Dilators for Vascular Access Systems and Related Devices and Methods

Abstract

Dilators for vascular access systems, as well as related devices and methods, are disclosed herein. In some embodiments, the dilator includes an elongate body having a diameter that is generally constant or uniform along the length of the body. The diameter can be sized to correspond to a catheter of the vascular access system, such that the dilator can be positioned within the catheter with little or no gap or spacing between the dilator and the interior of the catheter. Additionally or alternatively, the body of the dilator can include multiple body regions, each having one or more respective mechanical properties. In these and other embodiments, the dilator can be configured to couple with at least a portion of the vascular access system. For example, the dilator can include one or more notches configured to couple the dilator to the vascular access system via a valve of the vascular access system.

Description

[Technical field]

[0001] (CROSS REFERENCE TO RELATED APPLICATIONS) This application claims the benefit of U.S. Patent Application No. 63 / 338,266, filed May 4, 2022, and U.S. Patent Application No. 63 / 397,649, filed August 12, 2022, each of which is incorporated by reference in its entirety herein.

[0002] FIELD OF THEINVENTION The present technology relates generally to dilators for vascular access systems, and related devices and methods. [Background technology]

[0003] Thrombosis is the localized clotting or coagulation of blood in a part of the circulatory system, and a thrombus is a blood clot that forms in situ within the vascular system. A venous thrombosis is a blood clot that forms within a vein. A common type of venous thrombosis is deep vein thrombosis (DVT), which is the formation of a blood clot within a deep vein (e.g., primarily in the legs). Nonspecific symptoms of thrombosis may include pain, swelling, redness, warmth, and engorged superficial veins.

[0004] If the clot breaks off (embolizes) and travels toward the lungs, it can become a life-threatening pulmonary embolism (PE) (e.g., a blood clot in the lungs). In addition to the loss of life that can result from PE, DVT can cause significant health challenges, such as post-thrombotic syndrome, which can cause chronic swelling, pressure, pain, and ulcers due to damage to valves and blood vessels. Furthermore, DVT can result in significant medical costs, either directly or indirectly, through the treatment of associated complications and the patient's inability to work.

[0005] Existing methods for treating DVT and PE often involve treating the DVT or PE with a catheter system that is advanced through the patient's vasculature, such as along a venous access pathway. Such catheter systems, particularly those having a larger size (e.g., greater than 16 French), often include a navigation component, such as a smaller catheter or dilator, that can be used to dilate the patient's vasculature and guide the larger catheter to the target treatment site. For example, a larger catheter may be inserted through the navigation component, using the navigation component as a "rail" to guide the larger catheter to the target treatment site.

[0006] However, during advancement of the catheter through the vasculature, the navigation component and / or the catheter may encounter significant forces or resistance from the patient's vasculature. In some cases, this may result in the practitioner unintentionally injuring the patient by over-advancing a large catheter along the navigation component. Furthermore, forces against the navigation component may cause the navigation component to move or retract relative to the catheter. If the navigation component bends or flexes relative to the catheter, it may prevent the practitioner from advancing the navigation component and catheter together through the patient's vasculature. If the navigation component retracts sufficiently through the catheter, the edges of the catheter may be exposed, which may cause damage to the patient's percutaneous access site or vasculature. Summary of the Invention [Means for solving the problem]

[0007] The present technology is generally directed to navigation components ("dilators") for vascular access systems, as well as related devices and methods. In some embodiments, the dilator includes an elongate body having a diameter that is generally constant or uniform along the length of the body. The diameter can be sized to correspond to a catheter of the vascular access system, such that the dilator can be positioned within the catheter with little or no gap or spacing between the dilator and the interior of the catheter. In these and other embodiments, the body of the dilator can include multiple body regions, each having one or more respective mechanical properties. In at least some embodiments, for example, the dilator includes a first body region having a first flexibility profile and a second body region having a second flexibility profile that is greater than the first flexibility profile, such that the second body region is more flexible than the first body region. The second body region can be distal from the first body region, such that the less flexible / stiffer first body region can provide a portion of the expander to which force can be applied to advance the expander through the patient's vasculature, and the less stiff / more flexible second body region can provide improved navigational response and / or control while advancing the expander through the patient's vasculature.

[0008] Currently existing dilators may be tapered or angled to provide flexibility. For example, the diameter of the tapered dilator may decrease toward the distal tip of the tapered dilator, the decreased diameter providing increased flexibility toward the distal tip. However, these tapered dilators may be difficult to secure to a vascular access device such as a catheter. For example, the tapered shape of these dilators may lead to a gap or spacing between the tapered dilator and the catheter when the tapered dilator is positioned within the catheter, which may allow the tapered dilator to bend or flex within the catheter during use. This bending or flexing may reduce control and / or navigation precision during a procedure. In contrast to current angled dilators, the dilators of the present technology may have a generally constant or uniform diameter, which may improve the fit of these dilators within a vascular access device and / or reduce or prevent undesirable flexing or flexing of these dilators during a procedure. Additionally or alternatively, the mechanical properties of each of the dilator body regions may be selected to improve the flexibility of those dilators.

[0009] Additionally or alternatively, the dilator can be configured to couple with at least a portion of the vascular access system. In some embodiments, the dilator includes one or more notches. Each of the notches can extend at least partially or completely around a longitudinal axis of the body of the dilator and can be configured to couple the dilator to the vascular access system via a valve of the vascular access system. For example, the valve can include one or more internal components or tethers configured to open and / or close a path through the valve. When the dilator is positioned within the valve with one of the notches aligned with the tether, the tether can be at least partially inserted into the notch, thereby creating a resistance or interference fit that inhibits or prevents further movement of the dilator relative to the valve (and / or movement of the valve relative to the dilator). Each of the notches can be spaced along the length of the dilator such that when coupled via the valve, each notch can be associated with a different position of the dilator relative to the vascular access system and / or a different length of the dilator extending beyond the vascular access system. Because each notch can prevent further movement of the expander and / or vascular access system relative to one another, the location of the one or more notches can be configured to inhibit or prevent over-insertion of the expander and / or provide the user with increased control over the amount of the expander that extends beyond the vascular access system. [Brief description of the drawings]

[0010] Many aspects of the present technology can be better understood with reference to the following drawings. The components in the drawings are not necessarily to scale, emphasis instead being placed upon clearly illustrating the principles of the present disclosure.

