WO2024258395A1

WO2024258395A1 - Assemblies and methods for variable-size fistula creation

Info

Publication number: WO2024258395A1
Application number: PCT/US2023/025060
Authority: WO
Inventors: Andrzej J. Chanduszko; Kristin N. ROMINGER; Breanna SIMPSON
Original assignee: TVA Medical Inc
Current assignee: TVA Medical Inc
Priority date: 2023-06-12
Filing date: 2023-06-12
Publication date: 2024-12-19
Anticipated expiration: 2025-12-12

Abstract

An assembly for forming a fistula includes a catheter defining a lumen and an opening, an electrode moveably positioned within the lumen of the catheter, and an actuator coupled to the electrode. The actuator is operable to move the electrode relative to the opening, wherein actuation by the actuator is configured to simultaneously energize the electrode and move the electrode relative to the opening.

Description

ASSEMBLIES AND METHODS FOR VARIABLE-SIZE FISTULA CREATION

TECHNICAL FIELD

[0001] The present disclosure relates to fistula creation assemblies and methods, and more specifically, to a fistula creation assemblies and methods providing adjustable length fistula creation.

BACKGROUND

[0002] Endovascular treatments of a blood vessel may include fistula formation. A fistula is generally a passageway formed between two internal organs (e.g., blood vessels or other bodily organs). Forming a fistula between two blood vessels can have one or more beneficial functions. For example, the formation of a fistula between an artery and a vein may provide access to the vasculature for hemodialysis patients. Specifically, forming a fistula between an artery and a vein allows blood to flow quickly between the vessels while bypassing the capillaries. However, devices used for creation of a fistula may provide standardized sizes or only a single size which may not be ideal for a particular application or surgery.

SUMMARY

[0003] As noted above, one challenging aspect of forming a fistula (endovascular treatment) between blood vessels, though other body vessels are contemplated and possible, is creating a fistula of an adjustable size based on the needs of the subject using a single device. Embodiments of the present disclosure are directed to assemblies and methods for fistula formation that provide for user- selectable size of fistula formation as will be described in more detail below.

[0004] In one embodiment, an assembly for forming a fistula includes a catheter defining a lumen and an opening, an electrode moveably positioned within the lumen of the catheter, and an actuator coupled to the electrode and operable to move the electrode relative to the opening. Actuation by the actuator is configured to simultaneously energize the electrode and move the electrode relative to the opening.

[0005] In another embodiment, a method for forming a fistula includes positioning a catheter defining a lumen and an opening within a vessel and simultaneously activing and moving an electrode with an actuator to form a fistula in the vessel through the opening. [0006] In yet another embodiment, a fistula creation assembly includes a catheter defining a lumen and a notch formed with a sidewall of the catheter. A spring-biased electrode is moveably positioned within the lumen of the catheter. An actuator is coupled to the electrode and operable to move the spring-biased electrode relative to the opening, wherein actuation by the actuator is configured to simultaneously energize the spring-biased electrode and move the electrode relative to the opening.

[0007] These and additional features provided by the embodiments described herein will be more fully understood in view of the following detailed description, in conjunction with the drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

[0008] The embodiments set forth in the drawings are illustrative and exemplary in nature and not intended to limit the subject matter defined by the claims. The following detailed description of the illustrative embodiments can be understood when read in conjunction with the following drawings, where like structure is indicated with like reference numerals and in which:

[0009] FIG. 1 schematically depicts a side view of a fistula creation assembly with a moveable electrode, according to one or more embodiments shown and described herein;

[0010] FIG. 2A schematically depicts a tip of an electrode, according to one or more embodiments shown and described herein;

[0011] FIG. 2B schematically depicts a tip of an electrode, according to one or more embodiments shown and described herein;

[0012] FIG. 2C schematically depicts a tip of an electrode, according to one or more embodiments shown and described herein;

[0013] FIG. 2D schematically depicts an electrode, according to one or more embodiments shown and described herein;

[0014] FIG. 2E schematically depicts a tip of an electrode, according to one or more embodiments shown and described herein;

[0015] FIG. 3 schematically depicts a side view of a fistula creation device with a moveable electrode in a tucked position, according to one or more embodiments shown and described herein; [0016] FIG. 4 schematically depicts a fistula creation assembly with a remote motor activation device, according to one or more embodiments shown and described herein;

[0017] FIG. 5 schematically depicts a side view of a fistula creation assembly with a moveable electrode and a manual rotary thumbwheel, according to one or more embodiments shown and described herein;

[0018] FIG. 6 schematically depicts a fistula creation assembly with a moveable electrode and a control module, according to one or more embodiments shown and described herein;

[0019] FIG. 7 schematically depicts a side view of a fistula creation device with a moveable electrode having a gear assembly to move the electrode, according to one or more embodiments shown and described herein;

[0020] FIG. 8 depicts a flow chart illustrating a method for creating a fistula, according to one or more embodiments shown and described herein;

[0021] FIG. 9A schematically depicts a fistula creation assembly having an electrode in a tucked position, the assembly being positioned within a vessel adjacent another vessel, and a mating catheter aligned with the fistula creation device positioned within the adjacent vessel, according to one or more embodiments shown and described herein;

[0022] FIG. 9B schematically depicts an electrode of the fistula creation assembly positioned in a cutting position according to one or more embodiments shown and described herein;

[0023] FIG. 9C schematically depicts an electrode of the fistula creation assembly ablating tissue of the two vessels according to one or more embodiments shown and described herein; and

[0024] FIG. 9D schematically depicts a fistula formed between vessels of FIG. 8A, according to one or more embodiments shown and described herein.

