Non-invasive localization and treatment of focal atrial fibrillation

• US 20050182336A1
• Filed: 05/19/2004
• Published: 08/18/2005
• Est. Priority Date: 03/15/2000
• Status: Abandoned Application

• Current Assignee: Resolution Medical, Inc.
• Original Assignee: Resolution Medical, Inc.
• Inventors: Sippens Groenewegen, Arne
• Application Number:
  US10/850,459
• Publication Number:
  US 20050182336A1
• Time in Patent Office: Days
• US Class Current: 600/518
• CPC Class Codes: A61B 5/061 Determining position of a probe within the body employing means separate from the probe, e.g. sensing internal probe position employing impedance electrodes on the surface of the body A61B1/00158 takes precedence
• CPC Class Codes: A61B 5/282 Holders for multiple electrodes for introduction into the body A61B5/287
• CPC Class Codes: A61B 5/322 Physical templates or devices for measuring ECG waveforms, e.g. electrocardiograph rulers or calipers by template matching A61B5/35
• CPC Class Codes: A61B 5/341 Vectorcardiography [VCG]
• CPC Class Codes: A61B 5/35 by template matching
• CPC Class Codes: A61B 5/363 Detecting tachycardia or bradycardia
• CPC Class Codes: A61B 5/364 Detecting abnormal ECG interval, e.g. extrasystoles, ectopic heartbeats
• CPC Class Codes: A61B 5/6831 Straps, bands or harnesses
• CPC Class Codes: A61B 5/6841 by using templates
• CPC Class Codes: A61B 5/743 Displaying an image simultaneously with additional graphical information, e.g. symbols, charts, function plots

Abstract

Devices, systems, and methods for localizing and/or treating arrhythmias of a patient'"'"'s heart, which are particularly useful for localizing focal atrial fibrillation, allow locating arrhythmogenic regions of a chamber of the heart using heart cycle signals measured from a body surface of the patient. Non-invasive localization of the ectopic origin or exit site allows focal, circular, and/or perimeter treatment to be directed so as to inhibit complex arrhythmias without having to rely on wide-spread and time consuming sequential searches and/or on massively invasive simultaneous electrocardial sensors. The invention recognizes that effective localization of these complex arrhythmias can be significantly enhanced by techniques and structures which separate heart cycle signals originating from differing chambers and/or regions of the heart tissue.

Claims

1. A method for treating fibrillation in a heart of a patient, the patient having an accessible body surface, the method comprising:

measuring the fibrillation from the body surface;

locating an arrhythmogenic region of the heart in response to the measured fibrillation; and

directing treatment at or near the arrhythmogenic region so that the fibrillation is inhibited.

2. The method of claim 1, further comprising sensing heart cycle signals while no intracardiac probe is present in the heart, the arrhythmogenic region being determined using the sensed heart cycle signals.

3. The method of claim 2, further comprising sensing the heart cycle signals with a two-dimensional array of sensors while the sensor array is coupled to thoracic skin of the patient, the array having more than 20 sensing locations.

4. The method of claim 2, the heart cycle signals including an atrial signal superimposed with a ventricular signal, the atrial and ventricular signals being separable by a signal separator, further comprising separating the atrial and ventricular signals with the signal separator.

5. The method of claim 4, further comprising selecting at least one reference cycle from among a plurality of heart cycles measured by the sensor array, wherein the arrhythmogenic region is determined at least in part from the separated heart cycle signals during the at least one reference cycle.

6. The method of claim 5, further comprising selecting a time portion of the at least one reference cycle and comparing separated signals from an array of sensing location during the selected time portion.

7. The method of claim 6, further comprising generating a data matrix by integrating the separated potential valve signals from each sensor location within the selected time portion so as to define an integral value, and arranging the integral values within the matrix according to locations of the associated sensor locations along the body surface.

8. The method of claim 7, further comprising graphically plotting the data matrix, determining lines of constant integral values along the plots, and identifying the arrhythmogenic region within an atrium of the heart using the lines of constant integral values.

