Ablation electrode assembly including enhanced position sensing capability

Abstract

The disclosed technology includes an electrode assembly including an electrode body including a top surface and a bottom surface. The electrode body may be configured to deliver ablation energy to tissue at least through the top surface. The electrode assembly may also include a coil disposed proximate the bottom surface. The coil may be configured to generate a voltage when subjected to a magnetic field. The electrode assembly may include a member disposed proximate to the coil and including a high permeability material.

Description

[0001] Cross - reference to related patent applications

[0002] This application claims the benefit and priority of U.S. Provisional Patent Application No. 63 / 611,547, filed on December 18, 2023 (Attorney Docket No.: BIO6838USPSP1-253757.000387), under 35 U.S.C. § 119(e), the entire content of which is incorporated herein by reference. Technical Field

[0003] The present invention generally relates to ablation electrode assemblies, and more particularly to ablation electrode assemblies that include electromagnetic coils and high magnetic permeability materials to provide magnetic-based position sensing. Background Art

[0004] Myocardial injection catheters are often used to map and ablate myocardial tissue. Myocardial injection catheters typically include an end effector having one or more electrodes configured to receive electrical signals for mapping from tissue and / or deliver ablation energy to tissue for ablation. To ensure that the electrodes are properly positioned for mapping or ablation, some end effectors include position sensing, such as electromagnetic position sensing or active current location (ACL) technology.

[0005] Electromagnetic position sensing typically utilizes electromagnetic coils disposed on or near the end effector, which are configured to generate a current when subjected to a magnetic field induced by a magnetic field generator positioned external to the patient. However, many electromagnetic sensors require coils with multiple windings to ensure that the electromagnetic sensor has sufficient sensitivity to detect the electromagnetic field. Unfortunately, increasing the number of windings increases the size of the electromagnetic sensor. As will be appreciated, for cardiovascular surgery, it is desirable for the end effector to be small enough. Accordingly, there is a need in the art for methods to increase the sensitivity of electromagnetic sensors while also reducing the size of the end effector. The techniques disclosed herein address these problems. Summary of the Invention

[0006] According to one example of the present invention, an electrode assembly is provided that includes an electrode body having a top surface and a bottom surface. The electrode body may be configured to deliver ablation energy to tissue at least through the top surface. The electrode assembly may further include a coil disposed near the bottom surface. The coil may be configured to generate a voltage when subjected to a magnetic field. The electrode assembly may include a member disposed near the coil and including a high magnetic permeability material.

[0007] The disclosed technology may include a medical device that includes a flexible shaft extending along a longitudinal axis and a plurality of ridges disposed at a distal end of the flexible shaft. The plurality of ridges may be configured to bend radially outward from the longitudinal axis and transition between an expanded configuration and a collapsed configuration. The medical device may also include a plurality of electrode assemblies attached to the plurality of ridges. Each electrode assembly of the plurality of electrode assemblies may include an electrode body having a top surface and a bottom surface. The electrode body may be configured to deliver ablation energy to tissue at least through the top surface. The electrode assembly may include a coil disposed near the bottom surface. The coil may be configured to generate a voltage when subjected to a magnetic field. The electrode assembly may include a member disposed near the coil and including a high magnetic permeability material.

[0008] Additional features, functions, and applications of the disclosed technology are discussed in more detail herein. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] Figure 1 is a schematic illustration of a medical system according to an example of the disclosed technology;

[0010] Figure 2A is a schematic illustration of a basket catheter in an expanded configuration according to an example of the disclosed technology;

[0011] Figure 2B is a schematic illustration of a basket catheter in a collapsed configuration according to an example of the disclosed technology;

[0012] Figure 3A is a perspective view of an electrode assembly according to an example of the disclosed technology;

[0013] Figure 3B is a top perspective view of an electrode assembly according to an example of the disclosed technology;

[0014] Figure 4A is a bottom view of an electrode assembly according to an example of the disclosed technology;

[0015] Figure 4B is according to an example of the disclosed technology Figure 4A cross-sectional view of an electrode assembly;

[0016] Figure 4C is a cross-sectional view of an electrode assembly according to another example of the disclosed technology;

[0017] Figure 4D is a cross-sectional view of an electrode assembly according to yet another example of the disclosed technology;

[0018] Figure 4E is a cross-sectional view of an electrode assembly according to still another example of the disclosed technology;