DETAILED DESCRIPTION

[0025] Embodiments described herein are directed to assemblies and methods for forming a fistula. For example, a catheter may be placed in at least one of two adjacent blood vessels to form a fistula therebetween with the catheter. Specifically, embodiments described herein include a catheter including a lumen and an opening. An electrode is moveably positioned within the catheter. The electrode may be coupled to an actuator. As will be described in greater detail herein the actuator is operable to simultaneously activate and move the electrode relative to the opening. As will be described in greater detail, moving the electrode across the opening allows the electrode to perform a cutting or ablation operation to form a fistula. Furthermore, the actuator may allow for selective size variability when creating fistula. For example, a user of the device may move the electrode a desired amount across the opening to select the size of the fistula. Moreover, simultaneous activation and movement ensures cutting actions are started and stopped as desired, thereby leading to improved fistula creation control. These and additional features and benefits will be described in greater detail herein.

[0026] The terms D coupled, 0 D fixed, 0 D attached to,D and the like refer to both direct coupling, fixing, or attaching, as well as indirect coupling, fixing, or attaching through one or more intermediate components or features, unless otherwise specified herein.

[0027] The singular forms 0 aO , D an , and 0 theO include plural references unless the context clearly dictates otherwise.

[0028] The term D at least one ofl in the context of, e.g., D at least one of A, B, and CD refers only A, only B, only C, or any combination of A, B, and C.

[0029] As used in this application, stating that any part is in any way on (e.g., positioned on, located on, disposed on, or formed on, etc.) another part, indicates that the referenced part is either in contact with the other part, or that the referenced part is above the other part with one or more intermediate part(s) located therebetween.

[0030] As used herein, connection references (e.g., attached, coupled, connected, and joined) may include intermediate members between the elements referenced by the connection reference and/or relative movement between those elements unless otherwise indicated. As such, connection references do not necessarily infer that two elements are directly connected and/or in fixed relation to each other. As used herein, stating that any part is in U contactD with another part is defined to mean that there is no intermediate part between the two parts.

[0031] Unless specifically stated otherwise, descriptors such as D first,D D second, D D third, D etc., are used herein without imputing or otherwise indicating any meaning of priority, physical order, arrangement in a list, and/or ordering in any way, but are merely used as labels and/or arbitrary names to distinguish elements for ease of understanding the disclosed examples. In some examples, the descriptor 0 first! may be used to refer to an element in the detailed description, while the same element may be referred to in a claim with a different descriptor such as 0 second! or D third.! In such instances, it should be understood that such descriptors are used merely for identifying those elements distinctly that might, for example, otherwise share a same name.

[0032] Approximating language, as used herein throughout the specification and claims, is applied to modify any quantitative representation that could permissibly vary without resulting in a change in the basic function to which it is related. Accordingly, a value modified by a term or terms, such as D about! , D approximately! , and D substantially! , are not to be limited to the precise value specified. In at least some instances, the approximating language may correspond to the precision of an instrument for measuring the value, or the precision of the methods or machines for constructing or manufacturing the components and/or systems. For example, the approximating language may refer to being within a ten percent margin.

[0033] Here and throughout the specification and claims, range limitations are combined and interchanged, such ranges are identified and include all the sub-ranges contained therein unless context or language indicates otherwise. For example, all ranges disclosed herein are inclusive of the endpoints, and the endpoints are independently combinable with each other.

[0034] Referring now to FIG. 1, an assembly 10 for forming a fistula, is schematically depicted. The assembly 10 may include a first catheter 100, an electrode 134, and an actuator 138. The assembly 10 may include a greater or fewer number of components without departing from the scope of the present disclosure. As will be described in greater detail herein, the assembly 10 may form part of a multi-catheter system for forming a fistula.

[0035] The first catheter 100 may generally include a catheter body 102, a treatment portion 130, and an outer surface 131. It is noted that the first catheter 100 may include a greater or fewer number of components without departing from the scope of the present disclosure. The catheter body 102 may be sized to be advanced through a blood vessel and may include a distal tip 110 that may be shaped and/or sized to aid in advancement of the first catheter 100 through a blood vessel. For example, the distal tip 1 10 may be pointed, tapered, and/or atraumatic for advancement through a blood vessel. The distal tip 110 may be made of silicone, rubber, or any other suitable material. The catheter body 102 may have any cross-sectional shape and any diameter suitable for intravascular use. The first catheter 100, such as the catheter body 102, may define a lumen 106. For instance, the lumen 106 may extend at least partially longitudinally through the catheter body 102. The catheter body 102 may be formed of any material or combination of materials able to be traversed through a vasculature of a body. For example, the catheter body 102 may include pebax, nylon, polyurethane, polyethylene terephthalate (PET), thermoplastic elastomers, PEEK, etc.

[0036] As noted above, the first catheter 100 may have a treatment portion 130 for endovascular treatment of a blood vessel. In embodiments, the treatment portion 130 may be defined by an opening 132. The opening 132 may be a notch formed in the outer surface 131 of the catheter body 102 such as through a side wall of the first catheter 100 and may communicate with the lumen 106. The opening 132 or notch includes a notch distal end 120 and a notch proximal end 122.

[0037] In embodiments, the electrode 134 is moveably positioned within the lumen 106. For example, the electrode 134 is selectively moveable relative to the opening 132, such as across the opening 132, to allow for selective size fistula formation. In embodiments, the electrode 134 may have an exposed ablation surface or portion. In particular, the electrode 134 may have a biased portion 135 which may be configured to protrude through the opening 132 as the electrode is moved relative to the opening 132. In embodiments, electrode 134 may include a lead wire 133 or ribbon coupled to the biased portion 135. In embodiments, the lead wire 133 may be a tungsten alloy, a shape-memory material (e.g., Nitinol), or other metals (e.g. stainless steel, etc.) and may be naturally biased to curve out of the opening 132 to allow the biased portion 135 of the electrode 134 to extend out of the opening 132 to perform a cutting or ablation operation.

