PACE DISCRIMINATION OF TACHYCARDIA USING ATRIAL-VENTRICULAR PACING

• US 20110077703A1
• Filed: 09/30/2009
• Published: 03/31/2011
• Est. Priority Date: 09/30/2009
• Status: Active Grant

• Current Assignee: Medtronic Incorporated (Medtronic Plc)
• Original Assignee: Medtronic Incorporated (Medtronic Plc)
• Inventors: Gilberg, Jeffrey M., Jackson, Troy Edward, Brown, Mark L.
• Granted Patent: US 8,718,762 B2
• Time in Patent Office: Days
• US Class Current: 607/14
• CPC Class Codes: A61N 1/3622 comprising two or more electrodes co-operating with different heart regions
• CPC Class Codes: A61N 1/3716 with reduction of residual polarisation effects
• CPC Class Codes: A61N 1/39622 Pacing therapy

Abstract

A cardiac medical device and associated method control delivery of dual chamber burst pacing pulses in response to detecting tachycardia. In one embodiment, a single chamber pacing pulse is delivered in response to detecting a tachycardia. Dual chamber pacing pulses are delivered subsequent to the single chamber pacing pulse. An intrinsic depolarization is sensed subsequent to delivering the dual chamber pacing pulses. The tachycardia episode is classified in response to the sensed intrinsic depolarization.

Claims

1. A method for discriminating tachycardia for use in a cardiac medical device capable of sensing cardiac signals and delivering cardiac therapies, the method comprising;

sensing cardiac signals and detecting a tachycardia episode in response to the sensed cardiac signals;

delivering a plurality of dual chamber pacing pulses in response to detecting the tachycardia episode;

applying a tachycardia discrimination blanking interval subsequent to delivering the plurality of dual chamber pacing pulses;

sensing at least one intrinsic event subsequent to the blanking interval; and

classifying the detected tachycardia episode as one of ventricular tachycardia and supraventricular tachycardia in response to the at least one sensed intrinsic event.

2. The method of claim 1, further comprising setting the blanking interval approximately equal to a cycle length of the tachycardia episode.

3. The method of claim 1, further comprising setting the blanking interval a predetermined amount less than a cycle length of the tachycardia episode.

4. The method of claim 1 further comprising:

determining whether an earliest occurring event sensed subsequent to the plurality of dual chamber pacing pulses occurs during the blanking interval;

wherein classifying the tachycardia episode when an earliest occurring event occurs during the blanking interval comprises

identifying a plurality of sensed intrinsic events subsequent to the blanking interval,

identifying an event pattern using the plurality of sensed intrinsic events, and

classifying the tachycardia episode in response to the identified event pattern.

5. The method of claim 3 wherein identifying the pattern comprises identifying two consecutive events sensed in a first chamber without an intervening event sensed in a second chamber between the two consecutive events,

wherein classifying the tachycardia episode comprises classifying the episode as originating in the first chamber.

6. The method of claim 3 wherein identifying the event pattern further comprises using the earliest occurring sensed event.

7. The method of claim 3 wherein identifying the event pattern comprises identifying a 1:

1 correspondence between events sensed in a first heart chamber and events sensed in a second heart chamber;

comparing a morphology of a sensed event to a known morphology in response to identifying the 1;

1 correspondence; and

classifying the tachycardia episode in response to the morphology comparison.

8. The method of claim 1 further comprising:

determining a time interval between an earliest occurring event sensed in a first heart chamber subsequent to the blanking interval and a next event occurring in a second heart chamber;

comparing the time interval to a threshold; and

classifying the tachycardia episode in response to the comparison.

9. The method of claim 8 wherein classifying the tachycardia further comprises comparing a morphology of a sensed event to a known morphology episode in response to the threshold comparison.

10. A cardiac medical device for delivering anti-tachycardia pacing, comprising:

a plurality of electrodes implantable within a patient for sensing cardiac signals and delivering cardiac pacing pulses;

a therapy delivery module coupled to the plurality of electrodes for delivering pacing pulses to the patient'"'"'s heart via the plurality of electrodes; and

a controller coupled to the therapy delivery module and adapted to be electrically connected to the plurality of electrodes, the controller configured to;

detect a tachycardia episode from the cardiac signals,

control the therapy delivery module to deliver, via the plurality of electrodes, a plurality of dual chamber pacing pulses in response to the detected tachycardia episode;

apply a tachycardia discrimination blanking interval subsequent to delivering the plurality of dual chamber pacing pulses;

identify at least one intrinsic event sensed subsequent to the blanking interval; and

classify the detected tachycardia episode as one of ventricular tachycardia and supraventricular tachycardia in response to the at least one sensed intrinsic event.

11. The device of claim 10, wherein the controller is further configured to set the blanking interval approximately equal to a cycle length of the tachycardia episode.

12. The device of claim 10, wherein the controller is further configured to set the blanking interval a predetermined amount less than a cycle length of the tachycardia episode.

13. The device of claim 10 wherein the controller is further configured to:

determine whether an earliest occurring event sensed subsequent to the plurality of dual chamber pacing pulses occurs during the blanking interval;

identify a plurality of sensed intrinsic events subsequent to the blanking interval in response to the earliest occurring event occurring during the blanking interval,

identify an event pattern using the plurality of sensed intrinsic events, and

classify the tachycardia episode in response to the identified event pattern.

14. The device of claim 13 wherein the controller is further configured to identify two consecutive events sensed in a first chamber without an intervening event sensed in a second chamber between the two consecutive event, and classify the tachycardia episode as originating in the first chamber in response to identifying the two consecutive events.

15. The device of claim 13 wherein the controller is further configured to identify the event pattern using the earliest occurring sensed event.

16. The device of claim 13 wherein the controller is further configured to identifying a 1:

1 correspondence between events sensed in a first heart chamber and events sensed in a second heart chamber,

compare a morphology of a sensed event to a known morphology in response to identifying the 1;

1 correspondence, and

classify the tachycardia episode in response to the morphology comparison.

17. The device of claim 10 wherein the controller is further configured to:

determine a time interval between an earliest occurring event sensed in a first heart chamber subsequent to the blanking interval and a next event occurring in a second heart chamber;

compare the time interval to a threshold; and

classifying the tachycardia episode in response to the comparison.

18. The device of claim 17 wherein the controller is further configured to compare a morphology of the at least one sensed intrinsic event to a known morphology in response to the threshold comparison;

and

classify the tachycardia episode in response to the morphology comparison.

19. A computer-readable medium programmed with instructions for delivering anti-tachycardia pacing, the medium comprising instructions for causing a programmable processor to:

sense cardiac signals and detect a tachycardia episode in response to the sensed cardiac signals;

deliver a plurality of dual chamber pacing pulses in response to detecting the tachycardia episode;

apply a tachycardia discrimination blanking interval subsequent to delivering the plurality of dual chamber pacing pulses;

sense at least one intrinsic event subsequent to the blanking interval; and

classify the detected tachycardia episode as one of ventricular tachycardia and supraventricular tachycardia in response to the at least one sensed intrinsic event.