Article Comprising an Impeller

• US 20090062597A1
• Filed: 08/29/2008
• Published: 03/05/2009
• Est. Priority Date: 08/29/2007
• Status: Active Grant

• Current Assignee: FBR Medical, Inc.
• Original Assignee: Medical Value Partners, LLC
• Inventors: Shifflette, J. Michael
• Granted Patent: US 8,079,948 B2
• Time in Patent Office: Days
• US Class Current: 600/16
• CPC Class Codes: A61M 60/13 by means of a catheter allowing explantation, e.g. catheter pumps temporarily introduced via the vascular system
• CPC Class Codes: A61M 60/148 in line with a blood vessel using resection or like techniques, e.g. permanent endovascular heart assist devices
• CPC Class Codes: A61M 60/221 the blood flow through the rotating member having both radial and axial components, e.g. mixed flow pumps
• CPC Class Codes: A61M 60/237 the blood flow through the rotating member having mainly axial components, e.g. axial flow pumps
• CPC Class Codes: A61M 60/414 transmitted by a rotating cable, e.g. for blood pumps mounted on a catheter
• CPC Class Codes: A61M 60/808 specially adapted for deformable impellers, e.g. expandable impellers
• CPC Class Codes: F04D 29/181 Axial flow rotors F04D29/185 take precedence
• CPC Class Codes: F04D 29/247 elastic or self-adjusting
• CPC Class Codes: F04D 29/382 Flexible blades
• CPC Class Codes: F04D 3/00 Axial-flow pumps priming or boosting F04D9/00
• CPC Class Codes: F04D 3/02 of screw type

Abstract

An impeller for use in conjunction with a percutaneously-insertable blood pump or other rotatable equipment includes a blade that is segmented into a plurality of overlapping or abutting bladelets. In some embodiments, the bladelets are foldable and one side of each bladelet is concave.

Claims

1. An impeller comprising:

a hub; and

a first plurality of bladelets disposed on the hub, wherein the first plurality of bladelets collectively define a first blade, wherein each bladelet has a root, a tip, a pressure face and a suction face, and further wherein;

(a) each bladelet is movable between a deployed state in which the tip thereof is relatively further from the hub and a non-deployed state in which the tip is relatively closer to the hub;

(b) the pressure face of each bladelet is concave; and

(c) the root of each bladelet is narrower than the tip of each bladelet.

2. The impeller of claim 1 further comprising a second plurality of bladelets disposed on the hub, wherein the second plurality of bladelets collectively define a second blade, and wherein the first plurality of bladelets and the second plurality of bladelets are diametrically opposed about the hub, the first and second blade collectively defining a first blade row.

3. The impeller of claim 1 wherein the first plurality of bladelets are helically arranged about the hub.

4. The impeller of claim 1 wherein the suction face of each bladelet is convex.

5. The impeller of claim 1 wherein a ratio of chord length of the tip to the chord length of the root is at least about 1.5.

6. The impeller of claim 1 wherein a ratio of a span of each bladelet to a chord length of the tip of each bladelet is at least about two.

7. The impeller of claim 1 wherein respective tips of adjacent bladelets abut each other.

8. The impeller of claim 1 wherein leading and trailing peripheral edges of each bladelet are straight.

9. The impeller of claim 1 further comprising a membrane, wherein the membrane covers at least a portion of the first blade.

10. A single-stage impeller comprising a single blade row:

a hub;

a first blade depending from the hub; and

a second blade depending from the hub and diametrically opposed to the first blade, wherein;

(a) the blade row comprises the first blade and the second blade;

(b) the first blade and the second blade are segmented into bladelets, each bladelet having a root, a tip, and a pressure face;

(c) the bladelets are widest at the tip thereof and narrowest at the root;

(d) each bladelet is foldable proximate to the root thereof; and

(e) the pressure face of each bladelet is concave.

11. The impeller of claim 10 wherein the bladelets that define the first blade are helically arranged about the hub.

12. The impeller of claim 10 wherein respective roots of adjacent bladelets are spaced apart from one another.

13. The impeller of claim 10 wherein respective tips of adjacent bladelets overlap.

14. The impeller of claim 10 wherein respective tips of adjacent bladelets abut each other.

15. The impeller of claim 10 further comprising a first membrane and a second membrane, wherein the first membrane covers at least a portion of the first blade and the second membrane covers at least a portion of the second blade.

16. An impeller comprising:

a hub; and

a first plurality of bladelets disposed on the hub, wherein the first plurality of bladelets collectively define a first blade, wherein each bladelet has a root and a tip, and further wherein each bladelet is movable between a deployed state in which the tip thereof is relatively further from the hub and a non-deployed state in which the tip is relatively closer to the hub.

17. The impeller of claim 16 wherein at least some of the bladelets are widest at the tip and narrowest at the root thereof.

18. The impeller of claim 16 wherein each bladelet has a pressure face and a suction face, and further wherein the pressure face of at least some of the bladelets is concave.

19. The impeller of claim 16 wherein each bladelet has a pressure face and a suction face, and further wherein the suction face of at least some of the bladelets is convex.

20. The impeller of claim 16 wherein the first plurality of bladelets are helically arranged about the hub.

21. The impeller of claim 16 wherein a membrane covers at least a portion of the first blade.

22. The impeller of claim 16 further comprising a second plurality of bladelets disposed on the hub, wherein the second plurality of bladelets collectively define a second blade, wherein the first and second blade collectively define a first blade row, and wherein the first blade row exhibits n-fold symmetry, wherein n is the number of blades in the first blade row.

23. The impeller of claim 16 wherein the tip of adjacent bladelets abut each other.

24. The impeller of claim 16 wherein the tip of adjacent bladelets overlap each other.

25. A temporary cardiac-assist device, comprising:

a flexible drive cable;

a rigid drive shaft, wherein the flexible drive cable and the rigid drive shaft are coupled to one another;

an impeller hub, wherein the impeller hub is operatively coupled to the drive shaft; and

a first plurality of individually-movable bladelets disposed on the impeller hub, wherein the first plurality of bladelets collectively define a first blade, and wherein each bladelet is movable between a deployed state in which a tip thereof is relatively further from the hub and a non-deployed state in which the tip is relatively closer to the hub.

26. The cardiac-assist device of claim 25 wherein the tip of adjacent bladelets abut each other.

27. The cardiac-assist device of claim 25 wherein the tip of adjacent bladelets overlap each other.

28. The cardiac-assist device of claim 25 wherein a root of each bladelet is narrower than the tip of each bladelet.

29. The cardiac-assist device of claim 25 wherein each bladelet has a pressure face and a suction face, and wherein, in operation, the pressure face experiences a higher pressure than the suction face, and further wherein the pressure face of at least some of the bladelets is concave.

30. The cardiac-assist device of claim 25 wherein at least some of the bladelets are widest at the tip and narrowest at the root thereof.

31. The cardiac-assist device of claim 25 wherein the first plurality of bladelets are helically arranged about the hub.

32. The cardiac-assist device of claim 25 further comprising a second plurality of bladelets disposed on the hub, wherein the second plurality of bladelets collectively define a second blade, wherein the first and second blade collectively define a first blade row, and wherein the first blade row exhibits n-fold symmetry, wherein n is the number of blades in the first blade row.

33. The cardiac-assist device of claim 25 further comprising a membrane, wherein the membrane covers at least a portion of the first blade.