LOCALIZATION SYSTEM AND METHOD USEFUL IN THE ACQUISITION AND ANALYSIS OF CARDIAC INFORMATION
Provided are a localization system and method useful in the acquisition and analysis of cardiac information. The localization system and method can be used with systems that perform cardiac mapping, diagnosis and treatment of cardiac abnormalities, as examples, and in the retrieval, processing, and interpretation of such types of information. The localization system and method use high impedance inputs, improved isolation, and relatively high drive currents for pairs of electrodes used to establish a multi-axis coordinate system. The axes can be rotated and scaled to improve localization.
1 . (canceled)
2 . A localization system, comprising:
at least one catheter configured for delivery of an electrode array comprising one or more biopotential electrodes to a body cavity defined by surrounding tissue;
a patient interface module comprising a plurality of localization electrodes configured for fixed orientation relative to the body, including pairs of localization electrodes that define axes of a coordinate system; and
a cardiac information console configured to:
drive the localization electrodes with localization signals having both a magnitude and a phase to establish an electrical field between localization electrodes in each pair of localization electrodes,
process current output at pairs of the localization electrodes to establish a manipulatable coordinate system for the tissue, wherein the coordinate system is manipulatable to rotate, make shorter, and/or make longer the axes, to modify a representation of the electrode array, and
process biopotential signals sensed and/or recorded by the biopotential electrodes to orient the biopotential electrodes within the coordinate system.
3 . The localization system of claim 2 , wherein the cavity is a heart chamber and the surrounding tissue is one or more walls of the heart chamber.
4 . The localization system of claim 2 , wherein the electrode array is a 3D array.
5 . The localization system of claim 4 , wherein the 3D array includes a plurality of splines.
6 . The localization system of claim 4 , wherein the 3D array is a basket array, a spiral array, a balloon, radially deployable arms, and/or other expandable and compactible structures.
7 . The localization system of claim 4 , wherein the cardiac information console is configured to generate an electronic representation of the 3D array-of the biopotential electrodes in a non-orthogonal coordinate system.
8 . The localization system of claim 7 , wherein the cardiac information console is further configured to graphically adjust and correct the electronic representation of the 3D array of biopotential electrodes in the non-orthogonal coordinate system by
applying an axis correction factor to voltage data determined from the biopotential signals, based on a known and/or measured shape of the 3D array;
determining a scaling matrix and applying the scaling matrix to a sensed voltage data, based on a known and/or measured shape of the electrode array;
calculating position values of each electrode, each electrode having a corrected voltage value based on the axis correction and scaling of the voltage data; and
fitting the calculated position values of each electrode to a known basket configuration.
9 . The localization system of claim 7 , wherein the cardiac information console is further configured to fit the electronic representation of the 3D array of biopotential electrodes in the non-orthogonal coordinate system to a known or determined geometry of the 3D array.
10 . The localization system of claim 8 , further comprising:
a user interface system configured to display the electronic representation of the 3D array and the coordinate system.
11 . The localization system of claim 10 , wherein the user interface system includes a mechanism that enables a user to rotate and/or scale the coordinate system to graphically adjust and correct an image of the electronic representation of the 3D array.
12 . The localization system of claim 2 , wherein the patient interface module includes a patient isolation drive system, and the plurality of localization electrodes include a set of patch electrodes and one or more reference electrodes.
13 . The localization system of claim 12 , wherein the plurality of localization electrodes include one or more pairs of localization electrodes.
14 . The localization system of claim 13 , wherein each pair of localization electrodes defines an axis of a non-orthogonal coordinate system.
15 . The localization system of claim 14 , wherein the isolation drive system is configured to maintain simultaneous output on all axes generated by the localization electrode pairs.
16 . The localization system of claim 13 , wherein the plurality of localization electrodes include three pairs of localization electrodes defining axes, each pair of localization electrodes defining one axis of a non-orthogonal coordinate system.
17 . The localization system of claim 16 , wherein:
a first pair of localization electrodes has two patch electrodes placed on opposite sides of ribs;
a second pair of localization electrodes has one patch electrode placed on the lower back and one patch electrode placed on an upper chest; and
a third pair of localization electrodes has one patch electrode placed on an upper back and one patch electrode placed on the lower abdomen.
18 . The localization system of claim 16 , wherein the axes of the non-orthogonal coordinate system are non-orthogonal to a natural axis of the body.
19 . The localization system of claim 13 , wherein each pair of localization electrodes is driven by a different localization signal.
20 . The localization system of claim 19 , wherein each localization signal has a different frequency.
21 . The localization system of claim 2 , wherein the cardiac information console further comprises, for each of the biopotential electrodes:
a biopotential signal path having a high impedance input and configured to receive the biopotential signals from the biopotential electrodes; and/or
a localization signal path having a high impedance input and configured to receive the localization signals from the biopotential electrodes.
22 . The localization system of claim 21 , wherein the cardiac information console further comprises, for each of the biopotential electrodes:
a DFIB protection circuit coupled between the biopotential signal path and the localization signal path.
23 . The localization system of claim 21 , wherein the cardiac information console further comprises:
an ADC, for each of the biopotential electrodes, coupled to outputs of the biopotential signal path and the localization signal path;
an IQ demodulator, for each of the biopotential electrodes, coupled to an output of the ADC;
a narrow band IIR filter coupled to the IQ demodulator; and
a time filter coupled to the IIR filter, and configured to selectively filter out portions of data on a time basis.
24 . The localization system of claim 23 , wherein there is an independent IIR filter for each of I and Q components for each IQ demodulator.
25 . The localization system of claim 23 , wherein there is one multichannel IIR filter for a plurality of IQ demodulators.
26 . The localization system of claim 2 , wherein the at least one catheter further includes ultrasound electrodes configured to collect image data to generate one or more images of the tissue.
27 . The localization system of claim 26 , wherein the cardiac information console further comprises:
an ultrasound signal path having a high impedance input and configured to receive ultrasound signals from the ultrasound electrodes.