CARDIAC PACING SYSTEM FOR PREVENTION OF VENTRICULAR FIBRILLATION AND VENTRICULAR TACHYCARDIA EPISODE

• US 20100249866A1
• Filed: 06/15/2010
• Published: 09/30/2010
• Est. Priority Date: 05/13/2000
• Status: Active Grant

• Current Assignee: Eric G. Lovett
• Original Assignee: Eric G. Lovett
• Inventors: Lovett, Eric G.
• Granted Patent: US 8,239,021 B2
• Time in Patent Office: Days
• 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 1/3956 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;

an event window generator, connected to the controller, producing event windows for ventricular contraction events;

one or more sensors connected to the controller; and

a morphology detection system, connected to the controller, for detecting abnormal complexes,

wherein the event windows are a function of ventricular rate and ventricular rate trajectory over a plurality of intervals between ventricular contraction events, signals from the one or more sensors, and information from the morphology detection system.

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

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

4. The system of claim 1, wherein the signals from the one or more sensors comprise signals indicative of one or more of physical exertion, elevated heart rate, circadian trends, and ultradian trends.

5. The system of claim 1, wherein the information from the morphology detection system comprises information on detection of arrhythmia trigger complexes.

6. The system of claim 5, wherein the event windows are decreased in response to the arrhythmia trigger complexes being detected.

7. The system of claim 1, wherein the information from the morphology detection system comprises information on detection of abnormal cardiac complexes.

8. The system of claim 7, wherein the event windows are decreased in response to the abnormal cardiac complexes being detected.

9. 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;

one or more sensors, connected to the controller;

a morphology detection system, connected to the controller, for detecting complexes indicative of cardiac arrhythmia; 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 one or more of signals from the one or more sensors and signals from the morphology detection system,

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.

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

11. The system of claim 9, wherein, if the morphology detection system detects arrhythmia trigger complexes, the event window is decreased.

12. The system of claim 9, wherein, if the morphology detection system detects abnormal cardiac complexes, the event window is decreased.

13. The system of claim 9, wherein the event windows are each a function of a plurality of intervals between ventricular contraction events, a ventricular rate trajectory over the plurality of intervals between ventricular contraction events, and one or more of signals from the one or more sensors and signals from the morphology detection system,

14. The system of claim 13, wherein the event windows are decreased for increases in the ventricular rate trajectory.

15. The system of claim 13, wherein the event windows are increased for decreases in the ventricular rate trajectory.

20. The method of claim 15, comprising:

monitoring one or more sensors for one or more conditions associated with onset of cardiac arrhythmia; and

if the one or more conditions are detected from the sensors, decreasing the event window for increased sensitivity to long pauses between ventricular contractions.

16. A method, comprising:

monitoring a plurality of ventricular contraction events including a last ventricular contraction event;

determining a plurality of intervals between the plurality of ventricular contraction events;

generating one or more time derivatives using the plurality of intervals;

generating an event window using the plurality of intervals and at least one of the one or more time derivatives, the event window beginning from the last ventricular contraction event;

monitoring for a current ventricular contraction event during the event window; and

if a current ventricular contraction event is not detected during the event window, providing an instruction to a pulse generating device to produce a ventricular contraction.

17. The method of claim 16, wherein the event window is produced by an equation:

event window=(average over N intervals)−

C*d(heart rate)/dT,

where C is a constant, N is an integer, and d(heart rate)/dT is a ventricular rate trajectory being one of the one or more time derivatives generated using the plurality of intervals.

18. The method of claim 16, wherein the event window is produced by an equation:

event window=A−

B*(heart rate)−

C*d(heart rate)/dT

where A, B, and C are constants and d(heart rate)/dT is a ventricular rate trajectory being one of the one or more time derivatives generated using the plurality of intervals.

19. The method of claim 18, wherein C is a coefficient for adjusting the variation of the event window for different time derivative values.