Method and improved apparatus for analyzing heart activity

• US 4,628,939 A
• Filed: 11/10/1983
• Issued: 12/16/1986
• Est. Priority Date: 09/11/1980
• Status: Expired due to Term

• Current Assignee: Hughes Electronics Corporation (AT&T, Inc.)
• Original Assignee: Hughes Aircraft Company (Rtx Corporation)
• Inventors: Little, Michael J., Dellamano, Harry A.
• Primary Examiner(s): Howell, Kyle L.
• Assistant Examiner(s): Jaworski, Francis J.
• Application Number:
  US06/550,350
• Time in Patent Office: 1,132 Days
• Field of Search: 128/696, 128/731, 128/708, 128/901, 128/902, 128/908
• US Class Current: 600/509
• 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. Apparatus for producing and displaying an electrical signal indicative of the electrical energy characteristics of the heart, comprising:

(a) a pickup device having pickup electrodes adapted for contact with the skin of a patient and having an output circuit;

(b) an active circuit element coupled between one of said pickup electrodes and said output circuit and being in one state of electrical conduction when said pickup is not in contract with the skin of a patient and being in a different state of electrical conduction when said pickup electrodes are in contact with the skin of a patient;

(c) amplification and display means electrically coupled ot said output circuit for displaying the electical output of said pickup device; and

(d) control means responsive to the state of electrical conduction of said active element when said electrodes are in contact with the skin of a patient for lowering the frequency response of said amplification and display means.

2. Apparatus as set forth in claim 1 in which:

(a) said control means maintains a predetermined low frequency boundary of bandwidth range of said amplification means when said output circuit is in said one state of electical conduction and a lower low frequency boundary of bandwidth range of said amplification means when said output circuit is in said different state of electrical conduction.

3. Apparatus for producing and displaying an electrical signal indicative of the electrical energy characteristics of the heart of a body, comprising:

(a) circuit means including pickup means for producing electrical signals indicative of electrical energy characteristics of the heart and for producing a control signal having a first value when said pickup means is not in contact with the body and a second value when said pickup means is in contact with the body;

(b) amplification means having a controllable bandwidth range and responsive to said electrical signals;

(c) display means responsive to said amplification means for displaying said electrical signals; and

(d) control means responsive to said control signal for controlling the bandwidth range of said amplification means from a first low frequency boundary when said pickup means is not in contact with the body to a lower low frequency boundary when said pickup means is in contact with the body.

4. Apparatus as set forth in claim 3, in which:

(a) the first low frequency boundary of bandwidth range is about 5 Hz/sec. when said pickup means is not in contact with the body and the lower low frequency boundary of bandwidth range is about 0.05 Hz/sec. when said pickup means is in contact with the body.