Cardiac pacing system for prevention of ventricular fibrillation and ventricular tachycardia episode

• US 7,039,461 B1
• Filed: 05/13/2000
• Issued: 05/02/2006
• Est. Priority Date: 05/13/2000
• Status: Expired due to Fees

• Current Assignee: Cardiac Pacemakers Incorporated (Boston Scientific Corporation)
• Original Assignee: Cardiac Pacemakers Incorporated (Boston Scientific Corporation)
• Inventors: Lovett, Eric G.
• Primary Examiner(s): Bockelman, Mark
• Application Number:
  US09/569,295
• Time in Patent Office: 2,180 Days
• Field of Search: 607 25- 32, 607/54, 607 59- 61, 607/14, 600300-301, 600522-527
• 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 1/3956 Implantable devices for applying electric shocks to the heart, e.g. for cardioversion

Abstract

A cardiac pacing system preventing short-long-short pacing sequences. The system providing pacing pulses where necessary. The system having dynamic event window generation to adapt to changes in heart rate. The event window adaptable to process a number of intervals. The system including provisions for other inputs, such as sensor and morphology detection. The system adaptable for single mode and dual mode applications. The system also applicable to long pause prevention in atrial pacing and ventricular pacing.

Claims

1. A system, comprising:

a controller, connected to a sense and pulse delivery module, the controller receiving signals from one or more electrodes and providing pulse instructions for delivery of pulses to the one or more electrodes; and

an event window generator, connected to the controller, producing event windows for ventricular contraction events, the event windows each being a function of a plurality of intervals between ventricular contraction events and a ventricular rate trajectory,

wherein the controller produces an instruction for providing a ventricular contraction following an event from which one of the event windows begins if a ventricular contraction event is not detected during the one of the event windows.

2. The system of claim 1, wherein the event windows are decreased for increases in the ventricular rate trajectory.

3. The system of claim 2, wherein the event windows are increased for decreases in the ventricular rate trajectory.

4. The system of claim 1, wherein the ventricular contraction is produced from an atrial pace.

5. The system of claim 1, wherein the ventricular contraction is produced from a ventricular pace.

6. The system of claim 1, further comprising one or more sensors, connected to the controller.

7. The system of claim 6, further comprising a morphology detection system, connected to the controller, for detecting complexes indicative of cardiac arrhythmia.

8. The system of claim 7, wherein the event window is also a function of signals from the one or more sensors and/or signals from the morphology detection system.

9. The system of claim 8, wherein signals from the one or more sensors indicate conditions including one or more of physical exertion, elevated heart rate, circadian trends, and ultradian trends.

10. The system of claim 8, wherein, if the morphology detection system detects arrhythmia trigger complexes, the event window is decreased.

11. The system of claim 8, wherein, if the morphology detection system detects abnormal cardiac complexes, the event window is decreased.

12. The system of claim 1, wherein the event windows are each a function of an average of intervals of the plurality of intervals between ventricular contraction events.

13. The system of claim 12, wherein a number of the intervals of the plurality of intervals between ventricular contraction events is adjusted based on the standard deviation of a predetermined number of interval samples.

14. The system of claim 12, wherein the event windows are each calculated by a weighted average of the intervals of the plurality of intervals between ventricular contraction events.

15. The system of claim 14, wherein more recent intervals of the plurality of intervals between ventricular contraction events are weighted stronger than less recent intervals of the plurality of intervals between ventricular contraction events.

16. The system of claim 1, wherein the event windows are each calculated by interpolation from the plurality of intervals between ventricular contraction events.

17. The system of claim 1, wherein the event windows are each produced from a liner regression of the intervals of the plurality of intervals between ventricular contraction events.

18. The system of claim 1, further comprising a morphology detection system, connected to the controller, for detecting complexes indicative of cardiac arrhythmia.

19. The system of claim 18, wherein, if the morphology detection system detects arrhythmia trigger complexes, the event window is decreased.

20. The system of claim 18, wherein, if the morphology detection system detects abnormal cardiac complexes, the event window is decreased.