WO2024263981A1

WO2024263981A1 - Systems and methods for delivering implantable medical devices using interventional approaches

Info

Publication number: WO2024263981A1
Application number: PCT/US2024/035109
Authority: WO
Inventors: Jace Valls; Anthony Pantages; Jonathan Cox
Original assignee: Shifamed Holdings, Llc
Priority date: 2023-06-21
Filing date: 2024-06-21
Publication date: 2024-12-26

Abstract

The present technology provides implantable medical devices and systems and methods for percutaneously delivering the same. In some embodiments, the present technology includes a pusher catheter assembly configured to provide pushing forces against an implantable medical device collapsed within a delivery sheath to push the device out of the sheath and deploy the device at a target anatomical location. The pusher catheter assembly can include one or more device engagement component that are designed to provide pushing forces against the device when the device is positioned within the sheath. The device engagement component can be sized and shaped to bypass one or more first components of the device positioned proximally within the sheath such that the pusher catheter assembly provides pushing forces against one or more second components of the device that are positioned distally within the sheath.

Description

SYSTEMS AND METHODS FOR DELIVERING IMPLANTABLE

MEDICAL DEVICES USING INTERVENTIONAL APPROACHES

CROSS-REFERENCE TO RELATED APPLICATION(S)

[0001] The present application claims priority to U.S. Provisional Application No. 63/509,386, filed June 21, 2023, the disclosure of which is incorporated by reference herein in its entirety.

TECHNICAL FIELD

[0002] The present technology generally relates to systems and methods for delivering and deploying implantable medical devices and, in particular, to systems and methods for delivering and deploying shunting systems for fluidly connecting a first body region and a second body region.

BACKGROUND

[0003] Implantable shunting systems are widely used to treat a variety of patient conditions by shunting fluid from a first body region/cavity to a second body region/cavity. For example, interatrial shunting systems that shunt blood from the left atrium of the heart to the right atrium of the heart have been proposed as a treatment for heart failure in general, and heart failure with preserved ejection fraction in particular. Proposed shunting systems range in complexity from simple tube shunts to more sophisticated systems having on-board electronics, adjustable lumens, and the like. Despite the advancement of shunting system technology, designing shunting systems that can be reliably and relatively non-invasively delivered and deployed across a target structure remains a challenge.

BRIEF DESCRIPTION OF THE DRAWINGS

[0004] FIG. 1 A illustrates an adjustable shunting system in a deployed configuration and configured in accordance with select embodiments of the present technology.

[0005] FIG. IB illustrates the adjustable shunting system of FIG. 1A deployed across a septal wall of a patient. [0006] FIG. 2 illustrates the adjustable shunting system of FIGS. 1A and IB collapsed in a delivery sheath for delivery to a treatment site within a patient and configured in accordance wi th select embodiments of the present technology.

[0007] FIG. 3 illustrates a pusher catheter assembly for assisting with percutaneously delivering and deploying an implantable medical device and configured in accordance with select embodiments of the present technology.

[0008] FIGS. 4A-4C illustrate a pushing element of the pusher catheter assembly of FIG. 3 and configured in accordance with select embodiments of the present technology⁷.

[0009] FIG. 5 A illustrates the adjustable shunting system of FIGS. 1A and IB and the pusher catheter assembly of FIG. 3 positioned within a delivery⁷ sheath for percutaneously implanting the adjustable shunting system within a patient.

[0010] FIGS. 5B-5E illustrate various stages of a percutaneous implant procedure for deploying the adjustable shunting system of FIGS. 1A and IB across a septal wall using the pusher catheter assembly of FIG. 3.

[0011] FIG. 5F illustrates additional features of the pusher catheter assembly of claim FIG. 3.

[0012] FIGS. 6A-6C illustrate another embodiment of a pusher catheter assembly configured in accordance with select embodiments of the present technology⁷.

[0013] FIGS. 7A-7C illustrate another embodiment of a device engagement component of a pusher catheter assembly configured in accordance with select embodiments of the present technology.

[0014] FIGS. 8A-8C illustrate an introducer system for loading an implantable medical device into a delivery sheath and configured in accordance vxi th select embodiments of the present technology.

[0015] FIGS. 9A-9E illustrate another introducer system for loading an implantable medical device into a delivery sheath and configured in accordance with select embodiments of the present technology⁷.

DETAILED DESCRIPTION

[0016] The present technology is directed to implantable medical devices and systems and methods for percutaneously delivering the same using interventional techniques. In some

0 embodiments, for example, the present technology includes a pusher catheter assembly configured to provide pushing forces against an implantable medical device collapsed within a delivery sheath to push the device out of the delivery sheath and deploy the device at a target anatomical location within a patient. The pusher catheter assembly can include one or more device engagement components designed to provide pushing forces against the device when the device is positioned within the delivery sheath. Of note, the device engagement component(s) can be sized and shaped to at least partially bypass one or more first components or portions of the device positioned proximally within the delivery sheath such that the pusher catheter assembly provides pushing forces directly against one or more second components or portions of the device that are positioned distally within the delivery sheath. As described in detail throughout this Detailed Description, this is expected to be particularly advantageous in embodiments in which a device component expected to provide substantial frictional resistance during deployment of the device is not the proximal-most positioned component of the device within the delivery sheath.

[0017] In some embodiments, the disclosed pusher catheter assemblies are configured for use with an implantable shunting system having one or more canisters and a superelastic wireframe anchor structure. When positioned within a delivery sheath, the shunting system may be arranged in an end-to-end configuration in which the canister is proximal to the anchor structure. How ever, the anchor structure may provide greater frictional resistance to deployment of the shunting system than the canister (e.g., due to it being in a collapsed configuration). Accordingly, the pusher catheter assemblies described herein can bypass the canister positioned proximal to the anchor structure to provide pushing forces directly upon the anchor structure. Without being bound by theory, this is expected to be advantageous because it may make it easier to deploy the shunting system from the delivery' sheath and/or reduce device deformation during deployment.

[0018] The terminology' used in the description presented below' is intended to be interpreted in its broadest reasonable manner, even though it is being used in conjunction with a detailed description of certain specific embodiments of the present technology. Certain terms may even be emphasized below; however, any' terminology intended to be interpreted in any restricted manner will be overtly and specifically defined as such in this Detailed Description section. Additionally, the present technology can include other embodiments that are within the scope of the examples but are not described in detail with respect to FIGS. 1 A-9E. [0019] Reference throughout this specification to “one embodiment” or “an embodiment” means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment of the present technology. Thus, the appearances of the phrases “in one embodiment” or “in an embodiment” in various places throughout this specification are not necessarily all referring to the same embodiment. Furthermore, the particular features or characteristics may be combined in any suitable manner in one or more embodiments.

[0020] As used herein, the use of relative terminology, such as “about”, “approximately”, “substantially” and the like refer to the stated value plus or minus ten percent. For example, the use of the term “about 100” refers to a range of from 90 to 110, inclusive. In instances in which the context requires otherwise and/or relative terminology is used in reference to something that does not include a numerical value, the terms are given their ordinary meaning to one skilled in the art.

[0021] The headings provided herein are for convenience only and are not to be used to interpret the scope of the claimed technology.

A. Select Embodiments of Implantable Medical Devices and Devices for Delivering the Same

[0022] FIG. 1A illustrates an adjustable shunting system 100 (“the system 100”) in a deployed configuration and configured in accordance with select embodiments of the present technology. As described in detail below, the system 100 can be configured to shunt fluid between a first body region and a second body region when implanted in a patient. For example, FIG. IB illustrates the system 100 implanted across a septal wall S of a patient to shunt blood between the left atrium and the right atrium of the patient.

[0023] Referring to FIG. 1A, the system 100 includes an anchoring or stabilizing feature or structure 110 (“the anchor structure 110”) configured to secure the system 100 to patient tissue and/or stabilize the position of the system 100 in a desired anatomic location. In the illustrated embodiment, the anchor structure 110 is a wire or filament structure (e.g., a braided or woven wire structure) having a generally annular geometry. A radially inward portion 111 of the anchor structure 110 defines a central opening or passage 113. As described in greater detail below, an actuator 116 can be coupled to the anchor structure 110 and sit at least partially within the opening 113 and/or extend from a perimeter of the radially inward portion 111. The actuator 11 can define or at least partially define a lumen 118 extending through the opening 113, as also described in greater detail below.

[0024] In the illustrated embodiment, the anchor structure 110 includes a first plurality of petals or appendages 110a and a second plurality of petals or appendages 110b. In some embodiments, the wire forming pattern of the anchor structure 1 10 results in immediately adjacent petals of the first petals 110a not being formed by an adjacent segment of the wire structure forming the anchor structure 110. Instead, the wire structure can alternate between first petals 11 Oa formed on a first side of the system 100 and second petals 11 Ob formed on the second side of the system 100 (e.g., the portion of the wire structure that forms an individual first petal 110a at a 12:00 position may cross to the other side of the anchor structure 110 to form an individual second petal 110b at a 3:00 position before crossing back to form another individual first petal 110a at a 5:00 position, and so on). The first plurality of petals 110a and the second plurality of petals 110b are separated by a gap (not shown).

