WEARABLE AMBULATORY MEDICAL DEVICE WITH MULTIPLE SENSING ELECTRODES

• US 20160367162A1
• Filed: 08/31/2016
• Published: 12/22/2016
• Est. Priority Date: 05/18/2010
• Status: Active Grant

• Current Assignee: Zoll Medical Corporation (Asahi Kasei Corporation)
• Original Assignee: Zoll Medical Corporation (Asahi Kasei Corporation)
• Inventors: Kaib, Thomas E., Volpe, Shane S., Macho, John D.
• Granted Patent: US 9,931,050 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: A61B 2562/04 Arrangements of multiple sensors of the same type
• CPC Class Codes: A61B 5/0006 ECG or EEG signals
• CPC Class Codes: A61B 5/021 Measuring pressure in heart or blood vessels A61B5/0205 takes precedence
• CPC Class Codes: A61B 5/0245 by using sensing means generating electric signals, i.e. ECG signals
• CPC Class Codes: A61B 5/053 Measuring electrical impedance or conductance of a portion of the body
• CPC Class Codes: A61B 5/0816 Measuring devices for examining respiratory frequency measuring frequency of electric signals G01R23/00
• CPC Class Codes: A61B 5/11 Measuring movement of the entire body or parts thereof, e.g. head or hand tremor, mobility of a limb for measuring pulse A61B5/02 ;A61B5/1038 takes precedence; motion detection to correct for motion artifacts in physiological signals A61B5/721
• CPC Class Codes: A61B 5/1118 Determining activity level
• CPC Class Codes: A61B 5/14542 for measuring blood gases A61B5/14551 takes precedence
• CPC Class Codes: A61B 5/259 using conductive adhesive means, e.g. gels
• CPC Class Codes: A61B 5/282 Holders for multiple electrodes for introduction into the body A61B5/287
• CPC Class Codes: A61B 5/316 Modalities, i.e. specific diagnostic methods
• CPC Class Codes: A61B 5/349 Detecting specific parameters of the electrocardiograph cycle
• CPC Class Codes: A61B 5/35 by template matching
• CPC Class Codes: A61B 5/364 Detecting abnormal ECG interval, e.g. extrasystoles, ectopic heartbeats
• CPC Class Codes: A61B 5/4836 Diagnosis combined with treatment in closed-loop systems or methods A61B5/0036 takes precedence
• CPC Class Codes: A61B 5/6804 Garments; Clothes
• CPC Class Codes: A61B 5/6805 Vests
• CPC Class Codes: A61B 5/6823 Trunk, e.g., chest, back, abdomen, hip
• CPC Class Codes: A61B 5/7207 of noise induced by motion artifacts
• CPC Class Codes: A61B 5/7221 : Determining signal validity, reliability or quality A61B5/7207 and A61B5/7217 take precedence
• CPC Class Codes: A61N 1/046 : Specially adapted for shock therapy, e.g. defibrillation
• CPC Class Codes: A61N 1/0484 : Garment electrodes worn by the patient
• CPC Class Codes: A61N 1/3904 : External heart defibrillators [EHD]
• CPC Class Codes: A61N 1/3987 : characterised by the timing or triggering of the shock

Abstract

An ambulatory medical device including a plurality of electrodes configured to be disposed at spaced apart positions about a patient'"'"'s body, an electrode signal acquisition circuit, and a monitoring circuit. The acquisition circuit has a plurality of inputs each electrically coupled to a respective electrode of the plurality of electrodes and is configured to sense a respective signal provided by a plurality of different pairings of the plurality of electrodes. The monitoring circuit is electrically coupled to an output of the acquisition circuit and is configured to analyze the respective signal provided by each of the plurality of different pairings and to instruct the acquisition circuit to select at least one of the plurality of different pairings to monitor based on at least one of the quality of the respective signal, a phase difference between the respective signal and that of other pairings, a position of electrodes relative to the patient'"'"'s body, and other criteria.

Claims

1. A wearable monitoring device, comprising:

at least two ECG channels corresponding to different pairings of a plurality of ECG sensing electrodes, wherein the plurality of ECG sensing electrodes are configured to be disposed at spaced apart positions about a body of a patient;

at least one activity sensor configured to monitor a physical activity of the patient;

an electrode signal acquisition circuit configured to be electrically coupled to the plurality of ECG sensing electrodes of the at least two ECG channels and configured to sense respective signals provided by the at least two ECG channels; and

a monitoring and detection circuit electrically coupled to an output of the electrode signal acquisition circuit, the monitoring and detection circuit including at least one processor configured to

instruct the electrode signal acquisition circuit to analyze the respective signals provided by the at least two ECG channels,

select one or more of the at least two ECG channels to monitor based on analysis of the respective signals provided by the at least two ECG channels and the monitored physical activity of the patient, and

determine a presence of an arrhythmia condition based on the respective signals from the selected one or more of the at least two ECG channels.

2. The wearable monitoring device of claim 1, wherein at least one of the at least two ECG channels is based on two or more ECG sensing electrodes of the plurality of ECG sensing electrodes that are selected to be paired together to form the at least one of the at least two ECG channels.

3. The wearable monitoring device of claim 1, wherein the plurality of ECG sensing electrodes include at least three ECG sensing electrodes.

4. The wearable monitoring device of claim 1, wherein one or more of the plurality of ECG sensing electrodes comprises adhesive ECG sensing electrodes.

