Portable heart monitor performing multiple functions

• US 4,974,601 A
• Filed: 09/05/1988
• Issued: 12/04/1990
• Est. Priority Date: 09/05/1988
• Status: Expired due to Term

• Current Assignee: University of South Carolina
• Original Assignee: University of North Carolina At Charlotte (University of North Carolina System)
• Inventors: Said, Mohammed, Sandok, Paul, Vadhar, Bharati, Tranjan, Farid M.
• Primary Examiner(s): Jaworski, Francis
• Assistant Examiner(s): MANUEL, GEORGE C
• Application Number:
  US07/244,964
• Time in Patent Office: 820 Days
• Field of Search: 128/695, 128/696, 128/700, 128/702, 128/706, 128/708, 128/680
• US Class Current: 600/509
• CPC Class Codes: A61B 5/02438 with portable devices, e.g. worn by the patient
• CPC Class Codes: A61B 5/335 using integrated circuit memory devices

Abstract

A method and apparatus for monitoring multiple aspects of a patient'"'"'s cardiac condition which is portable microprocessor based, and can be programmed to select (for storage in random access memory (RAM)) anomalous heartbeat waveforms while rejecting normal waveforms. In addition, the cardiac monitor gives real time warnings of erratic heartbeat waveforms and stores these waveforms for future analysis. The cardiac monitor also detects and energizes an alarm signal if a patient'"'"'s heartbeat skips a predetermined number of beats.

Claims

1. An apparatus for monitoring multiple aspects of a patient'"'"'s cardiac condition comprising:

(a) means for generating a present pulse signal indicative of a patient'"'"'s present pulse rate and a present heartbeat waveform signal;

(b) means for receiving the present pulse signal and generating an average pulse rate signal indicative of the pulse rate over a predetermined period of time;

(c) means for storing the average pulse rate signal;

(d) means for comparing the present pulse signal and the average pulse rate signal and generating an alarm signal if the difference between these signals exceeds a first predetermined threshold;

(e) means for receiving the present heartbeat waveform signal and generating an average heartbeat waveform signal indicative of the patient'"'"'s average heartbeat over a predetermined period of time;

(f) means for storing the average heartbeat waveform signal;

(g) means for comparing the present heartbeat waveform signal and the average heartbeat waveform signal and generating an alarm signal if the difference between these signals exceeds a second predetermined threshold; and

(h) means for storing the present heartbeat waveform signal indicative of the patient'"'"'s present heartbeat that resulted in the generation of an alarm signal.

2. The apparatus of claim 1 wherein the means for generating a present signal indicative of a patient s present pulse rate and a present heartbeat waveform signal comprises:

means for sensing a patient'"'"'s heartbeat and generating a signal representing the patient'"'"'s heartbeat;

means for storing the signal representing the patient'"'"'s heartbeat;

means for storing the signal representing the patient'"'"'s heartbeat;

means for generating the heartbeat waveform signal from the stored heartbeat signal and;

means for calculating a pulse rate from the stored heartbeat signal.

3. The apparatus of claim 1 wherein the means for receiving the present pulse signal and generating an average pulse rate signal comprises:

means for storing the present pulse signal and generating an average pulse rate signal therefrom.

4. The apparatus of claim 1 wherein the apparatus further comprises:

means for displaying a representation of the present pulse signal indicating the present pulse rate.

5. The apparatus of claim 1 wherein the means for generating an average heartbeat waveform comprises:

means for storing a plurality of present heartbeat waveform signals and generating an average electric heartbeat waveform signal therefrom.

6. The apparatus of claim 1 wherein the means for generating a present pulse signal indicative of a patient'"'"'s present pulse rate and present heartbeat waveform comprises:

a transducer for generating an analog signal representative of a patient'"'"'s present heartbeat;

means for amplifying the analog signal; and

means for converting the amplified analog signal to a digital signal.

7. The apparatus of claim 1 wherein the means for receiving the present pulse signal and generating an average pulse rate signal indicative of the patient'"'"'s pulse rate comprises:

means for converting heartbeat signals into a square waveform signal; and

means for calculating a pulse rate from a square waveform signal.

8. A method for monitoring multiple aspects of a patient'"'"'s cardiac condition comprising:

(a) generating a present pulse signal indicative of a patient'"'"'s current pulse rate and a present heartbeat waveform signal;

(b) generating an average pulse rate signal indicative of the patient'"'"'s pulse rate over a predetermined period of time;

(c) storing the average present pulse rate signal;

(d) comparing the present pulse signal and the average pulse rate signal and generating an alarm signal if the difference between these signals exceeds a first predetermined threshold;

(e) receiving the present heartbeat waveform signal and generating an average heartbeat waveform signal indicative of the patient'"'"'s average heartbeat over a predetermined period of time;

(f) storing the average heartbeat waveform signal;

(g) comparing the present heartbeat waveform signal and the average heartbeat waveform signal and generating an alarm signal if the difference between these signals exceeds a second predetermined threshold; and

(h) storing the present heartbeat waveform signal indicative of the patient'"'"'s current heartbeat that resulted in the generation of an alarm signal.

9. The method of claim 8 further comprising:

displaying a numerical representation of the present pulse signal indicating the present pulse rate.

10. The method of claim 8 wherein the step of generating an average pulse rate signal comprises:

storing the present heartbeat waveform signals and generating the average pulse rate signal therefrom.

11. The method of claim 8 wherein the step of generating an average heartbeat waveform comprises:

storing the present heartbeat waveform signals and generating an average electric heartbeat waveform signal therefrom over a predetermined period of time.

12. The method of claim 8 wherein the step of generating a present pulse signal indicative of a patient'"'"'s current pulse rate and a present heartbeat waveform comprises:

sensing the patient'"'"'s heartbeat and generating a heartbeat signal;

storing the heartbeat signals;

generating a heartbeat waveform from the stored heartbeat signals; and

calculating a pulse rate from the stored heartbeat signals.

13. The method of claim 8 wherein the step of receiving the present pulse signal and generating an average pulse rate signal comprises:

storing the present pulse signal and generating an average pulse rate signal therefrom.