System for the diagnosis and monitoring of coronary artery disease, acute coronary syndromes, cardiomyopathy and other cardiac conditions

• US 20040039292A1
• Filed: 03/26/2003
• Published: 02/26/2004
• Est. Priority Date: 03/26/2002
• Status: Active Grant

• Current Assignee: National Aeronautics and Space Administration US Government As Represented By The Administrator of The
• Original Assignee: National Aeronautics and Space Administration US Government As Represented By The Administrator of The
• Inventors: Arenare, Brian, Schlegel, Todd T.
• Granted Patent: US 7,386,340 B2
• Time in Patent Office: Days
• US Class Current: 600/509
• CPC Class Codes: A61B 5/366 Detecting abnormal QRS complex, e.g. widening

Abstract

Cardiac electrical data are received from a patient, manipulated to determine various useful aspects of the ECG signal, and displayed and stored in a useful form using a computer. The computer monitor displays various useful information, and in particular graphically displays various permutations of reduced amplitude zones and kurtosis that increase the rapidity and accuracy of cardiac diagnoses. New criteria for reduced amplitude zones are defined that enhance the sensitivity and specificity for detecting cardiac abnormalities.

Claims

1. An electrocardiograph system comprising:

a. means for sensing a plurality of electrocardiograph signals from a patient, the signals comprising cardiac data;

b. means for isolating the QRS interval in each of the plurality of signals;

c. means for detecting a reduced amplitude zone within the QRS interval in each of the plurality of signals relating to cardiac function of a patient, the reduced amplitude zone within the QRS interval comprising RAZ data;

d. means for relating at least two of the detected reduced amplitude zones in accordance with predetermined criteria to develop cardiac diagnoses; and

e. means for displaying the cardiac data and the RAZ data in real-time on a monitor.

2. The system of claim 1, wherein the reduced amplitude zone is defined as a region of the QRS interval lying between two neighboring maxima or minima.

3. The system of claim 1, wherein the reduced amplitude zone is defined as a region of the QRS interval lying between two neighboring maxima or minima, and wherein a second, smaller local maximum within the QRS interval is at least a certain user-selectable percentage of the larger of the maxima or minima.

4. The system of claim 3, wherein the percentage is any percentage between 0% and 100%.

5. The system of claim 1, wherein the reduced amplitude zone is defined as a region of the QRS interval lying between two neighboring maxima or minima, and wherein the voltage of a second, smaller local maximum within the QRS interval is at least a certain user-selectable percentage of that of the larger of the maxima, and wherein the voltage of a second, smaller, local minimum within the QRS interval is at least a certain user-selectable percentage of that of the larger of the minima.

6. The system of claim 1, further comprising means for analyzing kurtosis in the QRS interval and determining kurtosis below a predetermined minimum.

7. The system of claim 1, wherein the means for sensing a plurality of electrocardiograph signals comprise a plurality of electrodes, and wherein the electrodes are defined in spatial relation to one another.

8. The system of claim 7, wherein the means for relating at least two of the detected reduced amplitude zones, relate the reduced amplitude zones in terms of spatial relation.

9. The system of claim 7, wherein the means for relating includes means for relating all of the detected reduced amplitude zones from the means for detecting.

10. The system of claim 1, further comprising means for recording a first set of baseline cardiac and RAZ data, and further comprising means for comparing the first set of baseline cardiac and RAZ data with cardiac and RAZ data captured in real time.

11. The system of claim 10, wherein the means for displaying the cardiac data and the RAZ data in real-time on a monitor includes means for displaying the first set of baseline cardiac and RAZ data along with cardiac and RAZ data captured in real time.

12. The system of claim 1, wherein the means for sensing a plurality of electrocardiograph signals includes CR precordial leads.

13. The system of claim 1, further comprising:

a. means for developing a time-varying template of cardiac data from each of the means of sensing; and

b. means for cross-correlating cardiac data in real time from each of the means of sensing with a respective time-varying template.

14. The system of claim 5, further comprising means indicating likely coronary artery disease, acute coronary syndrome, or other cardiac condition when a reduced amplitude zone is present in each of three or more spatially contiguous sensing means.

15. The system of claim 3, further comprising means indicating likely coronary artery disease, acute coronary syndrome, or other cardiac condition when a reduced amplitude zone is present in each of four or more spatially contiguous sensing means.

16. The system of claim 3, further comprising means indicating likely coronary artery disease, acute coronary syndrome, or other cardiac condition when a reduced amplitude zone is present in each of five or more sensing means in a predetermined distribution.

17. An electrocardiograph system comprising:

a. a plurality of electrodes adapted to be attached to a patient, each of the plurality of electrodes providing an electrocardiogram signal comprising a plurality of heartbeats, the electrocardiogram signal including a QRS interval;

b. an electrocardiogram console adapted to receive the electrocardiogram signals from the electrodes and to sample the electrocardiogram signals at at least the Nyquist rate;

c. a computer coupled to the console to receive the sampled electrocardiogram and to filter the high frequency components from the sampled electrocardiogram, the computer detecting a reduced amplitude zone within the QRS interval in each of the plurality of signals and relating at least two of the detected reduced amplitude zones in accordance with predetermined criteria to formulate cardiac diagnoses; and

d. a monitor to display the cardiac data in real time.

18. The system of claim 17, wherein the reduced amplitude zone is defined as a region of the QRS interval lying between two neighboring maxima or minima.

19. The system of claim 17, wherein the reduced amplitude zone is defined as a region of the QRS interval lying between two neighboring maxima or minima, and wherein a second, smaller local maximum within the QRS interval is at least a certain user-selectable percentage of the larger of the maxima or minima.

20. The system of claim 19, wherein the percentage is any percentage between 0% and 100%.

21. The system of claim 20, wherein the reduced amplitude zone is defined as a region of the QRS interval lying between two neighboring maxima or minima, and wherein the voltage of a second, smaller local maximum within the QRS interval is at least a certain user-selectable percentage of that of the larger of the maxima, and wherein the voltage of a second, smaller local minimum within the QRS interval is at least a certain user-selectable percentage of that of the larger of the minima.

22. A display for the display of electrocardiographic data comprising:

a. a plot of at least one real-time low frequency electrocardiogram signal; and

b. a plot of at least one real-time high frequency electrocardiogram signal derived from the at least one real-time low frequency electrocardiogram signal, the plot of the at least one real-time low frequency electrocardiogram signal displayed adjacent the plot of the at least one real-time high frequency electrocardiogram signal.