Methods and systems for management of atrial retrograde conduction and pacemaker mediated tachyarrhythmia threshold

• US 20080119902A1
• Filed: 11/17/2006
• Published: 05/22/2008
• Est. Priority Date: 11/17/2006
• Status: Active Grant

• Current Assignee: Cardiac Pacemakers Incorporated (Boston Scientific Corporation)
• Original Assignee: Cardiac Pacemakers Incorporated (Boston Scientific Corporation)
• Inventors: Bohn, Derek D., Garg, Ankur, Enrooth, Eric K.
• Granted Patent: US 7,801,610 B2
• Time in Patent Office: Days
• US Class Current: 607/14
• CPC Class Codes: A61N 1/3621 for treating or preventing abnormally high heart rate
• CPC Class Codes: A61N 1/371 Capture, i.e. successful stimulation
• CPC Class Codes: A61N 1/3712 Auto-capture, i.e. automatic adjustment of the stimulation threshold
• CPC Class Codes: A61N 1/3714 Atrial capture

Abstract

Methods and systems for classifying cardiac responses to pacing stimulation and managing retrograde conduction and pacemaker mediated tachyarrhythmia are described. An atrial pacing pulse and a ventricular pacing pulse are delivered during a paced cardiac cycle. A post ventricular atrial refractory period (PVARP) is timed following the ventricular pacing pulse. The system determines if the atrial pacing pulse captures the atrium. An atrial depolarization occurring after the paced cardiac cycle is sensed. Retrograde management is initiated if the atrial pacing pulse did not capture the atrium and the atrial depolarization occurred during the PVARP. Pacemaker mediated tachyarrhythmia (PMT) is initiated if the atrial pacing pulse did not capture the atrium and the atrial depolarization did not occur during the PVARP.

Claims

1. A method, comprising:

delivering an atrial pacing pulse and a ventricular pacing pulse during a paced cardiac cycle;

timing a post ventricular atrial refractory period (PVARP) following the ventricular pacing pulse;

determining if the atrial pacing pulse captures the atrium;

sensing an atrial depolarization occurring after the paced cardiac cycle;

initiating retrograde management if the atrial pacing pulse did not capture the atrium and the atrial depolarization occurred during the PVARP; and

initiating pacemaker mediated tachyarrhythmia (PMT) management if the atrial pacing pulse did not capture the atrium and the atrial depolarization did not occur during the PVARP.

2. The method of claim 1, wherein initiating the retrograde management comprises modifying pacing for at least one pacing cycle.

3. The method of claim 1, wherein initiating the retrograde management comprises delaying a next scheduled atrial pacing pulse following the paced cardiac cycle.

4. The method of claim 1, wherein initiating the retrograde management comprises delaying a next scheduled atrial pacing pulse if the next scheduled atrial pacing pulse is scheduled to occur when the atrial tissue is refractory.

5. The method of claim 4, wherein delaying the next scheduled atrial pacing pulse comprises delaying the next scheduled atrial pacing pulse until about 300 ms from the atrial depolarization.

6. The method of claim 1, wherein initiating the PMT management comprises extending a subsequent PVARP of at least one pacing cycle occurring after the paced cardiac cycle;

7. The method of claim 1, wherein initiating the PMT management comprises extending a subsequent PVARP of a next pacing cycle occurring after the paced cardiac cycle.

8. The method of claim 7, wherein extending the subsequent PVARP comprises extending the subsequent PVARP to about 500 ms.

9. The method of claim 1, wherein the atrial depolarization comprises a retrogradely conducted depolarization responsive to the ventricular pacing pulse.

10. The method of claim 1, wherein the atrial depolarization comprises a premature atrial contraction.

11. A cardiac rhythm management system, comprising:

a pulse generator configured to deliver an atrial pacing pulse and a ventricular pacing pulse via electrodes coupled to a heart during a paced cardiac cycle;

a post ventricular atrial refractory period (PVARP) timer configured to time a PVARP following the ventricular pacing pulse;

a capture detector configured to determine if the atrial pacing pulse captures the atrium;

a sensing system configured to sense an atrial depolarization that occurs after the paced cardiac cycle;

a retrograde management module configured to initiate retrograde management pacing if the atrial pacing pulse did not capture the atrium and the atrial depolarization occurred during the PVARP; and

a pacemaker mediated tachyarrhythmia (PMT) management module configured to initiate PMT management if the atrial pacing pulse did not capture the atrium and the atrial depolarization did not occur during the PVARP.

12. The system of claim 11, wherein the retrograde management module is configured to delay a next scheduled atrial pacing pulse following the paced cardiac cycle to initiate retrograde management.

13. The system of claim 11, wherein the retrograde management module is configured to delay a next scheduled atrial pacing pulse if the next scheduled atrial pacing pulse is scheduled to occur when the tissue is refractory.

14. The system of claim 13, wherein the retrograde management module is configured to delay the next schedule atrial pacing pulse until about 300 ms from the atrial depolarization.

15. The system of claim 11 wherein the PMT management module is configured to extend a subsequent PVARP of a next pacing cycle occurring after the paced cardiac cycle.

16. The system of claim 15, wherein extending the subsequent PVARP comprises extending the subsequent PVARP to about 500 ms.

17. The system of claim 11, wherein the atrial depolarization comprises a retrogradely conducted depolarization responsive to the ventricular pacing pulse.

18. The system of claim 11, wherein the atrial depolarization comprises a premature atrial contraction.

19. A cardiac rhythm management system, comprising:

a pulse generator configured to deliver an atrial pacing pulse and a ventricular pacing pulse via electrodes coupled to a heart during a paced cardiac cycle;

a post ventricular atrial refractory period (PVARP) timer configured to time a PVARP following the ventricular pacing pulse;

a capture detector configured to determine if the atrial pacing pulse captures the atrium;

a sensing system configured to senses an atrial depolarization that occurs after the paced cardiac cycle;

means for initiating retrograde management if the atrial pacing pulse did not capture the atrium and the atrial depolarization occurred during the PVARP; and

means for initiating pacemaker mediated tachyarrhythmia (PMT) management if the atrial pacing pulse did not capture the atrium and the atrial depolarization did not occur during the PVARP.

20. The system of claim 19, further comprising means for delaying a next scheduled atrial pacing pulse if the next scheduled atrial pacing pulse is scheduled to occur when the atrial tissue is refractory.

21. The system of claim 20, further comprising means for delaying the next scheduled atrial pacing pulse until about 300 ms from the atrial depolarization.

22. The system of claim 19, further comprising means for extending a subsequent PVARP of at least one pacing cycle occurring after the paced cardiac cycle;

23. The system of claim 19, further comprising means for extending a subsequent PVARP of a next pacing cycle occurring after the paced cardiac cycle.