Pulsed field ablation devices and related methods

Abstract

Disclosed is a pulsed field ablation actuator comprising: (a) an electrode comprising an electrode surface for delivering an electrical current to anatomical tissue; and a deformable insulator selectively covering the electrode surface, the deformable insulator configured to deform when contacted by anatomical tissue to expose the electrode surface. Methods and apparatus for performing electroporation as well as other forms of ablation performed concurrently with electroporation are also disclosed.

Description

[0001] Cross-reference to related applications This application claims the rights of the following U.S. provisional patent applications: U.S. Provisional Patent Application No. 63 / 504,210, filed May 25, 2023, entitled “PULSED FIELD ABLATION APPARATUS AND RELATED METHODS”; U.S. Provisional Patent Application No. 63 / 506,898, filed June 8, 2023, entitled “PULSED FIELD ABLATION APPARATUS AND RELATED METHODS”; and U.S. Provisional Patent Application No. 63 / 506,900, filed June 8, 2023, the disclosure of each of which is incorporated herein by reference in its entirety. Technical Field

[0002] This disclosure relates to ablation devices, and more particularly to ablation systems and devices configured to perform pulsed field ablation, their components, and related methods. Background Technology

[0003] This disclosure contemplates the use of ablation systems configured to perform pulsed field ablation (“PFA”) in a variety of medical and surgical procedures. Generally, PFA systems can be used to ablate target cells while limiting potential collateral damage to non-target tissues. PFA typically involves applying a high-voltage electrical pulse to the target tissue. This pulse generates a high-intensity electric field that disrupts the integrity of cell membranes in the target tissue. Consequently, within a short timeframe (e.g., days to weeks), cells die, resulting in damage within the target tissue.

[0004] This disclosure contemplates the use of PFA to ablate cardiac tissue for the treatment of arrhythmias. In some cases, certain known PFA techniques, such as catheter-based devices, may produce suboptimal results. For example, this disclosure contemplates the possibility that it may be difficult to maintain the desired contact pressure between the catheter-based device and the internal cardiac wall, potentially resulting in inaccurate positioning and / or less durable damage than desired.

[0005] While known PFA systems have been used to perform some cardiac ablation procedures, particularly endocardial ablation (e.g., on the inner surface of the heart), improvements to the construction and operation of PFA systems and devices may benefit users (e.g., physicians and surgeons) and patients. This disclosure includes various improvements that can enhance the construction, operation, and use of PFA systems and devices, including embodiments suitable for epicardial ablation (e.g., on the outer surface of the heart and / or penetrating tissue surfaces). Summary of the Invention

[0006] A first aspect of the invention is to provide a pulsed field ablation actuator comprising: (a) an electrode including an electrode surface for delivering current to anatomical tissue; and (b) a deformable insulator selectively covering the electrode surface, the deformable insulator being configured to deform upon contact with anatomical tissue to expose the electrode surface.

[0007] In a more detailed embodiment of the first aspect, the deformable insulator includes a slit at least partially occupied by an electrode. In yet another more detailed embodiment, the slit extends longitudinally along a major dimension of the deformable insulator, and the electrode extends longitudinally within the slit for a substantial portion of its length. In a further detailed embodiment, the pulsed field ablation actuator also includes a rigid backing to which the electrode and the deformable insulator are mounted. In yet another more detailed embodiment, the deformable insulator is mounted to the rigid backing using a movable hinge. In a more detailed embodiment, the deformable insulator is embedded within the rigid backing. In a more detailed embodiment, the deformable insulator includes a raised feature configured to concentrate contact forces arising from contact with anatomical tissue and to accelerate deformation of the deformable insulator. In yet another more detailed embodiment, the raised feature includes a plurality of raised features, wherein at least two of the plurality of raised features are on opposite sides of the electrode. In yet another more detailed embodiment, the plurality of raised features includes longitudinal ribs, and the longitudinal ribs extend generally parallel to the electrode.

[0008] In yet another, more detailed embodiment of the first aspect, the deformable insulator includes an elastomer. In yet another, more detailed embodiment, the elastomer includes silicone. In a further detailed embodiment, the electrode is segmented into a plurality of electrodes, and the deformable insulator is segmented into a plurality of deformable insulator segments, each of the plurality of electrodes including an electrode surface selectively covered by at least one of the plurality of deformable insulator segments, and only those deformable insulator segments that are in contact with anatomical tissue are deformed to expose those electrodes covered by the contacted plurality of deformable insulator segments. In a still further detailed embodiment, the deformable insulator is segmented into a plurality of deformable insulator segments, the electrode surface is selectively covered by at least one of the plurality of deformable insulator segments, and only those deformable insulator segments that are in contact with anatomical tissue are deformed to expose those aspects of the electrode surface covered by the contacted plurality of deformable insulator segments. In a more detailed embodiment, the pulsed field ablation actuator further includes a cryogenic conduit configured to supply cryogenic fluid to the cryogenic tissue contact portion. In a more detailed embodiment, the cryogenic tissue contact portion includes the electrode surface of an electrode. In another more detailed embodiment, the pulsed field ablation actuator further includes a radiofrequency electrode adapted to deliver radiofrequency energy to the anatomical tissue. In yet another more detailed embodiment, the radiofrequency electrode is selectively covered by a deformable insulator.

[0009] A second aspect of the invention is to provide a method for performing pulsed field tissue ablation, the method comprising: (a) repositioning a pulsed field ablation actuator to proximity to a target tissue, wherein the pulsed field ablation actuator includes an electrode having an ablation surface covered by a deformable insulator; (b) repositioning the pulsed field ablation actuator to make full contact with the target tissue, wherein full contact with the target tissue is operable to deform the deformable insulator and expose the previously covered ablation surface of the electrode; (c) supplying a current to the electrode while in full contact with the target tissue to induce electroperforation of the target tissue; and (d) repositioning the pulsed field ablation actuator to no longer make full contact with the target tissue, wherein inadequate contact with the target tissue is operable to deform the deformable insulator and cover the previously uncovered ablation surface of the electrode.

[0010] In a more detailed embodiment of the second aspect, the target tissue is cardiac tissue, and the contact is epicardial contact. In yet another more detailed embodiment, the target tissue is a nerve, and the contact is contact with at least one of an intact nerve and a dissected nerve. In a further detailed embodiment, the target tissue is an intercostal nerve, and the method is performed simultaneously with a thoracotomy. In yet another more detailed embodiment, the target tissue is cardiac tissue, and the contact is endocardial contact. In a more detailed embodiment, the pulsed field ablation actuator includes a first gripper and a second gripper, wherein electrodes include a first electrode portion on the first gripper and a second electrode portion on the second gripper, and repositioning the pulsed field ablation actuator to fully contact the target tissue includes: contacting the first electrode portion with the epicardial cardiac tissue and contacting the second electrode portion with the endocardial cardiac tissue, such that full contact with the epicardial and endocardial cardiac tissues is operable to deform the deformable insulator and expose the first and second electrode portions previously covered by the deformable insulator. In a more detailed embodiment, the method further includes performing cryoablation simultaneously with electroporation to destroy the target tissue or tissue in or near it. In another more detailed embodiment, the method further includes performing radiofrequency ablation simultaneously with electroporation to destroy the target tissue or tissue in or near it.

[0011] In another, more detailed embodiment of the second aspect, in the absence of sufficient contact between the target tissue and the deformable insulator, the deformable insulator is situated between the ablation surface of the electrode and the target tissue, and when sufficient contact occurs between the target tissue and the deformable insulator, the deformable insulator is no longer situated between the ablation surface of the electrode and the target tissue. In yet another, more detailed embodiment, when sufficient contact occurs between the target tissue and the deformable insulator, the tissue contact surface of the electrode protrudes from within the deformable insulator. In a further detailed embodiment, the electrode is segmented into a plurality of electrodes, each of which has a tissue contact surface, and the deformable insulator is segmented into a plurality of deformable insulator segments, wherein each of the plurality of electrodes is selectively covered by at least one of the plurality of deformable insulator segments, and when sufficient contact occurs between the target tissue and each of the plurality of deformable insulator segments, each of the plurality of deformable insulator segments is operable to expose the corresponding tissue contact surface of the plurality of electrodes. In a further detailed embodiment, the deformable insulator is segmented into a plurality of deformable insulator segments, wherein the ablation surface is selectively covered by at least one of the plurality of deformable insulator segments, wherein the deformable insulator is interposed between the ablation surface of the electrode and the target tissue in the absence of sufficient contact between the target tissue and each of the plurality of deformable insulator segments, and wherein each of the plurality of deformable insulator segments is operable to expose a portion of the ablation surface when sufficient contact is made between the target tissue and each of the plurality of deformable insulator segments.

[0012] A third aspect of the invention is to provide a method for suppressing unintended arc discharge across a pulsed field ablation electrode, the method comprising covering the pulsed field ablation electrode with a deformable insulator configured to change its shape between a first shape and a second shape in response to the application of a sufficient external force thereto, the first shape covering the tissue contact surface of the pulsed field ablation electrode and the second shape not covering the tissue contact surface of the pulsed field ablation electrode. Attached Figure Description

[0013] The description of the illustrative embodiments can be read in conjunction with the accompanying drawings. It should be understood that, for simplicity and clarity, the elements illustrated in the drawings are not necessarily drawn to scale. For example, the dimensions of some elements may be exaggerated relative to others. Embodiments incorporated into the teachings of this disclosure are shown and described with reference to the accompanying drawings presented herein.

[0014] Figure 1 This is a simplified schematic diagram of an example PFA system 100 based on at least some aspects of this disclosure.

[0015] Figure 2 This is a perspective view of an example clamp-type PFA device 200 according to at least some aspects of this disclosure.

[0016] Figure 3A This is a perspective view of an example minimally invasive PFA device 300 based on at least some aspects of this disclosure.

[0017] Figure 3B yes Figure 3A A simplified schematic diagram of the PFA device 300.

[0018] Figure 4A This is a perspective view of an example needle-type PFA device 400 according to at least some aspects of this disclosure.

[0019] Figure 4B yes Figure 4A A perspective view of an example needle-type PFA device 400.

[0020] Figure 4C yes Figure 4A An enlarged perspective view of the distal end of an example needle-type PFA device 400.

[0021] Figure 5A The figure shows an elongated, generally linear electrode according to at least some aspects of this disclosure.

[0022] Figure 5B The diagram illustrates point electrodes according to at least some aspects of this disclosure.

[0023] Figure 5C The diagram illustrates a segmented electrode according to at least some aspects of this disclosure.

[0024] Figure 5D The illustration shows an example of a nested electrode arrangement according to at least some aspects of this disclosure.

[0025] Figure 5E The illustration shows an example waveform electrode according to at least some aspects of this disclosure.

[0026] Figure 5F The illustration shows an example vertical electrode arrangement according to at least some aspects of this disclosure.

[0027] Figure 5G The illustration shows an example of a parallel electrode arrangement according to at least some aspects of this disclosure.

[0028] Figure 5H The illustration shows an example continuous electrode according to at least some aspects of this disclosure.

[0029] Figure 5I The illustration shows two example electrode arrays according to at least some aspects of this disclosure.

[0030] Figure 5J The illustration shows an example plate electrode according to at least some aspects of this disclosure.

[0031] Figure 5KThe illustration shows an example electrode configuration comprising multiple pairs of cooperating electrodes according to at least some aspects of this disclosure.

[0032] Figure 5L The illustration shows an example of a raised electrode according to at least some aspects of this disclosure.

[0033] Figure 5M The illustration shows an example electrode configuration including a protruding electrode positioned relative to a plate-shaped electrode, according to at least some aspects of this disclosure.

[0034] Figure 5N It is possible, for example, to combine with at least some aspects of this disclosure. Figure 2 , Figure 3A , Figure 4A and Figure 22 The simplified cross-sectional view shows an alternative example electrode configuration used in a PFA device that is substantially similar to the one shown.

[0035] Figure 5O It is possible, for example, to combine with at least some aspects of this disclosure. Figure 2 , Figure 3A , Figure 4A and Figure 22 The simplified cross-sectional view shows an alternative example electrode configuration used in a PFA device that is substantially similar to the one shown.

[0036] Figure 5P It is possible, for example, to combine with at least some aspects of this disclosure. Figure 2 , Figure 3A , Figure 4A and Figure 22 The simplified cross-sectional view shows an alternative example electrode configuration used in a PFA device that is substantially similar to the one shown.

[0037] Figure 5Q It is possible, for example, to combine with at least some aspects of this disclosure. Figure 2 , Figure 3A , Figure 4A and Figure 22 The simplified cross-sectional view shows an alternative example electrode configuration used in a PFA device that is substantially similar to the one shown.

[0038] Figure 5R It is possible, for example, to combine with at least some aspects of this disclosure. Figure 2 , Figure 3A , Figure 4A and Figure 22 The simplified cross-sectional view shows an alternative example electrode configuration used in a PFA device that is substantially similar to the one shown.

[0039] Figure 5S It is possible, for example, to combine with at least some aspects of this disclosure.Figure 2 , Figure 3A , Figure 4A and Figure 22 The simplified cross-sectional view shows an alternative example electrode configuration used in a PFA device that is substantially similar to the one shown.

[0040] Figure 5T It is possible, for example, to combine with at least some aspects of this disclosure. Figure 2 , Figure 3A , Figure 4A and Figure 22 The simplified cross-sectional view shows an alternative example electrode configuration used in a PFA device that is substantially similar to the one shown.