[0011] [Figure 1] FIG. 1 is a partial schematic side view of a vascular access system constructed in accordance with the present technology. [Figure 2A] 2A and 2B are side and cross-sectional views, respectively, of a dilator configured in accordance with an embodiment of the present technology. [Figure 2B] 2A and 2B are side and cross-sectional views, respectively, of a dilator configured in accordance with an embodiment of the present technology. [Figure 2C] FIG. 2C is an enlarged perspective view of region 2C of the dilator shown in FIG. 2A in accordance with an embodiment of the present technology. [Figure 3A] 3A and 3B are side cross-sectional views of the dilator of FIGS. 2A-2C positioned within the valve of the vascular access system of FIG. 1 in accordance with an embodiment of the present technology. [Figure 3B] 3A and 3B are side cross-sectional views of the dilator of FIGS. 2A-2C positioned within the valve of the vascular access system of FIG. 1 in accordance with an embodiment of the present technology. [Figure 4A] 4A and 4B are perspective views of the dilator of FIGS. 2A-2C positioned within the vascular access system of FIG. 1 in accordance with an embodiment of the present technology. [Figure 4B] 4A and 4B are perspective views of the dilator of FIGS. 2A-2C positioned within the vascular access system of FIG. 1 in accordance with an embodiment of the present technology. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0012] Specific details are set forth in the following description and in Figures 1-4B to provide a thorough understanding of various embodiments of the present technology. In other instances, well-known structures, materials, operations, and / or systems often associated with endovascular procedures, clot removal procedures, catheters, and the like, are not shown or described in detail in the following disclosure to avoid unnecessarily obscuring the description of various embodiments of the present technology. However, one skilled in the art will recognize that the present technology can be practiced without one or more of the details set forth herein and / or with other structures, methods, components, and the like.

[0013] The terms used below should be interpreted in their broadest reasonable manner, even when used in conjunction with the detailed description of specific examples of embodiments of the present technology. Indeed, certain terms may even be emphasized below, however, any terms intended to be interpreted in any limited manner are expressly and specifically defined as such in this detailed description section.

[0014] The accompanying figures depict embodiments of the present technology and are not intended to limit its scope unless expressly indicated. The sizes of the various depicted elements are not necessarily drawn to scale, and these various elements may be enlarged to improve legibility. Details of components may be abstracted in the figures to exclude details such as the location of components and specific precise connections between such components when such details are not necessary for a complete understanding of how to create and use the present technology. Many of the details, dimensions, angles, and other features shown in the figures are merely illustrative of specific embodiments of the present disclosure. Thus, other embodiments can have other details, dimensions, angles, and features without departing from the present technology. In addition, those skilled in the art will understand that further embodiments of the present technology can be practiced without some of the details described below.

[0015] With respect to the terms "distal" and "proximal" herein, unless otherwise specified, these terms may refer to the relative location of portions of the catheter subsystem with respect to an operator and / or a location within the vasculature. Also, as used herein, designations such as "rear," "forward," "upper," "lower," etc. are not meant to limit the referenced components to a particular orientation. It is understood that such designations refer to the orientation of the referenced components as illustrated in the figures, and that the systems of the present technology may be used in any orientation suitable to the user.

[0016] FIG. 1 is a partial schematic side view of a vascular access system 100 ("system 100") configured in accordance with an embodiment of the present technology. System 100 may also be referred to as an aspiration assembly, a clot treatment system, a clot removal system, a thrombus removal system, an introducer sheath assembly, and / or the like. In the illustrated embodiment, system 100 includes a tubing assembly 110 fluidly coupled to a catheter 120 via a valve 130. In some embodiments, catheter 120 is an elongated member configured to be inserted into and through a patient's vasculature and used, for example, to treat clot material therein. In other embodiments, catheter 120 can be an introducer sheath configured to be inserted through a patient's skin and tissue tract to provide an access site across which other components (e.g., other catheters used to treat clot material) can easily access the vasculature. Thus, although referred to as a "catheter 120," catheter 120 may comprise an introducer sheath, an access sheath, and / or another type of elongate member configured to be inserted through the skin and tissue tracts and / or traverse the vasculature of a patient. Generally, system 100 (i) may include features generally similar or identical to those of the clot treatment system detailed in U.S. Patent Application No. 16 / 536,185, filed August 8, 2019, entitled "SYSTEM FOR TREATING EMBOLISM AND ASSOCIATED DEVICES AND METHODS," which is incorporated herein by reference in its entirety, and / or (ii) may be used to treat / remove clot material from a patient (e.g., a human patient) using any of the methods detailed therein.

[0017] In the illustrated embodiment, the catheter 120 includes a proximal region or portion 122a and a distal tip region or portion 122b opposite the proximal region 122a. The proximal region 122a can include a proximal end 126a of the catheter 120, and the distal tip region 122b can include a distal end 126b of the catheter 120. The catheter 120 further defines a lumen 124 (shown using a dashed line in FIG. 1 ) that extends completely therethrough from the proximal region 122a to the distal tip region 122b. The lumen 124 and / or the catheter 120 can at least partially define a longitudinal axis X of the system 100.

[0018] The valve 130 is fluidly coupled to the lumen 124 of the catheter 120 and may be integral with or coupled to the proximal region 122a of the catheter 120 such that these components move together. In some embodiments, the valve 130 is a hemostatic valve configured to maintain hemostasis during a clot removal procedure by preventing fluid flow in the proximal direction P through the valve 130 as various components, such as dilators, delivery sheaths, tensioning members, guidewires, interventional devices, other aspiration catheters, etc., are inserted through the valve 130 and delivered through the catheter 120 to a treatment site in a blood vessel. The valve 130 may include a bifurcation or side port 102 configured to fluidly couple the lumen 124 of the catheter 120 to the tubing assembly 110. In some embodiments, the valve 130 may be a valve of the type disclosed in U.S. patent application Ser. No. 16 / 117,519, filed Aug. 30, 2018, entitled “HEMOSTASIS VALVES AND METHODS OF USE,” which is incorporated by reference in its entirety.

