DOUBLE BIPOLAR CONFIGURATION FOR ATRIAL FIBRILLATION ANNOTATION

• US 20150208942A1
• Filed: 12/30/2014
• Published: 07/30/2015
• Est. Priority Date: 01/29/2014
• Status: Active Grant

• Current Assignee: Biosense Webster Israel Ltd. (Johnson & Johnson)
• Original Assignee: Biosense Webster Israel Ltd. (Johnson & Johnson)
• Inventors: Bar-Tal, Meir, Houben, Richard P.M., Ben Zriham, Yaniv, Urman, Roy, Pressman, Assaf, Auerbach, Shmuel
• Granted Patent: US 9,554,718 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: A61B 18/1492 having a flexible, catheter-like structure, e.g. for heart ablation A61B18/1477 takes precedence
• CPC Class Codes: A61B 2018/0016 Energy applicators arranged in a two- or three dimensional array
• CPC Class Codes: A61B 2018/00267 having a basket shaped structure
• CPC Class Codes: A61B 2018/00839 Bioelectrical parameters, e.g. ECG, EEG
• CPC Class Codes: A61B 2034/2051 Electromagnetic tracking systems
• CPC Class Codes: A61B 34/20 Surgical navigation systems; Devices for tracking or guiding surgical instruments, e.g. for frameless stereotaxis
• CPC Class Codes: A61B 5/287 Holders for multiple electrodes, e.g. electrode catheters for electrophysiological study [EPS]
• CPC Class Codes: A61B 5/30 Input circuits therefor
• CPC Class Codes: A61B 5/316 Modalities, i.e. specific diagnostic methods
• CPC Class Codes: A61B 5/352 Detecting R peaks, e.g. for synchronising diagnostic apparatus; Estimating R-R interval
• CPC Class Codes: A61B 5/361 Detecting fibrillation
• CPC Class Codes: A61B 5/7203 for noise prevention, reduction or removal
• CPC Class Codes: A61B 5/7221 Determining signal validity, reliability or quality A61B5/7207 and A61B5/7217 take precedence
• CPC Class Codes: A61B 5/7235 Details of waveform analysis A61B5/349 takes precedence
• CPC Class Codes: A61B 5/726 using Wavelet transforms

Abstract

Catheterization of the heart is carried out by inserting a probe having electrodes into a heart of a living subject, recording a bipolar electrogram and a unipolar electrogram from one of the electrodes at a location in the heart, and defining a window of interest wherein a rate of change in a potential of the bipolar electrogram exceeds a predetermined value. An annotation is established in the unipolar electrogram, wherein the annotation denotes a maximum rate of change in a potential of the unipolar electrogram within the window of interest. A quality value is assigned to the annotation, and a 3-dimensional map is generated of a portion of the heart that includes the annotation and the quality value thereof.

Claims

1. A method, comprising the steps of:

inserting a probe into a heart of a living subject, the probe having electrodes;

recording a bipolar electrogram and a unipolar electrogram from one of the electrodes at a location in the heart;

defining a time interval comprising a window of interest wherein a rate of change in a potential of the bipolar electrogram exceeds a predetermined value;

establishing an annotation in the unipolar electrogram, wherein the annotation denotes a maximum rate of change in a potential of the unipolar electrogram within the window of interest;

assigning a quality value to the annotation; and

generating a 3-dimensional map of a portion of the heart wherein the map includes the annotation and the quality value thereof.

2. The method according to claim 1, wherein recording a bipolar electrogram comprises establishing a double bipolar electrode configuration of electrodes, the double bipolar electrode configuration comprising a first differential signal from a first pair of unipolar electrodes and a second differential signal from a second pair of unipolar electrodes, wherein the bipolar electrogram is measured as a time-varying difference between the first differential signal and the second differential signal.

3. The method according to claim 1, wherein establishing an annotation comprises computing a wavelet transform of the unipolar electrogram.

4. The method according to claim 3, further comprising producing a scalogram of the wavelet transform and determining the maximum rate of change in the scalogram.

5. The method according to claim 1, further comprising the steps of:

identifying from the quality value that the annotation is a qualified annotation that meets predetermined blocking criteria; and

indicating on the map that the qualified annotation is at or near a blocked region of the heart.

6. The method according to claim 1, wherein establishing an annotation comprises removing ventricular far field components from the unipolar electrogram.

7. The method according to claim 1, wherein establishing an annotation comprises determining if a temporal cycle length of the unipolar electrogram at the annotation lies within predefined statistical bounds for temporal cycle lengths of other annotations.

8. The method according to claim 1, further comprising the steps of:

adjusting the quality value of the annotation according to at least one of a quality value, inter-annotation distance and timing of another annotation.

9. The method according to claim 8, wherein the other annotation was generated from another unipolar electrogram that was read from another of the electrodes.

10. The method according to claim 1, further comprising the step of filtering the unipolar electrogram by an amount sufficient to reduce noise to a predetermined level, wherein assigning a quality value comprises determining the amount.

11. An apparatus, comprising:

an intra-body probe having a plurality of electrodes, the probe being configured to contact tissue in a heart;

a display; and

a processor, which is configured to receive an electrical signal from the electrodes and to perform the steps of;

recording a bipolar electrogram and a unipolar electrogram from one of the electrodes at a location in the heart;

defining a time interval comprising a window of interest wherein a rate of change in a potential of the bipolar electrogram exceeds a predetermined value;

establishing an annotation in the unipolar electrogram, wherein the annotation denotes a maximum rate of change in a potential of the unipolar electrogram within the window of interest;

assigning a quality value to the annotation; and

generating on the display a 3-dimensional map of a portion of the heart wherein the map includes the annotation and the quality value thereof.

12. The apparatus according to claim 11, wherein recording a bipolar electrogram comprises establishing a double bipolar electrode configuration of electrodes, the double bipolar electrode configuration comprising a first differential signal from a first pair of unipolar electrodes and a second differential signal from a second pair of unipolar electrodes, wherein the bipolar electrogram is measured as a time-varying difference between the first differential signal and the second differential signal.

13. The apparatus according to claim 11, wherein establishing an annotation comprises computing a wavelet transform of the unipolar electrogram.

14. The apparatus according to claim 13, further comprising producing a scalogram of the wavelet transform and determining the maximum rate of change in the scalogram.

15. The apparatus according to claim 11, further comprising the steps of:

identifying from the quality value that the annotation is a qualified annotation that meets predetermined blocking criteria; and

indicating on the map that the qualified annotation is at or near a blocked region of the heart.

16. The apparatus according to claim 11, wherein establishing an annotation comprises removing ventricular far field components from the unipolar electrogram.

17. The apparatus according to claim 11, wherein establishing an annotation comprises determining if a temporal cycle length of the unipolar electrogram at the annotation lies within predefined statistical bounds for temporal cycle lengths of other annotations.

18. The apparatus according to claim 11, wherein the probe has multiple rays, each of the rays having at least one electrode.

19. The apparatus according to claim 11, wherein the probe is a basket catheter having multiple ribs, each of the ribs having at least one electrode.