Method and system for automatic anti-tachycardia pacing

• US 20030083703A1
• Filed: 10/25/2001
• Published: 05/01/2003
• Est. Priority Date: 10/25/2001
• Status: Active Grant

• Current Assignee: Cardiac Pacemakers Incorporated (Boston Scientific Corporation)
• Original Assignee: Cardiac Pacemakers Incorporated (Boston Scientific Corporation)
• Inventors: Girouard, Steven D., Zhu, Qingsheng, Hahn, Stephen John
• Granted Patent: US 6,775,572 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 1/3712 Auto-capture, i.e. automatic adjustment of the stimulation threshold

Abstract

A method and system for delivering anti-tachycardia pacing is disclosed. A cardiac rhythm management device, such as an implantable pacemaker having anti-tachycardia pacing capability, delivers anti-tachycardia pacing therapy in accordance with an anti-tachycardia pacing protocol upon detection of a terminable arrhythmia. The anti-tachycardia pacing is delivered as a burst of one or more pacing pulses at a specified coupling interval after a sensed ventricular polarization. By sensing if an evoked potential occurs, the device can determine whether or not the anti-tachycardia pacing burst has captured the ventricle and can adjust the coupling interval and/or other parameters accordingly.

Claims

1. A method for delivery of anti-tachycardia pacing (ATP) therapy by a cardiac rhythm management device, comprising:

generating sense signals representing electrical activity in a heart chamber and detecting a chamber sense when a sense signal exceeds a specified intrinsic detection threshold;

detecting a tachycardia in the heart chamber when a rate at which chamber senses are detected exceeds a specified tachycardia threshold value;

upon detection of a tachycardia, delivering a burst of one or more pacing pulses in accordance with an anti-tachycardia pacing protocol, where the burst is output after a specified coupling interval with respect to a chamber sense; and

,

determining if a pacing pulse has captured the heart chamber by detecting whether an evoked response occurs during a capture detection window following the output of a pacing pulse and storing an indication of whether capture has been achieved in a memory of the device.

2. The method of claim 1 wherein the heart chamber is a ventricle.

3. The method of claim 1 further comprising increasing the coupling interval when an initial pacing pulse of a burst has not captured the heart chamber.

4. The method of claim 1 further comprising decreasing the coupling interval when an initial pacing pulse of a burst has not captured the heart chamber.

5. The method of claim 1 further comprising delivering a burst with the coupling interval set to a specified minimum value and increasing the coupling interval when an initial pacing pulse of a burst has not captured the heart chamber.

6. The method of claim 1 wherein the delivered burst is a train of pacing pulses separated by a specified cycle length and further comprising terminating the burst when a pacing pulse fails to capture the heart chamber.

7. The method of claim 6 wherein the burst is a ramp-type burst such that the cycle length between pacing pulses is progressively shortened with each pulse in the burst.

8. The method of claim 1 wherein the delivered burst is a train of pacing pulses separated by a specified cycle length and further comprising adjusting the cycle length when a pacing pulse fails to capture the heart chamber.

9. The method of claim 8 wherein the cycle length is increased when a pacing pulse in a burst fails to capture the heart chamber.

10. The method of claim 8 wherein the cycle length is decreased when a pacing pulse in a burst fails to capture the heart chamber.

11. The method of claim 1 further comprising selecting an anti-tachycardia pacing protocol and recording the number of pacing pulses that failed to capture the heart chamber when a burst in accordance with the protocol is delivered.

12. The method of claim 11 further comprising selecting an anti-tachycardia pacing protocol with the fewest number of recorded capture failures.

13. A cardiac rhythm management device, comprising:

a sensing channel for generating sense signals representing electrical activity in a heart chamber;

a pacing channel for delivering paces to a selected heart chamber;

a controller for controlling the delivery of pacing pulses in accordance with a programmed mode, detecting a chamber sense when the sense signal exceeds a specified intrinsic detection threshold, and detecting an evoked response when the sense signal following a pace exceeds a specified evoked response detection threshold; and

,

wherein the controller is further programmed to;

detect a tachycardia in the heart chamber when a rate at which chamber senses are detected exceeds a specified tachycardia threshold value and deliver a burst of one or more pacing pulses to the heart chamber in accordance with an anti-tachycardia pacing protocol upon detection of a tachycardia, where the burst is output after a specified coupling interval with respect to a chamber sense; and

,

determine whether a pacing pulse has captured the heart chamber in accordance with whether an evoked response is detected during a capture detection window following the output of a pacing pulse.

14. The device of claim 13 wherein the controller is programmed to adjust the coupling interval if an initial pacing pulse of a burst has not captured the heart chamber.

15. The device of claim 14 wherein the controller is programmed to increase the coupling interval when an initial pacing pulse of a burst has not captured the heart chamber.

16. The device of claim 14 wherein the controller is programmed to decrease the coupling interval when an initial pacing pulse of a burst has not captured the heart chamber.

17. The device of claim 13 wherein the controller is programmed to deliver a burst with the coupling interval set to a specified minimum value and to increase the coupling interval when an initial pacing pulse of a burst has not captured the heart chamber.

18. The device of claim 13 wherein the delivered burst is a train of pacing pulses separated by a specified cycle length and wherein the controller is programmed to terminate the burst when a pacing pulse fails to capture the heart chamber.

19. The device of claim 17 wherein the burst is a ramp-type burst such that the cycle length between pacing pulses is progressively shortened with each pulse in the burst.

20. The device of claim 13 wherein the delivered burst is a train of pacing pulses separated by a specified cycle length and wherein the controller is programmed to adjust the cycle length when a pacing pulse fails to capture the heart chamber.

21. The device of claim 20 wherein the controller is programmed to increase the cycle length is when a pacing pulse in a burst fails to capture the heart chamber.

22. The device of claim 20 wherein the controller is programmed to decrease the cycle length is when a pacing pulse in a burst fails to capture the heart chamber.

23. The device of claim 13 wherein the controller is programmed to select an anti-tachycardia pacing protocol and record the number of pacing pulses that failed to capture the heart chamber when a burst in accordance with the protocol is delivered.

24. The device of claim 23 wherein the controller is programmed to select an anti-tachycardia pacing protocol with the fewest number of recorded capture failures.