Method of signal enhancement for ECG devices

• US 8,649,852 B2
• Filed: 05/02/2011
• Issued: 02/11/2014
• Est. Priority Date: 05/02/2011
• Status: Active Grant

• Current Assignee: Medtronic Incorporated (Medtronic Plc)
• Original Assignee: Medtronic Incorporated (Medtronic Plc)
• Inventors: Song, Zhendong, Wang, Sheng
• Primary Examiner(s): Patel, Niketa
• Assistant Examiner(s): Hankins, Lindsey G
• Application Number:
  US13/099,065
• Publication Number:
  US 20120283586A1
• Time in Patent Office: 1,016 Days
• Field of Search: 600/509, 600/508, 600/374, 607/18
• US Class Current: 600/509
• CPC Class Codes: A61B 5/0006 ECG or EEG signals
• CPC Class Codes: A61B 5/282 Holders for multiple electrodes for introduction into the body A61B5/287
• CPC Class Codes: A61B 5/287 Holders for multiple electrodes, e.g. electrode catheters for electrophysiological study [EPS]
• CPC Class Codes: A61B 5/316 Modalities, i.e. specific diagnostic methods
• CPC Class Codes: A61B 5/327 Generation of artificial ECG signals based on measured signals, e.g. to compensate for missing leads
• CPC Class Codes: A61B 5/332 Portable devices specially adapted therefor
• CPC Class Codes: A61B 5/7221 Determining signal validity, reliability or quality A61B5/7207 and A61B5/7217 take precedence

Abstract

An embodiment of the invention comprises a method of monitoring cardiac electrical activity with two or more ECG devices and computing an enhanced cardiac electrical signal from the cardiac electrical signals obtained from the two or more ECG devices. Electrodes of the two or more ECG devices are positioned in a manner to provide an electrical potential difference that is large enough to give useful information about a given ECG signal. The method further includes recommending addition of a supplemental ECG device when it is determined that the one or more of the existing ECG devices are inadequate for providing cardiac electrical data that identifies a specific cardiac event.

Claims

1. A method of monitoring cardiac electrical activity, comprising:

requesting a first cardiac electrical signal from a first ECG device, the first ECG device comprising a first pair of electrodes positioned on longitudinally opposing ends of said first ECG device, wherein

a first electrode of the first pair of electrodes is positioned at a location of maximum electrical potential for a first predetermined ECG signal; and

a second electrode of the first pair of electrodes is positioned along a first equipotential line extending from the location of maximum electrical potential for the first predetermined ECG signal;

receiving the first cardiac electrical signal;

requesting a second cardiac electrical signal from a second ECG device, the second ECG device comprising a second pair of electrodes positioned on longitudinally opposing ends of said second ECG device, wherein

a first electrode of the second pair of electrodes is positioned at a location of minimum electrical potential for the first predetermined ECG signal; and

a second electrode of the second pair of electrodes is positioned along a second equipotential line extending from the location of minimum electrical potential for the first predetermined ECG signal;

receiving the second cardiac electrical signal; and

computing an enhanced cardiac electrical signal based on the first and second cardiac signals, the enhanced cardiac electrical signal representing a larger electrical potential difference than either the electrical potential difference between the first pair of electrodes or the electrical potential difference between the second pair of electrodes.

2. The method of claim 1, wherein

the first pair of electrodes measures an arithmetic difference in an electrical potential between the first and the second electrode of the first pair of electrodes;

the second pair of electrodes measures an arithmetic difference in an electrical potential between the first and the second electrode of the second pair of electrodes; and

the enhanced cardiac electrical signal is an arithmetic sum of the first cardiac electrical signal and the second cardiac electrical signal.

3. The method of claim 1, wherein the first and second ECG devices are both implanted subcutaneously in a patient.

4. The method of claim 1, wherein an arithmetic difference in an electrical potential between the second electrode of the first ECG device and the second electrode of the second ECG device is essentially negligible.

