Electrical therapy for diastolic dysfunction

• US 20050102002A1
• Filed: 11/07/2003
• Published: 05/12/2005
• Est. Priority Date: 11/07/2003
• Status: Active Grant

• Current Assignee: Cardiac Pacemakers Incorporated (Boston Scientific Corporation)
• Original Assignee: Cardiac Pacemakers Incorporated (Boston Scientific Corporation)
• Inventors: Salo, Matthew, Salo, Rodney W.
• Granted Patent: US 9,002,452 B2
• Time in Patent Office: Days
• US Class Current: 607/17
• 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 1/36514 controlled by a physiological quantity other than heart potential, e.g. blood pressure controlled by two or more physical parameters A61N1/36585

Abstract

Pacing pulses are delivered to one or more cardiac regions to improve diastolic performance in patients having diastolic dysfunction and/or heart failure. A cardiac pacing system executes a pacing algorithm using a parameter indicative of the diastolic performance as an input. The pacing pulses excite the one or more cardiac regions to redistribute the loading on the ventricular wall during diastole, thereby improving the diastolic performance by lowering the degree of cardiac wall motion dyssynchrony associated with diastolic dysfunction.

Claims

1. A cardiac pacing system comprising:

a sensing circuit to sense at least one cardiac signal;

a pacing circuit to deliver pacing pulses;

a diastolic performance sensor to sense a signal indicative of a diastolic function;

a signal processor adapted to receive and process the signal indicative of the diastolic function, the signal processor including a diastolic performance parameter generator to produce a diastolic performance parameter based on the signal indicative of the diastolic function; and

a pacing controller coupled to the sensing circuit and the pacing circuit, the pacing controller adapted to receive the diastolic performance parameter and control the delivery of the pacing pulses based on the at least one cardiac signal and the diastolic performance parameter.

2. The cardiac pacing system of claim 1, wherein the pacing controller comprises:

a pacing parameter optimization module adapted to receive the diastolic performance parameter and calculate one or more approximately optimal pacing parameters based on at least the diastolic performance parameter; and

a pacing algorithm execution module, coupled to the sensing circuit and the pacing circuit, to control the delivery of the pacing pulses by executing a predetermined pacing algorithm using the one or more approximately optimal pacing parameters.

3. The cardiac pacing system of claim 2, wherein the pacing parameter optimization module comprises a pacing site selector to select one or more pacing sites based on at least the diastolic performance parameter.

4. The cardiac pacing system of claim 2, wherein the pacing parameter optimization module comprises a pacing timing calculator to calculate one or more pacing timing parameters based on at least the diastolic performance parameter.

5. The cardiac pacing system of claim 1, wherein the diastolic performance sensor comprises a pressure sensor to sense a signal indicative of a left ventricular pressure.

6. The cardiac pacing system of claim 5, wherein the pressure sensor comprises a left ventricular pressure sensor.

7. The cardiac pacing system of claim 5, wherein the pressure sensor comprises a left atrial pressure sensor.

8. The cardiac pacing system of claim 5, wherein the pressure sensor comprises a coronary vein pressure sensor.

9. The cardiac pacing system of claim 5, wherein the diastolic performance parameter generator comprises a diastolic pressure detector to detect a left ventricular end diastolic pressure from the signal indicative of the left ventricular pressure.

10. The cardiac pacing system of claim 5, wherein the diastolic performance parameter generator comprises a diastolic pressure timer to measure a time constant related to a decrease in the left ventricular pressure.

11. The cardiac pacing system of claim 1, wherein the diastolic performance sensor comprises a flow sensor to sense a signal indicative of a blood flow.

12. The cardiac pacing system of claim 11, wherein the flow sensor comprises an impedance sensing circuit.

13. The cardiac pacing system of claim 11, wherein the flow sensor includes a pulmonary blood flow sensor adapted to sense a signal indicative of a pulmonary venous blood flow.

14. The cardiac pacing system of claim 13, wherein the diastolic performance parameter generator comprises a velocity detector to calculate an antegrade pulmonary venous blood velocity based on the signal indicative of the pulmonary venous blood flow.

15. The cardiac pacing system of claim 11, wherein the flow sensor includes a mitral blood flow sensor adapted to sense a signal indicative of a blood flow through a mitral valve.

16. The cardiac pacing system of claim 15, wherein the diastolic performance parameter generator comprises a peak detector to detect a peak blood flow from the signal indicative of the blood flow through the mitral valve.

17. The cardiac pacing system of claim 15, wherein the diastolic performance parameter generator comprises a timer to measure a duration of a rapid initial blood flow from the signal indicative of the blood flow through the mitral valve.

18. The cardiac pacing system of claim 15, wherein the diastolic performance parameter generator comprises a timer to measure a time constant related to a decrease in the blood flow through the mitral valve from the signal indicative of the blood flow through the mitral valve.