[0019] In the illustrated embodiment, the tubing assembly 110 fluidly couples the catheter 120 to a pressure source 104, such as a syringe. The pressure source 104 may be configured to generate (e.g., form, create, fill, build up) a vacuum (e.g., a negative relative pressure) and build up the vacuum for subsequent application to the catheter 120. The tubing assembly 110 may include one or more tubing sections 112 (individually labeled as a first tubing section 112a and a second tubing section 112b), at least one fluid control device 114 (e.g., a valve), and at least one connector 116 (e.g., a Toomey tip connector) for fluidly coupling the tubing assembly 110 to the pressure source 104 and / or other suitable components. In some embodiments, the fluid control device 114 is a stopcock that is fluidly coupled (i) to the side port 102 of the valve 130 via a first tubing section 112a and (ii) to the connector 116 via a second tubing section 112b. The fluid control device 114 is externally operable by a user to regulate the flow of fluid therethrough, specifically from the lumen 124 of the catheter 120 to the pressure source 104. In some embodiments, the connector 116 is a quick-release connector (e.g., a quick-disconnect fitting) that allows for rapid coupling / discoupling of the catheter 120 and the fluid control device 114 to / from the pressure source 104.

[0020] During a clot treatment procedure, at least a portion of the system 100, such as the distal end 126b and / or distal tip region 122b of the catheter 120, may be inserted through the patient's vasculature. In some embodiments, the system 100 is inserted through an introducer sheath that traverses the patient's skin and tissue to provide an access site. When the catheter 120 is positioned at a desired location relative to the clot material (e.g., pulmonary embolism, deep vein thrombosis) within the patient, the user can first close the fluid control device 114 before creating a vacuum within the pressure source 104, for example, by withdrawing the plunger of a syringe coupled to the connector 116. In this manner, a vacuum is built (e.g., a negative pressure is maintained) within the pressure source 104 before the pressure source 104 is fluidly connected to the lumen 124 of the catheter 120. To aspirate the lumen 124 of the catheter 120, the user can open the fluid control device 114 to fluidly connect the pressure source 104 to the catheter 120, thereby applying or releasing the vacuum built up in the pressure source 104 to the lumen 124 of the catheter 120. The opening of the fluid control device 114 applies the built up vacuum pressure to the tubing assembly 110 and the catheter 120 instantaneously or near instantaneously, thereby creating a suction pulse throughout the catheter 120 that can aspirate the clot material into the catheter 120. In particular, suction is applied to the distal tip region 122b of the catheter 120 to suck / aspirate at least a portion of the clot material proximate the distal tip region 122b into the lumen 124 of the catheter 120. Additionally, or alternatively, the catheter 120 can act as an introducer sheath and can be inserted through the patient's skin and tissue partially into a blood vessel to provide an access point through which other medical instruments can be delivered and / or otherwise used to treat the patient.

[0021] 2A and 2B are side and cross-sectional views, respectively, of a navigation component or dilator 240 configured in accordance with an embodiment of the present technology. The dilator 240 is configured to be inserted into the catheter 120 of FIG. 1 and advanced with the catheter. The dilator 240 includes a generally elongated body 242 having a proximal region or portion 242a, a distal tip region or portion 242b opposite the proximal region 242a, and one or more body segments or regions 244 (individually identified as a first body region 244a and a second body region 242b) extending at least partially between the proximal region 242a and the distal tip region 244b. The dilator 240 may further include a tip 246 (e.g., an atraumatic tip) in or near the distal tip region 242b, a coupling component 248 in or near the proximal region 242a, and one or more notches 250 (e.g., an insertion locating feature). The coupling component 248 may include a twist lock connector, a luer connector, and / or another suitable coupling component and may be configured to couple or lock the expander 240 to a valve of a vascular access system, such as the valve 130 of the system 100 of FIG. 1. In the illustrated embodiment, the tip 246 is distal from the second body region 244b and the coupling component 248 is proximal from the first body region 244a. In other embodiments, the second body region 244b may include all or a portion of the tip 246 and / or the first body region 244a may include all or a portion of the coupling component 248 and / or may be positioned within it. The notch 250 is described in further detail below with reference to FIG. 2C.

[0022] In some embodiments, as shown in FIG. 2B, the body 242, tip 246, and / or coupling component 248 can be hollow such that a guidewire (not shown) can be positioned within the dilator 240 and used to aid in its navigation. In such embodiments, each of the body regions 244 has a first thickness T a and the second thickness T b The first and second thicknesses T may be individually labeled as a~bmay be the same or different, and / or each thickness T a~b may be constant or variable along all or part of the length of each body region 244a-b.

[0023] The first body region 244a, the second body region 244b, the tip 246, and / or the coupling component 248 may each be formed from one or more polymers and / or other suitable materials. For example, the first and second body regions 244a-b may be formed from the same or different materials.

[0024] Each of the body regions 244a-b has a first diameter D a and the second diameter D b In some embodiments, the diameter D of the body regions 244a-b may be individually labeled as a~b can be different from one another and / or can vary along their respective lengths, such that the first and second body regions 244a-b and / or one or more portions thereof can have different diameters. In the illustrated embodiment, the first and second diameters D a~b are generally similar or identical such that the body 242 of the dilator 240 has a substantially uniform diameter. In these and other embodiments, the diameter D a~b One or more of may correspond to and / or be smaller than an inner dimension of the catheter, such as the inner diameter of the lumen 124 of the catheter 120 (FIG. 1). Thus, the dilator 240 may be positioned within the catheter 120 (e.g., through the valve 130) with at least a portion of the tip 246 extending distally beyond the distal end 126b of the catheter 120 (FIG. 1).

