Automatic rate-adaptive pacing with auto-lifestyle

• US 6,490,485 B1
• Filed: 10/06/1999
• Issued: 12/03/2002
• Est. Priority Date: 10/06/1999
• Status: Expired due to Term

• Current Assignee: Cardiac Pacemakers Incorporated (Boston Scientific Corporation)
• Original Assignee: Cardiac Pacemakers Incorporated (Boston Scientific Corporation)
• Inventors: Lang, Douglas J., KenKnight, Bruce H., Sun, Weimin
• Primary Examiner(s): Schaetzle, Kennedy
• Assistant Examiner(s): DROESCH, KRISTEN L
• Application Number:
  US09/413,663
• Time in Patent Office: 1,154 Days
• Field of Search: 607/17-20, 607/27
• US Class Current: 607/20
• CPC Class Codes: A61N 1/365 controlled by a physiological parameter, e.g. heart potential evoked response A61N1/371

Abstract

Methods of adjusting output mapping in response to historical signal input data relative to a reference value, and apparatus to perform the methods. The methods are suited for use in adjusting rate-adaptive pacemakers in response to a patient'"'"'s demonstrated activity relative to a predetermined activity level. The methods include using historical physiologic sensor input to derive a patient'"'"'s activity. The methods further include tuning a rate-adaptive curve in response to a demonstrated exertion level and a demonstrated exertion time indicative of a breadth and frequency of a patient'"'"'s activity above some reference value. Pacemakers adapted to perform the methods include a processor, at least one physiologic sensor, a variable-rate pulse generator and a memory for storing historical physiologic sensor data.

Claims

1. A method of adjusting an at least two-slope rate-adaptive curve for pacing a patient'"'"'s heart, the curve including at least one breakpoint between slopes, the method comprising:

sensing the patient'"'"'s activity and producing sensed activity data therefrom;

generating a demonstrated activity level from the sensed activity data; and

adjusting at least one of a slope and a breakpoint of the at least two-slope rate-adaptive curve in response to the demonstrated activity level relative to a predetermined activity level.

2. The method of claim 1, wherein sensing the patient'"'"'s activity further comprises receiving input from at least one physiologic sensor.

3. The method of claim 1, wherein sensing the patient'"'"'s activity further comprises receiving input from at least one physiologic sensor selected from the group consisting of minute ventilation sensors and accelerometers.

4. The method of claim 1, wherein adjusting the rate-adaptive curve further comprises increasing the rate-adaptive curve when the demonstrated activity level exceeds the predetermined activity level.

5. The method of claim 1, wherein adjusting the rate-adaptive curve further comprises decreasing the rate-adaptive curve when the demonstrated activity level is less than the predetermined activity level.

6. The method of claim 1, wherein the predetermined activity level corresponds to a prescribed exercise level and frequency.

11. The method of claim 1, further comprising:

obtaining data from an auxiliary input;

generating historical auxiliary input data from the auxiliary input data, wherein the historical auxiliary input data is indicative of at least one factor selected from the group consisting of a breadth and a frequency of the auxiliary input data in excess of a second reference value; and

adjusting the output mapping in response to the historical auxiliary input data as well as the historical signal input data.

12. The method of claim 11, wherein the first reference value is for comparison to the data from the signal input, and the second reference value is for comparison to the data from the auxiliary input.

7. A method of adjusting an at least two-slope rate-adaptive curve for pacing a patient'"'"'s heart, the curve including at least one breakpoint between slopes, the method comprising:

sensing the patient'"'"'s activity having an exertion level;

generating a factor indicative of a breadth of the patient'"'"'s exertion levels above a predetermined exertion level; and

adjusting at least one of a slope and a breakpoint of the at least two-slope rate-adaptive curve in response to the factor.

8. The method of claim 7, wherein the factor increases for increasing breadth of the patient'"'"'s exertion levels above the predetermined exertion level.