19. The cardiac pacing system of claim 1, wherein the diastolic performance sensor comprises an acoustic sensor to sense a signal indicative of heart sounds.

20. The cardiac pacing system of claim 19, wherein the acoustic sensor comprises an accelerometer.

21. The cardiac pacing system of claim 19, wherein the acoustic sensor comprises a microphone.

22. The cardiac pacing system of claim 19, wherein the diastolic performance parameter generator comprises a heart sound analyzer to detect a diastolic acoustic noise from the signal indicative of heart sounds.

23. The cardiac pacing system of claim 1, further comprising at least one intracardiac lead coupled to the sensing circuit and the pacing circuit.

24. The cardiac pacing system of claim 23, wherein the at least one intracardiac lead comprises a right ventricular lead.

25. The cardiac pacing system of claim 23, wherein the at least one intracardiac lead comprises a left ventricular lead.

26. The cardiac pacing system of claim 23, wherein the at least one intracardiac lead comprises a transeptal lead.

27. A cardiac rhythm management system comprising:

an implantable pacemaker including;

a sensing circuit to sense at least one cardiac signal;

a pacing circuit to deliver pacing pulses;

a diastolic performance sensor to sense a signal indicative of a diastolic function; and

a pacing algorithm execution module coupled to the sensing circuit, the pacing circuit, the pacing algorithm execution module adapted to receive the at least one cardiac signal and the signal indicative of the diastolic function and control the delivery of the pacing pulses based on a predetermined pacing algorithm, the at least one cardiac signal, and the signal indicative of the diastolic function; and

at least one implantable intracardiac lead coupled to the sensing circuit and the pacing circuit.

28. The cardiac rhythm management system of claim 27, wherein the implantable pacemaker further comprises:

a signal processor, coupled to the diastolic performance sensor, to produce a diastolic performance parameter based on the signal indicative of the diastolic function; and

a pacing parameter optimization module coupled to the signal processor, the pacing parameter optimization module adapted to calculate one or more approximately optimal parameters based on at least the diastolic performance parameter.

29. The cardiac rhythm management system of claim 27, further comprising an external system communicatively coupled to the implantable pacemaker via telemetry, and wherein the implantable pacemaker comprises an implant telemetry module to transmit the signal indicative of the diastolic function to the external system.

30. The cardiac rhythm management system of claim 29, wherein the external system comprises:

an external telemetry module to receive the signal indicative of the diastolic function;

a signal processor, coupled to the external telemetry module, to produce a diastolic performance parameter based on the signal indicative of the diastolic function; and

a pacing parameter optimization module coupled to the signal processor, the pacing parameter optimization module adapted to calculate an approximately optimal parameter based on at least the diastolic performance parameter.

31. The cardiac rhythm management system of claim 30, wherein the external system comprises a programmer.

32. The cardiac rhythm management system of claim 30, wherein the external system comprises:

an external device wirelessly communicating with the implantable pacemaker;

a remote facility to provide access to the implantable pacemaker from a distant location; and

a network providing for communication between the external device and the remote device.

33. The cardiac rhythm management system of claim 27, wherein the diastolic performance sensor comprises a pressure sensor to sensor a signal indicative of a left ventricular pressure.

34. The cardiac rhythm management system of claim 27, wherein the diastolic performance sensor comprises a pulmonary flow sensor to sense a signal indicative of a pulmonary venous blood flow.

35. The cardiac rhythm management system of claim 27, wherein the diastolic performance sensor comprises a mitral flow sensor to sense a signal indicative of a blood flow through a mitral valve.

36. The cardiac rhythm management system of claim 27, wherein the diastolic performance sensor comprises an acoustic sensor to sense a signal indicative of heart sounds.

37. The cardiac rhythm management system of claim 27, wherein the at least one implantable intracardiac lead comprises at least one transeptal lead.

38. A method, comprising:

sensing at least one cardiac signal;

delivering pacing pulses;

sensing a signal indicative of a diastolic function;

deriving a diastolic performance parameter from the signal indicative of the diastolic function; and

executing a predetermined cardiac pacing algorithm using at least the diastolic performance parameter as an input.

39. The method of claim 38, further comprising producing one or more approximately optimal pacing parameters based on at least the diastolic performance parameter, and wherein executing the predetermined cardiac pacing algorithm comprises controlling a delivery of pacing pulses using the one or more approximately optimal pacing parameters.

40. The method of claim 39, wherein producing the one or more approximately optimal pacing parameters comprises selecting one or more pacing sites based on at least the diastolic performance parameter.

41. The method of claim 39, wherein producing the one or more approximately optimal pacing parameters comprises calculating one or more pacing timing parameters based on at least the diastolic performance parameter.

42. The method of claim 39, wherein producing the one or more approximately optimal pacing parameters comprises calculating one or more atrioventricular pacing delays based on at least the diastolic performance parameter.