[0041] Figure 6A This is a simplified cross-sectional view of a vacuum fixture configuration according to at least some aspects of this disclosure.

[0042] Figure 6B The illustration shows an example embodiment of a baseline comprising generally flat opposing tissue bonding surfaces, according to at least some aspects of this disclosure.

[0043] Figure 6C The illustration shows an example embodiment of a mating surface of a relatively convex structure according to at least some aspects of this disclosure.

[0044] Figure 6D The illustration shows an example embodiment of a mating surface of a relatively concave structure, according to at least some aspects of this disclosure.

[0045] Figure 6E The illustration shows an example embodiment of a convex tissue engagement surface that is opposite to a cooperating concave tissue engagement surface, according to at least some aspects of this disclosure.

[0046] Figure 7 This is a graphical illustration of the composition of a multi-burst PFA signal according to at least some aspects of this disclosure.

[0047] Figure 8 This is a table listing example PFA signal parameters that can be used in conjunction with various PFA devices, based on at least some aspects of this disclosure.

[0048] Figure 9 It is a cross-sectional view according to at least some aspects of this disclosure, showing the placement of electrodes relative to each other and on opposite sides of the tissue, as part of the explanation of bipolar / monopolar configurations and biphase / monophase signals.

[0049] Figure 10A It is a diagram of example ECG traces based on at least some aspects of this disclosure.

[0050] Figure 10BThe illustrations show two example embodiments configured to mechanically measure the distance between relative grippers according to at least some aspects of this disclosure.

[0051] Figure 10C The illustrations show four example embodiments configured to measure the distance between relative grippers in an electrical and / or electronic manner, according to at least some aspects of this disclosure.

[0052] Figure 10D The illustration shows an example ratchet clamp mechanism according to at least some aspects of this disclosure.

[0053] Figure 11A This is a perspective view of an example insulator configuration according to at least some aspects of this disclosure, the insulator configuration comprising a compressible insulator that at least partially surrounds one or more electrodes.

[0054] Figure 11B yes Figure 11A Different perspective views of example insulator configurations are shown in the figure.

[0055] Figure 11C yes Figure 11A A simplified cross-sectional view of an embodiment.

[0056] Figure 12A This is a perspective view of an example insulator configuration that forms a shortened electrode exposure area according to at least some aspects of this disclosure.

[0057] Figure 12B yes Figure 12A A simplified cross-sectional view of an embodiment.

[0058] Figure 12C yes Figure 12A Another simplified cross-sectional view of an embodiment.

[0059] Figure 13A This is a perspective view of an example configuration including insulating grippers, based on at least some aspects of this disclosure.

[0060] Figure 13B yes Figure 13A A cross-sectional view of an embodiment.

[0061] Figure 13C This is a simplified perspective view of an alternative embodiment in which the electrodes are selectively insulated, according to at least some aspects of this disclosure.

[0062] Figure 14A This is a perspective view of an example configuration including grippers with selectively insulated electrodes, according to at least some aspects of this disclosure.

[0063] Figure 14B yes Figure 14A A cross-sectional view of an embodiment.

[0064] Figure 14C yes Figure 14A Another cross-sectional view of an embodiment.

[0065] Figure 15A This is a perspective view of an alternative example configuration including grippers with selectively insulated electrodes, according to at least some aspects of this disclosure.

[0066] Figure 15B yes Figure 15A A cross-sectional view of an embodiment.

[0067] Figure 15C yes Figure 15A Another cross-sectional view of an embodiment.

[0068] Figure 16A This is a perspective view of an alternative example configuration including grippers with selectively insulated electrodes, according to at least some aspects of this disclosure.

[0069] Figure 16B yes Figure 16A A cross-sectional view of an embodiment.

[0070] Figure 16C yes Figure 16A Another cross-sectional view of an embodiment.

[0071] Figure 17A This is a perspective view of an alternative example configuration including grippers with selectively insulated electrodes, according to at least some aspects of this disclosure.

[0072] Figure 17B yes Figure 17A A cross-sectional view of an embodiment.

[0073] Figure 17C yes Figure 17A Another cross-sectional view of an embodiment.

[0074] Figure 18A This is a perspective view of an alternative example configuration including grippers with selectively insulated electrodes, according to at least some aspects of this disclosure.

[0075] Figure 18B yes Figure 18A A cross-sectional view of an embodiment.

[0076] Figure 18C yes Figure 18A Another cross-sectional view of an embodiment.

[0077] Figure 18D The illustration shows an example embodiment of a deformable insulator disposed around electrodes arranged on a rigid backing plate, according to at least some aspects of this disclosure.

[0078] Figure 18E The illustration shows an example embodiment of at least some aspects of this disclosure, including spaced-out struts supporting electrodes within a deformable insulator.

[0079] Figure 18F The illustration shows an example embodiment of a raised feature comprising a deformable insulator according to at least some aspects of the present disclosure, which is configured to contact tissue and expose an electrode.

[0080] Figure 18G The illustration shows alternative example embodiments in which the deformable insulator can be segmented, according to at least some aspects of this disclosure.

[0081] Figure 19A This is a top view of an example lesion including a PFA zone and a thermal ablation zone, according to at least some aspects of this disclosure.

[0082] Figure 19B yes Figure 19A A cross-sectional view of the damage.

[0083] Figure 19C This is a top view of an example damage formed using a PFA and an RF device according to at least some aspects of this disclosure, illustrating the PFA zone and the thermal ablation zone.

[0084] Figure 19D The illustration shows an example snare fixture based on at least some aspects of this disclosure.

[0085] Figure 19E The illustration shows an example of a generally helical screw-engaged element for a gripper or electrode, configured to penetrate target tissue, according to at least some aspects of this disclosure.

[0086] Figure 20 This is a simplified side view of an example PFA device including an expandable structure, according to at least some aspects of this disclosure.

[0087] Figure 21 This is a simplified block diagram of an example apparatus configuration that can be used, for example, with various PFA and / or RF ablation devices and / or algorithms, based on at least some aspects of this disclosure.

[0088] Figure 22 This is a perspective view of an example minimally invasive PFA device based on at least some aspects of this disclosure.

[0089] Figure 23 It is a table listing exemplary parameters or settings for operating a PFA device, according to at least some aspects of this disclosure. Detailed Implementation

[0090] The following description and illustrations are based on exemplary embodiments of this disclosure to encompass devices, methods, and techniques related to PFA. It will be apparent to those skilled in the art that the embodiments discussed below are exemplary and can be reconfigured without departing from the scope and spirit of this disclosure. It should also be understood that variations of the exemplary embodiments conceived by those skilled in the art will also be included as part of this disclosure. However, for clarity and precision, the exemplary embodiments discussed below may include optional steps, methods, and features that those skilled in the art would recognize as not falling within the scope of this disclosure. Unless expressly stated otherwise, any feature or function described in connection with any exemplary embodiment may be applied to any other exemplary embodiment, and repeated descriptions of similar features and functions are omitted for brevity.

[0091] This disclosure contemplates that PFA can kill cells by inducing irreversible nanopore formation in the cell membrane using a high-intensity electric field (this is referred to as irreversible electroporation (“IRE”)). IRE can be used to create deep and uniform damage in cardiac tissue, which can be used to treat arrhythmias. If the intensity of the electrical signal applied to the target tissue is insufficient to induce IRE, reversible electroporation may occur. The pores formed by reversible electroporation may not be permanent, and the affected cells typically recover after a short time period (e.g., hours, days, weeks). This disclosure contemplates that the minimum electric field strength (or voltage) required to induce IRE may depend on the characteristics of the electrical signal applied to the target tissue and the target tissue itself. For example, the number of pulses, frequency, amplitude, duration, shape, etc., may affect the degree of electroporation. In some cases, the area of ​​IRE may be at least partially limited by the area of ​​reversible electroporation.

[0092] For the context of this study, an example PFA procedure configured to induce IRE may comprise a series of energy pulses (i.e., 100 volt direct current (VDC)) at a given duration (i.e., 100 microseconds (μs)) and a given frequency (i.e., 0.1 Hz to 10 Hz). For this type of procedure, an electric field is applied to the tissue to create a transmembrane voltage potential, which may range from 0.5 kV / cm to 2.5 kV / cm, depending on the tissue and the manner in which tissue damage is assessed. In some cases, electroporation efficacy may not be directly related to the amount of energy or charge delivered. For example, in some cases, with similar energy and charge, two 100 μs pulses of 1000 V / cm may be more effective at generating IRE than a single 200 μs pulse. Additional details and alternatives are described elsewhere in this document.

[0093] refer to Figure 1 , Figure 2 , Figure 3A ,Figure 3B and Figure 4A-4C The following description of the exemplary embodiments provides background to various exemplary apparatus features and methods that are described in more detail elsewhere herein. It should be understood that any embodiment of these exemplary embodiments may be used in conjunction with any features or aspects described elsewhere herein.

[0094] Turning Figure 1 Example PFA system 100 may include PFA unit 102, which may be operatively coupled to PFA device 104. PFA unit 102 may include PFA generator 106, which may be configured to generate and / or supply electrical pulses for PFA. PFA device 104 may be configured to apply PFA pulses to target tissue 10, thereby forming lesions 12 therein. In some example embodiments, PFA unit 102 may be provided as a basic (e.g., reusable) device, and / or PFA device 104 may be provided as a disposable (e.g., single-use) device.

[0095] In some example embodiments, the target tissue 10 may be located inside the patient's body 14. The PFA device 104 may be positioned to approach the target tissue 10 via any suitable patient access 16, such as an arterial or venous access, percutaneous access, open surgical access, and / or minimally invasive surgical access. For example, in relation to treating arrhythmias, the target tissue 10 may include the heart wall (e.g., myocardium). In some example embodiments, the PFA device 104 may be positioned substantially against the outer (e.g., epicardium) surface of the heart wall and / or substantially against the inner (e.g., endocardium) surface of the heart wall.

[0096] In some example embodiments, the PFA unit 102 may include various other components and / or may be used in combination with various other components. For example, in some example embodiments, a foot switch 108 may be used to activate certain functions associated with the PFA unit 102, such as delivering ablation energy to the PFA device 104. In some example embodiments, the return electrode 110 may be electrically coupled to the patient's body 14, such as to provide a return path for the monopolar ablation energy delivered via the PFA device 104.

[0097] In some example embodiments, one or more ECG electrodes 114 may be used, and an electrocardiogram (“ECG”) monitor 112 may be used to display and / or analyze electrical pulses associated with the patient’s heartbeat. In some example embodiments, the ECG monitor 112 may be operatively coupled to and / or incorporated into the PFA unit 102, such as to facilitate synchronization of ablation pulse timing with the patient’s heartbeat, as described below.

[0098] In some example embodiments, PFA unit 102 may be configured to provide PFA energy only. In some example embodiments, PFA unit 102 may be configured for use in conjunction with additional ablation modalities. For example, PFA unit 102 may include one or more components configured for RF ablation and / or may be used in conjunction with such components, such as RF generator 116, which may be substantially similar to the Ablation Sensing Unit (ASU), Ablation Switch Box (ASB), and / or Estech Electrosurgical Unit (ESU) available from AtriCure Ltd., Mason, Ohio. As another example, PFA unit 102 may include one or more components configured for cryosurgery ablation and / or may be used in conjunction with such components, such as cryosurgery unit 118, which may be substantially similar to the cryoICE BOX cryosurgery unit available from AtriCure Ltd., Mason, Ohio. Generally, a specific lesion (or a portion thereof) can be formed using PFA, one or more other forms of ablation, or any combination thereof, in any order and / or simultaneously (e.g., PFA and / or RF and / or cryotherapy).

[0099] In some example embodiments, the PFA unit 102 may include one or more indicators and / or displays 120 that can provide the operator with information about the patient, the PFA unit 102, and / or the ablation. For example, some PFA units 102 may include integrated tissue inquiry / mapping functions (such as voltage mapping, impedance mapping, exit / entry block testing of lesions via cardiac pacing and sensing), which can use one or more dedicated electrodes and / or one or more electrodes associated with the PFA device 104. In some example embodiments, the PFA unit 102 may include one or more input devices 122, such as knobs, dials, switches, buttons, touchscreens, etc., that can allow the operator to guide the operation of various components of the PFA unit 102.

[0100] In some example embodiments, PFA unit 102 may be configured to have one or more external connections. For example, PFA unit 102 may be operatively connected to electrical power supply 124, such as a wall socket. Some example embodiments may be operatively connected to vacuum source 126, such as an operating room vacuum system. Some example embodiments may be operatively connected to gas source 128, such as a compressed gas cylinder, which may, for example, contain cryogenic fluids.

[0101] In some example embodiments, the PFA device 104 may include one or more electrodes 130, which may be disposed in or on the end effector 132 to deliver PFA energy to the target tissue 10.

[0102] The description herein refers to distal direction 18 and proximal direction 20. Proximal direction 20 may generally be opposite to distal direction 18. As used herein, “distal” can refer to a direction generally away from the operator of the system or device (e.g., a surgeon), such as toward the distal end of the device inserted into the patient’s body. As used herein, “proximal” can refer to a direction generally toward the operator of the system or device (e.g., a surgeon), such as away from the distal end of the device inserted into the patient’s body. However, it should be understood that the illustrative directions referred to herein are for purposes of explanation and clarity only and should not be considered limiting.