[0025] When the system 100 is deployed across a tissue structure such as the septal wall S shown in FIG. IB, the system 100 is configured to receive patient tissue between the first petals 110a and the second petals 110b, e.g., in the gap. Additionally, the first plurality of petals 110a and the second plurality of petals 110b can be at least partially biased tow ard one another such that the first petals 110a and the second petals 110b at least partially squeeze patient tissue received within the gap to secure the system 100 to the septal wall S. Accordingly, when deployed across the septal wall S, the first petals 110a may reside within the right atrium, the second petals 110b may reside within the left atrium, and the gap between the first petals 110a and the second petals 110b may receive a portion of the patient's septal w all S (e g., at the fossa ovalis). The first petals 110a may be biased at least slightly toward the second petals 110b (and/or the second petals 1 10b may be biased at least slightly tow ard the first petals 110a) such that the anchor structure 110 forms a slight clamping force on the portion of the septal wall S within the gap. In some embodiments, the first petals 110a and the second petals 110b are at least partially staggered such that individual first petals 110a do not entirely overlap with individual second petals 110b. Without being bound by theory, this is expected to spread the pinching force over a larger area of the septal wall S.

[0026] The anchor structure 110 can be at least partially composed of a self-expanding material such that, after being exposed to stress and strain induced by being collapsed into a deliver}' tool (e.g., catheter, sheath, etc. as described in greater detail below' with reference to FIG. 2) for delivery, it exhibits an elastic response when being deployed at body temperature. For example, the anchor structure 110 can be composed of Nitinol that has an austenite finish temperature below body temperature. Accordingly, the anchor structure 110 can automatically deploy (e.g., self-expand without additional input or manipulation by a clinician) from a collapsed delivery⁷ configuration to an expanded deployed configuration when released from the delivery tool. In some embodiments, the self-expanding or superelastic properties of the anchor structure 110 may also enable the anchor structure 110 to resist plastic mechanical deformation once deployed, and thus can provide a generally stable anchoring mechanism for the system 100. In other embodiments, the anchor structure 110 can be composed of a material that is not selfexpanding at body temperature, and can be manually expanded by an operator after an initial deployment using tools such as catheters, sutures, balloons, and the like. Additional details regarding anchoring features suitable for use with the system 100 are described in International Patent Application Publication No. WO 2023/064479, the disclosure of which is incorporated by reference herein in its entirety⁷.

[0027] The actuator 116 extends through the opening 113 of the anchor structure 110. As shown, the actuator 116 can be formed via one or more wires or wire-like structures formed to have a plurality of projections 117 (e.g., leaflets, fingers, wings, struts, etc.). The projections 117 can be formed to define a cylindrical, conical, funnel, and/or hyperboloid shape. In some embodiments, the plurality of projections 117 are formed from a single or common wire structure. In other embodiments, individual projections 117 (or fewer than all of the plurality of projections 117) of the plurality of projections 117 can be formed by separate wire structures. The projections 117 can be covered by one or more membranes (not shown in FIGS. 1 A and IB for clarity). The one or more membranes can be fluidically impermeable, or at least partially fluidically impermeable, to blood and/or other bodily fluids. Accordingly, the actuator 116 and membrane (not shown) can together define the lumen 118 through which fluid can pass through the system 100. For example, when the system 100 is implanted across the septal wall S as shown in FIG. 1 B, blood can flow between the left atrium and the right atrium via the lumen 118.

[0028] The actuator 116 can be adjustable to change one or more therapy parameters associated with the system 100 (e.g., fluid resistance, lumen size, orifice size, flow rate, etc.) to control the therapy provided by the system 100. For example, the projections 117 can be selectively flared inwardly or outwardly to change the shape and/or size of the lumen 118. Accordingly, the actuator 116 can be transitioned through a plurality of unique positions or configurations, with each unique position or configuration providing a different fluid resistance through the lumen 118. To facilitate such movement, the actuator 116 can be composed at least in part of a shape memory material, such as Nitinol. Additional details regarding actuators generally similar to the actuator 116 are described in International Patent Application No. PCT/US23/85189 and U.S. Patent Application Publication Nos. US 2021/0085935 and US 2022/0142652, the disclosures of which are all incorporated by reference herein in their entireties.

[0029] As best shown in FIG. 1 A, the system 100 further includes a first canister 120 and a second canister 122. The canisters 120. 122 are sealed (e.g., hermetically sealed) containers that house various electronics and other components of the system 100. For example, the canisters 120, 122 can house one or more energy storage components (e.g., a primary cell battery, a rechargeable battery, a capacitor, a supercapacitor, etc.), one or more sensors or associated electronic circuitry (e.g.. pressure sensor, flow sensor, etc.), one or more data storage elements (e.g.. memory), one or more processors, one or more telemetry components, one or more microcontrollers, or the like. The canisters 120, 122 can be composed of a generally rigid material, such as titanium, steel, plastic, or the like. The canisters 120, 122 may also be covered by a biocompatible membrane composed of, for example, ePTFE or another suitable material. Although shown as having two canisters 120, 122. in other embodiments the system 100 can have fewer or more canisters, such as one, three, four, or more. In the illustrated embodiment, the first canister 120 resides on or proximate to a near or first side (e.g., a right atrium side) of the anchor structure 110, and the second canister 122 resides on or proximate to a far or second side (e.g., a left atrium side) of the anchor structure 110, although other configurations are possible.

[0030] The canisters 120, 122 can be mechanically coupled to the anchor structure 110. In the illustrated embodiment, for example, the first canister 120 is coupled to a first petal 110a of the anchor structure 110 via a first tether 121, and the second canister 122 is coupled to a second petal 110b of the anchor structure 110 via a second tether 123. More specifically, the first tether 121 couples a first end portion 120a of the first canister 120 to the anchor structure 110, and the second tether 123 couples a first end portion 122a of the second canister 122 to the anchor structure 110. In some embodiments, the system 100 may include additional tethers coupling the canisters 120, 122 to the anchor structure 110, e.g., to improve positional stability' between the canisters 120, 122 and the anchor structure 110. [0031] In some embodiments, the first tether 121 and the second tether 123 can be configured to orient the first canister 120 and the second canister 122. respectively, in desired positions relative to the anchor structure 110. For example, the first tether 121 and the second tether 123 can be composed of a shape-memory material (e.g., shape memory alloys such as Nitinol, NiTiCu, NiTiPd, AgCd, AuCd, etc., or shape memory polymers such as biopolyethylene terephthalate) that bias the canisters 120, 122 toward a desired position (e.g., toward the positions shown in FIG. 1 A). As another example, the first tether 121 and the second tether 123 can be composed of an elastic material that likewise biases or moves the canisters 120, 122 toward a desired position. In such embodiments, the first tether 121 and the second tether 123 may assist with moving the first canister 120 and the second canister 122 toward the desired position upon deployment of the system 100 from a delivery sheath. As yet another example, the first tether 121 and the second tether 123 can be composed of a rigid (or at least semi-rigid) and inflexible material, such as stainless steel. In yet another example, the first tether 121 and the second tether 123 can be one or more sutures. Accordingly, the first tether 121 and the second tether 123 can at least partially hold the canisters 120. 122 in the desired position even if deformation forces are applied against the canisters 120, 122.

[0032] The first canister 120 can also be coupled to the second canister 122. In the illustrated embodiment, for example, the first canister 120 is coupled to the second canister 122 via an electrical connector 126. The electrical connector 126 can include one or more conductive electrical wires or filaments for transmitting electrical signals (e.g., energy, data, etc.) between electrical components within the first canister 120 and electrical components within the second canister 122. As an example, energy stored in the first canister 120 can be transmitted via the electrical connector 126 to power active components stored in the second canister 122, or vice versa. As another example, a microcontroller in the first canister 120 can send instructions via the electrical connector 126 to control the operation of a sensor in the second canister 122. or vice versa. The electrical connector 126 may also include a data and/or power transmission element (e.g., an antenna) for wirelessly sending or receiving data and/or power to or from a device external to the patient. By virtue of connecting the first canister 120 and the second canister 122, and as shown in FIG. IB, the electrical connector 126 extends through the septal wall S when the system 100 is implanted across the septal wall S. Additional details regarding the electrical connector 126 are described in International Patent Application Publication No. WO 2022/272131, the disclosure of which is incorporated by reference herein in its entirety. [0033] FIG. 2 illustrates the system 100 positioned within a delivery catheter or delivery' sheath 200 (‘"the delivery sheath 200") in a "‘delivery configuration” and configured in accordance with select embodiments of the present technology. As shown, the components of the system 100 are arranged in an “end-to-end” arrangement when loaded in the delivery sheath 200. For example, the first canister 120, the anchor structure 110, and the second canister 122 are arranged in a linear, non-overlapping manner. The actuator 116 (FIGS. 1 A and IB) is omitted from FIG. 2 for clarity, but would sit generally within/proximate the anchor structure 110. As shown, the first canister 120, the anchor structure 110, and the second canister 122 do not overlap when positioned within the delivery' sheath 200. This arrangement is expected to be advantageous because it minimizes the outer diameter of the system 100 in the deliveryconfiguration, which in turn is expected to (a) reduce the size of the delivery sheath 200 needed to deliver the system 100, and (b) reduce the invasiveness of the delivery procedure. For example, the system 100 can be collapsed such that it can be delivered in a 22 French delivery sheath or smaller, a 24 French delivery sheath or smaller, a 26 French delivery sheath or smaller, a 28 French delivery sheath or smaller, a 30 French delivery sheath or smaller, etc. As a result, the system 100 may have an axial end-to-end length of between about 20mm and 80mm in the delivery configuration, compared with an axial end-to-end length of betw een about 5mm and about 20mm once deployed.

