assist Device Supported on Magnetic Bearings.

Area of Science:

• Biomedical Engineering
• Mechanical Engineering
• Fluid Dynamics

Background:

• Continuous flow pumps are essential in medical devices.
• Magnetic bearings offer advantages like reduced friction and no need for lubrication.
• Previous designs faced challenges with size and efficiency.

Purpose of the Study:

• To describe a prototype continuous flow ventricular assist device (CFVAD2) utilizing magnetic bearings.
• To evaluate the performance and characteristics of the magnetic bearing system in the pump.
• To assess the potential for miniaturization and blood compatibility.

Main Methods:

• The CFVAD2 prototype was tested in a simulated adult human circulation system.
• Magnetic bearing parameters (load capacity, current gains) were analyzed.
• Rotor forces were estimated in air and water across various orientations.
• Hemolysis levels were measured to assess blood cell damage.

Main Results:

• The pump achieved 6 L/min flow at 100 mm Hg differential pressure head.
• Magnetic bearings (2 radial, 2 thrust) supported the rotor effectively.
• Measured forces were lower than anticipated, enabling future size reduction.
• Hemolysis levels indicated no significant damage to blood cells.

Conclusions:

• The magnetic bearing-supported CFVAD2 prototype demonstrates viable performance for medical use.
• The low force measurements suggest a significant opportunity for developing a more compact device.
• The pump exhibits good hemocompatibility, crucial for blood-contacting applications.