Cardiac optimization through low-frequency analysis of hemodynamic variables

• US 7,194,306 B1
• Filed: 09/05/2003
• Issued: 03/20/2007
• Est. Priority Date: 09/05/2003
• Status: Active Grant

• Current Assignee: Pacesetter Incorporated (Abbott Laboratories Incorporated)
• Original Assignee: Pacesetter Incorporated (Abbott Laboratories Incorporated)
• Inventors: Turcott, Robert G.
• Primary Examiner(s): LAYNO, CARL HERNANDZ
• Application Number:
  US10/656,603
• Time in Patent Office: 1,292 Days
• Field of Search: None
• US Class Current: 607/17
• 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
• CPC Class Codes: A61N 1/36564 controlled by blood pressure

Abstract

A parameter in an implantable cardiac therapy device (ICTD) is optimized based on analysis of a hemodynamic signal. The method includes receiving a hemodynamic signal; filtering the hemodynamic signal data to isolate low frequency data present therein; and sampling the low frequency data according to a sampling algorithm. The parameter is optimized in the ICTD based on an analysis of the sampled low frequency data.

Claims

1. A method for optimizing a parameter in an implantable cardiac therapy device (ICTD), comprising:

(a) receiving a hemodynamic signal generated by plethysmography;

(b) filtering said hemodynamic signal to isolate low frequency data present therein;

(c) sampling said low frequency data according to a sample algorithm metric; and

(d) adjusting the parameter based on an analysis of said sampled low frequency data.

2. The method of claim 1, wherein said sampling step comprises sampling said low frequency data present in a portion of a frequency spectrum of said hemodynamic signal that is less than about one Hertz (1 Hz).

3. The method of claim 2, wherein said sampling step comprises sampling said low frequency data present in a portion of a frequency spectrum of said hemodynamic signal that is between about 0.1 and about 1.0 Hz.

4. The method of claim 3, wherein said sampling step comprises sampling said low frequency data present in a portion of a frequency spectrum of said hemodynamic signal that is between about 0.03 and about 1.0 Hz.

5. An apparatus for optimizing a parameter in an implantable cardiac therapy device (ICTD), comprising:

a photoplethysmography sensor adapted to generate a hemodynamic signal;

means for receiving a said hemodynamic signal;

means for isolating low frequency data present in said hemodynamic signal;

means for sampling said low frequency data;

means for adjusting the parameter based on an analysis of said sampled low frequency data.

6. The apparatus of claim 5, wherein said receiving means is a programmable microcontroller of the ICTD.

7. The apparatus of claim 5, wherein said isolating means is a low pass filter having a cutoff frequency of approximately one Hertz.

8. An apparatus for optimizing a parameter in an implantable cardiac therapy device (ICTD), comprising:

means for receiving a hemodynamic signal, wherein said hemodynamic signal represents blood pressure;

means for isolating low frequency data present in said hemodynamic signal;

means for sampling said low frequency data;

means for adjusting the parameter based on an analysis of said sampled low frequency data.

9. A method for optimizing atrio-ventricular (AV) delay in an implantable cardiac therapy device (ICTD), comprising:

(a) receiving low frequency hemodynamic data representing a baseline AV-delay;

(b) calculating a baseline average of said data representing said baseline AV-delay;

(c) changing AV-delay to a desired sample point AV-delay;

(d) calculating a new average of data representing said desired sample point AV-delay;

(e) calculating a difference between said baseline average and said new average;

(f) returning to said baseline AV delay;

(g) repeating steps (b) through (f) for a desired number of additional sample point AV-delays, whereby step (e) produces a corresponding difference for each additional sample point AV delay; and

(h) selecting an optimal AV-delay based on said differences.

10. The method of claim 9, wherein said low frequency hemodynamic data exists in a low frequency portion of a hemodynamic signal that is less than about one Hertz.

11. The method of claim 10, wherein said low frequency portion is between about 0.1 Hz and about 1.0 Hz.

12. The method of claim 10, wherein said low frequency portion is between about 0.03 Hz and about 1.0 Hz.

22. The method of claim 9, wherein said filtering step comprises filtering said first and second hemodynamic signals with a band pass filter having a pass band between about 0.03 and about 1.0 Hz.

13. A method for optimizing pacing lead placement in an implantable cardiac device, comprising:

(a) placing a pacing lead in a first position;

(b) receiving a first hemodynamic signal corresponding to said first pacing lead position;

(c) adjusting said pacing lead to a new position;

(d) receiving a new hemodynamic signal corresponding to said new pacing lead position;

(e) comparing said first and new hemodynamic signals;

(f) repeating steps (c) through (e) until no further comparisons are desired; and

(g) selecting a pacing lead position based on said comparisons.

14. The method of claim 13, wherein said receiving steps comprise filtering said first and new hemodynamic signals to isolate low frequency data present therein.

15. The method of claim 14, wherein said filtering step comprises filtering said first and new hemodynamic signals with a low pass filter having a cutoff frequency of about one Hertz.