[0034] In operation, the delivery sheath 200 is advanced through the patient’s vasculature (e.g., via a femoral entry- point) toward a target structure. In the context of an atrial shunt, for example, the delivery sheath 200 is advanced through the patient’s vasculature until the distal portion of the delivery sheath 200 is positioned through a pre-formed puncture or other opening in the septal wall between the left atrium and the right atrium. With the distal portion of the delivery- sheath 200 in the left atrium, the system 100 is pushed out of the delivery- sheath 200 and/or the delivery sheath 200 is retracted relative to the system 100 such that the system is deployed across the septal wall, as shown in FIG. IB. As set forth above, the anchor structure 1 10, the first tether 121 , and/or the second tether 123 can be composed at least in part of superelastic (e.g., shape memory) material that causes the system 100 to automatically spring/deploy into the deployed configuration upon ejection from the delivery sheath 200. In other embodiments, the anchor structure 110 may need to be mechanically expanded (e.g., via balloon expansion) following ejection from the deli very' sheath 200.

[0035] Depending upon the construction of the system 100. pushing the system 100 out of the delivery sheath 200 during deployment of the system 100 may present several unique challenges. For example, when the anchor structure 110 is collapsed into the delivery' configuration shown in FIG. 2, the anchor structure 110 may exhibit a radially outward force toward its biased (i.e., deployed) configuration. As a result, a substantial amount of friction is generated between the inner surface of the delivery sheath 200 and the anchor structure 110 when the system 100 is pushed relative to the delivery sheath 200, such as during deployment of the system 100 from the delivery sheath 200. As a result of this friction, when the proximal -most component of the system 100 (i.e., the first canister 120) is pushed distally during deployment, the proximal-most component (i.e., the first canister 120) may move relative to the delivery sheath 200 but the anchor structure 110 may remain stationary relative to the delivery' sheath 200. This may cause several issues. First, the anchor structure 110 may not move distally and thus not be deployed from the delivery sheath 200. Second, the first end portion 120a of the first canister 120 may at least partially enter into the anchor structure 110, further flaring the anchor structure 110 outwardly and creating even more friction between the anchor structure 110 and the inner surface of the delivery' sheath 200. Third, movement of the first canister 120 relative to the anchor structure 110 may substantially deform (and thus potentially damage) the first tether 121 and/or the electrical connector 126 extending from the first end portion 120a of the first canister 120.

B. Select Embodiments of Pusher Catheter Assemblies for Assisting with Delivery of Implantable Medical Devices

[0036] FIG. 3 illustrates a pusher catheter assembly 300 (“the assembly 300”) configured in accordance with select embodiments of the present technology and that is expected to address some or all of the foregoing challenges associated with delivering implantable medical devices. The assembly 300 includes a handle 350, an elongate pushing catheter 302 (“the catheter 302”) extending from the handle 350, and a device engagement component or feature 310 extending from an end of the catheter 302. The assembly 300 can optionally include an outer sleeve 306 (shown in broken lines) that couples the catheter 302 to the device engagement component 310.

[0037] The handle 350 can be sized and shaped such that a user can grasp the handle 350 to control the catheter 302 and device engagement component 310 as they are advanced within vasculature of a patient. The handle 350 can also include an actuator or trigger 352 and an actuator or trigger guard 354. As described in greater detail below with reference to FIG. 5F, the actuator 352 can be used to control various functions of the assembly 300, such as to deploy a push rod (not shown) to assist with deploying an implantable medical device. [0038] The catheter 302 can include an elongated structure that is substantially rigid (e.g., generally not compressible) along its axial length but is at least partially bendable along its axial length. For example, the catheter 302 can have a laser cut or other pattern that provides axial stiffness while retaining some degree of bendability. The catheter 302 is configured to extend coaxially within another delivery catheter or delivery' sheath (e.g., the delivery sheath 200 of FIG. 2) between the device engagement component 310 and the arterial/v enous access point. Accordingly, the catheter 302 may have an outer diameter that is less than an inner diameter of a delivery sheath. For example, the catheter 302 may have an outer diameter of less than about 24 French, less than about 22 French, less than about 20 French, less than about 18 French, etc. The catheter 302 may have an axial length that is sufficient to ensure the assembly 300 can extend between an arterial/venous access point and a target deployment location. For example, the catheter 302 may have an axial length of at least 100 cm, at least 150 cm, at least 200 cm, at least 250 cm, at least 300 cm, etc. In some embodiments, the catheter 302 can be composed of a substantially rigid material or blends of materials, such as plastic, steel, stainless steel, titanium, or other metals or metal alloys.

[0039] The device engagement component 310 is positioned at a distal end of the catheter 302 and is configured to interface with, and provide pushing forces directly upon, one or more components of a system positioned within a delivery sheath. More specifically, and as described in detail below, the device engagement component 310 enables pushing forces to be directed against a component of the cathet erized system that is expected to experience the greatest amount of friction during deployment of the system from the catheter, regardless of whether such component is the “proximal-most” component in the catheter. For example, the device engagement component 310 enables pushing forces to be directly applied to the anchor structure 110 (FIGS. 1A-2) instead of, or in addition to, pushing forces being directly applied to the first canister 120 (FIGS. 1A-2).

[0040] The device engagement component 310 includes a tubular section 312 and a pusher section 314. The tubular section 312 is coupled to (e.g., extends from) the distal end portion of the catheter 302, and the pusher section 314 is coupled to (e.g., extends from) a distal end portion of the tubular section 312. In some embodiments, the device engagement component 310 can be composed of a generally rigid material or blend of materials, such as plastic, steel, stainless steel, titanium, or other metals or metal alloys. Additional details of the device engagement component 310 are described below with reference to FIGS. 4A-4C. [0041] The outer sleeve 306 can include a hollow tube that extends over a portion of the catheter 302 and at least a portion of the tubular section 312 of the device engagement component 310. The outer sleeve 306 can couple (or assist with coupling) the catheter 302 to the tubular section 312. The outer sleeve 306 can be composed of plastic, metal, or other suitable materials. In other embodiments, the outer sleeve 306 is omitted and the catheter 302 is coupled to the tubular section 312 via other mechanisms, such as via a mechanical coupling (e g., keyed or mating locks), welding, suturing, or the like.

[0042] FIGS. 4A-4C are enlarged views of the device engagement component 310 with other aspects of the assembly 300 omitted for clarity. In particular, FIG. 4A is a first isometric view of the device engagement component 310, FIG. 4B is a second isometric view of the device engagement component 310 rotated about 90 degrees clockwise relative to the first isometric view of FIG. 4A, and FIG. 4C is an isometric view of the device engagement component 310 during a stage of manufacture.

[0043] Referring to FIGS. 4A and 4B collectively, the tubular section 312 can comprise a hollow hypotube 416 extending between a first end region 416a and a second end region 416b. The hypotube 416 can include a laser cut or otherwise formed relief pattern that enables the hypotube 416 to bend in, for example, two directions, but prevents (or at least substantially prevents) the hypotube 416 from bending in other directions. This is expected to increase the stiffness of the hypotube 416 in the axial distance (e.g.. increase the rigidity of the hypotube along its axial length and decrease the axial compressibility of the hypotube 416). This configuration is expected to be advantageous because it increases the efficiency with which pushing forces are transmitted from the catheter 302 to the pusher section 314 of the device engagement component 310 when the assembly 300 is used to push an implantable medical device out of a delivery sheath. The first end region 416a of the hypotube 416 can be translationally and rotatably locked relative to the catheter 302 (FIG. 3) to further facilitate efficient transfer of pushing forces therebetween.

[0044] The pusher section 314 includes a plurality of splines or appendages 418 that extend distally from the second end region 416b of the hypotube 416. In the illustrated embodiments, the pusher section 314 includes six splines 418; although in other embodiments, the pusher section 314 can include fewer or more splines 418, such as two, three, four, five, seven, eight, or more. Each spline 418 includes an elongated and generally linear structure. Although shown as having a generally flat profile, the splines 418 can have other suitable configurations. However, having a generally flat profile is expected to be advantageous because it may reduce a cross-sectional area occupied by the splines 418 when the device engagement component 310 is positioned within a catheter, as described in greater detail with reference to FIG. 5 A.

[0045] The splines 418 are arranged in a generally annular configuration to form a cylindrical or conical shaped opening 419 (FIG. 4B) between radially inner surfaces of the splines 418. As described in greater detail below with reference to FIG. 5A, the opening 419 can receive one or more components of an implantable medical device when the device is positioned within a delivery sheath for percutaneous delivery. In some embodiments, the splines 418 may flare slightly outwardly relative to the hypotube 416 to assist w ith receiving one or more device components within the opening 419. For example, a longitudinal axis extending along an axial length of an individual spline 418 may form a non-zero angle with a longitudinal axis extending along an axial length of the hypotube 416. The non-zero angle may be between about 1 degree and about 30 degrees, or between about 1 degree and about 20 degrees, or between about 1 degree and about 10 degrees, or between about 1 degree and about 5 degrees. In some embodiments, the splines 418 may be able to flex radially inwardly and/or radially outwardly relative to the hypotube 416 such that the angle therebetween can change.

[0046] Distal ends 420 of the splines 418 can be configured to transmit pushing forces to a component of an implantable medical device when the device is positioned in a delivery sheath. For example, each distal end 420 can include a pushing surface 422 that extends at about a 90- degree angle from the splines 418 at a first bend region 421. The 90-degree bend in the splines 418 at the first bend regions 421 increases a contact area between the splines 418 and a device component during a delivery procedure at the pushing surface 422. This is expected to more efficiently transmit pushing forces to the device component. For additional stability, the splines 418 may have second bend regions 423 that cause the spline 418 to bend back tow ard its radially inner surface.

