| abstract |
A blood pump for assisting a heart is provided by a stator and a rotor. The rotor is magnetically supported creating a suspension gap between the stator and the rotor. The rotor can be supported axially by a Lorentz force bearing and can be magnetically rotated. The stator can have a volute pump chamber and the rotor can have an impeller portion for pumping blood. The rotor can have a center bore as a primary blood flowpath. The suspension gap can be a first retrograde blood flowpath. An axial gap between the impeller and the volute housing can be a second retrograde blood flowpath. The blood pump can also have an axial position controller. The axial position controller can cause the axial bearing to adjust the position of the rotor. The axial position of the rotor. The axial position of the magnetic suspension components can be adjusted to compensate for changes in the magnetic fields of the magnetic suspension components. The blood pump can also have a flow rate controller. The flow rate controller can have a member for measuring a dimension of a heart ventricle to control the flow rate to avoid overly distending or contracting the ventricle. A method for operating the flow rate controller to create a pulsatile flow rate is also provided. A flow sensor can be used to avoid excessively low or reverse blood flow through the pump when a pulsatile flow rate is provided. |