[0038] Referring now to FIGS. 2A-2E, the biased portion 135 of the electrode 134 may take any form suitable for assisting in forming a fistula. The various sizes and shapes of the biased portion 135 of the electrode 134 may have varying energy densities which may allow for the operator to select the preferred energy density for the given application. The various sizes and shapes of the biased portion 135 of the electrode 134 may also allow for the creation of different sizes and shapes of fistulas. For example, in FIG. 2A, the biased portion 135 of the electrode 134 is shown as a triangular prism. The triangular prism may have a cross-sectional shape of any type of triangle, including but not limited to an equilateral triangle, an isosceles triangle, a right triangle, or any other suitable type of triangle. In FIG. 2B, the biased portion 135 of the electrode 134 is shown as a cylinder. The cylinder may be oriented in any suitable orientation, including but not limited to the flat ends of the cylinder being perpendicular to the catheter body 102 (not shown), the flat ends of the cylinder being parallel to the catheter body 102 (not shown), or any other suitable orientation. In FIG. 2C, the electrode 134 is shown as a spatula. The spatula may be a largely rectangular prism and or may have a curved surface oriented towards the distal tip 110 (not shown). In FIG. 2D, the biased portion 135 of the electrode 134 is shown as a leaf spring. For example, the biased portion 135 may be at an apex of a curvature of the leaf spring and may not be positioned at a distal end of the leaf spring as in other embodiments shown herein. In FIG. 2E, the biased portion 135 of the electrode 134 is shown as a sphere. It should be understood that the different shapes of the biased portion 135 of the electrode 134 are not limited to the shapes shown and described herein, and the biased portion 135 of the electrode 134 may be any suitable shape.

[0039] The size and shape of the electrode 134 may be varied based on factors including tissue thickness and density, as well as desired fistula size, shape, and location. It is noted that the electrode 134 may include different cutting/ablation devices such as, but not limited to, an electrocautery mechanism, radiofrequency or DC based mechanisms, laser ablation devices, etc.

[0040] The electrode 134 may be movable between a radially retracted configuration, in which the electrode 134 is retained within the first catheter 100, and a protruding configuration, in which the electrode 134, such as the biased portion 135 projects beyond the outer surface 131 of the catheter body 102, as will be described herein. For example, FIG. 1 schematically depicts the electrode 134, particularly the biased portion 135, protruding through the opening 132.

[0041] Referring now to FIG. 3 the electrode 134 is illustrated as positioned within the radially retracted configuration. For example, the electrode 134 may be fully positioned within the lumen 106. For example, the electrode 134 may be positioned distal to the opening 132 and tucked against an inner surface 104 of the first catheter 100 between the distal tip 110 and the opening 132. While the electrode 134 is in the tucked position, the first catheter 100 can be advanced through a blood vessel without the electrode 134 contacting the blood vessel, or otherwise causing unwanted interference as the first catheter 100 is traversed through a vessel. In some embodiments, in the radially retracted configuration, the electrode 134 may be positioned proximal to the opening 132 within the lumen 106.

[0042] As illustrated in FIGS. 1 and 3, the electrode 134 may be operatively coupled to a power source 124. For example, the electrode 134 may be coupled to a power source 124 via a conductive wire and/or a pulling line 142 and/or one or more additionally wires or conductors. The power source 124 may be an AC or DC current source or outlet, generator, such as a RF generator, battery, or the like. The power source 124 may be housed, such as within a hand piece 136 of the catheter or may be separate therefrom. In some embodiments, the conductive wire may be coupled to or form part of the pulling line 142. For example, the pulling line 142 may be an electrically conductive material which is also capable of moving the electrode 134 within the first catheter 100 relative to the opening 132. As a non-limiting example, the pulling line 142 may be tungsten alloy, copper, aluminum, Nitinol, stainless steel, or any other suitable material. When the assembly 10 is activated, current may be supplied to and/or carried from tissue and fluid via the ablation surface to facilitate ablation or vaporization of tissue to form a fistula.

[0043] Various portions of the electrode 134, lead wire 141, and/or pulling line 142 may be insulated such as via an insulative coating or jacket (e.g., ceramic, rubber, plastic, or any suitable insulator) to prevent unwanted electrical conduction at portions proximal to the biased portion 135, for example. In some embodiments, the first catheter 100 may comprise one or more heat insulting materials (not shown) which may shield or otherwise protect the first catheter 100 and its components from heat generated by the electrode 134 during use. For example, one or more portions of the opening 132 may have one or more heat insulating portions which may include ceramic, porcelain, fiberglass, etc.

[0044] In embodiments, the first catheter 100 may further include a hand piece 136 such as coupled to a proximal end 101 of the first catheter 100. The hand piece 136 may be shaped and sized to allow an operator to grasp the hand piece 136 and manipulate the first catheter 100. As a nonlimiting example, the hand piece 136 may be a cylinder, but it is contemplated that the hand piece 136 may be any other suitable shape, such as an ergonomic shape to accommodate a hand of an operator. The hand piece 136 further may be made of any material, including but not limited to plastic, metal, or the like. The hand piece 136 further may have a high-grip material placed on an outer surface 137 of the hand piece 136, including but not limited to silicone or rubber.

[0045] In embodiments, the actuator 138 may be disposed on or positioned within the hand piece 136. The actuator 138 is operatively coupled to the electrode 134 so as to be able to position the electrode 134 relative to the opening 132. For example, the actuator 138 may be coupled to the pulling line 142, so that the actuator 138 is coupled to the electrode 134 via the pulling line 142. The actuator may be a motor 152. For example, the motor 152 may displace the pulling line 142 by rotating or winding up the pulling line 142 such as around a spool or similar structure, in turn pulling the electrode 134 proximally relative to the opening. The electrode 134 may thereby be displaced between any positions between the notch proximal end 122 and the notch distal end 120.