[0047] FIG. 4C illustrates the device engagement component 310 before the pushing surface 422 has been formed. For example, the device engagement component 310 can be lasercut from a tube in the configuration shown in FIG. 4C. or formed using other suitable techniques. In the illustrated configuration, the longitudinal axes of the splines 418 may be parallel to or generally parallel to the longitudinal axis of the hypotube 416. To prepare the device engagement component 310 for use, the splines 418 can be bent or otherwise flared radially outwardly to form the non-zero angle with the hypotube 416, as described above. Also in the illustrated configuration, the distal ends 420 of the splines 418 have not been bent to form the pushing surfaces 422. To facilitate bending of the distal ends 420 to form the pushing surfaces 422, each spline 418 can include a first set of notches 421a and a second set of notches 423a. The first set of notches 421a can provide a slightly weakened area of the splines 418 at the first bend region 421, and the second set of notches 423a can provide a slightly weakened area of the splines 418 at the second bend region 423. In this way, the notches 421a. 423a are expected to facilitate bending of the distal ends 420 at the first bend region 421 and the second bend region 423 to form the pushing surface 422.

[0048] FIG. 5A illustrates the assembly 300 of FIGS. 3-4C positioned within the delivery sheath 200 of FIG. 2 for assisting with delivery' of the shunting system 100 of FIGS. 1 A and IB. As illustrated, the splines 418 of the pusher section 314 can extend around the first canister 120. That is, the splines 418 are positioned between the first canister and an inner surface of the delivery sheath 200, such that the first canister 120 is positioned within the opening 419 (FIGS. 4A and 4B) defined by the splines 418. As a result, the distal ends 420 of the splines 418 with the flat pushing surfaces 422 (FIGS. 4A and 4B) are positioned distal to the first canister 120 within the delivery sheath 200. Advantageously, the pushing surfaces 422 (FIGS. 4A and 4B) can directly push on the anchor structure 1 10 (the distal ends 420 are shown slightly spaced apart from the anchor structure 110 in FIG. 5 A solely for clarity of illustration — in operation, the distal ends 420 directly abut, and thus can provide pushing forces directly upon, the anchor structure 110). Accordingly, the device engagement component 310 enables the assembly 300 to provide pushing forces directly against the anchor structure 110. as opposed to providing pushing forces on the proximal-most component in the delivery sheath 200 (i.e., the first canister 120). As a result of providing pushing forces directly on the anchor structure 110, the assembly 300 is expected to avoid or at least reduce the previously identified disadvantages of (a) having the first canister 120 move relative to, and potentially into, the anchor structure 110, and (b) deforming the first tether 121 and/or the electrical connector 126. In turn, this is expected to provide simpler and more consistent deployment of the system 100 from the delivery' sheath 200.

[0049] In operation, the assembly 300 pushes the shunting system 100 through the delivery' sheath 200 until the shunting system 100 is proximate the target deployment location. For example, in the context of deploying the shunting system 100 across a septal wall S between a right atrium RA and a left atrium LA as shown in FIG. 5B, a distal end of the delivery sheath 200 can be positioned through a hole or other opening O in the septal wall S and in fluid communication with the left atrium LA. The delivery sheath 200 can then be retracted relative to the assembly 300 and the shunting system 100 until the second canister 122 and a portion of the anchor structure 110 (e.g., the second petals 110b shown in FIG. 1A) exit the distal end of the delivery sheath 200. In other embodiments, the shunting system 100 can be pushed out of the distal end of the delivery sheath 200 in addition to or in lieu of retracting the delivery sheath 200 by continuing to provide pushing forces against the shunting system 100 via the assembly 300. Regardless, once the second petals 110b of the anchor structure 110 exit the delivery sheath 200 and are no longer radially constrained, the second petals 110b begin to expand outwardly toward the deployed configuration and contact the left atrial side of the septal wall S, as shown in FIG. 5C. The second canister 122 is pulled into apposition with the second petals 110b, e.g., via the second tether 123

[0050] With the shunting system 100 partially deployed in the left atrium LA, the delivery sheath 200 can be further retracted until the first appendages 110a of the anchor structure 110 and the first canister 120 exit a distal end of the delivery sheath 200. This can be done by retracting the delivery sheath 200 while maintaining a position of the assembly 300. Once the first petals 110b of the anchor structure 110 exit the delivery' sheath 200 and are no longer radially constrained, the first petals 110b expand outwardly toward the deployed configuration and contact the right atrial side of the septal wall S, as shown in FIG. 5D. Further, because the splines 418 of the pusher section 314 extend around the first canister 120, the splines 418 also exit a distal end of the delivery' sheath 200. In some embodiments, the splines 418 are at least partially radially compressed when positioned within the delivery sheath 200 such that the splines 418 expand at least partially radially outwardly (e.g.. the splines 418 open more) when advanced out of the delivery' sheath 200, as also shown in FIG. 5D. This enables release of the first canister 120 from within the splines 418 during deployment of the shunting system 100. As shown in FIG. 5E. the expansion of the first petals 110a also pulls the first canister 120 into opposition with the first petals 110a and out of the pusher section 314 of the assembly 300 via the first tether 321. Once the shunting system 100 is deployed, the pusher section 314 can be retracted back into the delivery sheath 200, and the delivery sheath 200 and the assembly 300 can be withdrawn from the patient.

[0051] In some embodiments, the assembly 300 can include one or more additional features that assist with releasing the first canister 120 from within the pusher section 314 of the assembly 300. For example, as shown in FIG. 5F, the assembly 300 can include a pusher or push rod 560 extending coaxially within the catheter 302. During delivery, the push rod 560 remains proximal to the pusher section 314 of the device engagement component 310. However, if the first canister 120 remains within the pusher section 314 after the anchor structure 110 is deployed (e.g., if the first canister 120 gets “stuck” within the splines 418, e.g., in the stage shown in FIG. 5D), the push rod 560 can be advanced distally to physically push the first canister 120 out of the pusher section 314. This can be done by removing the actuator guard 354 on the handle 350, and sliding the actuator 352 in a distal direction along a slot 351. In some embodiments, the push rod 560 is expected to be a secondary or fail-safe mechanism used to assist in the event that the first canister 120 fails to deploy from within the pusher section 314, and thus is not expected to be used during most procedures.

[0052] FIGS. 6A-6C illustrate another embodiment of a pusher catheter assembly 600 configured in accordance with select embodiments of the present technology⁷. In particular, FIG. 6A is an isometric view of the assembly 600, FIG. 6B is a cross-sectional view showing a first embodiment of an internal portion of the assembly 600 taken along the line indicated in FIG. 6A, and FIG. 6C is a cross-sectional view showing a second embodiment of the internal portion of the assembly 600 also taken along the line indicated in FIG. 6A. Referring first to FIG. 6A, the assembly 600 can be generally similar to the assembly 300 described with reference to FIGS. 3-5F. Relative to the assembly 300 of FIGS. 3-5F, the assembly 600 is configured for use with a guidewire 640 (e.g., for “over the wire” procedures). As shown, the guidewire 640 can extend through an entire axial length of the assembly 600 between a proximal end 600a configured to remain external to the patient during an implant procedure and a distal end 600b of the assembly 600 having a device engagement component or feature 610. In particular, the guidewire 640 extends through an elongate pushing catheter 602 (“the catheter 602”) and both a tubular section 612 and a pusher section 614 of the device engagement component 610. As described in detail with reference to FIGS. 6B and 6C, the catheter 602 can include one or more lumens or channels that enable the guidewire 640 to pass therethrough. The tubular section 612 and the pusher section 614 can have a generally open/hollow interior that also permits the guidewire 640 to pass therethrough.

[0053] Referring to FIG. 6B, the catheter 602 can be generally solid along its cross-section with a guidewire lumen 604 (“the lumen 604”) formed therein. The lumen 604 can extend through a full axial length of the catheter 602. Accordingly, the lumen 604 enables the guidewire 640 to extend through the catheter 602 from the proximal end 600a (FIG. 6A) of the assembly 600 to the device engagement component 610 (FIG. 6 A). Alternatively, and referring to FIG. 6C, the catheter 602 can have a generally hollow interior 603. A guidewire tube 605 can extend within the hollow interior 603 of the catheter 602 and through a full axial length of the catheter 602. The guidewire tube 605 can have a lumen extending therethrough for receiving the guidewire 640. Accordingly, similar to the guidewire lumen 604 of the embodiment shown in FIG. 6B, the guidewire tube 605 enables the guidewire 640 to extend through the catheter 602 from the proximal end 600a (FIG. 6A) of the assembly 600 to the device engagement component 610 (FIG. 6A). Although not shown, the catheter 602 can include a push rod generally similar to the push rod 560 of FIG. 5F and that also extends through the lumen 604 or the guidewire tube 650, in addition to the guidewire 640. Alternatively, the catheter 602 can include a separate lumen or tube for receiving the push rod.

[0054] Regardless of the embodiment, enabling guidewire access through the assembly 600 may be useful for facilitating certain procedures. For example, providing guidewire access through the assembly 600 enables the assembly 600 to be advanced over a pre-placed guidewire (e.g.. an “over the wire” procedure), which is expected to simplify certain percutaneous procedures. Similarly, providing guidewire access through the assembly 600 enables the guidewire 640 to extend through an implantable shunting system (not shown) carried within a portion of a delivery sheath distal to the assembly 600. When the system is deployed via pushing forces provided by the assembly 600, the guidewire 640 can extend through a lumen of the shunting system. For example, in the context of an implantable interatrial shunt, the guidewire 640 can extend through the shunting element and into the left atrium following deployment of the shunting element across the atrial septum. Providing left atrium guidewire access following shunt deployment may be beneficial if further left atrial access is needed (e.g., to implant another device, to reposition a previously implanted device, to recapture a previously implanted device, etc.).

