IMPLANTABLE MEDICAL DEVICE SENSING WIRELESS ECG AS SUBSTITUTE FOR INTRACARDIAC ELECTROGRAM

• US 20120330171A1
• Filed: 06/27/2012
• Published: 12/27/2012
• Est. Priority Date: 10/28/2004
• Status: Abandoned Application

• Current Assignee: Aaron Mccabe, David J. Yonce, Julie Thompson, Yi Zhang
• Original Assignee: Aaron Mccabe, David J. Yonce, Julie Thompson, Yi Zhang
• Inventors: Zhang, Yi, McCabe, Aaron, Yonce, David J., Thompson, Julie
• Application Number:
  US13/535,087
• Publication Number:
  US 20120330171A1
• Time in Patent Office: Days
• US Class Current: 600/509
• CPC Class Codes: A61B 5/287 Holders for multiple electrodes, e.g. electrode catheters for electrophysiological study [EPS]
• CPC Class Codes: A61B 5/349 Detecting specific parameters of the electrocardiograph cycle
• CPC Class Codes: A61B 5/353 Detecting P-waves
• CPC Class Codes: A61B 5/686 Permanently implanted devices, e.g. pacemakers, other stimulators, biochips A61B5/6861 takes precedence
• CPC Class Codes: A61N 1/3622 comprising two or more electrodes co-operating with different heart regions
• CPC Class Codes: A61N 1/3706 Pacemaker parameters stimulation threshold A61N1/371
• CPC Class Codes: A61N 1/3712 Auto-capture, i.e. automatic adjustment of the stimulation threshold
• CPC Class Codes: A61N 1/3756 Casings with electrodes thereon, e.g. leadless stimulators
• CPC Class Codes: A61N 1/3925 Monitoring; Protecting
• CPC Class Codes: A61N 1/3956 Implantable devices for applying electric shocks to the heart, e.g. for cardioversion

Abstract

A CRM system enhances intracardiac electrogram-based arrhythmia detection using a wireless electrocardiogram (ECG), which is a signal sensed with implantable electrodes and approximating a surface ECG. In one embodiment, the wireless ECG is sensed as a substitute signal for the intracardiac electrogram when the sensing of the intracardiac electrogram becomes unreliable.

Claims

1. A method, comprising:

sensing an intracardiac electrogram through an implantable lead;

detecting a failure signal indicating a failure in sensing the intracardiac electrogram; and

sensing a subcutaneous electrocardiogram (ECG) as a substitute for the intracardiac electrogram if the failure signal is detected.

2. The method of claim 1, wherein detecting the failure signal comprises detecting a signal indicative of a lead failure.

3. The method of claim 2, wherein detecting the signal indicative of the lead failure comprises:

sensing a lead impedance; and

producing the signal indicative of the lead failure using the lead impedance and a predetermined threshold.

4. The method of claim 1, wherein detecting the failure signal comprises detecting an external command transmitted to an implantable medical device from an external programmer.

5. The method of claim 1, further comprising:

producing a quality parameter indicative of a quality of the intracardiac electrogram; and

producing the failure signal when the quality parameter is below a predetermined threshold.

6. The method of claim 5, wherein producing the quality parameter comprises producing a signal-to-noise ratio.

7. The method of claim 1, wherein sensing the intracardiac electrogram comprises sensing the intracardiac electrogram using an implantable medical device, and sensing the subcutaneous ECG comprises sensing the subcutaneous ECG through a plurality of subcutaneous electrodes incorporated onto the implantable medical device.

8. The method of claim 7, wherein the implantable medical device comprises a hermetically sealed can housing a circuit of the implantable medical device and a header attached to the hermetically sealed can, and sensing the subcutaneous ECG comprises sensing the subcutaneous ECG through at least one header electrode of the plurality of subcutaneous electrodes, the at least one header electrode incorporated onto the header.

9. The method of claim 8, wherein sensing the subcutaneous ECG comprises sensing the subcutaneous ECG through the at least one header electrode and at least one can electrode of the plurality of subcutaneous electrodes, the at least one can electrode incorporated onto hermetically sealed can.

10. The method of claim 7, wherein the implantable medical device comprises a hermetically sealed can housing a circuit of the implantable medical device and a header attached to the hermetically sealed can, and sensing the subcutaneous ECG comprises sensing the subcutaneous ECG through one or more can electrodes of the plurality of subcutaneous electrodes, the one or more can electrodes incorporated onto the hermetically sealed can.

11. The method of claim 10, wherein sensing the subcutaneous ECG further comprises sensing the subcutaneous ECG through a can electrode of the plurality of subcutaneous electrodes including a conductive portion of the hermetically sealed can.

12. The method of claim 10, wherein sensing the subcutaneous ECG further comprises sensing the subcutaneous ECG through two or more concentric electrodes of the plurality of subcutaneous electrodes, the two or more concentric electrodes incorporated onto the hermetically sealed can.

13. The method of claim 7, wherein the implantable medical device comprises an antenna for telemetry, and sensing the subcutaneous ECG further comprises sensing the subcutaneous ECG through an antenna electrode of the plurality of subcutaneous electrodes, the antenna electrodes including a portion of the antenna.

14. An implantable medical device adapted to be coupled to an implantable lead and communicatively coupled to an external programmer, the implantable medical device comprising:

means sensing an intracardiac electrogram through the implantable lead;

means for detecting a failure signal indicating a failure in sensing the intracardiac electrogram; and

means for sensing a subcutaneous electrocardiogram (ECG) as a substitute for the intracardiac electrogram if the failure signal is detected.

15. The implantable medical device of claim 14, wherein the means for detecting the failure signal comprises means for detecting a signal indicative of a lead failure.

16. The implantable medical device of claim 15, wherein the means for detecting the signal indicative of the lead failure comprises:

means for sensing a lead impedance; and

means for producing the signal indicative of the lead failure using the lead impedance and a predetermined threshold.

17. The implantable medical device of claim 14, wherein the means for detecting the failure signal comprises means for detecting an external command transmitted from the external programmer.

18. The implantable medical device of claim 14, further comprising:

means for producing a quality parameter indicative of a quality of the intracardiac electrogram; and

means for producing the failure signal when the quality parameter is below a predetermined threshold.

19. The implantable medical device of claim 14, further comprising means for delivering pacing pulses.

20. The implantable medical device of claim 14, further comprising means for delivering cardioversion/defibrillation pulses.