Methods and Apparatus to Stimulate Heart Atria

• US 20160339244A1
• Filed: 08/02/2016
• Published: 11/24/2016
• Est. Priority Date: 09/25/2006
• Status: Active Grant

• Current Assignee: Backbeat Medical, LLC
• Original Assignee: Backbeat Medical, Inc.
• Inventors: Levin, Howard, Gelfand, Mark
• Granted Patent: US 10,596,380 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: A61B 5/349 Detecting specific parameters of the electrocardiograph cycle
• CPC Class Codes: A61N 1/3624 occurring in the atrium, i.e. atrial tachycardia
• CPC Class Codes: A61N 1/3627 for treating a mechanical deficiency of the heart, e.g. congestive heart failure or cardiomyopathy
• CPC Class Codes: A61N 1/368 comprising more than one electrode co-operating with different heart regions A61N1/3622, A61N1/3627 take precedence
• CPC Class Codes: A61N 1/3684 for stimulating the heart at multiple sites of the ventricle or the atrium
• CPC Class Codes: A61N 1/36843 Bi-ventricular stimulation
• CPC Class Codes: A61N 1/37235 Aspects of the external programmer

Abstract

A method and apparatus for treatment of hypertension and heart failure by increasing vagal tone and secretion of endogenous atrial hormones by excitory pacing of the heart atria. Atrial pacing is done during the ventricular refractory period resulting in atrial contraction against closed AV valves, and atrial contraction rate that is higher than the ventricular contraction rate. Pacing results in the increased atrial wall stress. An implantable device is used to monitor ECG and pace the atria in a nonphysiologic manner.

Claims

1. A method for treatment of heart failure, the method comprising:

artificially pacing an atrium of a heart of a patient during a period between an end of an atrial refractory period and an end of a ventricular refractory period;

wherein the artificial pacing causes the atrium of the heart to contract against a closed heart valve of the atrium such that the contraction distends a wall of the atrium with blood; and

wherein the distention of the wall results in an increased secretion of at least one of atrial natriuretic peptide and brain natriuretic peptide, which limits at least one of vasoconstriction and sodium retention.

2. The method of claim 1, wherein the artificial pacing causes the atrium to contract during at or after a middle of ventricular systole when the atrium is distended by passive filling with blood.

3. The method of claim 1, wherein the distention of the wall results in increased secretion of atrial natriuretic peptide in the patient to a level that overcomes detriments from reduced atrial contribution to cardiac output.

4. The method of claim 1, further comprising increasing secretion of atrial natriuretic peptide and vasodilation to a level that offsets suboptimal performance of the heart due to reduced atrial contribution to cardiac output.

5. The method of claim 1, further comprising pacing a ventricle of the heart at a first rate, and pacing the atrium at a second rate that is faster than the first rate.

6. The method of claim 5, wherein the second rate is approximately two times the first rate.

7. The method of claim 1, further comprising alternating between a first pacing period of time that comprises the atrium contracting against the closed heart valve and a second pacing period of time that is different from the first pacing period.

8. The method of claim 7, wherein the second pacing period comprises synchronous atria-ventricular pacing.

9. The method of claim 1, wherein artificially pacing the atrium comprises cyclically:

(a) applying artificially induced contractions of the atrium and (b) allowing naturally occurring contractions of the atrium.

10. The method of claim 1, wherein the artificial pacing causes the atrium to contract between a middle and an end of ventricular systole.

11. The method of claim 1, wherein the artificial pacing causes the atrium to contract during heart systole, when a ventricle of the heart is refractory to stimulation.

12. The method of claim 1, wherein the artificial pacing causes the atrium to contract when the heart valve is closed by a ventricular pressure that exceeds a pressure of the atrium.

13. The method of claim 1, wherein the increased secretion of at least one of atrial natriuretic peptide and brain natriuretic peptide reduces at least one of vasoconstriction and sodium retention.

14. A method for pacing a heart of a patient suffering from heart failure, the method comprising:

delivering an excitatory stimulation to an atrium of the heart during a period between an end of an atrial refractory period and an end of a ventricular refractory period;

causing, with the excitatory stimulation, the atrium of the heart to contract against a closed heart valve of the atrium;

causing, with the contraction of the atrium, a pressure rise within the atrium that distends a wall of the atrium;

causing, with the distention of the wall of the atrium, stress of muscle of the wall of the atria; and

causing, with the stress of the muscle of the wall of the atria, release of an atrial hormone that reduces at least one of vasoconstriction and sodium retention.

15. The method of claim 14, wherein the excitatory stimulation is delivered to the atrium at or after a middle of ventricular systole when the atrium is distended by passive filling with blood.