9. A method of adjusting an at least two-slope output mapping of a control output versus a control input, the mapping including at least one breakpoint between slopes, the method comprising:

obtaining signal input data, wherein the signal input data comprises data from the control input;

generating historical signal input data from the signal input data, wherein the historical signal input data is indicative of a frequency of the signal input data in excess of a first reference value; and

adjusting at least one of a slope and a breakpoint of the at least two-slope output mapping in response to the historical signal input data.

10. The method of claim 9, wherein adjusting the output mapping includes increasing an area of the output mapping in response to increasing values of the at least one factor.

13. A method of adjusting an at least two-slope output mapping of a control output versus a control input, the mapping including at least one breakpoint between slopes, the method comprising:

obtaining signal input data, wherein the signal input data comprises data from an auxiliary input;

generating historical signal input data from the signal input data, wherein the historical signal input data is indicative of a frequency of the signal input data in excess of a reference value; and

adjusting at least one of a slope and a breakpoint of the at least two-slope output mapping in response to the historical signal input data.

14. The method of claim 13, wherein adjusting the output mapping includes increasing an area of the output mapping in response to increasing values of the at least one factor.

15. A method of adjusting an at least two-slope rate-adaptive curve for pacing a patient'"'"'s heart, the curve including at least one breakpoint between slopes, the method comprising:

sensing the patient'"'"'s activity and determining both an exertion level, and an exertion time at the exertion level;

generating a first factor indicative of a breadth of the patient'"'"'s exertion levels above a predetermined exertion level;

generating a second factor indicative of the patient'"'"'s exertion time at exertion levels above the predetermined exertion level; and

adjusting at least one of a slope and a breakpoint of the at least two-slope rate-adaptive curve in response to the first and second factors.

16. The method of claim 15, wherein the first factor increases for increasing breadth of the patient'"'"'s exertion levels above the predetermined exertion level.

17. The method of claim 15, wherein the second factor increases for increasing frequency of the patient'"'"'s exertion levels above the predetermined exertion level.

18. A method of adjusting an at least two-slope output mapping of a control output versus a control input, the mapping including at least one breakpoint between slopes, the method comprising:

obtaining signal input data, wherein the signal input data comprises data from the control input;

generating historical signal input data from the signal input data;

generating a first factor indicative of a breadth of the historical signal input data in excess of a reference value;

generating a second factor indicative of a frequency of the historical signal input data in excess of the reference value; and

adjusting at least one of a slope and a breakpoint of the output mapping in response to the first and second factors.

19. The method of claim 18, wherein adjusting the output mapping further comprises increasing an area of the output mapping in response to increasing values of the first factor and decreasing the area of the output mapping in response to decreasing values of the first factor.

20. The method of claim 18, wherein adjusting the output mapping further comprises increasing an area of the output mapping in response to increasing values of the second factor and decreasing an area of the output mapping in response to decreasing values of the second factor.

21. A method of adjusting an at least two-slope output mapping of a control output versus a control input, the mapping including at least one breakpoint between slopes, the method comprising:

obtaining signal input data, wherein the signal input data comprises data from an auxiliary input;

generating historical signal input data from the signal input data;

generating a first factor indicative of a breadth of the historical signal input data in excess of a reference value;

generating a second factor indicative of a frequency of the historical signal input data in excess of the reference value; and

adjusting at least one of a slope and a breakpoint of the at least two-slope output mapping in response to the first and second factors.

22. The method of claim 21, wherein adjusting the output mapping further comprises increasing an area of the output mapping in response to increasing values of the first factor and decreasing the area of the output mapping in response to decreasing values of the first factor.

23. The method of claim 21, wherein adjusting the output mapping further comprises increasing an area of the output mapping in response to increasing values of the second factor and decreasing an area of the output mapping in response to decreasing values of the second factor.

