Monitor recorder-implemented method for electrocardiography value encoding and compression

• US 9,730,641 B2
• Filed: 08/08/2016
• Issued: 08/15/2017
• Est. Priority Date: 09/25/2013
• Status: Active Grant

• Current Assignee: Bardy Diagnostics, Inc. (Baxter International Inc.)
• Original Assignee: Bardy Diagnostics, Inc. (Baxter International Inc.)
• Inventors: Felix, Jason, Dreisbach, Ezra M.
• Primary Examiner(s): Schaetzle, Kennedy
• Application Number:
  US15/231,657
• Publication Number:
  US 20160345909A1
• Time in Patent Office: 372 Days
• CPC Class Codes: A61B 5/0006 ECG or EEG signals
• CPC Class Codes: A61B 5/1118 Determining activity level
• CPC Class Codes: A61B 5/259 using conductive adhesive means, e.g. gels
• CPC Class Codes: A61B 5/282 Holders for multiple electrodes for introduction into the body A61B5/287
• CPC Class Codes: A61B 5/316 Modalities, i.e. specific diagnostic methods
• CPC Class Codes: A61B 5/333 Recording apparatus specially adapted therefor
• CPC Class Codes: A61B 5/349 Detecting specific parameters of the electrocardiograph cycle
• CPC Class Codes: A61B 5/6823 Trunk, e.g., chest, back, abdomen, hip
• CPC Class Codes: A61B 5/6833 Adhesive patches
• CPC Class Codes: A61B 5/721 using a separate sensor to detect motion or using motion information derived from signals other than the physiological signal to be measured
• CPC Class Codes: A61B 5/7232 involving compression of the physiological signal, e.g. to extend the signal recording period

Abstract

A monitor recorder-implemented method for electrocardiography value encoding and compression is provided. A plurality of codes are maintained, each associated with an electrocardiography value range. A series of electrocardiography values is obtained. A serial accumulator is set to a predetermined value; each of the obtained electrocardiography values from the series of the obtained electrocardiography values is processed, including: performing a mathematical operation on that obtained electrocardiography value and the serial accumulator; identifying the code within the range associated with which a result of the mathematical operation falls; representing that obtained electrography value with the identified code; and adjusting the serial accumulator by a value derived from the range associated with the identified code. Each of the represented codes are into a sequence in a non-volatile memory.

Claims

1. A monitor recorder-implemented method for electrocardiography value encoding and compression, comprising the steps of:

maintaining a plurality of codes, each associated with an electrocardiography value range;

obtaining a series of electrocardiography values;

setting a serial accumulator to a predetermined value;

processing each of the obtained electrocardiography values from the series of the obtained electrocardiography values, comprising the steps of;

performing a mathematical operation on that obtained electrocardiography value and the serial accumulator;

identifying the code within the range associated with which a result of the mathematical operation falls;

representing that obtained electrography value with the identified code; and

adjusting the serial accumulator by a value derived from the range associated with the identified code; and

writing each of the represented codes into a sequence into a non-volatile memory,

wherein the steps are performed by a monitor recorder.

2. A method according to claim 1, further comprising:

setting a further range that is between 0 and 1 for an initial one of the codes in the sequence; and

processing each of the codes remaining in the sequence, comprising;

obtaining an estimation of probabilities of the codes appearing next to that code in the sequence;

dividing the further range into sub-ranges, each sub-range representing a fraction of the further range proportional to the probabilities of the next codes;

selecting the sub-range corresponding to the code next to that code in the sequence;

representing the next code by the selected sub-range in a non-volatile memory; and

adjusting the further range to equal the assigned sub-range for the processing of another one of the codes.

3. A method in accordance with claim 2, wherein the estimations of the probabilities are obtained using a statistical model.

4. A method in accordance with claim 2, further comprising:

maintaining a plurality of tables, each of the tables comprising numeric possibilities of a plurality of the codes appearing in the sequence successive to one of the codes; and

deriving the estimations of the probabilities from the tables.

