Method and device for multi-chamber cardiac pacing in response to a tachycardia

• US 6,654,639 B1
• Filed: 05/07/2001
• Issued: 11/25/2003
• Est. Priority Date: 05/07/2001
• Status: Expired due to Term

• Current Assignee: Pacesetter Incorporated (Abbott Laboratories)
• Original Assignee: Pacesetter Incorporated (Abbott Laboratories)
• Inventors: Lu, Richard
• Primary Examiner(s): Evanisko, George R.
• Application Number:
  US09/850,560
• Time in Patent Office: 932 Days
• Field of Search: 607/4, 607/5, 607/9, 607/14
• US Class Current: 607/17
• CPC Class Codes: A61N 1/3622 comprising two or more electrodes co-operating with different heart regions
• CPC Class Codes: A61N 1/3684 for stimulating the heart at multiple sites of the ventricle or the atrium
• CPC Class Codes: A61N 1/36842 Multi-site stimulation in the same chamber

Abstract

An apparatus and method for performing multi-chamber anti-tachycardia pacing (ATP) in response to a tachycardia that is of particular use in an implantable cardiac stimulation device. The expected benefits of such a multi-chamber ATP include improved hemodynamic performance and the ability to terminate the tachycardia sooner. Embodiments of the present invention use an intrinsic chamber activation sequence and associated interchamber time delays, preferably automatically detected during a period of time when a pathologic tachycardia is not present, to treat a pathologic tachycardia should it occur. Such a device monitors two or more chambers of the patient'"'"'s heart, i.e., the controlled chambers, and in the event a tachycardia is detected, the device determines the chamber which originated the tachycardia. The device then calculates anti-tachycardia pacing (ATP) cycle lengths, typically as percentages of the detected tachycardia cycle length of the chamber where the tachycardia originated, and begins pacing the controlled chambers according to the intrinsic chamber activation sequence and interchamber delays (initially synchronized relative to a cardiac signal from the chamber which originated the tachycardia) at the ATP cycle lengths for a predefined period or until the tachycardia ends. Optionally, embodiments of the present invention may additionally include a hemodynamic sensor and may adaptively alter the activation sequence and/or interchamber time delays in response to feedback from the hemodynamic sensor.

Claims

1. An implantable cardiac stimulation device configured for controlling a plurality of chambers of a patient'"'"'s heart through a plurality of electrodes adapted to be implanted in a respective chamber of the heart, the stimulation device comprising:

pulse generating circuitry, coupled to the plurality of electrodes, configured to independently generate stimulation pulses to stimulate an associated heart chamber;

sensing circuitry, coupled to the plurality electrodes, configured to independently receive intrinsic cardiac signals from an associated heart chamber;

wherein the sensing circuit detects an intrinsic activation sequence and associated interchamber time delays;

a controller, coupled to the pulse generating circuitry and the sensing circuitry, configured to control the stimulation of each respective heart chamber, to detect the presence of tachycardia from the received intrinsic signals, and to determine which one of the chambers originated the tachycardia; and

wherein, in response to detecting tachycardia, the controller controls a sequence of stimulation pulses according to a predetermined anti-tachycardia pacing cycle length to the controlled chambers relative to the intrinsic chamber activation sequence and the associated interchamber time delays.

2. The implantable cardiac stimulation device of claim 1, wherein the controller controls the sequence of stimulation pulses by initially delivering the sequence of stimulation pulses relative to an intrinsic cardiac signal from the chamber which originated the tachycardia.

3. The implantable cardiac stimulation device of claim 1, wherein the cardiac stimulation device is further configured to control four chambers and wherein the controlled chambers comprise the patient'"'"'s right atrium, right ventricle, left atrium and left ventricle.

4. The implantable cardiac stimulation device of claim 1, wherein the controller is further configured to periodically determine the intrinsic chamber activation sequence and the associated time delays for the controlled chambers of the patient'"'"'s heart.

5. The implantable cardiac stimulation device of claim 4, wherein the controller is further configured to periodically determine the intrinsic chamber activation sequence and associated interchamber time delays during a time period without pathologic tachycardia.

6. The implantable cardiac stimulation device of claim 1, wherein:

the controller is further configured to determine the absence or presence of tachycardia by periodically determining an intrinsic cardiac cycle length for one or more cardiac cycles in each of the controlled chambers and comparing each intrinsic cardiac cycle length to a predetermined tachycardia threshold cycle length; and

the presence of tachycardia is indicated when the intrinsic cardiac cycle length is less than the predetermined tachycardia threshold cycle length and the absence of tachycardia is indicated when the intrinsic cardiac cycle length is greater than the predetermined tachycardia threshold cycle length.

