IMD STABILITY MONITOR

• US 20130079861A1
• Filed: 09/25/2012
• Published: 03/28/2013
• Est. Priority Date: 09/27/2011
• Status: Active Grant

• Current Assignee: Medtronic Incorporated (Medtronic Plc)
• Original Assignee: Medtronic Incorporated (Medtronic Plc)
• Inventors: Reinert, Michael A., Williams, Eric R., Sheldon, Todd J.
• Granted Patent: US 9,101,281 B2
• Time in Patent Office: Days
• US Class Current: 607/126
• CPC Class Codes: A61B 2560/0276 Determining malfunction
• CPC Class Codes: A61B 2560/0468 Built-in electrodes
• CPC Class Codes: A61B 5/0031 Implanted circuitry
• CPC Class Codes: A61B 5/0538 invasively, e.g. using a catheter
• CPC Class Codes: A61B 5/11 Measuring movement of the entire body or parts thereof, e.g. head or hand tremor, mobility of a limb for measuring pulse A61B5/02 ;A61B5/1038 takes precedence; motion detection to correct for motion artifacts in physiological signals A61B5/721
• CPC Class Codes: A61B 5/276 Protection against electrode failure
• CPC Class Codes: A61B 5/287 Holders for multiple electrodes, e.g. electrode catheters for electrophysiological study [EPS]
• CPC Class Codes: A61B 5/686 Permanently implanted devices, e.g. pacemakers, other stimulators, biochips A61B5/6861 takes precedence
• CPC Class Codes: A61B 5/6869 Heart
• CPC Class Codes: A61B 5/6882 Anchoring means
• CPC Class Codes: A61B 5/6883 Sutures
• CPC Class Codes: A61N 1/0597 Surface area electrodes, e.g. cardiac harness
• CPC Class Codes: A61N 1/36542 controlled by body motion, e.g. acceleration
• CPC Class Codes: A61N 1/371 Capture, i.e. successful stimulation
• CPC Class Codes: A61N 1/3756 Casings with electrodes thereon, e.g. leadless stimulators

Abstract

Techniques for determining an attachment stability of leadless pacing device (LPD) implanted within a patient are described. For example, the LPD may detect one or more stability metrics from one or more electrodes of the LPD and/or an activity sensor within the LPD. Based on one or more of these stability metrics, e.g., a mechanical motion of the LPD, a stability module within the LPD may determine the attachment stability of the LPD within the patient. If the attachment stability is insufficient to provide efficacious therapy or indicates at least partial dislodgement of the LPD from tissue, the LPD may wirelessly transmit stability information to an external device. In some examples, the LPD may be implanted within a chamber of the heart.

Claims

1. A method comprising:

detecting one or more stability metrics with a leadless pacing device implanted within a patient; and

determining an attachment stability of the leadless pacing device based on the one or more stability metrics.

2. The method of claim 1, wherein determining the attachment stability comprises identifying at least one of an insufficient electrode/tissue interface for efficacious pacing therapy or an at least partial mechanical dislodgement of the leadless pacing device from patient tissue.

3. The method of claim 1, wherein the one or more stability metrics comprise at least one of an electrode impedance, a capture threshold, a cardiac waveform morphology, one or more cardiac events, a pacing threshold, oversensing, or a mechanical motion of the leadless pacing device.

4. The method of claim 1, wherein determining the attachment stability comprises comparing each of the one or more stability metrics to a respective specific metric threshold.

5. The method of claim 1, wherein determining the attachment stability comprises comparing two of the one or more stability metrics to each other.

6. The method of claim 5, further comprising:

comparing a mechanical motion of the leadless pacing device to one or more cardiac events; and

determining the attachment stability to indicate at least partial mechanical dislodgement of the leadless pacing device from patient tissue when the mechanical motion does not correlate to the one or more cardiac events.

7. The method of claim 1, wherein the one or more stability metrics comprise a primary stability metric and a secondary stability metric, and wherein determining the attachment stability comprises:

detecting the primary stability metric;

determining that the primary stability metric exceeds a respective specific metric threshold;

in response to the determination, detecting the secondary stability metric; and

comparing the secondary stability metric to the respective specific metric threshold.

8. The method of claim 1, further comprising:

generating stability information based on at least one of the one or more stability metrics and the attachment stability; and

wirelessly transmitting stability information from the leadless pacing device to an external device.

9. The method of claim 8, further comprising automatically generating a stability notification and transmitting the stability notification to a clinician when the stability information indicates that at least one of pacing therapy is ineffective or the leadless pacing device is at risk for complete detachment from patient tissue.

10. The method of claim 1, wherein detecting one or more stability metrics with the leadless pacing device implanted within the patient comprises detecting one or more stability metrics with the leadless pacing device implanted completely within a heart of the patient.

11. A leadless pacing device comprising:

two or more electrodes;

a stability module configured to detect one or more stability metrics and determine an attachment stability of the device based on the one or more stability metrics; and

a housing that encloses the stability module, wherein the two or more electrodes are disposed on the outside of the housing.

12. The device of claim 11, wherein the stability module is configured to, based on the one or more stability metrics, identify at least one of an insufficient electrode/tissue interface for efficacious pacing therapy or an at least partial mechanical dislodgement of the device from patient tissue.

13. The device of claim 11, wherein the one or more stability metrics comprise at least one of an electrode impedance measured from one of the two or more leadless electrodes, a capture threshold of one of the two or more leadless electrodes, a cardiac waveform morphology generated from the two or more leadless electrodes, one or more cardiac events, a pacing threshold, oversensing, and a mechanical motion of the leadless pacing device.

14. The device of claim 11, wherein the stability module is configured to at least one of compare each of the one or more stability metrics to a respective specific metric threshold and compare two of the one or more stability metrics to each other.

15. The device of claim 14, wherein the stability module is configured to compare a mechanical motion of the leadless pacing device to one or more cardiac events and determine the attachment stability to indicate at least partial mechanical dislodgement of the device from patient tissue when the mechanical motion does not correlate to the one or more cardiac events.

16. The device of claim 11, further comprising an activity sensor configured to detect a mechanical motion of the device, wherein the activity sensor is contained within the housing.

17. The device of claim 11, further comprising a telemetry module configured to wirelessly transmit stability information to an external device, wherein the stability information is based on at least one of the one or more stability metrics and the attachment stability.

18. A leadless pacing device comprising:

means for detecting one or more stability metrics with a leadless pacing device implanted within a patient; and

means for determining an attachment stability of the leadless pacing device based on the one or more stability metrics.

19. The leadless pacing device of claim 18, wherein the means for determining the attachment stability comprises means for identifying at least one of an insufficient electrode/tissue interface for efficacious pacing therapy and an at least partial mechanical dislodgement of the leadless pacing device from patient tissue.

20. The leadless pacing device of claim 18, further comprising means for detecting a mechanical motion of the leadless pacing device within the patient.

21. The leadless pacing device of claim 18, further comprising:

means for generating stability information based on at least one of the one or more stability metrics and the attachment stability; and

means for wirelessly transmitting stability information from the leadless pacing device to an external device.