43. The method of claim 39, wherein producing the one or more approximately optimal pacing parameters comprises calculating one or more interventricular pacing delays based on at least the diastolic performance parameter.

44. The method of claim 38, wherein sensing the signal indicative of the diastolic function comprises sensing a signal indicative of a left ventricular pressure.

45. The method of claim 44, wherein deriving the diastolic performance parameter comprises detecting a left ventricular end diastolic pressure from the signal indicative of the left ventricular pressure.

46. The method of claim 44, wherein deriving the diastolic performance parameter comprises measuring a time constant related to a decrease in the left ventricular pressure.

47. The method of claim 38, wherein sensing the signal indicative of the diastolic function comprises sensing a signal indicative of a pulmonary venous blood flow.

48. The method of claim 47, wherein sensing the signal indicative of the diastolic function comprises sensing a signal indicative of a pulmonary impedance.

49. The method of claim 47, wherein deriving the diastolic performance parameter comprises calculating an antegrade pulmonary venous blood velocity based on the signal indicative of the pulmonary venous blood flow.

50. The method of claim 38, wherein sensing the signal indicative of the diastolic function comprises sensing a signal indicative of a blood flow through a mitral valve.

51. The method of claim 50, wherein sensing the signal indicative of the diastolic function comprises sensing a signal indicative of an impedance.

52. The method of claim 50, wherein deriving the diastolic performance parameter comprises detecting a peak flow from the signal indicative of the blood flow through the mitral valve.

53. The method of claim 50, wherein deriving the diastolic performance parameter comprises detecting a duration of an initial blood flow peak from the signal indicative of the blood flow through the mitral valve.

54. The method of claim 50, wherein deriving the diastolic performance parameter comprises measuring a time constant related to a decrease in the blood flow through the mitral valve from the signal indicative of the blood flow through the mitral valve.

55. The method of claim 38, wherein sensing the signal indicative of the diastolic function comprises sensing a signal indicative of heart sounds.

56. The method of claim 55, wherein deriving the diastolic performance parameter comprises detecting a diastolic acoustic noise from the signal indicative of heart sounds.

57. The method of claim 38, wherein delivering the pacing pulses comprises delivering the pacing pulses to one or more most contractive ventricular regions.

58. The method of claim 57, wherein delivering the pacing pulses comprises delivering the pacing pulses to one or more ventricular septal sites.

59. The method of claim 58, wherein delivering the pacing pulses comprises delivering the pacing pulses to one or more left ventricular septal regions.

60. A method, comprising:

predicting an effectiveness of delivering pacing pulses to improve a measure of diastolic performance; and

delivering the pacing pulses to one or more cardiac regions to improve the diastolic performance after the effectiveness is predicted.

61. The method of claim 60, wherein predicting the effectiveness comprises:

recording a left ventricular echocardiogram;

dividing a left ventricular endocardial wall into multiple regions; and

measuring left ventricular regional endocardial wall displacements over at least one cardiac cycle for each of the regions; and

predicting the effectiveness if the left ventricular regional endocardial wall displacements are significantly non-uniform across the left ventricular endocardial wall.

62. The method of claim 60, further comprising determining one or more electrode sites corresponding to the one or more cardiac regions.

63. The method of claim 62, wherein determining the one or more electrode sites comprises selecting one or more ventricular regions showing most contribution to a left ventricular contraction.

64. The method of claim 63, wherein determining the one or more electrode sites comprises:

recording a left ventricular echocardiogram;

dividing a left ventricular endocardial wall into multiple regions;

measuring left ventricular regional endocardial wall displacements over one cardiac cycle for each of the regions; and

identify one or more regions displaying the largest left ventricular regional endocardial wall displacements covariant with overall left ventricular area or volume changes.

65. The method of claim 60, wherein delivering the pacing pulses to the one or more cardiac regions comprises delivering the pacing pulses to excite one or more left ventricular septal regions.

66. The method of claim 65, further comprising introducing at least one insulated electrode into a septum through a right ventricle.

67. The method of claim 60, further comprising determining a pacing mode.

68. The method of claim 67, wherein delivering the pacing pulses comprising executing a pacing algorithm defining a VDD pacing mode.

69. The method of claim 67, wherein delivering the pacing pulses comprising executing a pacing algorithm defining a DDD pacing mode.

70. The method of claim 60, further comprising determining one or more pacing parameters, including sensing a signal indicative of a diastolic function and deriving the one or more pacing parameters from the sensed signal indicative of the diastolic function.

71. The method of claim 70, further comprising adjusting the one or more pacing parameters dynamically and continuously.

72. The method of claim 70, further comprising adjusting the one or more pacing parameters periodically.

73. The method of claim 70, further comprising adjusting the one or more pacing parameters in response to a change of a cardiac condition.

74. The method of claim 70, wherein determining the one or more pacing parameters comprises determining the one or more pacing parameters to improve at least a measure of systolic performance and a measure of diastolic performance.