7. The implantable cardiac stimulation device of claim 6, further comprising delivery time delays related to the associated interchamber time delays, wherein:

the controller, in response to detecting tachycardia, controls the sequence of stimulation pulses according to calculated anti-tachycardia pacing cycle lengths to the controlled chambers according to a delivery activation sequence related to the intrinsic chamber activation sequence and according to the delivery time delays.

8. The implantable cardiac stimulation device of claim 7, wherein the anti-tachycardia pacing cycle lengths is a percentage of the determined intrinsic cardiac cycle length.

9. The implantable cardiac stimulation device of claim 7, additionally comprising:

a hemodynamic sensor for monitoring the performance of the patient'"'"'s heart; and

wherein the controller is configured to adaptively alter the delivery activation sequence in response to changes in the monitored hemodynamic performance of the patient'"'"'s heart.

10. The implantable cardiac stimulation device of claim 7, additionally comprising:

a hemodynamic sensor for monitoring the performance of the patient'"'"'s heart; and

wherein

the controller is configured to adaptively alter the delivery time delays in response to changes in the monitored hemodynamic performance of the patient'"'"'s heart.

11. A method for stimulating a patient'"'"'s heart wherein the patient'"'"'s heart is comprised of a plurality of chambers capable of being controlled by an implantable stimulation device, the method comprising the steps of:

periodically determining an intrinsic chamber activation sequence and associated interchamber time delays for the controlled chambers of the patient'"'"'s heart;

detecting intrinsic cardiac signals from each of the controlled chambers;

determining the absence or presence of tachycardia in each of the controlled chambers in response to the intrinsic cardiac signals;

determining, in response to the presence of tachycardia, the chamber of the patient'"'"'s heart which originated the tachycardia; and

delivering, in response to the presence of tachycardia, a sequence of stimulation pulses to the controlled chambers of the patient'"'"'s heart according to the determined intrinsic chamber activation sequence and the associated interchamber time delay, wherein the stimulation pulses are delivered according to predetermined anti-tachycardia pacing cycle lengths.

12. The method of claim 11, wherein the periodically determining step comprises the steps of:

determining suitability for determining the intrinsic chamber activation sequence by periodically looking for the absence of a tachycardia in each of the controlled chambers; and

determining the intrinsic chamber activation sequence during a time period characterized by the absence of pathologic tachycardia in each of the controlled chambers.

13. The method of claim 11, wherein the step of determining the absence or presence of tachycardia comprises the steps of:

determining an intrinsic cardiac cycle length of at least one cardiac cycle for each of the controlled chambers;

comparing the intrinsic cardiac cycle length to a predetermined tachycardia threshold cycle length;

specifying the presence of tachycardia when it is determined that the intrinsic cardiac cycle length is less than the predetermined tachycardia threshold cycle length; and

specifying the absence of tachycardia when it is determined that the intrinsic cardiac cycle length is greater than the predetermined tachycardia threshold cycle length.

14. The method of claim 11, wherein the delivering step comprises the step of:

determining a calculated anti-tachycardia pacing cycle length based on at least one previous tachycardia cycles;

delivering, in response to the presence of tachycardia, a sequence of stimulation pulses to the controlled chambers of the patient'"'"'s heart according to the determined intrinsic chamber activation sequence and according to delivery time delays related to the determined interchamber time delays, wherein;

the sequence of stimulation pulses are delivered according to the calculated anti-tachycardia pacing cycle length; and

the sequence of stimulation pulses is initially delivered relative to an intrinsic cardiac signal from the chamber which originated the tachycardia.

15. The method of claim 14, additionally comprising the steps of:

(a) monitoring hemodynamic performance of the patient'"'"'s heart;

(b) adjusting one of the delivery time delays;

(c) continuing to deliver stimulation pulses using a further adjusted delivery time delay in the same direction as a previously adjusted delivery time delay if the delivery of stimulation pulses using the previously adjusted delivery time delay increases the hemodynamic performance of the patient'"'"'s heart; and

(d) delivering stimulation pulses according to the delivery time delay used before performing step (b) if the delivery of stimulation pulses according to the previously adjusted delivery time delay decreases the hemodynamic performance of the patient'"'"'s heart.

16. The method of claim 14, additionally comprising the step of:

determining the delivery time delays by generating delivery time delay values relative to the determined interchamber time delays scaled according to the anti-tachycardia pacing cycle length.

