Electrode retention features for catheter instruments

Abstract

This invention relates to electrode holding features for catheter devices. A device includes an elongated flexible shaft and an end effector. The shaft has a proximal end and a distal end. The end effector is positioned at the distal end of the shaft. The end effector includes a body, an electrode, and an adhesive material. The electrode defines one or more laterally oriented openings. The adhesive material secures the electrode to the body. A portion of the adhesive material is disposed in at least one of the one or more laterally oriented openings.

Description

Background Technology

[0001] Cardiac arrhythmias, such as atrial fibrillation, occur when areas of cardiac tissue abnormally conduct electrical signals. Procedures for treating arrhythmias involve surgically interrupting the conduction pathways used for such signals. By selectively applying electrical energy to cardiac tissue, it is possible to stop or alter the propagation of unwanted electrical signals from one part of the heart to another. Some such ablation treatments may include radiofrequency (RF) ablation using alternating current (AC) energy; and / or irreversible electroporation (IRE) via pulsed field direct current (DC) energy (e.g., pulsed field ablation (PFA)). The ablation process provides a blockage of unwanted electrical pathways by creating an electrically insulating lesion or scar tissue that effectively blocks the communication of abnormal electrical signals across the ablated tissue.

[0002] In some procedures, a catheter with one or more electrodes may be used to deliver ablation within a patient. The catheter may be inserted into a major vein or artery (e.g., the femoral artery) and then advanced to position the electrodes within the heart or in structures adjacent to the heart (e.g., the pulmonary veins). One or more electrodes may be positioned to contact cardiac tissue or other vascular tissue and then activated with electrical energy to ablate the contacted tissue (e.g., via RF energy, IRE, etc.). In some cases, the electrodes may be bipolar. In some other cases, a monopolar electrode may be used in conjunction with a grounding pad or other reference electrode in contact with the patient. Flushing may be used to absorb heat from the components of the ablation catheter and to prevent blood clots from forming near the tissue treatment site.

[0003] Examples of ablation catheters are described in the following documents: U.S. Patent No. 8,747,351, entitled "Catheter with Multi-Functional Control Handle Having Linear Mechanism," published June 10, 2014, the disclosure of which is incorporated herein by reference in its entirety; U.S. Patent No. 8,956,353, entitled "Electrode Irrigation Using Micro-Jets," published February 17, 2015, the disclosure of which is incorporated herein by reference in its entirety; U.S. Patent No. 9,220,433, entitled "Catheter with Variable Arcuate Distal Section," published December 29, 2015, the disclosure of which is incorporated herein by reference in its entirety; and U.S. Patent No. 20, entitled "Catheter with Soft Distal Tip for Mapping and Ablating Tubular," published November 20, 2018. The disclosures of U.S. Patent No. 10,130,422 entitled “Region” are incorporated herein by reference in their entirety; the disclosures of U.S. Patent No. 10,702,177 entitled “Catheter with Bipole Electrode Spacer and Related Methods”, published on July 7, 2020, are incorporated herein by reference in their entirety; the disclosures of U.S. Patent No. 10,743,932 entitled “Integrated Ablation System using Catheter with Multiple Irrigation Lumens”, published on August 18, 2020, are incorporated herein by reference in their entirety; and the disclosures of U.S. Patent No. 11,559,349 entitled “Ablation Catheter with a Flexible Printed CircuitBoard”, published on January 24, 2023, are incorporated herein by reference in their entirety.

[0004] Some catheter ablation procedures can be performed after electrophysiological (EP) mapping to identify tissue areas that should be targeted for ablation. Such EP mapping may involve the use of sensing electrodes on a catheter (e.g., the same catheter used to perform the ablation or a dedicated mapping catheter). These sensing electrodes monitor electrical signals emanating from conductive endocardial tissue to precisely locate the site of abnormally conductive tissue leading to arrhythmias. Examples of EP mapping systems are described in U.S. Patent No. 5,738,096, entitled “Cardiac Electromechanics,” issued April 14, 1998, the disclosure of which is incorporated herein by reference in its entirety. Examples of EP mapping catheters are described in the following documents: U.S. Patent No. 9,907,480, entitled “Catheter Spine Assembly with Closely-Spaced Bipole Microelectrodes,” published March 6, 2018, the disclosure of which is incorporated herein by reference in its entirety; U.S. Patent No. 10,130,422, entitled “Catheter with Soft Distal Tip for Mapping and Ablating Tubular Region,” published November 20, 2018, the disclosure of which is incorporated herein by reference in its entirety; and U.S. Patent No. 10,702,177, entitled “Catheter with Bipole Electrode Spacer and Related Methods,” published July 7, 2020, the disclosure of which is incorporated herein by reference in its entirety.

[0005] Some catheter ablation procedures can be performed using image-guided surgery (IGS) systems. IGS systems allow physicians to visually track the catheter's position within the patient's body in real time, relative to images of the patient's anatomy. Some systems offer a combination of EP mapping and IGS functionality, including the CARTO 3 from Biosense Webster, Inc., Irvine, California. ® Systems. Examples of catheters constructed for use with IGS systems are disclosed in the following documents: U.S. Patent No. 9,480,416, issued November 1, 2016, entitled “Signal Transmission Using Catheter Braid Wires,” the disclosure of which is incorporated herein by reference in its entirety; and various other references cited herein.

[0006] Although several catheter systems and methods have been manufactured and used, it is believed that no one had manufactured or used the inventions described, shown and claimed herein before the inventors. Attached Figure Description

[0007] The following figures and detailed descriptions are intended to be illustrative only and are not intended to limit the scope of the invention as contemplated by the inventors.

[0008] Figure 1 A schematic diagram depicts a medical procedure for inserting a catheter assembly into a patient's body.

[0009] Figure 2 Depicting Figure 1 A top plan view of the catheter assembly, wherein the middle segment of the catheter is in a straight configuration shown in solid lines, and wherein the middle segment of the catheter is in a deflected configuration shown in dashed lines.

[0010] Figure 3 Depicting Figure 1 The end actuator of the catheter assembly and Figure 1 A perspective view of the distal portion of the catheter.