9. The method of claim 4, a database having a plurality of known cycles, each known cycle having an associated known arrhythmogenic region, and further comprising comparing the signals during the at least one reference cycle to the known cycles of the database.

10. The method of claim 1, wherein the locating step comprises identifying an atrium having the arrhythmogenic region from among a left atrium and a right atrium of the heart of the patient with the measured fibrillation.

11. The method of claim 10, wherein the locating step is performed so that the located arrhythmogenic region has a surface area of less than about 5 cm2.

12. The method of claim 10, wherein the locating step is performed so that an outer radius of the arrhythmogenic region is less than about 2.5 cm.

13. The method of claim 10, wherein the locating step is performed so that an outer radius of the arrhythmogenic region is about 1.5 cm or less.

14. The method of claim 1, further comprising introducing a probe into an atrium after locating the arrhythmogenic region within the atrium and identifying an ectopic site or exit site with the probe.

15. The method of claim 14, wherein the probe comprises a pacing probe, and further comprising initiating an artificial arrhythmia by stimulating a candidate ectopic site within the arrhythmogenic region using the probe and comparing heart cycle signals from the artificial arrhythmia with the sensed signals.

16. The method of claim 1, wherein the directing step comprises ablating at or near an ectopic site or exit site.

21. The system of claim 4, wherein the processor analyzes a selected time portion of the at least one reference cycle and compares separated signals from an array of sensing location during the selected time portion.

22. The method of claim 21, wherein the processor generates a data matrix by integrating the separated atrial signals, the separated atrial signals comprising potential value signals from each sensor location, the separated atrial signals for each associated sensor location integrated within the selected time portion so as to define an integral value, and arranging the integral values within the matrix according to locations of the associated sensor locations along the body surface.

23. The system of claim 22, wherein the processor graphically displays plots of the data matrix, determines lines of constant integral values along the plots, and identifies the arrhythmogenic region within an atrium of the heart using the lines of constant integral values.

17. A system for localizing fibrillation in a heart of a patient, the patient having an external body surface, the system comprising:

an at least two-dimensional array of sensors for measuring the fibrillation from the body surface by sensing heart cycle signals while no intracardiac probe is present in the heart;

a processor configured to locate an arrhythmogenic region of the heart in response to the measured fibrillation such that the arrhythmogenic region can be determined using the sensed heart cycle signals prior to intracardiac access.

18. The system of claim 17, wherein the array of sensors comprises a plurality of thoracic skin sensors for coupling to the external body surface of the patient at more than 20 sensing locations.

19. The system of claim 17, the heart cycle signals including an atrial signal superimposed with a ventricular signal, the processor having a signal separator for separating the atrial and ventricular signals.

20. The system of claim 19, wherein the heart cycle signals correspond to at least one selecting reference cycle from among a plurality of heart cycles, wherein the processor determines the arrhythmogenic region at least in part from the separated heart cycle signals during the at least one reference cycle.

24. The system of claim 19, a database having a plurality of known cycles, each known cycle having an associated known arrhythmogenic region, wherein the processor compares the signals during the at least one reference cycle to the known cycles of the database.

25. The system of claim 17, wherein the processor locates the arrhythmogenic region by identifying an atrium having the arrhythmogenic region from among a left atrium and a right atrium of the heart of the patient with the measured fibrillation.

26. The system of claim 25, wherein the processor locates the arrhythmogenic region so that the located arrhythmogenic region has a surface area of less than about 5 cm2.

27. The system of claim 25, wherein the processor locates the arrhythmogenic region so that the located arrhythmogenic region is less than about 2.5 cm2.

28. The system of claim 25, wherein the processor locates the arrhythmogenic region so that the located arrhythmogenic region is about 1.5 cm or less 2.

29. The system of claim 17, further comprising a pacing probe introducible into an atrium after locating the arrhythmogenic region within the atrium, the probe capable of being used for identifying an ectopic site or exit site with the probe by stimulating a candidate ectopic site within the arrhythmogenic region such that the processor can compare heart cycle signals from a resulting artificial arrhythmia with the sensed signals.