[0046] The actuator 138 may be activated by an activation device 144, such as may be coupled to the hand piece 136, which is electrically coupled to the actuator 138. The activation device 144 may be any suitable device which can send a signal to the actuator 138, including but not limited to a button, a switch, a joystick, a capacitive touch sensor, an LCD optical momentary switch, or any other suitable device. The signal from the activation device 144 may continuously displace the pulling line 142 while the activation device 144 is depressed. In other embodiments, the activation device 144 may displace the pulling line 142 a pre-determined distance or time, such that a single activation of the activation device 144 displaces the pulling line 142 the pre- determined distance or time, a second activation of the activation device 144 displaces the pulling line 142 the pre-determined distance or time a second instance, and so on.

[0047] The activation device 144 may also be communicatively coupled to the power source 124, for example, selectively coupling the power source 124 to the electrode 134 (such as via operation of a switch). When the activation device 144 is activated, the actuator 138 displaces the pulling line 142, which in turn displaces the electrode 134, while the power source 124 simultaneously or nearly- simultaneously energizes the electrode 134, such that the electrode 134 is displaced and energized substantially simultaneously based on a single user input.

[0048] The electrode 134 may be displaced proximally or distally. In some embodiments, the electrode 134 is energized only while the electrode 134 is displaced proximally. In this embodiment, proximally correlates to the D X direction along the X-axis. In this embodiment, a second activation of the activation device 144 may displace the electrode 134 distally while the electrode 134 is deenergized. In other embodiments, the electrode 134 is energized while the electrode 134 is displaced proximally or distally. In this embodiment, a second activation of the activation device 144 may displace the electrode 134 distally while the electrode 134 remains energized. In some embodiments, there may be multiple activation devices corresponding to different directions of displacement of the electrode 134.

[0049] Referring now to FIG. 4, an assembly 10 for providing endovascular treatment of a blood vessel, such as a fistula formation, wherein the activation device 144 is separated from the hand piece 136, is schematically depicted. The assembly 10 includes a control box 150. The activation device 144 is coupled to the control box 150. The control box 150 is communicatively coupled to the actuator 138, such that when the activation device 144 is depressed or otherwise activated a signal is sent to the actuator 138 within the handle. While a wired connection between the control box 150 and the actuator 138 is shown, it should be understood that the control box 150 and the actuator 138 may be electrically coupled by any suitable method, including but not limited to wireless connections such as Bluetooth, WiFi, cellular, or other internet-based connections.

[0050] By providing the activation device 144 separately from the hand piece 136, the embodiment shown may allow for two-handed operation such that the operator may use one hand to advance the hand piece 136 and attached first catheter 100 while the operator uses a second hand to depress or otherwise activate the activation device 144. Further, the control box 150 or activation device 144 may be a foot pedal, such that the operator may use both hands to control the hand piece 136 and attached first catheter 100 while activating the activation device 144 with their foot.

[0051] Referring now to FIG. 5, an embodiment of an assembly 10 for forming a fistula is generally depicted. The assembly 10D is substantially similar to assembly 10 described in detail above. Accordingly the description above applies to the assembly 100 unless otherwise noted or apparent and will not otherwise be repeated for brevity. In the present embodiment, the assembly 10D includes an actuator 138U which is manually turned by the operator. As a non-limiting example, the actuator 138U may be a manual rotary thumbwheel 154, wherein the operator may rotate the manual rotary thumbwheel 154. As the manual rotary thumbwheel 154 is rotated, the pulling line 142 is displaced and is spooled around, for example, a spool or ratcheting mechanism attached to the manual rotary thumbwheel 154.

[0052] The assembly 10C may further include a sensor 139 for detecting the rotation of the manual rotary thumbwheel 154. The sensor 139 may be any suitable sensor for detecting rotation, including but not limited to a hall effect sensor, a rotary encoder, a thumbwheel switch, touch sensor, LCD optical momentary switch, or any other suitable sensor type. The sensor 139 may be disposed on or within the hand piece 136. The sensor 139 may be oriented so as to detect rotation of the manual rotary thumbwheel 154. In embodiments, there may be a light emitting device, a light sensor, and a triangular cutout arranged in the manual rotary thumbwheel 154, such that light is emitted through a portion of the triangular cutout and detected by the light sensor. As the manual rotary thumbwheel 154 is rotated, the triangular cutout rotates such that the triangular cutout allows a larger amount of light to pass through and be detected by the light sensor. This embodiment may be calibrated to allow the light sensor to determine rotation and position of the manual rotary thumbwheel 154.

[0053] The sensor 139 may be coupled to a control module 160, such as may be housed within the hand piece 136 or remotely therefrom. The control module 160 can be any type of computing device and includes one or more processor units 163, one or more memory units 162, and one or more user interfaces 164. The one or more processor units 163 may include any device capable of executing machine-readable instructions stored on a non-transitory computer-readable medium, such as those stored on the one or more memory units 162. Accordingly, each of the one or more processor units 163 may include a controller, an integrated circuit, a microchip, a computer, and/or any other computing device.

[0054] The one or more memory units 162 of the control module 160 are communicatively coupled to the one or more processor units 163, such as via a wired or wireless communication path. The one or more memory units 162 may be configured as volatile and/or nonvolatile memory and, as such, may include random access memory (including SRAM, DRAM, and/or other types of RAM), flash memory, secure digital (SD) memory, registers, compact discs (CD), digital versatile discs (DVD), and/or other types of non-transitory computer-readable mediums. Depending on the particular embodiment, these non-transitory computer-readable mediums may reside within the control module 160, as shown, and/or external to the control module 160. The one or more memory units 162 may be configured to store logic (i.e., machine readable instructions) that, when executed by the one or more processor units 163, allow the control module 160 to perform various functions that will be described in greater detail below. The one or more user interfaces 164 may allow a user to enter information into the control module 160. The user interface 164 may be any suitable user interface for an operator to enter a length of time and/or distance, including but not limited to a touch pad, a keyboard, a slider, touch screen display, or the like.

