ATRIAL FIBRILLATION DETECTION BASED ON ABSENCE OF CONSISTENT P-LOOPS IN AVERAGED VECTORCARDIOGRAM

• US 20110184300A1
• Filed: 01/26/2010
• Published: 07/28/2011
• Est. Priority Date: 01/26/2010
• Status: Abandoned Application

• Current Assignee: iCardiac Technologies, Inc. (Explorer Holdings, Inc.)
• Original Assignee: Newcardio, Inc.
• Inventors: Shvilkin, Alexei, Panescu, Dorin, Bojovic, Bosko, Hadzievski, Ljupco
• Application Number:
  US12/694,236
• Publication Number:
  US 20110184300A1
• Time in Patent Office: Days
• US Class Current: 600/512
• CPC Class Codes: A61B 5/341 Vectorcardiography [VCG]
• CPC Class Codes: A61B 5/361 Detecting fibrillation

Abstract

A method for determining the presence of atrial fibrillation includes obtaining data from at least three orthogonal leads indicative of electrical activity of a heart over multiple heart beats, averaging the data to obtain an average heart beat, generating, from the averaged data, an average heart beat vectorcardiogram (VCG) that is a function of voltage level, comparing, over a segment of the average heart beat, the average heart beat VCG with a threshold value, and indicating whether the average heart beat VCG exceeds or does not exceed the threshold value.

Claims

1. A method for determining the presence of atrial fibrillation, comprising:

obtaining data from at least three orthogonal leads indicative of electrical activity of a heart over multiple heart beats;

performing ensemble processing to generate a generalized heart beat;

generating a generalized vectorcardiogram (VCG) that is a function of voltage level;

comparing, over a segment of the generalized heart beat, the generalized VCG with a threshold value; and

indicating whether the generalized VCG exceeds or does not exceed the threshold value.

2. The method of claim 1, further comprising declaring atrial fibrillation if the threshold value is not exceeded.

3. The method of claim 1, further comprising declaring no atrial fibrillation if the threshold value is exceeded.

4. The method of claim 1, wherein obtaining data from at least three orthogonal leads comprises obtaining data from a standard 12-lead ECG (electrocardiogram).

5. The method of claim 1, wherein the segment spans from a first selected point upstream of a Q point of the generalized heart beat to a second selected point further upstream therefrom.

6. The method of claim 5, wherein the first selected point is about 5 to about 50 milliseconds downstream of the Q point.

7. The method of claim 5, wherein the first selected point is about 0.5 to about 10% of an R-R interval of the generalized heart beat.

8. The method of claim 5, wherein the second selected point is at the beginning of a cardiac cycle.

9. The method of claim 5, wherein the second selected point is at the end of a preceding T wave.

10. The method of claim 1, wherein generating a generalized heart beat comprises superimposing multiple heart beats using a common fiducial point.

12. The method of claim 1, wherein the generalized VCG is generated from the generalized heart beat.

13. The method of claim 1, wherein the generalized VCG is generated from a plurality of VCGs each corresponding to one of the multiple heart beats.

14. The method of claim 1, wherein the threshold is in the range of about 0.1 millivolts to about 0.3 millivolts.

15. The method of claim 1, wherein the threshold is about 0.15 millivolts.

16. The method of claim 1, further comprising selectively displaying the generalized VCG based on whether or not the threshold is exceeded.

17. The method of claim 1, wherein the ensemble processing comprises median filtering.

18. The method of claim 1, wherein the ensemble processing comprises generating a median beat.

11. The method of claim 11, wherein the common fiducial point is the R point in the cardiac cycle.

19. A system for determining the presence of atrial fibrillation, comprising:

a computer configured to receive data from at least three orthogonal leads indicative of electrical activity of a heart over multiple heart beats, the computer further configured to;

perform ensemble processing to generate a generalized heart beat;

generate a generalized vectorcardiogram (VCG) that is a function of voltage level;

compare, over a segment of the generalized heart beat, the generalized VCG with a threshold value; and

identify the generalized VCG as either exceeding or not exceeding the threshold value; and

an indicator configured to provide an indication of the identification.

20. The system of claim 19, wherein the computer is further configured to declare atrial fibrillation if the threshold value is not exceeded.

21. The system of claim 19, wherein the computer is further configured to declare no atrial fibrillation if the threshold value is exceeded.

22. The system of claim 19, wherein obtaining data from at least three orthogonal leads comprises obtaining data from a standard 12-lead ECG (electrocardiogram).

23. The system of claim 19, wherein the segment spans from a first selected point upstream of a Q point of the generalized heart beat to a second selected point further upstream therefrom.

24. The system of claim 23, wherein the first selected point is about 5 to about 50 milliseconds downstream of the Q point.

25. The system of claim 23, wherein the first selected point is about 0.5 to about 10% of an R-R interval.

26. The system of claim 23, wherein the second selected point is at the beginning of a cardiac cycle.

27. The system of claim 23, wherein the second selected point is at the end of a preceding T wave.

28. The system of claim 19, wherein generating a generalized heart beat comprises superimposing multiple heart beats using a common fiducial point.

29. The system of claim 28, wherein the common fiducial point is the R point in the cardiac cycle.

30. The system of claim 19, wherein the generalized VCG is generated from the generalized heart beat.

31. The system of claim 19, wherein the generalized VCG is generated from a plurality of VCGs each corresponding to one of the multiple heart beats.

32. The system of claim 19, wherein the threshold is in the range of about 0.1 millivolts to about 0.3 millivolts.

33. The system of claim 19, wherein the threshold is about 0.15 millivolts.

34. The system of claim 19, further comprising a display for selectively displaying the generalized VCG based on whether or not the threshold is exceeded.

35. The system of claim 19, wherein the ensemble processing comprises median filtering.

36. The system of claim 19, wherein the ensemble processing comprises generating a median beat.

37. A method for determining the presence of atrial fibrillation, comprising:

obtaining data from at least three orthogonal leads indicative of electrical activity of a heart over multiple heart beats;

averaging the data to obtain an average heart beat;

generating, from the averaged data, an average heart beat vectorcardiogram (VCG) that is a function of voltage level;

comparing, over a segment of the average heart beat, the average heart beat VCG with a threshold value; and

indicating whether the average heart beat VCG exceeds or does not exceed the threshold value.

38. A system for determining the presence of atrial fibrillation, comprising:

a computer configured to receive data from at least three orthogonal leads indicative of electrical activity of a heart over multiple heart beats, the computer further configured to;

average the data to obtain an average heart beat;

generate, from the averaged data, an average heart beat vectorcardiogram (VCG) that is a function of voltage level;

compare, over a segment of the average heart beat, the average heart beat VCG with a threshold value; and

identify the average heart beat VCG as either exceeding or not exceeding the threshold value; and

an indicator configured to provide an indication of the identification.

39. A program storage device readable by machine, embodying a program of instructions executable by the machine to perform a method, the method comprising:

obtaining data from at least three orthogonal leads indicative of electrical activity of a heart over multiple heart beats;

averaging the data to obtain an average heart beat;

generating, from the averaged data, an average heart beat vectorcardiogram (VCG) that is a function of voltage level;

comparing, over a segment of the average heart beat, the average heart beat VCG with a threshold value; and

indicating whether average heart beat VCG exceeds or does not exceed the threshold value.