Metrics of electrical dyssynchrony and electrical activation patterns from surface ECG electrodes

• US 9,474,457 B2
• Filed: 02/26/2014
• Issued: 10/25/2016
• Est. Priority Date: 06/12/2013
• Status: Active Grant

• Current Assignee: Medtronic Incorporated (Medtronic Plc)
• Original Assignee: Medtronic Incorporated (Medtronic Plc)
• Inventors: Ghosh, Subham, Gillberg, Jeffrey M
• Primary Examiner(s): Alter, Alyssa M
• Application Number:
  US14/190,578
• Publication Number:
  US 20140371808A1
• Time in Patent Office: 972 Days
• Field of Search: 607/28
• US Class Current: 1/1
• CPC Class Codes: A61B 5/282 Holders for multiple electrodes for introduction into the body A61B5/287
• CPC Class Codes: A61B 5/349 Detecting specific parameters of the electrocardiograph cycle
• CPC Class Codes: A61B 5/353 Detecting P-waves
• CPC Class Codes: A61B 5/355 Detecting T-waves
• CPC Class Codes: A61B 5/6805 Vests
• CPC Class Codes: A61B 5/7282 Event detection, e.g. detecting unique waveforms indicative of a medical condition A61B5/4094, A61B5/4818, A61B5/349, A61B5/0823 take precedence
• 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 1/3682 with a variable atrioventricular delay
• CPC Class Codes: A61N 1/3684 for stimulating the heart at multiple sites of the ventricle or the atrium
• CPC Class Codes: A61N 1/36842 Multi-site stimulation in the same chamber
• CPC Class Codes: A61N 1/36843 Bi-ventricular stimulation

Abstract

A method and system of cardiac pacing is disclosed. A baseline rhythm is determined using a plurality of body-surface electrodes. A set of baseline functional electrical metrics is determined in response to determining the baseline rhythm. Resynchronization pacing is delivered using a right ventricular electrode and a pacing left ventricular electrode or only with a left ventricular electrode. A set of functional electrical metrics relating to cardiac depolarization and repolarization is determined in response to resynchronization pacing. A determination is made as to whether relative reduction of at least one functional electrical metric from the set of functional electrical metrics exceeds X % of its corresponding value from the set of baseline functional electrical metrics. A determination is made as to whether an absolute value of at least one electrical metric from the set of the functional electrical metrics is less than Y ms. A determination is made as to whether a site is responsive to cardiac resynchronization therapy (CRT).

Claims

1. A method of cardiac pacing comprising:

a) sensing heart activity using a plurality of body-surface electrodes;

(b) using a processor to determine

(i) a baseline rhythm from the sensed heart activity; and

(ii) a set of baseline functional electrical metrics based upon the baseline rhythm;

(c) delivering resynchronization pacing using a right ventricular electrode and pacing a left ventricular electrode or only pacing with a left ventricular electrode;

(d) using the processor to determine a set of functional electrical metrics relating to cardiac depolarization and repolarization in response to the resynchronization pacing;

(e) using the processor to determine whether relative reduction of at least one functional electrical metric from the set of functional electrical metrics in step d exceeds X % of its corresponding value from the set of baseline functional electrical metrics in step b;

(f) in response to determining that relative reduction of at least one functional electrical metric from the set of functional electrical metrics in step d exceeds X %, using the processor to determine whether an absolute value of at least one electrical metric from the set of the functional electrical metrics in step d is less than Y ms; and

(g) using the processor to determine that a site is responsive to cardiac resynchronization therapy (CRT) in response to determining whether step f) is met.

2. The method of claim 1 wherein the resynchronization pacing using a first SAV or first PAV equal to greater of (intrinsic AV−

60 ms, 80 ms); and

using the processor to determine another set of functional electrical metrics relating to cardiac depolarization and repolarization in response to the resynchronization pacing.

3. The method of claim 2 further comprising:

using the processor to determine whether relative reduction of at least one functional electrical metric from the set of functional electrical metrics in the step of claim 2 exceeds X % of its corresponding value from the set of baseline functional electrical metrics.

4. The method of claim 3 wherein

the resynchronization pacing using a second SAV or a second PAV equal to greater of (intrinsic AV−

30 ms, 80 ms); and

using the processor to determine another set of functional electrical metrics relating to cardiac depolarization and repolarization in response to the resynchronization pacing.

5. The method of claim 4 further comprising:

using the processor to determine whether relative reduction of at least one functional electrical metric from the set of functional electrical metrics in the step of claim 2 exceeds X % of its corresponding value from the set of baseline functional electrical metrics.

6. The method of claim 3 further comprising:

in response to determining relative reduction of at least one functional electrical metric from the set of functional electrical metrics in the step of claim 2 exceeds X %, using the processor to determine whether an absolute value of at least one electrical metric from the set of the functional electrical metrics is less than Y ms; and

in response to determining the absolute value of at least one electrical metric from the set of the functional electrical metrics is less than Y ms, using the processor to determine that a site is responsive to cardiac resynchronization therapy (CRT).

