System and method of bridging a transreceiver coil of an implantable medical device during non-communication periods

• US 6,510,345 B1
• Filed: 04/24/2000
• Issued: 01/21/2003
• Est. Priority Date: 04/24/2000
• Status: Expired due to Term

• Current Assignee: Medtronic Incorporated (Medtronic Plc)
• Original Assignee: Medtronic Incorporated (Medtronic Plc)
• Inventors: Van Bentem, Maarten M. P. E.
• Primary Examiner(s): Schaetzle, Kennedy
• Application Number:
  US09/556,454
• Time in Patent Office: 1,002 Days
• Field of Search: 607/60, 607/30, 607/31, 607/32, 128/903, 128/901
• US Class Current: 607/60
• CPC Class Codes: A61N 1/37 Monitoring; Protecting
• CPC Class Codes: A61N 1/3718 Monitoring of or protection against external electromagnetic fields or currents
• CPC Class Codes: A61N 1/37223 Circuits for electromagnetic coupling
• CPC Class Codes: A61N 1/37252 Details of algorithms or data aspects of communication system, e.g. handshaking, transmitting specific data or segmenting data
• CPC Class Codes: A61N 1/37254 Pacemaker or defibrillator security, e.g. to prevent or inhibit programming alterations by hackers or unauthorised individuals

Abstract

The present invention discloses a method of and a system for preventing unwanted alternating current magnetic fields transmitted from an external source from disrupting electrical circuitry within an implantable medical device, while permitting desired communications between the implantable medical device and a programmer detected in proximity to the implantable medical device. The implantable medical device is capable of communication with at least one implantable lead position within a heart of a patient. The method includes activating an electrical device to create a short circuit in parallel with an inductive transreceiver coil of the implantable medical device, thereby shorting out the inductor transreceiver coil. In this mode, alternating current magnetic fields do not effect electrical circuitry within the implantable medical device. The method further includes detecting a direct current magnetic field indicating the presence of a programmer located in proximity to the implantable medical device. The electrical device shorting out the inductive transreceiver coil is deactivated and thereby opened during detection of the presence of the programmer in proximity to the implantable medical device such that the implantable medical device and the programmer can communicate via the inductive transreceiver coil.

Claims

1. A method of preventing unwanted alternating current (AC) magnetic fields transmitted from an external source from disrupting electrical circuitry within an implantable medical device, while permitting desired communications between the implantable device and a programmer, the method comprising:

activating an electrical device within the implantable medical device electrically coupled in parallel with an inductive transceiver coil, thereby providing a short circuit in parallel with the inductive transreceiver coil during non-detection of the programmer in proximity to the implantable medical device by activating an electrical device within the implantable medical device electrically coupled in parallel with an inductive transceiver coil;

deactivating the electrical device during detection of the presence of the programmer in proximity to the implantable medical device, thereby providing an open circuit in parallel with the inductive transreceiver coil by activating an electrical device within the implantable medical device electrically coupled in parallel with an inductive transceiver coil; and

communicating between the implantable medical device and the proximally located programmer.

2. The method of claim 1, wherein activating the electrical device further comprises:

closing a switch electrically coupled in parallel with the inductive transreceiver coil, thereby shorting out the inductive transreceiver coil.

3. The method of claim 1, wherein activating the electrical device further comprises:

providing current to a metal oxide semiconductor device such that a low impedance path is created in parallel with the inductive transreceiver coil.

4. The method of claim 1, wherein activating the electrical device further comprises:

providing current to a bipolar junction transistor such that a low impedance path is provided in parallel with the inductive transreceiver coil.

5. The method of claim 1, wherein activating the electrical device further comprises:

providing current to a junction field effect transistor such that a low impedance path is provided in parallel with the inductive transreceiver coil.

6. The method of claim 1, wherein activating the electrical device further comprises:

providing current to a thyristor such that a low impedance path is provided in parallel with the inductive transreceiver coil.

7. The method of claim 1, wherein activating the electrical device further comprises:

providing current to a triac such that a low impedance path is provided in parallel with the inductive transreceiver coil.

8. The method of claim 1, wherein activating the electrical device further comprises:

providing current to a Reedswitch such that a low impedance path is provided in parallel with the inductive transreceiver coil.

9. The method of claim 1, wherein activating the electrical device further comprises:

providing an electrical signal from a programmer detector of the implantable medical device to the electrical device indicating a lack of presence of the programmer proximal to the implantable medical device.

10. The method of claim 1, wherein deactivating the electrical device further comprises:

providing an electrical signal from a program detector of the implantable medical device to the electrical device indicating the presence of a programmer in proximity to the implantable medical device.