[0103] refer to Figure 1 and Figure 2 The illustrated clamp-type PFA device 200 may include a handle 202 disposed proximally, a shaft 204 extending distally from the handle 202, and / or an end effector 206 disposed distally on the shaft 204. Generally, some example PFA devices 200 may be similar to the "IsolatorSynergy" surgical ablation device available from AtriCure, Inc., Mason, Ohio, and / or the device described in U.S. Patent No. 9,072,518 entitled "HIGH-VOLTAGE PULSEABLATION SYSTEMS AND METHODS," published July 7, 2015, which is incorporated herein by reference in its entirety. Furthermore, various PFA devices having any configuration and according to at least some aspects of this disclosure can employ overlapping fields (e.g., focused between paired electrodes), on / off duty cycles (e.g. for thermal management), and / or switching to constant signal generation of multiple electrode pairs, generally similar to those utilized by the "Isolator Synergy" device and / or as described in U.S. Patent No. 9,072,518.

[0104] In general, any handle described herein with reference to any exemplary embodiment can be configured to be grasped by a human user (e.g., a surgeon) and / or engaged by a non-human, mechanical, and / or robotic device (e.g., a surgical robot). More generally, any handle described herein can include any structure in which the mechanism can be configured to be secured, held, and / or manipulated to position and / or restrain a PFA device, regardless of whether it can be grasped by a human (e.g., a surgeon or assistant), robot, mechanical device, etc.

[0105] In the illustrated embodiment, a proximal connecting element 208 can electrically connect the PFA device 200 to the PFA unit 102. In some embodiments utilizing vacuum and / or cryogenics, the connecting element 208 may include suitable conduit. The end effector 206 corresponding to the end effector 132 may include a distally repositionable or fixed gripper 210 and / or a movable proximal gripper 212. A plunger 214 or other actuator that may be positioned proximal on the handle 202 may allow the operator to reposition one or both grippers 210, 212 to clamp the target tissue 10 between the grippers 210, 212. In the illustrated embodiment, one or both of the grippers 210, 212 may include one or more electrodes 216 corresponding to the electrode 130, which can be used to deliver PFA energy to the target tissue 10. In embodiments including one or more electrodes, the electrodes may be positioned on any one or both grippers 210, 212.

[0106] refer to Figure 1 , Figure 3A and Figure 3B The illustrated minimally invasive PFA device 300 may include a proximal handle 302, a flexible connecting element 304 extending distally from the handle 302, and / or an end effector 306 distally disposed on the connecting element 304. Generally, some example PFA devices 300 may be similar to the “COBRA Fusion” ablation system available from AtriCure, Inc., Mason, Ohio, and / or the device described in U.S. Patent No. 9,474,574, entitled “STABILIZEDABLATION SYSTEMS AND METHODS,” published October 25, 2016, which is incorporated herein by reference in its entirety.

[0107] In the illustrated embodiment, a proximal electrical connection element 308 can electrically connect the PFA device 300 to the PFA unit 102. A proximal vacuum connection element 310 can fluidly connect the PFA device 300 to the PFA unit 102 and / or the vacuum source 126. In the illustrated embodiment, the end effector 306 corresponding to the end effector 132 may include an elongated flexible stabilizer 312 configured to releasably engage the target tissue 10, such as by using a vacuum. In the illustrated embodiment, one or more electrodes 314A, 314B corresponding to the electrodes 130 may be disposed within the stabilizer 312 and / or may be used to deliver PFA energy to the target tissue 10. In some example embodiments, the PFA device 300 may be configured for vacuum-stabilized, unidirectional and / or bipolar (or selectively bipolar / unipolar) operation. In some example embodiments, the target tissue may be folded, such as approximately within... Figure 3BAs shown in the diagram. In some embodiments, the target tissue can be drawn into contact with electrodes 314A and 314B without substantial tissue folding. It can be utilized in a similar manner. Figure 22 The PFA device 2200 is shown in the figure.

[0108] refer to Figure 1 as well as Figure 4A-4C The illustrated needle-type PFA device 400 may include an elongated flexible connecting element 402 and / or an end effector 404 disposed distally on the connecting element 402. The connecting element 402 can electrically connect the PFA device 400 to the PFA unit 102. In the illustrated embodiment, the end effector 404 corresponding to end effector 132 may include a generally rigid housing 406 and / or one or more electrodes in the form of outwardly extending needles or pins 408, 410, configured to engage the target tissue 10, such as by forming a recess in or penetrating the target tissue 10. In some example embodiments, such penetration may provide desired tissue contact. The electrodes 408, 410 corresponding to electrode 130 may be used to deliver PFA energy to the target tissue 10. In the illustrated embodiment, the electrodes are spaced apart by a fixed electrode spacing 412. In some example embodiments, at least a portion of at least one pin 408, 410 (such as the proximal portion of one or more pins 408, 410) may be covered by insulators 414, 416. In various example embodiments, one or more pins 408, 410 may be generally blunt-tipped and / or generally pointed. Example pin profiles may include short (shallow depth) pins and / or long (deep depth) pins, and combinations thereof. In some example embodiments, one or more pins 408, 410 may be in the form of hollow needles configured to inject material into target tissue. In some such embodiments, material may be injected into target tissue, and PFA energy may then be delivered to the target tissue via the needles acting as electrodes.

[0109] Given by Figure 1 , Figure 2 , Figure 3A , Figure 3B as well as Figure 4A-4C The following description provides context for the example embodiments and various optional and alternative aspects and features.

[0110] Generally, PFA devices can be configured for unidirectional and / or bidirectional operation. As used herein, "unidirectional" can generally refer to applying PFA energy to the tissue from one side. For example, applying PFA energy only to the epicardial surface of the heart, without applying PFA energy to the opposite endocardial surface, is an example of unidirectional operation. As used herein, "bidirectional" can refer to applying PFA energy to the tissue from two opposite sides, such that PFA energy flows through the tissue.

[0111] Examples of unidirectional devices may include needle-type PFA devices, pen-type PFA devices configured to form point-like and / or linear lesions, endocardial catheter PFA devices, some minimally invasive epicardial PFA devices, and / or surface-based end effectors comprising multiple electrodes operating at predetermined different voltages. Some clamp-type devices (such as those using electrodes on only one gripper) may have a unidirectional configuration.

[0112] Example bidirectional devices may include clamp-type PFA devices, grippers, some minimally invasive epicardial PFA devices, and / or systems configured (e.g., using magnetic coupling) to place cooperating electrodes on opposite sides of tissue (such as the endocardial and epicardial surfaces of the heart) or on the anterior and posterior surfaces of body conduits. Example clamp-type PFA devices may be configured as clamping or non-clamping devices, and / or may be configured to generally surround anatomical structures (e.g., pulmonary veins), or configured to ablate the walls of hollow organs by inserting a gripper into a surgical purse-string suture.

[0113] Some PFA devices (such as reference) Figure 1 , Figure 2 , Figure 3A , Figure 3B as well as Figure 4A-4C The electrode configurations described herein may include a variety of electrode configurations. In general, any combination or variation of the electrode configurations described herein may be used in conjunction with any embodiment according to at least some aspects of this disclosure.

[0114] refer to Figure 5A-5T , Figure 5A The illustration shows a long, typically linear (e.g., “filamentous”) electrode that may be generally straight or may include one or more curves and / or angles, and may be repeated to provide multiple electrodes as desired. Figure 5B The illustrated point (e.g., “point-like”) electrode may be generally circular or may have other shapes, such as a sheath electrode with an exposed point. Figure 5C The diagram illustrates a segmented electrode comprising multiple discrete, generally rectangular segments, although segments with other similar or different shapes may be used. In some example embodiments, these segments may be electrically connected to each other. These discrete portions may be arranged as lines, curves, meandering paths, stacks, or other arrangements. Figure 5D The illustration illustrates a nested electrode arrangement, in which one or more electrodes are sequentially positioned inside another electrode. In the illustrated embodiment, one or more generally annular and / or circular electrodes or electrode segments may be arranged generally concentrically inside each other. However, other closed shapes may be used, such as, but not limited to, triangles, rectangles, pentagons, hexagons, octagons, etc.

[0115] Figure 5E The illustrated example waveform electrode includes one or a series of elongated electrodes having multiple curves in opposite directions that may resemble sine curves. Figure 5F The illustrated example shows a vertical electrode arrangement that includes a first segment that is generally orthogonal to the second segment. These segments may be connected as a single electrode, or they may be unconnected as two separate electrodes or segmented electrodes. In the illustrated embodiment, each segment includes a generally straight electrode. Figure 5G The illustrated example shows a parallel electrode arrangement, which includes a first segment positioned generally parallel to a second segment. In the illustrated embodiment, each segment includes a generally straight electrode. Furthermore, depending on the application, more than two parallel electrodes may be used.

[0116] Figure 5H The illustration shows a continuous electrode, while Figure 5I The illustration shows two example electrode arrays. Generally, continuous electrodes can have a continuous surface presented to the tissue, regardless of the electrode's shape. Generally, discontinuous electrode arrays can include two or more segments with separate tissue contact surfaces. Each segment can have any shape, such as generally circular and / or generally straight. In some example embodiments, the two or more segments of the electrode array can be electrically connected. In some example embodiments, the two or more segments of the electrode array can be electrically isolated from each other, such that, for example, each delivers different or the same electrical signal to the tissue.

[0117] Figure 5J The illustrated example is a plate-shaped electrode, which may include a two-dimensional or three-dimensional electrode surface having a considerable width in terms of its length, regardless of its shape. The plate-shaped electrode may be provided, for example, in a continuous or segmented configuration. Figure 5K The illustration shows an example electrode configuration with multiple pairs of cooperating electrodes. Figure 5L The illustration shows a raised electrode. Generally, a raised electrode can protrude from the surrounding surface of a PFA device. In some embodiments, one or more electrodes can be configured to be flush with the surrounding surface. That is, the tissue contact surface of the electrode can be substantially coplanar with the surrounding surface. In some embodiments, one or more electrodes can be recessed into the surrounding surface. That is, the tissue contact surface of the electrode can be embedded relative to the surrounding surface. Figure 5M The illustration shows an example electrode configuration with a raised electrode positioned relative to a plate-shaped electrode.

[0118] Figure 5N-5T This is a simplified cross-sectional view of an alternative example electrode configuration that can be used, for example, in conjunction with PFA devices substantially similar to PFA devices 200, 300, 400, and 2200, according to at least some aspects of this disclosure. However, it should be understood that similar configurations can also be used in other PFA devices. Specifically, Figure 5NA longitudinal cross-sectional view is illustrated of an example elongated (e.g., filamentous) electrode configuration including two electrodes 502, 504. In this embodiment, the elongated electrodes 502, 504 may be arranged as opposing pairs, such as for bipolar operation. The electrodes 502, 504 may be generally longitudinally oriented and / or may be at least partially recessed within the stabilizer 312. Figure 5O A longitudinal cross-sectional view is illustrated of an example multi-elongated (e.g., filamentous) electrode configuration including four electrodes 506, 508, 510, and 512. In this embodiment, the elongated electrodes 506, 508, 510, and 512 may be arranged in two opposing pairs and / or may be generally longitudinally oriented. However, more than two pairs of electrodes are also within the scope of this disclosure. Figure 5P A side cross-sectional view of the continuous electrode configuration 514 and the segmented electrode configuration 516 is illustrated. In the illustrated embodiment, the individual electrodes 516A, 516B, 516C of the segmented electrode configuration 516 may be electrically connected as a group or driven individually, but may individually contact the target tissue.

[0119] Figure 5Q A side view illustrating an example electrode arrangement including opposing tissue-penetrating needle electrodes is shown. In the illustrated embodiment, a first gripper 517 includes at least one needle electrode 518 extending therefrom. A second opposing gripper 519 includes at least one needle electrode 520 extending therefrom. In the illustrated embodiment, the needle electrodes 518, 520 are arranged in a respective array. The spacing between the needles 518, 520 can be fixed at a known predetermined distance. Although the illustrated embodiment includes examples that may represent clamp-type PFA devices (e.g., Figure 2 The grippers 210 and 212 of the PFA device 200 shown in the figure have grippers 517 and 519, but it should be understood that this relative needle arrangement can be used with other configurations of PFA devices such as PFA devices 300 and 400.

[0120] Figure 5R Draw Figure 22 The diagram shows a partial cross-sectional perspective view of the minimally invasive PFA device 2200, where the electrodes can typically be in the form of spiral electrodes 2202. Figure 5S A simplified distal perspective view of an example electrode configuration including multiple arched filamentary electrodes 522 is shown. In this embodiment, the arched filamentary electrodes 522 may be at least partially disposed in the stabilizer ( Figure 3A Within, and can be oriented substantially parallel laterally, and / or configured to engage target tissue on the corresponding concave surface. Figure 5T A simplified distal perspective view of an example electrode configuration including multiple arched plate electrodes 524 is shown. In this embodiment, the arched plate electrodes 524 may be at least partially disposed in the stabilizer ( Figure 3AWithin, and can be oriented substantially parallel to the side, and / or configured to engage the target tissue on the corresponding concave surface. Generally speaking, Figure 5T The arched plate electrode 524 can be similar to Figure 5S The arched filament electrode 522; however, in some embodiments, the arched plate electrode 524 may be wider than the arched filament electrode 522 (e.g., in the longitudinal direction).

[0121] In some example embodiments, a clamp-type PFA device (e.g., similar to PFA device 200) may include various features. Generally, a clamp-type device can be configured for dynamic closure and / or static closure.

