Subcutaneous cardiac rhythm management with asystole prevention therapy

1. A system, comprising:

detection circuitry;

energy delivery circuitry capable of delivering a plurality of cardiac therapies comprising at least a tachycardia therapy, a bradycardia therapy, and an asystole prevention therapy;

therapy instructions stored in the energy delivery circuitry, the therapy instructions executable to direct delivery of the plurality of cardiac therapies;

one or more electrodes configured for subcutaneous, non-intrathoracic placement in a patient and for coupling to the detection circuitry and energy delivery circuitry;

detection circuitry configured to receive cardiac signals using the one or more electrodes and detect a tachycardia condition, a bradycardia condition, and an asystole condition using the cardiac signals;

a controller coupled to the detection circuitry and energy delivery circuitry, the controller, in response to a cardiac condition requiring treatment, executing at least some of the therapy instructions to coordinate delivery of a selected one of the tachycardia, bradycardia, and asystole prevention therapies, the asystole prevention therapy being delivered at a rate below that of the bradycardia therapy and at 20 pulses per minute or less upon detection of the asystole condition;

a patient-external communications device configured to receive data relating to the selected one of the tachycardia, bradycardia, and asystole prevention therapies, wherein the patient-external communications device facilitates communication with a network or server system; and

a display coupled to the patient-external communications device for displaying the received data.

2. The system of claim 1 , wherein the plurality of cardiac therapies comprises a bradycardia pacing therapy.

3. The system of claim 1 , wherein the plurality of cardiac therapies comprises a cardiac resynchronization therapy.

4. The system of claim 1 , wherein the plurality of cardiac therapies comprises an antitachycardia pacing therapy.

5. The system of claim 1 , wherein the plurality of cardiac therapies comprises a defibrillation therapy.

6. The system of claim 1 , wherein the plurality of cardiac therapies comprises a rate smoothing pacing therapy.

7. The system of claim 1 , wherein the plurality of cardiac therapies comprises a sub-threshold stimulation therapy.

8. The system of claim 1 , wherein the one or more electrodes are configured for cardiac pacing and sensing.

9. The system of claim 1 , further comprising a housing within which the detection circuitry, energy delivery circuitry, and controller are situated, wherein the housing is configured for patient-external placement.

10. The system of claim 9 , wherein the housing comprises one or more electrodes coupled to the detection circuitry and energy delivery circuitry.

11. The system of claim 9 , further comprising one or more surface electrodes configured for coupling to the detection circuitry and energy delivery circuitry.

12. The system of claim 9 , further comprising a coupling arrangement configured to couple and de-couple the one or more electrodes to and from the detection circuitry and energy delivery circuitry.

13. The system of claim 1 , further comprising a housing within which at least one of the detection circuitry, energy delivery circuitry, and controller is situated, wherein the housing is configured for implantation in a patient.

14. The system of claim 13 , wherein the one or more electrodes comprises at least one electrode disposed in or on the housing.

15. The system of claim 1 , wherein the asystole prevention therapy comprises delivery of no more than ten pacing pulses.

16. The system of claim 1 , wherein the asystole prevention therapy comprises delivery of pacing pulses at a rate insufficient to restore full patient consciousness.

17. The system of claim 1 , wherein the rate below that of the bradycardia therapy is a fixed rate or a variable rate.

18. The system of claim 1 , further comprising a housing within which the detection circuitry, energy delivery circuitry, and controller are situated, wherein the housing is configured for implantation in a patient and the one or more electrodes are disposed in or on the housing to define a unitary structure.

19. The system of claim 18 , wherein the housing is configured to have an arcuate shape.

20. A system, comprising:

a housing configured for subcutaneous, non-intrathoracic placement relative to a patient;

energy delivery circuitry provided in the housing and capable of delivering each of a tachycardia therapy, a bradycardia therapy, and an asystole prevention therapy;

therapy instructions stored in the energy delivery circuitry, the therapy instructions executable to direct delivery of the tachycardia therapy, the bradycardia therapy, and the asystole prevention therapy, the asystole prevention therapy comprising a pacing rate lower than that associated with the bradycardia therapy and 20 pulses per minute or less;

one or more electrodes configured for subcutaneous, non-intrathoracic placement and coupled to the detection circuitry and energy delivery circuitry;

detection circuitry provided in the housing and configured to receive cardiac signals using the one or more electrodes and to detect a tachycardia condition, a bradycardia condition, and an asystole condition using the cardiac signals;

a controller provided in the housing and coupled to the detection circuitry and energy delivery circuitry, the controller, in response to a cardiac condition requiring treatment, executing at least some of the therapy instructions to direct delivery of a selected one of the tachycardia, bradycardia, and asystole prevention therapies in response to detection of a corresponding one of the tachycardia condition, the bradycardia condition, and the asystole condition, respectively;

a patient-external communications device configured to receive data relating to the selected one of the tachycardia, bradycardia, and asystole prevention therapies, wherein the patient-external communications device facilitates communication with a network or server system; and

a display coupled to the patient-external communications device for displaying the received data.

21. The system of claim 20 , wherein the bradycardia therapy comprises a bradycardia pacing therapy.

22. The system of claim 20 , wherein the therapy instructions are executable to direct delivery of a cardiac resynchronization therapy.

23. The system of claim 20 , wherein the therapy instructions are executable to direct delivery of an antitachycardia pacing therapy.

24. The system of claim 20 , wherein the therapy instructions are executable to direct delivery of a defibrillation therapy.

25. The system of claim 20 , wherein the therapy instructions are executable to direct delivery of a rate smoothing pacing therapy.

26. The system of claim 20 , wherein the therapy instructions are executable to direct delivery of a sub-threshold stimulation therapy.