[0011] Figure 4 Depicting Figure 3 The top plan view of the end effector, wherein the first helical configuration is shown in solid lines and the second helical configuration is shown in dashed lines.

[0012] Figure 5 Depicting Figure 3 A perspective view of the electrode components of the end effector.

[0013] Figure 6 Depicting Figure 3 A cross-sectional side view of a portion of the end effector, showing Figure 5 The electrode is fixed to the body of the end effector.

[0014] Figure 7 Depicting what can be combined with Figure 3 A perspective view of an example of an alternative electrode in an end effector.

[0015] Figure 8 Depicting Figure 3 A cross-sectional side view of a portion of a variant of the end effector, showing Figure 7 The electrode is fixed to the body of the end effector. Detailed Implementation

[0016] The following description of certain examples of the invention is not intended to limit the scope of the invention. The accompanying drawings (not necessarily drawn to scale) depict selected embodiments and are not intended to limit the scope of the invention. The principles of the invention are illustrated in detail by way of example and not by way of limitation. Other examples, features, aspects, embodiments, and advantages of the invention will be apparent to those skilled in the art from the following description, which is shown by way of example, and a best mode is contemplated for carrying out the invention. It will be appreciated that the invention can have other different or equivalent aspects, all of which do not depart from the invention. Therefore, the drawings and descriptions should be considered substantially illustrative and not restrictive.

[0017] Any or more of the teachings, expressions, types, examples, etc., described herein may be combined with any or more of the other teachings, expressions, types, examples, etc., described herein. Therefore, the following teachings, expressions, types, examples, etc., should not be considered separate from each other. Various suitable ways in which the teachings herein can be combined will be apparent to those skilled in the art upon reference to the teachings herein. Such modifications and variations are intended to be included within the scope of the claims.

[0018] As used herein, the term “about” or “approximately” for any numerical value or range indicates a suitable dimensional tolerance that allows a collection of parts or components to achieve the intended purpose as described herein. More specifically, “about” or “approximately” may refer to a range of values ​​±20% of the listed values; for example, “about 90%” may refer to a range of values ​​from 71% to 99%. Furthermore, as used herein, the terms “patient,” “recipient,” “user,” and “examinee” refer to any human or animal examinee and are not intended to limit the system or method to human use, but the use of the subject matter invention in human patients represents a preferred embodiment.

[0019] I. Examples of Catheter Systems Figure 1 Examples of medical protocols and associated components for cardiac catheterization systems that can be used to provide the aforementioned EP mapping and / or cardiac ablation are shown. Specifically, Figure 1 A physician (PH) is shown holding the handle assembly (110) of the catheter assembly (100), wherein the catheter (120) of the catheter assembly (100) is... Figure 2 End effector (130) Figures 2 to 4The catheter assembly (100) is positioned within the patient (PA) to map potentials in tissue and / or ablate tissue in or near the patient's (PA) heart (H). The catheter assembly (100) is coupled to the guiding and actuating system (10) via a cable (30). The catheter assembly (100) is also coupled to a fluid source (42) via a fluid conduit (40). A set of field generators (20) is positioned below the patient (PA) and coupled to the guiding and actuating system (10) via another cable (22).

[0020] The guidance and drive system (10) of this example includes a console (12) and a display (18). The console (12) includes a first drive module (14) and a second drive module (16). The first drive module (14) is coupled to the conduit assembly (100) via a cable (30). In some variations, the first drive module (14) is operable to receive EP mapping signals obtained via electrodes of an end effector (130). The console (12) includes a processor (not shown) that processes such EP mapping signals and thereby provides EP mapping as known in the art. In some other variations, the end effector (130) does not provide EP mapping.

[0021] The first driver module (14) in this example is also operable to supply electrical energy to the electrodes (140) of the end effector (130) (as will be described in more detail below), thereby ablating tissue. In other types, the end effector (130) does not provide ablation.

[0022] The second driver module (16) is coupled to the field generator (20) via a cable (22). The second driver module (16) is operable to activate the field generator (20) to generate an alternating magnetic field around the heart (H) of the patient (PA). For example, the field generator (20) may include coils that generate the alternating magnetic field in a predetermined working volume that houses the heart (H).

[0023] The first actuator module (14) is also operable to receive position indication signals from one or more navigation sensors (not shown) in the end effector (130) and / or catheter (120). In this type, the processor of the console (12) is also operable to process the position indication signals from one or more navigation sensors to determine the position of the end effector (130) within the patient (PA). In some types, each navigation sensor includes one or more coils operable to generate signals indicating the position and orientation of the end effector (130) within the patient (PA). The coils are configured to generate electrical signals in response to the presence of an alternating electromagnetic field generated by the field generator (20). Other components and techniques that can be used to generate real-time position data associated with the end effector (130) may include wireless triangulation, acoustic tracking, optical tracking, inertial tracking, and the like. In some other variations, the end effector (130) and / or catheter (120) lack navigation sensors.

[0024] The display (18) is coupled to the processor of the console (12) and is operable to present images of the patient's anatomy. Such images may be based on a set of images obtained before or during surgery (e.g., CT or MRI scans, 3D mapping, etc.). The view of the patient's anatomy provided by the display (18) may also change dynamically based on signals from the navigation sensor assembly of the end effector (130). For example, as the end effector (130) of the catheter (120) moves within the patient (PA), corresponding positional data from one or more navigation sensors may cause the processor of the console (12) to update the view of the patient's anatomy in the display (18) in real time to depict the area of ​​the patient's anatomy around the end effector (130) as the end effector (130) moves within the patient (PA). Furthermore, the processor of the console (12) may drive the display (18) to show the location of abnormally conductive tissue sites detected via electrophysiological (EP) mapping using the end effector (130) or otherwise (e.g., using a dedicated EP mapping catheter, etc.). By way of example only, the processor of the console (12) can drive the display (18) to overlay the location of the abnormally conductive tissue site onto an image of the patient's anatomy with some other form of visual indication, such as by overlaying illuminated points, crosshairs or abnormally conductive tissue sites.