[0055] The control module 160 may include a memory unit 162, a processor unit 163, and a user interface 164. The control module 160 is communicatively coupled to the sensor 139 and the power source 124. The control module 160 is shown with a wired connection to the sensor 139, but it should be understood that the control module 160 may be connected to the sensor 139 by any suitable connection system, including but not limited to wireless connections such as Bluetooth, WiFi, cellular, or internet based connections.

[0056] The sensor 139 may transmit a signal to the processor unit 163. The processor unit 163 may interpret the signal and send a signal to the power source 124 to energize the electrode 134. In some embodiments, the signal to energize the electrode 134 may correspond to the duration of time the sensor 139 detects rotation of the manual rotary thumbwheel 154. In other words, the power source 124 energizes the electrode 134 for the same duration of time that the sensor 139 detects rotation of the manual rotary thumbwheel 154. In other embodiments, the signal to energize the electrode 134 may be for a set duration of time after the sensor 139 initially detects rotation of the manual rotary thumbwheel 154. The duration of time may be stored in the memory unit 162. In embodiments, the user may specify a duration of time via the user interface 164, which may be stored in the memory unit 162.

[0057] In some embodiments, an assembly according to embodiments provided herein may include both a manual rotary thumbwheel 154 and an activation device 144. For example, as the electrode 134 is displaced by the user manually rotating the manual rotary thumbwheel 154, and the electrode 134 is energized by the activation device 144 being depressed or otherwise activated and sending a signal to the power source 124 and/or the control module 160. This may allow the user to separately displace the electrode 134 and activate the electrode 134. [0058] Referring now to FIG. 6, an assembly 1000 for forming a fistula, wherein the assembly 1 Onn includes the control module 160 is schematically depicted. The assembly 1000 is substantially similar to assembly 10 and assembly 100 described in detail above. Accordingly the description above applies to the assembly IODO unless otherwise noted or apparent and will not otherwise be repeated for brevity. The control module 160 is communicatively coupled to the actuator 138, the activation device 144, and the power source 124. The control module 160 is shown with a wired connection to the actuator 138 and the activation device 144, but it should be understood that the control module 160 may be connected to the actuator 138 and the activation device 144 by any suitable connection system, including but not limited to wireless connections as noted herein.

[0059] The memory unit 162 may store a length of time and/or distance for the electrode 134 to be energized, such that when the activation device 144 is depressed or otherwise activated, the control module 160 sends a signal to the power source 124 to energize the electrode 134 for the length of time and/or distance stored in the memory unit 162. Simultaneously when the activation device 144 is depressed or otherwise activated, the control module 160 sends a signal to the actuator to displace the pulling line 142 for the length of time and/or distance stored in the memory unit 162.

[0060] In another embodiment, the operator may enter a specified length of time and/or distance in the user interface 164. For example, and as illustrated, the user interface 164 may include a slider 165 which may slide along arrow A between various lengths of time and/or distance. The user- specified length of time and/or distance is stored in the memory unit 162 of the control module 160, such that when the activation device 144 is depressed or otherwise activated, the control module 160 sends a signal to the power source 124 to energize the electrode 134 for the user- specified length of time and/or distance stored in the memory unit 162. Simultaneously when the activation device 144 is depressed or otherwise activated, the control module 160 sends a signal to the actuator 138 to displace the pulling line 142 for the user-specified length of time and/or distance stored in the memory unit 162.

[0061] Referring now to FIG. 7, an assembly 1011 II for forming a fistula, wherein the assembly 10000 includes wherein the system includes a plurality of gears is schematically depicted. The assembly 10DDD is substantially similar to assemblies 10, 10E, and 10EU as described in detail above. Accordingly the description above applies to the assembly 1 OHHH unless otherwise noted or apparent and will not otherwise be repeated for brevity. In the present embodiment, as in the embodiment illustrated in FIG. 4 or 5 above, the present the assembly !(■ includes an actuator 138 which includes a manual rotary thumbwheel 154 attached to the hand piece 136. In this embodiment, the manual rotary thumbwheel 154 may be engaged with a gear train 145 such as by the manual rotary thumbwheel 154 being mounted to the same axle as a gear of the gear train 145. For example, the gear train 145 may include a first gear 146 and a second gear 148. The first gear 146 may mesh with the second gear 148 such that a rotation of the first gear 146 causes a rotation of the second gear 148, and a rotation of the second gear 148 causes a rotation of the first gear 146. The first gear 146 may be coupled to the pulling line 142, such that as the first gear 146 rotates the pulling line 142 spools around a spool 149 attached to the first gear 146 for example. The second gear 148 is operatively coupled to the manual rotary thumbwheel 154 such that a rotation of the manual rotary thumbwheel 154 causes rotation of the second gear 148. As the second gear 148 is meshed with the first gear 146, the first gear 146 is coupled to the pulling line 142, and the pulling line 142 is coupled to the electrode 134, rotation of the manual rotary thumbwheel 154 causes a longitudinal displacement of the electrode 134. In some embodiments, the first gear 146 may be larger diameter than the second gear 148, such that an angular rotation of the second gear 148 causes a smaller angular rotation of the first gear 146. This allows for an operator using the manual rotary thumbwheel 154 to more precisely control the electrode 134 compared to an embodiment of the assembly 10 without gears. In other embodiments not shown, the first gear 146 is a smaller diameter than the second gear 148, such that an angular rotation of the second gear 148 causes a larger angular rotation of the first gear 146. This allows for an operator to more quickly displace the electrode 134 compared to an embodiment of the assembly 10 without gears. In embodiments, it is contemplated at least one of the gears may be motor driven as opposed to manually driven.

