HEMODYNAMIC STABILITY DETECTION DURING ARRHYTHMIA USING RESPIRATION SENSOR

• US 20110201945A1
• Filed: 02/15/2011
• Published: 08/18/2011
• Est. Priority Date: 02/17/2010
• Status: Abandoned Application

• Current Assignee: Cardiac Pacemakers Incorporated (Boston Scientific Corporation)
• Original Assignee: Cardiac Pacemakers Incorporated (Boston Scientific Corporation)
• Inventors: Zhang, Yi, Li, Dan, Sharma, Arjun
• Application Number:
  US13/027,503
• Publication Number:
  US 20110201945A1
• Time in Patent Office: Days
• US Class Current: 600/484
• CPC Class Codes: A61B 5/0205 Simultaneously evaluating both cardiovascular conditions and different types of body conditions, e.g. heart and respiratory condition
• CPC Class Codes: A61B 5/021 Measuring pressure in heart or blood vessels A61B5/0205 takes precedence
• CPC Class Codes: A61B 5/024 Detecting, measuring or recording pulse rate or heart rate A61B5/0205, A61B5/021 take precedence
• CPC Class Codes: A61B 5/0816 Measuring devices for examining respiratory frequency measuring frequency of electric signals G01R23/00
• CPC Class Codes: A61B 5/318 Heart-related electrical modalities, e.g. electrocardiography [ECG]
• CPC Class Codes: A61N 1/3622 comprising two or more electrodes co-operating with different heart regions
• CPC Class Codes: A61N 1/36521 the parameter being derived from measurement of an electrical impedance
• CPC Class Codes: A61N 1/36542 controlled by body motion, e.g. acceleration
• CPC Class Codes: A61N 1/36578 controlled by mechanical motion of the heart wall, e.g. measured by an accelerometer or microphone
• CPC Class Codes: A61N 1/36585 controlled by two or more physical parameters
• CPC Class Codes: A61N 1/39622 Pacing therapy

Abstract

Detected changes in respiration parameters, either alone or in conjunction with other physiological signals, can be used to discriminate between hemodynamically stable and hemodynamically unstable tachyarrhythmias.

Claims

1. An apparatus comprising:

a cardiac rhythm management device comprising;

a tachyarrhythmia detection circuit configured to detect whether tachyarrhythmia is present in a subject;

a respiration sensing circuit, coupled to the tachyarrhythmia detection circuit, configured to sense a respiration signal from the subject;

an auxiliary sensing circuit, coupled to the tachyarrhythmia detection circuit, configured to sense an auxiliary physiological signal from the subject; and

a processor circuit, coupled to the respiration sensing circuit and the auxiliary sensing circuit, the processor circuit configured to;

determine a characteristic of the respiration signal;

determine a characteristic of the auxiliary physiological signal;

determine relationship between the characteristic of the respiration signal and the characteristic of the auxiliary physiological signal; and

use the relationship to determine a hemodynamic stability characteristic of the tachyarrhythmia.

2. The apparatus of claim 1, wherein the auxiliary sensing circuit is configured to sense at least one of a physical activity level, a heart rate, a heart sound, or an acceleration.

3. The apparatus of claim 1, wherein the processor is configured to determine the characteristic of the respiration signal by determining at least one of:

a time rate of change of a respiration rate, a time rate of change of a respiration depth, or a time rate of change of a respiration morphological pattern;

and wherein the processor is configured to determine the characteristic of the respiration signal using the characteristic of the respiration signal determined over multiple cardiac cycles.

4. The apparatus of claim 1, wherein the processor is configured to:

compare the characteristic of the respiration signal to a first threshold value;

compare the characteristic of the auxiliary physiological signal to a second threshold value; and

use the comparisons to determine an indication of at least one of concordance or discordance.

5. The apparatus of claim 4, wherein the processor is configured to determine discordance when the characteristic of the respiration signal exceeds the first threshold value and the characteristic of the auxiliary physiological signal is less than the second threshold value;

and

wherein the processor is configured to declare that the tachyarrhythmia is hemodynamically unstable in response to a determined discordance.

