Catheter shape detection for mapping and ablation catheters

Abstract

A system for facilitating ablation in a patient's heart is disclosed. The system includes a catheter and a controller. The catheter includes an electrode assembly having a plurality of spaced apart electrodes disposed on a plurality of splines to generate an electric field in the heart, the splines being configurable in a deployed position wherein the plurality of spaced apart electrodes are in a selected spatial relationship, and wherein the splines are deformable relative to the deployed position when subjected to a force. A controller configured to measure an electrical signal received from an electrode of the plurality of spaced apart electrodes in response to the electric field, the electrical signal being indicative of a parameter of the electric field; and the controller is configured to determine a deformation of the spline relative to the deployed position based on the measured electrical signal.

Description

Technical Field

[0001] The present disclosure relates to medical systems and methods for promoting ablation of tissue in a patient. More particularly, the present disclosure relates to medical systems and methods for promoting ablation of tissue by electroporation. Background Art

[0002] Ablation procedures are used to treat a variety of different conditions in patients. Ablation can be used to treat arrhythmias, benign tumors, malignant tumors, and to control bleeding during surgery. Generally, ablation is achieved by thermal ablation techniques, including radio-frequency (RF) ablation and cryoablation. In RF ablation, a probe is inserted into the patient, and radio-frequency waves are delivered through the probe to the surrounding tissue. The radio-frequency waves generate heat, which destroys the surrounding tissue and cauterizes blood vessels. In cryoablation, a hollow needle or cryoprobe is inserted into the patient, and a cooling and thermally conductive fluid is circulated through the probe to freeze and kill the surrounding tissue. RF ablation and cryoablation techniques can kill tissue indiscriminately by cell necrosis, which can damage or kill otherwise healthy tissue, such as tissue in the esophagus, phrenic nerve cells, and tissue in the coronary arteries.

[0003] Another ablation technique uses electroporation. In electroporation (or electropermeabilization), an electric field is applied to cells in order to increase the permeability of the cell membrane. Depending on the strength and duration of the electric field, electroporation can be reversible or irreversible. If electroporation is reversible, the temporarily increased permeability of the cell membrane can be used to introduce chemicals, drugs, or deoxyribonucleic acid (DNA) into the cells before the cells heal and recover. Tissue recovery can occur within minutes, hours, or days after ablation is completed. If electroporation is irreversible, the affected cells are killed, such as via forms of cell death, which may be such as programmed cell death (e.g., by apoptosis) or such as traumatic cell death (e.g., by necrosis).

[0004] Irreversible electroporation can be used as a non-thermal ablation technique. In irreversible electroporation, a sequence of short high-voltage pulses is used to generate an electric field strong enough to kill cells. In ablation of cardiac tissue, irreversible electroporation can be a relatively safe and effective alternative to thermal ablation techniques that kill indiscriminately, such as RF ablation and cryoablation. Irreversible electroporation can be used to kill target tissue by using an electric field strength and duration selected to be sufficient to kill the target tissue (such as myocardial tissue) but not sufficient to permanently damage other cells or tissues (such as non-target myocardial tissue, red blood cells, vascular smooth muscle tissue, endothelial tissue, and nerve cells). Summary of the Invention

[0005] In Example 1, a system for facilitating ablation in a patient's heart, the system comprising a catheter and a controller. The catheter includes an electrode assembly having a plurality of spaced-apart electrodes disposed on a plurality of splines to generate an electric field in the heart, the splines being configurable to a deployed position in which the plurality of spaced-apart electrodes are in a selected spatial relationship, and wherein the splines are deformable relative to the deployed configuration when subjected to a force. The controller is configured to measure an electrical signal received from an electrode among the plurality of spaced-apart electrodes in response to the electric field, the electrical signal indicative of a parameter of the electric field; and the controller is configured to determine a deformation of the splines relative to the deployed position based on the measured electrical signal.

[0006] In Example 2, the system according to Example 1, wherein the deformation of the splines is determined based on a determination of the positions of the plurality of electrodes from the measured electrical signal.

[0007] In Example 3, the system according to any one of Examples 1 to 2, wherein the deformation of the splines is determined based on the distance between the plurality of spaced-apart electrodes from the measured electrical signal.

[0008] In Example 4, the system according to any one of Examples 1 to 3, wherein the controller is configured to measure a plurality of electrical signals received from the plurality of spaced-apart electrodes in response to the electric field, the plurality of electrical signals indicative of parameters of the electric field.

[0009] In Example 5, the system according to any one of Examples 1 to 3, wherein the determination of the deformation includes a determination of the amount of deformation of the splines relative to the deployed position.

[0010] In Example 6, the system according to Example 5, wherein the controller is configured to generate a visualization of a gradient based on the amount of deformation of the splines relative to the deployed position.

[0011] In Example 7, the system according to any one of Examples 5 to 6, wherein the controller is configured to generate a visualization of the deformation of the splines.

[0012] In Example 8, the system according to Example 7, the controller is configured to highlight a deformed spline among the plurality of splines in the visualization of the deformation of the splines.

[0013] In Example 9, the system according to any one of Examples 7 to 8, wherein the controller is configured to generate a visualization of the deformation of the splines on an electroanatomical map of the heart.

[0014] In Example 10, the system according to any one of Examples 1 to 9, wherein the controller is configured to determine the deformation of the splines relative to the deployed position substantially in real time.

[0015] In Example 11, the system according to any one of Examples 1 to 10, wherein determining the deformation includes determining the distension of the tissue.

[0016] In Example 12, the system according to any one of Examples 1 to 11, wherein the catheter includes a shaft having a distal region, and the plurality of splines form a basket structure in the deployed position, wherein each of the plurality of splines includes a proximal end and a distal end, the basket structure is coupled to the distal region, and the distal ends of the splines form the distal tip region of the basket structure.

[0017] In Example 13, the system according to Example 12, wherein the plurality of electrodes includes measurement electrodes disposed within the basket structure and configured not to contact the tissue when the catheter is in the deployed position.

[0018] In Example 14, the system according to Example 13, wherein the plurality of electrodes includes distal indifferent electrodes disposed within the basket structure and coupled to the distal tip region.

[0019] In Example 15, the system according to any one of Examples 12 to 14, wherein the plurality of electrodes includes shaft electrodes disposed on the distal region of the shaft and proximal to the basket structure.

[0020] In Example 16, a system for facilitating ablation, the system including a catheter and a controller. The catheter includes an electrode assembly having a plurality of spaced-apart electrodes disposed on a plurality of splines to generate an electric field, the splines being configurable to a deployed position, wherein the plurality of spaced-apart electrodes are in a selected spatial relationship, and wherein the splines are deformable relative to the deployed position when subjected to a force. The controller is configured to measure an electrical signal received from an electrode of the plurality of spaced-apart electrodes in response to the electric field, the electrical signal indicative of a parameter of the electric field; the controller is configured to determine a deformation of the splines relative to the deployed position based on the measured electrical signal.

[0021] In Example 17, the system according to Example 17, wherein the catheter includes a shaft having a distal region, and the plurality of splines form a basket structure in the deployed position, wherein each of the plurality of splines includes a proximal end and a distal end, the basket structure is coupled to the distal region, and the distal ends of the splines form the distal tip region of the basket structure.

[0022] In Example 18, the system according to Example 17, wherein the plurality of electrodes includes measurement electrodes disposed within the basket structure and configured not to contact the tissue when the catheter is in the deployed position.

[0023] In Example 19, the system according to Example 18, wherein the measurement electrode provides an electrical signal.

[0024] In Example 20, the system according to Example 18, wherein the plurality of electrodes includes distal indifferent electrodes disposed within a basket structure and coupled to a distal tip region, and the controller is configured to determine a distance between the measurement electrode and the distal indifferent electrodes.

[0025] In Example 21, the system according to Example 16, wherein the deformation of the spline is determined based on the determination of the position of each of the plurality of electrodes from the measured electrical signal.

[0026] In Example 22, the system according to Example 16, wherein the determination of the deformation includes the determination of the amount of deformation of the spline relative to the deployed position.

[0027] In Example 23, the system according to Example 22, wherein the controller is configured to determine an amount of force applied to the spline based on the determination of the amount of deformation.

[0028] In Example 24, the system according to Example 16, wherein the controller is configured to generate a visualization based on the deformation.

[0029] In Example 25, the system according to Example 24, wherein the controller is configured to generate a visualization of the gradient based on the amount of deformation of the spline relative to the deployed position.

[0030] In Example 26, the system according to Example 24, wherein the controller is configured to highlight the deformed splines among the plurality of splines.

[0031] In Example 27, the system according to Example 24, wherein the controller is configured to generate a visualization of the deformation on an electroanatomical map of the heart.