[0025] Each of the body regions 244 can have one or more respective mechanical properties, such as hardness, stiffness, durometer, flexibility, stiffness, Young's modulus, density, etc. The mechanical properties (e.g., different durometers) can impart different flexibility profiles to the body regions 244. In some embodiments, individual ones of the body regions 244 can include one or more coils, braids, and / or other structures configured to, for example, increase or decrease the flexibility profile relative to one or more other body regions 244. In at least some embodiments, the first body region 244a has a first flexibility profile and the second body region 244b has a second flexibility profile that is greater than the first flexibility profile, such that the second body region 244b is less stiff / more flexible than the first body region 244a. For example, in the illustrated embodiment, the first body region 244a has a first durometer and the second body region 244b has a second durometer that is lower (e.g., less stiff / more flexible) than the first durometer. In some aspects of the present technology, the less stiff second body region 244b can improve the maneuverability of the dilator 240 during navigation through the vasculature, while the stiffer first body region 244a can improve control of and / or force transmission to the dilator (e.g., "pushability" and / or column strength) during navigation through the vasculature. Although the dilator 240 shown in FIGS. 2A and 2B includes two body regions 244a-b, in other embodiments, the dilator 240 can include more body regions 244, each of which can have one or more respective mechanical properties that are greater than, equal to, or less than one or more of the other body regions 244. Thus, in some embodiments, the dilator 240 includes two or more body regions 244 having the same diameter but different stiffness, durometer, flexibility, etc.

[0026] 2C is an enlarged perspective view of region 2C of FIG. 2A, in accordance with an embodiment of the present technology. In the illustrated embodiment, the cutout 250 defines / comprises a recessed area that extends at least partially or completely around the body 242 of the dilator 240, for example, circumferentially around the longitudinal axis Y of the body 242. Thus, the cutout 250 defines a first diameter D a and / or second diameter D b The third diameter D of the dilator 240 can be smaller than c In the illustrated embodiment, the notch 250 is positioned between the first body region 244a and the second body region 244b. In other embodiments, the notch 250 can be positioned at least partially within one or both of the body regions 244a-b. In these and other embodiments, the dilator 240 can include multiple notches 250, each of which can be positioned at least partially between the first body region 244a and the second body region 244b, at least partially within the first body region 244a, at least partially within the second body region 244b, or at another suitable location along the dilator 240.

[0027] 3A and 3B are cross-sectional side views of a dilator 240 positioned within a valve 130, in accordance with an embodiment of the present technology. More specifically, in FIG. 3A, the dilator 240 is in a first position within the valve 130, and in FIG. 3B, the dilator 240 has been moved (e.g., distally) to a second position within the valve 130, as indicated by arrow A. In FIG. 3A and 3B, the dilator 240 includes a notch 250 ("first notch 250") and an additional second notch 350 positioned proximally from the first notch 250. The second notch 350 may be at least generally similar or identical in structure and / or function to the first notch 250.

[0028] 3A and 3B together, the valve 130 includes a first or distal opening 332a, a second or proximal opening 332b, and a central lumen 334 extending therebetween. The distal opening 332a can be fluidly coupled to a catheter, such as the catheter 120 of FIG. 1. The valve 130 further includes a filament or tether 336 operably coupled to one or more actuators or buttons 338 (identified individually as a first button 338a and a second button 338b in FIGS. 3A and 3B). The tether 336 can be configured to open and / or close the central lumen 334 of the valve 130, for example, to form a substantially fluid-tight seal that blocks or prevents fluid communication between the distal opening 332a and the proximal opening 332b. In the illustrated embodiment, for example, button 338 is biased outwardly by spring 339 (individually identified in FIGS. 3A and 3B as first spring 339a and second spring 339b) to a first position shown in FIG. 3A. When buttons 338a-b are in the first position, buttons 338a-b pull tether 336 which is taught to tighten and seal central lumen 334. A user can press button 338 against the bias of spring 339 to a second position shown in FIG. 3B to relax tether 336, thereby relaxing central lumen 334 and releasing the seal. Generally, the valve 130 may (i) include at least some features that are generally similar or identical to those of the hemostasis valves described in detail in U.S. patent application Ser. No. 11,000,682, filed Aug. 30, 2018, entitled "HEMOSTASIS VALVES AND METHODS OF USE," which is incorporated herein by reference in its entirety, and / or (ii) be used to treat / remove clot material from a patient (e.g., a human patient) using any of the methods described in detail therein.

[0029] In some embodiments, the tether 336 is configured to releasably couple the dilator 240 to the valve 130 by interlocking with one of the notches 250, 350. For example, in the illustrated embodiment, the tether 336 tightens around the central lumen 334 when the buttons 338a-b are in a first position, as shown in FIG. 3A. Thus, when the dilator 240 is inserted through the proximal opening 332b, the first notch 250 is positioned in alignment with the tether 336, thereby allowing at least a portion of the tether 336 to be driven toward and / or into the first notch 250, creating a resistance force / interference fit that couples the dilator 240 to the valve 130. The resistance force / interference fit inhibits or prevents further movement (e.g., proximal and / or distal movement) of the dilator 240 relative to the valve 130.

[0030] The expander 240 can be decoupled from the valve 130 by actuating / pressing one or more of the buttons 338, as shown in FIG. 3B, to move the tether 336 radially outward, away from the longitudinal axis of the central lumen 334, and outward / outward from the first notch 250. Pressing / actuating one or more of the buttons 338 can thereby allow further movement (e.g., proximal and / or distal movement) of the expander 240 relative to the valve 130. In some embodiments, the resistance / interference fit can be overcome by applying an increased force to the expander 240 and / or valve 130, for example, to displace the tether 336 from the first notch 250 and allow further movement of the expander 240 and / or valve 130 relative to one another without pressing / actuating one or more of the buttons 338. In Figure 3B, the dilator 240 has been moved further distally through the valve 130 from a proximal position (Figure 3A) to a more distal position. In some embodiments, the dilator 240 can be advanced further distally until the second notch 350 is positioned in alignment with the tether 336. When the second notch 350 is aligned with the tether 336, the tether 336 can be driven radially into the second notch 350, as previously described with reference to the first notch 250, thereby recoupling the dilator 240 to the valve 130.

