Catheters with multiple coil layers and related systems and methods

Abstract

Disclosed herein are catheters having multiple coil layers, as well as related systems and methods. In some embodiments, the catheter includes an inner liner, multiple wires covering the inner liner, and an outer sheath covering the wires. The wires are coiled in a first direction around the longitudinal axis of the catheter to form a first coil layer on the inner liner, and the wires are coiled in a second direction opposite the first direction around the longitudinal axis over the first coil layer to form a second coil layer on the first coil layer. The wires each include a continuous / self-terminating end where the wires switch from the first direction to the second direction and transition from the inner coil layer to the outer coil layer.

Description

[Technical Field]

[0001] (CROSS-REFERENCE TO RELATED APPLICATIONS) This application claims the benefit of U.S. Provisional Patent Application No. 63 / 405,251, filed September 9, 2022, and entitled "CATHETERS HAVING MULTIPLE COIL LAYERS, AND ASSOCIATED SYSTEMS AND METHODS," which is incorporated herein by reference in its entirety.

[0002] The present technology relates generally to catheters having multiple coil layers, and more particularly to catheters having adjacent coil layers formed from the same wire that are (i) coiled in a first direction to form an inner coil layer and (ii) coiled in a second direction opposite the first direction to form an outer coil layer over the inner coil layer. [Background technology]

[0003] Thromboembolism is characterized by the blockage of blood vessels. Thromboembolic disorders, such as stroke, pulmonary embolism, heart attack, peripheral thrombosis, and atherosclerosis, affect many people. These diseases are major causes of morbidity and mortality.

[0004] When an artery is occluded by a clot, tissue ischemia develops. Ischemia progresses to tissue infarction if the occlusion persists. If blood flow is rapidly restored, infarction may not occur or may be severely limited. Failure to restore blood flow can lead to limb loss, angina, myocardial infarction, stroke, and even death.

[0005] In the venous circulation, obstructive material can also cause serious harm. Blood clots can develop in the large veins of the legs and pelvis, a common condition known as deep venous thrombosis (DVT). DVT typically occurs in situations prone to blood pooling (e.g., long-distance air travel, immobility, etc.) and blood clots (e.g., cancer, recent surgery such as orthopedic surgery, etc.). DVT causes harm by (1) blocking venous blood drainage from the legs, resulting in swelling, ulcers, pain, and infection, and (2) acting as a reservoir for blood clots that travel to other parts of the body, including the heart, lungs, brain (stroke), abdominal organs, and / or limbs.

[0006] In the pulmonary circulation, unwanted substances can cause harm by obstructing the pulmonary arteries (a condition known as pulmonary embolism). If the obstruction is upstream in the main or major pulmonary artery bifurcation, it can significantly impair total blood flow within the lungs and therefore the entire body, resulting in hypotension and shock. If the obstruction is downstream from the major pulmonary artery bifurcation in the middle pulmonary artery bifurcation, it can prevent a significant portion of the lung from participating in gas exchange with the blood, resulting in low blood oxygen and a buildup of blood carbon dioxide.

[0007] Many existing techniques exist for restoring blood flow through blocked blood vessels. One common surgical technique, embolectomy, involves incising the vessel and introducing a balloon-tipped device (such as a Fogarty catheter) to the site of the blockage. The balloon is then inflated beyond the clot and used to push the obstructing material back up to the incision point. The obstructing material is then removed by the surgeon. While such surgical techniques are useful, exposing the patient to surgery can be traumatic and is best avoided if possible. Furthermore, the use of a Fogarty catheter can be problematic due to the risk of potentially damaging the vessel's inner wall as the catheter is withdrawn.

[0008] Percutaneous methods are also utilized to restore blood flow. A common percutaneous technique is called balloon angioplasty, in which a balloon-tipped catheter is introduced into a blood vessel (e.g., typically through an introducer catheter). The balloon-tipped catheter is then advanced to the point of occlusion and inflated to dilate the stenosis. While balloon angioplasty is suitable for treating vascular stenosis, it is generally ineffective for treating acute thromboembolic events because the occlusive material is not completely removed and the vessel may restenose after dilation. Another percutaneous technique involves placing a catheter near the clot and injecting streptokinase, urokinase, or other thrombolytic agents to dissolve the clot. Unfortunately, thrombolysis typically takes hours to days to be successful. Furthermore, thrombolytic agents can cause bleeding, and many patients cannot use thrombolytic agents at all.