[0019] Figure 4Fis a cross-sectional view of an electrode assembly according to another example of the disclosed technology;

[0020] Figure 5A is a perspective view of an electrode according to another example of the disclosed technology;

[0021] Figure 5B is of an Figure 5A electrode according to an example of the disclosed technology;

[0022] Figure 5C is a front view of an electrode according to yet another example of the disclosed technology;

[0023] Figure 5D is of an Figure 5C electrode according to an example of the disclosed technology;

[0024] Figure 5E is a perspective view of an electrode according to still another example of the disclosed technology; and

[0025] Figure 5F is of an Figure 5E electrode according to an example of the disclosed technology; DETAILED DESCRIPTION

[0026] The disclosed technology includes a plurality of electrode assemblies that are coupled to a plurality of ridges to form a basket catheter disposed at a distal end of a flexible shaft. Each electrode assembly may include an electrode body designed to deliver ablation energy to tissue. Each electrode assembly may also include an electromagnetic coil attached to the electrode body, the electromagnetic coil being configured to generate a current when subjected to an electromagnetic field generated by an electromagnetic field generator. The real-time position of the distal end of the catheter can be tracked based on the current generated in the electromagnetic coil. By disposing the electromagnetic coil on the electrode body, the overall size of the end effector can be reduced, and multiple electromagnetic coils (for a catheter having multiple electrode assemblies) can be utilized to improve the accuracy of position sensing. To further increase the sensitivity of the electromagnetic coil, the electrode assembly may also include a high magnetic permeability material disposed near the electromagnetic coil.

[0027] The following detailed description should be read with reference to the accompanying drawings, in which like numerals in different drawings identify the same elements. The drawings (not necessarily to scale) depict selected examples and are not intended to limit the scope of the invention. The detailed description illustrates the principles of the invention by way of example and not by way of limitation. This description will clearly enable one of ordinary skill in the art to make and use the invention and describes several embodiments, adaptations, variations, alternatives, and uses of the invention, including what is presently believed to be the best mode of carrying out the invention.

[0028] As used herein, the term "about" or "approximately" with respect to any numerical value or range indicates a suitable dimensional tolerance that allows a set of parts or components to achieve its intended purpose as described herein. More specifically, "about" or "approximately" can refer to a range of values of ±20% of the recited value. For example, "about 90%" can refer to a range of values from 71% to 110%. In addition, as used herein, the terms "patient", "recipient", "user", and "subject" refer to any human or animal subject, and are not intended to limit the system or method to human use, but the use of the subject invention in human patients represents a preferred embodiment. Similarly, the term "proximal" refers to a position closer to the operator or physician, while "distal" refers to a position farther from the operator or physician.

[0029] As discussed herein, the vasculature of a "patient", "recipient", "user", and "subject" can be that of a human or any animal. It should be understood that the animal can be of any suitable type, including but not limited to mammals, veterinary animals, livestock animals, or pet animals, etc. For example, the animal can be an experimental animal (e.g., rats, dogs, pigs, monkeys, etc.) specifically selected to have certain characteristics similar to humans. It should be understood that the subject can be, for example, any suitable human patient.

[0030] As discussed herein, a "physician" can include a doctor, surgeon, technician, scientist, operator, or any other individual or delivery instrument associated with delivering a multi-electrode catheter for treating drug-refractory atrial fibrillation to a subject.

[0031] As discussed herein, when referring to the devices and corresponding systems of the present disclosure, the term "ablation" refers to components and structural features configured to reduce or prevent the generation of unstable cardiac signals in cells by using non-thermal energy (such as reversible or irreversible electroporation (IRE), interchangeably referred to as pulsed electric field (PEF) and pulsed field ablation (PFA) in the present disclosure) or thermal energy (such as radiofrequency (RF) ablation or cryoablation). "Ablation" as used throughout the present disclosure, when referring to the devices and corresponding systems of the present disclosure, refers to thermal or non-thermal ablation of cardiac tissue for certain conditions, including but not limited to arrhythmia, atrial flutter ablation, pulmonary vein isolation, supraventricular tachycardia ablation, and ventricular tachycardia ablation. The term "ablation" also includes known methods, devices, and systems for achieving various forms of ablation of body tissue understood by those skilled in the relevant art.