[0055] FIGS. 7A-7C illustrate yet another embodiment of a device engagement component 710 for use with a pushing catheter assembly and configured in accordance with select embodiments of the present technology. In particular, FIG. 7A is a first isometric view' of the device engagement component 710 during a stage of manufacture. FIG. 7B is a second isometric view of the device engagement component 710 in an operational state, and FIG. 7C is an enlarged view- of a portion of the device engagement component 710.

[0056] The device engagement component 710 includes certain features generally similar to the device engagement component 310 of FIGS. 3-5F. For example, referring collective to FIGS. 7A and 7B, the device engagement component 710 can include a tubular section 712 having a hypotube 716 and a pusher section 714 having a plurality of splines or appendages 718. Although not shown, the tubular section 712 can be coupled to an elongate pushing catheter (e.g., the catheter 302; FIG. 3), similar to the tubular section 312 of the device engagement component 310, described above with reference to FIGS. 3-5F. Further, although shown in FIGS. 7A and 7B as being a solid cut pattern, the hypotube 716 can have one or more relief patterns, similar to the hypotube 316 and described in greater detail below with reference to FIG. 7C.

[0057] The splines 718 are arranged in a generally annular configuration to form a cylindrical or conical shaped opening 719 between radially inner surfaces of the splines 718. As shown by comparing FIGS. 7A and 7B, the splines 718 can flare slightly outwardly relative to the hypotube 716 to assist with receiving a first component of a catheterized medical device within the opening 419, similar to the splines 318 described with reference to FIGS. 4A-4C. The splines 718 can also have distal ends 720 with pushing surfaces 722 (FIG. 7B) for transmitting forces to a second component of a catheterized medical device, as also previously described. When folded radially inward as show n in FIG. 7B, the distal ends 720 of the splines 718 can also sen e as a ramp for assisting with releasing the first component of the catheterized medical device from within the opening 719 during device deployment.

[0058] Relative to the device engagement component 310 of FIGS. 3-5F, however, individual splines 718 are not all equally spaced relative to one another. As best shown in FIG. 7A, a first spline 718a is separated from a second spline 718b by a first gap G1 , the second spline 718b is separated from a third spline 718c by another gap (not shown) that is generally similar to or the same as the first gap Gl, and so on. Notably, however, a sixth spline 718f is separated from the first spline 718a by a second gap G2 that is larger than the first gap Gl. In some embodiments, the second gap G2 is between 100% and 1,000% wider than the first gap Gl, although other relative sizes are possible.

[0059] The width of the first gap Gl and the second gap G2 can be generally constant along the length of the corresponding splines 718 when the pusher section 714 is in the configuration shown in FIG. 7A. The gaps can have a width of between about 0.02 mm and about 5.0 mm. For example, the first gap Gl can have a first width of between about 0.02 mm and 2.0 mm, or between about 0.1 mm and about 1.5 mm, or between about 0.5 mm and about 1.2 mm, and the second gap can have a second width of between about 0.1 mm and about 5.0 mm, or between about 0.1 mm and about 3mm, although in other embodiments the first gap Gl and the second gap G2 can have widths outside the foregoing ranges. As shown in FIG. 7B, the distance between the splines 718 (and thus the width of the first gap G1 and the second gap G2) varies along the length of the splines 718 once the splines 718 are flared radially outwardly. While the proximal-most portion of the gaps (e.g., at the interface between the tubular section 712 and the pusher section 714) can remain the same or about the same as the gap width in the configuration shown in FIG. 7A, the gap width increases moving from the proximal to distal direction along the length of the splines 718. However, the second gap G2 remains wider than the other gaps along the length of the splines 718.

[0060] Without intending to be bound by theory, forming the pusher section 715 to have different gap widths is expected to provide several advantages. First, by having the majority of the splines 718 spaced apart by a relatively small gap (e.g., the first gap Gl), the splines 718 may have greater structural integrity and thus be able to better transmit pushing forces to the pushing surfaces 722. This is because, for any given number of splines 718 that form the pusher section 714, individual splines 718 can have a greater width if the gaps betw een individual splines 718 is minimized. In other w ords, relatively more of a circumference of the pusher section 714 is formed by solid structure of the splines 718 rather than void space of the gaps, e.g., as compared to the embodiment shown in FIGS. 3-5F. Second, the second gap G2 can be sized and shaped to accommodate one of more features of the catheterized medical device. For example, the second gap G2 can accommodate a guidewire (and/or guidewire lumen) that extends through the entire length of the device engagement component 710.

[0061] Moreover, although shown as having one pair of splines 718 separated by a relatively larger gap and the remaining pairs of splines 718 separated by relatively smaller gaps, in other embodiments, the pusher section 714 can have other designs. For example, there can be a combination of multiple smaller gaps and multiple larger gaps (e.g., to accommodate additional portions of a catheterized medical device). As another example, one or more of the smaller gaps may be at least partially angled or tapered even when in the cylindrical configuration shown in FIG. 7 A. This can accommodate one or more portions of a catheterized medical device that, in operation, is located at the distal end of the splines 718 but not the proximal end.

[0062] Referring next to FIG. 7C, a portion of the hypotube 716 of the tubular section 712 is shown. As shown, the tubular section 712 can include a laser cut or otherwise formed relief pattern that enables the tubular section 712 to bend or curve (e.g., in some or all directions) without reducing or substantially reducing axial stiffness (e.g., without detrimentally increasing axial compressibility of the hypotube 716). For example, in the illustrated embodiment the hypotube 716 has an interrupted cut spiral pattern, although other patterns can be used. As described above with reference to the hypotube 416 of FIGS. 4A and 4B, the pattern is expected to advantageously increase the efficiency with which pushing forces are transmitted from a push rod (not shown) to the pusher section 714 of the device engagement component 710, while retaining the ability of the hypotube 716 to curve and/or bend as it advances through a catheter.

[0063] Although described in the context of shunting systems, the pusher catheter assemblies described herein, including the assembly 300 of FIGS. 3-5F, the assembly 600 of FIGS. 6A-6C, and the device engagement component 710 of FIGS. 7A-7C, are expected to be useful for delivering other implantable medical devices, particularly devices in which the component that provides the most friction during deployment does not reside in the proximal- most position within the delivery sheath. This is because, as described in detail above, the pusher catheter assemblies described herein enable the pusher to bypass one or more proximal components of a catheterized implantable medical device to provide pushing forces directly upon the portion of the device expected to provide the greatest amount of frictional resistance during deployment of the device from the delivery sheath. Accordingly, the pusher catheter assemblies described herein are not limited to use with a particular implantable device, unless the context clearly dictates otherwise.

C. Select Embodiments of Introducer Systems for Loading Implantable Medical Devices into a Delivery Sheath

[0064] The present technology further includes an introducer system for loading a pusher catheter assembly and an implantable shunting system or other medical device into a delivery sheath or catheter. FIGS. 8A-8C, for example, illustrate an introducer system 800 configured in accordance with select embodiments of the present technology. More specifically, FIG. 8A is a partially offset front view of the introducer system 800, FIG. 8B is an isometric view of a loading assembly 820 of the introducer system 800, and FIG. 8C is a cross-sectional side view of the introducer system 800 showing the system 100 of FIGS. 1A and IB with the assembly 300 of FIGS. 3-4C being loaded into the delivery sheath 200 of FIG. 2 using the introducer system 800.

[0065] Referring first to FIG. 8A, the introducer system 800 includes an introducer 805, a first hemostasis valve 810, and a loading assembly 820 having a device loading tube 822 and a second hemostasis valve 824. The introducer 805 can be a sheath or other suitable structure known in the art for coupling with, and permitting an implantable medical device (e.g., the system 100 of FIGS. 1A and IB) to be positioned within, a delivery sheath (such as the delivery' sheath 200 of FIGS. 2 and 3. not shown in FIG. 8A). The first hemostasis valve 810 can provide controlled access to the introducer 805. The loading assembly 820 can assist with collapsing a medical device such as the system 100 of FIGS. 1 A and IB into a delivery configuration so that it can be advanced through the first hemostasis valve 810 and loaded into a delivery sheath coupled to/positioned within the introducer 805.

[0066] Referring now to FIG. 8B, the loading assembly 820 includes the loading tube 822 and the second hemostasis valve 824. The loading tube 822 can be a hollow tube that has a first (e.g., proximal) end portion 822a coupled (e.g., sealingly coupled) to the second hemostasis valve 824 and a second (e.g., distal) end portion 822b configured to be coupled (e.g., sealingly coupled) to the first hemostasis valve 810 (FIG. 8A). The loading tube 822 can be composed of a generally rigid material such a plastic, and have a length of between about 10 cm and about 100 cm. As described in detail below with reference to FIG. 8C, an implantable medical device can be collapsed into a delivery configuration and pre-loaded into the loading tube 822 before the loading tube 822 is coupled to the first hemostasis valve 810 of the introducer system 800.

[0067] The second hemostasis valve 824 can provide controlled access to the loading tube 822 via an access port 826. The second hemostasis valve 824 can further include a side port 827 coupled to a stopcock valve 828 via tubing 829. Together, the side port 827. stopcock valve 828, and tubing 829 can provide controlled fluidic access to an interior of the introducer system 800 and/or an associated delivery' sheath.