[0031] 1-3B together, the dilator 240 can be inserted distally through the valve 130 (e.g., via the proximal opening 332b) and extend completely through the lumen 124 past the distal end 126b of the catheter 120 such that the tip 246 of the dilator 240 is positioned beyond the distal end 126b of the catheter 120. The notches 250 can be configured to control the position of the dilator 240 relative to the catheter 120, for example, during insertion. For example, when the dilator 240 is inserted (e.g., distally) into the catheter 120 through the valve 130, the notches 250 can couple (e.g., releasably couple) with the tether 336, thereby creating a resistance or interference fit that at least inhibits or prevents further movement (e.g., proximal and / or distal movement) of the dilator 240 relative to the catheter 120. The amount of resistance / interference fit between the notch 250 and the valve 130 (e.g., tether 336) is determined by a third diameter D c and a first diameter D of the first body region 244a. a and / or the second diameter D of the second body region 244b. b 20. The size difference between the diameter of the body region of the expander 240 and another diameter of the expander 240 can be accommodated.

[0032] Generally, the third diameter D c and a diameter of a body region positioned proximally adjacent to the notch 250 (e.g., a first diameter D of the first body region 244a). a ) can be associated with a resistance / interference fit that inhibits or prevents further distal movement of the expander 240 through the system 100 (e.g., through the catheter 120) and / or further proximal movement of the system 100 on the expander 240. Additionally, a third diameter D c and a diameter of a body region positioned distally adjacent to the notch 250 (e.g., a second diameter D of the second body region 244b). b The size difference between the third diameter D ) can be associated with a resistance / interference fit that inhibits or prevents further proximal movement of the expander 240 through the system 100 and / or further distal movement of the system 100 on the expander 240. For example, the third diameter D cand the first diameter D a If the difference between the third diameter D and the notch 250 is about 0.1 mm to about 0.5 mm, the resistance / interference fit may be relatively slight and may partially prevent further (distal) movement of the expander 240 and / or further (proximal) movement of the system 100. In such embodiments, the resistance / interference fit may provide a tactile indication or sensation associated with the relative positions of the expander 240 and the system 100 (e.g., a "click" sound or sensation perceptible to the user), and any resistance / interference to further movement may be overcome by applying increased force to the expander 240 and / or the system 100 to separate the notch 250 and the valve 130 (e.g., tether 336). As another example, c and the first diameter D a If the difference between the third diameter D and the third diameter D is greater than 0.5 mm, the resistance / interference fit may be relatively large and may completely prevent further (distal) movement of the dilator 240 and / or further (proximal) movement of the system 100. In such embodiments, the resistance / interference fit may be overcome by actuating one or more of the buttons 338 of the valve 130 to release the dilator 240. A dilator having a larger diameter may have a greater depth (e.g., a third diameter D) than a dilator having a relatively smaller depth. c and the first and / or second diameter D a , D b and ), where the larger notch depth is expected to provide increased resistance / interference fit than a smaller notch depth.

[0033] In some embodiments, the magnitude of the resistance force / interference fit is based at least in part on the spring force applied to the expander 240 by the valve 130 (e.g., via springs 339a-b). For example, a spring having a relatively high spring constant is expected to provide a greater resistance force than a spring having a relatively low spring constant.

[0034] With the dilator 240 positioned within the catheter 120, the dilator 240 and the catheter 120 may be inserted together into a patient (e.g., a human patient) during a clot treatment procedure. For example, the dilator 240 and the catheter 120 may be inserted into a patient's blood vessel and advanced together through the patient's blood vessel to a target location within the vessel. In some embodiments, after the dilator 240 is inserted through the catheter 120, the dilator 240 and the catheter 120 may move relative to one another so that the catheter 120 may be advanced (e.g., distally, telescopically) over the dilator 240, for example, using the dilator 240 as a guide or "rail" to position the catheter 120 at or near the target location. With the catheter 120 positioned at or near the target location, the dilator 240 may be retracted (e.g., proximally) through the catheter 120 to allow other intravascular medical devices to be introduced into the patient via the catheter 120 and / or the catheter 120 to be aspirated.

[0035] In some aspects of the present technology, the uniform diameter and varying stiffness of the dilator 240 is expected to improve the control and advancement characteristics of the dilator 240 and the catheter 120. For example, the uniform diameter of the dilator 240 is expected to better match the inner diameter of the lumen 124 of the catheter 120, which in turn can reduce or eliminate gaps or spacing between the dilator 240 and the catheter 120. Reducing / eliminating these gaps can at least partially inhibit or prevent the dilator 240 from flexing or bending within the catheter 120 when navigating through the patient's vasculature, which can improve control of the dilator's movement during a procedure. Additionally or alternatively, the uniform diameter of the dilator 240 is expected to improve the durability (e.g., crush resistance) of the catheter 120 when the dilator 240 is positioned within the catheter 120. For example, reducing / eliminating the gap may also be associated with a gap or spacing between the dilator 240 and the catheter 120, reducing the size of, or completely eliminating, one or more crush zones where the catheter 120 may be crushed or bent during use. Additionally, the variable mechanical properties of the dilator body regions 244a-b may improve the flexibility of the dilator and / or its response to forces exerted on the dilator 240 (e.g., by a practitioner and / or from the catheter 120) during a procedure. In these and other embodiments, the notches 250 are expected to further improve the control and advancement characteristics of the dilator 240 and / or the system 100. For example, the amount of resistance / interference fit between the notches 250 and the valve 130 (e.g., tether 336) may be configured to inhibit or prevent overinsertion of the dilator 240, which may damage the patient's vasculature. Additionally or alternatively, the tactile feedback or sensation provided by the interference fit between the notch 250 and the valve 130 can provide (e.g., to a user) an indication of the relative position of the expander 240 within the system 100.

[0036] 4A and 4B are perspective views of a dilator 240 positioned in a system 100, according to an embodiment of the present technology. More specifically, FIG. 4A shows the dilator 240 in a first position or state 401a, and FIG. 4B shows the dilator 240 in a second position or state 401b. In FIGS. 4A and 4B, the coupling component 248 of the dilator 240 includes one or more luer coupling features 452 (individually identified as a first luer coupling feature 452a and a second luer coupling feature 452b in FIGS. 4A and 4B) and / or one or more stop features 454 (individually identified as a first stop feature 454a and a second stop feature 454b). Individual ones of the stop features 454 may be spaced apart from and / or positioned proximally from one or more of the luer coupling features 452.