[0025] The processor of the console (12) can also drive the display (18) to overlay the current position of the end effector (130) onto an image of the patient's anatomy in a manner such as by overlaying illuminated points, crosshairs, a graphical representation of the end effector (130), or some other form of visual indication. As the physician moves the end effector (130) within the patient (PA), such overlaid visual indications can also move in real time within the image of the patient's anatomy on the display (18), thus providing the operator with real-time visual feedback on the position of the end effector (130) within the patient (PA) as it moves within the patient (PA). Therefore, the image provided by the display (18) can effectively provide video tracking of the position of the end effector (130) within the patient (PA) without the need for any optical instruments (i.e., cameras) for viewing the end effector (130). In the same view, the display (18) can simultaneously visually indicate the location of abnormally conductive tissue sites detected by EP mapping. Therefore, the physician (PH) can view the display (18) to observe the real-time positioning of the end effector (130) relative to the mapped abnormal conductive tissue sites and relative to images of adjacent anatomical structures within the patient (PA).

[0026] The fluid source (42) in this example comprises a bag containing brine or some other suitable flushing fluid. The conduit (40) includes a flexible tube further coupled to a pump (44) operable to selectively drive fluid from the fluid source (42) to the conduit assembly (100). Such flushing fluid may be discharged through an opening (not shown) in an end actuator (130). Such flushing can be provided in any suitable manner that will be apparent to those skilled in the art, referring to the teachings herein.

[0027] II. Examples of Catheter Components Figures 2 to 4 The end effector (100) is shown in more detail. In the example shown, and as described above, the catheter assembly (100) includes a handle assembly (110), a catheter (120) extending distally from the handle assembly (110), and an end effector (130) located at the distal end of the catheter (120).

[0028] The handle assembly (110) of this example includes a handle housing (112) that houses the components of a deflection control assembly, the operation of which will be described in more detail below. The deflection control assembly includes a rotary actuator (114) that can be directly manipulated by an operator by rotating the actuator (114) about an axis (116). The axis (116) is generally transverse to or perpendicular to the longitudinal axis of the handle housing (112). A deflection tension adjusting disc (118) is positioned opposite the actuator (114) along an axis (115). The deflection tension adjusting disc (118) is coupled to and indirectly engaged with the actuator (114) via various mechanisms and components, thereby allowing the operator to adjust the ease with which the actuator (114) can be rotated. When the actuator (114) is operated by rotation, its resistance can be adjusted by adjusting the dial (118). Other suitable features can be used to provide control of the deflection control components of the handle assembly (110), as will be apparent to those skilled in the art when referring to the teachings herein.

[0029] The catheter (120) of this example includes an elongated catheter body (122), a deflectable intermediate segment (124) located at the distal end of the catheter body (122), and a terminal segment (126) located at the distal end of the intermediate segment (124). An end actuator (130) is disposed at the terminal segment (126). As described above, the shank assembly (110) includes components of a deflection control assembly. The deflection control assembly is also coupled to the intermediate segment (124) of the catheter (120) via one or more draw wires, cables, straps, and / or other components. The deflection control assembly is operable to laterally deflect the catheter (120) at the intermediate segment (124) in response to rotation of the actuator (114). Figure 2 An example of such deflection is shown in the figure, wherein the intermediate segment (124) is shown in solid line as a straight line; and the intermediate segment is shown in dashed line as an example of a deflection configuration. Such controlled deflection at the intermediate segment (124) can facilitate the positioning of the end effector (130) at the target tissue region.

[0030] By way of example only, controlled deflection of the catheter (120) at the intermediate segment (124) can be provided according to at least some of the following documents: U.S. Patent 8,747,351, entitled “Catheter with multi-functional controlhandle having linear mechanism,” published June 10, 2014, the disclosure of which is incorporated herein by reference. In some other forms, the catheter assembly (100) lacks the feature that provides controlled deflection of the catheter (120) at the intermediate segment (124).

[0031] The end effector (130) of this example includes a generally straight proximal region (132) and a generally circular main region (134). The generally circular main region (134) may be formed as a flat circle or may be at least slightly helical, as described in more detail below. The end effector (130) includes a body (136) in the form of an electrically insulating tube, which may have a circular cross-sectional shape or any other suitable cross-sectional shape. By way of example only, the body (136) may include a poly(etherurethane) material (e.g., PELLETHANE thermoplastic polyurethane manufactured by Lubrizol Corporation (Wickliffle, Ohio)) and / or any other suitable material. A series of electrodes (140) are mounted on the body (136) in a longitudinally spaced arrangement along the generally circular main region (134). In this example, the generally circular main region (134) defines a generally helical form when unconstrained. In some types or scenarios, this helical form is centered along the longitudinal axis (125) of the intermediate segment (124). In some other forms or scenarios, the spiral shape is oriented at an angle relative to the longitudinal axis (125) of the intermediate segment (124).

[0032] In this example, the catheter assembly (100) is operable to provide controlled contraction in a helical form defined by a circular main region (134), thereby providing controlled variation of the radius and / or pitch of the helical form. Figure 3 An example of controlled variation in the spiral form of the circular main region (134) is shown. Specifically, Figure 4 The circular main region (134) with a coarser pitch is shown in solid lines; and the region with a finer pitch is shown in dashed lines. In some models, this control is provided via an actuator (not shown) of the shank assembly (110), which is operable to drive a spindle (138) slidably disposed within the body (136) of the end effector (130). Figure 4 The longitudinal movement of the spiral form defined by the circular main area (134) can be provided via one or more draw wires and / or via any other suitable component, by way of further example only.

[0033] In some variations, the controlled contraction in a spiral form defined by the circular main region (134) may be provided according to at least some of the teachings of the following patent: U.S. Patent 9,220,433, entitled “Catheter with Variable Arcuate Distal Section,” published December 29, 2015, the entire disclosure of which is incorporated herein by reference. In some other forms, the catheter assembly (100) lacks the feature providing controlled contraction in a spiral form defined by the circular main region (134).

