Impeller for a rotary ventricular assist device

• US 8,419,609 B2
• Filed: 10/05/2005
• Issued: 04/16/2013
• Est. Priority Date: 10/05/2005
• Status: Active Grant

• Current Assignee: Heartware,Inc. (Medtronic Plc)
• Original Assignee: Heartware,Inc. (Medtronic Plc)
• Inventors: Shambaugh, Charles R. Jr., Trichi, Kartikeyan, LaRose, Jeffrey A.
• Primary Examiner(s): DIETRICH, JOSEPH M
• Application Number:
  US11/243,722
• Publication Number:
  US 20070078293A1
• Time in Patent Office: 2,750 Days
• Field of Search: 623/3.1, 623/3.13, 623/3.14, 623/3.15, 623/3.24, 623/3.29
• US Class Current: 600/16
• 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 60/196 replacing the entire heart, e.g. total artificial hearts [TAH]
• 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 60/419 the force acting on the blood contacting member being permanent magnetic, e.g. from a rotating magnetic coupling between driving and driven magnets
• CPC Class Codes: A61M 60/422 the force acting on the blood contacting member being electromagnetic, e.g. using canned motor pumps
• CPC Class Codes: A61M 60/508 Electronic control means, e.g. for feedback regulation
• CPC Class Codes: A61M 60/806 Vanes or blades
• CPC Class Codes: A61M 60/81 Pump housings
• CPC Class Codes: A61M 60/82 Magnetic bearings
• CPC Class Codes: A61M 60/824 Hydrodynamic or fluid film bearings
• CPC Class Codes: F04D 29/0476 for axial pumps
• CPC Class Codes: F04D 3/02 of screw type

Abstract

An impeller for a blood pump such as a magnetically driven, rotary ventricular assist device for pumping blood of a patient, the impeller being substantially entirely made of an alloy which consists essentially of about 70-80 weight percent of platinum and 20-30 weight percent of cobalt.

Claims

1. A magnetically driven rotary ventricular assist device implantable in a patient and configured to pump blood of the patient, said device comprising:

a rotatable body formed entirely of heat treated biocompatible magnetizable platinum and cobalt alloy, said rotatable body having a shape by which each of a plurality of blood flow channels formed therein is configured to direct blood traversing a channel away from said body when said body is rotating within the assist device, selected portions of said body of magnetizable alloy being subjected to magnetization establishing magnetic bearings for support of said body when said body is rotating within the ventricular assist device and for inducing north magnetic poles and south magnetic poles for effecting one or more of a magnetic drive mechanism and an axial or radial orientation of said body within the assist device while rotating.

2. The device of claim 1 which provides a centrifugal, pumped blood flow.

3. The device of claim 1 which provides an axial, pumped blood flow.

4. The device of claim 1, wherein said biocompatible magnetizable alloy consists essentially of about 70-80 weight percent of platinum and about 20-30 weight percent of cobalt.

5. The device of claim 4 in which said body is formed from 76-79 wt. percent of platinum.

6. The device of claim 1 in which land areas are formed on said rotatable body between said blood flow channels.

7. The device of claim 6 in which each of said land areas comprises at least one north or at least one south pole.

8. The device of claim 6 in which said land areas are each provided with alternating north and south poles.

9. A magnetically driven, rotary ventricular assist device, said device implantable in a patient and configured to pump blood of the patient, said device comprising:

a body formed entirely of biocompatible magnetizable alloy consisting essentially of about 70-80 weight percent of platinum and about 20-30 weight percent of cobalt, to enable strong electromagnetic coupling, said body of biocompatible magnetizable alloy being shaped to define a blood pumping impeller having a plurality of blood flow channels defining land areas therebetween, selected portions f said body of magnetizable alloy being subjected to magnetization whereby

said blood pumping impeller comprises a plurality of north poles and a plurality of south poles, said magnetization arranging at least one of said north poles or at least one of said south poles on each of said land areas.

10. The device of claim 9, in which the alloy of the impeller is in a heat-treated state for improved magnetic properties.

11. The device of claim 9, in which from essentially 76-79 weight percent of platinum is present in the alloy.

12. The device of claim 9, which provides a centrifugal, pumped blood flow.

13. The device of claim 9 which provides an axial, pumped blood flow.