27. The system of claim 20 , wherein the one or more electrodes are configured for cardiac pacing and sensing.

28. The system of claim 20 , wherein the one or more electrodes comprises at least one electrode disposed in or on the housing.

29. The system of claim 20 , wherein the asystole prevention therapy delivered by the energy delivery circuitry comprises delivery of pacing pulses at a rate insufficient to restore full patient consciousness.

30. The system of claim 20 , wherein the asystole prevention therapy delivered by the energy delivery circuitry comprises delivery of no more than ten pacing pulses.

31. The system of claim 30 , wherein the rate lower than the pacing rate is a fixed rate or a variable rate.

32. The system of claim 20 , wherein the one or more electrodes are disposed in or on the housing to define a unitary structure.

33. The system of claim 32 , wherein the housing is configured to have an arcuate shape.

34. The system of claim 20 , wherein the one or more electrodes comprise at least one subcutaneous, non-intrathoracic electrode array.

35. The system of claim 34 , wherein the at least one subcutaneous, non-intrathoracic electrode array is coupled to the housing via a lead.

36. A method, comprising:

sensing cardiac activity from a subcutaneous, non-intrathoracic location of a patient;

detecting one of a plurality of cardiac conditions, each cardiac condition necessitating treatment in response to the sensed cardiac activity, the plurality of cardiac conditions comprising a tachycardia condition, a bradycardia condition, and an asystole condition;

delivering, in response to detecting a corresponding one of the plurality of cardiac conditions, one of a plurality of available cardiac therapies to treat the detected corresponding cardiac condition, the plurality of cardiac therapies comprising at least a tachycardia therapy, a bradycardia therapy, and an asystole prevention therapy, the asystole prevention therapy comprising a pacing rate lower than that associated with the bradycardia therapy and 20 pulses per minute or less;

transmitting data relating to the delivered one of the tachycardia, bradycardia, and asystole prevention therapies to a patient-external communications device, wherein the patient-external communications device facilitates communication with a network or server system; and

displaying the data transmitted to the patient-external communications device.

37. The method of claim 36 , wherein the plurality of cardiac therapies comprises a bradycardia pacing therapy.

38. The method of claim 36 , wherein the plurality of cardiac therapies comprises a cardiac resynchronization pacing therapy.

39. The method of claim 36 , wherein the plurality of cardiac therapies comprises an antitachycardia pacing therapy.

40. The method of claim 36 , wherein the plurality of cardiac therapies comprises a defibrillation therapy.

41. The method of claim 36 , wherein the plurality of cardiac therapies comprises a rate smoothing pacing therapy.

42. The method of claim 36 , wherein the plurality of cardiac therapies comprises a sub-threshold stimulation therapy.

43. The method of claim 36 , wherein detecting comprises detecting the one of the plurality of cardiac conditions at a subcutaneous, non-intrathoracic location.

44. The method of claim 36 , wherein detecting comprises detecting the cardiac condition at a patient-external location.

45. The method of claim 36 , wherein energy for the plurality of cardiac therapies is provided from a patient-external source.

46. The method of claim 36 , wherein energy for the plurality of cardiac therapies is provided from a subcutaneous, non-intrathoracic source.

47. The method of claim 36 , wherein delivering the plurality of cardiac therapies comprises delivering monophasic waveforms.

48. The method of claim 36 , wherein delivering the plurality of cardiac therapies comprises delivering multiphasic waveforms.

49. A system, comprising:

means for sensing cardiac activity from a subcutaneous, non-intrathoracic location of a patient;

means for detecting one of a plurality of cardiac conditions, each cardiac condition necessitating treatment in response to the sensed cardiac activity, the plurality of cardiac conditions comprising a tachycardia condition, a bradycardia condition, and an asystole condition;

means for delivering, in response to detecting a corresponding one of the plurality of cardiac conditions, one of a plurality of cardiac therapies to treat the detected corresponding cardiac condition, the plurality of cardiac therapies comprising at least a tachycardia therapy, a bradycardia therapy, and an asystole prevention therapy, all of which can be delivered by the system, the asystole prevention therapy comprising a pacing rate lower than that associated with the bradycardia therapy and 20 pulses per minute or less;

means for transmitting data relating to the delivered one of the tachycardia, bradycardia, and asystole prevention therapies to a patient-external communications device, wherein the patient-external communications device facilitates communication with a network or server system; and

means for displaying the data transmitted to the patient-external communications device.

50. The system of claim 49 , wherein the plurality of cardiac therapies comprises a bradycardia pacing therapy.

51. The system of claim 49 , wherein the plurality of cardiac therapies comprises a cardiac resynchronization pacing therapy.

52. The system of claim 49 , wherein the plurality of cardiac therapies comprises an antitachycardia pacing therapy.

53. The system of claim 49 , wherein the plurality of cardiac therapies comprises a defibrillation therapy.

54. The system of claim 49 , wherein the plurality of cardiac therapies comprises a rate smoothing pacing therapy.

55. The system of claim 49 , wherein the plurality of cardiac therapies comprises a sub-threshold stimulation therapy.

56. The system of claim 49 , wherein the detecting means comprises means for detecting the one of the plurality of cardiac conditions at a subcutaneous, non-intrathoracic location.

57. The system of claim 49 , wherein the detecting means comprises means for detecting the cardiac condition at a patient-external location.

58. The system of claim 49 , further comprising means for supplying energy for the plurality of cardiac therapies from a patient-external source.

59. The system of claim 49 , further comprising means for supplying energy for the plurality of cardiac therapies from a subcutaneous, non-intrathoracic source.

60. The system of claim 49 , wherein the delivering means comprises means for delivering monophasic waveforms.

61. The system of claim 49 , wherein the delivering means comprises means for delivering multiphasic waveforms.