[0034] Figure 5 The electrode (140) is shown in more detail. The electrode (140) of this example is generally annular or barrel-shaped. The electrode (140) comprises a conductive material, enabling it to be operated to apply electrical energy to tissue, as described above and in the various references cited herein. By way of example only, the electrode (140) may contain noble metals such as gold, platinum, ruthenium, palladium, silver, osmium, iridium, etc. Alternatively, any other suitable conductive material may be used. In some forms, the electrode (140) is also operable to pick up potentials in tissue (e.g., as part of an EP mapping process), also as described above and in the various references cited herein. The electrode (140) of this example includes an annular end portion (142), a central portion (144), and a transition portion (146). Each end portion (142) has a first inner diameter and a first outer diameter. The central portion (144) has a second inner diameter and a second outer diameter. The second inner diameter is larger than the first inner diameter. Similarly, the second outer diameter is larger than the second outer diameter. The transition portion (146) provides a substantially smooth transition from these different diameters of the end portion (142) and the center portion (144). In some types, each transition portion provides a straight, angled / conical surface transition between the center portion (144) and the corresponding end portion (142). In some other types, each transition portion (146) provides a curved or wavy surface transition between the center portion (144) and the corresponding end portion (142).

[0035] The electrode (140) in this example also includes a plurality of flushing openings (148) formed through a central portion (148). In this example, the flushing openings (148) are laterally oriented. In some types, a transition portion (146) also defines a flushing opening (148). The flushing openings (148) can be used to deliver flushing fluid outward from the electrode (140), as described above and in the various references cited herein. Such flushing fluid can prevent the electrode (140) from overheating, prevent condensation from accumulating on the electrode (140), promote the conductivity of the electrode (140), and / or provide other effects.

[0036] like Figure 6 As shown, flushing fluid can be delivered to the electrode (140) via a lumen (138) defined in the body (136) of the end effector (130). The lumen (138) is in fluid communication with the interior of the electrode (140) via one or more lateral ports (139), allowing flushing fluid to flow through the lumen (138) and into the interior of the electrode (140) via the lateral ports (139); and then out of the electrode (140) via the flushing opening (148). Although the lumen (138) is in Figure 6The lumen (138) is shown as spanning the entire inner diameter of the body (136), but this is merely a schematic diagram. The lumen (138) can actually be substantially smaller than... Figure 6 The lumen shown, and various other components or structures may be positioned within the body (136). Furthermore, some variations of the electrode (140) may lack the flushing opening (148). In some such variations, the lumen (138) is omitted.

[0037] For example Figure 6 As shown, the electrode (140) is secured to the body (136) via an adhesive material (160). By way of example only, the adhesive material (160) may comprise polyurethane and / or any other suitable material. The adhesive material (160) is applied at each end portion (142) of the electrode (140) and along adjacent areas of the body (136). When the adhesive material (160) is in a flowable form (e.g., a liquid, etc.), it can be applied to the electrode (140) and the body (136), and then the adhesive material (160) may later cure into a solid form. Figure 6 As shown, the inner diameter of each end portion (142) is larger than the outer diameter of the body (136), such that the adhesive material (160) flows into the gap (150) defined between the inner diameter of each end portion (142) and the outer diameter of the body (136).

[0038] The adhesive material (160) also covers the entire inner and outer surfaces of each end portion (142). Furthermore, the adhesive material (160) covers at least a portion of each transition portion (146). In some configurations, the adhesive material (160) covers more than 50% of the outer surface area of ​​each transition portion (146). However, the adhesive material (160) exposes the central portion (144), ensuring that the adhesive material (160) does not substantially interfere with the electrical connectivity and flushing function of the electrode (140).

[0039] In addition to providing structural fixation of the electrode (140) to the body (136), the adhesive material (160) also provides a liquid-tight seal at the end portions (142) of the electrode (140), thereby ensuring that flushing fluid delivered to the interior of the electrode (140) exits the electrode (140) only through the flushing opening (148). In this example, the adhesive material (160) extends longitudinally along a first width (W1) at each end of the electrode (140) such that the adhesive material (160) does not extend along the body (136) from the end portion (142) of one electrode (140) to the end portion (142) of another electrode (140). In some other forms, each region of the adhesive material (160) extends along the body (136) from the end portion (142) of one electrode (140) to the end portion (142) of another electrode (140), while still exposing the central portion (144) of each electrode (140).

[0040] III. Examples of Alternative Electrodes and Fixation During operation of the catheter assembly (100), the end effector (130) can bend multiple times in various different ways. For example, the end effector (130) can bend multiple times in various different ways as it traverses a tortuous passage on its way to a target site within the patient (PA). The end effector (130) can also bend multiple times in various different ways as the physician (PH) drives the end effector (130) to change the radius and / or pitch of the helical form defined by the circular main region (134), as referenced above. Figure 4 In some cases, bending of the end effector (130) can generate stress (e.g., tensile stress, compressive stress, torsional stress, etc.) at the edges between the adhesive material (160) and the body (136) and / or between the adhesive material (160) and the electrode (140). Such stress can ultimately cause the adhesive material (160) to delaminate from the body (136) and / or the electrode (140). Such delamination of the adhesive material can ultimately lead to blood entering the internal regions of the electrode (140), which can subsequently lead to the formation of coagulations within the electrode (140), which can then adversely affect the electrical connectivity and / or flushing capability of the electrode (140).

[0041] To enhance the fixation between the electrode (140) and the body (136) and / or otherwise reduce the risk of delamination of the adhesive material (160), there may be a tendency to simply use more adhesive material (160) to fix the electrode (140) to the body (136). However, this solution may have several drawbacks. For example, providing more adhesive material (160) along the body (136) can increase the stiffness of the end effector (130), which can make it more difficult to navigate the end effector (130) along tortuous channels and / or achieve the desired helical form in the circular main region (134). Providing more adhesive material (160) along the electrode (140) can reduce the electroactive surface area of ​​the electrode (140), which in turn can increase the current density of the electrode (140), which in turn can increase the risk of arc discharge, carbonization, agglomeration and / or other undesirable results.

[0042] Therefore, it may be desirable to provide an alternative fixation between the electrode (140) and the body (136) that reduces the risk of delamination while avoiding adverse effects such as increased stiffness of the end effector (130) and / or adverse effects on the electrical performance of the electrode.

