Systems and methods for leadless pacing and shock therapy

1. A method of coordinating operation of a subcutaneous implantable cardioverter defibrillator (SICD) and a pacing device (PD) implanted within a heart of a patient using one-way communication from the SICD to the PD, the method comprising:

determining, by the SICD and based on a detected tachyarrhythmia, to deliver anti-tachyarrhythmia therapy to the patient to treat the detected tachyarrhythmia;

transmitting, by the SICD, a communication from the SICD to the PD requesting the PD deliver anti-tachyarrhythmia therapy to the patient in accordance with a communication protocol;

determining, by the SICD and without direct communication from PD to the SICD in accordance with the communication protocol, that the PD did not deliver anti-tachyarrhythmia therapy; and

adjusting, by the SICD and based on the determination that the PD did not deliver anti-tachyarrhythmia therapy, at least one of a tachyarrhythmia detection criteria and a therapy parameter of the SICD.

2. The method of claim 1 , further comprising determining, by the PD, not to deliver anti-tachyarrhythmia therapy, wherein the tachyarrhythmia therapy comprises anti-tachycardia pacing.

3. The method of claim 1 , wherein determining by the SICD to deliver anti-tachyarrhythmia therapy comprises determining to deliver anti-tachycardia pacing.

4. The method of claim 1 , wherein determining by the SICD to deliver anti-tachyarrhythmia therapy comprises determining to deliver high voltage shock therapy.

5. The method of claim 1 , further comprising:

receiving, by the PD, the communication from the SICD requesting the PD deliver anti-tachyarrhythmia therapy to the patient; and

in the absence of a determination by the PD not to deliver anti-tachyarrhythmia therapy, delivering, by the PD, anti-tachyarrhythmia therapy as requested by the SICD.

6. The method of claim 1 , wherein adjusting, by the SICD and based on the determination that the PD did not deliver anti-tachyarrhythmia therapy, comprises adjusting a detection parameter and further comprising:

subsequently determining, by the SICD and based on a tachyarrhythmia detected using the adjusted detection parameter to deliver anti-tachyarrhythmia therapy to the patient.

7. The method of claim 1 , further comprising:

detecting, by SICD and without direct communication from PD to the SICD in accordance with the communication protocol, the delivery of anti-tachyarrhythmia therapy by the PD;

transmitting, by the SICD to the PD, a communication identifying that the delivered anti-tachyarrhythmia therapy has not captured a rhythm of the heart; and

determining, by the PD, at least one updated parameter value that at least partially defines additional anti-tachyarrhythmia therapy.

8. The method of claim 7 , further comprising:

subsequent to delivering anti-tachyarrhythmia therapy that has not captured a rhythm of the heart, delivering, by the PD, anti-tachyarrhythmia therapy defined at least partially by the determined updated parameter value.

9. The method of claim 1 , further comprising, subsequent to determining, by the SICD, to deliver anti-tachyarrhythmia therapy:

entering, by the SICD, an anti-tachycardia pacing detection mode;

while operating in the anti-tachycardia pacing detection mode, filtering anti-tachyarrhythmia pacing signals from the sensed signals on one or more detection channels of a sensing module of the SICD.

10. The method of claim 1 , further comprising, subsequent to determining, by the SICD, to deliver anti-tachyarrhythmia therapy:

entering, by the SICD, an anti-tachycardia pacing detection mode;

while operating in the anti-tachycardia pacing detection mode, implementing an algorithm that discriminates between intrinsic beats and pacing pulses.

11. The method of claim 1 , wherein adjusting at least one of a tachyarrhythmia detection criteria and a therapy parameter comprises adjusting, by the SICD and based on the determination that the PD did not deliver anti-tachyarrhythmia therapy, one or more tachyarrhythmia detection rules to reduce sensitivity to detecting tachyarrhythmias.

12. The method of claim 1 , further comprising sending, by the SICD and based on the determination that the PD did not deliver anti-tachycardia pacing, a second communication in accordance with the communication protocol, wherein the SICD sends the second communication using at least one of a different communication vector and a higher power.

13. An implantable cardioverter defibrillator (ICD) comprising:

one or more electrodes configured to be implanted external to a heart of a patient;

a housing configured to be implanted in a patient external to a ribcage of the patient;

a communication module configured to transmit communication messages in accordance with a communication protocol to a pacing device (PD) implanted within a heart of the patient;

a sensing module configured to sense an electrical signal from the heart of the patient via the one or more electrodes; and

a processor configured to:

detect a tachyarrhythmia within the electrical signal sensed by the sensing module;

determine, based on the detected tachyarrhythmia, to deliver anti-tachyarrhythmia therapy to the patient to treat the detected tachyarrhythmia;

transmit, via the communication module and based on the determination to delivery anti-tachyarrhythmia therapy, a communication message to the PD requesting the PD to deliver anti-tachycardia pacing to the heart of the patient;

determine, without direct communication from PD to the SICD in accordance with the communication protocol, whether the PD delivered anti-tachycardia pacing; and

adjusting, based on the determination of whether the PD delivered anti-tachycardia pacing, operation of the ICD.

14. The ICD of claim 13 , wherein the processor determines that the PD did not deliver anti-tachycardia pacing and adjusts operation of the ICD by adjusting a therapy parameter.

15. The ICD of claim 14 , wherein the processor adjusts the therapy parameter by terminating charging and ceasing delivery of the anti-tachyarrhythmia therapy.

16. The ICD of claim 13 , wherein the processor determines that the PD did not deliver anti-tachycardia pacing and adjusts operation of the ICD by adjusting a tachyarrhythmia detection criteria to reduce sensitivity to detecting tachyarrhythmias.

17. The ICD of claim 13 , wherein the processor determines that the PD did not deliver anti-tachycardia pacing and adjusts operation of the ICD by adjusting a tachyarrhythmia detection parameter and subsequently determines, based on a tachyarrhythmia detected using the adjusted detection parameter, to deliver anti-tachyarrhythmia therapy to the patient.

18. The ICD of claim 13 , wherein the processor determines that the PD delivered anti-tachycardia pacing and adjusts operation of the ICD by filtering the anti-tachyarrhythmia pacing signals from the electrical signals sensed on one or more detection channels of the sensing module.

19. The ICD of claim 13 , wherein the processor determines that the PD delivered anti-tachycardia pacing and adjusts operation of the ICD by implementing an algorithm that discriminates between intrinsic beats and pacing pulses.

20. A method of coordinating operation of a subcutaneous implantable cardioverter defibrillator (SICD) and a pacing device (PD) implanted within a heart of a patient using one-way communication from the SICD to the PD, the method comprising:

determining, by the SICD and based on a detected tachyarrhythmia, to deliver anti-tachyarrhythmia therapy to the patient to treat the detected tachyarrhythmia;

sending, by the SICD, a first communication in accordance with a communication protocol requesting the PD delivery anti-tachycardia pacing;

receiving, by the PD, the first communication from the SICD requesting the PD deliver anti-tachycardia pacing to the heart of the patient;

determining, by the PD, not to deliver anti-tachycardia pacing to the patient;

determining, by the SICD and without direct communication from PD to the SICD in accordance with the communication protocol, that the PD did not anti-tachycardia pacing; and

sending, by the SICD and based on the determination that the PD did not deliver anti-tachycardia pacing, a second communication in accordance with the communication protocol, wherein the second communication is sent using at least one of a different communication vector and a higher power signal.