[0122] Example embodiments configured for dynamic closure may utilize static and / or dynamic grippers. For example, static grippers (e.g., grippers that do not change orientation during use) can be dynamically configured using a spring-loaded closure mechanism. In some such embodiments, the closure force is provided primarily by the spring force, and gripper separation in the closure configuration depends on tissue thickness and compressibility. In other embodiments, static grippers can be dynamically configured using a user-applied closure force. Therefore, gripper separation and closure force in the closure configuration are directly controlled by the user. Example embodiments including dynamic grippers may include compressible gripper surfaces, conformal grippers (e.g., grippers that deform under designed closure forces), and / or flexible grippers.

[0123] Some example embodiments configured for static closure can utilize pressure setting. That is, a closure force up to a preset desired level can be applied. In this case, further applied closure force will be ineffective for further closing of the grippers.

[0124] refer to Figure 6A Some example embodiments configured for static closure may utilize a fixed distance setting. That is, the grippers are closed to a predetermined gripper spacing, regardless of the closure force required to achieve this spacing. In some example embodiments employing a fixed distance setting, the PFA device may utilize both clamping and vacuum tissue engagement features. For example, Figure 6A A simplified cross-sectional view of a vacuum clamp configuration according to at least some aspects of this disclosure is illustrated. In the illustrated embodiment, the grippers are positioned around target tissue and moved into a closed configuration. A vacuum is applied to the grippers to maintain or increase contact with the desired tissue.

[0125] Some example embodiments can be configured for mixed set-distance / dynamic closure operations. For example, an initial closure of the clamp can be performed to a set distance. This can facilitate PFA, such as at a fixed or known V / cm. The clamp can then be dynamically closed, such as to prepare for RF ablation. Some example embodiments may include a closure mechanism that provides this sequence of operations, or can switch between such operating modes (e.g., user-selectable). In some example embodiments, the closure mechanism operating mode (e.g., dynamic versus fixed distance) can be determined by combining the output of the selected electrosurgical generator (e.g., PFA versus RF ablation). In alternative embodiments, dynamic closure can be performed first, followed by set-distance closure, such as performing RF ablation followed by PFA.

[0126] Some example embodiments may utilize variable distance settings. That is, the grippers can be closed to a specific distance, such as a distance that can be determined by the user and / or indicated by a stop or visible scale, but this distance may vary due to ablation.

[0127] refer to Figure 6B-6E Some example embodiments may utilize opposing grippers that include cooperative tissue engagement features. For example, the insulating portion of the gripper near the electrode may be configured to have various shapes in order to engage target tissue. Figure 6B The illustration includes a baseline example embodiment of a generally flattened, opposing tissue bonding surface; Figure 6C The illustration includes an example embodiment of a mating surface with opposing convex structures; Figure 6D The illustration includes an example embodiment of a mating surface with opposing concave tissue surfaces; Figure 6E The illustrations include example embodiments of convex tissue engagement surfaces opposite to the cooperating concave tissue engagement surfaces; all of these example embodiments are based on at least some aspects of this disclosure.

[0128] In some example embodiments, the tissue-bonding surface (e.g., an insulator) may be substantially rigid. That is, the insulator does not deform significantly under design loads. In some example embodiments, the tissue-bonding surface (e.g., an insulator) may be substantially compliant. That is, the insulator may be configured to deform under design loads, such as to conform to the target tissue. In some example embodiments, the tissue-bonding surface may be partially rigid and / or partially compliant, thereby adaptable to achieve the desired tissue contact.

[0129] Turning Figure 7 The following are graphical illustrations illustrating the composition of example multi-burst PFA signals, based on at least some aspects of this disclosure. Figure 8 A table illustrating example PFA signal parameters that can be combined with various PFA devices, based on at least some aspects of this disclosure. Figure 8In this context, "fusion" refers to a device similar to the PFA device 300 shown in Figure 3, and "needle" refers to a device similar to... Figure 4A-4C The device of PFA device 400 shown, "fixture" refers to a device similar to Figure 2 The device of PFA device 200 shown, "epi endocardium" refers to a PFA system including an epicardial PFA device that operates in cooperation with a PFA device located in the endocardium, and "evenflow" refers to a PFA device including multiple electrodes operating at predetermined different voltages. The parameters listed are merely examples and should not be considered limiting in any way.

[0130] In various example embodiments, the PFA signal may include single-phase pulses and / or biphase pulses. Individual pulses may include square waves, and / or the voltage may vary over time. For example, individual pulses may include generally sinusoidal waveforms. Individual pulses may be delivered in bursts (e.g., pulse trains). A series of multiple bursts may be delivered. Some example embodiments may deliver pulses at specific, predetermined times relative to the patient's heartbeat.

[0131] The pulse characteristics can be modified and selected to achieve the desired result. For example, the alternating current (“AC”) or direct current (“DC”) waveform, pulse amplitude, number of pulses in the pulse train, number of bursts, pulse repetition frequency, burst repetition frequency, pulse width (e.g., nanoseconds or greater), and so on, can be changed. In some example embodiments, some or all of these characteristics may remain substantially constant. In some example embodiments, one or more characteristics may vary, for example, during the ablation process. For instance, some characteristics may be programmed to vary over time.

[0132] In some example embodiments, the operation of the PFA system can be configured to measure one or more parameters associated with the ablation operation in real time or with a time delay, and / or utilize data related to such parameters to control the delivery of PFA energy. In some example embodiments, aspects of PFA energy delivery can be implemented and / or suppressed, at least in part based on the detection and / or measurement of some parameters. In some example embodiments, one or more aspects of PFA energy delivery can be adjusted and / or controlled, at least in part based on the detection and / or measurement of one or more parameters.

[0133] In some example embodiments, the contact force between the end effector and the target tissue, or a parameter associated with the contact force, can be measured. For example, in embodiments employing vacuum stabilization, the vacuum level can be measured. In embodiments employing magnetic attraction, the magnetic attraction force can be measured.

[0134] In some example embodiments where the spacing between the electrodes can vary, this spacing can be measured as described elsewhere herein.

[0135] In some example embodiments, one or more temperatures can be measured. For example, one or more end effector temperatures, electrode temperatures, and / or tissue temperatures can be measured.

[0136] In some example embodiments, tissue conductance can be measured. For example, tissue conductance can be measured using the same electrodes that can be used to deliver PFA energy. Alternatively, additional electrodes, different from those used to deliver PFA energy, can be used to measure tissue conductance. Tissue conductance measurements can be evaluated as absolute conductance values ​​and / or based on changes in conductance, such as percentage changes in conductance due to ablation. In some cases, tissue conductance may increase due to PFA, thus such measurements can facilitate the assessment of ablation effectiveness and / or progress.

[0137] In some example embodiments, the current delivered in conjunction with the PFA can be measured.

[0138] In some example embodiments, ablation time can be measured.

[0139] This disclosure considers tissue selectivity as a relevant factor when ablating tissue, which can refer to the ability to selectively destroy specific tissue while minimizing damage to other non-target, nearby tissues. For example, ablation of myocardial tissue can occur near the phrenic nerve, esophagus, and coronary arteries.

[0140] This disclosure considers that the tissue selectivity of PFAs can be influenced by various factors, including the duration and intensity of the electric field, the shape and size of the electrodes, and the electrical properties of the target tissue. Generally, PFAs can be more selective for tissues with higher conductivity (such as myocardium) and less selective for tissues with lower conductivity (such as adipose or fibrous tissue). In some cases, PFA energy delivered via electrical signals with certain characteristics may significantly damage myocardium and / or may slightly damage nerve tissue and / or blood vessels.

[0141] This disclosure considers that, in general, the electric field strength (E) (also referred to as the applied electric field) is directly proportional to the applied voltage (V) and inversely proportional to the electrode spacing (d), as given by the following equation: Electrode spacing (d) is defined as the distance between electrodes used to deliver high-voltage electrical pulses to target tissue. In some example embodiments, the IRE can be generated by an electric field strength of approximately 2,500 V / cm to 10,000 V / cm.

[0142] This disclosure considers that electrode spacing may affect the spatial distribution of the electric field within tissue. Specifically, as electrode spacing increases, the electric field may become less concentrated because it is distributed over a larger area; while at smaller electrode spacing, the electric field may become more concentrated because it is concentrated in a specific region of the tissue.

[0143] This disclosure considers that electrode exposure can also affect the spatial distribution of the electric field within the tissue. Electrode exposure refers to the amount of electrode surface area in direct contact with the tissue being treated. Generally, greater electrode exposure may result in a more uniform electric field distribution across the tissue, which could lead to more effective destruction of the target tissue. In contrast, less electrode exposure may result in a more localized electric field distribution within a smaller tissue area. Electrode exposure can be controlled by adjusting the size and shape of the electrodes and / or by changing the distance between the electrodes and the tissue. In some cases, multiple electrodes (more than two) can be used to achieve greater electrode exposure and / or a more uniform electric field distribution.

[0144] This disclosure considers that pulse width may play an important role in determining the effectiveness of PFA treatment. Pulse width can be the duration of an electric field applied to tissue. Generally, a longer pulse width may correspond to an increased likelihood of induced IRE. However, in some cases, a pulse width that is too short may not deliver sufficient energy to the tissue to produce the desired effect.

[0145] This disclosure considers that residence time can determine the amount of energy delivered to the tissue during PFA and thus may affect the extent of tissue damage. Residence time can refer to the time between individual pulses and / or the time between pulse clusters or groups.

[0146] This disclosure considers that pulse repetition frequency may affect the duration and / or frequency of tissue exposure to an electric field, which in some cases may affect efficacy, selectivity, and / or safety. Generally, pulse repetition frequency refers to the frequency at which electrical pulses are delivered during PFA. In some cases, increasing the pulse repetition frequency may increase selectivity and reduce the likelihood or amplitude of undesirable muscle stimulation.

[0147] This disclosure considers that the number of pulses delivered to tissue may affect the extent of tissue damage and / or the effectiveness of treatment. The number of pulses can refer to the total number of discrete instances of applying a high-voltage current to the target tissue during a specific treatment. Generally, reducing the number of pulses for a given high-voltage current can reduce the likelihood of undesirable heating of the tissue.

[0148] refer to Figure 9 The following description explains the bipolar / single-polar configuration and biphase / single-phase signal according to at least some aspects of this disclosure.

[0149] The terms "bipolar" and "monopolar" can refer to the electrical configuration of electrodes used to deliver high-voltage electrical pulses to the tissue being treated. Generally, in a monopolar configuration, a single active electrode (or group of electrodes) is used to deliver electrical pulses to the tissue, while another electrode and / or grounding pad is typically placed elsewhere on the patient's body to complete the circuit. This configuration can result in a less controlled electric field distribution and / or potentially damage healthy tissue near the treatment area. In a bipolar configuration, two active electrodes (or groups of electrodes) can be placed near the tissue being treated, with a high-voltage electrical pulse delivered between the two electrodes. This configuration can result in a more localized electric field distribution, which can reduce the risk of damage to healthy tissue outside the treatment area. While both bipolar and monopolar configurations are used in PFA, in some cases, a bipolar configuration may offer potential safety and / or effectiveness advantages. For example, in some cases, a bipolar configuration may provide improved electric field control and / or more controlled damage formation, and / or may result in less skeletal muscle stimulation.

[0150] The terms "biphasic" and "monophasic" can refer to the waveform of the electrical pulses used in PFA treatment. A monophasic pulse may consist of a single high-voltage electric field applied to the tissue for a short duration. This pulse can be considered a unidirectional wave propagating through the tissue. A biphasic pulse may consist of two consecutive pulses of opposite polarity. The polarity of the electric field reverses between the two pulses, resulting in a bidirectional waveform that oscillates back and forth in the tissue. In some cases, biphasic pulses may be more effective at disrupting cell membranes in some tissues compared to monophasic pulses.

[0151] This disclosure considers that, in some cases, the delivery of electrical energy to body tissues may lead to muscle contraction. In some cases, muscle tissue may contract due to direct stimulation by electrical energy. In some cases, muscle tissue may contract due to stimulation of nerve tissue by electrical energy. In the context of electrical ablation of cardiac tissue, electrical energy may lead to stimulation of the cardiac muscle and / or of non-cardiac skeletal muscles. For example, such stimulation may include involuntary contractions and / or twitching.

[0152] In some example embodiments, the delivery of PFA energy to cardiac tissue can be timed to coordinate with the patient's heartbeat. For example, the delivery of PFA energy can be timed to be aligned with and / or not aligned with a specific part of the cardiac cycle. For example, electrical energy can be applied when the heart is in its refractory period, which can reduce the likelihood of muscle spasms. For example, as illustrated in Figure 10, a diagram of an example ECG trace according to at least some aspects of this disclosure is disclosed. In some embodiments, the delivery of PFA energy can be initiated on the downslope of the R wave, which may reduce the likelihood of undesirable cardiac stimulation and / or arrhythmias. Specifically, on the downslope of the R wave, cells have been depolarized and therefore are generally unable to respond to PFA signals. In some cases, by applying the first pulse of a series of pulses on the downslope of the R wave, subsequent pulses can be applied at different frequencies without causing adverse effects. In particular, regardless of the frequency of subsequent pulses, the heart can be stimulated to beat at a maximum rate of about five beats per second and is likely to return to a normal sinus rhythm after ablation.

[0153] In some example embodiments that employ pacing signals to drive the heart at a known rate, PFA energy delivery can be timed in coordination with the pacing signals.