[0009] Various devices exist for performing thrombectomy or removing other foreign bodies. However, such devices have been found to have structures that are either overly complex, cause trauma to the treated vessel, or lack sufficient retention structures, resulting in an inability to properly secure against the vessel and underperforming. Furthermore, many of the devices have highly complex structures that lead to difficulties in manufacturing and quality control, as well as delivery problems when passing through tortuous or small-diameter catheters. While less complex devices may allow users, especially inexperienced users, to clear through the clot, such devices may not completely capture and / or collect all of the clot material. Summary of the Invention [Means for solving the problem]

[0010] The present technology generally relates to catheters (e.g., aspiration catheters) having multiple coil layers, as well as related systems and methods. In some embodiments, a catheter configured in accordance with the present technology includes an inner liner, multiple wires covering the inner liner, and an outer sheath covering the wires. The wires are coiled in a first direction around a longitudinal axis of the catheter to form a first coil layer on the inner liner, and the wires are coiled in a second direction opposite the first direction around the longitudinal axis over the first coil layer to form a second coil layer on the first coil layer. The wires each include a continuous / self-terminating end where the wires switch from the first direction to the second direction and transition from the inner coil layer to the outer coil layer.

[0011] In some aspects of the present technology, the inner and outer coil layers may be configured to provide a catheter with selected properties (e.g., selected flexibility, pushability, torque, kink resistance, hoop strength, and / or other properties known in the catheter art) along the entire length of the catheter or in selected regions of the catheter. For example, the number of wires used to form the inner and outer coil layers and / or the pitch between the wires may be varied.

[0012] In a further aspect of the present technology, the arrangement of the inner and outer coil layers can enable the catheter to be steered and positioned in difficult-to-reach (e.g., tortuous) areas of a patient's anatomy (e.g., venous anatomy) while still having a relatively large size (e.g., 20 French, 24 French, greater than 24 French). More specifically, the inner and outer coil layers can provide the catheter with torqueability and pushability similar to that of conventional catheters including braided structures (e.g., braided mesh). Similarly, the inner and outer coil layers can provide hoop strength and flexibility similar to or greater than that of conventional catheters including solid-wire coil structures, while also reducing kinking around tight bend radii. Furthermore, the inner and outer coil layers enable the catheter to have these properties without including a braided structure or other reinforcing structure, which allows the catheter to be manufactured with a relatively thinner inner liner and / or outer sheath, resulting in a catheter with a thinner wall. This allows the inner diameter of the catheter to be larger than other catheters labeled with the same outer diameter French size. A larger inner diameter may be optimal for generating aspiration flow (eg, increasing aspiration flow) during thrombectomy or embolectomy, resulting in more complete clot removal. [Brief explanation of the drawings]

[0013] 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.