24. A method of adjusting an at least two-slope output mapping of a control output versus a control input, the mapping including at least one breakpoint between slopes, the method comprising:

obtaining data from the control input, thereby producing control input data;

obtaining data from auxiliary input, thereby producing auxiliary input data;

generating historical control input data from the control input data;

generating historical auxiliary input data from the auxiliary input data;

generating a first factor indicative of a breadth of the historical control input data in excess of a first reference value and a breadth of the historical auxiliary input data in excess of a second reference value;

generating a second factor indicative of a frequency of the historical control input data in excess of the first reference value and a frequency of the historical auxiliary input data in excess of the second reference value; and

adjusting at least one of a slope and a breakpoint of the at least two-slope output mapping in response to the first and second factors.

25. The method of claim 24, wherein adjusting the output mapping further comprises increasing an area of the output mapping in response to increasing values of the first factor and decreasing the area of the output mapping in response to decreasing values of the first factor.

26. The method of claim 24, wherein adjusting the output mapping further comprises increasing an area of the output mapping in response to increasing values of the second factor and decreasing an area of the output mapping in response to decreasing values of the second factor.

27. A method of adjusting a two-slope rate-adaptive curve for pacing a patient'"'"'s heart, wherein the two-slope rate-adaptive curve is defined by variables of a heart rate at breakpoint, a sensor target rate, a high heart-rate response factor, a lower endpoint and an upper endpoint, the method comprising:

sensing the patient'"'"'s activity having both an exertion level and an exertion time at the exertion level using at least one physiologic sensor input;

generating a first factor indicative of a breadth of the patient'"'"'s exertion levels above a predetermined exertion level;

generating a second factor, indicative of the patient'"'"'s exertion time at exertion levels above the predetermined exertion level; and

adjusting the variables of the heart rate at breakpoint, the sensor target rate and the high heart-rate response factor in response to the first and second factors.

28. The method of claim 27, wherein adjusting the variables of the heart rate at breakpoint, the sensor target rate and the high heart-rate response factor occur with the lower and upper endpoints constrained.

29. A control system, comprising:

a processor;

a memory coupled to the processor and having first data stored thereon defining an at least two slope output mapping including at least one breakpoint between slopes;

a regulator coupled to the processor;

a control input coupled to the processor; and

a control output coupled to the regulator;

wherein the processor is adapted to sample second data from the control input, store the sampled second data to the memory, generate historical signal input data indicative of a frequency of the second data in excess of a first reference value, and adjust at least one of a slope and a breakpoint of the at least two-slope output mapping in response to the historical signal input data.

30. A control system, comprising:

a processor;

a control input coupled to the processor;

a memory coupled to the processor and having first data stored thereon defining an at least two-slope output mapping including at least one breakpoint between slopes, wherein the output mapping is responsive to data from the control input;

a regulator coupled to the processor;

an auxiliary input coupled to the processor; and

a control output coupled to the regulator;

wherein the processor is adapted to sample second data from the auxiliary input, store the sampled second data to the memory, generate historical signal input data indicative of a frequency of the second data in excess of a first reference value, and adjust at least one of a slope and a breakpoint of the at least two-slope output mapping in response to the historical signal input data.

31. A rate-adaptive pacemaker, comprising:

a processor;

a memory coupled to the processor;

a variable-rate pulse generator coupled to the processor; and

at least one physiologic sensor input coupled to the processor;

wherein the memory has instructions stored thereon capable of causing the processor to perform a method, the method comprising;

storing first data to the memory defining an at least two-slope rate-adaptive curve including at least one breakpoint between slopes;

sampling second data from the at least one physiologic sensor input indicative of a patient'"'"'s activity;

storing the sampled second data to the memory, and generating historical activity data indicative of a frequency of the second data in excess of a first reference value; and

adjusting at least one of a slope and a breakpoint of the at least two-slope rate-adaptive curve in response to the historical activity data.

32. The rate-adaptive pacemaker of claim 31, wherein the at least one physiologic sensor is selected from the group consisting of minute ventilation sensors and accelerometers.