[0043] Figures 6 to 7 An example of an alternative electrode (240) and an alternative fixation of the electrode (240) to the body (136) is shown, which provides the aforementioned advantages while avoiding the aforementioned disadvantages. Apart from the differences shown below, the electrode (240) of this example can also be constructed and operated like the electrode (140). Therefore, the electrode (240) can be incorporated into the end effector (130) as a replacement for the electrode (140).

[0044] The electrode (240) in this example is generally annular or barrel-shaped, such that the electrode (240) constitutes a generally cylindrical member extending from one annular end portion (242) to another annular end portion (242). The electrode (240) comprises a conductive material, enabling the electrode (240) to be operable to apply electrical energy to tissue, as described above and in the various references cited herein. By way of example only, the electrode (240) may contain noble metals such as gold, platinum, ruthenium, palladium, silver, osmium, iridium, etc. Alternatively, any other suitable conductive material may be used. In some types, the electrode (240) is also operable to pick up potential in tissue (e.g., as part of an EP mapping process), also as described above and in the various references cited herein. The electrode (240) of this example includes an annular end portion (242), a central portion (244), and a transition portion (246) arranged in a longitudinally extending group, wherein the central portion (244) is longitudinally centered between the end portion (242) and the transition portion (246). Each end portion (242) has a first inner diameter defined by an inner surface surrounding a central longitudinal axis (LA); and a first outer diameter. The central portion (244) has a second inner diameter defined by an inner surface surrounding a central longitudinal axis (LA); and a second outer diameter defined by an outer surface surrounding the central longitudinal axis (LA). The second inner diameter is larger than the first inner diameter. Similarly, the second outer diameter is larger than the second outer diameter.

[0045] By way of example only, the second inner diameter may be in the range of approximately 1.50 mm to approximately 3.50 mm; approximately 2.00 mm to approximately 3.00 mm; or more specifically, approximately 2.62 mm. Alternatively, the second inner diameter may be any other suitable size. By way of further example only, the electrode (240) may have a length (along the central longitudinal axis (LA)) in the range of approximately 1.00 mm to approximately 5.00 mm; approximately 2.00 mm to approximately 4.00 mm; or more specifically, approximately 3.00 mm. Alternatively, the electrode (240) may have any other suitable length.

[0046] The transition portion (246) provides a substantially smooth transition from these different diameters of the end portion (242) and the center portion (244). In some types, each transition portion provides a straight, angled / conical surface transition between the center portion (244) and the corresponding end portion (242). In some other types, each transition portion (246) provides a curved or wavy surface transition between the center portion (244) and the corresponding end portion (242).

[0047] The electrode (240) in this example also includes a plurality of flushing openings (248) formed through a central portion (248). In this example, the flushing openings (248) are laterally oriented. In some types, a transition portion (246) also defines the flushing openings (248). The flushing openings (248) can be used to deliver flushing fluid outward from the electrode (240), as described above and in the various references cited herein. Such flushing fluid can prevent the electrode (240) from overheating, prevent condensation from accumulating on the electrode (240), promote the conductivity of the electrode (240), and / or provide other effects.

[0048] like Figure 8 As shown, flushing fluid can be delivered to the electrode (240) via the lumen (138) and lateral port (139) of the body (136) of the end effector (130). (Refer to the above text.) Figure 6 As stated, although the lumen (138) is in Figure 8 The lumen (138) is shown as spanning the entire inner diameter of the body (136), but this is merely a schematic diagram. The lumen (138) can actually be substantially smaller than... Figure 8 The lumen shown, and various other components or structures may be positioned within the body (136). Furthermore, some variations of the electrode (240) may lack the flushing opening (248). In some such variations, the lumen (138) is omitted.

[0049] Unlike the electrode (140), the electrode (240) of this example also includes a set of laterally oriented openings (243) formed along each end portion (242). Each opening (243) is elongated and extends circumferentially along a portion of the end portion (242), such that the opening (243) forms a circumferential cut. Each set of openings (243) is equidistantly spaced from each other at an angle about a central longitudinal axis (LA) along the end portion (242). In this example, the openings (243) are formed only in the end portion (242), such that the openings (243) do not extend into the transition portion (246). In some other forms, at least a portion of one or more openings (243) extends into the adjacent transition portion (246).

[0050] By way of further example only, each opening (243) may have a width in the range of approximately 0.05 mm to approximately 0.35 mm; approximately 0.10 mm to approximately 0.30 mm; more specifically, it may have a width of approximately 0.20 mm (measured along a dimension parallel to the longitudinal centerline (LA)). Alternatively, each opening (243) may have any other suitable width. Furthermore, each opening (243) may have a length in the range of approximately 0.20 mm to approximately 0.60 mm; or approximately 0.30 mm to approximately 0.50 mm; or more specifically, approximately 0.40 mm (measured along a circumferential dimension extending at an angle around the central longitudinal axis (LA). Alternatively, each opening (243) may have any other suitable length.

[0051] Figure 8 The opening (243) of the electrode (240) is shown to facilitate the attachment of the electrode (240) to the body (136). The electrode (240) is attached to the body (136) via an adhesive material (260). By way of example only, the adhesive material (260) may comprise polyurethane and / or any other suitable material. The adhesive material (260) is applied at each end portion (242) of the electrode (240) and along adjacent areas of the body (136). When the adhesive material (260) is in a flowable form (e.g., a liquid, etc.), the adhesive material (260) may be applied to the electrode (240) and the body (136), and the adhesive material (260) may then be cured into a solid form later. Figure 8 As shown, the inner diameter of each end portion (242) is larger than the outer diameter of the body (136), such that the adhesive material (260) flows into the gap (250) defined between the inner diameter of each end portion (242) and the outer diameter of the body (136).

[0052] The adhesive material (260) also covers the entire inner and outer surfaces of each end portion (242). Furthermore, the adhesive material (260) flows through each opening (243), such that a portion of the adhesive material (260) effectively wraps around the entire outer region of each end portion (242) adjacent to the opening (243). In some cases, some of the adhesive material (260) may also cover a portion of the transition portion (246) adjacent to the opening (243). In some other forms, the adhesive material (260) does not cover any portion of the transition portion (246) adjacent to the opening (243). In any case, the adhesive material (260) allows the central portion (244) to be fully exposed, such that the adhesive material (260) substantially does not interfere with the electrical connectivity and flushing function of the electrode (240).

