Impingement detection for implantable medical devices

1. A system for at least one of delivering cardiac therapy or cardiac sensing, the system comprising:

an implantable medical device comprising:

a housing configured for implantation at least one of on or within a heart of a patient;

at least one fixation element configured to attach the housing to the heart; and

a sensor configured to produce a signal that indicates motion of the implantable medical device; and

processing circuitry configured to:

identify one or more impingements between the housing and another structure based on the signal from the sensor; and

provide an indication of the one or more impingements to a user.

2. The system of claim 1 , wherein the implantable medical device comprises:

a plurality of electrodes; and

signal generation circuitry within the housing, the signal generation circuitry configured to deliver cardiac pacing via the plurality of electrodes,

wherein the processing circuitry comprises processing circuitry of the implantable medical device within the housing configured to control the delivery of pacing by the signal generation circuitry.

3. The system of claim 2 , wherein the processing circuitry of the implantable medical device is configured to control the signal generation circuitry to deliver ventricular pacing via the plurality of electrodes.

4. The system of claim 2 , wherein the processing circuitry of the implantable medical device is configured to control the signal generation circuitry to deliver cardiac resynchronization therapy via the plurality of electrodes.

5. The system of claim 1 , wherein the housing is configured for implantation within the left ventricle of the heart.

6. The system of claim 1 , wherein the processing circuitry is configured to identify one or more collisions between the housing and the other structure based on the signal from the sensor.

7. The system of claim 1 , wherein the processing circuitry is configured to:

identify a heartbeat; and

identify one of the impingements during the heartbeat.

8. The system of claim 7 , wherein the processing circuitry is configured to:

identify a frequency of the signal during the heartbeat; and

identify the one of the impingements based on the frequency meeting one or more impingement criteria.

9. The system of claim 8 , wherein the frequency meeting the one or more impingement criteria includes a frequency component in the signal during systolic motion of the heartbeat exceeding a threshold value.

10. The system of claim 7 , wherein the processing circuitry is configured to:

identify motion in a direction other than a primary axis of motion during the heartbeat; and

identify the one of the impingements based on the motion in the direction other than the primary axis meeting one or more impingement criteria.

11. The system of claim 10 , wherein the primary axis of motion comprises a primary axis of systolic motion, and the motion in the direction other than the primary axis meeting the one or more impingement criteria includes an amount of the motion exceeding a threshold value.

12. The system of claim 1 , wherein the sensor comprises a three-dimensional accelerometer.

13. The system of claim 1 , wherein the other structure comprises a tissue of the heart.

14. A method for evaluating implantation of an implantable medical device configured for at least one of delivering cardiac therapy or cardiac sensing, wherein the implantable medical device is attached by a fixation element to a heart of a patient, the method comprising:

producing, by a sensor, a signal that is indicative of a motion of the implantable medical device; and

identifying one or more impingements between a housing of the implantable medical device and another structure based on the signal from the sensor.

15. The method of claim 14 , wherein the implantable medical device comprises a pacemaker configured to deliver cardiac pacing to the heart.

16. The method of claim 15 , wherein the implantable medical device is configured to deliver cardiac resynchronization therapy to at least one ventricle of the heart.

17. The method of claim 14 , wherein the implantable medical device is implanted within the heart.

18. The method of claim 14 , wherein identifying the one or more impingements comprises identifying, by processing circuitry of the implantable medical device, the one or more impingements based on the signal from the sensor.

19. The method of claim 14 , wherein identifying the one or more impingements comprises identifying one or more collisions between the housing and the other structure based on the signal from the sensor.

20. The method of claim 14 , wherein identifying the one or more impingements comprises:

identifying a heartbeat; and

identifying one of the impingements during the heartbeat.

21. The method of claim 20 , wherein identifying the one or more impingements comprises:

identifying a frequency of the signal during the heartbeat; and

identifying the one of the impingements based on the frequency meeting one or more impingement criteria.

22. The method of claim 21 , wherein the frequency meeting the one or more impingement criteria includes a frequency component in the signal during systolic motion of the heartbeat exceeding a threshold value.

23. The method of claim 20 , wherein identifying the one or more impingements comprises:

identifying motion in a direction other than a primary axis of motion during the heartbeat; and

identifying the one of the impingements based on the motion in the direction other than the primary axis meeting one or more impingement criteria.

24. The method of claim 23 , wherein the primary axis of motion comprises a primary axis of systolic motion, and the motion in the direction other than the primary axis meeting the one or more impingement criteria includes an amount of the motion exceeding a threshold value.

25. The method of claim 14 , wherein the sensor comprises a three-dimensional accelerometer.

26. The method of claim 14 , wherein identifying the one or more impingements comprises indicating to a user to reposition the implantable medical device.

27. The method of claim 26 , wherein repositioning the implantable medical device includes detaching the fixation element from the heart of the patient and attaching the implantable medical device at another location on the heart of the patient.

28. The method of claim 14 , wherein identifying the one or more impingements between the housing of the implantable medical device and the other structure comprises identifying one or more impingements between the housing and a cardiac tissue.

29. A system for evaluating implantation of an implantable medical device configured for at least one of delivering cardiac therapy or cardiac sensing, wherein the implantable medical device is attached by a fixation element to a heart of a patient, the system comprising:

means for producing, by a sensor, a signal that is indicative of a motion of the implantable medical device; and

means for identifying one or more impingements between a housing of the implantable medical device and another structure based on the signal from the sensor.

30. A non-transitory computer-readable storage medium comprising instructions that, when executed by processing circuitry of a medical device system for evaluating implantation of an implantable medical device configured for at least one of delivering cardiac therapy or cardiac sensing, wherein the implantable medical device is attached by a fixation element to a heart of a patient, cause the processing circuitry to:

produce, by a sensor, a signal that is indicative of a motion of the implantable medical device; and

identify one or more impingements between a housing of the implantable medical device and another structure based on the signal from the sensor.

31. A system for at least one of delivering cardiac therapy or cardiac sensing, the system comprising:

an implantable medical device comprising:

a housing configured for implantation at least one of on or within a heart of a patient;

at least one fixation element configured to attach the housing to the heart;

a sensor including a three-dimensional accelerometer, the sensor configured to produce a signal that indicates motion of the implantable medical device;

a plurality of electrodes; and

signal generation circuitry within the housing, the signal generation circuitry configured to deliver cardiac pacing via the plurality of electrodes; and

processing circuitry configured to:

identify a heartbeat;

identify one or more impingements between the housing and another structure based on the signal from the sensor;

identify one of the impingements during the heartbeat; and

provide an indication of the one of the impingements to a user,

wherein the processing circuitry comprises processing circuitry of the implantable medical device within the housing configured to control the delivery of pacing by the signal generation circuitry, and

wherein the housing is configured for implantation within the left ventricle of the heart.