Continuous electrocardiogram monitoring method and system for cardiac patients

• US 4,173,971 A
• Filed: 08/29/1977
• Issued: 11/13/1979
• Est. Priority Date: 08/29/1977
• Status: Expired due to Term

• Current Assignee: Allen E. Karz
• Original Assignee: Allen E. Karz
• Inventors: Karz, Allen E.
• Primary Examiner(s): Kamm, William E.
• Application Number:
  US05/828,368
• Time in Patent Office: 806 Days
• Field of Search: 128/2.06 A, 128/2.06 B, 128/2.06 G, 128/2.06 R, 128/2.1 A, 346/33 ME
• US Class Current: 600/515
• CPC Class Codes: A61B 5/0006 ECG or EEG signals
• CPC Class Codes: A61B 5/333 Recording apparatus specially adapted therefor
• CPC Class Codes: A61B 5/337 Playback at speeds other than the recording speed
• CPC Class Codes: A61B 5/338 Recording by printing on paper
• CPC Class Codes: A61B 5/7232 involving compression of the physiological signal, e.g. to extend the signal recording period
• CPC Class Codes: Y10S 128/904 Telephone telemetry

Abstract

A system which is capable of allowing an attending physician to continuously monitor the electrocardiogram (ECG) signals produced by a cardiac patient. The signals, generated by the patient, are first recorded in real time over a predetermined time period established by the physician. At the conclusion of the predetermined time period a monitoring station is automatically alerted by telephone and commences receiving the patient'"'"'s real time ECG signals directly. The recorded ECG signals are then transmitted in a compressed time fashion to the monitoring station simultaneously with the real time ECG signals. The monitoring station receives the compressed time and the real time transmitted signals and following analysis thereof transmits a report of selected portions of the ECG to the physician. Upon instructions from the physician, the monitoring station either returns the recording apparatus to its normal operational status for a predetermined time period, or continues to receive and analyze the real time ECG signal until the patient'"'"'s signal is sufficiently stable and then returns the recording apparatus to its normal operational status. This process repeats continuously. The physician communicates directly with the monitoring station and with the patient as may be required. The system and method provides close and complete monitoring of the patient with complete ECG data retrieval and individualized close patient surveillance.

Claims

1. System for providing cardiac information from a cardiac patient to a remote station comprising:

means for recording electrocardiogram signals produced by the patient in real time at a first predetermined rate;

means for reproducing said recorded signals at a second predetermined rate, said second predetermined rate being greater than said first predetermined rate thereby compressing the time required to reproduce said signals as compared to the time to record said signals;

means for monitoring said reproduced signals;

a communication interface which includes a telephone system having direct dialing capability coupling said reproducing means to said monitoring means;

an automatic telephone dialing means coupled to said telephone system; and

timer means, said timer means activating said automatic dialing means for controlling the periodicity of transmission of recorded signals from said recording means to said monitoring means.

2. A system as defined in claim 1 wherein said means for recording includes a transmitter means for attachment to the patient and receiver means tuned to receive signals transmitted by said transmitter means which signals are representative of electrocardiogram signals from said patient.

3. A system as defined in claim 2 wherein said means for recording further includes modulator means for frequency modulating a carrier having a first frequency responsive to variations in said received signals representative of said electrocardiogram signals.

4. A system as defined in claim 3 wherein said means for recording further includes a magnetic tape recording medium upon which said frequency modulated signals are recorded as said tape moves at a first predetermined speed and are reproduced as said tape moves at a second predetermined speed, said second speed being faster than said first speed.

5. A system as defined in claim 4 wherein said reproducing means includes a demodulator means having a carrier having a second frequency, said second frequency being greater than said first frequency by an amount proportional to the difference between said first and second speeds.

6. A system as defined in claim 1 wherein said timer means includes means for changing the timer at said recording means and at said monitoring means.

7. A system as defined in claim 1 which further includes means for detecting a variation in the repetition rate of said electrocardiogram signals beyond predetermined limits and automatically establishing a communication with said monitoring means responsive thereto.

8. A system as defined in claim 1 which further includes means for detecting a variation in the rhythm of said electrocardiogram signals beyond predetermined limits and automatically establishing a communication with said monitoring means responsive thereto.

9. A system as defined in claim 1 which further includes means for detecting a variation in the repetition rate and the rhythm of said electrocardiogram signals beyond predetermined limits and automatically establishing a communication with said monitoring means responsive thereto.

10. A system as defined in claim 1 which further includes means for detecting a variation in the repetition rate of said electrocardiogram signals beyond predetermined limits and providing an output signal responsive thereto, and means for connecting said output signal to said automatic dialing means for establishing communication with said monitoring means.

11. A system as defined in claim 1 which further includes means for detecting a variation in the rhythm of said electrocardiogram signals beyond predetermined limits and providing an output signal responsive thereto, and means for connecting said output signal to said automatic dialing means for establishing communication with said monitoring means.

12. A system as defined in claim 1 which further includes means for detecting a variation in the repetition rate and the rhythm of said electrocardiogram signals beyond predetermined limits and providing an output signal responsive thereto, and means for connecting said output signal to said automatic dialing means for establishing communication with said monitoring means.

