Systems and Methods for Ranking and Selection of Pacing Vectors

• US 20110004264A1
• Filed: 06/24/2010
• Published: 01/06/2011
• Est. Priority Date: 07/02/2009
• Status: Active Grant

• Current Assignee: Cardiac Pacemakers Incorporated (Boston Scientific Corporation)
• Original Assignee: Cardiac Pacemakers Incorporated (Boston Scientific Corporation)
• Inventors: Shome, Shibaji, Ding, Jiang, Siejko, Krzysztof Z.
• Granted Patent: US 8,886,313 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 1/36185 Selection of the electrode configuration
• CPC Class Codes: A61N 1/36514 controlled by a physiological quantity other than heart potential, e.g. blood pressure controlled by two or more physical parameters A61N1/36585
• CPC Class Codes: A61N 1/36542 controlled by body motion, e.g. acceleration
• CPC Class Codes: A61N 1/36585 controlled by two or more physical parameters
• CPC Class Codes: A61N 1/368 comprising more than one electrode co-operating with different heart regions A61N1/3622, A61N1/3627 take precedence
• CPC Class Codes: A61N 1/3686 configured for selecting the electrode configuration on a lead A61N1/3688 takes precedence
• CPC Class Codes: A61N 1/3704 Circuits specially adapted therefor, e.g. for sensitivity control
• CPC Class Codes: A61N 1/371 Capture, i.e. successful stimulation

Abstract

Approaches to rank potential left ventricular (LV) pacing vectors are described. Early elimination tests are performed to determine the viability of LV cathode electrodes. Some LV cathodes are eliminated from further testing based on the early elimination tests. LV cathodes identified as viable cathodes are tested further. Viable LV cathode electrodes are tested for hemodynamic efficacy. Cardiac capture and phrenic nerve activation thresholds are then measured for potential LV pacing vectors comprising a viable LV cathode electrode and an anode electrode. The potential LV pacing vectors are ranked based on one or more of the hemodynamic efficacy of the LV cathodes, the cardiac capture thresholds, and the phrenic nerve activation thresholds.

Claims

1. A method of operating a cardiac device to rank potential cardiac pacing vectors, comprising:

measuring one or more parameter values indicative of pacing viability for a plurality of cathode electrodes of a cardiac chamber;

identifying, based on the measured parameter values, a set of the cathode electrodes as viable cathodes for the cardiac chamber and subject to further testing and eliminating at least some of the cathode electrodes from further testing;

after identifying the viable cathode electrodes for the cardiac chamber;

measuring a value of a parameter indicating hemodynamic function of pacing for at least some of the viable cathode electrodes; and

measuring one or both of a cardiac capture threshold and a phrenic nerve activation threshold for potential pacing vectors of the cardiac chamber, each potential LV pacing vector defined between a viable cathode electrode and an anode electrode;

ranking the potential LV pacing vectors based on the measured hemodynamic function value and the one or more measured thresholds; and

generating an output of the cardiac device indicating the ranking.

2. The method of claim 1, wherein ranking the potential pacing vectors comprises ranking potential LV pacing vectors in a first tier and one or more additional tiers, at least one tier ranking viable LV cathode electrodes based on the measured value of the hemodynamic function parameter and at least another tier ranking the potential LV pacing vectors based on a difference between the cardiac capture threshold and the phrenic nerve activation threshold.

3. The method of claim 1, wherein measuring the parameter values indicative of pacing viability comprises measuring one or more of an intrinsic signal amplitude and a pacing impedance.

4. The method of claim 1, wherein measuring the parameter values indicative of pacing viability comprises measuring whether cardiac capture is achieved over a limited number of pacing energies.

5. The method of claim 1, wherein measuring the values of the hemodynamic function parameter comprises measuring a cardiac electrical signal propagation delay.

6. The method of claim 5, wherein:

the viable cathode electrodes comprise viable cathode electrodes for the left ventricle; and

measuring the propagation delay comprises measuring the propagation delay between a right chamber event and detection of a left ventricular depolarization responsive to the right chamber event at the viable left ventricular cathode electrode.

7. The method of claim 1, further comprising extrapolating a parameter value, interpolating a parameter value, or not measuring a parameter value for at least some viable cathode electrodes based on their proximity to other cathode electrodes.

8. The method of claim 1, further comprising:

identifying a set of hemodynamically preferred cathode electrodes based on the measured value of the hemodynamic function parameter;

delivering pacing to the using at least some of the viable cathode electrodes;

monitoring for phrenic nerve activation caused by the pacing; and

eliminating from further consideration each cathode electrode that is associated with phrenic nerve activation and which is not included in the set of hemodynamically preferred of cathode electrodes.