[0068] In operation, an implantable medical device (e.g., the system 100 of FIGS. 1A and IB) can be loaded into the loading tube 822. In some embodiments, a pusher system (e.g., the assembly 300 of FIGS. 3-4C or the assembly 600 of FIGS. 6A-6C) can be loaded into the loading tube 822 before and/or during loading the device into the loading tube. For example, a pusher catheter assembly can be advanced through the second hemostasis valve 824 (via the access port 826) and through the loading tube 822 until a distal end of the pusher catheter assembly (e.g., a device engagement component, such as the device engagement component 310 of the assembly 300) extends past the distal end 822b of, and therefore out of, the loading tube 822. The pusher catheter assembly can then "grab" a portion of the device via the device engagement component extending out of the distal end 822b of the loading tube 822 and “pull” the collapsed device into the loading tube 822 via the distal end 822b. As another example, a device and a pusher catheter assembly can be advanced into the loading tube 822 from the proximal end 822a via the access port 826.

[0069] FIG. 8C shows the system 100 of FIGS. 1A and IB and the assembly 300 of FIGS. 3-4C positioned within the loading tube 822. With the system 100 and the assembly 300 positioned within the loading tube 822, the loading tube 822 can be advanced through the first hemostasis valve 810 and into the introducer 805. The loading tube 822 can be advanced until the distal end portion 822b contacts a shoulder 807 within the introducer 805. The assembly 300 can then be used to push the system 100 out of the distal end portion 822b of the loading tube 822 (which cannot advance further distally due to engagement of the shoulder 807) and into the delivery sheath 200. This can be performed by imparting pushing forces on the assembly 300 via a portion of the assembly 300 proximal to the second hemostasis valve. Once the system 100 is positioned within the delivery sheath 200, the assembly 300 can be further utilized to push the system 100 toward a distal end (not shown) of the delivery sheath 200 for deployment of the system 100 within the patient, as described previously herein.

[0070] FIGS. 9A-9E illustrate another introducer system 900 configured in accordance with select embodiments of the present technology. More specifically, FIG. 9A is a side view of the introducer system 900, and FIG. 9B is a cross-sectional side view' of an introducer 905 and a first hemostasis valve 910 of the introducer system 900 of FIG. 9A. FIG. 9C is an isometric view of a portion of the introducer system 900 including a loading assembly 920, and FIG. 9D is another isometric view of the portion of the introducer system 900 shown in FIG. 9C but rotated 180 degrees relative to the view' of FIG. 9C. FIG. 9E is an enlarged side view' of a portion of the introducer system 900 showing a coupling between the loading assembly 920 and the introducer first hemostasis valve 910.

[0071] The introducer system 900 can include certain features that are generally similar to certain features of the introducer system 800 descnbed with reference to FIGS. 8A-8C. For example, referring first to FIG. 9A, the introducer system 900 can include an introducer 905, a first hemostasis valve 910, and a loading assembly 920. The introducer 905 can be a sheath or other suitable structure known in the art for coupling with, and permitting an implantable medical device to be positioned within, a delivers’ sheath. The first hemostasis valve 910 can provide controlled access to the introducer 905. The first hemostasis valve 910 can include a first side port 907 coupled to a first stopcock valve 908 via first tubing 909 to provide controlled fluidic access to an interior of the introducer system 900 and/or an associated delivery sheath. As shown in the cross-sectional view of FIG. 9B, the first hemostasis valve 910 can also include a first valve structure 910a (e.g., an orifice valve) and a second valve structure 910b (e.g., a cross slit valve). A rigid spacer 911 can be positioned between the first valve structure 910a and the second valve structure 910b to prevent or at least reduce air from being introduced into the introducer 905. The first hemostasis valve 910 can further include an annular stop 917 sized and shaped to interface with a distal end of the loading tube 922 (FIG. 9 A) when the loading tube 922 is inserted into the first hemostasis valve 910, described in greater detail below.

[0072] Returning to FIG. 9A, the loading assembly 920 can include the loading tube 922 and a second hemostasis valve 924. Similar to the embodiment described above with reference to FIGS. 8A-8C, the loading tube 922 can be inserted into the first hemostasis valve 910 to assist with loading an implantable medical device (not shown) into the introducer 905. Relative to the embodiment of FIGS. 8A-8C, the loading assembly 920 further includes a connection mechanism 930 to provide a releasably secure connection between the loading assembly 920 and the first hemostasis valve 910. In some embodiments, the connection mechanism 930 can be configured to rotationally and translationally lock the loading tube 922 to the first hemostasis valve 910 and/or the introducer 905. Additional details regarding the connection mechanism 930 are described below with reference to FIGS. 9C-9E. The second hemostasis valve 924 can also include a second side port 927 coupled to a first stopcock valve 928 via second tubing 929 to provide controlled fluidic access to an interior of the introducer system 900 and/or an associated deliver}' sheath.

[0073] Referring collectively to FIGS. 9C and 9D, the connection mechanism 930 includes a rotatable collar 932 and a bonding tube 936. The bonding tube 936 extends circumferentially around and is coupled to the outer surface of the loading tube 922. The bonding tube 936 is bonded or otherwise coupled to the loading tube 922 such that it is rotatably and translationally fixed relative to the loading tube 922. As best shown in FIG. 9D, the bonding tube 936 includes one or more protrusions, ridges, or tongues 937 extending outwardly from a radially outer surface of the bonding tube 936. In particular, the illustrated embodiment shows two protrusions 937 spaced 180 degrees apart, although in other embodiments the bonding tube 936 can have more or fewer protrusions 937 with other relative positions around the loading tube 922.

[0074] The protrusions 937 can rotatably lock the loading tube 922 to the first hemostasis valve 910 and the introducer 905. For example, as best shown in FIG. 9C. the first hemostasis valve 910 can include an annular hub 912 with an opening 913 sized and shaped to receive the loading tube 922. A radially inner surface of the hub 912 can include a plurality’ of ridges 914 that form a plurality of grooves or slots 915 therebetween. In the illustrated embodiment, adjacent slots 915 are approximately 15 degrees apart, although in other embodiments there can be more or fewer ridges 914 and slots 915 with different relative positioning. The hub 912 can have an inner diameter that is slightly larger than an outer diameter of the bonding tube 936 such that when the loading tube 922 is inserted into the first hemostasis valve 910, the bonding tube 936 is positioned at least partially within the hub 912. As a result, the protrusions 937 can sit within corresponding slots 915 of the hub 912 to rotatably lock the bonding tube 926 and the first hemostasis valve 910, which in turn rotatably locks the loading tube 922 relative to the first hemostasis valve 910 and the introducer 905.

[0075] Without intending to be bound by theory, rotatably locking the loading tube 922 relative to the introducer 905 is expected to be advantageous because it provides control over the rotational orientation/position of a collapsed medical device (not shown). For example, by preventing the loading tube 922 from rotating relative to the introducer 905, an implantable medical device collapsed in the loading tube 922 will be loaded into the introducer 905 w ith the same relative rotational position. That is, by rotatably locking the loading tube 922 and the introducer 905, the rotational position of a collapsed medical device will remain constant as it is advanced from the loading tube 922 into the introducer 905. This is expected to be advantageous because it can inform the user the rotational orientation that the medical device will be ultimately deployed at. As an additional advantage, the relative rotational orientation of a collapsed medical device can be changed (e.g.. corrected) as it is loaded from the loading tube 922 into the introducer 905. For example, if the medical device w as loaded into the loading tube 922 offset by 30 degrees in the counterclockwise direction relative to a first clocking marker (e.g., a visual indicator such as a line, mark, or other feature; not shown) on the loading tube 922, the loading tube 922 can simply be coupled to the hub 912 using a pair of slots 915 that are offset by 30 degrees in the clockwise direction relative to a second clocking marker (e.g., a visual indicator such as a line, mark, or other feature; not shown) on the hub 912. Because the loading tube 922 and the introducer 905 are rotationally locked, advancing the medical device from the loading tube 922 into the introducer 905 will correct the rotation orientation of the medical device.

[0076] The rotatable collar 932 is translationally fixed to the bonding tube 936 and/or the loading tube 922, but is rotatably coupled to the bonding tube 936 and/or the loading tube 922. As best shown in FIG. 9D, the rotatable collar 932 includes one or more recesses or openings 933 on the inner circumference, which are connected to corresponding slots 934 in the rotatable collar 932. The illustrated embodiment shows two openings 933 spaced 180 degrees apart and two corresponding slots 934, although in other embodiments there can be more or fewer openings 933 and slots 934 with different relative positioning.

[0077] The openings 933 and the slots 934 can be sized and shaped to axially lock the loading tube 922 to the first hemostasis valve 910 and the introducer 905. For example, as best shown in FIG. 9C, a radially outer surface of the hub 912 can include a plurality of bosses or pins 916. In the illustrated embodiment, there are two pins 916 spaced 180 degrees apart (only one is visible in FIG. 9B), although in other embodiments there can be more or fewer pins 916. Indeed, the number of pins 916 generally corresponds to the number of openings 933 or slots

934 in the rotatable collar 932. To axially lock the loading tube 922 to the first hemostasis valve 910 and the introducer 905, the loading tube 922 can be inserted into the first hemostasis valve 910 such that the pin(s) 916 enter the corresponding slot(s) 934 via the opening(s) 933. With the pin 916 in the slot 934, and as best shown in FIG. 9E, the rotatable collar 932 can be rotated to move the pin 916 from a first end portion 934a of the slot 934 that is aligned with the opening 933 to a second end portion 934b of the slot 934 that is not aligned with the opening 933. The second end portion 934b of the slot 934 can optionally include a step forming a partially recessed notch 935 for releasably retaining the pin 916 at the second end portion 934b. With the pin 916 located at the second end portion 934b of the slot 934, the loading tube 922 is axially locked to the first hemostasis valve 910 and the introducer 905.