[0014] [Figure 1] 1 is a partially schematic side view of a clot treatment system including a catheter in accordance with an embodiment of the present technology; [Figure 2] 2 is a cross-sectional side view of the catheter of FIG. 1 taken along line CC in FIG. 1 in accordance with an embodiment of the present technology. [Figure 3A] FIG. 2 is an enlarged isometric view of a portion of the catheter of FIG. 1 in accordance with an embodiment of the present technology. [Figure 3B]FIG. 2 is an enlarged isometric view of a portion of the catheter of FIG. 1 in accordance with an embodiment of the present technology. [Figure 3C] FIG. 2 is a side view of the inner and outer coil layers of the catheter of FIG. 1 at a distal portion of the catheter in accordance with an embodiment of the present technology. [Figure 3D] FIG. 2 is a side view of the inner and outer coil layers of the catheter of FIG. 1 at a distal portion of the catheter in accordance with an embodiment of the present technology. [Figure 3E] FIG. 2 is a side view of the inner and outer coil layers of the catheter of FIG. 1 at a distal portion of the catheter in accordance with an embodiment of the present technology. [Figure 3F] FIG. 2 is a side view of the inner and outer coil layers of the catheter of FIG. 1 at a distal portion of the catheter in accordance with an embodiment of the present technology. [Figure 3G] FIG. 2 is a side view of the inner and outer coil layers of the catheter of FIG. 1 at a distal portion of the catheter in accordance with an embodiment of the present technology. [Figure 4] FIG. 2 is an enlarged isometric view of a portion of the catheter of FIG. 1 in accordance with an additional embodiment of the present technology. [Figure 5] FIG. 2 is an enlarged isometric view of a portion of the catheter of FIG. 1 in accordance with an additional embodiment of the present technology. [Figure 6] FIG. 2 is a cross-sectional side view of the catheter of FIG. 1 taken along line CC of FIG. 1 in accordance with an additional embodiment of the present technology. [Figure 7] FIG. 2 is a cross-sectional side view of the catheter of FIG. 1 taken along line CC of FIG. 1 in accordance with an additional embodiment of the present technology. [Figure 8] FIG. 2 is a cross-sectional side view of the catheter of FIG. 1 taken along line CC of FIG. 1 in accordance with an additional embodiment of the present technology. [Figure 9] FIG. 2 is a flow diagram of a process or method for manufacturing the catheter of FIG. 1 in accordance with an embodiment of the present technology. [Figure 10A] 2 is a side view of the distal portion of the catheter of FIG. 1 during a procedure to remove clotting material from within a patient's blood vessel BV in accordance with an embodiment of the present technology. [Figure 10B] 2 is a side view of the distal portion of the catheter of FIG. 1 during a procedure to remove clotting material from within a patient's blood vessel BV in accordance with an embodiment of the present technology. DETAILED DESCRIPTION OF THE INVENTION

[0015] Specific details are set forth in the following description and in FIGS. 1-10B 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. Furthermore, while reference is made primarily to aspiration catheters and catheters for use in clot removal procedures, the catheters of the present technology may be other types of catheters and / or may be used in other types of medical procedures. However, one skilled in the art will recognize that the present technology may be practiced without one or more of the details described herein and / or with other structures, methods, components, and the like.

[0016] 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 will be expressly and specifically defined as such in this detailed description section.

[0017] The accompanying drawings depict embodiments of the present technology and are not intended to limit its scope unless explicitly stated. The sizes of various depicted elements are not necessarily drawn to scale, and these various elements may be enlarged to improve readability. 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 make and use the present technology. Many of the details, dimensions, angles, and other features shown in the figures are merely illustrative of particular embodiments of the present disclosure. Thus, other embodiments can have other details, dimensions, angles, and features without departing from the present technology. Additionally, those skilled in the art will understand that further embodiments of the present technology can be practiced without some of the details described below.

[0018] With respect to the terms "distal" and "proximal" herein, unless otherwise specified, these terms may refer to the relative position of portions of a catheter subsystem relative to an operator and / or a location within the vasculature. Also, as used herein, designations such as "rear," "forward," "superior," "inferior," 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.

[0019] As used herein, unless expressly indicated otherwise, terms such as "about," "approximately," and "substantially" mean within ±10% of the stated value. To the extent that materials incorporated herein by reference conflict with the present disclosure, the present disclosure controls. The headings provided herein are for convenience only and should not be construed as limiting the disclosed subject matter. I. SELECTED EMBODIMENTS OF THE CLOMATIC TREATMENT SYSTEM

[0020] 1 is a partially schematic side view of a clot treatment system 100 in accordance with an embodiment of the present technology. The clot treatment system 100 may also be referred to as an aspiration assembly, a clot removal system, and / or a thrombectomy system. In the illustrated embodiment, the clot treatment system 100 includes a tubing assembly 110 fluidly connected to a catheter 120 via a valve 102. In general, the clot treatment system 100 (i) may include features generally similar or identical to those described in detail in U.S. Patent Application No. 16 / 636,185, entitled "SYSTEM FOR TREATING EMBOLISM AND ASSOCIATED DEVICES AND METHODS," filed August 8, 2019, and 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 described in detail therein.

