Portable cardiac monitor

• US 20060229521A1
• Filed: 04/08/2005
• Published: 10/12/2006
• Est. Priority Date: 04/08/2005
• Status: Active Grant

• Current Assignee: Exelys LLC
• Original Assignee: Exelys LLC
• Inventors: Barr, Keith E.
• Granted Patent: US 7,361,188 B2
• Time in Patent Office: Days
• US Class Current: 600/509
• CPC Class Codes: A61B 5/0006 ECG or EEG signals
• CPC Class Codes: A61B 5/332 Portable devices specially adapted therefor
• CPC Class Codes: A61B 5/335 using integrated circuit memory devices

Abstract

A system and method for obtaining ECG signals from an ambulatory patient are disclosed herein. The system is configured to be inexpensive, small, and robust for outpatient monitoring. The system is configured to be a low power consuming device. The system provides options for a variety of settings and real-time access to the ECG signals being recorded during the recording period.

Claims

1. An ambulatory electrocardiogram (ECG) monitor, comprising:

a recorder module configured to attach to an ambulatory patient during a recording period, wherein the recorder module is calibrated via a base station or a computer, the data being recorded is assessable in real-time via a radio frequency (RF) link with the base station, and the ambulatory patient can annotate the data being recorded in real-time by interfacing with an annotator included on the exterior of the recorder module.

2. The monitor of claim 1, wherein the annotator comprises an annotate button for access by a health care professional or the ambulatory patient.

3. The monitor of claim 1, wherein the average current consumption of the recorder module is less than 1 milliamp.

4. The monitor of claim 1, wherein the recorder module includes a converter circuitry, a microcontroller circuitry, and a flash memory circuitry.

5. The monitor of claim 4, wherein the converter circuitry includes a FIFO memory.

6. The monitor of claim 5, wherein the microcontroller circuitry and the flash memory circuitry are turned on for a time duration sufficient to transfer data from the FIFO memory to the flash memory circuitry.

7. The monitor of claim 5, wherein the microcontroller circuitry and the flash memory circuitry are powered when the FIFO memory is at near maximum capacity.

8. The monitor of claim 1, further comprising a moisture resistant sealer over at least one cover encapsulating the recorder module.

9. The monitor of claim 8, further comprising an another cover, wherein the another cover and the at least one cover encase the recorder module and form an equatorial seam where the another cover and the at least one cover contacts each other.

10. A method for monitoring electrocardiogram (ECG) waveforms from an ambulatory patient, the method comprising:

receiving cardiac electrical potential signals from the ambulatory patient;

receiving additional patient data during the recording period, in response to actuation of an annotation device by the ambulatory patient;

converting the cardiac electrical potential signals into digital signals;

storing the digital signals and the additional patient data;

wirelessly transmitting the digital signals and the additional patient data during the recording period; and

outputting the stored digital signals and the additional patient data for analysis.

11. The method of claim 10, further comprising:

calibrating prior to the recording period.

12. The method of claim 11, wherein calibrating includes at least one of erasing possible stored data, selecting a clip detection feature, and storing patient identifying information.

13. The method of claim 10, comprising specifying a sampling rate selected from a group including 128 Hz, 256 Hz, 512 Hz, and 1024 Hz.

14. The method of claim 10, wherein the additional patient data is indicative of a flag to the cardiac electrical potential signals received contemporaneous to the actuation of the notation device.

15. The method of claim 10, comprising intermittently powering a long term memory device and transferring the stored digital signals and the additional patient data.

16. The method of claim 10, wherein wirelessly transmitting includes radio frequency (RF) transmission with a range of less than approximately 12 inches.

17. Circuitry for obtaining electrocardiogram (ECG) signals associated with an ambulatory patient, the circuitry comprising:

a first integrated circuit (IC) configured to accept differential channels of ECG signals, process the ECG signals, and store the processed ECG signals;

a second IC in communication with the first IC, the second IC including a microcontroller; and

a third IC in communication with the second IC, the third IC configured to store the processed ECG signals from the first IC,

wherein each of the second and third ICs is selectively powered in response to an approximately full capacity of the stored processed ECG signals in the first IC.

18. The circuitry of claim 17, wherein the first, second, and third ICs are provided in a recorder module weighing less than approximately 16 grams.

19. The circuitry of claim 17, further comprising:

capacitors coupled to the first IC to correct out-of-range ECG signals.

20. The circuitry of claim 17, further comprising:

a notation switch coupled to the first IC, wherein the stored processed ECG signals include data associated with a condition of the notation switch.

21. The circuitry of claim 17, further comprising:

an antenna coupled to the first IC, wherein the first IC includes a radio frequency (RF) modulator and the antenna transmits the processed ECG signals in real-time.

22. The circuitry of claim 17, wherein the stored processed ECG signals include data associated with each of the differential channels, a condition of a notation switch, and an error check.

23. The circuitry of claim 17, wherein the first IC includes a clip detector.

24. The circuitry of claim 17, wherein the second IC shuts off power to the first, second, and third ICs when the third IC has reached full storage capacity.

25. A portable cardiac recorder, comprising:

means for analog-to-digital converting cardiac signals from a patient;

means for correcting the cardiac signals that are out-of-range;

means for annotating certain of the converted cardiac signals in real-time;

means for radio frequency (RF) transmitting the converted cardiac signals; and

means for storing the converted cardiac signals.

26. The portable cardiac recorder of claim 25, wherein the recorder weighs less than approximately 28 grams.

27. The portable cardiac recorder of claim 25, comprising means for moisture proofing the recorder, the means for moisture proofing including a moisture resistant sealer applied over a seam formed by an encasing cover.

28. The portable cardiac recorder of claim 25, comprising at least one disposable component selected from a group including electrodes, batteries, a cover, and a moisture resistant sealer.