[0032] In Example 28, an electroporation catheter for an organ, the electroporation catheter includes an elongate shaft having a distal region; and an electrode assembly operatively coupled to the distal region. The electrode assembly has a plurality of spaced-apart electrodes disposed on a plurality of splines to generate an electric field, the splines being configurable to an expanded position in which the plurality of spaced-apart electrodes are in a selected spatial relationship, and wherein the splines are deformable relative to the expanded position when subjected to a force. The plurality of splines form a basket structure that defines a cavity in the expanded position, wherein each of the plurality of splines includes a proximal end and a distal end, the basket structure is coupled to the distal region, wherein the distal ends of the splines form a distal tip region of the basket structure, and the shaft has a distal basket structure region that extends into the cavity and terminates within the cavity. The plurality of electrodes includes a measurement electrode disposed on the distal basket structure region of the shaft and within the basket structure, the measurement electrode being configured not to contact tissue when the splines are in the expanded position.

[0033] In Example 29, the catheter according to Example 28, wherein the plurality of electrodes includes a distal reference electrode disposed within the basket structure and coupled to the distal tip region, the distal reference electrode being spaced apart from the shaft and the measurement electrode.

[0034] In Example 30, the catheter according to Example 29, wherein the plurality of electrodes includes shaft electrodes disposed on the distal region of the shaft and proximal to the basket structure.

[0035] In Example 31, a process for facilitating ablation in a patient's heart, the process includes: generating an electric field in the heart using a catheter, the catheter including an electrode assembly having a plurality of spaced-apart electrodes disposed on a plurality of splines to generate an electric field, the splines being configurable to an expanded position in which the plurality of spaced-apart electrodes are in a selected spatial relationship, and wherein the splines are deformable relative to the expanded position when subjected to a force. The process includes: measuring an electrical signal received from an electrode among the plurality of spaced-apart electrodes in response to the electric field, the electrical signal indicating a parameter of the electric field. The process includes: determining a deformation of the splines relative to the expanded position based on the measured electrical signal, wherein the deformation of the splines is determined based on determining a position of each of the plurality of electrodes relative to the electrode assembly from the measured electrical signal.

[0036] In Example 32, the process according to Example 31, further includes: determining an amount of force applied to the catheter based on the determination of the amount of deformation.

[0037] In Example 33, the process according to Example 31, further includes: generating a visualization based on the deformation on a graphical display.

[0038] In Example 34, the process according to Example 33, wherein generating the visualization includes: generating a visualization of the deformation of the splines on an electroanatomical map of the heart.

[0039] In Example 35, according to the process described in Example 31, wherein determining the deformation further includes: determining the amount of tissue dilation based on the amount of contact of the plurality of electrodes determined to be in contact with the heart, the position of the catheter determined to be within the heart, and the amount of deformation determined.

[0040] Although multiple embodiments are disclosed, other embodiments of the present invention will be apparent to those skilled in the art from the following detailed description, which shows and describes illustrative embodiments of the present invention. Accordingly, the drawings and detailed description are to be regarded as illustrative in nature and not restrictive. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] Figure 1 is a schematic diagram showing an exemplary clinical environment for treating a patient and treating the patient's heart using an electrophysiological system according to embodiments of the subject matter of the present disclosure.

[0042] Figure 2 is a schematic diagram showing a part of an exemplary catheter of an exemplary electrophysiological system that can be used for Figure 1 of.

[0043] Figure 3A is a schematic diagram showing a part of an exemplary catheter in Figure 1 the chamber of the patient's heart of Figure 2 of, the catheter being in a deployed position.

[0044] Figure 3B is a schematic diagram showing Figure 3A a part of an exemplary catheter that is in a first deformed state from the deployed position.

[0045] Figure 3C is a schematic diagram showing Figure 3A a part of an exemplary catheter that is in a second deformed state from the deployed position, wherein the second deformed state includes a greater amount of deformation than the first deformed state relative to the deployed position.

[0046] Figure 4 is a block diagram showing an exemplary controller of an exemplary electrophysiological system for Figure 1 of.

[0047] Figure 5 is a flowchart showing an exemplary configuration of an exemplary controller for Figure 4 of.

[0048] While the present invention is susceptible to various modifications and alternative forms, specific embodiments have been shown by way of example in the drawings and are described in detail below. However, the intention is not to limit the present invention to the specific embodiments described. On the contrary, the present invention is intended to cover all modifications, equivalents, and alternatives falling within the scope of the present invention as defined by the appended claims. Detailed Description

[0049] For purposes of promoting an understanding of the principles of the present disclosure, reference is now made to the examples illustrated in the drawings, which are described below. The illustrative examples disclosed herein are not intended to be exhaustive or to limit the present disclosure to the precise forms disclosed in the following detailed description. On the contrary, the exemplary embodiments are selected and described so that others skilled in the art may utilize their teachings. The use of multiple (e.g., all) features from one example in all examples does not exceed the scope of the present disclosure. Thus, no single figure should be construed as having any dependency or requirement related to any single component or combination of components shown therein. Additionally, the various components depicted in the drawings may be integrated with various components (or components not shown) among those depicted in other examples, all of which are considered to be within the scope of the present disclosure.

[0050] When applied to an electrophysiological system, irreversible electroporation uses high-voltage, short-duration pulses to kill cells such as myocardial cells by apoptosis while avoiding damage to other adjacent tissues including esophageal vascular smooth muscle and endothelium. Irreversible electroporation therapy can be delivered in multiple treatment segments. The treatment segments (which can have a duration on the order of milliseconds) can include multiple electrical pulses generated and delivered by an electroporation device, such as several dozen pulses, which is powered by an electroporation generator. In one example, the electroporation device is disposed near the tip of a catheter and is not visible to the naked eye when deployed. Due to issues associated with data related to acute visualization or indication of whether an electroporation mapping or ablation mechanism, such as an electrode assembly on the distal region of a catheter, is in contact with tissue, it can be difficult to determine the location for irreversible electroporation ablation during a procedure.

[0051] To determine the electrode position or electrode assembly position of an electroporation ablation catheter in a conductive medium such as the intracardiac space of a patient's heart-like chamber, many clinicians prefer to use an electroanatomical mapping system rather than fluoroscopy, which can reduce the patient's exposure time to radiation. An electroanatomical mapping system can be used to create a real-time three-dimensional view of the heart and intracardiac electrical activity. Some examples of electroanatomical mapping systems employ a multi-electrode basket catheter to rapidly record electrical activity at multiple locations within the heart, which can make the electroanatomical map more accurate. Such a catheter can include a self-expanding spline having multiple electrodes. The spline is arranged in a three-dimensional shape similar to an inflated balloon to allow the catheter to conform to the shape and motion of the heart chamber.

[0052] Information about how or whether a catheter contacts tissue can assist mapping and ablation procedures in an electrophysiology system. Additionally, information about the dilation of tissue contacted by the catheter can assist in creating lesions and determining the interaction of the catheter with anatomical structures. Such information can be applied to determine the integrity of an electroanatomical map and can provide confidence in the accuracy of signals displayed at certain anatomical locations. With such information, a clinician can also avoid certain structures of the heart or esophagus. Further, information about whether the catheter contacts tissue can inform whether an ablation location is likely to result in an effective lesion.

[0053] Providing an indication of whether a catheter contacts tissue or the amount of contact with tissue and which features of the catheter are in contact can provide more effective mapping and ablation in an electrophysiology procedure. Methods for determining forces in a catheter have encountered difficulties. For example, a force sensor on the distal end of the catheter may use valuable space that could otherwise be used in other microdevices. Additionally, certain changes in the shape of a basket catheter due to contact with tissue cannot be effectively detected using a force sensor. Attempts to use tissue proximity indicators to determine contact also encounter difficulties with dielectric differences in different types of tissue. The present disclosure provides mechanisms and systems that can be applied to determine catheter-tissue contact or force and to determine catheter shape changes.

[0054] Figure 1 An example clinical environment 10 for treating a patient 20 (such as treating the heart 30 of patient 20) using an electrophysiology system 50 in accordance with the present disclosure is shown. The electrophysiology system 50 includes an electroporation catheter system 60 and an electroanatomical mapping (EAM) system 70. The example electroporation catheter system 60 includes an electroporation catheter 105, a guide sheath 110, and an electroporation console 130. Additionally, the electroporation catheter system 60 includes various connection elements, such as cables, that operatively connect the components of the electroporation catheter system 60 to each other and to the components of the EAM system 70. Generally, the EAM mapping system 70 includes a positioning field generator 80, a mapping and navigation controller 90, and a display 92. Additionally, the clinical environment 10 may also include additional devices (such as an imaging device 94 (represented by a C-arm)) and various controller elements (such as a foot controller 96) configured to allow an operator to control various aspects of the electrophysiology system 50. The clinical environment 10 can have Figure 1 other components and arrangements of components not shown.