[0078] In addition to axially locking the loading tube 922 to the introducer 905, the pin 916/slot 934 connection can also assist with fully seating the loading tube 922 into the first hemostasis valve 910, e.g., against the annular stop 917 (FIG. 9B). For example, as shown in FIG. 9E, the slot 934 can be at least partially angled or slanted relative to the distal edge of the collar 932. As the collar 932 rotates, the pin 916 rides along the slanted slot 934, thereby forcing a distal end of the loading tube 922 to seat firmly against the annular stop 917 (FIG. 9B). Without intending to be bound by theory, this is expected to provide a seamless or substantially seamless interface between the loading tube 922 and the introducer 905 and/or associated delivery sheath. A seamless interface may be advantageous because any gaps between the loading tube 922 and the introducer 905 and/or associated delivery' sheath may permit the collapsed medical device to at least partially expand radially outward into the gap, making it more difficult to advance the device into the introducer 905 and/or associated sheath. [0079] Similar to the pusher catheter assemblies described herein, the introducer systems 800 and 900 are expected to be useful for loading other implantable medical devices in addition to shunting systems into delivery sheath. Accordingly, the introducer systems described herein are not limited to use with a particular implantable device, unless the context clearly dictates otherwise.

[0080] As one of skill in the art will appreciate from the disclosure herein, various components of the systems described above can be omitted without deviating from the scope of the present technology. Likewise, additional components not explicitly described above may be added to the systems without deviating from the scope of the present technology. Moreover, the features described herein can be incorporated into other types of implantable medical devices beyond shunting systems. Accordingly, the present technology' is not limited to the configurations expressly identified herein, but rather encompasses variations and alterations of the described systems.

D. Examples

[0081] Several aspects of the present technology⁷ are set forth in the following examples:

1. A pusher catheter assembly for deploying an implantable shunting system within a patient, the implantable shunting system having a canister positioned proximally to an anchor structure when collapsed into a delivery⁷ sheath, the pusher catheter assembly comprising: a catheter having an outer diameter that is less than an inner diameter of the delivery' sheath; and a device engagement component coupled to an end portion of the catheter, wherein the device engagement component includes a pusher section sized and shaped to at least partially bypass the canister and to directly engage the anchor structure, wherein the pusher catheter assembly is configured to transmit pushing forces to the anchor structure via the catheter and the device engagement component.

2. The pusher catheter assembly of example 1 wherein the pusher catheter assembly is configured to transmit pushing forces to the anchor structure without directly pushing on the canister. 3. The pusher catheter assembly of example 1 wherein the pusher catheter assembly is configured to transmit pushing forces to both the anchor structure and the canister.

4. The pusher catheter assembly of any of examples 1 -3 wherein the pusher section includes a plurality of splines defining an opening for receiving the canister.

5. The pusher catheter assembly of example 4 wherein the plurality of splines extend between a first end portion and a second end portion, and wherein at least some of the plurality of splines include a bend proximate the second end portion to form a pushing surface normal to a longitudinal axis extending along an axial length of the pusher catheter assembly.

6. The pusher catheter assembly of example 5 wherein the pushing surface is oriented at about a 90 degree angle relative to an axial length of the plurality of splines.

7. The pusher catheter assembly of any of examples 4-6 wherein an axial crosssection of the plurality of splines is substantially flat.

8. The pusher catheter assembly of any of examples 4-7 wherein the splines are transitionable between a substantially cylindrical position and a flared position, and wherein adjacent splines are separated by corresponding gaps.

9. The pusher catheter assembly of example 8 wherein, when in the cylindrical position, a first pair of splines is separated by a first gap having a first width and a second pair of splines is separated by a second gap having a second width greater than the first width.

10. The pusher catheter assembly of example 9 wherein the second width is between 100% and 1,000% greater than the first width.

11. The pusher catheter assembly of example 9 wherein the second gap is sized and shaped to accommodate a guidewire and/or guidewire lumen that extends through the pusher catheter assembly. 12. The pusher catheter assembly of any of examples 1-11 wherein the device engagement component further includes a tubular section positioned between the catheter and the pusher section.

13. The pusher catheter assembly of example 12 wherein the tubular section includes a hypotube having a relief pattern.

14. The pusher catheter assembly of example 12 or example 13 wherein a central axis of the tubular section forms a non-zero angle with the plurality of splines.

15. The pusher catheter assembly of any of examples 1-14 wherein the pusher catheter assembly includes a guidewire lumen permitting a guidewire to extend through the pusher catheter assembly.

16. The pusher catheter assembly of any of examples 1-14, further comprising an actuatable push rod extending within the catheter, wherein the actuatable push rod is configured to advance distally through the device engagement component in response to being actuated.

17. A pusher catheter assembly for use with deploying an implantable medical device from a delivery' sheath at a target anatomical site within a patient, the pusher catheter assembly comprising: an elongated catheter extending between a first end portion and a second end portion, and a device engagement component coupled to the second end portion of the elongated catheter, wherein the device engagement component includes a pusher section sized and shaped to (a) bypass a first component of the implantable medical device, and (b) engage a second component of the implantable medical device positioned distal to the first component, wherein pushing forces induced via the elongated catheter are configured to be transmitted to the second component via the device engagement component. 18. The pusher catheter assembly of example 17 wherein the pusher section includes a plurality of splines configured to extend between the first component and an inner surface of the delivery sheath.

19. The pusher catheter assembly of example 18 wherein the plurality of splines: define an opening for receiving the first component; and have one or more flat surfaces for pushing the second component.

20. The pusher catheter assembly of any of examples 17-19 wherein the device engagement component further includes a tubular section configured to resist axial compression while permitting lateral bending.

21. The pusher catheter assembly of example 20 wherein the tubular section includes a hypotube having a relief pattern.

22. The pusher catheter assembly of any of examples 17-20, further comprising a guidewire lumen extending through at least the elongated catheter.

23. A device engagement component for use with a catheter for pushing an implantable medical device through a delivery sheath, the device engagement component comprising: a tubular section extending between a proximal end portion and a distal end portion, wherein the tubular section is configured to bend in one or more directions without being axially compressed, wherein the proximal end portion of the tubular section is coupleable to the catheter; and a pusher section extending from the distal end portion of the tubular section, wherein the pusher section includes a plurality of splines forming an opening therebetween, wherein the splines are configured to (a) flex at least partially radially outwardly when the opening receives a first component of the implantable medical device, and (b) transmit pushing forces from the catheter to a second component of the implantable medical device positionable distal to the opening. 24. The device engagement component of example 23 wherein: the plurality of splines includes at least a fist spline, a second spline, and a third spline. the first and second splines are separated by a first gap having a first width when the first and second splines are longitudinally inline with the tubular section, and the first and third splines are separated by a second gap having a second width when the first and third splines are longitudinal inline with the tubular section, the second width being at least 100% greater than the first width.

25. The device engagement component of example 23 or example 24 wherein individual splines of the plurality of splines include a distal end portion having a pushing surface extending perpendicular or about perpendicular to an axial length of the spline.

26. The device engagement component of example 25 wherein the distal end portion further includes an angled surface extending from the pushing surface, and wherein the angled surface is configured to act as a ramp to assist with releasing the first component from the opening.

27. The device engagement component of any of examples 23-26 wherein an outer surface of the tubular section includes an interrupted cut spiral pattern.

28. A system for loading an implantable medical device into a delivery⁷ sheath, the system comprising: an introducer sheath including a hemostasis valve; and a loading assembly including — a loading tube sized and shaped to (a) releasably hold the implantable medical device in a collapsed delivery configuration, and (b) be advanced at least partially into the hemostasis valve of the introducer sheath; and a connection mechanism configured to rotatably and axially lock the loading tube relative to the introducer sheath when the loading tube is advanced at least partially into the hemostasis valve. 29. The system of example 28 wherein the introducer includes a stop, and wherein the loading tube is configured to be advanced into the hemostasis valve until a distal end of the loading tube contacts the stop.

30. The system of example 28 or example 29 wherein: the connection mechanism includes a bonding tube rotatably and axially fixed to an outer surface of the loading tube, the bonding tube including at least one first tongue or groove, and the hemostasis valve includes a hub having at least one second tongue or groove configured to mate with a corresponding first tongue or groove of the connection mechanism to rotatably lock the loading tube relative to the introducer.

31. The system of any of examples 28-30 wherein: the connection mechanism includes a collar rotatably coupled to the loading tube, the collar having at least one slot therein, and the hemostasis valve includes a hub having at least one pin sized and shaped to be received in the slot, and the system is configured such that rotating the collar relative to the pin moves the pin from a first end portion of the slot to a second end portion of the slot and axially locks the loading tube to the hemostasis valve.

32. The system of example 29 wherein the second end portion of the slot includes a notch for releasably receiving the pin.

33. The system of example 29 or example 30 wherein the slot is angled relative to a proximal edge of the connection mechanism.

