Non-invasive localization and treatment of focal atrial fibrillation

• US 6,760,620 B2
• Filed: 03/14/2001
• Issued: 07/06/2004
• Est. Priority Date: 03/15/2000
• Status: Expired due to Fees

• Current Assignee: Resolution Medical, Inc.
• Original Assignee: Resolution Medical, Inc.
• Inventors: Sippens Groenewegen, Arne
• Primary Examiner(s): Jastrzab, Jeffrey R.
• Application Number:
  US09/808,728
• Publication Number:
  US 20010056289A1
• Time in Patent Office: 1,210 Days
• Field of Search: 600/508-510, 600/515-518, 607/5
• US Class Current: 607/5
• 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 external body surface, the method comprising;

measuring the fibrillation from the body surface by sensing heart cycle signals while no intracardiac probe is present in the heart;

locating an arrhythmogenic region of the heart in response to the measured fibrillation such that the arrhythmogenic region is determined using the sensed heart cycle signals prior to intracardiac access; and

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

2. The method of claim 1, 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.

3. The method of claim 1, 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 signal with the signal separator.

4. The method of claim 3, further comprising selecting at least one reference cycle from among a plurality of heart cycles, wherein the arrhythmogenic region is determined at least in part from the separated heart cycle signals during the at least one reference cycle.

5. The method of claim 4, further comprising selecting a time portion of the at learnt one reference cycle and comparing separated signals from an array of sensing location during the selected time portion.

6. The method of claim 5, further comprising generating a data matrix by integrating the separated atrial signals, the separated atrial signals comprising potential value signals from each sensor location, the separated atrial signal 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.

7. The method of claim 6, 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.

8. The method of claim 3, 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.

9. 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.

10. The method of claim 9, wherein the locating step is performed so that the located arrhythmogenic region barn a surface area of less than about 5 cm².

11. The method of claim 9, wherein the locating step is performed so that an outer radius of the arrhythmogenic region is less than about 2.5 cm.

12. The method of claim 9, wherein the locating step is performed so that an outer radius of the arrhythmogenic region is about 1.5 cm or less.

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

14. The method of claim 13, wherein the probe comprises a pacing probe, and further comprising initialing 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.

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

16. A method for treating arrhythmia in a heart of a patient, the patient having an accessible body surface, the heart having a left atrium, a left ventricle, a right atrium, and a right ventricle, heart signals at the body surface including atria signals superimposed with ventricular signals, the atrial and ventricular signals being separable by a signal separator, a database having information regarding a plurality of known cycles, each known cycle having an associated known arrhythmogenic region, the method comprising:

sensing signals during an arrhythmia-initiation cycle or an atrial premature beat cycle from the body surface;

separating the atrial signals from the sensed signals with the signal separator;

locating an arrhythmogenic region of an arrhythmogenic atrium of the heart prior to any introduction of a cardiac probe into the heart by comparing the separated signals to the database; and

directing a treatment at or near an ectopic site or an exit site within the arrhythmogenic region so that the arrhythmia is inhibited.

17. A system for treating arrhythmia in a heart of a patient, the patient having an exposed body surface and the heart having an atrium and a ventricle, wherein a sensor array is coupled to the body surface for sensing heart cycle signals, the heart signals including atrial signals superimposed with ventricular signals, the atrial and ventricular signals being separable by a signal separator, and wherein a database has information regarding a plurality of known cycles, each known cycle having an associated known arrhythmogenic region, the system comprising:

a processor coupled to the database, the processor deriving an arrhythmogenic region of the atrium from the heart cycle signals by separating the atrial or ventricular signals with the signal separator and comparing the separated signals to the database; and

a probe for directing treatment at or near an ectopic origin or exit site within the arrhythmogenic region so that the arrhythmia is inhibited.

18. The system of claim 17, the sensor array having an array of sensors and defining an array of sensor locations, wherein the processor stores at least one reference cycle from among a plurality of heart cycles and a selected time portion of the at least one reference cycle, and wherein the processor is configured to locate the arrhythmogenic region by comparing the separated signals from the array of sensing locations during the selected time portion by integrating a potential value of the separated atrial signals from each sensor location within the selected time portion so as to define an integral value, and arranging the integral values within a data matrix according to associated sensor locations along the body surface.

19. 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 by sensing heart cycle signals at an array of sensing locations while no intracardiac probe is present in the heart, the heart cycle signals including an atrial signal superimposed with a ventricular signal;

selecting at least one reference cycle from among a plurality of heart cycles;

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

selecting a time portion of the at least one reference cycle;

separating the atrial and ventricular signals with a signal separator, and

comparing the separated signals from the array of sensing locations during the selected time portion by integrating a potential value of the separated signals from each sensor location within the selected time portion so as to define an integral value, and arranging the integral value within a data matrix according to associated sensor locations along the body surface; and

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

20. The method of claim 19, further comprising sensing the heart cycle signals with an ray of signals while the sensor stray is coupled to thoracic skin of the patient, the array having more than 20 sensing locations.

21. The method of claim 19, 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.

22. The method of claim 19, 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.

23. The method of claim 19, 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.

24. The method of claim 23, wherein the locating step is performed so that the located arrhythmogenic region has a surface area of less than about 5 cm².

25. The method of claim 23, wherein the locating step is perform so that an outer radius of the arrhythmogenic region is less than about 2.5 cm.

26. The method of claim 23, wherein the locating step is performed so that an outer radius of the arrhythmogenic region is about 1.5 cm or less.

27. The method of claim 19, 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.

28. The method of claim 27, 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.

29. The method of claim 19, wherein the directing step comprises ablating at or near an ectopic site or exit site.