16. The method of claim 14, wherein causing release of the atrial hormone comprises increasing release of the atrial hormone to a level that overcomes detriments from reduced atrial contribution to cardiac output.

17. The method of claim 14, wherein causing release of the atrial hormone comprises increasing release of the atrial hormone and vasodilation to a level that offsets suboptimal performance of the heart due to reduced atrial contribution to cardiac output.

18. The method of claim 14, further comprising pacing a ventricle of the heart at a first rate, and wherein delivering the excitatory stimulation comprising pacing the atrium at a second rate that is faster than the first rate.

19. The method of claim 14, further comprising alternating between a first pacing period of time that comprises the atrium contracting against the closed heart valve and a second pacing period of time that is different from the first pacing period.

20. The method of claim 19, wherein the second pacing period comprises synchronous atria-ventricular pacing.

21. The method of claim 14, wherein the excitatory stimulation is delivered to the atrium between a middle and an end of ventricular systole.

22. The method of claim 14, wherein the excitatory stimulation causes the atrium to contract when the heart valve is closed by a ventricular pressure that exceeds a pressure of the atrium.

23. The method of claim 14, wherein the atrial hormone is one of atrial natriuretic peptide and brain natriuretic peptide.

24. A programmable implantable pacemaker for treatment of heart failure, the pacemaker connectable to at least one electrically conductive lead for connecting to a heart of a patient, and the pacemaker being programmed to generate electrical signals to be conveyed to the heart through the at least one electrically conductive lead, such that the electrical signals artificially pace an atrium of the heart;

wherein the generated electrical signals are configured to deliver excitatory stimulation to the heart following an end of an atrial refractory period and before an end of a ventricular refractory period; and

wherein the excitatory stimulation is configured to cause the atrium to contract against a closed heart valve associated with the atrium such that the contraction distends the atrium with blood, and the distending atrium results in an increased secretion of an atrial hormone that reduces at least one of vasoconstriction and sodium retention.

25. The pacemaker of claim 24, wherein the pacemaker is programmed to deliver the excitatory stimulation at or after a middle of ventricular systole when the atrium is distended by passive filling with blood.

26. The pacemaker of claim 24, wherein the increased secretion of the atrial hormone overcomes detriments from reduced atrial contribution to cardiac output.

27. The pacemaker of claim 24, wherein the increased secretion of the atrial hormone offsets suboptimal performance of the heart due to reduced atrial contribution to cardiac output.

28. The pacemaker of claim 24, wherein the pacemaker is programmed to sense electrical signals generated by the heart and conveyed to the programmable implantable pacemaker through the at least one electrically conductive lead, and based on the sensed electrical signals, determine the atrial refractory period and the ventricular refractory period.

29. The pacemaker of claim 24, wherein the pacemaker is programmed to deliver the excitatory stimulation when the heart valve is closed by a ventricular pressure that exceeds a pressure of the atrium.

30. The pacemaker of claim 24, wherein the pacemaker is programmed to alternate between a first pacing period of time that comprises the atrium contracting against the closed heart valve and a second pacing period of time that comprises synchronous atria-ventricular pacing.

31. The pacemaker of claim 24, wherein the pacemaker is programmed to artificially pace the atrium by cyclically:

(a) causing artificially induced contractions of the atrium and (b) allowing naturally occurring contractions of the atrium.

32. The pacemaker of claim 24, wherein the pacemaker is programmed to pace a ventricle of the heart at a first rate and pace the atrium at a second rate that is faster than the first rate.

33. The pacemaker of claim 24, wherein the excitatory stimulation causes the atrium to contract between a middle and an end of ventricular systole.

34. The pacemaker of claim 24, further comprising one or more electrically conductive leads connected to the pacemaker.

35. The pacemaker of claim 24, wherein the atrial hormone is one of atrial natriuretic peptide and brain natriuretic peptide.

36. A method for treatment of heart failure of a patient, the method comprising:

artificially pacing an atrium of the heart of the patient, wherein the artificial pacing includes delivery of excitatory stimulation to the atrium;

wherein the excitatory stimulation causes the atrium to contract against a closed heart valve associated with the atrium such that the contraction distends the atrium with blood; and

wherein the distending atrium results in a therapeutic increase in secretion of at least one of atrial natriuretic peptide and brain natriuretic peptide, which limits at least one of vasoconstriction and sodium retention.

37. The method of claim 36, further comprising pacing a ventricle of the heart at a normal rate.

38. The method of claim 36, wherein the therapeutic increase in secretion reduces heart failure symptoms of the patient.

39. The method of claim 36, wherein the therapeutic increase in secretion reduces collagen accumulation and a pathologic remodeling that contributes to progressive congestive heart failure.

40. The method of claim 36, wherein the therapeutic increase in secretion provides beneficial physiological and clinical sequelae in the patient.