Method and improved apparatus for analyzing activity

• US 4,428,380 A
• Filed: 09/11/1980
• Issued: 01/31/1984
• Est. Priority Date: 09/11/1980
• Status: Expired due to Term

• Current Assignee: Hughes Electronics Corporation (Rtx Corporation)
• Original Assignee: Hughes Aircraft Company (Rtx Corporation)
• Inventors: Little, Michael J., Calderone, Theodore, Margerum, J. David, Dellamano, Harry A., Wong, Shi-Yin, Nussmeier, Thomas A.
• Primary Examiner(s): Howell, Kyle L.
• Assistant Examiner(s): Jaworski, Francis J.
• Application Number:
  US06/186,041
• Time in Patent Office: 1,237 Days
• Field of Search: 128/715, 128/700, 128/773, 128/680-681, 179/1 ST
• US Class Current: 600/528
• CPC Class Codes: A61B 5/332 Portable devices specially adapted therefor
• CPC Class Codes: A61B 5/339 Displays specially adapted therefor
• CPC Class Codes: A61B 7/00 Instruments for auscultation

Abstract

A method and associated means for producing simultaneous electrical representations of the electrical and acoustical (heart sound) activity of the heart, in which a pickup device and associated circuits produce a full wave rectified symmetrical heart sound signal annotated by pulses developed from the QRS wave of the electrocardiogram signal.

The pickup device is designed to permit the direct (unbuffered) application of the pickup electrodes to the skin of the body and to provide a control of the associated circuits when not in contact with the body to shorten response times when the pickup device is placed in contact with the body.

Claims

1. A method for producing a visual representation of the activity of a heart comprising the steps of:

(a) generating a first analog electrical signal and a second analog electrical signal, said first signal representing the electrocardiogram (ECG) of the heart and said second signal representing the heart sounds;

(b) deriving an annotation signal from said first signal, said annotation signal representing the location of the QRS complex of said ECG;

(c) rectifying said second signal;

(d) combining said annotation signal with said rectified second signal to produce an annotated recitifed heart sound signal;

(e) utilizing said annotated rectified signal to produce a symmetrical annotated rectified signal; and

(f) displaying at least said symmetrical annotated rectified signal so that the heart'"'"'s audio characteristics may be observed.

2. The method of claim 1 in which said second signal is full wave rectified.

3. The method of claim 1 in which said first signal is also displayed.

4. A method as defined in claim 3 characterized by the additional steps of:

(a) applying said first signal and said annotated rectified heart sound signal to digital processing circuitry; and

(b) controlling said digital processing circuitry so that alternate data and modes may be displayed, said data including segments and multiples of the heart cycle and said modes including continuous and freeze frame modes.

5. A method as defined in claim 3 additionally characterized by the step of normalizing said first signal and said second signal for full utilization of said display means.

6. The method of claim 1 in which said first signal and said symmetrical annotated rectified signal are selectively displayed.

7. A method for producing an electrical signal indicative of the sounds of a heart comprising the steps of:

(a) utilizing the electrical energy and the sound energy of the heart to produce a rectified annotated heart sound signal; and

(b) utilizing said rectified annotated signal to produce a symmetrical annotated heart sound signal.

8. Apparatus for producing an electrical signal indicative of the sounds of a heart comprising:

(a) means including a pickup device responsive to the electrical energy and the acoustical energy of the heart for producing first and second electrical signals, respectively;

(b) means for deriving an annotation signal from said first electrical signal;

(c) means responsive to said annotation signal and said second electrical signal for producing a rectified annotated signal; and

(d) means responsive to said rectified annotated signal for producing a symmetrical heart sound signal.

9. Apparatus for producing an electrical signal indicative of the sounds of a heart comprising:

(a) means including a pickup device responsive to the electrical energy and the acoustical energy of the heart for producing a rectified annotated heart sound signal; and

(b) means responsive to said recitified annotated signal for producing a symmetrical annotated heart sound signal.