[0032] As discussed herein, the terms "tubular" and "tube" are to be understood broadly and are not limited to structures that are right circular cylinders or have a fully circular cross-section or a uniform cross-section along their entire length. For example, a tubular structure is typically illustrated as a structure that is substantially a right circular cylinder. However, without departing from the scope of the present disclosure, a tubular structure may have a tapered or curved outer or inner surface.

[0033] Reference Figure 1 , which shows an exemplary catheter-based electrophysiological mapping and ablation system 10. System 10 includes a plurality of catheters that are inserted by a physician 24 through the vasculature of a patient 23 via the skin into the chambers or vascular structures of the heart 12. Typically, a delivery sheath catheter is inserted into the left atrium or right atrium near a desired location within the heart 12. Then, a plurality of catheters may be inserted into the delivery sheath catheter in order to reach that desired location. The plurality of catheters may include catheters dedicated to sensing intracardiac electrogram (IEGM) signals, catheters dedicated to ablation, and / or catheters dedicated to both sensing and ablation. To sense the IEGM, the physician 24 contacts the distal end 28 of the catheter 14 with the heart wall for sensing a target site within the heart 12. The end effector of the mapping catheter may include a basket catheter, a planar catheter, a focused catheter, a balloon catheter, etc. For ablation, the physician 24 will similarly bring the distal end of the ablation catheter to the target site for ablation (as Figure 1 illustrated in the drawing). Similarly, the end effector of the ablation catheter may include a basket catheter, a planar catheter, a focused catheter, a balloon catheter, etc.

[0034] Catheter 14 is an exemplary catheter that includes one and preferably a plurality of electrode assemblies 26 that are optionally distributed on a plurality of ridges 22 at the distal end 28 and are configured to deliver ablation energy to tissue. Catheter 14 may additionally include a position sensor 29 embedded in or near the distal end 28 for tracking the position and orientation of the distal end 28. Optionally and preferably, the position sensor 29 is a magnetic-based position sensor that includes three magnetic coils for sensing three-dimensional (3D) position and orientation.

[0035] The magnet-based position sensor 29 can operate with the positioning pad 25, which includes a plurality of magnetic coils 32 configured to generate a magnetic field in a predetermined workspace. The real-time position of the distal end 28 of the catheter 14 can be tracked based on the magnetic field generated by the positioning pad 25 and sensed by the magnet-based position sensor 29. Details of magnet-based position sensing techniques are described in U.S. Pat. Nos. 5,391,199, 5,443,489, 5,558,091, 6,172,499, 6,239,724, 6,332,089, 6,484,118, 6,618,612, 6,690,963, 6,788,967, 6,892,091, the entire contents of each of which are incorporated herein by reference as if fully set forth herein.

[0036] The system 10 includes one or more electrode patches 38 positioned for contact with the skin of the patient 23 to establish a position reference for impedance-based tracking of the positioning pad 25 and the electrode assembly 26. For impedance-based tracking, current is directed toward the electrode assembly 26 and sensed at the electrode skin patches 38 such that the position of each electrode can be triangulated via the electrode patches 38. Details of impedance-based position tracking techniques are described in U.S. Pat. Nos. 7,536,218, 7,756,576, 7,848,787, 7,869,865, and 8,456,182, the entire contents of each of which are incorporated herein by reference as if fully set forth herein.

[0037] The recorder 11 displays the electrogram 21 captured using the body surface ECG electrodes 18 and the intracardiac electrogram (IEGM) captured using the electrode assembly 26 of the catheter 14. The recorder 11 can include pacing capabilities for pacing the heart rhythm and / or can be electrically connected to an independent pacemaker.

[0038] The system 10 can include an ablation energy generator 50 adapted to conduct ablation energy to one or more electrodes at the distal tip of a catheter configured for ablation. The energy generated by the ablation energy generator 50 can include, but is not limited to, radiofrequency (RF) energy or pulsed field ablation (PFA) energy (including monopolar or bipolar high voltage DC pulses that can be used to effect irreversible electroporation (IRE)) or a combination thereof.

[0039] The Patient Interface Unit (PIU) 30 is an interface configured to establish electrical connectivity between a catheter, electrophysiology equipment, a power source, and a workstation 55 for controlling the operation of the system 10. The electrophysiology equipment of the system 10 can include, for example, a plurality of catheters, positioning pads 25, body surface ECG electrodes 18, electrode patches 38, an ablation energy generator 50, and a recorder 11. Optionally and preferably, the PIU 30 further includes processing capabilities for performing real-time calculations of the position of the catheter and for performing ECG calculations.

