Ambulatory energy transfer system for an implantable medical device and method therefore

• US 20050075698A1
• Filed: 04/30/2004
• Published: 04/07/2005
• Est. Priority Date: 10/02/2003
• Status: Active Grant

• Current Assignee: Medtronic Incorporated (Medtronic Plc)
• Original Assignee: Medtronic Incorporated (Medtronic Plc)
• Inventors: Phillips, William C., Olson, David P., Schmeling, Andrew L., Schommer, Mark E., Elvidge, Michael J.
• Granted Patent: US 7,515,967 B2
• Time in Patent Office: Days
• US Class Current: 607/61
• CPC Class Codes: A61N 1/3787 from an external energy source

Abstract

An external power system, system and method for transcutaneous energy transfer to an implantable medical device having componentry for providing a therapeutic output and a secondary coil operatively coupled to the componentry. The implantable medical device is adapted to implanted at a location in a patient. An external power source has a primary coil contained in a housing. The external power source is capable of providing energy to the implantable medical device when the primary coil of the external power source is placed in proximity of the secondary coil of the implantable medical device. A holder is adapted to be externally positioned with respect to the patient at a spot in proximity of the location of the implantable medical device and secured at the spot. The holder is attachable to the housing after the holder is secured to the patient.

Claims

1. An external power system for transcutaneous energy transfer to an implantable medical device having componentry for providing a therapeutic output and a secondary coil operatively coupled to said componentry, said implantable medical device adapted to be implanted at a location in a patient, comprising:

an external power source having a primary coil contained in a housing;

said external power source capable of providing energy to said implantable medical device when said primary coil of said external power source is placed in proximity of said secondary coil of said implantable medical device; and

a holder adapted to be externally positioned with respect to said patient at a spot in proximity of said location of said implantable medical device and secured at said spot;

said holder being attachable to said housing after said holder is secured to said patient.

2. An external power system as in claim 1 wherein said holder has a surface closest to said implantable medical device and wherein said surface is tacky with respect to said patient.

3. An external power system as in claim 2 wherein said surface has a durometer of about 40 Shore A.

4. An external power system as in claim 1 further comprising a belt coupled to said holder and adapted to secure said holder to said patient.

5. An external power system as in claim 1 wherein said holder comprises:

a flexible body portion having a central opening; and

a pair of pivot points positioned laterally on either side of a central axis;

said pair of pivot points facilitating pivotal attachment of said housing to said holder.

6. An external power system as in claim 1 wherein said external power source further comprises a repositionable magnetic core located in said housing.

7. An external power system as in claim 1 wherein a surface of said housing closest to said secondary coil is thermally conductive.

8. An external power system as in claim 7 wherein said external power source further comprises a temperature sensor thermally coupled to said surface of said housing.

9. An external power system as in claim 8 wherein said external power source further comprises circuitry coupled to said temperature sensor operative to limit said energizing at least in part as a function of said temperature.

10. An external power system as in claim 1 wherein said external power further comprises circuitry, operatively coupled to said primary coil, capable of inductively energizing said secondary coil by driving said primary coil at a carrier frequency when said primary coil of said external power source is externally placed in proximity of said secondary coil creating a tuned inductive circuit having a resonant frequency;

said circuitry adjusting said carrier frequency to said resonant frequency.

11. An external power system as in claim 1 wherein said external power further comprises circuitry, operatively coupled to said primary coil, capable of inductively energizing said secondary coil by driving said primary coil at a carrier frequency when said primary coil of said external power source is externally placed in proximity of said secondary coil creating a tuned inductive circuit having an impedance;

said circuitry adjusting said carrier frequency to minimize said impedance.

12. An external power system as in claim 1 wherein said external power further comprises circuitry, operatively coupled to said primary coil, capable of inductively energizing said secondary coil by driving said primary coil at a carrier frequency when said primary coil of said external power source is externally placed in proximity of said secondary coil creating a tuned inductive circuit having an energy transfer efficiency;

said circuitry adjusting said carrier frequency to increase said energy transfer efficiency of said inductively tuned circuit.

13. An external power system as in claim 1 wherein said implantable medical device has a rechargeable power source operatively couple to said secondary coil and to said componentry.

14. A system for transcutaneous energy transfer, comprising:

an implantable medical device having componentry for providing a therapeutic output and a secondary coil operatively coupled to said componentry, said implantable medical device adapted to implanted at a location in a patient an external power source having a primary coil contained in a housing;

said external power source capable of providing energy to said implantable medical device when said primary coil of said external power source is placed in proximity of said secondary coil of said implantable medical device; and

a holder adapted to be externally positioned with respect to said patient at a spot in proximity of said location of said implantable medical device and secured at said spot;

said holder being attachable to said housing after said holder is secured to said patient.

