Heart beat coincidence detection

• US 6,662,043 B1
• Filed: 08/03/2000
• Issued: 12/09/2003
• Est. Priority Date: 08/03/2000
• Status: Expired due to Term

• Current Assignee: GE Marquette Medical Systems, Inc. (General Electric Company)
• Original Assignee: GE Marquette Medical Systems, Inc. (General Electric Company)
• Inventors: Shine, David J.
• Primary Examiner(s): Jastrzab, Jeffrey R.
• Assistant Examiner(s): Oropeza, Frances P.
• Application Number:
  US09/632,271
• Time in Patent Office: 1,223 Days
• Field of Search: 600/453, 600/483, 600/509, 600/511, 600/513, 600/510, 600/516
• US Class Current: 600/509
• CPC Class Codes: A61B 5/02411 of foetuses
• CPC Class Codes: A61B 5/4362 Assessing foetal parameters
• CPC Class Codes: A61B 8/02 Measuring pulse or heart rate
• CPC Class Codes: A61B 8/0866 involving foetal diagnosis; pre-natal or peri-natal diagnosis of the baby
• CPC Class Codes: A61B 8/4472 Wireless probes

Abstract

A method of detecting heart beat coincidence includes receiving first and second signals from first and second heart beat sources. The method further includes detecting first heart beat occurrences on the first signal, each first heart beat occurrence having a respective time associated therewith and detecting second heart beat occurrences on the second signal, each second heart beat occurrence having a respective time associated therewith. The method further includes comparing the times of the first and second heart beat occurrences to detect coincidence.

Claims

1. A method of detecting heart beat coincidence, comprising:

receiving first and second signals from first and second heart beat sources, respectively;

detecting first heart beat occurrences on the first signal, each first heart beat occurrence having a respective time associated therewith;

detecting second heart beat occurrences on the second signal, each second heart beat occurrence having a respective time associated therewith; and

comparing the times of the first and second heart beat occurrences to detect coincidence including calculating a plurality of time offsets between the first and second heart beat occurrences and calculating a jitter between a first time offset and a second time offset.

3. The method of claim 1, further comprising generating one of a coincidence signal and a divergence signal based on the plurality of time offsets.

4. The method of claim 3, wherein the plurality of time offsets are defined by a time window.

5. The method of claim 1, wherein the step of comparing includes comparing the jitter to a predetermined jitter value and incrementing a coincidence counter when the jitter is less than the predetermined jitter value.

11. The method of claim 1, wherein the step of comparing occurs in response to the detection of a heart beat occurrence on either of the first and second signals.

12. The method of claim 3, further comprising:

updating a maximum time offset variable after each of the plurality of time offsets is calculated;

comparing the maximum time offset variable to a predetermined threshold; and

generating the one of the coincidence signal and the divergence signal based on this comparison.

13. The method of claim 5, wherein the step of comparing includes incrementing a divergence counter when the jitter is greater than the predetermined jitter value and calculating a coincidence index based on a percentage of divergent cycles to non-divergent cycles.

2. A method of detecting heart beat coincidence, comprising:

receiving first and second signals from first and second heat beat sources, respectively;

detecting first heart beat occurrences on the first signal, each first heart beat occurrence having a respective time associated therewith;

detecting second heart beat occurrences on the second signal, each second heart beat occurrence having a respective time associated therewith;

comparing the times of the first and second heart beat occurrences to detect coincidence including calculating the number of second heart beat occurrences occurring between two first heart beat occurrences; and

generating a divergence signal when a plurality of second heart beat occurrences occur between the two first heart beat occurrences.

6. A method of detecting heat beat coincidence, comprising:

receiving first and second signals from first and second heat beat sources, respectively;

detecting first heart beat occurrences on the first signal, each first heart beat occurrence having a respective time associated therewith;

detecting second heat beat occurrences on the second signal, each second heart beat occurrence having a respective time associated therewith;

comparing the times of the first and second heart beat occurrences to detect coincidence, including;

calculating a plurality of time offsets between the first and second heart beat occurrences;

calculating a jitter between a first time offset and a second time offset;

comparing the jitter to a predetermined jitter value and incrementing a coincidence counter when the jitter is less than a predetermined jitter value;

incrementing a divergence counter when the jitter is greater than the predetermined jitter value; and

calculating a coincidence index based on the ratio of the coincidence counter to the divergence counter; and

generating one of a coincidence signal and a divergence signal based on a plurality of time offsets.

7. The method of claim 6, wherein the step of generating includes generating the coincidence signal when the coincidence index exceeds a predetermined coincidence index value.

8. The method of claim 7, wherein the coincident signal is generated only when the coincidence index exceeds the predetermined coincidence index value for a predetermined time.

9. The method of claim 7, further comprising generating the divergence signal when the coincidence index is less than the predetermined coincidence index value.

10. The method of claim 9, wherein the divergence signal is generated only when the coincidence index is less than the predetermined coincidence index value for a predetermined time.

14. A system for detecting heart beat coincidence, comprising:

means for receiving first and second signals from first and second heart beat sources, respectively;

means for detecting first heart beat occurrences on the first signal, each first heart beat occurrence having a respective time associated therewith;

means for detecting second heart beat occurrences on the second signal, each second heart beat occurrence having a respective time associated therewith; and

means for comparing the times of the first and second heart beat occurrences to detect coincidence including means for calculating a plurality of time offsets between the first and second heat beat occurrences and means for calculating a jitter between a first time offset and a second time offset.

16. The system of claim 14, further comprising means for generating one of a coincidence signal and a divergence signal based on the plurality of time offsets.

17. The system of claim 14, wherein the means for comparing occurs in response to the detection of a heart beat occurrence on either of the first and second signals.

15. A system for detecting heart beat coincidence, comprising:

means for receiving first and second signals from first and second heart beat sources, respectively;

means for detecting first heart beat occurrences on the first signal, each first heart beat occurrence having a respective time associated therewith;

means for detecting second heart beat occurrences on the second signal, each second heart beat occurrence having a respective time associated therewith; and

means for comparing the times of the first and second heart beat occurrences to detect coincidence including means for calculating the number of second heart beat occurrences occurring between two first heart beat occurrences; and

means for generating a divergence signal when a plurality of second heart beat occurrences occur between the two first heart beat occurrences.

18. A heart beat coincidence detection system, comprising:

a processor configured to receive first and second cardiac signals, to detect first and second heart beats on the first and second cardiac signals, respectively, to calculate phase shifts between respective first and second heart beats, and to generate a display signal based on the phase shifts; and

an output device configured to receive the display signal and to provide the display signal to an operator;

wherein the processor is configured to calculate a jitter based on the phase shifts.

19. The heart beat coincidence detection system of claim 18, wherein the processor includes a digital signal processor configured to receive the first and second cardiac signals and to detect the first and second heart beats on the first and second cardiac signals.

20. The heart beat coincidence detection system of claim 18, wherein the output device is a communications link.

21. The heart beat coincidence detection system of claim 18, further comprising an input/output device coupled to the processor configured to receive the first and second cardiac signals and to provide the first and second cardiac signals to the processor.

22. The heart beat coincidence detection system of claim 18, wherein the processor is configured to compare the jitter to a jitter threshold, and to generate the display signal based on the comparison.

23. The heart beat coincidence detection system of claim 18, wherein the processor is configured to calculate a maximum phase shift based on the phase shifts, to compare the maximum phase shift to a maximum phase shift threshold, and to generate the display signal based on the comparison.