10. Apparatus for producing a visual display of the electrical and acoustical activity of a heart comprising:

(a) a pickup device for transforming the heart'"'"'s electrical (ECG) and acoustical energy into a first analog electrical signal and a second analog electrical signal, respectively;

(b) means for deriving an annotation signal from said first analog electrical signal;

(c) means for combining said annotation signal with said second analog signal to produce an annotated heart sound signal (EAHS);

(d) digital processing circuitry for deriving both continuous and freeze frame data modes from said ECG and EAHS signals; and

(e) means for displaying at least said annotated heart sound signal in one of said data modes.

11. Apparatus for producing a visual display of the electrical and acoustical activity of a heart comprising:

(a) a pickup device for transforming the heart'"'"'s electrical (ECG) and acoustical energy into a first analog electrical signal and a second analog electrical signal, respectively;

(b) means for deriving an annotation signal from said first analog electrical signal;

(c) means for combining said annotation signal with said second analog signal to produce an annotated heart sound signal (EAHS);

(d) digital processing circuitry for deriving both continuous and freeze frame data modes from said ECG and EAHS signals;

(e) means for selecting one of the ECG and EAHS signal and the data mode thereof; and

(f) means for displaying the selected signal and data mode.

12. Apparatus as defined in claim 11 wherein said means for combining said annotation signal with said second analog signal additionally includes:

(a) means for producing a pulsed signal, the pulses of which coincide in time with the QRS complex of the ECG;

(b) a rectifier for converting said heart sound data to a unipolar signal;

(c) means for combining said pulsed signal with said unipolar signal to produce a rectified, annotated heart sound signal;

(d) means for inverting said rectified annotated heart sound signal; and

(e) means for displaying said rectified, annotated heart sound signal rapidly with said inverted signal to produce a symmetrical annotated heart sound signal (EAHS).

13. Apparatus as defined in claim 11 wherein said means for combining said annotation signal with said second analog signal additionally includes:

(a) means for producing a pulsed signal, the pulses of which coincide in time with the QRS complex of the ECG;

(b) a rectifier for converting said heart sound data to a unipolar signal;

(c) means for combining said pulsed signal with said unipolar signal to produce a rectified, annotated heart sound signal;

(d) means for inverting said rectified annotated heart sound signal;

(e) means for displaying said recitified annotated heart sound signal rapidly with said inverted signal to produce an annotated heart sound signal which is symmetrical about a base line; and

(f) means for resetting said base line in a predetermined time period including one display period to maintain said symmetrical signal in a predetermined position on said means for displaying.

14. A method for producing an electrical signal indicative of the sounds of a heart comprising the steps of:

(a) utilizing the electrical energy and the sound energy of the heart to produce a rectified annotated heart sound signal;

(b) utilizing said rectified, annotated signal to produce an inverted, rectified, annotated signal; and

(c) displaying said rectified, annotated signal with said inverted, rectified, annotated signal, symmetrically about a base line to produce a symmetrical, rectified, annotated signal.

15. Apparatus for producing an electrical signal indicative of the sounds of a heart comprising:

(a) means including a pickup device responsive to the electrical energy and the acoustical energy of the heart for producing a rectified annotated heart sound signal;

(b) means responsive to said rectified, annotated signal for producing an inverted, rectified, annotated signal; and

(c) means for displaying said rectified, annotated signal with said inverted, rectified annotated signal, symmetrically about a base line, to produce a symmetrical annotated heart sound signal.

16. Apparatus for producing an electrical signal indicative of the sounds of a heart comprising:

(a) means including a pickup device responsive to the electrical energy and the acoustical energy of the heart for producing a rectified annotated heart sound signal;

(b) means responsive to said rectified, annotated signal for producing an inverted, rectified, annotated signal;

(c) an oscillator;

(d) a cathode ray tube; and

(e) circuits responsive to said oscillator for sequentially coupling said rectified, annotated signal and said inverted, rectified, annotated signal to said cathode ray tube for display symmetrically about a base line, to produce a symmetrical, annotated heart sound signal.