7. The method of claim 3 further comprising:

in response to determining relative reduction of at least one functional electrical metric from the set of functional electrical metrics in the step of claim 2 does not exceed X %, delivering resynchronization pacing using a right ventricular electrode and a pacing left ventricular electrode or only pacing with a left ventricular electrode, the resynchronization pacing using a SAV or PAV equal to greater of (intrinsic AV−

90 ms, 80 ms).

8. The method of claim 3 further comprising:

in response to determining relative reduction of at least one functional electrical metric from the set of functional electrical metrics in the step of claim 2 does not exceed X %, delivering resynchronization pacing using a right ventricular electrode and a pacing left ventricular electrode or only pacing with a left ventricular electrode, the resynchronization pacing using a SAV or PAV equal to greater of (intrinsic AV−

30 ms, 80 ms).

9. The method of claim 7 further comprising:

determining whether relative reduction of at least one functional electrical metric from the set of functional electrical metrics exceeds X % of its corresponding value from the set of baseline functional electrical metrics.

10. The method of claim 9, further comprising:

using the processor to determine that a site is responsive to cardiac resynchronization therapy (CRT) in response to determining whether a step in claim 7 is met.

11. The method of claim 9, further comprising:

using the processor to determine that a site is nonresponsive to cardiac resynchronization therapy (CRT) in response to determining whether a step in claim 7 is not met.

12. The method of claim 9, further comprising:

using the processor to determine whether an absolute value of at least one electrical metric from the set of the functional electrical metrics is less than Y ms; and

in response to determining the absolute value of at least one electrical metric from the set of the functional electrical metrics is less than Y ms, determining that a site is responsive to cardiac resynchronization therapy (CRT).

13. The method of claim 1 wherein functional electrical metrics are indicative of electrical dyssynchrony during a cardiac depolarization process and dispersion of repolarization during a cardiac repolarization process.

14. The method of claim 13 wherein the functional electrical metrics are associated with at least one resynchronization of activation metric.

15. The method of claim 14 wherein the resynchronization of activation metric relates to dispersion of electrical activation times corresponding to a plurality of surface electrodes on a torso or on certain predefined anatomic areas of the torso.

16. The method of claim 15 wherein at least one resynchronization of activation metric is standard deviation of activation times acquired from the plurality of body-surface electrodes.

17. The method of claim 15 wherein at least one resynchronization of activation metric is standard deviation of activation times of only left-sided electrodes of the plurality of body-surface electrodes.

18. The method of claim 14 wherein at least one resynchronization of activation metric is associated with central tendency of electrical activation times corresponding to the plurality of body-surface electrodes on a torso or on certain predefined anatomic areas of the torso.

19. The method of claim 18 wherein the central tendency of electrical activation times reflects one of an average global activation time and an average regional activation time.

20. The method of claim 1, wherein X % ranges from about 5% to about 100%.

21. The method of claim 1, wherein Y ranges from about 15 ms to about 150 ms.

22. The method of claim 1 wherein a measure of dispersion may include standard deviation, range or interquartile deviation of activation times, repolarization times, activation-recovery intervals associated with a plurality of surface electrodes.

23. The method of claim 1, wherein central tendency is one of a mean, a median, mode or a sum of absolute values of activation times associated with a plurality of surface electrodes.

24. A system of cardiac pacing comprising:

(a) sensing heart activity using a plurality of body-surface electrodes;

(b) using a processor means for determining;

a baseline rhythm sensed from the heart activity; and

a set of baseline functional electrical metrics from the baseline rhythm;

(c) delivering resynchronization pacing using a right ventricular electrode and a pacing left ventricular electrode or only with a left ventricular electrode;

(d) using the processor means for determining;

(i) a set of functional electrical metrics relating to cardiac depolarization and repolarization in response to resynchronization pacing;

(ii) whether relative reduction of at least one functional electrical metric from the set of functional electrical metrics in step d exceeds X % of its corresponding value from the set of baseline functional electrical metrics in step b;

(f) in response to determining that relative reduction of at least one functional electrical metric from the set of functional electrical metrics in step d exceeds X %, using the processor means for determining whether an absolute value of at least one electrical metric from the set of the functional electrical metrics in step d is less than Y ms; and

(g) the processor means for determining that a site is responsive to cardiac resynchronization therapy (CRT) in response to determining whether step f) is met.

25. The system of claim 24 further comprising:

delivering resynchronization pacing using a right ventricular electrode and a pacing left ventricular electrode or only with a left ventricular electrode, the resynchronization pacing using a first SAV or first PAV equal to greater of (intrinsic AV−

60 ms, 80 ms); and

the processor means for determining another set of functional electrical metrics relating to cardiac depolarization and repolarization in response to resynchronization pacing.

26. The system of claim 25 further comprising:

the processor means for determining whether relative reduction of at least one functional electrical metric from the set of functional electrical metrics in the step of claim 24 exceeds X % of its corresponding value from the set of baseline functional electrical metrics.

27. The system of claim 26 further comprising:

delivering resynchronization pacing using a right ventricular electrode and a pacing left ventricular electrode or only with a left ventricular electrode, the resynchronization pacing using a second SAV or a second PAV equal to greater of (intrinsic AV−

30 ms, 80 ms); and

the processor means for determining another set of functional electrical metrics relating to cardiac depolarization and repolarization in response to resynchronization pacing.