[0055] The electroporation catheter system 60 is configured to deliver ablation electric field energy to target tissue in a patient's heart 30 to cause cell death in the tissue, such as rendering the tissue unable to conduct electrical signals. Additionally, the electroporation catheter system 60 is configured to generate an electric field using the electroporation catheter 105 to create and present on a display 92 an electroanatomical map of the patient's heart to assist a clinician in planning ablation by irreversible electroporation using the electroporation catheter 105 prior to delivering the ablation electric field energy. In an embodiment, the electroporation catheter system 60 is configured to generate an electric field based on the characteristics of the electroporation catheter 105 and the position of the electroporation catheter 105 within the patient 20 (such as the position within the patient 20's heart 30). The electroporation catheter system 60 is configured to generate a graphical representation of the electroporation catheter and the electroanatomical map based on the characteristics of the electroporation catheter 105 and the position of the electroporation catheter 105 within the patient 20 (such as the position within the patient 20's heart 30) and the characteristics of the tissue surrounding the catheter 105 (such as the measured tissue impedance). In one example, the electroporation catheter 105 is a mapping and ablation catheter that can be deployed collaboratively with the EAM system 70 during a mapping procedure, and deliver ablation electric field energy and ablate tissue via irreversible electroporation.

[0056] The introducer sheath 110 is operable to provide a delivery conduit through which the electroporation catheter 105 can be deployed to a specific target site within the patient's heart 30. Access to the patient's heart can be obtained through a blood vessel (such as a peripheral artery or vein). Once access to the blood vessel is obtained, the electroporation catheter 105 can be navigated within the patient's heart, such as within a chamber of the heart.

[0057] An exemplary electroporation catheter 105 includes an elongate catheter shaft and a distal region configured to be deployed near the target tissue, such as within a chamber of the patient's heart. The shaft can extend from an access point within the patient's body to the target tissue and generally defines a longitudinal axis of the electroporation catheter 105. The distal region can include a basket structure, balloon, spline, shaped tip, or other electrode deployment mechanism coupled to the shaft. The electrode deployment mechanism includes an electrode assembly or array that includes electrodes. For example, the electrode assembly can include a plurality of spaced-apart electrodes, or a plurality of spaced-apart collections or groups of spaced-apart electrodes. In some examples, electrodes (such as a plurality of spaced-apart electrodes) can be deployed on the catheter shaft to supplement or replace the electrodes on the electrode deployment mechanism. For example, the electrode deployment mechanism includes a plurality of splines configured to form a basket structure, and at least some of the electrodes are disposed on the splines.

[0058] The electroporation catheter 105 can be configured in multiple positions. For example, when the distal region of the catheter 105 is within the introducer sheath 110, such as when traveling to a patient's heart chamber, the electrode deployment mechanism and the electrode assembly are in a retracted position to fit within the introducer sheath 110. For example, once the catheter has reached its destination within the heart chamber, the introducer sheath 110 is retracted from the distal region of the catheter 105 (or the shaft of the catheter extends through the introducer sheath 110), and the electrode deployment mechanism and the electrode assembly can be configured to be in a deployed position. The electrode assembly has a retracted shape when the catheter 105 is in the retracted position and has a deployed shape when the catheter 105 is in the deployed position. In some examples, the electrode assembly has more than two positions.

[0059] In addition, the electrode deployment mechanism in the present disclosure can be deformable such that the electrode deployment mechanism and the electrode assembly can be in a deformed configuration that deviates from the deployed position. The electrode deployment mechanism can be deformed relative to the deployed position. For example, when subjected to a force greater than a threshold force, the electrode deployment mechanism and the electrode assembly in the deployed position can be deformed. In one instance, if the electrode deployment mechanism and the electrode assembly are pressed or pushed against a target tissue (such as the heart wall), the electrode deployment mechanism and the electrode assembly can be deformed. For example, the splines can be made of a deflectable or extensible material or be configured to include yieldable components. In certain examples, the electrode deployment mechanism is elastic and, when the force is removed (such as if the electrode deployment mechanism is moved away from the target tissue), the electrode deployment mechanism returns to the deployed position.

[0060] In one example, multiple electrodes can be formed of a conductive, solid-surface, biocompatible material and spaced apart across an insulator. Each of the multiple electrodes is electrically coupled to a respective elongated lead conductor that extends axially to the proximal end of the catheter. In one example, each of the spaced-apart electrodes corresponds to a separate single lead conductor. In another example, multiple electrodes can be coupled to a single lead conductor. Other configurations can be envisioned. The multiple lead conductors can be insulated from each other within an insulating sheath along the catheter axis, such as using an insulating polymer sheath. The lead conductors can be electrically coupled to a plug in the proximal region of the electroporation catheter 105, such as a plug configured to be mechanically and electrically coupled to an electroporation console 130, for example, directly or via an intermediate electrical conductor (such as a cable).

[0061] The electroporation console 130 includes a controller, such as one or more controllers, processors, or computers, that executes instructions or code (such as processor-executable instructions) from a non-transitory computer-readable medium (such as a memory device or memory) to cause (such as control or perform) aspects of the electroporation catheter system 60. In one example, the electroporation console 130 is configured to provide electrical signals, such as multiple simultaneous or spatio-temporally separated electrical signals, to an electrically connected electroporation catheter 105 that travels along lead conductors to spaced-apart electrodes. The spaced-apart electrodes are configured to generate a selected electric field near the target tissue based on the electrical signals from the electroporation console 130, such as to effect electroporation or mapping.

[0062] The electroporation console 130 can generate electrical signals and select which electrodes in an electrode array will receive the electrical signals. A first electrode or first group of electrodes can be selected as the anode, and a different second electrode or second group of electrodes can be selected as the cathode such that an electric field can be generated between the anode and cathode based on signals (such as pulses) provided from the electroporation console 130 to the electrodes. The console 130 provides electrical pulses of different lengths and amplitudes to the electrodes on the catheter 105. The electrical pulses can be provided as a continuous stream of pulses or multiple individual pulse trains. Pulse parameters of interest include the number of pulses, pulse duty cycle, pulse train spacing, pulse voltage or amplitude including peak voltage, and voltage duration. For example, the console 130 can select two or more electrodes of an electrode assembly and provide pulses to the selected electrodes to generate an electric field between the selected electrodes.

[0063] In ablation mode, the console can select electrodes to provide pulsed field ablation (PFA). For example, PFA can be performed using single-phase and biphasic waveforms. Without being limited by a particular theory, it has been shown that electric field strengths typically in the range of 200 - 250 volts per centimeter (V / cm) within microsecond pulse durations provide reversible electroporation in cardiac tissue. It has been shown that an electric field strength of approximately 400 V / cm provides irreversible electroporation in cardiac tissue of interest (such as target myocardial tissue and endocardial tissue), where it can be demonstrated that red blood cells, vascular smooth muscle tissue, endothelial tissue, nerves, and other non-target adjacent tissues are preserved.

[0064] The electroporation console 130 can also receive electrical signals from electrodes in the electric field, such as electrical signals generated by or in response to the electric field. The electrical signals can indicate parameters of the electric field. The electrical signals can be applied for feedback on the electric field. Measurement or processing of the electrical signals can determine parameters of the electric field, such as the position of the electrodes and the field strength. For example, the electrodes can include: ablation electrodes configured to deliver ablation electric field energy and mapping electrodes for mapping purposes. In some configurations, the mapping electrodes are configured to collect electrical signals that are to be used to generate, via an operatively coupled EAM system 70, and display via an operatively coupled display 92: a detailed three-dimensional geometric anatomical map or representation of a heart chamber, and an electroanatomical map in which cardiac electrical activity of interest is superimposed on the geometric anatomical map. In some examples, the electrodes can operate as ablation electrodes in the ablation mode of the electrophysiology system 50 and as mapping electrodes in the mapping mode of the system 50. The mapping electrodes on the electroporation catheter 105 can measure electrical signals and generate output signals that can be processed by the mapping and navigation controller 90 to generate an electroanatomical map (also referred to as an anatomical map). In some instances, the electroanatomical map is generated prior to ablation to determine the electrical activity of cardiac tissue within a chamber of interest. In some instances, the electroanatomical map is generated after ablation to verify desired changes in the electrical activity of the ablated tissue and chamber. The mapping electrodes can also be used to determine the position of the catheter 105 in the three-dimensional space within the body. For example, when the operator moves the distal end of the catheter 105 within a heart chamber of interest, the boundaries of the catheter movement can be used by the mapping and navigation controller 90 to form an anatomical map of the chamber. The chamber anatomical map can be used to facilitate navigation of the catheter 105 without the use of ionizing radiation (such as using fluoroscopy), and to mark the location of ablation when ablation is complete, in order to guide the spacing of ablation and assist the clinician in ablating the anatomical structure of interest.