5. The wearable monitoring device of claim 4, wherein the plurality of ECG sensing electrodes are not all located in a common plane.

6. The wearable monitoring device of claim 1, wherein the monitoring and detection circuit is configured to analyze the respective signals provided by each of the at least two ECG channels and to instruct the electrode signal acquisition circuit to select the one or more of the at least two ECG channels to monitor based upon a quality of the respective signals provided by each of the at least two ECG channels.

7. The wearable monitoring device of claim 1, wherein the at least one processor is configured to instruct the electrode signal acquisition circuit to select a different ECG channel to monitor in response to a detected event.

8. The wearable monitoring device of claim 7, wherein the detected event is strenuous physical activity of the patient.

9. The wearable monitoring device of claim 7, wherein the detected event is movement of the patient.

10. A wearable monitoring device for monitoring electrical activity of a patient'"'"'s heart, comprising:

at least two ECG channels corresponding to different pairings of a plurality of ECG sensing electrodes, wherein the plurality of ECG sensing electrodes are configured to be disposed at spaced apart positions about a body of a patient;

an electrode signal acquisition circuit configured to be electrically coupled to the plurality of ECG sensing electrodes and configured to sense respective signals provided by the at least two ECG channels, wherein each of the respective signals represents a different view of the electrical activity of the patient'"'"'s heart; and

a monitoring and detection circuit electrically coupled to an output of the electrode signal acquisition circuit, the monitoring and detection circuit including at least one processor configured to

instruct the electrode signal acquisition circuit to analyze a first ECG channel of the at least two ECG channels,

determine a presence of an arrhythmia condition based on analysis of the first ECG channel, and

instruct the electrode signal acquisition circuit to analyze a second ECG channel, different than the first ECG channel, to assess a confidence level in the determined arrhythmia condition based on the analysis of the first ECG channel.

11. The wearable monitoring device of claim 10, wherein at least one of the at least two ECG channels is based on two or more ECG sensing electrodes of the plurality of ECG sensing electrodes that are selected to be paired together to form the at least one of the at least two ECG channels.

12. The wearable monitoring device of claim 10, wherein the plurality of ECG sensing electrodes includes at least three ECG sensing electrodes.

13. The wearable monitoring device of claim 10, wherein one or more of the plurality of ECG sensing electrodes comprises adhesive ECG sensing electrodes.

14. The wearable monitoring device of claim 13, wherein the plurality of ECG sensing electrodes are not all located in a common plane.

15. The wearable monitoring device of claim 13, further comprising at least one electrode configured to be directly attached to the body of the patient and configured to deliver a defibrillating shock to the body of the patient.

16. The wearable monitoring device of claim 10, wherein the at least one processor is further configured to determine whether the arrhythmia condition is present on the second ECG channel.

17. The wearable monitoring device of claim 16, wherein the at least one processor is configured to increase the confidence level in the determined arrhythmia condition responsive to a determination that the arrhythmia condition is present on the second ECG channel and to decrease the confidence level in the determined arrhythmia condition responsive to a determination that the arrhythmia condition is not present on the second ECG channel.

18. The wearable monitoring device of claim 16, wherein the confidence level is assessed based on whether the arrhythmia condition is present on the second ECG channel and a quality of the respective signals provided by each of the first ECG channel and the second ECG channel.

19. A wearable monitoring device, comprising:

a plurality of ECG channels corresponding to different pairings of a plurality of ECG sensing electrodes, wherein the plurality of ECG sensing electrodes are configured to be disposed at spaced apart positions about a body of a patient;

an electrode signal acquisition circuit configured to be electrically coupled to the plurality of ECG sensing electrodes of the plurality of ECG channels and configured to sense respective signals provided by the plurality of ECG channels; and

a monitoring and detection circuit electrically coupled to an output of the electrode signal acquisition circuit, the monitoring and detection circuit including at least one processor configured to

instruct the electrode signal acquisition circuit to analyze the respective signals provided by the plurality of ECG channels,

select one or more of the plurality of ECG channels to monitor based upon at least a quality of each of the respective signals provided by the plurality of ECG channels, and

determine a presence of an arrhythmia condition based on the respective signals from the selected one or more of the plurality of ECG channels.

20. A method of monitoring ECG signals, comprising:

sensing respective ECG signals provided by at least two ECG channels, each ECG channel of the at least two ECG channels corresponding to different pairings of a plurality of ECG sensing electrodes disposed at spaced apart positions about a body of a patient;

analyzing the respective ECG signals provided by each of the at least two ECG channels;

monitoring a physical activity of the patient;

selecting one or more of the at least two ECG channels to monitor based on the analysis of the respective ECG signals and the monitored physical activity of the patient; and

determining a presence of an arrhythmia condition based on respective ECG signals from the selected one or more of the at least two ECG channels.

21. The method of monitoring ECG signals of claim 20, further comprising selecting a different ECG channel than the selected one or more of the at least two ECG channels to monitor and determining whether the arrhythmia condition is also present on the different ECG channel.

22. The method of monitoring ECG signals of claim 20, wherein selecting the one or more of the at least two ECG channels is further based upon a quality of the respective ECG signals provided by each of the at least two ECG channels.

23. The method of monitoring ECG signals of claim 20, wherein selecting one or more of the at least two ECG channels further comprises:

detecting an event; and

selecting a different one of the at least two ECG channels to monitor responsive to the detected event.