Method and apparatus for delivering pre-shock defibrillation therapy

• US 20040002739A1
• Filed: 06/28/2002
• Published: 01/01/2004
• Est. Priority Date: 06/28/2002
• Status: Active Grant

• Current Assignee: Cardiac Pacemakers Incorporated (Boston Scientific Corporation)
• Original Assignee: Cardiac Pacemakers Incorporated (Boston Scientific Corporation)
• Inventors: Lovett, Eric G., Lang, Douglas J., Cates, Adam W.
• Granted Patent: US 7,089,055 B2
• Time in Patent Office: Days
• US Class Current: 607/6
• CPC Class Codes: A61N 1/39622 Pacing therapy

Abstract

An apparatus and method is presented for improving cardiac function after successful termination of a tachyarrhythmia such as ventricular fibrillation. A series of electrical stimulation pulses are delivered prior to a defibrillation shock if one or more specific criteria are met.

Claims

1. A cardiac rhythm management device, comprising:

a sensing channel for generating electrograms reflecting cardiac electrical activity;

a defibrillation shocking channel for delivering a defibrillation shock pulse to the heart;

a stimulation channel for delivering stimulation pulses to improve post-shock cardiac function; and

a controller for causing the defibrillation shocking channel to deliver a first defibrillation shock with no preceding stimulation pulses upon detection of a tachyarrhythmia from the sensed electrogram;

wherein the controller is programmed to cause the delivery of a series of stimulation pulses to the heart prior to delivery of a subsequent defibrillation shock if the first defibrillation shock was unsuccessful in terminating the tachyarrhythmia.

2. The device of claim 1 wherein the stimulation channel may additionally be utilized as a pacing channel by the controller.

3. The device of claim 1 wherein the defibrillation shocking channel includes a pair of shock electrodes and further wherein the stimulation channel utilizes the shock electrodes for delivering stimulation pulses.

4. The device of claim 1 wherein the stimulation pulses are in a frequency range approximately between 10 and 100 Hz.

5. The device of claim 1 wherein the series of stimulation pulses delivered to the heart prior to delivery of a subsequent defibrillation shock if the first defibrillation shock was unsuccessful in terminating the tachyarrhythmia is a pulse train of a duration on the order of 100 milliseconds to 2 seconds.

6. The device of claim 1 wherein the stimulation pulses are of a magnitude on the order of 15 to 200 volts.

7. The device of claim 1 wherein the controller is programmed to cause the delivery of a series of stimulation pulses to the heart prior to delivery of a subsequent defibrillation shock if the first defibrillation shock was unsuccessful in terminating the tachyarrhythmia.

8. The device of claim 1 wherein the controller is programmed to cause the delivery of a series of stimulation pulses to the heart prior to delivery of a subsequent defibrillation shock if a specified number of previous defibrillation shocks were unsuccessful in terminating the tachyarrhythmia.

9. The device of claim 1 wherein the controller is programmed to cause the delivery of a series of stimulation pulses to the heart prior to delivery of a subsequent defibrillation shock if the first defibrillation shock was unsuccessful in terminating the tachyarrhythmia and the tachyarrhythmia has been present for a minimum specified time.

10. The device of claim 1 wherein the controller is programmed to deliver subsequent defibrillation shocks with a greater magnitude than the first defibrillation shock if the latter was unsuccessful in terminating the tachyarrhythmia.

11. The device of claim 7 wherein the controller is programmed to cause the delivery of a series of stimulation pulses to the heart prior to delivery of a subsequent defibrillation shock if the first defibrillation shock was unsuccessful in terminating the tachyarrhythmia and the subsequent defibrillation shock is of a minimum specified magnitude.

12. A cardiac rhythm management device, comprising:

a sensing channel for generating electrograms reflecting cardiac electrical activity;

a defibrillation shocking channel for delivering a defibrillation shock pulse to the heart;

a drug delivery device having contained therein a quantity of a pharmacological or neurohumoral agent for improving post-shock cardiac function; and

a controller for causing the defibrillation shocking channel to deliver a first defibrillation shock upon detection of a tachyarrhythmia from the sensed electrogram;

wherein the controller is programmed to cause the delivery of the pharmacological or neurohumoral agent upon detection of a tachyarrhythmia.

13. A method for operating a cardiac rhythm management device, comprising:

generating electrograms reflecting cardiac electrical activity;

delivering a first defibrillation shock upon detection of a tachyarrhythmia from a sensed electrogram; and

delivering a series of stimulation pulses for improving post-shock cardiac function prior to delivery of a subsequent defibrillation shock if the first defibrillation shock was unsuccessful in terminating the tachyarrhythmia, wherein the first defibrillation shock is not preceded by stimulation pulses.

14. The method of claim 13 wherein the stimulation pulses are in a frequency range approximately between 10 and 100 Hz.

15. The method of claim 13 wherein the series of stimulation pulses delivered prior to delivery of a subsequent defibrillation shock if the first defibrillation shock was unsuccessful in terminating the tachyarrhythmia is a pulse train having a duration between 10 and 100 milliseconds.

16. The method of claim 13 wherein the stimulation pulses have an amplitude between 15 and 200 volts.

17. The method of claim 13 wherein the controller is programmed to cause the delivery of a series of stimulation pulses prior to delivery of a subsequent defibrillation shock if the first defibrillation shock was unsuccessful in terminating the tachyarrhythmia.

18. The method of claim 13 further comprising delivering a series of stimulation pulses to the heart prior to delivery of a subsequent defibrillation shock if a specified number of previous defibrillation shocks were unsuccessful in terminating the tachyarrhythmia.

19. The method of claim 13 further comprising delivering a series of stimulation pulses to the heart prior to delivery of a subsequent defibrillation shock if the first defibrillation shock was unsuccessful in terminating the tachyarrhythmia and the tachyarrhythmia has been present for a minimum specified time.

20. The method of claim 13 further comprising delivering a series of stimulation pulses to the heart prior to delivery of a subsequent defibrillation shock if the first defibrillation shock was unsuccessful in terminating the tachyarrhythmia and the subsequent defibrillation shock is of a minimum specified magnitude.