[0062] The sensor 139 may detect rotation of the gear train 145. The sensor 139 may send a signal to the control module 160. The processor unit 163 may interpret the signal and send a signal to or otherwise operate the power source 124 to energize the electrode 134. While the sensor 139 is shown oriented to detect rotation of the second gear 148, it should be understood that the sensor 139 may be oriented to detect rotation of any part of the gear train 145, such as the first gear 146. Further, the sensor 139 may be arranged to detect rotation of the actuator 138. [0063] While the gear train 145 is shown with two gears, it should be understood that the gear train 145 may have any suitable number of gears. As a non-limiting example, the assembly 10 may include a third gear placed between the first gear 146 and the second gear 148, wherein the third gear meshes with both the first gear 146 and the second gear 148. This may allow the first gear 146 and the second gear 148 to rotate in the same direction.

[0064] Referring now to FIG. 8, a flow chart illustrating a method 900 of forming a fistula is generally depicted. It is noted that the method 900 may include a greater or fewer number of steps, taken in any order, without departing from the scope of the present disclosure. It is noted that the method 900 illustrated in FIG. 8 may be best understood when reviewed in conjunction with FIGS. 9A-9D which generally illustrate alignment and treatment of a blood vessel using the first catheter 100 as described herein. It is noted that the method as described herein is applicable to any of the embodiments described above.

[0065] Still referring to FIG. 8, at block 902 the method 900 includes positioning a first catheter 100 within a first blood vessel 400 and positioning a second catheter 170 within a second blood vessel 500 as depicted in FIG. 9A. The first catheter 100 is positioned such that the treatment portion 130 of the first catheter 100 is aligned with the treatment location 402 of the first blood vessel 400. The second catheter 170 is positioned such that the treatment portion 174 is aligned with the treatment location 402.

[0066] The treatment location 402 is a location on the surface of the first blood vessel 400 where the user intends to create a fistula, for example. While the first catheter 100 is advanced through the first blood vessel 400, the electrode 134 may be in the radially retracted configuration such that the electrode 1 4 does not contact the first blood vessel 400. The first blood vessel 400 is adjacent to a second blood vessel 500. It is noted that the first blood vessel 400 and the second blood vessel 500 may be adjacent vessels such as a vein and an artery, though vein to vein and artery to artery treatments are contemplated and possible.

[0067] The second catheter 170 may be shaped and sized similarly to the first catheter 100. The second catheter 170 has a distal tip 172, a treatment portion 174, and an opening 176 or notch. The treatment portion 130 of the first catheter 100 may be aligned across from the treatment portion 174 of the second catheter 170 such that the opening 132 of the first catheter 100 is aligned with the opening 176 of the second catheter 170. In embodiments, the opening 132 of the second catheter 170 or around the opening may be electrically or thermally insulated to prevent electrical or thermal discharge to portions of the vessel adjacent to target location. The first catheter 100 and the second catheter 170 may be aligned with one another by any suitable alignment methods, including but not limited to manual alignment or magnetic alignment. For example, each catheter may include one or more magnetic elements proximal to, distal to, or along the respective treatment portions to draw the first and second catheters to one another and to coapt the first and second blood vessels therebetween, as illustrated in FIG. 9B.

[0068] Still referring to FIG. 8, at block 904 the method 900 includes simultaneously activating and moving the electrode 134. The electrode 134 may be moved with any of the structures previously described, including by manually rotating a manual rotary thumbwheel 154 or by depressing or otherwise activating the activation device 144, which may send a signal to the motor 152 which may move the electrode 134. The electrode 134 may be simultaneously activated by any of the structures previously described, including by the sensor 139 detecting the rotation of the manual rotary thumbwheel 154 and sending a signal such as to a controller to operate a power source so as to energize the electrode 134, or the activation device 144 being depressed or otherwise activated and sending a signal such as via the controller. For example as depicted in FIG. 9B and 9C, the electrode 134 is exposed from the first catheter 100, the electrode 134 ablates or cuts tissue of the first blood vessel 400 and the second blood vessel 500. The electrode 134 may enter the opening 176 of the second catheter 170 as the electrode 134 is displaced proximally. As the electrode 134 is displaced proximally, the electrode 134 ablates or cuts tissue of the first blood vessel 400 and the second blood vessel 500 to create a fistula 404 between the first blood vessel 400 and the second blood vessel 500, as generally depicted in FIG. 9D.

[0069] Still referring to FIG. 8, at block 906 the method 900 may further include simultaneously deactivating and stopping the movement of the electrode 134. The simultaneous deactivation and stopping of movement of the electrode 134 may occur as a result of a passage of a certain amount of time since the activation of the activation device 144, ceasing the activation of the activation device 144 (i.e. releasing the activation device 144 when the activation device 144 is a button), depressing the activation device 144 as second time, displacement of the electrode 134 of certain distance, ceasing the rotation of the manual rotary thumbwheel 154, or the like. Upon formation of the fistula 404 and deactivating and stopping the movement of the electrode 134, the first catheter 100 and the second catheter 170 may be withdrawn from the respective first blood vessel 400 and the second blood vessel 500. Accordingly, a user may easily stop a cutting operation once a desired length of fistula is formed, which may be determined such as via fluoroscopy, for example.

[0070] Embodiments can be described with reference to the following numerical clause:

[0071] 1. An assembly for forming a fistula, comprising: a catheter defining a lumen and an opening, an electrode moveably positioned within the lumen of the catheter, and an actuator coupled to the electrode and operable to move the electrode relative to the opening, wherein actuation by the actuator is configured to simultaneously energize the electrode and move the electrode relative to the opening.

[0072] 2. The assembly for forming a fistula of any preceding clause, further comprising a hand piece coupled to the catheter, wherein the actuator is positioned within the hand piece.

[0073] 3. The assembly for forming a fistula of any preceding clause, further comprising a pulling line extending within the lumen and coupling the actuator to the electrode.

