PACING METHOD

• US 20090276000A1
• Filed: 05/05/2009
• Published: 11/05/2009
• Est. Priority Date: 09/30/2002
• Status: Active Grant

• Current Assignee: Medtronic Incorporated (Medtronic Plc)
• Original Assignee: Medtronic Incorporated (Medtronic Plc)
• Inventors: Laske, Timothy G., Iaizzo, Paul A.
• Granted Patent: US 8,332,035 B2
• Time in Patent Office: Days
• US Class Current: 607/28
• CPC Class Codes: A61N 1/056 Transvascular endocardial electrode systems
• CPC Class Codes: A61N 1/0573 chacterised by means penetrating the heart tissue, e.g. helix needle or hook

Abstract

A method for delivering physiological pacing includes selecting an electrode implant site for sensing cardiac signals, which is in proximity to the heart'"'"'s intrinsic conduction system, where pacing stimulation results in a rhythm breaking out at an intrinsic location, and selected in response to a ratio of sensed P-wave amplitude to sensed R-wave amplitude.

Claims

1. A method, comprising:

inserting at least one electrode into cardiac tissue in proximity to a portion of an intrinsic conduction system of a patient'"'"'s heart;

measuring, using the at least one electrode, a P-wave amplitude and an R-wave amplitude;

determining a ratio of the P-wave amplitude to the R-wave amplitude;

selecting an electrode implant site for sensing cardiac signals in response to the ratio of the P-wave amplitude to the R-wave amplitude;

positioning an electrode at the selected electrode implant site for sensing; and

sensing a cardiac signal using the electrode positioned at the selected electrode implant site.

2. The method of claim 1, further comprising:

inserting the at least one electrode at various points in proximity to the portion of the intrinsic conduction system; and

determining the ratio of the P-wave amplitude to the R-wave amplitude for each of the various points.

3. The method of claim 2 wherein inserting the at least one electrode at various points comprises varying an insertion depth of the at least one electrode.

4. The method of claim 3 wherein the at least one electrode comprises an extendable and retractable electrode and wherein varying an insertion depth comprises advancing the extendable and retractable electrode to various depths within the cardiac tissue.

5. The method of claim 2 wherein inserting the at least one electrode at various points comprises changing an insertion site of the at least one electrode.

6. The method of claim 1, wherein inserting the at least one electrode comprises inserting a plurality of electrodes in proximity to a portion of the intrinsic conduction system, the method further comprising:

measuring a P-wave amplitude and an R-wave amplitude for each of the plurality of electrodes; and

determining a ratio of the P-wave amplitude to the R-wave amplitude for each of the plurality of the electrodes.

7. The method of claim 1 further comprising:

measuring a pacing threshold using the at least one electrode when pacing stimulation results in a rhythm breaking out in the intrinsic conduction system;

selecting an electrode implant site for pacing in response to the measured pacing threshold;

positioning an electrode at the selected electrode implant site for pacing; and

delivering physiological pacing using the electrode positioned at the selected electrode implant site for pacing.

8. The method of claim 7 wherein the selected electrode implant site for sensing and the selected electrode implant site for pacing are the same electrode implant site;

the electrode implant site selected in response to the P-wave to R-wave amplitude determined for the electrode implant site exceeding a predetermined ratio threshold and the pacing threshold measured for the electrode implant site being no greater than a predetermined pacing threshold.

9. The method of claim 8 wherein the predetermined ratio threshold being approximately 0.5 and the predetermined pacing threshold being approximately 1.5 volts.

10. The method of claim 1 wherein inserting the at least one electrode comprises advancing the at least one electrode endocardially into cardiac tissue.

11. The method of claim 1 wherein inserting the at least on electrode comprises advancing the at least one electrode epicardially into cardiac tissue.

12. A method, comprising:

inserting an electrode pair into cardiac tissue in proximity to a portion of an intrinsic conduction system of a patient'"'"'s heart;

positioning the electrode pair at various points in proximity to the portion of the intrinsic conduction system;

measuring, using the electrode pair, a P-wave amplitude and an R-wave amplitude at each of the various points;

determining a ratio of the P-wave amplitude to the R-wave amplitude;

selecting an electrode implant site for sensing cardiac signals in response to the ratio of the P-wave amplitude to the R-wave amplitude;

positioning the electrode pair at the selected electrode implant site for sensing; and

sensing a cardiac signal using the electrode pair positioned at the selected electrode implant site.

13. The method of claim 12 wherein positioning the electrode pair at various points comprises varying an insertion depth of the electrode pair.

14. The method of claim 12 wherein inserting the electrode pair at various points comprises changing an insertion site of the electrode pair.

15. The method of claim 12, wherein inserting the electrode pair comprises inserting an array of electrodes in proximity to a portion of the intrinsic conduction system, the method further comprising:

measuring a P-wave amplitude and an R-wave amplitude for electrode pairs selected from the array of electrodes; and

determining a ratio of the P-wave amplitude to the R-wave amplitude for each of the electrode pairs.

16. The method of claim 12 further comprising:

measuring a pacing threshold using at least one electrode out of the electrode pair when pacing stimulation results in a rhythm breaking out in the intrinsic conduction system;

selecting an electrode implant site for pacing in response to the measured pacing threshold;

positioning an electrode at the selected electrode implant site for pacing; and

delivering physiological pacing using the electrode positioned at the selected electrode implant site for pacing.

17. The method of claim 16 wherein the selected electrode implant site for sensing and the selected electrode implant site for pacing are the same electrode implant site,

the electrode implant site being selected in response to the P-wave to R-wave ratio determined for the electrode implant site exceeding a predetermined ratio threshold and the pacing threshold measured for the electrode implant site being no greater than a predetermined pacing threshold.

18. The method of claim 17 wherein the predetermined ratio threshold being approximately 0.5 and the predetermined pacing threshold being approximately 1.5 volts.

19. The method of claim 12 wherein inserting the electrode pair comprises advancing the electrode pair endocardially into cardiac tissue.

20. The method of claim 12 wherein inserting the electrode pair comprises advancing the electrode pair epicardially into cardiac tissue.