System for cardiac arrhythmia detection and characterization

• US 8,233,972 B2
• Filed: 10/07/2010
• Issued: 07/31/2012
• Est. Priority Date: 02/12/2010
• Status: Active Grant

• Current Assignee: PixArt Imaging Incorporated
• Original Assignee: Siemens Medical Solutions USA Incorporated (Siemens AG)
• Inventors: Zhang, Hongxuan
• Primary Examiner(s): Manuel, George
• Application Number:
  US12/899,613
• Publication Number:
  US 20110201951A1
• Time in Patent Office: 663 Days
• Field of Search: 600/509
• US Class Current: 600/509
• CPC Class Codes: A61B 5/021 Measuring pressure in heart or blood vessels A61B5/0205 takes precedence
• CPC Class Codes: A61B 5/026 Measuring blood flow A61B3/1233, A61B3/1241 take precedence
• CPC Class Codes: A61B 5/14551 for measuring blood gases
• CPC Class Codes: A61B 5/349 Detecting specific parameters of the electrocardiograph cycle
• CPC Class Codes: A61B 5/352 Detecting R peaks, e.g. for synchronising diagnostic apparatus; Estimating R-R interval

Abstract

A system for heart performance characterization and abnormality detection includes an interface that receives a signal representing electrical activity of a patient heart occurring during individual heart cycles of multiple sequential heart cycles. A signal processor decomposes the received signal into multiple signals comprising a heart cycle signal primary wave and one or more heart cycle signal wavelets occurring at corresponding successively higher frequencies. The signal processor determines multiple amplitude representative values of the heart cycle signal primary wave and the one or more heart cycle signal wavelets. A comparator compares the multiple amplitude representative values with corresponding multiple predetermined threshold values to provide comparison indicators. A patient monitor in response to the comparison indicators indicating at least one of the amplitude representative values exceeds a respective predetermined threshold value, generates an alert message associated with the respective predetermined threshold.

Claims

1. A system for heart performance characterization and abnormality detection, comprising:

an interface for receiving a signal representing electrical activity of a patient heart occurring during individual heart cycles of a plurality of sequential heart cycles;

a signal processor for,

decomposing the received signal into a plurality of signals comprising a heart cycle signal primary wave and one or more heart cycle signal wavelets occurring at corresponding successively higher frequencies and

determining a plurality of amplitude representative values of said heart cycle signal primary wave and said one or more heart cycle signal wavelets;

a comparator for comparing said plurality of amplitude representative values with a corresponding plurality of predetermined threshold values; and

a patient monitor for in response to the comparison indicating at least one of said amplitude representative values exceeds a respective predetermined threshold value, generating an alert message associated with the respective predetermined threshold.

2. A system according to claim 1, wherein

said plurality of sequential heart cycles are successive heart cycles.

3. A system according to claim 1, wherein

said amplitude representative values of said heart cycle signal primary wave and said one or more heart cycle signal wavelets comprise at least one of (a) a peak amplitude, (b) a mean amplitude value, (c) a median amplitude value and (d) a root mean square amplitude value.

4. A system according to claim 1, wherein

said signal processor measures said plurality of amplitude representative values.

5. A system according to claim 1, wherein

said signal representing electrical activity of a patient heart comprises digitized sampled data values.

6. A system according to claim 1, wherein

said signal processor filters the received signal and segments the filtered received signal into heart cycle segments comprising an ST segment.

7. A system according to claim 1, wherein

said signal processor decomposes the received signal into a plurality of signals comprising a heart cycle signal primary wave and one or more heart cycle signal wavelets substantially occurring at harmonic frequencies of the primary wave.

8. A system according to claim 1, wherein

said one or more heart cycle signal wavelets comprise Fourier components of the primary wave.

9. A system according to claim 1, wherein

said successively higher frequencies comprise at least one of, (a) harmonics of the primary wave, (b) half-harmonics of the primary wave and (c) intermediate frequencies between harmonics of the primary wave.

10. A system according to claim 1, wherein

said comparator determines a comparison indicator indicating at least one of said amplitude representative values lies in a predetermined value range and

said patient monitor, in response to said comparison indicator indicating at least one of said amplitude representative values lies in a predetermined value range, generates an alert message associated with the value range.

11. A system according to claim 1, wherein

at least one of said predetermined threshold values is derived from recorded patient heart electrical activity signals for said patient.

12. A system according to claim 1, wherein

at least one of said predetermined threshold values is derived from recorded patient heart electrical activity signals for a population of patients having similar demographic characteristics including at least two of (a) age, (b) weight, (c) gender and (d) height, to those of said patient.

13. A system according to claim 1, wherein

said signal processor dynamically adjusts at least one of said predetermined threshold values in response to a determined heart electrical activity signal variation of said patient.

14. A system according to claim 1, including

a repository of mapping information, associating ranges of said amplitude representative values with corresponding medical conditions and

said comparator compares said amplitude representative values with said ranges to provide a comparison indicator identifying a medical condition and

said patient monitor generates an alert message identifying said medical condition.

15. A system according to claim 14, wherein

said predetermined mapping information associates ranges of said amplitude representative values with particular patient demographic characteristics and with corresponding medical conditions and said system uses patient demographic data including at least one of, age weight, gender and height in comparing the ratio with said ranges and generating an alert message indicating a potential medical condition.

16. A method for heart performance characterization and abnormality detection, comprising the activities of:

receiving a signal representing electrical activity of a patient heart occurring during individual heart cycles of a plurality of sequential heart cycles;

decomposing the received signal into a plurality of signals comprising a heart cycle signal primary wave and one or more heart cycle signal wavelets occurring at corresponding successively higher frequencies;

determining a plurality of amplitude representative values of said heart cycle signal primary wave and said one or more heart cycle signal wavelets;

comparing said plurality of amplitude representative values with a corresponding plurality of predetermined threshold values; and

in response to the comparison indicating at least one of said amplitude representative values exceeds a respective predetermined threshold value, generating an alert message associated with the respective predetermined threshold.

17. A method according to claim 16, including

associating ranges of said amplitude representative values with corresponding medical conditions and

comparing said amplitude representative values with said ranges to identify a medical condition.

18. A system for heart performance characterization and abnormality detection, comprising:

an interface for receiving a signal representing electrical activity of a patient heart occurring during individual heart cycles of a plurality of sequential heart cycles;

a signal processor for,

decomposing the received signal into a plurality of signals comprising a heart cycle signal primary wave and one or more heart cycle signal wavelets occurring at corresponding successively higher frequencies and

determining a plurality of amplitude representative values of said heart cycle signal primary wave and said one or more heart cycle signal wavelets;

a repository of mapping information, associating predetermined thresholds of said amplitude representative values with corresponding medical conditions; and

a patient monitor for comparing said amplitude representative values with said predetermined thresholds to identify a medical condition.

19. A system according to claim 18, wherein

said signal processor decomposes the received signal into a plurality of signals comprising a heart cycle signal primary wave and one or more heart cycle signal wavelets substantially occurring at harmonic frequencies of the primary wave.