[0040] The workstation 55 includes a memory, a processor unit with a memory or storage device loaded with appropriate operating software, and user interface capabilities. The workstation 55 can provide a plurality of functions, optionally including: (1) performing three-dimensional (3D) modeling of the endocardial anatomy and rendering a model or anatomical map 20 for display on a display device 27; (2) displaying the activation sequence (or other data) compiled from the recorded electrograms 21 as representative visual markers or images superimposed on the rendered anatomical map 20 on the display device 27; (3) displaying the real-time position and orientation of a plurality of catheters within the heart chambers; and (4) displaying sites of interest, such as where ablation energy has been applied, on the display device 27. A commercial product embodying the elements of the system 10 can be CARTO TM 3System is available from Biosense Webster, Inc., 31 Technology Drive, Suite 200, Irvine, CA 92618, USA.

[0041] Figure 2A is a schematic illustration showing a perspective view of a medical probe 200 having an end effector including a distal tip 28, the distal tip being a basket assembly that is in an expanded form when unconstrained (such as by being pushed out of the lumen 80 of the tubular shaft 82 at the distal end 85 as depicted in Figure 2B ) within the tubular shaft lumen 80. Figure 2B shows the basket assembly in a collapsed form within the tubular shaft 82. In the expanded form ( Figure 2A ), the ridges 22 bend radially outward along the longitudinal axis 86, and in the collapsed form ( Figure 2B ), the ridges are generally constrained by the inner wall of the tubular shaft 82 along the longitudinal axis 86 of the tubular shaft 82.

[0042] As Figure 2AAs shown, the basket assembly 28 (which may be interchangeably referred to herein as the "distal end") includes a plurality of flexible ridges 22 that are formed at the end of the flexible shaft 84 and are connected at both ends. During a medical procedure, the physician 24 can deploy the basket assembly 28 by extending the flexible shaft 84 from the tubular shaft 82 to move the basket assembly 28 out of the tubular shaft 82 and into an expanded form. The ridges 22 can have an oval (e.g., circular) or rectangular (which can appear flat) cross-section and comprise a flexible elastic material (e.g., a shape memory alloy such as nitinol, also known as NiTiNOL) that forms struts, as will be described in more detail herein.

[0043] In the example described herein, the electrode assembly 26 can be configured to deliver ablation energy (RF and / or IRE) to tissue in the heart 12 or other parts of the patient 23's body. In addition to delivering ablation energy using the electrode assembly 26, the electrode assembly can also be used to measure physiological properties such as local surface potential (e.g., IEGM signals) at corresponding locations on tissue in the heart 12. The electrode assembly 26 can be biased such that a larger surface area of the electrode body of the electrode assembly 26 faces outward from the basket assembly 28, such that the electrode assembly 26 delivers a greater amount of electrical energy outward away from the basket assembly 28 (i.e., toward the heart 12 tissue) rather than inward toward the longitudinal axis 86 of the basket assembly 28.

[0044] The basket assembly 28 can include a rod 96 that extends longitudinally from the distal end 90 of the flexible shaft 84 toward the distal end 212 of the basket assembly 28. The disclosed technology can include a flushing system that delivers a flushing fluid to the spray ports 98. For example, the rod 96 can include a plurality of spray ports 98, where each given spray port 98 can be angled to direct the flushing fluid to a given electrode assembly 26 or to tissue in the heart 12. The electrode assembly 26 can be cooled by aligning the flushing fluid via the spray ports 98 with the portion of the electrode assembly 26 on the inner side of the ridges 22. The basket assembly 28 can include a central intersection 211 that is located at the point where the ridges 22 converge near the distal end 212.

[0045] Reference Figure 3A and Figure 3B, the electrode assembly 26 may have an electrode body 330 having a top surface 332 and a bottom surface 334. The top surface 332 may be configured to face outward from the basket assembly 28 to contact tissue, while the bottom surface 334 may be configured to face inward toward the longitudinal axis 86 of the basket assembly 28 such that the bottom surface 334 is less likely to contact tissue. The electrode body 330 may be configured to deliver ablation energy to tissue at least through the top surface 332. The top surface 332 of the electrode body 330 may be substantially flat or planar. Alternatively, the top surface 332 may be circular or have a contoured profile. The bottom surface 334 of the electrode body 330 may be substantially flat or planar. In some examples, the flat portion of the bottom surface 334 may include a larger surface area compared to the flat portion of the top surface 332.