11. The method of claim 1, wherein deactivating the electrical device further comprises:

deactivating the electrical device during detection of the presence of a direct current magnetic field radiating from the programmer.

12. The method of claim 1, wherein communicating between the implantable medical device and the programmer further comprises:

transmitting information stored within the implantable medical device to the programmer via the inductive transreceiver coil.

13. The method of claim 1, wherein communicating between the implantable medical device and the programmer further comprises:

transmitting information to the implantable medical device from the programmer via the inductive transreceiver coil.

14. The method of claim 1, further comprising providing the implantable medical device with at least one implanatable medical electrical lead, the lead being suitable for positioning within a heart of a patient, the medical device being capable of communication with the at least one implantable lead.

15. A method of providing a communication path between an implantable medical device located within a patient and a programmer located in proximity to the implantable medical device, the implantable medical device capable of interacting with at least on e implantable lead positioned within a heart of a patient, the method comprising:

detecting a programmer located in proximity to the implantable medical device;

deactivating a low impedance device connected in parallel with an inductive transreceiver coil to electrical circuitry of the implantable medical device, the low impedance device deactivated in response to the detection of a proximally located programmer; and

wherein the inductive transreceiver coil facilitates communication between the implantable medical device and the programmer.

16. The method of claim 15, wherein detecting the programmer located in proximity to the implantable medical device further comprises:

detecting a direct current magnetic field radiating from the programmer in proximity to the implantable medical device.

17. The method of claim 15, wherein deactivating the low impedance device further comprises:

opening a switch connected in parallel with the inductive transreceiver coil, thereby creating an open circuit.

18. The method of claim 15, wherein deactivating the low impedance device further comprises:

providing current to a metal oxide semiconductor device such that the metal oxide semiconductor device acts as an open circuit in parallel with the inductive transreceiver coil.

19. The method of claim 15, wherein deactivating the low impedance device further comprises:

providing current to a bipolar junction transistor such that the bipolar junction transistor acts as an open circuit in parallel with an inductor transreceiver coil.

20. The method of claim 15, wherein deactivating the low impedance device further comprises:

providing current to a junction field effect transistor such that the junction field effect transistor acts as an open circuit in parallel with an inductor transreceiver coil.

21. The method of claim 15, wherein deactivating the low impedance device further comprises:

providing current to a thyristor such that the thyristor acts as an open circuit in parallel with an inductor transreceiver coil.

22. The method of claim 15, wherein deactivating the low impedance device further comprises:

providing current to a triac such that the triac acts as an open circuit in parallel with an inductor transreceiver coil.

23. The method of claim 15, wherein deactivating the low impedance device further comprises:

providing current to a Reedswitch such that the Reedswitch acts as an open circuit in parallel with an induct or transreceiver coil.

24. The method of claim 15, wherein deactivating the low impedance device further comprises:

altering a signal provided to the low impedance device such that the low impedance device acts as an open circuit.

25. The method of claim 15, further comprising:

activating the low impedance device in response to an absence of detection of a proximally located programmer.

26. An implantable medical device capable of interacting with at least one implantable lead positioned within a heart of a patient, the implantable medical device also capable of communicating with a programmer located in proximity to the implantable medical device, the implantable medical device comprising:

a power source;

a programmer detector for detecting a presence of the programmer in proximity to the implantable medical device;

a communication system for communicating with the programmer;

an inductive transreceiver coil electrically coupled to the communication system for facilitating communication with the programmer; and

a switch electrically coupled to the programmer detector and to the communication system in parallel with the inductive transreceiver coil, the switch opened in the presence of the programmer, thereby creating a communication path between the programmer and the communication system of the implantable medical device via the inductive transreceiver coil.

27. The implantable medical device of claim 26, wherein the programmer detector further comprises:

a detection switch which closes when the programmer detector detects the presence of the programmer in proximity to the implantable medical device, thereby providing a signal to the switch electrically coupled in parallel with the inductive transreceiver coil which causes the switch to open, thereby producing an open circuit.

28. The implantable medical device of claim 26, wherein the programmer detector further comprises:

a Hall sensor which senses a direct current magnetic filed radiating from the programmer when the programmer is located in proximity to the implantable medical device.

29. The method of claim 26, wherein the programmer detector further comprises:

a Reedswitch which closes when the programmer detector senses a direct current magnetic field radiating from the programmer indicating that the programmer is located in proximity to the implantable medical device.

30. The implantable medical device of claim 26, wherein the communications system further comprises:

a transreceiver capable of transmitting information between the implantable medical device and the programmer via the inductive transreceiver coil.

31. The implantable medical device of claim 26, wherein the inductive transreceiver coil facilitates transmission of inductive signals between the implantable medical device and the programmer.