[0154] In some example embodiments, PFA energy delivery parameters can be selected to reduce the likelihood of undesirable cardiac and / or skeletal muscle stimulation. For example, delivering electrical energy at a frequency of approximately 100 kHz or higher may result in less muscle stimulation.

[0155] This disclosure addresses the possibility that, at certain voltages used in PFA (Potentially Assisted Aesthetic Components), arcing may occur between the electrodes, leading to unintended tissue burns, cardiac arrest, hearing loss, blindness, neurological damage, and / or death, depending on the placement of the PFA electrodes. In other PFA scenarios, arcing may occur between the electrodes of the PFA device and the patient's tissues (e.g., target or non-target tissues). Therefore, mitigating unintended arcing may be a consideration in the design and operation of PFA systems.

[0156] In some example embodiments, arcing can be reduced by ensuring sufficient contact force or pressure between the PFA electrode and the target tissue. For example, some embodiments may utilize vacuum stabilization to increase contact pressure. The vacuum chamber may include a fluid flow containing a conductive fluid to ensure tissue-electrode contact. Some embodiments may utilize a clamp-type configuration to increase contact pressure. Some embodiments may utilize an expandable structure to increase contact pressure.

[0157] In some example embodiments, arc discharge can be reduced by covering, rinsing, and / or immersing the electrodes and / or tissue in a dielectric fluid such as deionized water.

[0158] In some example embodiments that include multiple electrodes, one or more electrodes may be selectively activated and / or deactivated. For example, one or more electrodes in contact with the target tissue may be activated, and / or one or more electrodes not in contact with the target tissue may be deactivated / deactivated in combination with the specific application of PFA energy. For example, one or more electrodes not in contact with any tissue and / or one or more electrodes in contact with tissues other than the target tissue may be deactivated. Electrodes may be manually deactivated by the user, automatically deactivated by performing an electrical contact test using the applied voltage to confirm tissue contact, or deactivated by a combination thereof. In some example embodiments, some electrodes may be selectively used for specific ablation modalities (e.g., PFA, RF).

[0159] In some example embodiments, including PFA devices comprising two or more electrodes, the PFA device can be configured such that the spacing between adjacent electrodes is sufficient to prevent arcing at the desired voltage. For example, given the maximum voltage difference between two adjacent electrodes, a minimum spacing to prevent arcing can be determined. In some embodiments, this spacing can be fixed when the device is constructed by rigidly setting the electrodes at the desired spacing. In some embodiments, such as clamp-type devices with electrodes positioned on opposing jaws, mechanical controls can be incorporated to limit the closing movement of the jaws to a minimum separation distance, thereby providing sufficient electrode spacing to prevent arcing; and / or electrical controls can be incorporated to suppress electrode operation when the electrode spacing is insufficient. Such controls can be located in an end effector acting on or near one or more jaws; and / or in a handle acting on or near a user-operated actuation element; and / or in the PFA unit 102 as a physical circuit system and / or programming code.

[0160] In some example embodiments, potential arcing conditions can be detected and / or prevented. For example, a PFA device and / or PFA unit can be configured to prevent the delivery of PFA energy when a potential arcing condition is detected. Alternatively, the PFA device and / or PFA unit can be configured to adjust its operation based on the detection of a potential arcing condition. For example, electrodes that do not contact tissue can be deactivated, thus allowing PFA energy to be applied only through electrodes that are in substantial contact with tissue. In some example embodiments, parameters associated with an arcing condition can be detected, and energy delivery can be terminated. For example, if voltage, current, conductivity, impedance, or other electrical parameters associated with arc ignition are detected, example PFA unit 102 can terminate energy delivery to the PFA device.

[0161] Some example embodiments that allow for variable electrode spacing (e.g., at least one electrode can be repositioned relative to at least one other electrode) can be configured to measure the electrode spacing, such as before PFA energy is delivered to the electrodes. In some clamp-type embodiments, determining the gripper separation distance may be related to the electrode spacing. For example, if the electrode spacing is determined to be insufficient to prevent arcing at the desired voltage, the PFA system can prevent the delivery of PFA energy to the electrodes. In some example embodiments, the maximum voltage delivered to the electrodes can be adjusted at least in part based on the detected or determined electrode spacing. That is, for example, the maximum voltage may be lower when a closer electrode spacing is detected or determined; and / or the maximum voltage may be higher when a farther electrode spacing is detected or determined.

[0162] In some clamp-type PFA devices, jaw separation can be controlled and / or determined mechanically and / or electrically. Example mechanical configurations may include, for example, mechanisms configured to measure the distance between relative jaws, ratchet mechanisms associated with the distance between jaws, window cutouts on shafts or handles indicating jaw separation, and / or scale markings on shafts. Example electrical configurations may include magnets and Hall effect sensor devices, linear potentiometers, lasers, echo sensors, infrared sensors, and / or tissue impedance devices.

[0163] Turning Figure 10B The illustrations show two example embodiments configured to mechanically measure the distance between relative grippers. As illustrated, in some embodiments, scale markings may be provided, for example, on a component stationary relative to the moving drive lever, or may be provided on the moving drive lever itself.

[0164] refer to Figure 10C The illustrations show four example embodiments configured to measure the distance between relative grippers electrically and / or electronically. As illustrated, some embodiments may include, for example, a linear potentiometer (or linear encoder), a Hall sensor, laser / echo / or IR distance measurement, and / or a rotary potentiometer (or encoder).

[0165] This disclosure considers that the voltage associated with a PFA may be significantly greater than the voltage associated with RF ablation. Therefore, a PFA device can utilize increased electrical insulation compared to an RF-only device. For example, it may be advantageous to construct the PFA device from a non-conductive material and / or to insulate (or increase the insulation) the conductive elements of the PFA device. As an example, it may be advantageous to electrically insulate the tubular metal shaft extending between the handle and the end effector.

[0166] In some example embodiments, one or more materials used to construct the electrodes can be selected to reduce the likelihood of arc discharge. For example, some electrodes may be constructed entirely of a single material having certain properties. In some example embodiments, a portion of the electrode (e.g., the body portion) may be constructed of a first material and may be at least partially covered (e.g., plated or coated) with a second material different from the first material. Example electrode materials include, but are not limited to, copper, gold, and nickel.

[0167] In some example embodiments, one or more electrodes may be configured to reduce the likelihood of arcing. For example, in some embodiments, arcing is less likely to occur at relatively large radius curved edges than at sharp corners and / or pointed protrusions. In some example embodiments, an array of multiple relatively small electrodes is less likely to arc than a single relatively large electrode.

[0168] Turning Figure 10D Various clamp-type PFA devices according to at least some aspects of this disclosure can utilize ratchet clamping mechanisms. An example of such a ratchet clamping mechanism is illustrated. In the illustrated embodiment, the interaction between the mechanism, specifically the notch and the pin / plate, can be configured to allow movement of the plunger, drive rod, and clamping jaws in the closing direction while preventing movement in the opening direction. When desired, a release lever can be used to retract the pin / plate from the notch, thus allowing movement of the clamping jaws in the opening direction.

[0169] In some example embodiments, the PFA device may include one or more insulator and / or electrode arrangements configured to reduce the likelihood of arcing. While the following example features are individually illustrated and described in the context of the clamp-type PFA device 200, one or more similar features may be used in conjunction with any PFA device configuration, including those substantially similar to the minimally invasive PFA device 300.

[0170] refer to Figure 11A and Figure 11B An example insulator configuration is illustrated, comprising a compressible insulator that at least partially surrounds one or more electrodes. Figure 11C yes Figure 11A and Figure 11B A simplified cross-sectional view of an embodiment. In the illustrated embodiment, the gripper 1102 may include one or more electrodes 1104 disposed on the tissue engagement surface and configured to deliver PFA energy. One or more compressible insulators 1106 may at least partially surround the electrodes 1104. In the illustrated embodiment, the compressible insulator 1106 may be formed from a flexible, compressible, insulating tube attached to the periphery of the gripper 1102. When an object (e.g., tissue) is clamped between the grippers 1102, the compressible insulator 1106 deforms (see...). Figure 11CThis allows electrode 1104 to effectively protrude from the gripper substrate and directly contact the held object. In contrast, when the object is not gripped between the grippers 1102, compressible insulator 1106 protrudes from the gripper substrate and extends outward beyond the reach of electrode 1104 to mitigate accidental discharge to unintended objects. Insulator 1106 can be set to a height to ensure that electrode 1104 never makes direct contact, or to ensure minimal electrode separation. The hardness of 1106 can be selected to achieve a specific compression ratio; it can be relatively harder or softer than the tissue held between the opposing grippers.

[0171] Turning Figure 12A An example insulator configuration is shown to form a shortened electrode exposure area. Figure 12B and Figure 12C yes Figure 12A A simplified cross-sectional view of an embodiment is provided. In the illustrated embodiment, the gripper 1202 may include one or more electrodes 1204 disposed on a tissue contact surface and configured to deliver PFA energy. One or more portions of the electrodes 1204 may be at least partially covered by a fixed or adjustable (sliding) insulator, thereby reducing the tissue contact length of the electrodes. In the illustrated embodiment, a first insulator 1206 may cover the portion of the gripper 1202 near the heel, and / or a second insulator 1208 may cover the portion of the gripper 1202 near the toes. Thus, the generally central portion 1210 of the gripper 1202 may remain uncovered, thereby allowing contact between the electrodes and the target tissue. In the illustrated embodiment, the first insulator 1206 and the second insulator 1208 may be formed of silicone tape wrapped around the gripper 1202. It should be noted that insulators other than silicone may be used to inhibit direct contact between a portion of the electrode 1204 and the tissue.

[0172] refer to Figure 13A The illustration shows an example configuration including insulated grippers. Figure 13B yes Figure 13A A cross-sectional view of an embodiment is shown. In the illustrated embodiment, the gripper 1302 may be constructed of one or more non-conductive (e.g., insulating) materials. Electrodes 1304 may be embedded therein and / or disposed thereon. Therefore, compared to embodiments in which the gripper includes one or more conductive materials exposed to the outside, the risk of arc discharge between the electrodes and the gripper can be reduced.

[0173] Some example embodiments according to at least some aspects of this disclosure may include one or selectively exposed electrodes. For example, some embodiments may include one or more electrodes that may be at least partially covered by one or more relatively soft, deformable insulators. In some example embodiments, one or more insulators may be configured to elastically deform and / or move to at least partially expose one or more electrodes, thereby allowing contact between the electrodes and target tissue. Generally, in some embodiments, the electrodes may remain at least partially covered by the insulator when not in contact with target tissue. In some example embodiments, the insulator may be constructed of a soft, compressible material. The material properties may be selected such that the material moves when clamped onto tissue (e.g., thereby at least partially exposing the electrodes). In some alternative embodiments, the insulator may be constructed of a material having self-healing properties.

[0174] Some example embodiments may be configured to have one or more slits that are configured to facilitate resilient movement and / or electrode exposure. In various embodiments, the electrodes may have any shape, including shapes configured to facilitate exposure. For example, some electrodes may be generally circular, generally rectangular, generally teardrop-shaped, generally parabolic, etc.

[0175] In some example embodiments, the insulator may be overmolded onto the electrode. For example, the insulator may be overmolded onto and / or bonded to a generally smooth filamentary electrode. In some example embodiments, the electrode may include connection features such as lateral through openings configured to facilitate bonding and retention between the insulator and the electrode. In some example embodiments, the electrode may be inserted into an opening in the insulator.

[0176] Some example embodiments may include relatively rigid backing supports provided within or near a relatively soft insulator. For example, the backing may be in the form of a flat plate and / or a slotted block, which can reduce electrode rolling and / or twisting. Some example embodiments may include intermittent strut supports configured to support the electrode relative to an underlying relatively rigid structure (e.g., grippers).

[0177] refer to Figure 13C The illustration shows an alternative embodiment in which electrode 1306 is selectively insulated. In some example embodiments, it is possible to utilize... Figure 13C to replace Figure 13BThe illustrated embodiment shows an exposed electrode configuration. An insulator 1308, which may be constructed of an insulating deformable material, may be arranged to at least partially cover the electrode 1306. As generally described below with reference to other selectively insulated electrodes, the insulator 1308 may deform, for example, upon contact with target tissue to at least partially expose the electrode 1306. In the illustrated embodiment, the insulator 1308 may include a generally longitudinal slit feature 1310, which may facilitate selective exposure of the electrode 1306.

[0178] Turning Figure 14A The illustration includes an example configuration of grippers with selectively insulated electrodes. Figure 14B and Figure 14C When the electrode is in contact with the target tissue Figure 14A A cross-sectional view of an embodiment. In the illustrated embodiment, the gripper 1402 may include one or more electrodes 1404, 1406 on the tissue bonding surface. Reference Figure 14B When the gripper 1402 is not in contact with tissue, one or more deformable insulators 1408, 1410 may at least partially cover one or more electrodes 1404, 1406. In some exemplary embodiments, the insulators 1408, 1410 may be constructed, for example, of flexible silicone or other suitable materials. In the illustrated embodiment, each insulator 1408, 1410 substantially covers the entire length of the corresponding electrode 1404, 1406, wherein a central slit extends along the length of the gripper 1402 between the internal aspects of the insulators 1408, 1410. Reference Figure 14C When the grippers are positioned to contact the target tissue 1412, the target tissue 1412 can deform the insulators 1408 and 1410 (e.g., deform them generally laterally) to expose the electrodes 1404 and 1406, thus allowing the target tissue 1412 to contact the electrodes 1404 and 1406. If the target tissue extends approximately the entire length of the grippers, approximately the entire length of the electrodes 1404 and 1406 can be exposed to contact the target tissue 1412. If the target tissue 1412 does not contact the entire length of the grippers 1402, only the portions of the electrodes 1404 and 1406 close to the target tissue 1412 are exposed. That is, the portions of the electrodes 1404 and 1406 that do not contact the target tissue 1412 or are very close to the target tissue 1412 can remain substantially covered by the insulators 1408 and 1410. Therefore, insulators 1408 and 1410 can reduce the possibility of arc discharge associated with portions of electrodes 1404 and 1406 that are not in contact with the target tissue 1412.