16. The method of claim 14, wherein said filtering step comprises filtering said first and new hemodynamic signals with a band pass filter having a pass band between about 0.1 and about 1.0 Hz.

17. The method of claim 14, wherein said filtering step comprises filtering said first and new hemodynamic signals with a band pass filter having a pass band between about 0.03 and about 1.0 Hz.

18. A method for optimizing pacing rate cutoff in an implantable cardiac device, comprising:

(a) establishing a first pacing rate;

(b) receiving a first hemodynamic signal representative of said first pacing rate;

(c) establishing a second pacing rate;

(d) receiving a second hemodynamic signal representative of said second pacing rate;

(e) performing a comparison of said first and second hemodynamic signals;

(f) repeating steps (c) through (e) until no further comparisons are desired; and

(g) selecting a pacing rate based on said comparisons.

19. The method of claim 18, wherein said receiving steps comprise filtering said first and second hemodynamic signals to isolate low frequency data present therein.

20. The method of claim 19, wherein said filtering step comprises filtering said first and second hemodynamic signals with a low pass filter having a cutoff frequency of about one Hertz.

21. The method of claim 19, wherein said filtering step comprises filtering said first and second hemodynamic signals with a band pass filter having a pass band between about 0.1 and about 1.0 Hz.

23. A method for optimizing a parameter in an implantable cardiac therapy device (ICTD), comprising:

(a) receiving a hemodynamic signal generated by echocardiography;

(b) filtering said hemodynamic signal to isolate low frequency data present therein;

(c) sampling said low frequency data according to a sample algorithm metric; and

(d) adjusting the parameter based on an analysis of said sampled low frequency data.

24. The method of claim 23, wherein said sampling step comprises sampling said low frequency data present in a portion of a frequency spectrum of said hemodynamic signal that is less than about one Hertz (1 Hz).

25. A method for optimizing a parameter in an implantable cardiac therapy device (ICTD), comprising:

(a) receiving a hemodynamic signal representing blood pressure;

(b) filtering said hemodynamic signal to isolate low frequency data present therein;

(c) sampling said low frequency data according to a sample algorithm metric; and

(d) adjusting the parameter based on an analysis of said sampled low frequency data.

26. The method of claim 25, wherein said sampling step comprises sampling said low frequency data present in a portion of a frequency spectrum of said hemodynamic signal that is less than about one Hertz (1 Hz).

27. A method for optimizing a parameter in an implantable cardiac therapy device (ICTD), comprising:

(a) receiving a hemodynamic signal;

(b) filtering said hemodynamic signal to isolate low frequency data present therein;

(c) sampling said low frequency data according to a sample algorithm metric; and

(d) adjusting an atrio-ventricular delay based on an analysis of said sampled low frequency data.

28. A method for optimizing a parameter in an implantable cardiac therapy device (ICTD), comprising:

(a) receiving a hemodynamic signal;

(b) filtering said hemodynamic signal to isolate low frequency data present therein;

(c) sampling said low frequency data according to a sample algorithm metric; and

(d) adjusting an inter-ventricular delay based on an analysis of said sampled low frequency data.

29. A method for optimizing a parameter in an implantable cardiac therapy device (ICTD), comprising:

(a) receiving a hemodynamic signal;

(b) filtering said hemodynamic signal to isolate low frequency data present therein;

(c) sampling said low frequency data according to a sample algorithm metric; and

(d) adjusting a voltage level for arrhythmia treatment based on an analysis of said sampled low frequency data.

30. A method for optimizing a parameter in an implantable cardiac therapy device (ICTD), comprising:

(a) receiving a hemodynamic signal;

(b) filtering said hemodynamic signal to isolate low frequency data present therein;

(c) sampling said low frequency data according to a sample algorithm metric; and

(d) selecting an arrhythmia treatment modality based on an analysis of said sampled low frequency data.

31. A method for optimizing a parameter in an implantable cardiac therapy device (ICTD), comprising:

(a) receiving a hemodynamic signal;

(b) filtering said hemodynamic signal to isolate low frequency data present therein;

(c) sampling said low frequency data according to a sample algorithm metric; and

(d) adjusting lead placement based on an analysis of said sampled low frequency data.

32. A method for optimizing a parameter in an implantable cardiac therapy device (ICTD), comprising:

(a) receiving a hemodynamic signal;

(b) filtering said hemodynamic signal to isolate low frequency data present therein;

(c) sampling said low frequency data according to a sample algorithm metric; and

(d) selecting pacing electrodes based on an analysis of said sampled low frequency data.

33. A method for optimizing a parameter in an implantable cardiac therapy device (ICTD), comprising:

(a) receiving a hemodynamic signal;

(b) filtering said hemodynamic signal to isolate low frequency data present therein;

(c) sampling said low frequency data according to a sample algorithm metric; and

(d) adjusting a pacing rate cutoff for the ICTD based on an analysis of said sampled low frequency data.