[0065] The EAM system 70 is configured to generate anatomical maps for display on the display 92. The EAM system 70 is operable to track the positions of the various components of the electroporation catheter system 60 and generate high-fidelity three-dimensional anatomical and electroanatomical maps of the heart, including portions of the heart (such as a heart chamber of interest) or other structures of interest (such as the sinoatrial node or the atrioventricular node). In one illustrative example, the EAM system 70 can include RHYTHMIA sold by Boston Scientific Corporation TMHDx mapping system. Additionally, the mapping and navigation controller 90 of the EAM system 70 includes one or more controllers, such as a microprocessor or a computer, which run code in a memory to control or execute the functional aspects of the EAM system 70, where the memory can be part of one or more controllers, microprocessors, computers, or part of a memory device accessible via a computer network.

[0066] The EAM system 70 generates a positioning field via the field generator 80 to define a positioning volume around the heart 30, and a position sensor or sensing element on the tracked device (such as the sensor on the electroporation catheter 105) generates an output that can be processed by the mapping and navigation controller 90 to track the sensor and thus the position of the corresponding device within the positioning volume. In the illustrated example, device tracking is achieved using magnetic tracking technology, where the field generator 80 is a magnetic field generator that generates a magnetic field defining the positioning volume, and the position sensor on the tracked device is a magnetic field sensor.

[0067] In other examples, impedance tracking methods can be employed to track the positions of various devices. In such examples, the positioning field is, for example, an electric field generated by an external field generator arrangement (such as surface electrodes), by an in-vivo or intracardiac device (such as an intracardiac catheter), or both. In these examples, the position sensing elements can constitute electrodes on the tracked device, which generate an output received and processed by the mapping and navigation controller 90 to track the positions of the various position sensing electrodes within the positioning volume.

[0068] The EAM system 70 can be equipped with both magnetic tracking capabilities and impedance tracking capabilities. In such examples, the impedance tracking accuracy can be enhanced in some instances by first creating a map of the electric field induced by an electric field generator within the heart chamber of interest using a probe equipped with a magnetic positioning sensor, as can be achieved using the RHYTHMIA HDx TM mapping system. An exemplary probe is the INTELLAMAP ORION TM mapping catheter sold by Boston Scientific Corporation.

[0069] Regardless of the tracking method employed, the EAM system 70 utilizes the position information for various tracked devices, along with the cardiac electrical activity acquired by, for example, the electroporation catheter 105 or another catheter or probe equipped with sensing electrodes, to generate and display via the display 92 a detailed three-dimensional geometric anatomical map or representation of the heart tissue and cavities (such as heart chambers), as well as an electroanatomical map in which the cardiac electrical activity of interest is superimposed on the geometric anatomical map. Additionally, the EAM system 70 can generate graphical representations of the various tracked devices within the geometric anatomical map or electroanatomical map.

[0070] The electroporation catheter system 60 can be combined or integrated with the EAM system 70 to allow a graphical representation of the electric field that can be generated by the electroporation catheter 105 to be visualized on an anatomical map of the patient and, in some instances, on an electroanatomical map of the patient's heart. The integrated system can include the ability to enhance the efficiency of the clinical workflow, including enhancing the visual representation provided to the clinician of the ablation lesion of the portion of the patient's heart created by irreversible electroporation. The integrated system can include: generating a graphical representation of the electric field that can be generated by the electroporation catheter 105, generating an anatomical map (including generating an electroanatomical map), and displaying information related to the location and electric field strength of the electric field that can be generated by the electroporation catheter 105.

[0071] Figure 1 The depiction of the electrophysiological system 50 shown is intended for illustration or general overview of the various components of the system 50 and is not intended to imply that the disclosure is limited to any collection of components or component arrangements. For example, additional hardware components (such as a splitter box or a workstation) can be included in the electrophysiological system 50.

[0072] Figure 2 An example electroporation catheter 200 is shown, which can be an example of the catheter 105 and is used in conjunction with the electrophysiological system 50. The example electroporation catheter 200 includes an elongate catheter shaft 202 and a distal region 204 that is configured to be deployed near the target tissue, such as inside a chamber of the patient's heart. The shaft 202 can extend from an access point within the patient's body to the target tissue and generally defines a longitudinal axis A of the electroporation catheter 200. The longitudinal axis A is presented as a line passing through the centroid of the cross-section of the shaft 202. The shaft 202 terminates distally at a shaft end 206. The distal region 204 in the example includes a plurality of splines 208, such as the splines 208a - 208f shown, to form an electrode deployment mechanism, such as the basket structure 210 in the example. The number of splines in the plurality of splines 208 is presented for illustration, and the basket structure 210 can also include more or fewer than six of the shown splines. Each of the plurality of splines 208 includes a spline proximal end 212, a spline longitudinal portion 214 having a longitudinally extending length, and a spline distal end 216. In this example, the spline proximal end 212 of each of the plurality of splines 208 is attached to the shaft 202 proximal to the shaft end 206. In such examples, the shaft 202 includes a distal basket structure region 218 that is disposed within and terminates within the basket structure 210. The spline distal ends 216 of each of the plurality of splines are coupled together at a distal tip region 220 to form a basket structure distal end 222 and, in this example, form the distal tip 224 of the catheter 200.

[0073] The catheter 200 is shown in an expanded position 226 in which the basket 210 is deployed for surgery. As shown, in the expanded position 226, the spline longitudinal portions 214 are spaced apart from each other and from the distal basket region 218 of the shaft 202. The basket 210 in the expanded position can include an expanded length L and an expanded diameter D and a specific profile. The length of the basket 210 (such as the length L) can be determined based on the distance along the longitudinal axis A between the most proximal end 212 of the spline 208 to the most distal end 216 of the spline 208. The diameter of the basket 210 (such as the diameter D) can be determined based on the maximum distance between the longitudinal portions 214 of the opposing splines 208 along a line generally perpendicular to the axis A. In the expanded position 226, the plurality of splines 208 are spaced apart from each other and form a cavity 228 within the basket 210, and the distal basket region 218 of the shaft 202 is disposed within the cavity 228.

[0074] In this example, the plurality of splines 208 are constructed of a flexible and resilient material so that the catheter 200 can also transition to a collapsed position (not shown) in which the collapsed length of the basket structure in this example is greater than L and the collapsed diameter of the basket structure is less than D. In the collapsed position, the splines 208 can contact each other and the distal basket structure region 218 of the shaft 201. In one example, the catheter 200 is placed in the collapsed position with an introducer sheath (such as sheath 106) positioned over the splines 208 and the catheter is in a non-operational mode. If the basket structure 210 is extended from the introducer sheath, or the introducer sheath is retracted back from the basket structure 210, the basket structure can assume the deployed position 226 and be deployed in an operational mode.

[0075] In some examples, the catheter 200 includes a proximal end (not shown) and the catheter 200 may include a handle assembly in the proximal region of the catheter 200, which is coupled to the shaft 202 to allow the clinician to manipulate the catheter 200 during the electroporation ablation procedure. In addition, the catheter may include a navigation sensor (not shown) on or near the distal region 204, which may be disposed within the shaft 202, such as within the distal basket structure region 218. The navigation sensor may collect sensor data and may be electrically coupled to the proximal end of the catheter via a lead to provide an electrical signal to the EAM system 70 regarding the location of the navigation sensor in the electrophysiology system 50.

[0076] The catheter 200 includes an electrode assembly 230 having a plurality of spaced-apart electrodes 232. The plurality of electrodes 232 may be formed of a conductive, solid-surface, biocompatible material. In the illustrated example, at least some of the plurality of electrodes 232 are annular electrodes disposed around the shaft 204 and the spline 208, although other configurations are contemplated, and the shaft 202 and the spline 208 are spaced apart across an insulator. For example, the shaft 202 and the spline 208 may be covered with an electrically insulating material. Each of the plurality of electrodes 232 is electrically coupled to a respective elongated lead conductor disposed within the shaft 204, and the lead conductor extends along the shaft 202 to the proximal end of the catheter. In one example, each of the spaced-apart electrodes 232 corresponds to a separate single lead conductor. In another example, the plurality of electrodes 232 may be coupled to a single lead conductor. Other configurations are contemplated. The plurality of lead conductors may be insulated from each other within an insulating sheath along the shaft 202, such as with an insulating polymer sheath. The lead conductors may be electrically coupled to a plug in the proximal region of the catheter 200, such as a plug configured to be mechanically and electrically coupled, for example, directly or via an intermediate electrical conductor (such as a cable), to an electroporation console 130. In one example, the electroporation console 130 is configured to provide electrical signals, such as a plurality of simultaneous or spatio-temporally separated electrical signals, to the electrically connected electroporation catheter 200, which travel along the lead conductors to the spaced-apart electrodes 232. The spaced-apart electrodes 232 are configured to generate a selected electric field proximal to the target tissue based on the electrical signals from the electroporation console 130, such as to effect electroporation or mapping.