[0179] refer to Figure 15A The illustration includes an alternative example configuration of grippers with selectively insulated electrodes. Figure 15B andFigure 15C When the electrode is in contact with the target tissue Figure 15A A cross-sectional view of an embodiment. In the illustrated embodiment, the gripper 1502 may include one or more electrodes 1504, 1506 on the tissue bonding surface. Reference Figure 15B When the gripper 1502 is not in contact with tissue, one or more deformable insulators 1508, 1510 may at least partially cover one or more electrodes 1504, 1506. In some example embodiments, the insulators 1508, 1510 may be constructed of flexible silicone or other suitable materials. In the illustrated embodiment, each insulator 1508, 1510 substantially covers the entire length of the corresponding electrode 1504, 1506, wherein a central slit extends along the length of the gripper 1502 between the internal aspects of the insulators 1508, 1510. Reference Figure 15C When the grippers are positioned to contact the target tissue 1512, the target tissue 1512 can deform the insulators 1508 and 1510 (e.g., deform them generally laterally) to expose the electrodes 1504 and 1506, thus allowing the target tissue 1512 to contact the electrodes 1504 and 1506. If the target tissue extends approximately the entire length of the grippers, approximately the entire length of the electrodes 1504 and 1506 can be exposed to contact the target tissue 1512. If the target tissue 1512 does not contact the entire length of the grippers 1502, only the portions of the electrodes 1504 and 1506 close to the target tissue 1512 will be exposed. That is, the portions of the electrodes 1504 and 1506 that are not in contact with the target tissue 1512 or are very close to the target tissue 1512 can remain substantially covered by the insulators 1508 and 1510. Therefore, insulators 1508 and 1510 can reduce the likelihood of arc discharge associated with portions of electrodes 1504 and 1506 that are not in contact with the target tissue 1512. In the illustrated embodiment, Figure 15A - The insulators 1508 and 1510 of 15C are different. Figure 14A-14C The insulators 1408 and 1410 are characterized in that insulators 1508 and 1510 are disposed on corresponding elongated base portions 1514 and 1516, which may extend longitudinally along the lateral edges of the gripper 1502. In the illustrated embodiment, the insulators 1508 and 1510 may be integrally formed with the corresponding base portions 1514 and 1516. In some example embodiments, the body of the gripper 1502 may be constructed of a relatively rigid material, and / or the base portions 1514 and 1516 and / or the insulators 1508 and 1510 may be constructed of a relatively flexible and deformable material.

[0180] refer to Figure 16A The illustration includes an alternative example configuration of grippers with selectively insulated electrodes.Figure 16B and Figure 16C When (one or more) electrodes are in contact with the target tissue Figure 16A A cross-sectional view of an embodiment. In the illustrated embodiment, the gripper 1602 may include one or more electrodes 1604 on the tissue bonding surface. Reference Figure 16B When the gripper 1602 is not in contact with tissue, one or more deformable insulators 1606, 1608 may at least partially cover one or more electrodes 1604. In some example embodiments, the insulators 1606, 1608 may be constructed, for example, of flexible silicone or other suitable materials. In the illustrated embodiment, each insulator 1606, 1608 substantially covers the entire length of the electrode 1604, wherein a central slit extends along the length of the gripper 1602 between the internal aspects of the insulators 1606, 1608. Reference Figure 16C When the grippers are positioned to contact the target tissue 1610, the target tissue 1610 can deform the insulators 1606 and 1608 (e.g., deform them generally laterally) to expose the electrode 1604, thus allowing the target tissue 1610 to contact the electrode 1604. If the target tissue extends approximately the entire length of the grippers, approximately the entire length of the electrode 1604 can be exposed to contact the target tissue 1610. If the target tissue 1610 does not contact the entire length of the grippers 1602, only the portion of the electrode 1604 close to the target tissue 1610 is exposed. That is, the portion of the electrode 1604 that does not contact or is very close to the target tissue 1610 can remain substantially covered by the insulators 1606 and 1608. Therefore, the insulators 1606 and 1608 can reduce the likelihood of arcing associated with the portion of the electrode 1604 that does not contact the target tissue 1610. In some exemplary embodiments, insulators 1606 and 1608 may be disposed on corresponding elongated base portions 1612 and 1614, which may extend longitudinally along the lateral edges of the gripper 1602. In the illustrated embodiment, insulators 1606 and 1608 may be integrally formed with the corresponding base portions 1612 and 1614. In some exemplary embodiments, the body of the gripper 1602 may be constructed of a relatively rigid material, and / or the base portions 1612 and 1614 and / or the insulators 1606 and 1608 may be constructed of a relatively flexible and deformable material. In the illustrated embodiment, Figure 16A-16C The configuration is different Figure 15A-15C The configuration may include a single elongated electrode 1604, rather than a pair of generally parallel elongated electrodes 1504, 1506.

[0181] refer to Figure 17A The illustration includes an alternative example configuration of grippers with selectively insulated electrodes.Figure 17B and Figure 17C When the electrode is in contact with the target tissue Figure 17A A cross-sectional view of an embodiment. In the illustrated embodiment, the gripper 1702 may include one or more electrodes 1704 on the tissue bonding surface and one or more deformable insulators 1706, 1708, which are generally similar to those in the reference citation. Figure 16A-16C The corresponding component described. In Figure 17A-17C In the embodiments illustrated, the body of gripper 1702 may be integrally formed with insulators 1706 and 1708. In some embodiments, the body of gripper 1702 may be formed of the same material as insulators 1706 and 1708. Therefore, in some embodiments, the body of gripper 1702 may be deformable. In some example embodiments, when assembled into a clamp-type configuration, the body of gripper 1702 may be mounted to a rigid or more rigid gripper backing.

[0182] Turning Figure 18A The illustration includes an alternative example configuration of grippers with selectively insulated electrodes. Figure 18B and Figure 18C When the electrode is in contact with the target tissue Figure 18A A cross-sectional view of an embodiment. In the illustrated embodiment, the gripper 1802 may include one or more electrodes 1804 on the tissue bonding surface and one or more deformable insulators 1806, 1808, which are generally similar to those in the reference citation. Figure 16A-16C The corresponding components are described. In the illustrated embodiment, insulators 1806 and 1808 may at least partially overlap in the vicinity of electrode 1804. In the illustrated embodiment, the body of gripper 1802 may be integrally formed with insulators 1806 and 1808. In some embodiments, the body of gripper 1802 may be formed of the same material as insulators 1806 and 1808. Therefore, in some embodiments, the body of gripper 1802 may be deformable. In some example embodiments, when assembled into a clamp-type configuration, the body of gripper 1802 may be mounted to a rigid or more rigid gripper backing. In the illustrated embodiment, Figure 17A-17C The configuration is different Figure 18A-18C Another feature is that the gripper 1702 can be bent roughly longitudinally, while the gripper 1802 can be straight roughly longitudinally.

[0183] Figure 18D The illustration includes an example embodiment of a deformable insulator 1810 disposed around an electrode 1812 disposed on a rigid backplate 1814. In the illustrated embodiment, the backplate may include one or more longitudinal grooves 1816, such as for receiving the electrode therein. In some alternative embodiments, the backplate 1814 may be generally flat (e.g., without grooves).

[0184] Figure 18E The illustration shows an example embodiment including spaced-out struts 1818 supporting electrodes 1820 within a deformable insulator 1822. The struts 1818 may be mechanically coupled to a relatively rigid support element, such as the gripper structure of a clamp-type PFA device. In some embodiments, the insulator 1822 may include one or more openings configured to receive the struts 1818 passing through it.

[0185] Some example embodiments may include one or more front protrusion features configured to facilitate movement of insulating material, such as to expose electrodes. For example, such as Figure 18F As illustrated, one or more raised features 1824 are present on the tissue contact surface 1826. These features can be arranged to contact the target tissue before other portions of the insulators 1828, 1830, thereby causing the insulators 1828, 1830 to move away from the electrode 1832 and expose the electrode 1832.

[0186] Figure 18G The illustration shows an alternative example embodiment in which the deformable insulator 1834 can be segmented. In the illustrated embodiment, in addition to the longitudinal slit 1838, one or more generally lateral transverse cuts 1836 (e.g., slits) are provided. Therefore, the tissue-contacting segment 1840 of the insulator 1834 can be more easily removed from the electrode 1842, while the tissue-non-contacting segment 1840 of the insulator 1834 can remain in place (e.g., at least partially covering the electrode 1842).

[0187] This disclosure considers the potential formation of microbubbles when a high-voltage electrical pulse is delivered during PFA (Procedure for Aging). Generally, microbubbles can comprise multiple thin liquid spheres, each encapsulating a small pouch of gas. Microbubbles can be formed, for example, through liquid evaporation, cavitation, and / or electrolysis. Microbubble formation can generally be undesirable because, after formation, microbubbles may travel across the bloodstream and obstruct small blood vessels, potentially leading to unintended tissue damage and / or organ dysfunction. Microbubbles may also cause asymptomatic brain events, such as brain injury occurring during medical procedures or interventions, without producing any obvious symptoms.

[0188] This disclosure considers that, although PFA is generally considered non-thermal because it does not rely on high temperatures to ablate tissue, in some cases, applying PFA energy may result in tissue heating. Generally, the duration, intensity, and / or frequency of the PFA signal can affect the degree of tissue heating. In some cases, the composition and / or structure of the tissue may affect heating, such as the rate at which heat can be transferred and dissipated. In some cases, cooling methods can be used to reduce tissue temperature. For example, rinsing with a cooling fluid such as saline and / or using a radiator or cooling conduit can reduce the likelihood of undesirable heating. Alternatively, in a vacuum chamber embodiment, a fluid flow through the vacuum chamber can be used to cool the electrode and tissue surface. An on / off electrode duty cycle can be achieved by alternating electrode pairs.

[0189] This disclosure contemplates that PFA and RF ablation may be associated with different mechanisms of action and / or potentially different advantages and / or disadvantages. In some exemplary embodiments according to at least some aspects of this disclosure, these differences can be utilized to facilitate desired results. For example, some illustrative embodiments may be configured to perform both PFA and RF ablation on a specific target tissue. In some exemplary embodiments, PFA and RF ablation may be performed using at least one common electrode. In some exemplary embodiments, PFA and RF ablation may be performed using different electrodes. Generally, any system, device, electrode, insulation configuration, etc., described herein can be used in conjunction with the delivery of either or both of RF and PFA.

[0190] For example, some embodiments allow the user to choose between a PFA-only mode and an RF-only mode. Thus, the user can select the desired ablation mode for a specific ablation. For instance, a surgeon can select PFA and / or RF ablation based at least in part on the location of the ablation (e.g., proximity to sensitive non-target tissue) and / or the type of target tissue.

[0191] Some example embodiments can be configured to create lesions using both PFA and RF ablation forms. For example, in some cases, it may be advantageous to combine epicardial RF ablation with endocardial PFA. The resulting ablation can be a combination of partial PFA and partial RF, which meet within the tissue thickness in any mixed ratio to create a full-thickness lesion. The PFA can extend from one surface into the tissue thickness, while the RF extends from the opposite surface. Alternatively, the RF lesion may be formed partially or entirely centrally within the tissue thickness, while the PFA extends outward to the tissue surface to complete the lesion. This mixed-form approach can create transmural lesions in the target tissue while benefiting from the advantages associated with each individual form. For example, in some cases, using PFA in the endocardium can avoid some of the potential disadvantages of using RF ablation in close proximity to the blood, and / or using RF ablation in the epicardium can facilitate thermal ablation of some target autonomic tissue. In some example embodiments, PFA can be applied bidirectionally (e.g., in the endocardium and in the epicardium), and RF ablation can be applied unidirectionally (e.g., only in the epicardium). In some example implementations, both PFA and RF ablation can be performed approximately across the entire tissue thickness.

[0192] In some example embodiments, PFA can be performed prior to RF ablation, which can facilitate faster RF ablation due to the increased tissue conductivity caused by PFA. In some example embodiments, RF ablation can be performed prior to PFA. In some example embodiments, RF and PF ablation can be performed simultaneously with interrupted alternating and / or overlapping deliveries.

[0193] This disclosure contemplates that PFA and cryoablation may be associated with different mechanisms of action and / or different advantages and disadvantages. In some exemplary embodiments according to at least some aspects of this disclosure, these differences can be utilized to facilitate desired results. For example, some illustrative embodiments may be configured to perform both PFA and cryoablation, but not necessarily simultaneously.

[0194] For example, some embodiments allow users to choose between a PFA-only mode and a cryoablation-only mode. Thus, users can select the desired ablation method for a specific ablation procedure. For instance, surgeons can select PFA and / or cryoablation based at least in part on the location of the ablation and / or the type of target tissue.