[0046] The electrode body 330 may include a lumen 336 extending through the electrode body 330. The lumen 336 may be configured to receive a ridge 22 of an end effector, such as the ridge 22 of the basket assembly 28, as Figure 2A depicted. The ridge 22 may be disposed along the longitudinal axis L-L of the lumen 336. The electrode assembly 26 may be fixed to the ridge 22 of the basket assembly 28. The fixation of the electrode assembly 26 to the ridge 22 may include a coupling between the ridge 22 and the inner surface of the lumen 336. For example, the electrode assembly 26 may be crimped, glued, fastened, or otherwise coupled to the ridge 22 to prevent the electrode assembly 26 from sliding along the length of the ridge 22.

[0047] Referring Figures 4A to 4C , the electrode assembly 26 may include an electrode body 330, a coil 440 disposed near the bottom surface 334 of the electrode body 330, and a member 450 disposed near the bottom surface 334 of the electrode body 330. The electrode body 330 may be configured to deliver ablation energy to tissue through the top surface 332. The member 450 may include a high magnetic permeability material. The coil 440 may be configured to generate a current when subjected to a magnetic field. In some examples, the coil 440 may include a single-axis sensor (SAS) or a triaxial sensor (TAS). The coil 400 may include a conductive material that is wound into a coil and disposed on the bottom surface 334, or a coil formed as a flexible circuit, and the flexible circuit may be attached to the bottom surface 334. The coil 440 may include an electrical lead 442 for conducting the current induced on the coil 440 to the patient interface unit 30. As will be appreciated, by attaching the coil 440 to the electrode body 330, it is possible to detect the position of each individual electrode of the basket assembly 28 (or at least each electrode in the electrode assembly 26 that includes the coil 440). In this way, the physician 24 can more accurately determine the position of the electrode assembly 26 before applying ablation energy to the tissue.

[0048] The component 450 can be a high-permeability material that is disposed near the coil 440 to help increase the sensitivity of the coil 440. When the coil 440 includes, for example, a uniaxial sensor, the component 450 can help enhance the electromagnetic field near the uniaxial coil. The high-permeability material can include mu-metal, nanocrystalline metal, 99.95% pure iron, or a combination thereof. The component 450, for example, can have a relative permeability of about 50,000 to about 200,000. By placing the component 450 near the coil 440, the component 450 will provide a path for the magnetic field to pass through the component 450 to the coil 440 to help increase the effect of the magnetic field on the coil 440, thereby increasing the sensitivity of the coil 440 in the magnetic field. The high-permeability characteristic of the component 450 provides a low-reluctance path for the magnetic flux. In this way, the disclosed technology can help increase the magnetic field near the coil 440, thereby inducing a current on the coil 440 for magnetic-based position sensing.

[0049] Reference Figure 4A , the electrode assembly 26 can include an electrode body 330 having a bottom surface 334. The electrode assembly 26 can include a coil 440 disposed near the bottom surface 334 of the electrode body 330. The electrode assembly 26 can include a component 450 also disposed near the bottom surface 334 of the electrode body 330. In some examples, the component 450 can be disposed on the bottom surface 334 of the electrode body 330, and the coil 440 can be disposed on the bottom surface of the component 450. Alternatively, the coil 440 can be disposed on the bottom surface 334 of the electrode body 330 and the component 450 can be disposed on the bottom surface of the coil 440.

[0050] Figure 4B Shown Figure 4A A cross-sectional view of the electrode assembly 26 depicted in. The electrode assembly 26 can include an electrode body 330 having a top surface 332, a bottom surface 334, and a lumen 336 disposed through the electrode body 330. As shown, the electrode assembly 26 can include a component 450 disposed on the bottom surface 334 of the electrode body 330, which is a high-permeability material. The coil 440 can be disposed on the bottom side of the component 450 such that the component 450 is disposed between the bottom surface 334 of the electrode body 330 and the coil 440.

[0051] Reference Figure 4C , in another example of the disclosed technology, the coil 440 can be disposed on the bottom surface 334 of the electrode body 330. Additionally, the component 450 can be disposed on the bottom surface of the coil 440 such that the coil 440 is disposed between the bottom surface 334 of the electrode body 330 and the component 450.