32. The implantable medical device of claim 26, wherein the inductive transreceiver coil facilitates transmission of magnetically coupled signals between the implantable medical device and the programmer.

33. The implantable medical device of claim 26, wherein the inductive transreceiver coil receives data signals from the programmer.

34. The implantable medical device of claim 26, wherein the inductive transreceiver coil further comprises:

an aircoil.

35. The implantable medical device of claim 26, wherein the inductive transreceiver coil further comprises:

a ferrite coil.

36. The implantable medical device of claim 26, wherein the switch electrically coupled to the programmer detector and to the communication system further comprises:

a metal oxide semiconductor device.

37. The implantable medical device of claim 26, wherein the switch electrically coupled to the programmer detector and to the communication system further comprises:

a bipolar junction transistor.

38. The implantable medical device of claim 26, wherein the switch electrically coupled to the programmer detector and to the communication system further comprises:

a thyristor.

39. The implantable medical device of claim 26, wherein the switch electrically coupled to the programmer detector and to the communication system further comprises:

a triac.

40. The implantable medical device of claim 26, wherein the switch electrically coupled to the programmer detector and to the communication system further comprises:

a Reedswitch.

41. The implantable medical device of claim 26, wherein the switch electrically coupled to the programmer detector and to the communication system further comprises:

a junction field effect transistor.

42. An implantable medical device capable of interacting with at least one implantable lead positioned within a heart of a patient, the implantable medical device also capable of communicating with a programmer located in proximity to the implantable medical device, the implantable medical device comprising:

a power source;

programmer detector means for detecting a presence of the programmer in proximity to the implantable medical device;

communication means for communicating with the programmer;

inductive transreceiver coil means electrically coupled to the communication means for facilitating communication between the implantable medical device and the programmer; and

switching means electrically coupled to the. programmer detector means and to the communication means, the switching means electrically coupled in parallel with the inductive transreceiver coil means such that the switching means is opened in the presence of the programmer, thereby creating a communication path between the programmer and the communication means of the implantable medical device via the inductive transreceiver coil means.

43. The implantable medical device of claim 42, wherein the programmer detector means further comprises:

detection switch means which closes when the programmer detector means detects the presence of a programmer in proximity to the implantable medical device, thereby providing a signal to the switching means electrically coupled in parallel with the inductive transreceiver coil means which causes the switching means to open, producing an open circuit.

44. The implantable medical device of claim 42, wherein the communication means further comprises:

transreceiver means capable of transmitting information between the implantable medical device and the programmer via the inductive transreceiver coil means.

45. The implantable medical device of claim 42, wherein the inductive transreceiver coil means facilitates transmission of inductive signals between the implantable medical device and the programmer.

46. The implantable medical device of claim 42, wherein the inductive transreceiver coil means facilitates transmission of magnetically coupled signals between the implantable medical device and the programmer.

47. The implantable medical device of claim 42, wherein the inductive transreceiver coil means receives data signals from the programmer.

48. An implantable medical device capable of interacting with at least one implantable lead position within a heart of a patient, the implantable medical device also capable of communicating with a programmer located in proximity to the implantable medical device, the implantable medical device comprising:

a printed circuit board interconnecting several components including;

a programmer detector for detecting a presence of the programmer in proximity to the implantable medical device;

a communication system for communicating with the programmer;

a switch electrically coupled to the programmer detector and to the communication system, the switch opened in the presence of the programmer;

a control coupled to the switch for opening the switch;

a power source electrically coupled to the printed circuit board; and

an inductive transreceiver coil electrically coupled to the printed circuit board in parallel with the switch.

49. The implantable medical device of claim 48, and further comprising:

a frame surrounding the printed circuit board and the power source, wherein the inductive transreceiver coil resides within the frame.

50. The implantable medical device of claim 48, wherein the inductive transreceiver coil further comprises:

an aircoil.

51. The implantable medical device of claim 48, wherein the programmer detector further comprises:

a Reedswitch.

52. The implantable medical device of claim 48, wherein the programmer detector further comprises:

a Hall switch.

53. The implantable medical device of claim 48, wherein the switch further comprises:

a metal oxide semiconductor device.

54. The implantable medical device of claim 48, wherein the switch further comprises:

a Reedswitch.

55. The implantable medical device of claim 48, wherein the switch further comprises:

a bipolar junction transistor.

56. The implantable medical device of claim 48, wherein the switch further comprises:

a thyristor.

57. The implantable medical device of claim 48, wherein the switch further comprises:

a triac.

58. The implantable medical device of claim 48, wherein the switch further comprises:

a junction field effect transistor.