15. A system as in claim 14 wherein said holder has a surface closest to said implantable medical device and wherein said surface is tacky with respect to said patient.

16. A system as in claim 15 wherein said surface has a durometer of about 40 Shore A.

17. A system as in claim 14 further comprising a belt coupled to said holder and adapted to secure said holder to said patient.

18. A system as in claim 14 wherein said holder comprises:

a flexible body portion having a central opening; and

a pair of pivot points positioned laterally on either side of a central axis;

said pair of pivot points facilitating pivotal attachment of said housing to said holder.

19. A system as in claim 14 wherein said external power source further comprises a repositionable magnetic core located in said housing.

20. A system as in claim 14 wherein a surface of said housing closest to said secondary coil is thermally conductive.

21. A system as in claim 20 wherein said external power source further comprises a temperature sensor thermally coupled to said surface of said housing.

22. A system as in claim 21 wherein said external power source further comprises circuitry coupled to said temperature sensor operative to limit said energizing at least in part as a function of said temperature.

23. A system as in claim 14 wherein said external power further comprises circuitry, operatively coupled to said primary coil, capable of inductively energizing said secondary coil by driving said primary coil at a carrier frequency when said primary coil of said external power source is externally placed in proximity of said secondary coil creating a tuned inductive circuit having a resonant frequency;

said circuitry adjusting said carrier frequency to said resonant frequency.

24. A system as in claim 14 wherein said external power further comprises circuitry, operatively coupled to said primary coil, capable of inductively energizing said secondary coil by driving said primary coil at a carrier frequency when said primary coil of said external power source is externally placed in proximity of said secondary coil creating a tuned inductive circuit having an impedance;

said circuitry adjusting said carrier frequency to minimize said impedance.

25. A system as in claim 14 wherein said external power further comprises circuitry, operatively coupled to said primary coil, capable of inductively energizing said secondary coil by driving said primary coil at a carrier frequency when said primary coil of said external power source is externally placed in proximity of said secondary coil creating a tuned inductive circuit having an energy transfer efficiency;

said circuitry adjusting said carrier frequency to increase said energy transfer efficiency of said inductively tuned circuit.

26. A system as in claim 14 wherein said implantable medical device has a rechargeable power source operatively couple to said secondary coil and to said componentry.

27. A method of transcutaneous energy transfer from an external power source having a primary coil contained in a housing to an implantable medical device having componentry for providing a therapeutic output and a secondary coil operatively coupled to said componentry, said implantable medical device adapted to implanted at a location in a patient, comprising the steps of:

placing a holder with respect to said patient at a spot in proximity of said location of said implantable medical device;

securing said holder at said spot; and

then attaching said housing to said holder.

28. An external power system as in claim 27 wherein said holder has a surface closest to said implantable medical device and wherein said surface is tacky with respect to said patient.

29. A method as in claim 28 wherein said surface has a durometer of about 40 Shore A.

30. A method as in claim 27 wherein said securing step is accomplished using a belt coupled to said holder.

31. A method as in claim 27 wherein said attaching step comprises pivotally attaching said housing to said holder.

32. A method as in claim 27 further comprising the step of repositioning a magnetic core located in said housing to improve efficiency of said transcutaneous energy transfer.

33. A method as in claim 27 wherein a surface of said housing closest to said secondary coil is thermally conductive.

34. A method as in claim 33 further comprising the step of limiting said energizing at least in part as a function of a temperature of a temperature sensor thermally coupled to said surface of said housing.

35. A method as in claim 27 further comprising the step of adjusting a carrier frequency of said primary coil inductively driving said secondary coil, forming a tuned inductive circuit having a resonant frequency, to said resonant frequency of said tuned inductive circuit.

36. A method as in claim 27 further comprising the step of adjusting a carrier frequency of said primary coil inductively driving said secondary coil, forming a tuned inductive circuit having an impedance, to minimize said impedance of said tuned inductive circuit.

37. A method as in claim 27 further comprising the step of adjusting a carrier frequency of said primary coil inductively driving said secondary coil, forming a tuned inductive circuit having an energy transfer efficiency, to increase said energy transfer efficiency of said tuned inductive circuit.

38. A method as in claim 27 wherein said implantable medical device has a rechargeable power source operatively couple to said secondary coil and to said componentry.