Apparatus and method for reading and analyzing ECG images

• US 6,782,121 B2
• Filed: 04/22/2003
• Issued: 08/24/2004
• Est. Priority Date: 05/17/2001
• Status: Expired due to Term

• Current Assignee: AMPS, LLC
• Original Assignee: AMPS, LLC
• Inventors: Badilini, Fabio F.
• Primary Examiner(s): Johns, Andrew W.
• Assistant Examiner(s): NAKHJAVAN, SHERVIN K
• Application Number:
  US10/420,215
• Publication Number:
  US 20030194118A1
• Time in Patent Office: 490 Days
• Field of Search: 382/128, 382/130, 600/509, 600/513, 600/516, 600/518, 600/519, 600/522
• US Class Current: 382/128
• CPC Class Codes: A61B 5/349 Detecting specific parameters of the electrocardiograph cycle
• CPC Class Codes: A61B 5/36 Detecting PQ interval, PR interval or QT interval
• CPC Class Codes: G06T 7/60 Analysis of geometric attributes

Abstract

A method of analyzing electrocardiogram (ECG) data, including data derived from a paper chart, includes the steps of providing ECG data to create a computer-readable ECG data file representative of the ECG chart, storing the ECG data file in a memory of a computer, opening the ECG data file and displaying on a computer display an ECG plot corresponding to the ECG data file, calibrating the x-axis and y-axis of the displayed ECG plot with an x-axis scale and a y-axis scale, identifying characteristics of the ECG plot by using an input device connected to the computer, and measuring the identified characteristics.

Claims

1. A computerized method of analyzing electrocardiogram (ECG) data, comprising the steps of:

storing an ECG data file in a memory of a computer;

opening said ECG data file;

displaying an ECG plot of said ECG data file on a display of the computer;

calibrating an x-axis and a y-axis of said ECG plot by accessing a tool bar displayed on the computer display, selecting a button of said toolbar corresponding to one of the x-axis and the y-axis of said ECG plot to thereby select one of the x-axis and y-axis for calibration, and drawing a calibration line for one or both axes and assigning a calibrated scale to the length of the line and to the axes;

identifying characteristics of said ECG plot by using at least one input device connected to the computer;

drawing a feature line with a first end point at one feature and a second end point at a second feature; and

automatically finding the distance between the two end points as projected upon one or both axes of said ECG plot.

2. The method of claim 1, wherein said drawing step comprises:

drawing a calibration line of a predetermined length, said predetermined length corresponding to a default value; and

assigning said default value to a portion of the selected one of the x-axis and the y-axis, said portion having a portion length equal to said predetermined length.

3. The method of claim 2, comprising the further step of calculating a magnitude of a projection of said feature line onto one of the calibrated axes, said projection being substantially parallel to the selected axis, said magnitude corresponding to the product of the scale of the axis and the length of the projected line.

4. The method of claim 1, further comprising the step of inputting a value corresponding to a projection of said calibration line, said projection being substantially parallel to the selected one of the x-axis and the y-axis, said value being assigned to an equal length of the selected one of the x-axis and the y-axis.

5. A computerized method of analyzing electrocardiogram (ECG) data, comprising the steps of:

storing an ECG data file in a memory of a computer;

opening said ECG data file;

displaying an ECG plot of said ECG data file on a display of the computer;

calibrating an x-axis and a y-axis of said ECG plot by accessing a tool bar displayed on the computer display, selecting a button of said toolbar corresponding to one of the x-axis and the y-axis of said ECG plot to thereby select one of the x-axis and y-axis for calibration, and drawing a calibration line for one or both axes and assigning a calibrated scale to the length of the line and to the axes;

identifying characteristics of said ECG plot by using at least one input device connected to the computer, said identifying step comprising selecting with an input device at least one of an RR interval, a QT interval, a PR interval, a QRS interval, a baseline, a tangent line, and an onset of a QRS interval;

labeling the selected one of an RR interval, a QT interval and a QRS interval, a baseline and a tangent line;

drawing a feature line with a first end point at one feature and a second end point at a second feature; and

automatically measuring the distance between the two end points as projected upon one or both axes of said ECG plot.

6. The method of claim 5, wherein said identifying step further comprises selecting a first point on the ECG plot that corresponds to a beginning of a selected one of an RR interval, a QT interval, a PR interval, a QRS interval, a baseline, a tangent line, and an onset of a QRS interval, and selecting with an input device a second point on the ECG plot that corresponds to an end of the selected one of an RR interval, a QT interval, a PR interval a QRS interval, a baseline, a tangent line, and an onset of a QRS interval.

7. The method of claim 5, wherein said measuring step comprises calculating a duration of at least one of an RR interval, a QT interval, a PR interval and a QRS interval identified in said identifying step.

8. The method of claim 5, comprising the further step of calculating and displaying a baseline of said ECG plot.

9. The method of claim 8, wherein said calculating and displaying a baseline step is performed separately for each QRS interval of the ECG plot to thereby establish a respective baseline for each QRS interval.

10. The method of claim 5, comprising the further step of calculating with the tangent method a QT interval identified in said identifying step.

11. The method of claim 10, wherein said calculating with the tangent method step comprises:

accessing a tool bar displayed on the computer display;

selecting a button of said toolbar corresponding to said calculating with the tangent method step; and

displaying on the display the calculated QT interval.

12. The method of claim 5, comprising the further steps of:

calculating an average of the RR intervals identified in said identifying step and measured in said measuring step; and

calculating an average QT interval of the QT intervals identified in said identifying step and measured in said measuring step.

13. The method of claim 11, wherein each of said calculating an average of the RR intervals and said calculating an average QT interval comprises selecting a corresponding command form a dialog box displayed on the display.

14. The method of claim 5, comprising the further steps of:

exporting the results of said measuring step to a computer-readable file.

15. The method of claim 14, wherein said exporting step further comprises storing data representative of the ECG plot in said data file, storing data representative of said calibrating step, and storing data representative off said identifying step, to thereby enable subsequent display and analysis of the analyzed ECG plot.

16. The method of claim 5, wherein said labeling step comprises selecting with an input device a label from a menu displayed on the display of the computer, said label corresponding to the selected one of an RR interval, a QT interval, a PR interval, a QRS interval, a baseline, a tangent line, and an onset of a QRS interval.