5. A method in accordance with claim 2, wherein for one or more of the codes, the estimation of the probabilities of the codes successive to that code in the sequence appearing after that code in the sequence are obtained based on that code and the code preceding that code in the sequence.

6. A method in accordance with claim 1, wherein a size of one of the ranges is unequal to a size of another one of the ranges.

7. A method in accordance with claim 1, further comprising:

defining a size of each of the ranges based on a number of expected electrocardiography values within that range.

8. A method in accordance with claim 1, wherein a number of the ranges is a power of two.

9. A non-transitory computer readable storage medium storing code for executing on the monitor recorder to perform the method according to claim 1.

10. A monitor recorder-implemented method for electrocardiography value compression, comprising:

obtaining a sequence of codes, each of the codes representing an electrocardiography value within a range different than the ranges associated with the other ones of the codes;

setting a further range that is between 0 and 1 for an initial one of the codes in the sequence; and

processing each of the codes remaining in the sequence, comprising;

obtaining an estimation of probabilities of the codes appearing next to that code in the sequence;

dividing the further range into sub-ranges, each sub-range representing a fraction of the further range proportional to the probabilities of the next codes;

selecting the sub-range corresponding to the code next to that code in the sequence;

representing the next code by the selected sub-range in a non-volatile memory; and

adjusting the further range to equal the assigned sub-range for the processing of another one of the codes,

wherein the steps are performed by a monitor recorder.

11. A method in accordance with claim 10, wherein the probabilities are predicted using a statistical model.

12. A method in accordance with claim 10, further comprising:

maintaining a plurality of tables, each of the tables comprising the numeric possibilities of a plurality of the codes appearing in the sequence next to one of the codes; and

deriving the estimations of the probabilities from the tables.

13. A method in accordance with claim 10, wherein for one or more of the codes, the estimation of the probabilities of the codes next to that code in the sequence are obtained based on that code and the code preceding that code in the sequence.

14. A non-transitory computer readable storage medium storing code for executing on the monitor recorder to perform the method according to claim 10.

15. A electrocardiography monitor recorder, comprising:

a non-volatile memory;

a micro-controller operable to execute under a micro-programmable control and configured to;

obtain a plurality of codes, each associated with an electrocardiography value range;

set a serial accumulator to a predetermined value;

obtain a series of electrocardiography values;

process each of the obtained electrocardiography values from the series of the obtained electrocardiography values, comprising;

perform a mathematical operation on that obtained electrocardiography value and the serial accumulator;

identify the code within the range associated with which a result of the mathematical operation falls;

represent that obtained electrography value with the identified code; and

adjust the serial accumulator by a value derived from the range associated with the identified code; and

write each of the represented codes into a sequence in the non-volatile memory.

16. A monitor recorder in accordance with claim 15, wherein the micro-controller is further configured to:

set a further range that is between 0 and 1 for an initial one of the codes in the sequence; and

process each of the codes remaining in the sequence, comprising;

obtain an estimation of probabilities of the codes appearing next to that code in the sequence;

divide the further range into sub-ranges, each sub-range representing a fraction of the further range proportional to the probabilities of the next codes;

select the sub-range corresponding to the code next to that code in the sequence;

represent the next code by the selected sub-range in the non-volatile memory; and

adjust the further range to equal the assigned sub-range for the processing of another one of the codes.

17. A monitor recorder in accordance with claim 16, wherein for one or more of the codes, the estimation of the probabilities of the codes next to that code in the sequence are obtained based on that code and the code preceding that code in the sequence.

18. A monitor recorder in accordance with claim 15, wherein a size of one of the ranges is unequal to a size of another one of the ranges.

19. A monitor recorder in accordance with claim 15, wherein the micro-controller is further configured:

define a size of each of the ranges based on a number of expected electrocardiography values within that range.

20. A monitor recorder in accordance with claim 15, wherein a number of the ranges is a power of two.