[0021] In the illustrated embodiment, catheter 120 includes (i) a proximal region or portion 122, (ii) an intermediate region 124 adjacent to and distal to proximal region 122, (iii) a distal region 126 adjacent to and distal to intermediate region 124, and (iv) a distal tip region 128 adjacent to and distal to distal region 126 (collectively “regions 122, 124, 126, 128”). Catheter 120 further defines a lumen 121 extending completely therethrough from proximal region 122 to distal tip region 128. Proximal region 122 defines a proximal terminus 123 of catheter 120, and distal tip region 128 defines a distal terminus 125 of catheter 120. In the illustrated embodiment, the distal tip region 128 includes a marker band 129, such as a radiopaque marker, configured to facilitate visualization of the position of the catheter 120 during a medical procedure (e.g., a clot removal procedure) using the catheter 120. In other embodiments, the marker band 129 may be omitted or positioned at a different location along the catheter 120, and / or the catheter 120 may include additional marker bands to facilitate visualization of the catheter 120.

[0022] In some embodiments, proximal region 122 has a first length, intermediate region 124 has a second length that is shorter than the first length, distal region 126 has a third length that is longer than the second length but shorter than the first length, and distal tip region 128 has a fourth length that is shorter than the first, second, and third lengths. For example, the first length can be approximately 20.00 to 50.00 inches (e.g., approximately 22.0 inches), the second length can be approximately 2.0 to 3.0 inches (e.g., approximately 2.50 inches), the third length can be approximately 10.00 to 20.00 inches (e.g., approximately 16.00 inches), and the fourth length can be approximately 0.10 to 0.50 inches (e.g., approximately 0.15 inches). In other embodiments, the lengths of one or more of regions 122, 124, 126, 128 can be different. As used herein with respect to the first through fourth lengths, the term "about" means within ±0.50 inches of the stated length. In some embodiments, catheter 120 can have different flexibility, shape, thickness, and / or other properties at / along various regions 122, 124, 126, 128, as described in more detail below. The lengths of regions 122, 124, 126, 128 relative to one another in the figures may not be drawn to scale.

[0023] Valve 102 is fluidly coupled to lumen 121 of catheter 120 and can be integral with or coupled to a proximal region 122 of catheter 120. In some embodiments, valve 102 is a hemostatic valve configured to maintain hemostasis during a clot removal procedure by blocking or preventing proximal fluid flow through valve 102 as various components, such as a delivery sheath, tensioning member, guidewire, interventional device, or other aspiration catheter, are inserted through valve 102 and delivered to a treatment site in a blood vessel through catheter 120. Valve 102 includes a bifurcation or side port 104 configured to fluidly connect lumen 121 of catheter 120 to tubing assembly 110. In some embodiments, valve 102 can be a valve of the type disclosed in U.S. Patent Application No. 16 / 117,519, filed August 30, 2018, entitled "HEMOSTASIS VALVES AND METHODS OF USE," which is incorporated herein by reference in its entirety.

[0024] In the illustrated embodiment, tubing assembly 110 fluidly couples catheter 120 to pressure source 106, such as a syringe. Tubing assembly 110 can include one or more tubing sections 112 (individually labeled as first tubing section 112a and 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 tubing assembly 110 to pressure source 106 and / or other suitable components. In some embodiments, fluid control device 114 is a stopcock that is fluidly coupled (i) to side port 104 of valve 102 via first tubing section 112a and (ii) to connector 116 via second tubing section 112b. Fluid control device 114 is externally operable by a user to regulate the flow of fluid therethrough, specifically from lumen 121 of catheter 120 to pressure source 106. In some embodiments, connector 116 is a quick-release connector (e.g., a quick-disconnect fitting) that allows for rapid coupling / detachment of catheter 120 and fluid control device 114 to / from pressure source 106. II. SELECTED EMBODIMENTS OF CATHETERS WITH SELF-TERMINATING COILS

