METHOD AND DEVICE FOR MYOCARDIAL STRESS REDISTRIBUTION

• US 20080234772A1
• Filed: 03/21/2007
• Published: 09/25/2008
• Est. Priority Date: 03/21/2007
• Status: Active Grant

• Current Assignee: Cardiac Pacemakers Incorporated (Boston Scientific Corporation)
• Original Assignee: Cardiac Pacemakers Incorporated (Boston Scientific Corporation)
• Inventors: Shuros, Allan C., Salo, Rodney W., Arcot-Krishnamurthy, Shantha
• Granted Patent: US 7,778,707 B2
• Time in Patent Office: Days
• US Class Current: 607/11
• CPC Class Codes: A61N 1/3627 for treating a mechanical deficiency of the heart, e.g. congestive heart failure or cardiomyopathy

Abstract

Methods and devices are described for delivering electrical stimulation to the heart in a manner that advantageously redistributes myocardial stress during systole for therapeutic purposes in the treatment of, for example, post-MI and HF patients. Pre-excitation pacing may be applied to deliberately de-stress a particular myocardial region that may be expected to undergo deleterious remodeling, such an the area around a myocardial infarct or a hypertrophying region or to deliberately stress a region remote from the pre-excitation pacing site in order to exert a cardioprotective conditioning effect, similar to the beneficial effects of exercise. Pre-excitation pacing may be advantageously combined with inotropic electrical stimulation applied to the stressed region.

Claims

1. An implantable cardiac device, comprising:

a first electrode adapted for disposition near a first myocardial region;

a second electrode adapted for disposition near a second myocardial region remote from the first region;

one or more pulse generators for outputting pacing pulses;

a controller programmed to deliver pacing pulses through a pacing channel in accordance with a programmed pacing mode;

wherein the controller is programmed to configure the first electrode in a pre-excitation pacing channel and to configure the second electrode in an inotropic stimulation channel;

wherein the controller is programmed to operate in a pre-excitation mode that includes delivering pre-excitation pacing pulses through the pre-excitation pacing channel in a manner that pre-excites the first myocardial region relative to the second myocardial region and delivering inotropic stimulation to the second myocardial region.

2. The device of claim 1 wherein the controller is programmed to deliver inotropic stimulation as multiple non-excitatory pulses delivered during a refractory period of the second myocardial region.

3. The device of claim 1 wherein the controller is programmed to deliver inotropic stimulation as non-excitatory sub-threshold pulses.

4. The device of claim 1 wherein the controller is programmed to deliver inotropic stimulation as pacing pulses with higher energy than the pre-excitation pacing pulses and delivered subsequently thereto during a cardiac cycle.

5. The device of claim 1 wherein the controller is programmed to intermittently reconfigure the inotropic stimulation and pre-excitation channels with different electrodes.

6. The device of claim 1 wherein the controller is programmed to operate in a normal operating mode and intermittently switch to the pre-excitation pacing mode according to defined entry and exit conditions.

7. The device of claim 6 wherein the controller is programmed to deliver no pacing therapy during the normal operating mode.

8. The device of claim 6 wherein the controller is programmed to deliver bradycardia pacing therapy during the normal operating mode.

9. The device of claim 6 wherein the controller is programmed to deliver cardiac resynchronization pacing therapy during the normal operating mode.

10. The device of claim 6 wherein the controller is programmed to intermittently deliver inotropic stimulation during the normal operating mode.

11. A method, comprising:

disposing a first electrode near a first myocardial region;

disposing a second electrode near a second myocardial region remote from the first region;

configuring the first electrode in a pre-excitation pacing channel and configuring the second electrode in an inotropic stimulation channel; and

,

operating in a pre-excitation mode that includes delivering pre-excitation pacing pulses through the pre-excitation pacing channel in a manner that pre-excites the first myocardial region relative to the second myocardial region and delivering inotropic stimulation to the second myocardial region.

12. The method of claim 11 wherein the inotropic stimulation is delivered as multiple non-excitatory pulses delivered during a refractory period of the second myocardial region.

13. The method of claim 11 wherein the inotropic stimulation is delivered as non-excitatory sub-threshold pulses.

14. The method of claim 11 wherein the inotropic stimulation is delivered as pacing pulses with higher energy than the pre-excitation pacing pulses and delivered subsequently thereto during a cardiac cycle.

15. The method of claim 11 further comprising intermittently reconfiguring the inotropic stimulation and pre-excitation channels with different electrodes.

16. The method of claim 11 further comprising operating in a normal operating mode and intermittently switching to the pre-excitation pacing mode according to defined entry and exit conditions.

17. The method of claim 16 wherein no pacing therapy is delivered during the normal operating mode.

18. The method of claim 16 wherein bradycardia pacing therapy is delivered during the normal operating mode.

19. The method of claim 16 wherein cardiac resynchronization pacing therapy is delivered during the normal operating mode.

20. The method of claim 16 further comprising intermittently delivering inotropic stimulation during the normal operating mode.