[0077] The electrode assembly 230 includes a plurality of spline electrodes 234 that are spaced apart from each other in the deployed position and are disposed on the spline longitudinal portions 214 of at least some of the plurality of splines 208. In the illustrated example, each of the splines 208a - 208f includes a set of spaced - apart spline electrodes 236. For example, spline 208a includes set of spline electrodes 236a. Spline 208b includes set of spline electrodes 236b. Spline 208c includes set of spline electrodes 236c. Spline 208d includes set of spline electrodes 236d. Spline 208e includes set of spline electrodes 236e. Spline 208f includes set of spline electrodes 236f. The number of spline electrodes in each of the sets of spline electrodes 236a - 236f can vary and can be different from the four as shown. Additionally, the spacing between the spline electrodes along the longitudinal portion 214 can vary and can be different from the substantially equidistant spacing as shown. In one example, the sets of spaced - apart spline electrodes 236 are fixed to the respective splines 208 such that each spline electrode in each set of spline electrodes is spaced apart from each electrode in the same set of spline electrodes, and no spline electrode in the set of spline electrodes 236 contacts another spline electrode in the same set of spline electrodes. Further, each spline electrode of the plurality of spline electrodes 234 is spaced apart from each spline electrode in the deployed state, and no spline electrode of the plurality of spline electrodes contacts another spline electrode in the deployed state. However, in a non - operating mode of the catheter 200, such as the retracted position, it should be envisioned that the electrodes can contact each other.

[0078] The electrode assembly 230 may include additional electrodes, including in some examples a measurement reference electrode 240 or a measurement electrode 240 and a shaft electrode 242. The measurement electrode 240 is disposed within the basket structure 210, such as within the cavity 228 when the catheter 200 is in the deployed position, to protect the measurement electrode 240 from contacting the target tissue when the catheter 200 is deployed within the heart in an operative mode. In this example, the measurement electrode 240 is included on the distal basket region 218 of the shaft 204 such that the measurement electrode is within the cavity 228 when the catheter 200 is in the deployed position. As shown, an example measurement electrode 240 is disposed on the shaft end 206 as a cap structure that includes an annular portion around the longitudinal sides of the shaft end 206 and a main surface on the distal tip of the shaft end. Additionally or alternatively to the measurement electrode 240, in some examples, the electrode assembly 230 may include a distal reference electrode 244 or a distal electrode 244, which may be coupled to the distal tip region 220, such as the distal end 222 of the basket structure. In this example, when the catheter 200 is in the deployed position, the distal electrode 244 is coupled to the distal end 222 of the basket structure to be within the basket structure 210, such as within the cavity 228. In the illustrated example, the distal electrode 244 includes a proximally facing main surface that faces the main surface of the measurement electrode 240 when used in combination with the measurement electrode 240. The spacing along the axis A between the measurement electrode 240 and the distal electrode 244 may be a distance d. Additionally or alternatively to the measurement electrode 240, in some examples, the electrode assembly 230 may include a shaft electrode 242 disposed on the shaft 202 in a region proximal to the basket structure 210. An example catheter 200 includes a plurality of shaft electrodes, such as a pair of shaft electrodes 242, 246. The shaft electrodes 242, 246 in this example are annular electrodes. This example shows the measurement electrode 240 and the shaft electrodes 242, 246 secured to the shaft 202 and thus in a fixed spatial relationship during the operative mode of the catheter 200. The basket structure 210 and the plurality of splines 208 are deflectable relative to each other and to the shaft 202, and thus the plurality of spline electrodes 234 and the distal electrode 244 are movable relative to each other and relative to the measurement electrode 240 and the shaft electrodes 242, 246.

[0079] Figures 3A to 3C Illustrated is the catheter 200 in various operative modes when deployed within an organ, such as a chamber of a patient's heart, where like parts include like reference numerals. Figure 3AShows the catheter 200 in the deployed position 300 (which is the first operating mode), adjacent to the heart wall 302. In the deployed position 300, the basket structure 210 is not subjected to force or the force on the basket structure 210 does not exceed the threshold force that causes bending or deformation of the splines in the plurality of splines 208. For example, if the basket structure 210 is away from the heart wall 302 in the chamber or hardly contacts the heart wall 302, the catheter 200 can assume the deployed position 300. In the deployed position 300, the basket structure 210 includes a diameter D1 and a length L1, which correspond to Figure 2 the diameter D and length L of . In the example, the measurement electrode 240 is spaced apart from the distal electrode 244 by a distance d1. For illustrative purposes, the shape of the spline 208 is in the form of a Bezier curve - a parametric curve with a series of control points that defines a generally smooth and continuous arc extending from the proximal end 212 to the distal end 216 - where the characteristic of the Bezier curve is alpha α1 at the proximal end 212. By way of illustration, example reference dimensions include a length L1 of 15 mm, a diameter D1 of 10 mm, a distance D1 of 3 mm, and an alpha α1 of 0.80.

[0080] Figure 3BThe catheter 200 is shown in a first deformed state 310 (which is also an operating mode in which the electrodes 232 of the electrode assembly 230 are spaced apart from each other), adjacent to the heart wall 302. In the first deformed state 310, the basket structure 210 is adjacent to the heart wall 302 and is subjected to a force along the longitudinal axis A in the direction towards the distal tip 224, the force exceeding the threshold force that causes the splines in the plurality of splines 208 to bend or deform from the deployed position 300. For example, when the clinician begins to push the basket structure against the heart wall 302, the catheter 200 can assume the first deformed state 310. In the first deformed state 310, the basket structure 210 includes a diameter D2 that is greater than the diameter D1 of the deployed position 300 and a length L2 that is less than the length L1 of the deployed position 300. In an example, the measurement electrode 240 and the distal electrode 244 are spaced apart by a distance d2, which is less than the d1 of the deployed position 300. The characteristic of the Bezier curve of the spline 208 in the first deformed state is alpha α2 at the proximal end 212, where alpha α2 is greater than alpha α1 of the deployed position 300. By way of illustration, example reference dimensions include a length L2 of 14 mm, a diameter D2 of 11 mm, a distance d2 of 2 mm, and an alpha α2 of 0.85. Here, some of the electrodes 232 in the plurality of electrodes (such as the electrodes opposite each other on the spline 208) are closer together or closer to the measurement electrode 240 than in the deployed position 300. Additionally, some of the electrodes 232 in the plurality of electrodes (such as the electrodes on different splines 208a - 208f) are farther apart than in the deployed position 300. The positions of at least some of the electrodes 208 in the electrode array in the first deformed state 310 are spatially different from the deployed position 300.

[0081] Figure 3CThe catheter 200 is shown in a second deformed state 320 (which is also an operating mode in which the electrodes 232 of the electrode assembly 230 are spaced apart from each other) adjacent to the heart wall 302. In the second deformed state 320, the basket structure 210 is also adjacent to the heart wall 302 and experiences a force along the longitudinal axis A in the direction towards the distal tip 224 that exceeds the threshold force causing further bending or deformation of the splines in the plurality of splines 208 from the first deformed state 310. For example, when the clinician continues to push the basket structure against the heart wall 302 after making a strong contact with a force sufficient to bend the splines 208, the catheter 200 can assume the second deformed state 310. In the second deformed state 320, the basket structure 210 includes a diameter D3 that is greater than the diameter D2 of the first deformed state 310 and a length L3 that is less than the L2 of the first deformed state 310. In the example, the measurement electrode 240 and the distal electrode 244 are spaced apart by a distance d3, which is less than the d2 of the first deformed state 310. The characteristic of the Bezier curve of the spline 208 in the second deformed state 320 is alpha α3 at the proximal end 212, where alpha α3 is greater than alpha α2 of the first deformed state 310. By way of illustration, example reference dimensions include a length L3 of 13 mm, a diameter D3 of 12 mm, a distance d3 of 1 mm, and an alpha α3 of 0.90. Here, some of the plurality of electrodes 232 (such as the electrodes opposite each other on the spline 208) are closer together or closer to the measurement electrode 240 than in the first deformed state 310. Additionally, some of the plurality of electrodes 232 (such as the electrodes on different splines 208a - 208f) are farther apart than in the first deformed state 310. The positions of at least some of the electrodes 208 in the electrode array in the second deformed state 320 are spatially different from the deployed position 300 or the first deformed state 310.

