Ventricular assist devices having a hollow rotor and methods of use

A method of providing supplemental blood flow to a patient, the method comprising:

• receiving an input blood flow from a patient into an inlet of a blood pump;
• generating a rotating magnetic field via a motor stator disposed around an annular blood flow channel in fluid communication with the blood pump inlet, the annular blood flow channel extending around a central flow stator;
• impelling blood through the annular blood flow channel by rotating a hollow rotor via the rotating magnetic field;
• the hollow rotor having a rotor inlet, a rotor outlet, and a rotor circumferential wall extending between the rotor inlet and the rotor outlet and enclosing a rotor blood flow channel through which the rotor inlet and the rotor outlet are in fluid communication;
• the hollow rotor having at least one rotor blade extending inwardly from the rotor circumferential wall;
• the at least one rotor blade being configured to impel blood through the rotor blood flow channel when the hollow rotor is rotated via the rotating magnetic field, the central flow stator at least partially extending through the rotor blood flow channel;
• and
• outputting the blood impelled through the hollow rotor to the patient via an outlet of the blood pump in fluid communication with the rotor outlet.

A blood pump of a ventricular assist device, the blood pump comprising:

• a housing having a housing inlet, a housing outlet, and a housing blood flow channel through which the housing inlet and the housing outlet are in fluid communication;
• a motor stator disposed around the housing blood flow channel and operable to generate a rotating magnetic field;
• a hollow rotor disposed within the housing blood flow channel and rotated via the rotating magnetic field;
• the hollow rotor having a rotor inlet, a rotor outlet, and a rotor circumferential wall extending between the rotor inlet and the rotor outlet and enclosing a rotor blood flow channel through which the rotor inlet and the rotor outlet are in fluid communication;
• the hollow rotor comprising at least one rotor blade extending inwardly from the rotor circumferential wall, the at least one rotor blade being configured to impel blood through the rotor blood flow channel when the hollow rotor is rotated via the rotating magnetic field;
• and
• at least one permanent magnet coupled with the hollow rotor and configured to interact with the rotating magnetic field so as to rotate the hollow rotor within the housing blood flow channel, the rotor circumferential wall being configured to accommodate and support the at least one permanent magnet between the rotor blood flow channel and an inner surface of the housing blood flow channel,
• wherein the motor stator comprises a plurality of pole pieces magnetically coupled to a common back piece, a plurality of drive coils for generating the rotating magnetic field, and a plurality of levitation coils to generate magnetic fields to levitate the hollow rotor;
• each of the plurality of pole pieces passing through one of the plurality of drive coils and one of the plurality of levitation coils, and
• wherein each of the plurality of drive coils is wrapped around a single one of the plurality of pole pieces and each of the plurality of levitation coils is wrapped around an adjacent two of the plurality of pole pieces.