[0074] 4. The assembly for forming a fistula of any preceding clause, wherein the actuator comprises a thumbwheel operable to rotate in a first direction to move the electrode proximally and to rotate in a second direction to move the electrode distally.

[0075] 5. The assembly for forming a fistula of any preceding clause, wherein the electrode comprises a shape selected from a triangular prism, a cylinder, a spatula, a leaf spring, or a sphere.

[0076] 6. The assembly for forming a fistula of any preceding clause, wherein: the opening is a notch formed in a sidewall of the catheter and extends a notch length from a notch distal end to a notch proximal end, and the actuator is operable to move the electrode across the notch between a first position and a second position selectable via the actuator from any position between the notch distal end and the notch proximal end.

[0077] 7. The assembly for forming a fistula of any preceding clause, wherein the actuator comprises a motor. [0078] 8. The assembly for forming a fistula of any preceding clause, wherein the actuator further comprises a control module having a processor unit and a memory unit, wherein the control module is configured to cause the actuator to retract and deliver energy to the electrode simultaneously.

[0079] 9. The assembly for forming a fistula of any preceding clause, further comprising an activation device comprising at least one of a push button, a switch, or a joystick.

[0080] 10. The assembly for forming a fistula of clause 9, wherein the activation device is mounted to the hand piece.

[0081] 11. The assembly for forming a fistula of clause 9, wherein the activation device is separated from the hand piece.

[0082] 12. The assembly for forming a fistula of any preceding clause, further comprising a plurality of gears, wherein a first gear is mechanically coupled to the actuator, a second gear is mechanically coupled to the electrode, and the first gear and the second gear are mechanically coupled to one another.

[0083] 13. The assembly for forming a fistula of any preceding clause, wherein the electrode is spring-biased and configured to protrude through the opening.

[0084] 14. The assembly for forming a fistula of any preceding clause, wherein the actuator is operable to move the electrode between a radially retracted configuration and an extended configuration, wherein the electrode protrudes through the opening in the extended configuration.

[0085] 15. A method of forming a fistula, the method comprising: positioning a catheter defining a lumen and an opening within a vessel, and simultaneously activating and moving an electrode with an actuator to form a fistula in the vessel through the opening.

[0086] 16. The method for forming a fistula of clause 15, further comprising: engaging the actuator to simultaneously activate and move the electrode, and releasing the actuator to simultaneously stop movement of the electrode and delivery of energy. [0087] 17. The method for forming a fistula of clause 15, further comprising: engaging the actuator a first time to simultaneously activate and move the electrode, and engaging the actuator a second time to simultaneously stop movement of the electrode and delivery of energy.

[0088] 18. The method for forming a fistula of clauses 15 to 17, wherein the step of activating the motor comprises one of pressing a push button, flipping a switch, or manipulating a joystick.

[0089] 19. The method for forming a fistula of clauses 15 to 18, wherein the actuator comprises a thumbwheel.

[0090] 20. A fistula creation assembly, comprising: a catheter defining a lumen and a notch formed with a sidewall of the catheter, a spring-biased electrode moveably positioned within the lumen of the catheter, and an actuator coupled to the electrode and operable to move the spring- biased electrode relative to the opening, wherein actuation by the actuator is configured to simultaneously energize the spring-biased electrode and move the electrode relative to the opening.

[0091] 21. The assembly for forming a fistula of clause 20, further comprising a hand piece coupled to the catheter, wherein the actuator is positioned within the hand piece.

[0092] 22. The assembly for forming a fistula of clauses 20 or 21, further comprising a pulling line extending within the lumen and coupling the actuator to the electrode.

[0093] 23. The assembly for forming a fistula of clauses 20 to 22, wherein the actuator comprises a thumbwheel operable to rotate in a first direction to move the electrode proximally and to rotate in a second direction to move the electrode distally.

[0094] 24. The assembly for forming a fistula of clauses 20 to 23, wherein the electrode comprises a shape selected from a triangle, a cylinder, a spatula, a leaf spring, or a sphere.

[0095] 25. The assembly for forming a fistula of clauses 20 to 24, wherein: the notch extends a notch length from a notch distal end to a notch proximal end, and the actuator is operable to move the electrode across the notch between a first position and a second position selectable via the actuator from any position between the notch distal end and the notch proximal end. [0096] 26. The assembly for forming a fistula of clauses 20 to 25, wherein the actuator comprises a motor.

[0097] 27. The assembly for forming a fistula of clauses 20 to 26, wherein the actuator further comprises a control module having a processor unit and a memory unit, wherein the control module is configured to cause the actuator to retract and deliver energy to the electrode simultaneously.

[0098] 28. The assembly for forming a fistula of clauses 20 to 27, further comprising an activation device comprising at least one of (1) a push button, (2) a switch, or (3) a joystick.

[0099] 29. The assembly for forming a fistula of clause 28, wherein the activation device is mounted to the hand piece.

[00100] 30. The assembly for forming a fistula of clause 28, wherein the activation device is separated from the hand piece.

[00101] 31. The assembly for forming a fistula of clauses 20 to 30, further comprising: a plurality of gears, wherein a first gear is mechanically coupled to the actuator, a second gear is mechanically coupled to the electrode, and the first gear and the second gear are mechanically coupled to one another.