[0025] 2 is a side cross-sectional view of catheter 120 taken along line CC in FIG. 1 in accordance with an embodiment of the present technology. In the illustrated embodiment, catheter 120 includes an outer sheath 230 and an inner liner 232 that extend through / define each of regions 122, 124, 126, and 128. Outer sheath 230 is positioned over (e.g., radially outward from) inner liner 232. Outer sheath 230 may also be referred to as an outer jacket, outer shaft, outer layer, etc., and inner liner 232 may also be referred to as an inner layer, inner sheath, inner shaft, etc. In the illustrated embodiment, catheter 120 further includes an inner coil layer 234 (e.g., a first coil layer) and an outer coil layer 236 (e.g., a second coil layer) that extends over / around inner coil layer 234. 3A-3G, the inner coil layer 234 and the outer coil layer 236 (collectively "coil layers 234, 236") may include a plurality of individual wires wound around the inner liner 232. The coil layers 234, 236 may extend along the entire length of the catheter 120 through each of the regions 122, 124, 126, 128, or may extend only partially along the length of the catheter 120 (e.g., in the distal region 126 and the distal tip region 128). The coil layers 234, 236 may be collectively referred to as a reinforcing structure or the like.

[0026] The outer sheath 230 may be formed from a plastic material, an elastomeric material, and / or a thermoplastic elastomer (TPE) material. In some embodiments, the outer sheath 230 may be formed from a TPE manufactured by Arkema SA (Colombes, France) (e.g., a TPE manufactured under the trade name "Pebax"). In some embodiments, the outer sheath 230 may have various hardnesses (e.g., durometers), thicknesses, flexibility, stiffness, and / or other properties in one or more of the different regions 122, 124, 126, 128. For example, the outer sheath 230 may have a first hardness along the proximal region 122, a second hardness lower than the first hardness along the intermediate region 124, a third hardness lower than the first and second hardnesses along the distal region 126, and a fourth hardness higher than the third hardness at the distal tip region 128. In some embodiments, the first hardness and fourth hardness can each be about 65D to 75D (e.g., about 72D), the second hardness can be about 45D to 60D (e.g., about 45D, about 50D), and the third hardness can be about 25D to 40D (e.g., about 25D, about 30D, about 35D). As used herein with respect to the first through fourth hardnesses, the term "about" means within ±2D of the stated hardness. In other embodiments, one or more of regions 122, 124, 126, 128 can have different hardnesses.

[0027] The inner liner 232 defines the lumen 121 and, in some embodiments, may be formed from a lubricious material that facilitates movement (e.g., distal advancement, proximal retraction) of various components through the lumen 121, such as a delivery sheath, tensioning member, guidewire, interventional device, other aspiration catheter, etc. In some embodiments, the inner liner 232 may be formed from a polymeric material, a fluoropolymer material (e.g., polytetrafluoroethylene (PTFE)), and / or another material with a high degree of lubricity. The inner liner 232 defines the inner diameter D of the catheter 120. The thicknesses of the outer sheath 230, inner liner 232, and coil layers 234, 236 relative to each other and / or relative to the inner diameter D may not be drawn to scale in FIG. 2 . For example, those skilled in the art will understand that catheter 120 can have a relatively thin wall (e.g., including outer sheath 230, inner liner 232, and coil layers 234, 236) compared to inner diameter D, although the thicknesses of these components are shown for clarity. In some embodiments, inner diameter D is greater than about 6 French, greater than about 10 French, greater than about 16 French, greater than about 20 French, greater than about 24 French, or greater. In some embodiments, inner diameter D is about 8 French, about 16 French, about 20 French, about 24 French, or about 26 French. As used herein with respect to inner diameter D, the term "about" means within ±1 French of the stated diameter. In certain embodiments, inner diameter D of inner liner 232 is the same in each of regions 122, 124, 126, and 128, while in other embodiments, inner diameter D can vary along one or more of regions 122, 124, 126, and 128.

[0028] In some embodiments, the inner liner 232 or the outer sheath 230 can be omitted. For example, the inner liner 232 can be omitted, and the coil layers 234, 236 can be bonded (e.g., fused) to the outer sheath 230.