[0052] Figure 4D and Figure 4EA cross-sectional view of electrode assembly 26 is shown, which includes an insulating material 460 disposed on the bottom surface 334 of electrode body 330. The insulating material 460 may be disposed on the bottom surface 334 of electrode body 330 to form an insulating layer on the bottom surface 334 of electrode body 330 to electrically insulate electrode body 330 from coil 440 and member 450. In this way, the insulating material 460 can prevent interference between coil 440 and the electrode during ablation and / or positioning operations.

[0053] Go to Figure 4D , the insulating material 460 may be disposed between coil 440 and the bottom surface 334 of electrode body 330. Member 450 may be disposed below coil 440 such that coil 440 is disposed between insulating material 460 and member 450. On the other hand, Figure 4E Depicts insulating material 460 disposed between member 450 and the bottom surface 334 of electrode body 330. Coil 440 may be disposed below member 450 such that member 450 is disposed between insulating material 460 and coil 440.

[0054] Figure 4F A cross-sectional view of electrode assembly 26 is shown, which includes a member 450 disposed within electrode body 330. Electrode body 330 may be configured to deliver ablation energy to tissue through top surface 332. Member 450 may include a high magnetic permeability material at least partially disposed within electrode body 330. Member 450 may be disposed within electrode body 330 near the bottom surface 334 of electrode body 330, and coil 440 may be disposed on the bottom surface 334 of electrode body 330. In this way, member 450 can be disposed near coil 440 and help improve the sensitivity of coil 440 when subjected to a magnetic field as described herein.

[0055] Figures 5A to 5F Depicts a variant of the electrode body that can be used with the disclosed technology. That is, the features described above can be applied to various other electrode body configurations, including but not limited to Figures 5A to 5F those electrode bodies shown in. In addition, although Figures 5A to 5F each electrode depicted in includes lumens 336A, 336B, 336C configured to receive ridges (e.g., ridge 22) for attaching electrode bodies 330A, 330B, 330C to the ridge, it should be understood that other types of attachment mechanisms are envisioned. For example, the disclosed technology may include electrode assemblies that are attached to the ridge by curling, fastening, gluing the electrode assembly to the ridge, etc. rather than by inserting the ridge through lumens 336A, 336B, 336C.

[0056] Figure 5A and Figure 5BDepicts a variant form of electrode body 330A, which includes a top surface 332A, a bottom surface 334A, and an inner lumen 336A, and is configured to deliver ablation energy to tissue at least through the top surface 332A of the electrode body 330A. Refer to Figure 5A and Figure 5B , the electrode body 330A can be curved such that the top surface 332A includes a convex curvature while the bottom surface 334A includes a convex curvature. This configuration can allow for an increased surface area at the top surface 332A relative to the bottom surface 334A, where ablation energy is applied to tissue. The electrode body 330A can include an inner lumen 336A that passes through it and along the longitudinal axis L-L of the electrode body 330A, and the inner lumen is configured to receive the ridges of a basket catheter. The electrode body 330A can also include a groove 338A to accommodate the wiring that provides electricity for ablation. The groove 338A can be formed by an extension of the inner lumen 336A.

[0057] Figure 5C and Figure 5D Depicts a variant form of electrode body 330B, which includes a top surface 332B, a bottom surface 334B, and an inner lumen 336B, and is configured to deliver ablation energy to tissue at least through the top surface 332B of the electrode body 330B. Refer to Figure 5C and Figure 5D , the electrode body 330B can be an elongated body including a substantially elliptical shape. The top surface 332B and the bottom surface 334B can be substantially flat. The electrode body 330B can include an inner lumen 336B that passes through it and along the longitudinal axis L-L of the electrode body 330B, and the inner lumen is configured to receive the ridges of a basket catheter. The electrode body 330B can also include a groove 338B to accommodate the wiring that provides electricity for ablation. The groove 338B can be formed by an extension of the inner lumen 336B.

[0058] Figure 5E and Figure 5F Depicts a variant form of electrode body 330C, which includes a top surface 332C, a bottom surface 334C, and an inner lumen 336C, and is configured to deliver ablation energy to tissue at least through the top surface 332C of the electrode body 330C. Refer to Figure 5C and Figure 5D, the electrode body 330C may include a top surface 332C having a convex curvature. The electrode body 330C may taper from the top surface 332C toward the bottom surface 334C. Relative to the bottom surface 334C, this configuration may allow for an increased surface area at the top surface 332C where ablation energy is applied to tissue. The electrode body 330C may include a lumen 336C that passes through it and along the longitudinal axis L-L of the electrode body 330C, and the lumen is configured to receive a ridge of a basket catheter. The electrode body 330B may further include holes 338C to accommodate wiring that provides electricity for ablation. The holes 338C may be additional through-holes that extend through the electrode body 330C. The holes 338C may extend parallel to the lumen 336C.