13. A system as defined in claim 1 which further includes means for simultaneously transmitting said electrocardiogram signals in real time to said monitoring means with said reproduced signals.

14. A system as defined in claim 13 which further includes, at said monitoring means, means for making a record of said reproduced and real time electrocardiogram signals.

15. A system as defined in claim 14 wherein said means for making a record is a strip chart recorder.

16. A system as defined in claim 14 which further includes means for communication with a physician including a communication interface with said monitoring means and a communication interface with said patient.

17. A system as defined in claim 16 which further includes means for alerting said patient to communicate verbally with said monitoring means or said physician.

18. A system as defined in claim 1 which further includes indicator means for providing an indication to said patient that said system is producing said signals and providing said signals to said means for monitoring.

19. A system as defined in claim 1 which further includes indicator means for providing an identification of said patient to said monitoring means.

20. A system as defined in claim 1 which further includes means for totalizing said patient'"'"'s heartbeats and transmitting said total to said monitoring means.

21. A system as defined in claim 1 wherein said automatic dialing means, once activated, continues to automatically dial said monitoring means until communication therewith is established.

22. A system as defined in claim 1 which further includes means manually operable by said patient for activating said telephone communication interface thereby to connect said signals to said monitoring means upon demand of said patient.

23. A system as defined in claim 1 wherein said means for monitoring further includes means for generating a confirmation signal responsive to coupling of said reproducing means to said monitoring means and means for transmitting said confirmation signal over said telephone communication interface to said reproducing means, said reproducing means transmitting said signals to said monitoring means only in response to receiving said confirmation signal.

24. A system as defined in claim 1 wherein said means for monitoring includes means for automatically analyzing said signals and displaying appropriate information with respect thereto.

25. Method for providing cardiac information from a cardiac patient to a remote station comprising:

recording the electrocardiogram signals produced by the patient in real time at a first predetermined rate;

reproducing said recorded signals at a second predetermined rate, said second predetermined rate being greater than said first predetermined rate thereby compressing the time required to reproduce said signals as compared to the time to record said signals;

automatically dialing a telephone to connect said reproduced signals to a station remote from said patient;

transmitting said reproduced signals by said telephone to said station remote from said patient;

analyzing said reproduced signals; and

varying the periodicity of transmission of said reproduced signals responsive to said analysis.

26. A method as defined in claim 25 which further comprises the step of simultaneously transmitting the real time electrocardiogram signals along with said reproduced signals on said telephone to said remote station.

27. System for providing cardiac information from a cardiac patient to a remote station comprising:

means for recording electrocardiogram signals produced by the patient in real time at a first predetermined rate;

means for reproducing said recorded signals at a second predetermined rate, said second predetermined rate being greater than said first predetermined rate thereby compressing the time required to reproduce said signals as compared to the time to record said signals;

means for monitoring said reproduced signals;

a communication interface which includes a telephone system having direct dialing capability coupling said reproducing means to said monitoring means;

an automatic telephone dialing means coupled to said telephone system; and

means manually operable by said patient for activating said telephone communication interface thereby to connect said signals to said monitoring means upon demand of said patient.

28. A system as defined in claim 27 wherein said means for recording includes a transmitter means for attachment to the patient and receiver means tuned to receive signals transmitted by said transmitter means which signals are representative of electrocardiogram signals from said patient.

29. A system as defined in claim 28 which further includes means for detecting a variation in the repetition rate and the rhythm of said electrocardiogram signals beyond predetermined limits and automatically establishing, through said telephone, a communication with said monitoring means responsive thereto.

30. A system as defined in claim 27 wherein said means for monitoring includes means for automatically analyzing said signals and displaying appropriate information with respect thereto.

31. A system as defined in claim 27 which further includes means for detecting a variation in the repetition rate and the rhythm of said electrocardiogram signals beyond predetermined limits and automatically establishing, through said telephone, a communication with said monitoring means responsive to occurrence of said variation in either said repetition rate or said rhythm.

32. A system as defined in claim 27 which further includes means for simultaneously transmitting said electrocardiogram signals in real time to said monitoring means with said reproduced signals.

33. A system as defined in claim 32 which further includes, at said monitoring means, means for making a record of said reproduced and real time electrocardiogram signals.

34. A system as defined in claim 33 which further includes means for communication with a physician including a communication interface with said monitoring means and a communication interface with said patient.

35. A system as defined in claim 34 which further includes means for alerting said patient to communicate verbally with said monitoring means or said physician.

36. A system as defined in claim 27 which further includes indicator means for providing an identification of said patient to said monitoring means.

37. A system as defined in claim 27 wherein said automatic dialing means, once activated, continues to automatically dial said monitoring means until communication therewith is established.

38. A system as defined in claim 27 wherein said means for monitoring further includes means for generating a confirmation signal after activation of said communication interface thereby enabling coupling of said reproducing means to said monitoring means and means for transmitting said confirmation signal over said telephone communication interface to said reproducing means, said reproducing means transmitting said signals to said monitoring means in response to receiving said confirmation signal.