Accurate time annotation of intracardiac ECG signals

• US 8,700,136 B2
• Filed: 11/11/2011
• Issued: 04/15/2014
• Est. Priority Date: 11/11/2011
• Status: Active Grant

• Current Assignee: Biosense Webster Incorporated (Johnson & Johnson)
• Original Assignee: Biosense Webster Incorporated (Johnson & Johnson)
• Inventors: Rubinstein, Vladimir
• Primary Examiner(s): Bertram, Eric D.
• Application Number:
  US13/294,412
• Publication Number:
  US 20130123652A1
• Time in Patent Office: 886 Days
• Field of Search: 600/508, 600/509, 600/519
• US Class Current: 600/509
• 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 5/35 by template matching
• CPC Class Codes: A61B 5/367 Electrophysiological study [EPS], e.g. electrical activation mapping or electro-anatomical mapping
• CPC Class Codes: A61B 5/7203 for noise prevention, reduction or removal
• CPC Class Codes: A61B 5/7235 Details of waveform analysis A61B5/349 takes precedence
• CPC Class Codes: A61B 5/7278 Artificial waveform generation or derivation, e.g. synthesising signals from measured signals A61B5/327 takes precedence

Abstract

A method for analyzing signals, including: sensing a time-varying intracardiac potential signal and finding a fit of the time-varying intracardiac potential signal to a predefined oscillating waveform. The method further includes estimating an annotation time of the signal responsive to the fit.

Claims

1. A method for analyzing signals, comprising:

sensing a time-varying intracardiac potential signal;

finding a fit of the time-varying intracardiac potential signal to a predefined oscillating waveform; and

estimating a reference time of occurrence of a characteristic of the signal responsive to the fit,

wherein the time-varying intracardiac potential signal comprises a bipolar signal, and

the predefined oscillating waveform comprises a difference between a first single complete oscillation and a second single complete oscillation.

2. The method according to claim 1, wherein the first single complete oscillation comprises a first single local maximum, a first single local minimum, and a first inflection separating the first local maximum and minimum, and wherein the second single complete oscillation comprises a second single local maximum, a second single local minimum, and a second inflection separating the second local maximum and minimum.

3. The method according to claim 1, wherein the first single complete oscillation and the second complete oscillation are separated by a temporal difference.

4. The method according to claim 3, wherein the temporal difference is a function of a spatial separation of electrodes generating the bipolar signal.

5. The method according to claim 3, wherein the temporal difference is a function of an electrode orientation relative to a propagation direction of an activation wave.

6. A method for analyzing signals, comprising:

sensing a time-varying intracardiac potential signal;

finding a fit of the time-varying intracardiac potential signal to a predefined oscillating waveform; and

estimating a reference time of occurrence of a characteristic of the signal responsive to the fit,

wherein the time-varying intracardiac potential signal comprises a bipolar signal, and

the predefined oscillating waveform comprises a difference between a first Gaussian function first differential and a second Gaussian function first differential.

7. The method according to claim 6, wherein the first Gaussian function first differential is skewed by a first asymmetry factor and the second Gaussian function first differential is skewed by a second asymmetry factor.

8. A method for analyzing signals, comprising:

sensing a time-varying intracardiac potential signal;

finding a fit of the time-varying intracardiac potential signal to a predefined oscillating waveform; and

estimating a reference time of occurrence of a characteristic of the signal responsive to the fit,

wherein the time-varying intracardiac potential signal comprises three or more unipolar signals having temporal differences therebetween, and wherein a propagation direction of an activation wave is a function of the temporal differences.

9. The method according to claim 8, wherein respective electrodes having respective positions generate the three or more unipolar signals, and wherein the respective positions comprise parameters of the function.

10. Apparatus for analyzing signals, comprising:

a sensor configured to sense a time-varying intracardiac potential signal; and

a processor configured to;

find a fit of the time-varying intracardiac potential signal to a predefined oscillating waveform, and estimate a reference times of occurrence of a characteristic of the signal responsive to the fit,

wherein the time-varying intracardiac potential signal comprises a bipolar signal, and

the predefined oscillating waveform comprises a difference between a first single complete oscillation and a second single complete oscillation.

11. The apparatus according to claim 10, wherein the first single complete oscillation comprises a first single local maximum, a first single local minimum, and a first inflection separating the first local maximum and minimum, and wherein the second single complete oscillation comprises a second single local maximum, a second single local minimum, and a second inflection separating the second local maximum and minimum.

12. The apparatus according to claim 10, wherein the first single complete oscillation and the second complete oscillation are separated by a temporal difference.

13. The apparatus according to claim 12, wherein the temporal difference is a function of a spatial separation of electrodes generating the bipolar signal.

14. The apparatus according to claim 12, wherein the temporal difference is a function of an electrode orientation relative to a propagation direction of an activation wave.

15. An apparatus for analyzing signals, comprising:

a sensor configured to sense a time-varying intracardiac potential signal; and

a processor configured to;

find a fit of the time-varying intracardiac potential signal to a predefined oscillating waveform, and estimate a reference times of occurrence of a characteristic of the signal responsive to the fit,

wherein the time-varying intracardiac potential signal comprises a bipolar signal, and

wherein the predefined oscillating waveform comprises a difference between a first Gaussian function first differential and a second Gaussian function first differential.

16. The apparatus according to claim 15, wherein the first Gaussian function first differential is skewed by a first asymmetry factor and the second Gaussian function first differential is skewed by a second asymmetry factor.

17. An apparatus for analyzing signals, comprising:

a sensor configured to sense a time-varying intracardiac potential signal; and

a processor configured to;

find a fit of the time-varying intracardiac potential signal to a predefined oscillating waveform, and estimate a reference times of occurrence of a characteristic of the signal responsive to the fit,

wherein the time-varying intracardiac potential signal comprises three or more unipolar signals having temporal differences therebetween, and wherein a propagation direction of an activation wave is a function of the temporal differences.

18. The apparatus according to claim 17, wherein respective electrodes having respective positions generate the three or more unipolar signals, and wherein the respective positions comprise parameters of the function.