5. The method of claim 1, further comprising

requesting a third cardiac electrical signal from a third ECG device, the third ECG device comprising a third pair of electrodes positioned on longitudinally opposing ends of said third ECG device, wherein

a first electrode of the third pair of electrodes is positioned at a location of either maximum or minimum electrical potential for a second predetermined ECG signal;

and

a second electrode of the third pair of electrodes is positioned along a third equipotential line extending from the location of either maximum or minimum electrical potential for the second predetermined ECG signal;

receiving the third cardiac electrical signal; and

computing a second enhanced cardiac electrical signal based on the first or second cardiac electrical signal and the third cardiac electrical signal, the second enhanced cardiac electrical signal representing a larger electrical potential difference than either the electrical potential difference between the first or second pair of electrodes or the electrical potential difference between the third pair of electrodes.

6. A method of monitoring cardiac electrical activity, comprising:

requesting a first cardiac electrical signal from a first ECG device, the first ECG device comprising a first pair of electrodes positioned on longitudinally opposing ends of said first ECG device, wherein

a first electrode of the first pair of electrodes is positioned at a location of maximum electrical potential for a first predetermined ECG signal; and

a second electrode of the first pair of electrodes is positioned along a first equipotential line extending from the location of maximum electrical potential for the first predetermined ECG signal;

receiving the first cardiac electrical signal;

requesting a second cardiac electrical signal from a second ECG device, the second ECG device comprising a second pair of electrodes positioned on longitudinally opposing ends of said second ECG device, wherein

a first electrode of the second pair of electrodes is positioned at a location of minimum electrical potential for the first predetermined ECG signal; and

a second electrode of the second pair of electrodes is positioned along a second equipotential line extending from the location of minimum electrical potential for the first predetermined ECG signal;

receiving the second cardiac electrical signal; and

computing an enhanced cardiac electrical signal based on the first and second cardiac signals, the enhanced cardiac electrical signal representing a larger electrical potential difference than either the electrical potential difference between the first pair of electrodes or the electrical potential difference between the second pair of electrodes; and

wherein the first and second ECG devices are both implanted subcutaneously in a patient; and

the first ECG device is configured for measuring a plurality of the first cardiac electrical signal over a pre-specified period of time; and

storing the plurality of the first cardiac electrical signal in a memory of the first ECG device;

the second ECG device is configured for measuring a plurality of the second cardiac electrical signal over a pre-specified period of time; and

storing the plurality of the second cardiac electrical signal in a memory of the second ECG device;

requesting the first cardiac electrical signal from said first ECG device comprises requesting the plurality of the first cardiac electrical signal;

receiving the first cardiac electrical signal comprises receiving the plurality of the first cardiac electrical signal from the first ECG device;

requesting the second cardiac electrical signal from said second ECG device comprises requesting the plurality of the second cardiac electrical signal; and

receiving the second cardiac electrical signal comprises receiving the plurality of the second cardiac electrical signal from the second ECG device.

7. The method of claim 6, wherein said plurality of the first cardiac electrical signal received from the first ECG device comprises said plurality of the first cardiac electrical signal for a first period of time, said first period of time including time before and after receiving said request for the plurality of the first cardiac electrical signal;

and

plurality of the second cardiac electrical signal received from the second ECG device comprises said plurality of the second cardiac electrical signal for a second period of time, said second period of time including time before and after receiving said request for the plurality of the second cardiac electrical signal.

8. The method of claim 6, wherein the plurality of the first cardiac electrical signal and the plurality of the second cardiac electrical signal each span a plurality of cardiac cycles.

9. A method of monitoring cardiac electrical activity, comprising

receiving a first cardiac electrical signal, the first cardiac electrical signal being from a first ECG device, said first ECG device comprising a first pair of electrodes positioned on longitudinally opposing ends of said first ECG device, wherein

a first electrode of the first pair of electrodes is positioned at a location of maximum electrical potential for a first predetermined ECG signal;

and

a second electrode of the first pair of electrodes is positioned along a first equipotential line extending from the location of maximum electrical potential for the first predetermined ECG signal;

receiving a second cardiac electrical signal, the second cardiac electrical signal being from a second ECG device, said second ECG device comprising a second pair of electrodes positioned on longitudinally opposing ends of said second ECG device, wherein

a first electrode of the second pair of electrodes is positioned at a location of minimum electrical potential for the first predetermined ECG signal; and

a second electrode of the second pair of electrodes is positioned along a second equipotential line extending from the location of minimum electrical potential for the first predetermined ECG signal; and

computing a first enhanced cardiac electrical signal based on the first and second cardiac electrical signals, the first enhanced cardiac electrical signal representing a larger electrical potential difference than either the electrical potential difference between the first pair of electrodes or the electrical potential difference between the second pair of electrodes.