[0082] An electric field is generated in the electrode assembly 220, and signals received from the electrode 232 in the electric field can be measured and used to determine or judge the position of the electrode 232 of the electrode assembly 230 in space. For example, the electric field can be measured to determine parameters of the electric field, and the parameters of the electric field can be used to determine or judge the position of the electrode 232 of the electrode assembly 230 in space relative to a reference point on the catheter 200 (such as the measurement electrode 240, the shaft electrode 242 or other reference points). In one example, the first electrode group of the electrode assembly 230 can be used to measure the electric field generated by the electrode assembly 230, and the determined electrode position can be used to determine whether the basket structure 210 is in the deployed position 300 or in a deformed state relative to the deployed position 300 (such as states 310, 320). In one example, the first electrode group can include the measurement electrode 240, the shaft electrodes 242, 246, the measurement electrode 240 and the shaft electrodes 242, 246, or another electrode in the electrode assembly. The determination that the basket structure 210 is in a deformed state can be used as an inferential determination of contact between the basket structure 210 and the heart wall or other boundaries, and the determination that the basket structure 210 is in the deployed position can be used as an inferential determination that the basket structure is not in contact with or is hardly in contact with tissue. Based on such inferential determinations, together with the navigation information from the catheter 200, the electroanatomical map can be updated using the indication at the boundary of the position of the basket structure 210 by the catheter 200.

[0083] Figure 4 A functional block diagram of an example controller 400 that can be used in an example electrophysiological system 50 is shown, such as the controller of the example electroporation catheter system 60 or the controller of the example EAM system 70, which can include the controller of the electroporation console 130 or the mapping and navigation controller 90, respectively. In other examples, the controller 400 can be the controller of the integrated electroporation catheter system 60 and EAM system 70, or the controller for the electroporation catheter system 60 and EAM system 70.

[0084] The controller 400 can be implemented to indicate contact of the catheter 105 with the heart (such as with the wall of a chamber of the heart) and to indicate the degree or amount of contact based on deformation of the catheter. In some examples, the controller 400 can also be implemented to indicate where in the heart the catheter contacts tissue. In some examples, the controller can be implemented to indicate the amount of tissue dilation or compression after contact with the catheter has been established. The amount of deformation of the catheter can be used to generate a more accurate or a corrected electroanatomical map of the heart. The deformation of the catheter 105 can be an inferential measurement of force or contact with tissue.

[0085] The controller 400 may include a processor 402 and a memory 404. The memory 404 stores processor-executable instructions 406. In one example, the processor-executable instructions may be in the form of a program, such as a computer program or an application. The processor 402 may execute the instructions 406, which may be included in configuring the controller 400. In one example, the controller 400 may be implemented to include a computing device, such as a laptop computer, a workstation, a desktop computer, a tablet computer, or a smart phone. In such examples, the controller 400 may include additional components, such as a display, a touch screen, a speaker, or other output devices, a keyboard or other input devices, or communication circuitry, such as a computer network adapter. The controller 400 may be implemented in a variety of architectures, and components such as the processor 402 and the memory 404 may be distributed at various locations.

[0086] In one example, the processor 402 may include multiple main processing cores to run an operating system and execute general tasks on an integrated circuit. The processor 402 may also include built-in logic or programmable functional units, also on the same integrated circuit with a heterogeneous instruction set architecture. In addition to the multiple general-purpose main processing cores and application processing units, the controller 400 may include other devices or circuits, such as a graphics processing unit or a neural network processing unit, which may include a heterogeneous or homogeneous instruction set architecture with main processing cores. For example, the controller 400 may be used to perform other tasks, such as in the case where the computing device includes a resonant sound amplification device.

[0087] The memory 404 is an example of a computer storage medium. Computer storage media include RAM, ROM, EEPROM, flash memory or other memory technologies, CD-ROM, digital versatile disc (DVD) or other optical storage, magnetic tape cartridges, magnetic tape, magnetic disk storage or other magnetic storage devices, USB flash drives, flash memory cards or other flash memory storage devices, or other storage media that can be used to store the required information and can be accessed by the processor 402. Any such computer storage medium may be part of the controller 300 and implemented as the memory 404. The memory 404 is a non-transitory, processor-readable storage device. Thus, a propagated signal by itself does not qualify as a storage medium or a memory 304.

[0088] The processor-executable instructions 406 may include, for example, computer code or machine-usable instructions, such as program components that can be executed by the processor 402 associated with the controller 400. The program components may be programmed using any number of different programming environments, including various languages, development toolkits, or frameworks. Some or all of the program components may alternatively or additionally be implemented in hardware.

[0089] The controller 400 can be configured to receive inputs or information from the electrophysiology system 50, such as inputs from the electroporation catheter system 60 and the EAM system 70 (including the electroporation console 130 and the mapping and navigation controller 90), for storage in the memory 404 and use by the instructions 406. For example, the controller 400 can receive an input representing an anatomical map of the heart or cardiac mapping data 408 from, for example, the EAM system 70. The cardiac mapping data 408 can include data representing a geometric anatomical map of the heart and an electroanatomical map of the heart. The cardiac mapping data 408 can be stored in the memory 404. Additionally, the controller can receive electric field parameter data 410 from, for example, the electroporation catheter system 60, and the electric field parameter data 410 can be stored in the memory 404. The electric field parameter data 410 can include electric field generation parameter data 412 and include electric field measurement parameter data 414. The inputs and information can include user-generated information to add or annotate the data 408, 410, 412.

[0090] The electric field generation parameter data 412 can include data about parameters of an electric field to be generated or produced by the catheter 105 in a patient's heart as provided. In this example, the intensity of the electric field to be generated by the catheter is lower than the intensity for irreversible electroporation. In one example, the controller 400 can cause the electroporation catheter system 60 to generate an electric field. For example, the controller 400 determines the parameters of the electric field and provides a signal regarding the electric field generation parameter data 412 to the electroporation catheter system 60 to generate an electric field in the catheter 105 in response to the electric field generation parameter data 412. In another example, the electroporation catheter system 60 generates an electric field and provides the electric field generation parameter data 412 to the controller 400. The electric field generation parameter data 412 can include such parameters as data about: the intensity of the electric field intended to be generated by the catheter 105, the intensity of the signal provided to the electrode assembly, the configuration of the electrodes in the electrode assembly (such as whether the electrodes in the electrode assembly are configured as anodes or cathodes). In other examples, the electric field generation parameter data 412 can include information about the catheter 105, such as the configuration and spacing of the electrodes on the catheter 105. Examples of the configuration and spacing of the electrodes on the catheter 105 can include information about: the spacing and size of the electrodes in the electrode assembly in the deployed position, the size of the electrodes, and whether the electrodes are applied as measurement electrodes 240 or shaft electrodes 242, 246 (such as on the catheter 200), the nominal spacing of the electrodes on the splines in the deployed position and the spacing of the splines in the deployed position relative to each other, and the distance between the electrodes, such as the distance between the measurement electrode 240 in the deployed position and the distal electrode, and the distance between the measurement electrode 240 and any shaft electrodes 242, 246 on the catheter shaft 202.

[0091] The electric field measurement parameter data 414 includes data regarding parameters of the electric field measured or determined by the catheter 105 in the patient's heart in response to the generated electric field. The electric field measurement parameter data 414 may include such parameters as data regarding: the intensity of the electric field measured by the catheter 105, the intensity of the signals provided to the electrode assembly (such as the electrical parameters of the signals received from the respective electrodes of the electrode assembly), the configuration of the electrodes in the electrode assembly (such as whether the electrodes in the electrode assembly are configured as anodes or cathodes or such as measurement electrodes or shaft electrodes on the catheter 200). The electric field measurement parameter data 414 may include other data from the electric field measured by the catheter 105 in the patient's heart. For example, when immersed in the electric field, the measurement electrodes 240, the distal electrodes 244, and the shaft electrodes 242, 246 may be used to provide signals that can be interpreted as electric field measurement parameter data 414. In one example, the measured electrical signal corresponds to a voltage. The measurement electrode 240 is disposed within the basket structure 210 so as not to contact the heart tissue, which is beneficial in providing a reference point as well as providing the electric field measurement parameter data 414. In other examples, the spline electrodes 236 or a collection of spline electrodes may be designated to provide signals that can be interpreted as electric field measurement parameter data 414.

[0092] The controller 400 may receive an input representing the relative position of the catheter 105 (such as the position within the patient's heart or within the tracking system) as catheter position data 416. In one example, a position sensor or sensing element on the electroporation catheter 105 may generate an output that can be processed by the controller 400 to track the sensor and thus the position of the catheter 105 within the positioning volume. For example, the position sensor or sensing element on the catheter 105 may include a magnetic device or an electrode.