[0029] 3A and 3B are enlarged isometric views of a portion of the catheter 120 shown in FIG. 1 in accordance with an embodiment of the present technology. Specifically, the portion of the catheter 120 shown in FIG. 3A is a portion of the catheter 120 proximal to the distal end 125, and the portion of the catheter shown in FIG. 3B is a portion of the catheter 120 including the distal end 125. The outer sheath 230 (FIG. 2) is not shown in FIGS. 3A and 3B for clarity. FIGS. 3C and 3D are side views of coil layers 234, 236, for example, in the distal region 126 and distal tip region 128 shown in FIG. 1 in accordance with an embodiment of the present technology. Referring together to FIGS. 3A-3D, the coil layers 234, 236 comprise a plurality of individual wires 340 (e.g., filaments, threads, strands, etc., individually identified as a first wire 340a, a second wire 340b, a third wire 340c, and a fourth wire 340d). For clarity, the individual wires 340a, 340b, 340c, and 340d are shown with different patterns / fills in Figure 3C, and the coil layers 234, 236 are shown with different patterns / fills in Figure 3D. Other than the pattern / fills of the wire 340, Figures 3C and 3D are identical.

[0030] In the illustrated embodiment, the wire 340 extends around the inner liner 232 in a helical or spiral pattern in a first direction about the longitudinal axis L (FIG. 1) of the catheter 120 to form the inner coil layer 234, and the wire 340 is folded back at the distal end 342 (FIGS. 3B-3D) to extend around the inner coil layer 234 in a helical or spiral pattern in a second direction about the longitudinal axis L to form the outer coil layer 236. More specifically, in the illustrated embodiment, the wire 340 is (i) wound / coiled around the inner liner 232 in a distal direction D within the inner coil layer 234 so that the helical or spiral pattern of the wire 340 in the inner coil layer 234 has a first orientation (e.g., a left-handed orientation), and (ii) wound / coiled around the inner coil layer 234 in a proximal direction P within the outer coil layer 236 so that the helical or spiral pattern of the wire 340 in the outer coil layer 236 has a second orientation opposite the first orientation (e.g., a right-handed orientation).

[0031] 3B-3D together, the wires 340 each include a distal termination or end 342 where the wires 340 switch direction and transition from the inner coil layer 234 to the outer coil layer 236. Thus, the wires 340 are self-terminating (e.g., continuous) at the distal tip region 128 (FIG. 1) of the catheter 120. In contrast, the proximal and distal ends (not shown) of the wires 340 may individually terminate at the proximal region 122 (FIG. 1) of the catheter 120. In some aspects of the present technology, the wires 340 do not need to be glued, annealed, or otherwise secured together at the distal ends 342 because the distal ends 342 are self-terminating, thereby reducing the cost and complexity of manufacturing the catheter 120.

[0032] Further, each of the wires 340 includes a first portion (e.g., a first half) that is wound around the inner liner 232 to form the inner coil layer 234, and a second portion (e.g., a second half) that is wound around the inner coil layer 234 to form the outer coil layer 236. A distal end 342 of each of the wires 340 separates the first portion from the second portion. In some embodiments, the coil layers 234, 236 are not secured together, e.g., such that the first and second portions of the wire 340 can move relative to one another. Referring together to FIGS. 2-3D , such movement can be limited by the outer sheath 230 and / or the inner liner 232, which can bond / secure the coil layers 234, 236 together. That is, the outer sheath 230 and the inner liner 232 can secure the coil layers 234, 236 in place. In other embodiments, the coil layers 234, 236 are secured directly to one another by adhesive, welding, or the like.

[0033] 3A-3D together, first wire 340a is positioned between (e.g., adjacent to) second wire 340b and fourth wire 340d, second wire 340b is positioned between first wire 340a and third wire 340c, third wire 340c is positioned between second wire 340b and fourth wire 340d, and fourth wire 340d is positioned between third wire 340c and first wire 340a. In the illustrated embodiment, wires 340 are evenly spaced apart from one another by a first pitch P1 within inner coil layer 234, and wires 340 are evenly spaced apart from one another by a second pitch P2 within outer coil layer 236. In some embodiments, first and second pitches P 1~2 may be the same along the entire length of catheter 120. In other embodiments, as described in more detail below, the first and second pitches P 1~2 may differ and / or vary along the length of the catheter 120 to provide different mechanical properties along the length of the catheter 120.