[0037] With reference to FIG. 4A, the dilator 240 can be inserted through the system 100 until the dilator 240 is coupled to the valve 130 via the notch 250 (FIGS. 2A-3B), as previously described herein with reference to FIGS. 3A and 3B. With the dilator 240 and system 100 in the first position 401a, a first length L1 of the dilator 240 can extend distally beyond the distal end 126b of the catheter 120. In the illustrated embodiment, the first length L1 includes the tip 246 and a portion of the body 242. Additionally or alternatively, the first length L1 can extend from about 1 cm to about 5 cm beyond the distal end 126b. In the first state 401a, the expander 240 and catheter 120 may be in a "standard" or "vascular access" mode or configuration in which the catheter 120 and expander 240 may be inserted into and / or used to navigate through the patient's vasculature, e.g., to a target location, as previously described herein. The expander 240 may then be removed from the catheter 120 such that the system 100 may be used to treat and / or remove clot material from within the patient's body.

[0038] 4B, the dilator 240 can be advanced from the first state 401a to the second state 401b by advancing the dilator 240 distally through the system 100 and / or retracting the system 100 proximally over the dilator 240. In the second state 401b, a second length L2 of the dilator 240 can extend distally beyond the distal terminus 126b. The second length L2 can be greater than the first length L1. In at least some embodiments, for example, the second length L2 is between about 5 cm and about 20 cm, e.g., at least 15 cm, or another suitable length therebetween. In the second state 401b, the expander 240 and catheter 120 may be in a "rail" or "telescopic delivery" mode or configuration, and the catheter 120 may be advanced into and / or through the patient's vasculature while sliding and / or otherwise moving (e.g., telescopically over) the expander 240. In at least some embodiments, telescopically inserting the catheter 120 over the expander 240 may include moving from the second state 401b to and / or toward the first state 401a (FIG. 4A). In these and other embodiments, once the expander 240 and / or catheter 120 are positioned at or near the target location, the expander 240 may then be removed from the catheter 120 such that the system 100 may be used to treat and / or remove clot material from within the patient.

[0039] In some embodiments, one or more of the luer coupling features 452 (FIG. 4A) can be coupled to the valve 130 in the second state 401b, for example, to at least partially or completely prevent further movement (e.g., unintended movement) of the catheter 120 and / or the dilator 240 relative to one another. Additionally or alternatively, one or more of the stop features 454 can contact or abut the valve 130 in the second state 401b, thereby blocking or preventing (i) further distal movement of the dilator 240 relative to the system 100, and / or (ii) further proximal movement of the system 100 relative to the dilator 240.

[0040] As described in detail above, the dilator 240 can include two or more notches (including, for example, the second notch 350 shown in FIGS. 3A and 3B). Each of the notches can be spaced apart along the length of the dilator 240 such that each notch can be associated with a different position of the dilator 240 relative to the system 100 and / or a different length of the dilator 240 that extends beyond the distal end 126b (e.g., between a first length L1 and a second length L2) when coupled through the valve 130. For example, referring together to FIGS. 3A-4B, the second notch 350 is positioned proximal to the first notch 250 such that when the valve 130 is coupled (e.g., locked) to the dilator 240 at the second notch 350, the dilator extends further beyond the distal end 126b of the catheter 120.

[0041] Because each notch can inhibit further movement of the dilator 240 and / or system 100 relative to one another, the location of one or more of the notches can be configured to inhibit or prevent overinsertion of the dilator 240 and / or provide the user with increased control over the amount of the dilator 240 that extends beyond the distal end 126b. Additionally, when the dilator 240 includes multiple notches, the dilator 240 can be configured to transition between more than the two states 401a-b shown in the illustrated embodiment. For example, the dilator 240 can be configured to transition between at least three, four, five, or more different states. EXAMPLES