[0093] Based on the electric field generation parameter data 412 (including the electric field measurement parameter data 414) and the catheter position data 416, the controller can determine information such as the positions of the electrodes 232 relative to each other and the position of the catheter. In one example, the electric field generation parameter data 412 includes the electric field measurement parameter data 414 and the catheter position data 416, and the controller can determine information such as the position of a measurement electrode (such as the measurement electrode 240) that does not contact the tissue within the heart chamber. Additionally, the position of the distal electrode 244 relative to the measurement electrode 240 can be determined. Further, the respective positions of the electrodes on the spline, such as the positions of the spline electrode set 236 relative to each other. Still further, the respective positions of the spline electrode groups can be determined relative to other spline electrode groups, such as the spline electrode group 236a relative to other spline electrode groups 236b - 236f. Using measurement signals from the electrodes sufficient to provide the electric field measurement parameter data 414, the position shape of the basket structure 210 can be determined, and the amount of force for deforming the basket structure can be determined, from a force below a threshold force to a force that places the catheter in a non-operational state.

[0094] The controller 400 is configured to generate visualization content 420, which may include information related to how much the catheter has been deformed from the deployed position. In one example, the controller 400 is configured to generate a deformation amount in the visualization content 420, such as using a deformation gradient on a display. In another example, the controller 400 is configured to generate a real-time rendering of the deformation in the catheter in the visualization content 420, such as highlighting the deformed portion of the catheter relative to the deployed position. In yet another example, the controller 400 is configured to generate an update in the cardiac mapping in the graphical display in the visualization content 420 in combination with the cardiac mapping data 408, and store such information in the memory 404.

[0095] Figure 5Process 500 shows the process of configuring a controller (such as controller 400) while performing electroporation of target tissue (such as in a chamber of a patient's heart). In one example, the controller is implemented as part of an EAM system 70 and is operably coupled to an electroporation catheter system 60. Process 500 includes: at 502, configuring the controller to generate an electric field in the catheter. For example, the catheter can be an example of catheter 105 (such as catheter 200) and can include an electrode assembly 230 having a plurality of spaced-apart electrodes 232 disposed on a plurality of splines 208 to generate an electric field, wherein the splines 208 can be configured to be in an expanded position 300 such that the plurality of spaced-apart electrodes are in a selected spatial relationship. The splines 208 are deformable relative to the expanded position 300 when subjected to force and can assume a deformed state, such as deformed states 310, 320. In one example, the catheter includes a shaft 200 having a distal region 204, and the plurality of splines 208 form a basket structure 210 in the expanded position 300, wherein each of the plurality of splines 208 includes a proximal end 212 and a distal end 216, and the basket structure 210 is coupled to the distal region 204, wherein the distal ends 216 of the splines 208 form a distal tip region 222 of the basket structure 210. Controller 400 is configured to receive and process information about the generated electric field using electric field generation parameter data 412.

[0096] At 504, controller 400 is configured to measure an electrical signal received from an electrode among the plurality of spaced-apart electrodes 232 in response to the electric field, wherein the electrical signal indicates a parameter of the electric field. In one example of 504, controller 400 is configured to measure a plurality of electrical signals received from the plurality of spaced-apart electrodes 232 in response to the electric field, the plurality of electrical signals indicating parameters of the electric field. In one example, the plurality of electrodes includes a measurement electrode 240 disposed within the basket structure 210 and configured not to contact tissue (such as heart wall 302) when the catheter 200 is in the expanded position 300, which can be used to measure the electrical signal. In one example, the plurality of electrodes includes a distal reference electrode (such as distal electrode 244) disposed within the basket structure 210 and coupled to the distal tip region 222 of the basket structure 210, which can be used to measure the electrical signal. Additionally, the plurality of electrodes 232 includes shaft electrodes 242 or 246 disposed on the distal region of the shaft and proximal to the basket structure, which can be used to measure the electrical signal. For example, the controller is configured to receive and process the measured electrical signals as electric field measurement parameter data 414.

[0097] The deformation of the splines is determined based on the determination of the positions of the plurality of electrodes from the measured electrical signals. In one example, the change over time of the measured electrical signals is used to determine the deformation. In another example, based on the measured signals, it can be determined whether the basket structure is in the deployed position or in a deformed but operable state. For example, the deformation of the splines is determined based on the distance between the plurality of spaced-apart electrodes from the measured electrical signals. From the determined deformation, it can be determined that the basket structure is in contact with a structure such as the heart wall. In one example, the determination of the deformation includes the determination of the amount of deformation (such as the degree of deformation) of the splines relative to the deployed position. From the degree of deformation, the amount of force applied to the heart wall using the basket structure can be determined.

[0098] At 506, the controller 400 is configured to determine the deformation of the splines relative to the deployed position based on the measured electrical signals. In one example, the controller can apply the electric field generation parameter data 412 regarding the catheter (such as the configuration and spacing of the electrodes on the catheter in the deployed position) to determine whether the catheter is in a deformed state. Examples of the configuration and spacing of the electrodes on the catheter 200 can include information regarding: the spacing and size of the electrodes in the electrode assembly in the deployed position 300, the size of the electrodes, and whether the electrodes are applied as measurement electrodes 240 or shaft electrodes 242, 246 (such as on the catheter 200), the nominal spacing of the electrodes on the splines in the deployed position and the spacing of the splines relative to each other in the deployed position, and the distance between the electrodes, such as the distance between the measurement electrode 240 and the distal electrode 244 in the deployed position, and the distance between the measurement electrode 240 and any shaft electrodes 242, 246 on the catheter shaft 202.

[0099] In one example, the controller 400 is configured to determine deformation at 506 by selecting a reference electrode from among a plurality of electrodes 232. In one example, the reference electrode can be any one or more of the plurality of electrodes. For example, the reference electrode can be the measurement electrode 240, which can provide a robust measurement because it is disposed within the basket structure and is configured not to contact tissue when the catheter is in the deployed position and in many deformation states. From the measured electrical signals (such as the electric field measurement parameter data 414), the controller is configured to determine the relative spatial position of each of the plurality of electrodes relative to the reference electrode. The controller can continuously determine the relative spatial position of the electrodes and determine whether there is a change in the relative spatial position. The controller can cycle through selected electrode pairs to determine deformation. If the change in the relative spatial position exceeds a selected threshold amount, deformation of the basket structure can be determined. In one example, the measurement electrode 240 and the distal electrode 244 are used as reference electrodes. Additionally, the determination that the measurement electrode 240 and the distal electrode 244 are in contact with each other can be used to determine deformation. In yet another example, the shaft electrode can be used as a reference electrode in a separate or secondary determination of deformation.

[0100] In one example of the determination of deformation at 506, the controller is configured to apply the measured electrical signals to a look-up table that has a set of signals corresponding to deformation states or amounts of deformation. For example, the look-up table can be populated with nodes of signals corresponding to the forces or deformation states and amounts of deformation applied during the test phase of the system. During the ablation process, the measured electrical signals are input into the look-up table and a corresponding output is provided. Measured electrical signals that do not match the nodes can be converted to a determination of deformation based on nearby nodes, along with an adjustment to the corresponding amount of deformation. In one example, the system can apply multiple look-up tables and access the corresponding look-up table based on other parameters of the system as determined from the electric field generation parameter data 412, such as, for example, a specific look-up table for multiple catheters, a specific look-up table for the electric field intensity applied during mapping, a specific look-up table for the configuration of the electrodes used to perform the mapping, and other look-up tables.

[0101] In one example, the determination of deformation includes, for example, a determination of tissue dilation after contact with tissue or deformation of the splines has been determined. The electrode signals from the measured signals at 504, the catheter position data 416, and the catheter shape information from the determination of deformation at 506 can be applied to determine tissue dilation. As the tissue dilates, the tissue will contact more of the electrodes 232, independent of compression of the basket structure or a decrease in the distance d between the measurement electrode 240 and the distal electrode 244. The amount of tissue dilation can be estimated based on the amount of change in the electrodes in contact with the tissue and the amount of change in the catheter position adjusted for the basket structure shape deformation.

[0102] At 508, the controller 400 is configured to generate visualization content based on deformation. The visualization content can be on a graphical display and can be supplementary or overlaid on an electroanatomical map, and uses catheter position data 416 to determine the position of the catheter. In some examples, the visualization content can include real-time changes. For example, the controller is configured to generate a visualization of a gradient based on the amount of deformation of the spline relative to the deployed position. The gradient can be a bar graph on the graphical display. The controller can also be configured to generate a visualization of the deformation of the spline on the graphical display. The visualization can highlight the deformed spline among multiple splines in the visualization of the deformation of the spline. The visualization of the deformation of the spline can also be rendered on the electroanatomical map, such as using cardiac mapping data 408 and catheter position data 416. In one example, the controller is configured to determine the deformation of the spline relative to the deployed position substantially in real time.

