Memory loop ECG recorder with continuous recording

• US 20010039385A1
• Filed: 02/07/2001
• Published: 11/08/2001
• Est. Priority Date: 05/10/2000
• Status: Active Grant

• Current Assignee: Lohmann Technologies
• Original Assignee: Cardiac Evaluation Center, Inc. (SHL Telemedicine Ltd.)
• Inventors: Ellenz, John D.
• Granted Patent: US 6,438,412 B2
• Time in Patent Office: Days
• US Class Current: 600/524
• CPC Class Codes: A61B 5/0006 ECG or EEG signals
• CPC Class Codes: A61B 5/335 using integrated circuit memory devices
• CPC Class Codes: A61B 5/349 Detecting specific parameters of the electrocardiograph cycle

Abstract

An ECG recorder is provided that includes a processor configured to perform the ECG data sampling routine while performing additional routines, such as transmitting stored ECG events and setting user preferences. Accordingly, a patient'"'"'s ECG signal is continuously sampled at all times during operation of the recorder.

Claims

1. An apparatus for recording electrocardiographic data from a patient, comprising:

an acquisition circuit operable to receive at least one electrocardiographic signal having a time-varying amplitude from the patient at a plurality of instants in time to produce samples and further digitizing the samples of the electrocardiographic signal to indicate the amplitude of the electrocardiographic signal at the plurality of instants to produce digitized samples;

at least one memory operable to receive and store the digitized samples according to their associated sampling instants in time; and

a processor communicating with the acquisition circuit and the memory to transfer the digitized samples from the acquisition circuit to the memory as a first task while executing a second task on a functionally concurrent basis, wherein the second task is selected from the group consisting of transmitting electrocardiographic data and setting user preferences.

2. The apparatus as recited in

claim 1

, wherein the processor receives an interrupt at a frequency greater than the frequency at which the electrocardiographic data is sampled, and wherein the interrupt causes the processor to sample the electrocardiographic signal.

3. The apparatus as recited in

claim 1

, wherein the processor operates to continue to sample the electrocardiographic signal immediately after the data has been transmitted.

4. The apparatus as recited in

claim 2

, wherein the electrocardiographic signal is sampled at approximately 120 hertz, and the interrupt occurs at a frequency of approximately 480 hertz.

5. The apparatus as recited in

claim 1

, wherein an electrocardiographic event is detected and stored in the memory with the digitized samples so as to indicate relative ordering of the electrocardiographic event and the digitized samples.

6. The apparatus as recited in

claim 1

, wherein the second task comprises storing electrocardiographic data for future transmission.

7. The apparatus as recited in

claim 6

, wherein electrocardiographic data is stored in response to a manual input indicating an abnormal electrocardiographic event.

8. The apparatus as recited in

claim 6

, wherein the electrocardiographic data is stored in response to an automatic detection of an abnormal electrocardiographic event.

9. An apparatus for recording electrocardiographic data from a patient, comprising:

an acquisition circuit operable to receive at least one electrocardiographic signal having a time-varying amplitude from the patient at a plurality of instants in time to produce samples and further digitizing the samples of the electrocardiographic signal to indicate the amplitude of the electrocardiographic signal at the plurality of instants to produce digitized samples;

at least one memory operable to receive and store the digitized samples according to their associated sampling instants in time; and

a processor communicating with the acquisition circuit and the memory to transfer the digitized samples from the acquisition circuit to the memory as a first task while executing a second task on a functionally concurrent basis, wherein the second task comprises operating at all points in time between the transmission of electrocardiographic data and erasure of the stored digitized samples.

10. A method for monitoring and transmitting electrocardiographic data from a patient to a remote display terminal, the steps comprising:

(a) receiving at least one electrocardiographic signal having a time-varying amplitude from the patient and transferring the signal to the apparatus;

(b) producing samples of the electrocardiographic signal at a plurality of instants;

(c) digitizing the samples to indicate the amplitude of the electrocardiographic signal at the plurality of instants;

(d) storing the digitized samples according to their associated sampling instants in time; and

(e) performing at least one operation sequence on a functionally concurrent basis with step (d).

11. The method as recited in

claim 10

, further comprising detecting at least one cardiac abnormality and storing electrocardiographic data corresponding to the abnormality.

12. The method as recited in

claim 11

, wherein the at least one operation sequence includes one of the group consisting of transmitting the stored electrocardiographic data and setting at least one user preference.