[00102] It should now be understood that embodiments of the present disclosure are directed to assemblies and methods for forming a fistula of variable size between two blood vessels. In some embodiments, a catheter may be placed in at least one of two adjacent blood vessels to form a fistula therebetween with the catheter. Specifically, embodiments described herein include a catheter including a lumen and an opening. An electrode is moveably positioned within the catheter. The electrode may be coupled to an actuator. The actuator is operable to simultaneously activate and move the electrode relative to the opening. As will be described in greater detail, moving the electrode across the opening allows the electrode to perform a cutting or ablation operation to form a fistula. Furthermore, the actuator may allow for selective size variability within the resulting creating fistula. For example, a user of the device may move the electrode a desired amount across the opening to select the size of the fistula. Moreover, simultaneous activation and movement ensures cutting actions are started and stopped as desired, thereby leading to improved fistula creation control. [00103] It is noted that the terms "substantially" and "about" may be utilized herein to represent the inherent degree of uncertainty that may be attributed to any quantitative comparison, value, measurement, or other representation. These terms are also utilized herein to represent the degree by which a quantitative representation may vary from a stated reference without resulting in a change in the basic function of the subject matter at issue.

[00104] While particular embodiments have been illustrated and described herein, it should be understood that various other changes and modifications may be made without departing from the spirit and scope of the claimed subject matter. Moreover, although various aspects of the claimed subject matter have been described herein, such aspects need not be utilized in combination. It is therefore intended that the appended claims cover all such changes and modifications that are within the scope of the claimed subject matter.

Claims

1. An assembly for forming a fistula, comprising: a catheter defining a lumen and an opening; an electrode moveably positioned within the lumen of the catheter; and an actuator coupled to the electrode and operable to move the electrode relative to the opening, wherein actuation by the actuator is configured to simultaneously energize the electrode and move the electrode relative to the opening.

2. The assembly of claim 1, further comprising a hand piece coupled to the catheter, wherein the actuator is positioned within the hand piece.

3. The assembly of claim 2, further comprising a pulling line extending within the lumen and coupling the actuator to the electrode.

4. The assembly of claim 1 , wherein the actuator comprises a thumbwheel operable to rotate in a first direction to move the electrode proximally and to rotate in a second direction to move the electrode distally.

5. The assembly of claim 1, wherein the electrode comprises a shape selected from a triangular prism, a cylinder, a spatula, a leaf spring, or a sphere.

6. The assembly of claim 1, wherein: the opening is a notch formed in a sidewall of the catheter and extends a notch length from a notch distal end to a notch proximal end; and the actuator is operable to move the electrode across the notch between a first position and a second position selectable via the actuator from any position between the notch distal end and the notch proximal end.

7. The assembly of claim 1, wherein the actuator comprises a motor.

8. The assembly of claim 7, wherein the actuator further comprises a control module having a processor unit and a memory unit, wherein the control module is configured to cause the actuator to retract and deliver energy to the electrode simultaneously.

9. The assembly of claim 7, further comprising an activation device comprising at least one of a push button, a switch, or a joystick.

10. The assembly of claim 9, wherein the activation device is mounted to the hand piece.

11. The assembly of claim 9, wherein the activation device is separated from the hand piece.

12. The assembly of any of the previous claims, further comprising: a plurality of gears, wherein a first gear is mechanically coupled to the actuator, a second gear is mechanically coupled to the electrode, and the first gear and the second gear are mechanically coupled to one another.

13. The assembly of claim 1, wherein the electrode is spring-biased and configured to protrude through the opening.

14. The assembly of claim 1, wherein the actuator is operable to move the electrode between a radially retracted configuration and an extended configuration, and wherein the electrode protrudes through the opening in the extended configuration.

15. A method of forming a fistula, the method comprising: positioning a catheter defining a lumen and an opening within a vessel; and simultaneously activing and moving an electrode with an actuator to form a fistula in the vessel through the opening.

16. The method of claim 15, further comprising: engaging the actuator to simultaneously activate and move the electrode; and releasing the actuator to simultaneously stop movement of the electrode and delivery of energy.

17. The method of claim 15 further comprising: engaging the actuator a first time to simultaneously activate and move the electrode; and engaging the actuator a second time to simultaneously stop movement of the electrode and delivery of energy.

18. The method of claim 15, wherein the step of activating the actuator comprises one of pressing a push button, flipping a switch, or manipulating a joystick.

19. The method of claim 15, wherein the actuator comprises a thumbwheel.

20. A fistula creation assembly, comprising: a catheter defining a lumen and a notch formed with a sidewall of the catheter; a spring-biased electrode moveably positioned within the lumen of the catheter; and an actuator coupled to the electrode and operable to move the spring-biased electrode relative to an opening, wherein actuation by the actuator is configured to simultaneously energize the spring- biased electrode and move the electrode relative to the opening.

21. The assembly of claim 20, further comprising a hand piece coupled to the catheter, wherein the actuator is positioned within the hand piece.

22. The assembly of claim 21, further comprising a pulling line extending within the lumen and coupling the actuator to the electrode.

23. The assembly of claim 21, wherein the actuator comprises a thumbwheel operable to rotate in a first direction to move the electrode proximally and to rotate in a second direction to move the electrode distally.

24. The assembly of claim 20, wherein the electrode comprises a shape selected from a triangle, a cylinder, a spatula, a leaf spring, or a sphere.

25. The assembly of claim 20, wherein: the notch extends a notch length from a notch distal end to a notch proximal end; and the actuator is operable to move the electrode across the notch between a first position and a second position selectable via the actuator from any position between the notch distal end and the notch proximal end.

26. The assembly of claim 20, wherein the actuator comprises a motor.

27. The assembly of claim 20, wherein the actuator further comprises a control module having a processor unit and a memory unit, wherein the control module is configured to cause the actuator to retract and deliver energy to the electrode simultaneously.

28. The assembly of claim 20, further comprising an activation device comprising at least one of (1) a push button, (2) a switch, or (3) a joystick.

29. The assembly of claim 20, wherein the activation device is mounted to the hand piece.

30. The assembly of claim 20, wherein the activation device is separated from the hand piece.

31. The assembly of any of the previous claims, further comprising: a plurality of gears, wherein a first gear is mechanically coupled to the actuator, a second gear is mechanically coupled to the electrode, and the first gear and the second gear are mechanically coupled to one another.