[0195] Some example embodiments can be configured to create damage using both PFA and cryoablation. This hybrid approach can create transmural damage in the target tissue while benefiting from the advantages associated with each individual form. In some example embodiments, PFA can be performed prior to cryoablation. In some example embodiments, cryoablation can be performed prior to PFA. In some example embodiments, PFA can be performed at any point in time or throughout the entire duration of cryoablation. Temperature measurements or setpoints can be used as feedback, or they can be left unused. In some example embodiments, cryoablation can be applied at a therapeutic level. That is, cryoablation on its own may be sufficient to induce permanent damage in the target tissue. In other embodiments, cryoablation can be applied below a therapeutic level. That is, cryoablation on its own may affect the tissue in a substantially reversible manner. In some cases, performing cryoablation prior to PFA may affect (e.g., improve or enhance) subsequent PFA. For example, the target tissue treated with cryoablation receives PFA energy more efficiently, whether it is fully reheated or still cooled below body temperature, or PFA energy can be conducted through the target tissue in different ways, or the lower tissue temperature achieved by cryoablation can offset or reduce the thermal temperature rise achieved by using PFA.

[0196] This disclosure considers that, in some cases, PFA-induced damage may not be readily visible on the target tissue immediately or shortly after the delivery of PFA energy. In some cases, due to cell death and tissue reaction, PFA damage may not be readily visible or detectable for days to weeks. Therefore, the presence, location, and / or extent of PFA damage may not be readily apparent or detectable to the user during the ablation procedure. This disclosure considers that this lack of immediate visibility and / or detectability may increase the difficulty of forming long, continuous lesions by performing multiple overlapping ablations.

[0197] Return to Figure 1 In some example embodiments according to at least some aspects of this disclosure, the PFA device 104 can be operated to form immediately visible thermal damage along with the formation of PFA damage. For example, a PFA damage can be formed, and the corresponding thermal damage can then be formed using RF ablation and / or cryoablation (e.g., without moving the end effector 132 between the PFA and the RF or cryoablation). Alternatively, in addition to irreversible electroporation ablation of surrounding tissue, high-voltage PFA can be used to form localized thermal damage. Alternatively, PFA followed by a high-voltage pulse or pulse train can be performed, which may not electrically perforate the tissue but may form thermal damage within the tissue. In some example embodiments, thermally induced damage may be advantageous because it can ablate surface clusters.

[0198] refer toFigure 19A The diagram illustrates an example of damage including PFA zone 1902 and thermal ablation zone 1904. Figure 19B yes Figure 19A A cross-sectional view of the damage.

[0199] Figure 19C This is a top view of an example damage formed using a PFA + RF device according to at least some aspects of this disclosure, as shown with a PFA zone 1902 and a thermal ablation zone 1904.

[0200] Various tissue contact configurations can be utilized according to example embodiments of at least some aspects of this disclosure.

[0201] Some example embodiments can be configured to utilize contact force applied by an operator to induce contact with the desired tissue. For example, during the application of PFA energy, an operator can manually hold the device against the target tissue in a pen-like configuration. Similarly, a surgical robot can be used to apply the PFA device against the target tissue.

[0202] Some embodiments utilizing mechanical configurations can typically be constructed in the form of a fixture. For example, see... Figure 2 Examples of this implementation include those utilizing a snare. Some embodiments employing mechanical configurations may utilize a snare. Figure 19D The illustration shows an example of a snare fixture, number 1910.

[0203] Some example embodiments may utilize screws for tissue joining. Figure 19E The illustration shows an example of a roughly spiral screw-engaged element 1920 configured to penetrate target tissue 1924 for grippers or electrodes 1922.

[0204] Some exemplary embodiments may utilize cooperating magnetic elements for tissue bonding. For example, various embodiments described in International Application No. PCT / US2022 / 082057, filed December 20, 2022 (which was published on July 6, 2023 as International Application No. WO2023129842 entitled "MAGNETICALLY COUPLED ABLATION COMPONENTS"), entitled "MAGNETICALLY COUPLED ABLATION COMPONENTS", may be used in conjunction with embodiments according to at least some aspects of this disclosure, which is incorporated herein by reference.

[0205] Some example embodiments can be configured to puncture tissue. For example, see... Figure 4A-4C The needle-type embodiment.

[0206] Some example embodiments can be configured to utilize vacuum for tissue bonding. For example, see... Figure 3A and Figure 3B Examples of implementations.

[0207] Some example embodiments can utilize tissue freezing for tissue bonding. For instance, embodiments incorporating cryogenic capabilities can be positioned to contact target tissue. The tissue may be at least partially frozen or significantly cooled (therapeutic or subtherapeutic), which may cause the tissue bonding probe to attach to the target tissue. While the probe is attached to the target tissue and thus maintains contact, PFA energy can be applied. After the desired PFA and / or cryogenic effect has been achieved, the tissue can be thawed or heated, and the probe can be removed from the tissue.

[0208] refer to Figure 20 Some example embodiments may utilize one or more expandable structures to generate tissue contact force. In the illustrated embodiment, the PFA device 2002 may include one or more electrodes 2004, 2006 and / or one or more expandable structures 2008 on the tissue engagement surface. In the illustrated embodiment, the expandable structure 2008 may be disposed substantially opposite to the electrodes 2004, 2006. In operation, the PFA device 2002 may be positioned between the target tissue 2010 and the opposing tissue 2012. The expandable structure 2008 may expand from a collapsed configuration (dashed line) to an expanded configuration (solid line). Expanding the expandable structure 2008 may cause it to contact the opposing tissue 2012, thereby pressing the tissue engagement surface including the electrodes 2004, 2006 against the target tissue 2010. The expansion of the expandable structure 2008 may be controlled as needed to achieve the desired contact between the electrodes 2004, 2006 and the target tissue 2010. After one or more ablation operations, the expandable structure 2008 may collapse. In some example embodiments, the expandable structure may be expandable, such as by a fluid (e.g., gas and / or liquid). In example embodiments, target tissue 2010 may include myocardium, and relative tissue 2012 may include pericardium.

[0209] Some example embodiments of at least some aspects of this disclosure may include multiple electrodes. Generally, any embodiment described herein may include one or more electrodes unless explicitly stated otherwise. While some embodiments may have been described in conjunction with specific exemplary uses of particular individual electrodes, it should be understood that any electrode in any embodiment can be used for any purpose, regardless of how it may be described in a particular example. For example, in some cases, an electrode described as an ablation electrode may be used for pacing, stimulation, mapping, and / or sensing. Similarly, in some cases, an electrode described as a pacing, stimulation, mapping, and / or sensing electrode may be used for ablation. Furthermore, regardless of whether it is specifically described herein in conjunction with specific example embodiments, it should be understood that any embodiment of at least some aspects of this disclosure may include additional electrodes, such as electrodes for pacing, stimulation, mapping, and / or sensing.

[0210] Some example embodiments based on at least some aspects of this disclosure can be used in conjunction with procedures for the treatment of various arrhythmias. For example, ablation can be performed on various target tissues, including the cardiac autonomic nervous system (e.g., ganglion plexuses, nodes, and / or conduction pathways) and / or basal cardiac tissue (e.g., atria and / or ventricles).

[0211] Generally, procedures involving any part of the heart using the devices and / or methods disclosed herein are within the scope of this disclosure. For example, procedures involving the right atrium may be performed in conjunction with treatment for inappropriate sinus tachycardia (e.g., crest, inferior vena cava, and / or superior vena cava), atrial fibrillation (e.g., maze surgery injury - right side), and / or Wolf-Parkinson-White syndrome. Procedures involving the right ventricle may be performed, for example, in conjunction with treatment for ventricular tachycardia (e.g., right ventricular posterior wall, right ventricular lateral free wall, right ventricular anterior portion, diaphragm, right ventricular papillary muscle, and / or right ventricular outflow tract), partial ventricular contractions (e.g., right ventricular outflow tract diaphragm, right ventricular basal segment, and / or right ventricular outflow tract free wall), and / or Brugda syndrome (e.g., right ventricular outflow tract). Procedures involving the left atrium may be performed in conjunction with treatments for atrial fibrillation (e.g., Marshall ligament, top and bottom lines, posterior wall of the left atrium, isthmus and / or autonomic nerves (ganglionic plexus)) and / or left atrial appendage isolation (e.g., left atrial appendage orifice). Procedures involving the left ventricle may be performed, for example, in conjunction with syncope (e.g., autonomic nerves (ganglionic plexus)), atrial tachycardia (e.g., any location in the left ventricle), atrial flutter (e.g., mitral valve), Wolf-Parkinson-White syndrome (e.g., atrioventricular groove), partial ventricular contraction (e.g., left ventricular outflow tract and / or aortic root), hypertension (e.g., any location in the left ventricle) and / or ventricular tachycardia (e.g., posterior wall of the left ventricle, lateral free wall of the left ventricle, anterior part of the left ventricle, diaphragm, left ventricular papillary muscles and / or left ventricular roof). Procedures involving the right ventricular / left ventricular septum can be performed, for example, in conjunction with ventricular tachycardia (e.g., combined right and left ventricular lesions). It should be understood that the foregoing list is merely exemplary and should not be considered limiting.

[0212] Some example embodiments of at least some aspects of this disclosure can be used in conjunction with nerve block procedures. For example, peripheral nerves can be ablated to cause temporary, but fully recoverable, loss of sensory nerve function. Ablation may result in axonal transection, a degree of nerve damage according to the Seden classification, in which the axon and myelin sheath are destroyed, but at least some surrounding tubular structures (such as the endoneurium, perineurium, nerve bundle, and / or epineurium) remain intact. The subsequent Wallerian degeneration (the process in which the entire length of the nerve segment distal to the ablation lesion is removed) may take approximately one week. Nerve regeneration begins from the proximal segment and continues along the intact structural components at an average rate of 1-3 mm / day until the tissue is re-innervated. This process may take weeks to months, depending on the extent of the ablation lesion in the tissue. Because it preserves the nerve's structure, such procedures may not be associated with neuroma formation.

[0213] Local analgesia for nerves (e.g., intercostal nerves) aims to manage discomfort caused by incisions, surgical muscle rupture, nerve compression due to surgical equipment (e.g., retractors) and surgical retainers (e.g., sutures), and pain caused by any openings formed by tube or cannula sites. In an exemplary form, an exemplary procedure includes nerve ablation for post-thoracotomy pain, including ablation of the intercostal nerves. Next is an exemplary procedure for nerve block in response to thoracotomy, which is effective for pain management and can be applied to any nerve in an animal.

[0214] It is recommended to perform nerve ablation procedures as early as possible in surgical procedures, such as before or immediately after inducing thoracotomy. The target nerve (such as an intercostal nerve) can be located in the incisional intercostal space (e.g., between the ribs), preferably at the border of the innermost intercostal muscle and the membranous portion of the internal intercostal muscle. A location can be chosen proximal to the lateral cutaneous branch, but at least 2 cm from the ganglion and / or at least 4 cm from the spine.

[0215] The ablation device can be placed directly on top of the nerve, optionally at a slight angle, ensuring the nerve is directly beneath the ablation element. Prior to ablation, the ablation device can be pressed into the costal groove with sufficient pressure to create tissue compression, thereby achieving stability and reduced local perfusion. Appropriate pressure can be sufficient to produce a whitening effect when pressed against the skin. In some example embodiments, a needle-type PFA device can be used. In some example embodiments, a pen-type PFA device can be used. In some example embodiments, a minimally invasive PFA device, such as a PFA device providing vacuum stabilization capabilities, can be used.

[0216] After positioning the ablation device to contact or closely approximate the nerve, the device can be activated to ablate the nerve. The ablation sequence can be repeated at another location on the same nerve (or at different locations on different nerves), and as needed, to achieve appropriate pain management outcomes. Generally, some of the exemplary nerve ablation procedures described above can be repeated on the intercostal nerves located in each of the third to ninth intercostal spaces.

[0217] In some example methods according to at least some aspects of this disclosure, nerve ablation may be provided in conjunction with amputation of a limb and / or four extremities. This disclosure contemplates that, in some cases, nerve ablation may be performed at some point after the amputation procedure (e.g., weeks, months, or years), such as after the patient experiences significant pain.

[0218] In some example methods according to at least some aspects of this disclosure, nerve ablation can be performed simultaneously with an amputation procedure. For example, during the amputation procedure, the nerve can be identified. The nerve can be dissected to separate it from adjacent tissues, such as nearby blood vessels. The location of the nerve slice can be determined. In some cases, the nerve may be retracted distally. The location of the nerve ablation can be determined, such as proximal to the location of the nerve transection. The nerve can be ligated at the ablation location, for example, using an ablation device. Ablation of the nerve can be performed using an ablation device by contacting a pen-like device or by capturing it between clamp-like or grasper-like devices. In some cases, one or more ablation cycles can be performed. The ablation device can be removed from the nerve. The nerve can be sliced ​​at the nerve slice location.

[0219] Therefore, mechanical damage to the nerve (e.g., transection of the nerve at the nerve slicing site) may occur at a distance distal to the nerve ablation site. Since the nerve can slowly regenerate distally from the ablation site towards the nerve slicing site, it may take a considerable amount of time before reaching the nerve slicing site via the regenerating nerve. During this time, damaged tissue near the nerve slicing site may heal. Therefore, when the nerve reaches the nerve slicing site via the regenerating nerve, it may be surrounded by relatively healed tissue, thus reducing the likelihood and / or severity of neuroma formation. Additionally, pain and other sensations from locations distal to the ablation site may lessen during the nerve regeneration period, thus reducing the need for additional postoperative pain management.