[0042] Several aspects of the present technology are described in the following examples. 1. An expander comprising: A tip portion, A binding component; a first body region between the tip and the coupling component, the first body region having a first flexibility profile; a second body region between the first body region and the tip, the second body region having a second flexibility profile that is greater than the first flexibility profile; The first body region and the second body region have the same diameter. 2. The expander of example 1, wherein the first body region has a first stiffness and the second body region has a second stiffness, the first stiffness being greater than the second stiffness. 3. The expander of example 1 or example 2, wherein the first body region has a first durometer and the second body region has a second durometer, the second durometer being less than the first durometer. 4. The expander of any of Examples 1-3, wherein the first body region comprises a first material and the second body region comprises a second material different from the first material. 5. The expander of any of Examples 1 to 4, further comprising a third body region between the tip and the coupling component, the third body region having a third flexibility profile different from the first flexibility profile or the second flexibility profile. 6. The expander of any of Examples 1-5, further comprising a notch positioned between the tip and the coupling component. 7. The expander of example 6, wherein the notch is positioned between the first body region and the second body region. 8. The expander of example 6 or example 7, wherein the notch is a first notch and the expander further comprises a second notch positioned proximal or distal to the first notch. 9. A vascular access system comprising: a valve having a proximal end and a distal end; a catheter defining a lumen and coupled to the valve; A dilator configured to be positioned within a lumen through a valve, the dilator comprising: a first body region having a first flexibility profile; and a second body region having a second flexibility profile that is smaller than the first flexibility profile; A vascular access system comprising: a dilator, the first body region and the second body region having the same diameter. 10. The vascular access system of example 8, wherein the first body region has a first stiffness and the second body region has a second stiffness, the first stiffness being greater than the second stiffness. 11. The expander of example 9 or example 10, wherein the first body region has a first durometer and the second body region has a second durometer, the second durometer being less than the first durometer. 12. The vascular access system of any of Examples 9-11, wherein the first body region comprises a first material and the second body region comprises a second material different from the first material. 13. A vascular access system described in any of Examples 9 to 12, wherein the expander further comprises a notch configured to extend at least partially around a longitudinal axis of the expander, and the valve is configured to be releasably coupled to the expander via the notch. 14. The vascular access system of example 13, wherein the notch defines a recessed region of the expander having a notch diameter smaller than the diameters of the first body region and the second body region. 15. A vascular access system as described in Example 13 or Example 14, wherein the valve includes a tether, the tether configured to be positioned at least partially within the notch to releasably couple the expander to the valve. 16. The vascular access system of Example 15, wherein the tether is biased in a first direction to releasably couple the expander to the valve, and the valve further comprises a button operably coupled to the tether and configured to move the tether in a second direction opposite the first direction to cause the tether to uncouple the expander from the valve. 17. A vascular access system described in any of Examples 13 to 16, wherein the notch is a first notch and the expander further includes a second notch positioned proximal or distal to the notch. 18. The vascular access system of Example 17, wherein the catheter includes a distal end, a first length of the expander extends beyond the distal end when the first notch is coupled to the valve, and a second length of the expander extends beyond the distal end when the second notch is coupled to the valve. 19. The vascular access system of example 18, wherein the second length is greater than the first length. 20. A method of treating clot material in a patient, the method comprising: positioning a dilator within the vascular access system such that a valve of the vascular access system releasably engages a notch in the dilator to prevent further movement of the dilator relative to the vascular access system; actuating a button on the valve to release the notch from the valve to allow further movement of the dilator relative to the vascular access system; The method includes moving a dilator relative to the vascular access system and / or moving the vascular access system relative to the dilator. 21. The method of example 20, wherein moving the dilator relative to the vascular access system includes advancing the dilator through the vascular access system to increase a length of the dilator extending beyond the distal end of the vascular access system. 22. The method of example 20, wherein moving the vascular access system relative to the dilator includes advancing the vascular access system over the dilator to reduce a length of the dilator extending beyond the distal end of the vascular access system. 23. The notch is a first notch, and the method comprises: positioning a dilator within the vascular access system such that the valve releasably engages the second notch of the dilator; The method of any of Examples 20-22, further comprising applying a force to the expander and / or vascular access system to release the second notch from the valve. 24. The method of example 23, wherein applying a force to release the second notch from the valve includes applying a force to release the second notch from the valve without actuating a button. 25. A vascular access system comprising: a dilator extending along a longitudinal axis, the dilator having a flexibility profile that varies at least partially along the longitudinal axis, the dilator defining a notch that extends at least partially circumferentially about the longitudinal axis; a valve having a proximal end and a distal end; a catheter coupled to the valve and defining a lumen; A vascular access system, wherein the valve is configured to be releasably coupled to the expander via the notch to prevent movement of the expander relative to the catheter when at least a portion of the expander is inserted into the lumen of the catheter through the valve. 26. The vascular access system of example 25, wherein the expander includes a body region having a diameter, and the notch includes a recessed region of the expander having a notch diameter smaller than the diameter of the body region. 27. A vascular access system as described in Example 25 or Example 26, wherein the valve includes a tether, the tether configured to be positioned at least partially within the notch to releasably couple the expander to the valve. 28. The vascular access system of Example 27, wherein the tether is biased in a first direction to releasably couple the expander to the valve, and the valve is operably coupled to the tether, and further comprises a button configured to move the tether in a second direction opposite the first direction to move the tether at least partially out of the notch to uncouple the expander from the valve. 29. A vascular access system as described in any of Examples 25-28, wherein the notch is a first notch, a portion of the dilator is the first portion, the dilator further defines a second notch extending at least partially circumferentially about the longitudinal axis, and the valve is configured to be releasably coupled to the dilator via the second notch to prevent movement of the dilator relative to the catheter when at least the second portion of the dilator is inserted through the valve and into the lumen of the catheter. 30. The vascular access system of Example 29, wherein the catheter includes a distal end, a first length of the expander extends beyond the distal end when the first notch is coupled to the valve, and a second length of the expander extends beyond the distal end when the second notch is coupled to the valve. 31. The vascular access system of example 30, wherein the second length is greater than the first length. 32. A vascular access system described in any of Examples 25-31, wherein the expander includes a proximal body region having a first flexibility profile and a distal body region having a second flexibility profile greater than the first flexibility profile, and the notch is positioned at least partially between the proximal body region and the distal body region. 33. The vascular access system of claim 25, wherein the dilator has a durometer that varies at least partially along the longitudinal axis.

[0043] The above detailed description of the embodiments of the present technology is not intended to be exhaustive or to limit the present technology to the precise form disclosed above. Although specific embodiments and examples of the present technology are described above for illustrative purposes, those skilled in the art will recognize that various equivalent modifications are possible within the scope of the present technology. For example, while steps are presented in a given order, alternative embodiments may perform steps in a different order. Various embodiments described herein may also be combined to provide further embodiments.

[0044] From the above, it will be understood that, although specific embodiments of the present technology are described herein for illustrative purposes, well-known structures and functions have not been shown or described in detail to avoid unnecessarily obscuring the description of the embodiments of the present technology. Where permitted by context, singular or plural terms may also include the plural or singular terms, respectively.

[0045] Further, unless the term "or" is expressly limited to mean only a single item in relation to a list of two or more items, the use of "or" in such a list should be interpreted as including (a) any single item in the list, (b) all of the items in the list, or (c) any combination of the items in the list. Additionally, the term "comprising" is used throughout to mean the inclusion of at least the recited features, without excluding any more of the same features and / or other features of additional types. Although specific embodiments have been described herein for illustrative purposes, it will also be understood that various modifications may be made without departing from the technology. Furthermore, although advantages associated with some embodiments of the technology have been described in the context of these embodiments, other embodiments may also exhibit such advantages, and not all embodiments necessarily exhibit such advantages to fall within the scope of the technology. Thus, the present disclosure and related technology may encompass other embodiments not expressly shown or described herein.

Claims

1. It is an expander, The tip and, Connecting components and, A first body region between the tip portion and the coupling component, wherein the first body region has a first flexible profile, A second body region between the first body region and the tip portion, wherein the second body region has a second flexible profile that is larger than the first flexible profile, An expander in which the first body region and the second body region have the same diameter.

2. The expander according to claim 1, wherein the first body region has a first rigidity, the second body region has a second rigidity, and the first rigidity is greater than the second rigidity.