10. The method of claim 9, wherein

the first pair of electrodes measures an arithmetic difference in an electrical potential between the first and the second electrode of the first pair of electrodes;

the second pair of electrodes measures an arithmetic difference in an electrical potential between the first and the second electrode of the second pair of electrodes; and

the first enhanced cardiac electrical signal is an arithmetic sum of the first cardiac electrical signal and the second cardiac electrical signal.

11. The method of claim 9, wherein an arithmetic difference in an electrical potential between the second electrode of the first ECG device and the second electrode of the second ECG device is essentially negligible.

12. The method of claim 9, further comprising

receiving a third cardiac electrical signal from a third ECG device, the third ECG device comprising a third pair of electrodes positioned on longitudinally opposing ends of said third ECG device, wherein

a first electrode of the third pair of electrodes is positioned at a location of either maximum or minimum electrical potential for a second predetermined ECG signal;

and

a second electrode of the third pair of electrodes is positioned along a third equipotential line extending from the location of either maximum or minimum electrical potential for the second predetermined ECG signal; and

computing a second enhanced cardiac electrical signal based on the first or second cardiac electrical signal and the third cardiac electrical signal, the second enhanced cardiac electrical signal representing a larger electrical potential difference than either the electrical potential difference between the first or second pair of electrodes or the electrical potential difference between the third pair of electrodes.

13. A method of monitoring cardiac electrical activity, comprising

receiving a first cardiac electrical signal, the first cardiac electrical signal being from a first ECG device, said first ECG device comprising a first pair of electrodes positioned on longitudinally opposing ends of said first ECG device, wherein

a first electrode of the first pair of electrodes is positioned at a location of maximum electrical potential for a first predetermined ECG signal;

and

a second electrode of the first pair of electrodes is positioned along a first equipotential line extending from the location of maximum electrical potential for the first predetermined ECG signal;

receiving a second cardiac electrical signal, the second cardiac electrical signal being from a second ECG device, said second ECG device comprising a second pair of electrodes positioned on longitudinally opposing ends of said second ECG device, wherein

a first electrode of the second pair of electrodes is positioned at a location of minimum electrical potential for the first predetermined ECG signal; and

a second electrode of the second pair of electrodes is positioned along a second equipotential line extending from the location of minimum electrical potential for the first predetermined ECG signal; and

computing a first enhanced cardiac electrical signal based on the first and second cardiac electrical signals, the first enhanced cardiac electrical signal representing a larger electrical potential difference than either the electrical potential difference between the first pair of electrodes or the electrical potential difference between the second pair of electrodes, wherein;

the first ECG device is configured for

measuring a plurality of the first cardiac electrical signal over a pre-specified period of time; and

storing the plurality of the first cardiac electrical signal in a memory of the first ECG device;

the second ECG device is configured for measuring a plurality of the second cardiac electrical signal over a pre-specified period of time; and

storing the plurality of the second cardiac electrical signal in a memory of the second ECG device;

receiving the first cardiac electrical signal comprises receiving the plurality of the first cardiac electrical signal, the plurality of the first cardiac electrical signal being from the memory of the first ECG device; and

receiving the second cardiac electrical signal comprises receiving the plurality of the second cardiac electrical signal, the plurality of the second cardiac electrical signal being from the memory of the second ECG device.

14. The method of claim 13, wherein said

plurality of the first cardiac electrical signal comprises said plurality of the first cardiac electrical signal for a first period of time, said first period of time including time before and after the plurality of the first cardiac electrical signal is requested;

and

plurality of the second cardiac electrical signal comprises said plurality of the second cardiac electrical signal for a second period of time, said second period of time including time before and after the plurality of the second cardiac electrical signal is requested.

15. The method of claim 13, wherein the plurality of the first cardiac electrical signal and the plurality of the second cardiac electrical signal each span a plurality of cardiac cycles.