6. The apparatus of claim 4, wherein the processor is configured to determine concordance when:

1) the characteristic of the respiration signal exceeds the first threshold value and the characteristic of the auxiliary physiological signal exceeds the second threshold value;

or

     2) the characteristic of the respiration signal is less than the first threshold value and the characteristic of the auxiliary physiological signal is less than the second threshold value; and

wherein the processor is configured to declare that the tachyarrhythmia is hemodynamically stable in response to a determined concordance.

7. The apparatus of claim 1, wherein the processor is configured to communicate an indication of the hemodynamic stability characteristic of the tachyarrhythmia to a user interface or process.

8. The apparatus of claim 1, wherein the processor is configured to use the hemodynamic stability characteristic of the tachyarrhythmia to control therapy provided to the subject.

9. The apparatus of claim 8, comprising a therapy circuit, coupled to the processor circuit, the therapy circuit configured to provide anti-tachyarrhythmia pacing to the subject when the tachyarrhythmia is classified as ventricular tachyarrhythmia and is hemodynamically stable.

10. The apparatus of claim 8, comprising a therapy circuit, coupled to the processor circuit, the therapy circuit configured to:

provide shock therapy to the subject when the tachyarrhythmia is classified as ventricular tachyarrhythmia and is hemodynamically unstable; and

withhold shock therapy when the tachyarrhythmia is classified as ventricular tachyarrhythmia and is hemodynamically stable.

11. A method comprising:

determining that a tachyarrhythmia is present in a subject;

sensing a respiration signal from the subject;

sensing an auxiliary physiological signal, other than the respiration signal, from the subject;

determining a characteristic of the respiration signal;

determining a characteristic of the auxiliary physiological signal;

determining a relationship between the characteristic of the respiration signal and the characteristic of the auxiliary physiological signal; and

using the relationship to determine a hemodynamic stability characteristic of the tachyarrhythmia.

12. The method of claim 11, wherein sensing an auxiliary physiological signal includes sensing at least one of a physical activity level, a heart rate, a heart sound, or an acceleration.

13. The method of claim 11, wherein determining the characteristic of the respiration signal includes determining at least one of:

a time rate of change of a respiration rate, a time rate of change of a respiration depth, or a time rate of change of a respiration morphological pattern; and

wherein determining the characteristic of the respiration signal includes determining the characteristic of the respiration signal determined over multiple cardiac cycles.

14. The method of claim 11, wherein determining the relationship includes:

comparing the characteristic of the respiration signal to a first threshold value;

comparing the characteristic of the auxiliary physiological signal to a second threshold value; and

using the comparisons to determine an indication of at least one of concordance or discordance.

15. The method of claim 14, comprising:

determining discordance when the characteristic of the respiration signal exceeds the first threshold value and the characteristic of the auxiliary physiological signal is less than the second threshold value; and

declaring that the tachyarrhythmia is hemodynamically unstable in response to a determined discordance.

16. The method of claim 14, comprising:

determining concordance when;

     1) the characteristic of the respiration signal exceeds the first threshold value and the characteristic of the auxiliary physiological signal exceeds the second threshold value;

or

     2) the characteristic of the respiration signal is less than the first threshold value and the characteristic of the auxiliary physiological signal is less than the second threshold value; and

declaring that the tachyarrhythmia is hemodynamically stable in response to a determined concordance.

17. The method of claim 11, comprising communicating an indication of the hemodynamic stability characteristic of the tachyarrhythmia to a user interface or process.

18. The method of claim 11, comprising using the hemodynamic stability characteristic of the tachyarrhythmia to control therapy provided to the subject.

19. The method of claim 18, comprising providing anti-tachyarrhythmia pacing to the subject when the tachyarrhythmia is hemodynamically stable.

20. The method of claim 18, comprising:

providing shock therapy to the subject when the tachyarrhythmia is hemodynamically unstable; and

withholding shock therapy when the tachyarrhythmia is hemodynamically stable.