3. The expander according to claim 1, wherein the first body region has a first durometer, and the second body region has a second durometer, the second durometer being smaller than the first durometer.

4. The expander according to claim 1, wherein the first body region includes a first material, and the second body region includes a second material different from the first material.

5. The expander according to claim 1, further comprising a third body region between the tip portion and the coupling component, wherein the third body region has a third flexible profile different from the first flexible profile or the second flexible profile.

6. The expander according to claim 1, further comprising a notch positioned between the tip and the coupling component.

7. The expander according to claim 6, wherein the notch is positioned between the first body region and the second body region.

8. The expander according to claim 6, wherein the notch is a first notch, and the expander further comprises a second notch positioned proximal or distal to the first notch.

9. A vascular access system, A valve having a proximal end and a distal end, A catheter is used to define the lumen and connect to the valve, An expander configured to be positioned within the lumen through the valve, wherein the expander is A first body region having a first flexible profile, and It includes a second body region having a second flexible profile smaller than the first flexible profile, A vascular access system comprising a dilator having a first main body region and a second main body region having the same diameter.

10. The vascular access system according to claim 9, wherein the first main body region has a first rigidity, the second main body region has a second rigidity, and the first rigidity is greater than the second rigidity.

11. The vascular access system according to claim 9, wherein the first main body region has a first durometer, and the second main body region has a second durometer, the second durometer being smaller than the first durometer.

12. The vascular access system according to claim 9, wherein the first main body region comprises a first material, and the second main body region comprises a second material different from the first material.

13. The vascular access system according to claim 9, wherein the dilator further includes a notch configured to extend at least partially around the longitudinal axis of the dilator, and the valve is configured to be releasably coupled to the dilator via the notch.

14. The vascular access system according to claim 13, wherein the notch defines a recessed region of the expander having a notch diameter smaller than the diameter of the first main body region and the second main body region.

15. The vascular access system according to claim 13, wherein the valve includes a tether, the tether is configured to be at least partially positioned within the notch in order to releasably connect the dilator to the valve.

16. The vascular access system according to claim 15, wherein the tether is biased in a first direction to releasably couple the dilator to the valve, and the valve further comprises a button operably coupled to the tether, the button being configured to move the tether in a second direction opposite to the first direction, thereby discouple the dilator from the valve to the tether.

17. The vascular access system according to claim 13, wherein the notch is a first notch, and the dilator further includes a second notch positioned proximal or distal to the notch.

18. The vascular access system according to claim 17, wherein the catheter includes a distal end, the first length of the dilator extends beyond the distal end when the first notch is connected to the valve, and the second length of the dilator extends beyond the distal end when the second notch is connected to the valve.

19. The vascular access system according to claim 18, wherein the second length is greater than the first length.

20. A vascular access system, A valve including a button, A dilator including a notch, wherein the dilator is configured to be positioned within the vascular access system such that the valve releasably engages with the notch of the dilator to prevent further movement of the dilator relative to the vascular access system, A vascular access system wherein the operation of the button on the valve releases the notch from the valve, allowing further movement of the dilator relative to the vascular access system, so that the dilator is movable relative to the vascular access system and / or the vascular access system is movable relative to the dilator.

21. The vascular access system according to claim 20, wherein, when the dilator is movable relative to the vascular access system, the dilator is further configured to be advanced through the vascular access system to increase the length of the dilator extending beyond the distal end of the vascular access system.

22. The vascular access system according to claim 20, wherein when the vascular access system is movable relative to the dilator, the vascular access system is configured to be advanced on the dilator in order to reduce the length of the dilator that extends beyond the distal end of the vascular access system.

23. The aforementioned notch is a first notch, and the expander further includes a second notch. The expander is further configured to be positioned within the vascular access system such that the valve releasably engages with the second notch of the expander. The vascular access system according to claim 20, wherein a force is applied to the expander and / or the vascular access system to release the second notch from the valve.

24. The vascular access system according to claim 23, wherein the force is applied to release the second notch from the valve without activating the button.

25. A vascular access system, An expander extending along a longitudinal axis, wherein the expander has at least partially a variable flexible profile along the longitudinal axis, and the expander defines a notch that at least partially extends circumferentially around the longitudinal axis, A valve having a proximal end and a distal end, The valve is connected to a catheter that defines the lumen, A vascular access system wherein the valve is configured to be releasably coupled to the dilator via a notch to prevent the dilator from moving relative to the catheter when at least a portion of the dilator is inserted into the lumen of the catheter through the valve.

26. The vascular access system according to claim 25, wherein the expander includes a main body region having a diameter, and the notch includes a recessed region of the expander having a notch diameter smaller than the diameter of the main body region.

27. The vascular access system according to claim 25, wherein the valve includes a tether, the tether is configured to be at least partially positioned within the notch in order to releasably connect the dilator to the valve.

28. The vascular access system according to claim 27, wherein the tether is biased in a first direction to releasably couple the dilator to the valve, and the valve further comprises a button operably coupled to the tether, the button being configured to move the tether in a second direction opposite to the first direction to release the dilator from the valve, thereby moving the tether at least partially out of the notch.

29. The vascular access system according to claim 25, wherein the notch is a first notch, the portion of the dilator is a first portion, the dilator further defines a second notch that extends at least partially circumferentially around the longitudinal axis, and the valve is configured to be releasably coupled to the dilator via the second notch to prevent the dilator from moving relative to the catheter when at least the second portion of the dilator is inserted into the lumen of the catheter through the valve.

30. The vascular access system according to claim 29, wherein the catheter includes a distal end, the first length of the dilator extends beyond the distal end when the first notch is coupled to the valve, and the second length of the dilator extends beyond the distal end when the second notch is coupled to the valve.

31. The vascular access system according to claim 30, wherein the second length is greater than the first length.

32. The vascular access system according to claim 25, wherein the expander includes a proximal body region having a first flexible profile and a distal body region having a second flexible profile larger than the first flexible profile, and the notch is positioned at least partially between the proximal body region and the distal body region.

33. The vascular access system according to claim 25, wherein the expander has a durometer that varies at least partially along the longitudinal axis.

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