[0103] In one example, the process 500 can be implemented as a set of processor-executable instructions (such as instructions 406) stored in a non-transitory memory (such as memory 404) to be executed by the processor 402 to configure the controller 400. The instructions for implementing the process 500 can be configured to receive information, such as retrieving cardiac mapping data 408, electric field parameter data 410 (including electric field measurement parameter data 414), and catheter position data 416 from the memory 404. Additionally, the instructions for implementing the process 500 can be configured to annotate, adjust, or write to the cardiac mapping data 408 and generate visualization content, such as visualization content 420 on a graphical representation display.

[0104] Without departing from the scope of the present disclosure, various modifications and additions can be made to the exemplary embodiments discussed. For example, while the embodiments described above relate to specific features, the scope of the present invention also includes embodiments with different combinations of features and embodiments that do not include all of the described features. Accordingly, the scope of the present invention is intended to cover all such alternatives, modifications, and variations, as well as all equivalents thereof, that fall within the scope of the claims.

Claims

1. A system for facilitating ablation in a patient's heart, the system comprising: A catheter including an electrode assembly having a plurality of spaced-apart electrodes disposed on a plurality of splines to generate an electric field in the heart, the splines being configurable to an expanded position in which the plurality of spaced-apart electrodes are in a selected spatial relationship, and wherein the splines are deformable relative to the expanded configuration when subjected to a force; And A controller configured to: Measure an electrical signal received from an electrode among the plurality of spaced-apart electrodes in response to the electric field, the electrical signal indicating a parameter of the electric field; And Determine a deformation of the splines relative to the expanded position based on the measured electrical signal.

2. The system according to claim 1, wherein The deformation of the splines is determined based on a determination of the positions of the plurality of electrodes from the measured electrical signal.

3. The system according to any one of claims 1 to 2, wherein, The deformation of the splines is determined based on the distance between the plurality of spaced-apart electrodes from the measured electrical signal.

4. The system according to any one of claims 1 to 3, wherein, The controller is configured to measure a plurality of electrical signals received from the plurality of spaced-apart electrodes in response to the electric field, the plurality of electrical signals indicating a parameter of the electric field.

5. The system according to any one of claims 1 to 3, wherein, The determination of the deformation includes a determination of the amount of deformation of the splines relative to the expanded position.

6. The system according to claim 5, wherein, The controller is configured to generate a visualization of a gradient based on the amount of deformation of the splines relative to the expanded position.

7. The system according to any one of claims 5 to 6, wherein The controller is configured to generate a visualization of the deformation of the splines.

8. The system according to claim 7, wherein, The controller is configured to highlight a deformed spline among the plurality of splines in the visualization of the deformation of the splines.

9. The system according to any one of claims 7 to 8, wherein The controller is configured to generate a visualization of the deformation of the splines on an electroanatomical map of the heart.

10. The system according to any one of claims 1 to 9, wherein, The controller is configured to determine the deformation of the splines relative to the expanded position substantially in real time.

11. The system according to any one of claims 1 to 10, wherein The determination of the deformation includes a determination of tissue dilation.

12. The system according to any one of claims 1 to 11, wherein, The catheter includes a shaft having a distal region, and the plurality of splines form a basket structure in the expanded position, wherein each of the plurality of splines includes a proximal end and a distal end, the basket structure being coupled to the distal region, wherein the distal ends of the splines form a distal tip region of the basket structure.

13. The system according to claim 12, wherein, The plurality of electrodes include measurement electrodes disposed within the basket structure and configured not to contact tissue when the catheter is in the expanded position.

14. The system according to claim 13, wherein, The plurality of electrodes include distal indifferent electrodes disposed within the basket structure and coupled to the distal tip region.

15. The system according to any one of claims 12 to 14, wherein, The plurality of electrodes include shaft electrodes disposed on the distal region of the shaft and proximal to the basket structure.

16. A system for facilitating ablation, the system comprising: A catheter including an electrode assembly having a plurality of spaced-apart electrodes disposed on a plurality of splines to generate an electric field, the splines being configurable to an expanded position in which the plurality of spaced-apart electrodes are in a selected spatial relationship, and wherein the splines are deformable relative to the expanded position when subjected to a force; And A controller operatively coupled to the electrode assembly and configured to: Measuring an electrical signal received by an electrode from among the plurality of spaced-apart electrodes in response to the electric field, the electrical signal indicative of a parameter of the electric field; And Determining a deformation of the splines relative to the deployed position based on the measured electrical signal.

17. The system according to claim 16, wherein, The catheter includes a shaft having a distal region, and the plurality of splines form a basket-like structure in the deployed position, wherein each of the plurality of splines includes a proximal end and a distal end, the basket-like structure is coupled to the distal region, and wherein the distal ends of the splines form a distal tip region of the basket-like structure.

18. The system according to claim 17, wherein, The plurality of electrodes includes measurement electrodes disposed within the basket-like structure and configured not to contact tissue when the catheter is in the deployed position.

19. The system according to claim 18, wherein, The measurement electrodes provide the electrical signal.

20. The system according to claim 18, wherein, The plurality of electrodes includes distal reference electrodes disposed within the basket-like structure and coupled to the distal tip region, and the controller is configured to determine a distance between the measurement electrodes and the distal reference electrodes.

21. The system according to claim 16, wherein, The deformation of the splines is determined based on a determination of the position of each of the plurality of electrodes from the measured electrical signal.

22. The system according to claim 16, wherein The determination of the deformation includes a determination of an amount of deformation of the splines relative to the deployed position.

23. The system according to claim 22, wherein, The controller is configured to determine an amount of force applied to the splines based on the determination of the amount of deformation.

24. The system according to claim 16, wherein The controller is configured to generate a visualization based on the deformation.

25. The system according to claim 24, wherein, The controller is configured to generate a visualization of a gradient based on an amount of deformation of the splines relative to the deployed position.

26. The system according to claim 24, wherein, The controller is configured to highlight deformed splines among the plurality of splines.

27. The system according to claim 24, wherein, The controller is configured to generate a visualization of the deformation on an electroanatomical map of the heart.

28. An electroporation catheter for tissue, comprising: An elongate shaft having a distal region; And An electrode assembly operatively coupled to the distal region, the electrode assembly having a plurality of spaced-apart electrodes disposed on a plurality of splines to generate an electric field, the splines configurable in a deployed position in which the plurality of spaced-apart electrodes are in a selected spatial relationship, and wherein the splines are deformable relative to the deployed position when subjected to force; Wherein the plurality of splines form a basket-like structure that defines a cavity in the deployed position, wherein each of the plurality of splines includes a proximal end and a distal end, the basket-like structure is coupled to the distal region, and wherein the distal ends of the splines form a distal tip region of the basket-like structure, the shaft having a distal basket-like structure region that extends into the cavity and terminates within the cavity; and Wherein the plurality of electrodes includes measurement electrodes disposed on the distal basket-like structure region of the shaft within the basket-like structure and configured not to contact the tissue when the splines are in the deployed position.

29. The catheter according to claim 28, wherein, The plurality of electrodes includes distal reference electrodes disposed within the basket-like structure and coupled to the distal tip region, the distal reference electrodes being spaced apart from the shaft and the measurement electrodes.

30. The catheter according to claim 29, wherein, The plurality of electrodes includes shaft electrodes disposed on the distal region of the shaft and proximal to the basket-like structure.

31. A method for facilitating ablation in a patient's heart, the method comprising: generating an electric field in the heart using a catheter, the catheter including an electrode assembly having a plurality of spaced-apart electrodes disposed on a plurality of splines to generate the electric field, the splines being configurable to an expanded position in which the plurality of spaced-apart electrodes are in a selected spatial relationship, and wherein the splines are deformable relative to the expanded position when subjected to a force; and measuring an electrical signal received at an electrode from the plurality of spaced-apart electrodes in response to the electric field, the electrical signal indicating a parameter of the electric field; determining a deformation of the splines relative to the expanded position based on the measured electrical signal, wherein the deformation of the splines is determined based on determining the position of each of the plurality of electrodes relative to the electrode assembly from the measured electrical signal.

32. The method according to claim 31 further comprises: determining an amount of force applied to the catheter based on the determination of the amount of deformation.

33. The method according to claim 31 further comprises: generating a visualization based on the deformation on a graphical display.

34. The process according to claim 33, wherein, generating the visualization includes: generating a visualization of the deformation of the splines on an electroanatomical map of the heart.

35. The method according to claim 31, wherein determining the deformation further includes: determining an amount of tissue dilation based on the determined amount of contact of the plurality of electrodes with the heart, the determined position of the catheter within the heart, and the determined amount of deformation.

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