[0220] Some exemplary embodiments according to at least some aspects of this disclosure may be used in conjunction with ablation of target tissues other than cardiac and neural tissues. For example, some embodiments may be used in conjunction with ablation of tissues including liver tissue, kidney tissue, and / or brain tissue.

[0221] Turning Figure 21The illustrations may be simplified block diagrams, for example, used to illustrate various PFA and / or RF ablation devices and / or algorithms according to at least some aspects of this disclosure.

[0222] refer to Figure 22 Example PFA device 2200 can be configured for vacuum stabilization and / or unipolar energy delivery. The construction and / or operation of the illustrated embodiments can be generally similar to those described in U.S. Patent No. 10,413,355, issued September 17, 2019, entitled “VACUUM COAGULATION PROBES,” which is incorporated herein by reference. References Figure 5R and Figure 22 Some example embodiments may include a generally spiral electrode 2202 disposed within a vacuum chamber, which can be used to bond target tissue using a vacuum, and / or may be supplied with a brine solution, which can facilitate cooling and / or bonding.

[0223] refer to Figure 23 In some example embodiments according to at least some aspects of this disclosure, one or more PFA energy parameters (such as those described herein) may vary at least in part based on one or more measured parameters. For example, one or more measurements may be performed before PFA energy is delivered, and such measured values ​​may be used to determine one or more PFA energy parameters to be delivered. In some example embodiments, one or more measurements may be performed in conjunction with the delivery of PFA energy (e.g., during and / or between PFA pulses), and such measured values ​​may be used to determine whether to continue or stop PFA energy delivery, and / or to determine whether to adjust one or more PFA energy parameters.

[0224] In some embodiments involving clamp-type PFA devices, one or more parameters associated with the distance between the grippers can be used to at least partially determine one or more PFA energy parameters. For example, one or more PFA energy parameters can be controlled based on parameters associated with the distance between relative grippers. For example, in one embodiment, the distance between the grippers can be measured and used to determine the PFA energy potential (e.g., the maximum voltage delivered). In some such embodiments, a larger measured gripper distance may result in a larger PFA energy potential. Therefore, in some embodiments, a desired transmembrane cell voltage potential can be achieved across a series of gripper closure distances.

[0225] In some example embodiments, at least one PFA energy parameter may increase as the measured parameter increases. In some example embodiments, at least one PFA energy parameter may decrease as the measured parameter decreases. In some example embodiments, at least one PFA energy parameter may increase as the measured parameter decreases. In some example embodiments, at least one PFA energy parameter may decrease as the measured parameter increases.

[0226] In some example embodiments, at least one PFA energy parameter may vary substantially linearly with the measured parameter. In some example embodiments, at least one PFA energy parameter may vary substantially non-linearly with the measured parameter.

[0227] For example, but not limited to, one or more PFA energy parameters (such as those described herein) may be determined and / or varied based at least in part on one or more measurements of voltage, current, inductance, impedance, conductivity, resistance, or temperature.

[0228] In some example embodiments according to at least some aspects of this disclosure, one or more PFA energy parameters (such as those described herein) may vary at least in part based on one or more selected parameters. Such selected parameters may be preset when constructing the device or unit for a particular end use, or may be selected by the user before and / or during use. For example, one or more PFA energy parameters may be at least partially determined using tissue type, cell density, and / or tissue compressibility / compressibility.

[0229] In some example embodiments, two or more measured and / or selected parameters may be used in combination to determine one or more PFA energy parameters. For example, a selected tissue type (e.g., which may be associated with known tissue compressibility and / or cell density values), a measured gripper closure distance, and / or a measured gripper closure force may be used in combination to at least partially determine at least one PFA energy parameter, such as the maximum potential. In some embodiments, two or more measured and / or selected parameters may be weighted equally when determining at least one PFA energy parameter. In some embodiments, two or more measured and / or selected parameters may be weighted unequally when determining at least one PFA energy parameter. In some example embodiments, different selected and / or measured parameters may be used to at least partially determine different PFA energy parameters. In some example embodiments, different selected and / or measured parameters may be weighted differently along with at least partially determining different PFA energy parameters.

[0230] Generally, any one or more PFA energy parameters described herein can be determined and / or changed based at least in part on the selection and / or measurement of any parameters or conditions described herein.

[0231] The following patent references provide background for this disclosure and are incorporated herein by reference in their entirety: U.S. Patent No. 9,072,518, entitled "HIGH-VOLTAGE PULSE ABLATION SYSTEMS AND METHODS," published July 7, 2015; U.S. Patent No. 9,474,574, entitled "STABILIZED ABLATION SYSTEMS AND METHODS," published October 25, 2016; U.S. Patent No. 11,628,007, entitled "CRYOPROBE," published April 18, 2023; U.S. Patent No. 10,413,355, entitled "VACUUM COAGULATION PROBES," published September 17, 2019; and U.S. Patent No. 10,413,355, entitled "ABLATION DEVICES AND METHODS," published May 5, 2022. The patents filed herein include U.S. Patent Application No. 2022 / 0133400 entitled “OFUSE”; U.S. Patent Application No. 2019 / 0159835 entitled “CRYOPAD”, published May 30, 2019; and International Application No. PCT / US2022 / 082057 entitled “MAGNETICALLY COUPLED ABLATION COMPONENTS”, filed December 20, 2022 and published July 6, 2023. Generally, any feature or improvement described herein may be used in conjunction with embodiments described in these patent references, and any feature, element, or method described in these patent references may be used in conjunction with any embodiment described herein.

[0232] Unless otherwise specified, it will be understood that the descriptions of any structure, function, and / or method in any illustrative embodiment herein are applicable to any other illustrative embodiment. More generally, any one or more features of any one or more of the other example embodiments described herein are utilized within the scope of this disclosure. Therefore, any feature or any combination of embodiments described herein is within the scope of this disclosure.

[0233] Based on the foregoing description and abstract, it will be apparent to those skilled in the art that while the methods and apparatus described herein constitute exemplary embodiments according to this disclosure, it should be understood that the scope of disclosure contained herein is not limited to the precise embodiments described above, and changes may be made without departing from the scope defined by the appended claims. Similarly, it should be understood that it is not necessary to satisfy any or all of the identified advantages or purposes disclosed herein in order to fall within the scope of the claims, as inherent and / or unforeseen advantages may exist, even if they may not be explicitly stated herein.

Claims

1. A pulsed field ablation actuator, comprising: An electrode, the electrode including an electrode surface for delivering an electric current to anatomical tissue; as well as, A deformable insulator selectively covers the electrode surface, the deformable insulator being configured to deform upon contact with the anatomical tissue to expose the electrode surface.

2. The pulsed field ablation actuator of claim 1, wherein the deformable insulator includes a slit at least partially occupied by the electrode.

3. The pulse field ablation actuator according to claim 2, wherein: The slit extends longitudinally along the main dimension of the deformable insulator; and... The electrode extends longitudinally for most of its length within the slit.

4. The pulse field ablation actuator according to claim 1, further comprising a rigid backing, wherein the electrode and the deformable insulator are mounted to the rigid backing.

5. The pulse field ablation actuator of claim 4, wherein the deformable insulator is mounted to the rigid backing using a movable hinge.

6. The pulse field ablation actuator according to claim 4, wherein the deformable insulator is embedded within the rigid backing.

7. The pulsed field ablation actuator of claim 1, wherein the deformable insulator includes a raised feature configured to concentrate the contact force generated due to contact with the anatomical tissue and to accelerate the deformation of the deformable insulator.

8. The pulsed field ablation actuator according to claim 7, wherein the protrusion feature comprises a plurality of protrusion features, wherein at least two of the plurality of protrusion features are on opposite sides of the electrode.

9. The pulse field ablation actuator according to claim 7, wherein: The plurality of protruding features include longitudinal ribs; and... The longitudinal ribs extend approximately parallel to the electrodes.

10. The pulse field ablation actuator according to claim 1, wherein the deformable insulator comprises an elastomer.

11. The pulsed field ablation actuator of claim 10, wherein the elastomer comprises silicone.

12. The pulse field ablation actuator according to claim 1, wherein: The electrode is segmented into multiple electrodes; The deformable insulator is segmented into multiple deformable insulator sections; Each of the plurality of electrodes includes an electrode surface selectively covered by at least one of the plurality of deformable insulator segments; and, Only those deformable insulator segments that are in contact with the anatomical tissue among the plurality of deformable insulator segments are deformed to expose those electrodes that are covered by the contacted plurality of deformable insulator segments.

13. The pulse field ablation actuator according to claim 1, wherein: The deformable insulator is segmented into multiple deformable insulator sections; The electrode surface is selectively covered by at least one of the plurality of deformable insulator segments; and, Only those deformable insulator segments that are in contact with the anatomical tissue among the plurality of deformable insulator segments deform to expose those aspects of the electrode surface that are covered by the contacted plurality of deformable insulator segments.

14. The pulse field ablation actuator of claim 1, further comprising a cryogenic conduit configured to supply cryogenic fluid to the cryogenic tissue contact portion.

15. The pulsed field ablation actuator according to claim 14, wherein the cryogenic tissue contact portion includes the electrode surface of the electrode.

16. The pulsed field ablation actuator of claim 1, further comprising a radio frequency electrode adapted to deliver radio frequency energy to the anatomical tissue.

17. The pulsed field ablation actuator of claim 16, wherein the radio frequency electrode is selectively covered by the deformable insulator.

18. A method for performing pulsed field tissue ablation, the method comprising: The pulsed field ablation actuator is repositioned to be close to the target tissue, wherein the pulsed field ablation actuator includes an electrode having an ablation surface covered by a deformable insulator; The pulsed field ablation actuator is repositioned to make full contact with the target tissue, wherein full contact with the target tissue is operable to deform the deformable insulator and expose the ablation surface of the electrode that was previously covered by the deformable insulator; When in full contact with the target tissue, a current is supplied to the electrode to induce electroporation of the target tissue; as well as, The pulsed field ablation actuator is repositioned to no longer make sufficient contact with the target tissue, wherein the insufficient contact with the target tissue is operable to deform the deformable insulator and cover the previously uncovered ablation surface of the electrode.

19. The method of claim 18, wherein: The target tissue is heart tissue; and... The contact mentioned is epicardial contact.

20. The method of claim 18, wherein: The target tissue is nerve; and... The contact is contact with at least one of an intact nerve and a dissected nerve.

21. The method according to claim 18, wherein: The target tissue is the intercostal nerve; and... The method is performed simultaneously with thoracotomy.

22. The method of claim 18, wherein: The target tissue is heart tissue; and... The contact mentioned is endocardial contact.

23. The method of claim 18, wherein: The pulsed field ablation actuator includes a first gripper and a second gripper, wherein the electrode includes a first electrode portion on the first gripper and a second electrode portion on the second gripper; and, Repositioning the pulsed field ablation actuator to fully contact the target tissue includes: contacting the first electrode portion with epicardial cardiac tissue and contacting the second electrode portion with endocardial cardiac tissue, such that full contact with the epicardial and endocardial cardiac tissues is operable to deform the deformable insulator and expose the first and second electrode portions previously covered by the deformable insulator.

24. The method of claim 18, further comprising: Cryoablation is performed simultaneously with the electroporation to destroy the target tissue or tissue in its vicinity.

25. The method of claim 18, further comprising: Radiofrequency ablation is performed simultaneously with the electroporation to destroy the target tissue or tissue in its vicinity.

26. The method of claim 18, wherein: In the absence of sufficient contact between the target tissue and the deformable insulator, the deformable insulator is located between the ablation surface of the electrode and the target tissue; and, When sufficient contact is made between the target tissue and the deformable insulator, the deformable insulator is no longer located between the ablation surface of the electrode and the target tissue.

27. The method of claim 26, wherein when the target tissue is in full contact with the deformable insulator, the tissue contact surface of the electrode protrudes from the deformable insulator.

28. The method according to claim 26, wherein: The electrode is segmented into multiple electrodes, each of which has a tissue contact surface; The deformable insulator is segmented into multiple deformable insulator segments, wherein each of the multiple electrodes is selectively covered by at least one of the multiple deformable insulator segments; and, When the target tissue makes full contact with each of the plurality of deformable insulator segments, each of the plurality of deformable insulator segments is operable to expose the corresponding tissue contact surface of the plurality of electrodes.

29. The method according to claim 18, wherein: The deformable insulator is segmented into multiple deformable insulator segments, wherein the ablation surface is selectively covered by at least one of the multiple deformable insulator segments; In the absence of sufficient contact between the target tissue and the deformable insulator, the deformable insulator is located between the ablation surface of the electrode and the target tissue; and, When the target tissue makes full contact with each of the plurality of deformable insulator segments, each of the plurality of deformable insulator segments is operable to expose a portion of the ablation surface.

30. A method for suppressing unintended arc discharge across a pulsed field ablation electrode, the method comprising: The pulsed field ablation electrode is covered with a deformable insulator configured to change its shape between a first shape and a second shape in response to the application of a sufficient external force, the first shape covering the tissue contact surface of the pulsed field ablation electrode and the second shape not covering the tissue contact surface of the pulsed field ablation electrode.

31. Any apparatus, method or combination thereof disclosed herein.

32. Any combination of any two or more of the preceding claims.

33. Any combination of elements from one or more of the preceding claims.

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