33. The rate-adaptive pacemaker of claim 31, wherein adjusting first data defining the rate-adaptive curve further comprises increasing the rate-adaptive curve when the patient'"'"'s activity exceeds a predetermined activity level.

34. The rate-adaptive pacemaker of claim 33, wherein the predetermined activity level corresponds to a prescribed exercise level and frequency.

35. The rate-adaptive pacemaker of claim 31, wherein adjusting first data defining the rate-adaptive curve further comprises decreasing the rate-adaptive curve when the patient'"'"'s activity is less than a predetermined activity level.

36. The rate-adaptive pacemaker of claim 35, wherein the predetermined activity level corresponds to a prescribed exercise level and frequency.

37. A rate-adaptive pacemaker, comprising:

a processor;

a memory coupled to the processor;

a variable-rate pulse generator coupled to the processor; and

at least one physiologic sensor input coupled to the processor;

wherein the memory has instructions stored thereon capable of causing the processor to perform a method, the method comprising;

storing first data to the memory defining an at least two-slope rate-adaptive curve including at least one breakpoint between slopes;

sampling second data from the at least one physiologic sensor input indicative of a patient'"'"'s activity having an exertion level;

storing the sampled second data to the memory, thereby generating historical activity data;

generating a factor indicative of a breadth of the patient'"'"'s exertion levels above a predetermined exertion level; and

adjusting at least one of a slope and a breakpoint of the at least two-slope rate-adaptive curve in response to the factor.

38. The rate-adaptive pacemaker of claim 37, wherein the factor increases for increasing breadth of the patient'"'"'s exertion levels above the predetermined exertion level.

39. A rate-adaptive pacemaker, comprising:

a processor;

a memory coupled to the processor;

a variable-rate pulse generator coupled to the processor; and

at least one physiologic sensor input coupled to the processor;

wherein the memory has instructions stored thereon capable of causing the processor to perform a method, the method comprising;

storing first data to the memory defining an at least two-slope rate-adaptive curve including at least one breakpoint between slopes;

sampling second data from the at least one physiologic sensor input indicative of a patient'"'"'s activity having an exertion level and an exertion time at the exertion level;

storing the sampled second data to the memory, thereby generating historical activity data;

generating a first factor indicative of a breadth of the patient'"'"'s exertion levels above a predetermined exertion level;

generating a second factor indicative of the patient'"'"'s exertion time at exertion levels above the predetermined exertion level; and

adjusting at least one of a slope and a breakpoint of the at least two-slope rate-adaptive curve in response to the first and second factors.

40. The rate-adaptive pacemaker of claim 39, wherein the first factor increases for increasing breadth of the patient'"'"'s exertion levels above the predetermined exertion level.

41. The rate-adaptive pacemaker of claim 39, wherein the second factor increases for increasing frequency of the patient'"'"'s exertion levels above the predetermined exertion level.

42. A control system, comprising:

a processor;

a memory coupled to the processor;

a regulator coupled to the processor;

a control input coupled to the processor;

at least one auxiliary input coupled to the processor; and

a control output coupled to the regulator;

wherein the memory has instructions stored thereon capable of causing the processor to perform a method, the method comprising;

storing first data to the memory defining an at least two-slope output mapping including at least one breakpoint between slopes;

sampling second data from the control input;

storing the sampled second data to the memory, thereby generating historical control input data;

sampling third data from the at least one auxiliary input;

storing the sampled third data to the memory, thereby generating historical auxiliary input data;

generating a first factor indicative of a breadth of the historical control input data above a first reference value and a breadth of the historical auxiliary input data above a second reference value;

generating a second factor indicative of a frequency of the historical control input data above the first reference value and a frequency of the historical auxiliary input data above the second reference value;

increasing the output mapping in response to increasing values of the first factor and decreasing the output mapping in response to decreasing values of the first factor; and

increasing the output mapping in response to increasing values of the second factor and decreasing the output mapping in response to decreasing values of the second factor.