28. The system of claim 27 further comprising:

the processor means for determining whether relative reduction of at least one functional electrical metric from the set of functional electrical metrics in the step of claim 25 exceeds X % of its corresponding value from the set of baseline functional electrical metrics.

29. The system of claim 26 further comprising:

in response to determining relative reduction of at least one functional electrical metric from the set of functional electrical metrics in the step of claim 25 exceeds X %, the processor means for determining whether an absolute value of at least one electrical metric from the set of the functional electrical metrics is less than Y ms; and

in response to determining the absolute value of at least one electrical metric from the set of the functional electrical metrics is less than Y ms, the processor means for determining that a site is responsive to cardiac resynchronization therapy (CRT).

30. The system of claim 26 further comprising:

in response to determining relative reduction of at least one functional electrical metric from the set of functional electrical metrics in the step of claim 25 does not exceed X %, delivering resynchronization pacing using a right ventricular electrode and a pacing left ventricular electrode or only with a left ventricular electrode, the resynchronization pacing using a SAV or PAV equal to greater of (intrinsic AV−

90 ms, 80 ms).

31. The system of claim 26 further comprising:

in response to determining relative reduction of at least one functional electrical metric from the set of functional electrical metrics in the step of claim 25 does not exceed X %, delivering resynchronization pacing using a right ventricular electrode and a pacing left ventricular electrode or only with a left ventricular electrode, the resynchronization pacing using a SAV or PAV equal to greater of (intrinsic AV−

30 ms, 80 ms).

32. The system of claim 30 further comprising:

the processor means for determining whether relative reduction of at least one functional electrical metric from the set of functional electrical metrics exceeds X % of its corresponding value from the set of baseline functional electrical metrics.

33. The system of claim 32, further comprising:

the processor means for determining that a site is responsive to cardiac resynchronization therapy (CRT) in response to determining whether a step in claims 24 to 32 is met.

34. The system of claim 32, further comprising:

the processor means for determining that a site is nonresponsive to cardiac resynchronization therapy (CRT) in response to determining whether a step in claims 24 to 33 is not met.

35. The system of claim 32, further comprising:

the processor means for determining whether an absolute value of at least one electrical metric from the set of the functional electrical metrics is less than Y ms; and

in response to determining the absolute value of at least one electrical metric from the set of the functional electrical metrics is less than Y ms, determining that a site is responsive to cardiac resynchronization therapy (CRT).

36. The system of claim 24 wherein functional electrical metrics are indicative of electrical dyssynchrony during a cardiac depolarization process and dispersion of repolarization during a cardiac repolarization process.

37. The system of claim 36 wherein the functional electrical metrics are associated with at least one resynchronization of activation metric.

38. The system of claim 37 wherein the resynchronization of activation metric relates to dispersion of electrical activation times corresponding to the plurality of body-surface electrodes on a torso or on certain predefined anatomic areas of the torso.

39. The system of claim 38 wherein at least one resynchronization of activation metric is standard deviation of activation times acquired from all torso electrodes.

40. The system of claim 39 wherein at least one resynchronization of activation metric is standard deviation of activation times of only left-sided electrodes of the torso electrodes.

41. The system of claim 37 wherein at least one resynchronization of activation metric is associated with central tendency of electrical activation times corresponding to a plurality of body-surface electrodes on a torso or on certain predefined anatomic areas of the torso.

42. The system of claim 41 wherein the central tendency of electrical activation times reflects one of an average global activation time and an average regional activation time.

43. The system of claim 24, wherein X % ranges from about 5% to about 100%.

44. The system of claim 24, wherein Y ranges from about 15 ms to about 150 ms.

45. The system of claim 24 wherein a measure of dispersion may include standard deviation, range or interquartile deviation of activation times, repolarization times, activation-recovery intervals associated with a plurality of body-surface electrodes.

46. The system of claim 24, wherein central tendency is one of a mean, a median, mode or a sum of absolute values of activation times associated with a plurality of body-surface electrodes.

47. A non-transitory, computer-readable storage medium comprising instructions that, when executed, cause a processor included in a medical device system to:

a) acquiring heart activity from a plurality of body-surface electrodes;

(b) determining a baseline rhythm from the acquired heart activity and a set of baseline functional electrical metrics in response to determining the baseline rhythm;

(c) cause delivery of resynchronization pacing using a right ventricular electrode and a pacing left ventricular electrode or only with a left ventricular electrode;

(d) determining a set of functional electrical metrics relating to cardiac depolarization and repolarization in response to the resynchronization pacing;

(e) determining whether relative reduction of at least one functional electrical metric from the set of functional electrical metrics in step d exceeds X % of its corresponding value from the set of baseline functional electrical metrics in step b;

(f) in response to determining that relative reduction of at least one functional electrical metric from the set of functional electrical metrics in step d exceeds X %, determining whether an absolute value of at least one electrical metric from the set of the functional electrical metrics in step d is less than Y ms; and

(g) determine that a site is responsive to cardiac resynchronization therapy (CRT) in response to determining whether step f) is met.