Method for including redundancy in communicating an alert condition from an implanted system to an external system

1. A method in an implanted medical system configured to communicate an alert signal to an external system, the method comprising:

detecting an occurrence of an event;

generating, by an alert signaling unit, the alert signal based on the occurrence of the event:

monitoring, by an internal controller of the implanted medical system, a first wireless communication system configured to transmit the alert signal; and

responsive to determining, by the internal controller, that the first wireless communication system is in fault condition, transmitting the alert signal from the implanted medical system to the external system via a transcutaneous energy transfer system (TETS).

2. The method of claim 1 , further comprising attempting to transmit the alert signal to the external system via the first wireless communication system while transmitting the alert signal via the TETS.

3. The method of claim 1 , wherein the fault condition includes a failure of a responder of the external system to respond to one of the alert signal and a test signal.

4. The method of claim 1 , wherein the alert signal transmitted via the TETS is included in a power control signal, the power control signal having one of a request for increased power and a request for decreased power.

5. The method of claim 1 , further comprising, producing, by the external system and based on the alert signal, a system replacement indicator.

6. An implanted medical device configured to communicate an alert signal to an external system, the implanted medical device including circuitry configured to:

detect an occurrence of an event;

generate, by an alert signaling unit, the alert signal based on the occurrence of the event

monitor a first wireless communication system configured to transmit the alert signal; and

responsive to determining that the first wireless communication system is in fault condition, transmit the alert signal from the implanted medical device to the external system via a transcutaneous energy transfer system (TETS).

7. The implanted medical device of claim 6 , wherein the circuitry is further configured to attempt to transmit the alert signal to the external device via the first wireless communication system while transmitting the alert signal via the TETS.

8. The implanted medical device of claim 6 , wherein the fault condition includes a failure of a responder of the external system to respond to one of the alert signal and a test signal.

9. The implanted medical device of claim 6 , wherein the alert signal transmitted via the TETS is included in a power control signal, the power control signal having one of a request for increased power and a request for decreased power.

10. A method in an external system in communication with an implanted medical device via a transcutaneous energy transfer system (TETS), the method comprising:

receiving a first signal via a first wireless communication system;

experiencing, by a responder of the external system, a fault condition, wherein the fault condition comprises a failure of the responder to respond to the first signal;

receiving a second signal via the TETS; and

decoding the second signal to determine a presence or absence of an alert signal.

11. The method of claim 10 , further comprising transmitting via the TETS to the implanted medical device a response signal responsive to the determination of the presence of the alert signal.

12. The method of claim 10 , further comprising sending a fault signal to the implanted medical device when a signal from the implanted medical device sent on a first wireless link cannot be decoded.

13. The method of claim 10 , further comprising transmitting to the implanted medical device a signal that triggers the implanted medical device to transmit the alert signal to the external system via a selected one of the TETS and the first wireless communication system.

14. An external system configured to communicate with an implanted medical device via a transcutaneous energy transfer system (TETS), the external system including circuitry configured to:

receive a first signal via a first wireless communication system;

experience a fault condition, wherein the fault condition comprises a failure to respond to the first signal;

receive a second signal via the TETS; and

decode the second signal to determine a presence or absence of an alert signal.

15. The external system of claim 14 , wherein the circuitry is further configured to transmit via the TETS to the implanted medical device a response signal responsive to the determination of the presence of the alert signal.

16. The external system of claim 14 , wherein the circuitry is further configured to transmit a fault signal to the implanted medical device when a signal from the implanted medical device sent on a first wireless link cannot be decoded.

17. The external system of claim 14 , wherein the circuitry is further configured to transmit to the implanted medical device a signal that triggers the implanted medical device to transmit the alert signal to the external system via a selected one of the TETS and the first wireless communication system.

18. The external system of claim 14 , wherein the circuitry is further configured to, responsive to determining the presence of the alert signal, produce a system replacement indicator based on the alert signal.