[0059] Examples of materials that are ideally suited to form the electrode bodies described herein include gold, platinum, and palladium (and their corresponding alloys). These materials also have high thermal conductivity, which allows the minimum amount of heat generated on tissue (i.e., by ablation energy delivered to the tissue) to be conducted through the electrode body to the bottom surface of the electrode (i.e., the portion of the electrode on the inner side of the ridge), and then to the blood pool in the heart 12. Additionally, a conductive polymer material may be disposed along the outer surface of the electrode body.

[0060] The high magnetic permeability materials described herein with respect to the present technology can be made of any material, and materials with higher magnetic permeability are more suitable. Magnetic field lines preferentially pass through materials with high magnetic permeability. In various embodiments of the present technology, Mu metal, amorphous metal alloys (also known as metallic glass alloys), nanocrystalline metals, or 99.95% pure iron can be used. Mu metal and a particular branch of amorphous alloys (METGLAS is a registered trademark of Metglas, Inc., Conway, South Carolina) are both particularly suitable for use with the components of the present disclosure. Compared to air with a magnetic permeability equal to one (i.e., μ = 1), it has been found that Mu metal has a relative magnetic permeability of approximately 50,000, while 99.95% pure iron has a relative magnetic permeability of approximately 200,000.

[0061] The disclosed technology described herein can be further understood in accordance with the following terms:

[0062] Clause 1: An electrode assembly, comprising: an electrode body including a top surface and a bottom surface, the electrode body being configured to deliver ablation energy to tissue at least through the top surface; a coil disposed near the bottom surface, the coil being configured to generate a voltage when subjected to a magnetic field; and a component disposed near the coil and including a high magnetic permeability material.

[0063] Clause 2: The electrode assembly according to Clause 1, wherein the member is disposed between the coil and the electrode body, and the member is attached to the bottom surface of the electrode body.

[0064] Clause 3: The electrode assembly according to Clause 2, further comprising an insulating material disposed between the member and the bottom surface of the electrode body.

[0065] Clause 4: The electrode assembly according to Clause 1, wherein the coil is disposed between the member and the electrode body, and the coil is attached to the bottom surface of the electrode body.

[0066] Clause 5: The electrode assembly according to Clause 4, further comprising an insulating material disposed between the coil and the bottom surface of the electrode body.

[0067] Clause 6: The electrode assembly according to Clause 1, wherein the member is at least partially disposed within the electrode body.

[0068] Clause 7: The electrode assembly according to any one of the preceding clauses, wherein the electrode body further comprises a lumen extending therethrough, the lumen being configured to receive a ridge of an end effector.

[0069] Clause 8: The electrode assembly according to any one of the preceding clauses, wherein the coil comprises a single axis sensor (SAS).

[0070] Clause 9: The electrode assembly according to any one of the preceding clauses, wherein the coil comprises a flexible circuit.

[0071] Clause 10: The electrode assembly according to any one of the preceding clauses, wherein the high permeability material comprises Mu metal.

[0072] Clause 11: The electrode assembly according to any one of the preceding clauses, further comprising a conductive polymer material disposed along an outer surface of the electrode body.

[0073] Clause 12: A medical device, comprising: a flexible shaft extending along a longitudinal axis; a plurality of ridges disposed at a distal end of the flexible shaft, the plurality of ridges being configured to bend radially outward from the longitudinal axis and transition between an expanded configuration and a collapsed configuration; a plurality of electrode assemblies attached to the plurality of ridges, each electrode assembly of the plurality of electrode assemblies comprising: an electrode body including a top surface and a bottom surface, the electrode body being configured to deliver ablation energy to tissue at least through the top surface; a coil disposed near the bottom surface, the coil being configured to generate a voltage when subjected to a magnetic field; and a member disposed near the coil and comprising a high permeability material.

[0074] Clause 13: For the medical device according to Clause 12, the member is disposed between the coil and the electrode body, and the member is attached to the bottom surface of the electrode body.

[0075] Clause 14: For the medical device according to Clause 13, it further includes an insulating material disposed between the member and the bottom surface of the electrode body.