[0053] In addition to providing structural fixation of the electrode (240) to the body (136), the adhesive material (260) also provides a liquid-tight seal at the end portions (242) of the electrode (240), thereby ensuring that flushing fluid delivered into the electrode (240) exits the electrode (240) only through the flushing opening (248). In this example, the adhesive material (260) extends longitudinally along a second width (W2) at each end of the electrode (240) such that the adhesive material (260) does not extend along the body (136) from the end portion (242) of one electrode (240) to the end portion (242) of another electrode (240). In some other forms, each region of the adhesive material (260) extends along the body (136) from the end portion (242) of one electrode (240) to the end portion (242) of another electrode (240), while still exposing the central portion (244) of each electrode (240).

[0054] When comparing the attachment of electrode (240) to body (136) via adhesive material (260) with the attachment of electrode (140) to body (136) via adhesive material (160), it should be noted that the presence of opening (243) and the flow of adhesive material (260) through opening (243) provide a lower risk of delamination. This may be partly due to the tendency for the adhesive material (160, 260) to adhere better to the material of body (136) (e.g., polymer material) than to the material of electrode (140, 240) (e.g., metallic material). In the case of electrode (140), the entire interface between electrode (140) and adhesive material (160) may be susceptible to shear stress, which may frequently be encountered during normal use of end effector (130). In contrast, in the case of electrode (240), forming a ring by the flow of adhesive material through each opening (243) and adjacent areas (260) of end portion (242) significantly reduces (if not eliminates) the vulnerability to shear stress. In other words, the adhesive material (260) completely encapsulates the area of ​​the end portion (242) located between the opening (243) and the adjacent outer edge of the end portion (242). To analogize a hand's grip on the electrodes (140, 240), the fixation between the adhesive material (260) and the electrode (240) is similar to the fingers of a hand completely wrapping around a portion of the electrode (240) to fully grasp the electrode (240); however, the fixation between the adhesive material (160) and the electrode (140) is similar to the fingers of a hand simply pinching a portion of the electrode (140). The enhanced fixation between the adhesive material (260) and the electrode (240) allows the adhesive material (260) to withstand more stress and redistribute more stress to the body (136) compared to the stress applied at the interface between the adhesive material (160) and the electrode (140) in other ways.

[0055] Enhanced fixation is provided by the flow of adhesive material (260) through the opening (134). Figure 8 The arrangement shown also allows for the use of... Figure 6 The arrangement shown uses a smaller amount of adhesive material (160) than the adhesive material (260). This is demonstrated by the fact that the second width (W2) is smaller than the first width (W1). With a smaller second width (W2), more surface area of ​​the electrode (240) can be exposed by the adhesive material (260) compared to the surface area of ​​the electrode (140) exposed by the adhesive material (160). This allows the electrode (240) to provide better electrical communication with the tissue than the electrode (140). Therefore, Figure 8 The arrangement shown provides a combination of: (i) reducing the risk of delamination of the adhesive material (260) and (ii) enhancing electrical connectivity between the tissue and the electrode (240), two results that may otherwise seem contradictory to those skilled in the art.

[0056] In summary, the invention described herein provides one or more of the following advantages (among others): (i) providing a riveting effect that enhances the attachment of the electrode (240) to the body (136); (ii) partially redistributing stress on the adhesive material (260) (e.g., polyurethane, etc.) toward the opening (243) and away from the edge, and thus reducing stress on the edge of the adhesive material (260), which in turn reduces the likelihood of delamination; (iii) the opening (243) can serve as a visual guide to improve the uniformity of the edge of the adhesive material (260). Furthermore, if the use of the opening (243) reduces the likelihood of delamination, the width of the edge of the adhesive material (260) can be reduced, thereby allowing each electrode (240) to have a larger active electrode surface. Therefore, this reduces the applied current density, and thus reduces the likelihood of arc discharge and the formation of carbon on the ablated tissue.

[0057] IV. Examples of Combinations The following examples illustrate various non-exhaustive ways in which the teachings herein can be combined or applied. It should be understood that the following examples are not intended to limit the scope of any claims that may be provided at any time in this patent application or a subsequent filing thereof. No disclaimer is intended. The following examples are provided merely for illustrative purposes. It is contemplated that the various teachings herein may be arranged and applied in a variety of other ways. It is also contemplated that some variations may omit certain features mentioned in the following examples. Therefore, none of the aspects or features mentioned below should be considered definitive unless otherwise expressly indicated by the inventor or a successor with an interest in the inventor at a later date. If any claim set forth in this patent application or a subsequent filing related to this patent application includes additional features beyond those mentioned below, such additional features should not be presumed to have been added for any reason related to patentability.

[0058] Example 1 An annular electrode for pulsed field ablation, the annular electrode comprising: (a) a generally cylindrical member extending from one annular end portion to another annular end portion, wherein a central portion includes a first transition portion disposed between the central portion and the one annular portion and a second transition portion disposed between the central portion and the other annular end portion, the central portion having an inner diameter defining an inner surface about a longitudinal axis and an outer diameter defining an outer surface about the longitudinal axis, each of the annular end portions having an inner diameter smaller than the inner diameter of the central portion; and (b) a plurality of circumferential cuts disposed on one of the annular end portions or the transition portions.

[0059] Example 2 According to the annular electrode of Embodiment 1, the plurality of circumferential cuts are provided on the annular end portion.

[0060] Example 3 According to the annular electrode of Embodiment 1, the plurality of circumferential cuts are provided on the annular end portion and a portion of the transition portion.

[0061] Example 4 According to the annular electrode of Embodiment 1, each of the cuts defines a circumferential slot having a width of approximately 0.20 mm and a length of approximately 0.40 mm.

[0062] Example 5 An apparatus comprising: (a) an elongated flexible conductor having a proximal end and a distal end; (b) an end effector positioned at the distal end of a shaft, the end effector comprising: (i) a body; (ii) an electrode defining one or more laterally oriented openings; and (iii) an adhesive material securing the electrode to the body, a portion of the adhesive material being disposed in at least one of the one or more laterally oriented openings.