9. The method of claim 1, further comprising measuring one or both of a signal amplitude and a pacing impedance for each of the potential pacing vectors, wherein ranking the potential pacing vectors further comprises ranking the potential pacing vectors based on one or both of the signal amplitude and the pacing impedance.

10. The method of claim 1, further comprising eliminating from further testing potential pacing vectors which are undesirable or not commonly used, wherein the eliminating is based on one or both of survey information and data mining.

11. The method of claim 1, further comprising:

monitoring one or more of the potential pacing vectors for anodal stimulation;

storing anodal stimulation information associated with the one or more potential pacing vectors together with ranking information.

12. The method of claim 1, further comprising automatically changing from a first pacing vector used to deliver pacing to a second pacing vector used to deliver pacing based on the ranking.

13. The method of claim 1, further comprising eliminating a potential pacing vector from further testing based on a proximity of an electrode of the potential pacing vector to an infarct site.

14. A cardiac device for ranking potential pacing vectors for a patient, comprising:

a plurality of cardiac electrodes electrically coupled to a heart, the plurality of electrodes disposed on one or more implantable leads;

a cathode viability module configured to measure one or more parameter values for a plurality of cathode electrodes of a cardiac chamber and, based on the measured parameter values, to identify for further testing a set of viable cathode electrodes for the cardiac chamber and to eliminate from the further testing one or more non-viable cathode electrodes;

a hemodynamic function module configured to measure a parameter value indicative of hemodynamic function for at least some of the viable cathode electrodes;

a threshold test module configured to measure one or both of a cardiac capture threshold and a phrenic nerve activation threshold for potential pacing vectors of the cardiac chamber, each potential pacing vector defined between a viable cathode electrode and an anode electrode;

a ranking module configured to rank at least some of the potential pacing vectors based on the value of the hemodynamic function parameter and one or more of the measured capture threshold and the phrenic nerve activation threshold and to provide an output based on the ranking.

15. The cardiac device of claim 14, wherein the ranking module is configured to identify one or more electrodes that are within an infarct region based on the signal amplitudes and the capture thresholds of the identified electrodes and to eliminate from the ranking potential pacing vectors that use the one or more electrodes near the infarct region.

16. The cardiac device of claim 14, wherein the cathode viability module, the hemodynamic function module, the threshold test module and the ranking module are disposed outside of the patient'"'"'s body in a patient-external pacing system analyzer that is coupled to the implantable cardiac leads.

17. The cardiac device of claim 16, wherein the medical device comprises an accelerometer configured to be attached to an external portion of the patient'"'"'s body and to sense movement indicative of phrenic nerve activation.

18. The cardiac device of claim 16, wherein the medical device comprises subcutaneous electrode disposed on a lead that simulates a can electrode of a cardiac rhythm management devices.

19. The cardiac device of claim 14 the cathode viability module, the hemodynamic efficacy module, the threshold test module and the ranking module are disposed within the housing of an implantable cardiac device.

20. The cardiac device of claim 14, further comprising a user interface configured to receive an input from a user, wherein ranking the potential pacing vectors is based at least in part on the user input.

21. The cardiac device of claim 20, wherein:

the user interface is configured to display one or both of text and graphics identifying the potential pacing vectors in an order that is based on the ranking and to receive an input from a user indicating a priority for parameters used to rank the potential pacing vectors; and

the ranking module is configured to re-rank the potential pacing vectors based on the ranking priority.

22. A cardiac medical system, comprising, comprising:

a plurality of implantable pacing electrodes configured to deliver pacing pulses to a heart and to sense cardiac electrical signals;

test circuitry configured to measure intrinsic signal amplitudes and cardiac capture thresholds of the pacing electrodes;

ranking circuitry configured to identify one or more electrodes as proximate to an infarct region based on the intrinsic signal amplitudes and the cardiac capture thresholds and to eliminate as potential pacing electrodes the one or more electrodes identified as proximate to an infarct site; and

pacing circuitry configured to deliver pacing pulses to the heart via using an electrode other than the one or more electrodes identified as proximate to an infarct site.

23. The system of claim 22, wherein the ranking circuitry is configured to identify the one or more electrodes proximate to an infarct region as those electrodes having higher capture threshold values when compared with capture threshold values of other electrodes, wherein the electrodes identified as proximate to the infarct region and the other electrodes have substantially similar intrinsic signal amplitudes.