17. The method of claim 16, additionally comprising the steps of:

(a) monitoring hemodynamic performance of the patient'"'"'s heart;

(b) adjusting one of the delivery time delays;

(c) continuing to deliver stimulation pulses using a further adjusted delivery time delay in the same direction if the delivery of stimulation pulses using the previously adjusted delivery time delay increases the hemodynamic performance of the patient'"'"'s heart; and

(d) delivering stimulation pulses according to the delivery time delay used before performing step (b) if the delivery of stimulation pulses according to the previously adjusted delivery time delay decreases the hemodynamic performance of the patient'"'"'s heart.

18. The method of claim 11, additionally comprising the steps of:

determining an intrinsic cardiac cycle length for each of the controlled chambers; and

setting the anti-tachycardia pacing cycle lengths to percentages of the determined intrinsic cardiac cycle length for the chamber which originated the tachycardia.

19. The method of claim 11, wherein the delivering stimulation pulses step additionally comprising the steps of:

(a) monitoring hemodynamic performance of the patients heart;

(b) delivering stimulation pulses to the patient'"'"'s heart according to a modified activation sequence wherein at least two chambers of the patient'"'"'s heart are stimulated in an order opposite to that in the determined intrinsic chamber activation sequence;

(c) continuing to deliver stimulation pulses using the modified activation sequence if the delivery of stimulation pulses according to the modified activation sequence increases the hemodynamic performance of the patient'"'"'s heart; and

(d) delivering stimulation pulses according to the activation sequence used before performing step (b) if the delivery of stimulation pulses according to the modified activation sequence decreases the hemodynamic performance of the patient'"'"'s heart.

20. The method of claim 19, additionally comprising the steps of:

(e) monitoring hemodynamic performance of the patient'"'"'s heart;

(f) adjusting one of the delivery time delays;

(g) continuing to deliver stimulation pulses using a further adjusted delivery time delay in the same direction if the delivery of stimulation pulses using the previously adjusted delivery time delay increases the hemodynamic performance of the patient'"'"'s heart; and

(h) delivering stimulation pulses according to the delivery time delay used before performing step (f) if the delivery of stimulation pulses according to the previously adjusted delivery time delay decreases the hemodynamic performance of the patient'"'"'s heart.

21. An implantable cardiac stimulation device configured for controlling a plurality of chambers of a patient'"'"'s heart through a plurality of electrodes implanted in electrical contact with each of the controlled chambers, the stimulation device comprising:

means for delivering a stimulation pulse to each of the controlled chambers of the patient'"'"'s heart;

means for receiving intrinsic cardiac signals from each controlled cardiac chamber;

wherein the means for receiving intrinsic cardiac signals detects an intrinsic activation sequence and associated interchamber time delays

means for determining the presence of tachycardia from the intrinsic cardiac signals;

means for determining anti-tachycardia pacing cycle lengths in response to the presence of tachycardia;

means for determining which chamber originated the tachycardia; and

means for delivering a sequence of stimulation pulses according to a calculated anti-tachycardia pacing cycle length to each of the controlled chambers relative to the intrinsic chamber activation sequence and the associated interchamber time delays, wherein the sequence of stimulation pulses are delivered in response to the presence of tachycardia and the sequence of stimulation pulses is initially delivered relative to an intrinsic cardiac signal of the chamber which originated the tachycardia.

22. The implantable cardiac stimulation device of claim 21, further comprising:

means to periodically determine the intrinsic chamber activation sequence and associated interchamber time delays for the controlled chambers of the patient'"'"'s heart.

23. The implantable cardiac stimulation deliver of claim 21, additionally comprising:

means for monitoring the hemodynamic performance of the patient'"'"'s heart;

means to adaptively alter a delivery activation sequence used for stimulating the controlled chambers of the patient'"'"'s heart in response to changes in the monitored hemodynamic performance of the patient'"'"'s heart; and

means for determining the delivery activation sequence based on the intrinsic chamber activation sequence.

24. The implantable cardiac stimulation deliver of claim 21, additionally comprising:

means for monitoring the hemodynamic performance of the patient'"'"'s heart;

means to adaptively alter a delivery interchamber delay used for controlling a time delay between stimulating two of the controlled chambers of the patient'"'"'s heart in response to changes in the monitored hemodynamic performance of the patient'"'"'s heart; and

means for determining the delivery interchamber delay based on one of the intrinsic interchamber delays.