[0063] Example 6 According to the device of embodiment 5, the electrode includes a pair of outer portions and a central portion longitudinally inserted between the outer portions.

[0064] Example 7 According to the device of Embodiment 7, the adhesive material is positioned over at least a portion of each of the pair of outer portions.

[0065] Example 8 According to any one of embodiments 6 to 7, in the device, at least one of the one or more laterally oriented openings in which the adhesive material is disposed is positioned on one of the pair of outer portions.

[0066] Example 9 According to the device of embodiment 8, each of the pair of external portions includes a corresponding plurality of laterally oriented openings, and the one or more laterally oriented openings of the electrode include the plurality of laterally oriented openings of the external portions.

[0067] Example 10 According to any one of embodiments 6 to 9, in the device, each of the pair of external portions defines a gap with the outer surface of the body.

[0068] Example 11 According to the device of Embodiment 10, a portion of the adhesive material is disposed in the gap.

[0069] Example 12 According to any one of Embodiments 10 to 11, the gap is positioned adjacent to at least one of the one or more laterally oriented openings in which the adhesive material is disposed.

[0070] Example 13 According to any one of embodiments 6 to 12, each of the pair of outer portions has a first outer diameter, and the central portion has a second outer diameter.

[0071] Example 14 According to the device described in Embodiment 13, the second outer diameter is larger than the first outer diameter.

[0072] Example 15 According to any one of embodiments 13 to 14, the electrode further includes a pair of transition portions, each transition portion being longitudinally inserted between the central portion and a corresponding outer portion of the pair of outer portions.

[0073] Example 16 According to the device of embodiment 15, the transition portion provides a smooth transition from the first outer diameter to the second outer diameter.

[0074] Example 17 In any one of the embodiments 13 to 16, the transition portion and the central portion do not contain the adhesive material.

[0075] Example 18 The device according to any one of Embodiments 6 to 16, wherein the central portion does not contain the adhesive material.

[0076] Example 19 According to any one of embodiments 5 to 18, the one or more laterally oriented openings further include at least one flushing opening configured to discharge flushing fluid from the electrode.

[0077] Example 20 According to the device of embodiment 19, the body defines a lumen and a lateral port, the lumen and the lateral port being configured to deliver flushing fluid to the electrode for discharge via the at least one flushing opening.

[0078] Example 21 According to any one of embodiments 5 to 20, the end effector further includes a plurality of additional electrodes longitudinally spaced apart from each other along the body, each of the plurality of additional electrodes defining one or more laterally oriented openings, and the adhesive material of the end effector also securing the additional electrodes to the body, with a corresponding portion of the adhesive material disposed in at least one of the one or more laterally oriented openings of the corresponding additional electrode.

[0079] Example 22 The device according to embodiment 21 further includes an actuator operable to drive the body between a first helical configuration and a second helical configuration.

[0080] Example 23 The device according to any one of embodiments 5 to 22 further includes a handle assembly, the shaft extending distally from the handle assembly.

[0081] Example 24 The device according to any one of embodiments 5 to 23, wherein the shaft includes a steerable segment, and the device further includes an actuator operable to drive lateral deflection of the steerable segment of the shaft.

[0082] Example 25 According to any one of embodiments 5 to 24, the electrode is operable to apply electrical energy to tissue.

[0083] Example 26 In any one of the devices according to Examples 5 to 25, the adhesive material comprises polyurethane.

[0084] Example 27 The device according to any one of Examples 5 to 26, wherein the body comprises poly(etherurethane).

[0085] Example 28 The electrode of the device according to any one of embodiments 5 to 27 comprises a noble metal.

[0086] Example 29 An apparatus comprising: (a) an elongated flexible conductor having a proximal end and a distal end; and (b) an end effector positioned at the distal end of a shaft, the end effector comprising: (i) a body; (ii) a plurality of electrodes longitudinally spaced apart from each other along the body, each of the plurality of electrodes comprising: (A) a first outer portion; (B) a second outer portion; (C) a central portion longitudinally inserted between the outer portions; (D) a first set of laterally oriented openings formed through the first outer portion; and (E) a second set of laterally oriented openings formed through the second outer portion; and (iii) a plurality of discrete regions of an adhesive material securing the plurality of electrodes to the body, at least some of the discrete regions of the adhesive material being disposed in the first set of laterally oriented openings, and at least some of the discrete regions of the adhesive material being disposed in the second set of laterally oriented openings.

[0087] Example 30 A method comprising: coaxially positioning an electrode around an elongated body, the electrode having a pair of longitudinally opposed outer portions, each of the pair of longitudinally opposed outer portions defining an inner diameter, the elongated body defining an outer diameter, the inner diameter being larger than the outer diameter, such that each of the pair of longitudinally opposed outer portions defines a corresponding gap with the elongated body, each of the pair of longitudinally opposed outer portions further defining a corresponding plurality of laterally oriented openings; allowing an adhesive material to flow into the plurality of laterally oriented openings and into the gaps; and allowing the adhesive material to cure, thereby securing the electrode to the elongated body.

[0088] V. Miscellaneous Any of the devices described herein may be cleaned and sterilized before and / or after the procedure. In one sterilization technique, the device is placed in a closed and sealed container such as a plastic bag or a TYVEK bag. The container and device may then be placed in a radiation field capable of penetrating the container, such as gamma radiation, X-rays, or high-energy electrons. The radiation kills bacteria on the device and in the container. The sterilized device may then be stored in a sterile container for later use. Any other techniques known in the art may also be used to sterilize the device, including but not limited to beta or gamma radiation, ethylene oxide, hydrogen peroxide, peracetic acid, and gas-phase sterilization (with or without gaseous plasma or vapor).

[0089] It should be understood that any of the examples described herein may also include various other features in addition to those described above or as alternatives thereto. By way of example only, any of the examples described herein may also include one or more features disclosed in any of the various references incorporated herein by reference.