[0076] Clause 15: For the medical device according to Clause 12, the coil is disposed between the member and the electrode body, and the coil is attached to the bottom surface of the electrode body.

[0077] Clause 16: For the medical device according to Clause 15, it further includes an insulating material disposed between the coil and the bottom surface of the electrode body.

[0078] Clause 17: For the medical device according to Clause 12, the member is at least partially disposed in the electrode body.

[0079] Clause 18: For the medical device according to any one of Clauses 12 to 17, the electrode body further includes a lumen extending therethrough, and the lumen is configured to receive a ridge of an end effector.

[0080] Clause 19: For the medical device according to any one of Clauses 12 to 18, the coil includes a flexible circuit.

[0081] Clause 20: For the medical device according to any one of Clauses 12 to 19, wherein the high magnetic permeability material includes Mu metal.

[0082] Clause 21: For the medical device according to any one of Clauses 12 to 20, it further includes a conductive polymer material disposed along the outer surface of the electrode body.

[0083] Clause 22: For the medical device according to any one of Clauses 12 to 21, the coil includes a single axis sensor (SAS).

[0084] The above embodiments are cited by way of example, and the present invention is not limited to the content specifically shown and described above. On the contrary, the scope of the present invention includes combinations and sub - combinations of the various features described above, as well as their variations and modifications, which will occur to those skilled in the art upon reading the above description and which are not disclosed in the prior art.

Claims

1. An electrode assembly, comprising: an electrode body comprising a top surface and a bottom surface, the electrode body being configured to deliver ablative energy to tissue at least through the top surface; a coil disposed proximate the bottom surface, the coil configured to generate a voltage when subjected to a magnetic field; and A member is disposed adjacent to the coil and includes a high magnetic permeability material. 2 . The electrode assembly according to claim 1 , the member is disposed between the coil and the electrode body, the member being attached to the bottom surface of the electrode body. 3 . The electrode assembly according to claim 2 , further comprising an insulating material disposed between the member and the bottom surface of the electrode body. 4 . The electrode assembly according to claim 1 , the coil is disposed between the member and the electrode body, the coil being attached to the bottom surface of the electrode body. 5 . The electrode assembly of claim 4 , further comprising an insulating material disposed between the coil and the bottom surface of the electrode body. The electrode assembly according to claim 1 , wherein the member is at least partially disposed in the electrode body.

7. The electrode assembly of claim 1, the electrode body further comprising a lumen extending therethrough, the lumen configured to receive a ridge of an end effector.

8. The electrode assembly of claim 1, the coil comprising a single axis sensor (SAS).

9. The electrode assembly of claim 1, the coil comprising a flexible circuit.

10. The electrode assembly according to claim 1, wherein: The high magnetic permeability material includes Mu metal.

11. The electrode assembly of claim 1, further comprising a conductive polymer material disposed along an outer surface of the electrode body.

12. A medical device comprising: a flexible shaft extending along a longitudinal axis; a plurality of ridges disposed at a distal end of the flexible shaft, the plurality of ridges configured to bend radially outward from the longitudinal axis and to transition between an expanded configuration and a collapsed configuration; a plurality of electrode assemblies attached to the plurality of ridges, each electrode assembly of the plurality of electrode assemblies comprising: an electrode body comprising a top surface and a bottom surface, the electrode body being configured to deliver ablative energy to tissue at least through the top surface; a coil disposed proximate the bottom surface, the coil configured to generate a voltage when subjected to a magnetic field; and A member is disposed adjacent to the coil and includes a high magnetic permeability material. 13 . The medical device according to claim 12 , the member is provided between the coil and the electrode body, the member being attached to the bottom surface of the electrode body.

14. The medical device of claim 13, further comprising an insulating material disposed between the member and the bottom surface of the electrode body. 15 . The medical device according to claim 12 , the coil is disposed between the member and the electrode body, the coil being attached to the bottom surface of the electrode body. 16 . The medical device of claim 15 , further comprising an insulating material disposed between the coil and the bottom surface of the electrode body.

17. The medical device of claim 12, wherein the member is at least partially disposed in the electrode body.

18. The medical device of claim 12, the electrode body further comprising a lumen extending therethrough, the lumen configured to receive a spine of an end effector.

19. The medical device of claim 12, the coil further comprising a flexible circuit.

20. The medical device according to claim 12, wherein: The high magnetic permeability material includes Mu metal.

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