Impeller for catheter pump
An impeller for a pump is disclosed herein. The impeller can include a hub having a fixed end and a free end. The impeller can also have a plurality of blades supported by the hub. Each blade can have a fixed end coupled to the hub and a free end. The impeller can have a stored configuration and a deployed configuration, the blades in the deployed configuration extending away from the hub, and the blades in the stored configuration being compressed against the hub.
1. An impeller for a catheter pump, the impeller comprising:
a hub having a proximal end portion and a distal end portion; and
a single row of blades extending from the hub, the single row of blades comprising two or three blades, each blade transitionable between a stored position and a deployed position;
wherein each blade has a curved profile with a radius of curvature, and wherein the radius of curvature in the deployed position is approximately the same as the radius of curvature in the stored position.
2. The impeller of claim 1 , wherein, in the deployed position, the radius of curvature is larger when each blade is rotating than when each blade is stationary.
3. The impeller of claim 1 , wherein the radius of curvature is in a range from about 0.06 inches to about 0.155 inches.
4. The impeller of claim 1 , wherein the radius of curvature is in a range from about 0.09 inches to about 0.14 inches.
5. An impeller for a catheter pump, the impeller comprising:
a hub having a proximal end portion and a distal end portion; and
a single row of blades extending from the hub, the single row of blades comprising two or three blades, each blade transitionable between a stored position and a deployed position;
wherein each blade extends from a fixed end at the hub to an opposite free end, and wherein each blade has a varying thickness such that the blade is thinner at the fixed end than the free end.
6. The impeller of claim 5 , wherein, for at least one blade of the two or three blades, a thickness of a leading edge of the blade near the hub is in a range from 0.016 inches to 0.023 inches.
7. The impeller of claim 5 , wherein, for at least one blade of the two or three blades, a thickness of a leading edge of the blade near the free end is in a range from 0.022 inches to 0.028 inches.
8. The impeller of claim 5 , wherein, for at least one blade of the two or three blades, a thickness of a trailing edge of the blade near the hub is in a range from 0.016 inches to 0.023 inches.
9. The impeller of claim 5 , wherein, for at least one blade of the two or three blades, a thickness of a trailing edge of the blade near the hub is in a range from 0.03 inches to 0.04 inches.
10. An impeller for a catheter pump, the impeller comprising:
a hub having a proximal end portion and a distal end portion; and
a single row of blades extending from the hub, the single row of blades comprising two or three blades, each blade transitionable between a stored position and a deployed position;
wherein each blade of the plurality of blades wraps around the hub by a wrapping angle between about 150 degrees and about 220 degrees.
11. The impeller of claim 10 , wherein each blade of the plurality of blades wraps around the hub by a wrapping angle between about 180 degrees and about 200 degrees.
12. The impeller of claim 10 , wherein at least one blade of the plurality of blades has a wrapping angle of 210 degrees.
13. An impeller for a catheter pump, the impeller comprising:
a hub having a proximal end portion and a distal end portion; and
a single row of blades extending from the hub, the single row of blades comprising two or three blades, each blade transitionable between a stored position and a deployed position;
wherein each blade extends from a fixed end at the hub to an opposite free end and comprises:
a distal blade angle defined between a plane perpendicular to the free end of the blade near a distal end of the blade and a plane perpendicular to the hub;
a proximal blade angle defined between a plane perpendicular to the free end of the blade near a proximal end of the blade and a plane perpendicular to the hub; and
a middle blade angle defined between a plane perpendicular to the free end of the blade at a middle portion of the blade and a plane perpendicular to the hub, wherein the distal blade angle is larger than the middle blade angle, and wherein the middle blade angle is larger than the proximal blade angle.
14. The impeller of claim 13 , wherein the distal, proximal, and middle blade angles are selected to achieve relatively high flow rates at relatively low rotational speeds.
15. The impeller of claim 13 , wherein the distal, proximal, and middle blade angles are selected to achieve flow rates greater than 3.5 liters/minute.