Blood pump with separate mixed-flow and axial-flow impeller stages, components therefor and related methods

An implantable blood pump comprising:

• including a stator housing having a diverging inlet and a converging outlet and defining a fluid pathway from the inlet to the outlet;
• a rotor including a rotor hub disposed within the stator housing and defining an annulus between the rotor hub and the stator housing, the rotor hub having a diameter between approximately 12 to 13 millimeters, a leading portion proximate the inlet, a trailing portion proximate the outlet, and an intermediate portion spanning between the leading portion and the trailing portion;
• a plurality of first stage impeller blades coupled to the leading portion of the rotor hub;
• a plurality of second stage impeller blades coupled to the intermediate portion of the rotor hub, the plurality of second stage impeller blades defining an impeller blade clearance between each of the plurality of second stage impeller blades and the stator housing;
• and
• a plurality of stator vanes extending from the stator housing proximate the outlet and defining a stator vane clearance between each of the plurality of stator vanes and the rotor hub, the impeller blade clearance being of a length less than a length of the stator vane clearance.

An implantable blood pump configured to provide continuous fluid flow comprising:

• including a stator housing having a diverging inlet and a converging outlet;
• a rotor including a rotor hub defining an annulus between the rotor hub and the stator housing, the rotor hub configured to rotate at a speed of approximately 14,000 rotations per minute and having:
• a diameter between 12 to 13 millimeters;
• a leading portion proximate the inlet including a mixed-flow first stage impeller blade coupled thereto;
• a trailing portion proximate the outlet;
• an intermediate portion spanning between the leading portion and the trailing portion, the intermediate portion including an axial-flow second stage impeller blade coupled thereto, the axial-flow second stage impeller blade defining an impeller blade clearance between the rotor hub and the stator housing within the annulus;
• and
• a stator vane extending from the stator housing proximate the outlet and defining a stator vane clearance between the stator vane and the rotor hub;
• and
• including the impeller blade clearance being of a length less than a length of the stator vane clearance.