[0090] It should be understood that any or more of the teachings, expressions, embodiments, examples, etc., described herein can be combined with any or more of the other teachings, expressions, embodiments, examples, etc., described herein. Therefore, the aforementioned teachings, expressions, embodiments, examples, etc., should not be considered in isolation from each other. Various suitable ways in which the teachings herein can be combined will be apparent to those skilled in the art upon reference to the teachings herein. Such modifications and variations are intended to be included within the scope of the claims.

[0091] It should be understood that any patent, patent publication, or other public material allegedly incorporated herein by reference, whether in whole or in part, is incorporated only to the extent that the incorporated material does not conflict with the existing definitions, statements, or other public materials listed in this disclosure. Therefore, and to the extent necessary, the disclosures expressly listed herein replace any conflicting material incorporated herein by reference. Any material, or part thereof, allegedly incorporated herein by reference but conflicting with the existing definitions, statements, or other public materials listed herein, will be incorporated only to the extent that the incorporated material does not conflict with the existing public materials.

[0092] While various embodiments of the invention have been shown and described, further improvements to the methods and systems described herein can be achieved by suitable modifications made by those skilled in the art without departing from the scope of the invention. Several such possible modifications have been mentioned, and other modifications will be apparent to those skilled in the art. For example, the examples, types, geometries, materials, dimensions, ratios, steps, etc., discussed above are illustrative and not essential. Therefore, the scope of the invention should be considered in accordance with the following claims and should be understood as not being limited to the details of the structures and operations shown and described in the specification and drawings.

Claims

1. A ring electrode for pulsed field ablation, the ring electrode comprising: (a) A generally cylindrical member extending from one annular end portion to another annular end portion, wherein a central portion includes a first transition portion disposed between the central portion and the one annular portion and a second transition portion disposed between the central portion and the other annular end portion, the central portion including an inner diameter defining an inner surface about the longitudinal axis and an outer diameter defining an outer surface about the longitudinal axis, each of the annular end portions including an inner diameter smaller than the inner diameter of the central portion; as well as (b) A plurality of circumferential cuts, said plurality of circumferential cuts being disposed on one of the annular end portion or the transition portion.

2. The annular electrode according to claim 1, wherein the plurality of circumferential cuts are provided on the annular end portion.

3. The annular electrode according to claim 1, wherein the plurality of circumferential cuts are provided on the annular end portion and a portion of the transition portion.

4. The annular electrode of claim 1, wherein each of the cuts defines a circumferential slot having a width of approximately 0.20 mm and a length of approximately 0.40 mm.

5. An apparatus, said apparatus comprising: (a) An elongated flexible shaft having a proximal end and a distal end; as well as (b) An end effector, the end effector being positioned at the distal end of the shaft, the end effector comprising: (i) Main body, (ii) An electrode defining one or more laterally oriented openings, the electrode comprising a pair of outer portions and a central portion longitudinally inserted between the outer portions, the adhesive material positioned over at least a portion of each of the pair of outer portions, and at least one of the one or more laterally oriented openings in which the adhesive material is disposed is positioned on one of the outer portions of the pair of outer portions. (iii) An adhesive material that secures the electrode to the body, a portion of which is disposed in at least one of the one or more laterally oriented openings.

6. The device of claim 5, wherein each of the pair of external portions includes a corresponding plurality of laterally oriented openings, and the one or more laterally oriented openings of the electrode include the plurality of laterally oriented openings of the external portions.

7. The device of claim 5, wherein each of the pair of external portions defines a gap with the outer surface of the body, and a portion of the adhesive material is disposed in the gap.

8. The device of claim 6, wherein the gap is positioned adjacent to at least one of the one or more laterally oriented openings in which the adhesive material is disposed.

9. The device according to claim 5, wherein each of the pair of outer portions has a first outer diameter and the central portion has a second outer diameter.

10. The device according to claim 9, wherein the second outer diameter is larger than the first outer diameter.

11. The device of claim 9, wherein the electrode further comprises a pair of transition portions, each transition portion being longitudinally inserted between the central portion and a corresponding outer portion of the pair of outer portions.

12. The device of claim 11, wherein the transition portion provides a smooth transition from the first outer diameter to the second outer diameter.

13. The device according to claim 9, wherein the transition portion and the central portion do not contain the adhesive material.

14. The device according to claim 5, wherein the central portion does not contain the adhesive material.

15. The device of claim 5, wherein the one or more laterally oriented openings further comprises at least one flushing opening configured to discharge flushing fluid from the electrode.

16. The device of claim 15, wherein the body defines a lumen and a lateral port, the lumen and the lateral port being configured to deliver flushing fluid to the electrode for discharge via the at least one flushing opening.

17. The device of claim 5, wherein the end effector further comprises a plurality of additional electrodes longitudinally spaced apart from each other along the body, each of the plurality of additional electrodes defining one or more laterally oriented openings, the adhesive material of the end effector further securing the additional electrodes to the body, a corresponding portion of the adhesive material being disposed in at least one of the one or more laterally oriented openings of the corresponding additional electrode.

18. The device of claim 17, further comprising an actuator operable to drive the body between a first helical configuration and a second helical configuration.

19. The device according to claim 5, wherein the adhesive material comprises polyurethane, the body comprises poly(etherurethane), and the electrode comprises a noble metal.

20. An apparatus, the apparatus comprising: (a) An elongated flexible shaft having a proximal end and a distal end; as well as (b) An end effector, the end effector being positioned at the distal end of the shaft, the end effector comprising: (i) Main body, (ii) A plurality of electrodes, the plurality of electrodes being longitudinally spaced apart from each other along the body, each of the plurality of electrodes comprising: (A) First outer part (B) The second outer part, (C) A central portion, which is longitudinally inserted between the outer portions. (D) A first set of laterally oriented openings, the first set of laterally oriented openings being formed through the first outer portion, and (E) A second set of laterally oriented openings, the second set of laterally oriented openings being formed through the second outer portion, and (iii) A plurality of discrete regions of an adhesive material, wherein the plurality of discrete regions of the adhesive material fix the plurality of electrodes to the body, wherein at least some of the discrete regions of the adhesive material are disposed in a first set of laterally oriented openings, and wherein at least some of the discrete regions of the adhesive material are disposed in a second set of laterally oriented openings.

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