34. A method of loading an implantable medical device into a delivery sheath, the method comprising: advancing a pusher catheter assembly having a device engagement component through a first hemostasis valve and a tube in a first direction until at least a portion of the device engagement component extends past a distal end of the tube; while the device engagement component extends past the distal end of the tube, releasably engaging one or more components of the implantable medical device using the device engagement component; retracting the pusher catheter assembly in a second direction opposite the first direction until the device engagement component and the implantable medical device are positioned within the tube; advancing the tube carrying the device engagement component and the implantable medical device through a second hemostasis valve coupled to an introducer sheath; and pushing the implantable medical device into the delivery sheath coupled to the introducer sheath using the pusher catheter assembly.

E. Conclusion

[0082] Embodiments of the present disclosure may include some or all of the following components: a battery, supercapacitor, or other suitable power source; a microcontroller, FPGA, ASIC, or other programmable component or system capable of storing and executing software and/or firmware that drives operation of an implant; memory such as RAM or ROM to store data and/or software/firmware associated with an implant and/or its operation; wireless communication hardware such as an antenna system configured to transmit via Bluetooth, WiFi, or other protocols known in the art; energy harvesting means, for example a coil or antenna which is capable of receiving and/or reading an externally-provided signal which may be used to power the device, charge a battery, initiate a reading from a sensor, or for other purposes. Embodiments may also include one or more sensors, such as pressure sensors, impedance sensors, accelerometers, force/strain sensors, temperature sensors, flow sensors, optical sensors, cameras, microphones or other acoustic sensors, ultrasonic sensors, ECG or other cardiac rhythm sensors, SpO2 and other sensors adapted to measure tissue and/or blood gas levels, blood volume sensors, and other sensors known to those who are skilled in the art. Embodiments may include portions that are radiopaque and/or ultrasonically reflective to facilitate image-guided implantation or image guided procedures using techniques such as fluoroscopy, ultrasonography, or other imaging methods. Embodiments of the system may include specialized delivery catheters/sy stems that are adapted to deliver an implant and/or carry out a procedure. Systems may include components such as guidewires, sheaths, dilators, and multiple deliver}' catheters. Components may be exchanged via over- the- wire, rapid exchange, combination, or other approaches.

[0083] The above detailed description of embodiments of the technology are not intended to be exhaustive or to limit the technology to the precise forms disclosed above. Although specific embodiments of, and examples for, the technology are described above for illustrative purposes, various equivalent modifications are possible within the scope of the technology as those skilled in the relevant art will recognize. For example, although steps are presented in a given order, alternative embodiments may perform steps in a different order. The various embodiments described herein may also be combined to provide further embodiments. For example, although this disclosure has been written to describe devices that are generally described as being used to create a path of fluid communication between the left atrium and the right atrium, it should be appreciated that similar embodiments could be utilized for shunts between other chambers of the heart or for shunts in other regions of the body.

[0084] Unless the context clearly requires otherwise, throughout the description and the examples, the words “comprise;’ “comprising,” and the like are to be construed in an inclusive sense, as opposed to an exclusive or exhaustive sense; that is to say, in the sense of “including, but not limited to.” As used herein, the terms “connected,” “coupled,” or any variant thereof, means any connection or coupling, either direct or indirect, between two or more elements; the coupling of connection between the elements can be physical, logical, or a combination thereof. Additionally, the words “herein,” “above,” “below,” and words of similar import, when used in this application, shall refer to this application as a whole and not to any particular portions of this application. Where the context permits, words in the above Detailed Description using the singular or plural number may also include the plural or singular number respectively. As used herein, the phrase “and/or” as in “A and/or B” refers to A alone, B alone, and A and B. Additionally, the term “comprising” is used throughout to mean including at least the recited feature(s) such that any greater number of the same feature and/or additional types of other features are not precluded. It will also be appreciated that specific embodiments have been described herein for purposes of illustration, but that various modifications may be made without deviating from the technology. Further, while advantages associated with some embodiments of the technology⁷ have been described in the context of those embodiments, other embodiments may also exhibit such advantages, and not all embodiments need necessarily exhibit such advantages to fall within the scope of the technology. Accordingly, the disclosure and associated technology can encompass other embodiments not expressly shown or described herein.

Claims

CLAIMS I/'W e claim:

1. A pusher catheter assembly for deploying an implantable shunting system within a patient, the implantable shunting system having a canister positioned proximally to an anchor structure when collapsed into a delivery sheath, the pusher catheter assembly comprising: a catheter having an outer diameter that is less than an inner diameter of the delivery sheath; and a device engagement component coupled to an end portion of the catheter, wherein the device engagement component includes a pusher section sized and shaped to at least partially bypass the canister and to directly engage the anchor structure, wherein the pusher catheter assembly is configured to transmit pushing forces to the anchor structure via the catheter and the device engagement component.

2. The pusher catheter assembly of claim 1 wherein the pusher catheter assembly is configured to transmit pushing forces to the anchor structure without directly pushing on the canister.

3. The pusher catheter assembly of claim 1 wherein the pusher catheter assembly is configured to transmit pushing forces to both the anchor structure and the canister.

4. The pusher catheter assembly of claim 1 wherein the pusher section includes a plurality of splines defining an opening for receiving the canister.

5. The pusher catheter assembly of claim 4 wherein the plurality of splines extend between a first end portion and a second end portion, and wherein at least some of the plurality of splines include a bend proximate the second end portion to form a pushing surface normal to a longitudinal axis extending along an axial length of the pusher catheter assembly.

6. The pusher catheter assembly of claim 5 wherein the pushing surface is oriented at about a 90 degree angle relative to an axial length of the plurality of splines.

7. The pusher catheter assembly of claim 4 wherein an axial cross-section of the plurality of splines is substantially flat.

8. The pusher catheter assembly of claim 4 wherein the splines are transitionable between a substantially cylindrical position and a flared position, and wherein adjacent splines are separated by corresponding gaps.

9. The pusher catheter assembly of claim 8 wherein, when in the cylindrical position, a first pair of splines is separated by a first gap having a first width and a second pair of splines is separated by a second gap having a second width greater than the first width.

10. The pusher catheter assembly of claim 9 wherein the second width is between 100% and 1,000% greater than the first width.

11. The pusher catheter assembly of claim 9 wherein the second gap is sized and shaped to accommodate a guidewire and/or guidewire lumen that extends through the pusher catheter assembly.

12. The pusher catheter assembly of claim 11 wherein the device engagement component further includes a tubular section positioned between the catheter and the pusher section.

13. The pusher catheter assembly of claim 12 wherein the tubular section includes a hypotube having a relief pattern.

14. The pusher catheter assembly of claim 12 wherein a central axis of the tubular section forms a non-zero angle with the plurality of splines.

15. The pusher catheter assembly of claim 1 wherein the pusher catheter assembly includes a guidewire lumen permitting a guidewire to extend through the pusher catheter assembly.

16. The pusher catheter assembly of claim 1, further comprising an actuatable push rod extending within the catheter, wherein the actuatable push rod is configured to advance distally through the device engagement component in response to being actuated.

17. A pusher catheter assembly for use with deploying an implantable medical device from a delivery’ sheath at a target anatomical site within a patient, the pusher catheter assembly comprising: an elongated catheter extending between a first end portion and a second end portion, and a device engagement component coupled to the second end portion of the elongated catheter, wherein the device engagement component includes a pusher section sized and shaped to (a) bypass a first component of the implantable medical device, and (b) engage a second component of the implantable medical device positioned distal to the first component, wherein pushing forces induced via the elongated catheter are configured to be transmitted to the second component via the device engagement component.

18. The pusher catheter assembly of claim 17 wherein the pusher section includes a plurality of splines configured to extend between the first component and an inner surface of the delivery sheath.

19. The pusher catheter assembly of claim 18 wherein the plurality' of splines: define an opening for receiving the first component; and have one or more flat surfaces for pushing the second component.

20. The pusher catheter assembly of claim 17 wherein the device engagement component further includes a tubular section configured to resist axial compression while permitting lateral bending.

21. The pusher catheter assembly of claim 20 wherein the tubular section includes a hypotube having a relief pattern.

22. The pusher catheter assembly of claim 17, further comprising a guidewire lumen extending through at least the elongated catheter.

23. A device engagement component for use with a catheter for pushing an implantable medical device through a delivery sheath, the device engagement component comprising: a tubular section extending between a proximal end portion and a distal end portion, wherein the tubular section is configured to bend in one or more directions without being axially compressed, wherein the proximal end portion of the tubular section is coupleable to the catheter; and a pusher section extending from the distal end portion of the tubular section, wherein the pusher section includes a plurality of splines forming an opening therebetween, wherein the splines are configured to (a) flex at least partially radially outwardly when the opening receives a first component of the implantable medical device, and (b) transmit pushing forces from the catheter to a second component of the implantable medical device positionable distal to the opening.

24. The device engagement component of claim 23 wherein: the plurality of splines includes at least a fist spline, a second spline, and a third spline. the first and second splines are separated by a first gap having a first width when the first and second splines are longitudinally inline with the tubular section, and the first and third splines are separated by a second gap having a second width when the first and third splines are longitudinal inline with the tubular section, the second width being at least 100% greater than the first width.

25. The device engagement component of claim 23 wherein individual splines of the plurality of splines include a distal end portion having a pushing surface extending perpendicular or about perpendicular to an axial length of the spline.

26. The device engagement component of claim 25 wherein the distal end portion further includes an angled surface extending from the pushing surface, and wherein the angled surface is configured to act as a ramp to assist with releasing the first component from the opening.

27. The device engagement component of claim 23 wherein an outer surface of the tubular section includes an interrupted cut spiral pattern.