ELECTRODE DISPLACEMENT DETERMINATION
Methods and systems for determining whether a location of multiple current injecting electrodes has changed are disclosed herein.
1 .- 15 . (canceled)
16 . A system comprising:
one or more measuring electrodes positioned at one or more secure locations;
multiple current injecting electrodes at least some of the current injecting electrodes being placed in stable locations inside a patient's body to generate a field in an organ;
an electronic control system coupled to the multiple current injecting electrodes and to the one or more measuring electrodes and configured to:
cause current to flow among multiple current injecting electrodes;
in response to the current flow, measure a signal at the one or more measuring electrodes;
a processing system coupled to the electronic system and configured to:
generate a baseline signal measurement;
subsequent to generation of the baseline signal measurement, compare a measured signal from the one or more measuring electrodes to the baseline signal to generate a comparison result; and
determine whether a location of the multiple current injecting electrodes inside the patient's body has changed based on the comparison result.
17 . The system of claim 16 , further comprising an indicator configured to provide an audio or visual indication upon determining that the location of the multiple current injecting electrodes has changed.
18 . The system of claim 16 , wherein the one or more measuring electrodes comprise one or more ECG leads.
19 . The system of claim 16 , wherein the one or more measuring electrodes comprise one or more body surface electrodes.
20 . The system of claim 16 , wherein the system further comprises multiple measuring electrodes on a catheter and wherein:
the electronic control system is further configured to measure a signal at each of multiple measuring electrodes on the catheter for each of multiple locations of the catheter; and
the processing system is further configured to determine expected signals for the measuring electrodes at additional locations within the organ based on the measured signals.
21 . The system of claim 20 , wherein the processing system is further configured to determine a relative location of another catheter based on the signals measured by the multiple measuring electrodes on the catheter.
22 . The method of claim 16 , wherein the one or more measuring electrodes comprise one or more stable intracardiac electrodes.
23 . The system of claim 20 , wherein the processing system is further configured to compensate for respiration and heartbeat.
24 . The system of claim 20 , wherein the processing system is further configured to compare the measured field to the baseline signal using a residual norm between the baseline signal and the measured signal.
25 . The system of claim 24 , wherein the processing system is further configured to compare the measured field to the baseline signal by comparing the residual norm to a threshold value.
26 . The system of claim 16 , further comprising a display unit configured to provide information to enable a clinician to guide the current injecting electrodes to a location where the baseline signal measurement was generated.
27 . The system of claim 16 , further comprising a display unit configured to display a displacement trajectory.
28 . The method of claim 27 , wherein the displacement trajectory provides a three-dimensional model providing an indication of a current location of the current injecting electrodes and an indication of the location where the baseline signal measurement was generated.