[0034] In the illustrated embodiment, the catheter 120 includes four of the wires 340 forming the coil layers 234, 236. In other embodiments, the catheter 120 can include more or fewer wires 340 (e.g., one wire, two wires, three wires, five wires, six wires, eight wires, twelve wires, or more than twelve wires). The wires 340 can be flat wires (e.g., rolled flat wires) having a generally rectangular cross-sectional shape with dimensions of about 0.001 to 0.005 inches (e.g., about 0.003 inches) by about 0.002 to 0.025 inches (e.g., about 0.010 inches). In other embodiments, the wires 340 can have other cross-sectional shapes (e.g., circular). The wires can be formed from metals or other suitably strong materials, such as nickel-titanium alloys (e.g., nitinol), platinum, cobalt-chromium alloys, stainless steel, tungsten, and / or titanium. In some embodiments, some or all of the wires 340 may comprise a shape memory material that is heat-set or otherwise configured to have a predetermined shape. For example, some or all of the wires may be configured to deflect such that the catheter 120 has pre-shaped portions (e.g., along some or all of the distal region 126 and / or distal tip region 128), as described in U.S. Patent Application No. 17 / 529,018, filed November 17, 2021, entitled "CATHETERS HAVING SHAPED DISTAL PORTIONS, AND ASSOCIATED SYSTEMS AND METHODS," which is incorporated herein by reference in its entirety.

[0035] 3E-3G are additional side views of coil layers 234, 236 in, for example, distal region 126 and distal tip region 128 shown in FIG. 1 , in accordance with an embodiment of the present technology. Other than the pattern / fill of wires 340, FIGS. 3E-3G are identical to FIGS. 3C and 3D. For clarity, FIG. 3E shows inner coil layer 234 with a single pattern / fill and individual first wires 340a-4th wires 340d in outer coil layer 236 with different patterns / fills. That is, a second portion of wires 340 forming outer coil layer 236 is shown with a different pattern / fill. FIG. 3F shows outer coil layer 236 with a single pattern / fill and individual first wires 340a-4th wires 340d in inner coil layer 234 with different patterns / fills. That is, the first portion of the wire 340 forming the inner coil layer 234 is shown with a different pattern / fill. Figure 3G shows (i) the individual first wires 340a-340d in the inner coil layer 234 having different patterns / fills, and (ii) the individual first wires 340a-340d in the outer coil layer 236 having different patterns / fills. That is, the first and second portions of the wire 340 forming the coil layers 234, 236, respectively, are shown with different patterns / fills.

[0036] 1-3G together, in some aspects of the present technology, the coil layers 234, 236 can be configured to provide the catheter 120 with selective properties along the entire length of the catheter 120 or in selected regions of the catheter 120. Such properties may include flexibility (e.g., the ability of the catheter 120 to bend / bend laterally away from the longitudinal axis L), pushability (e.g., column strength, e.g., the ability of the catheter 120 to transmit longitudinal forces along the length of the catheter 120 from the proximal region 122 to the distal region 126 and distal tip region 128), torqueability (e.g., torque response, e.g., the ability of the catheter 120 to transmit rotational forces along the length of the catheter from the proximal region 122 to the distal region 126 and distal tip region 128), kink resistance (e.g., the ability of the catheter 120 to maintain its cross-sectional profile, such as inner diameter D, during compressive deformation), hoop strength (e.g., the ability of the catheter 120 to maintain its cross-sectional profile when a pressure differential exists between the lumen 121 of the catheter 120 and the environment surrounding the catheter 120, such as during aspiration of the lumen 121), and / or other properties known in the catheter art. For example, the number of wires 340 forming the coil layers 234, 236 and / or the pitch P between the wires 340 within the coil layers 234, 236 1~2 can be selected to provide the desired flexibility, pushability, torqueability, kink resistance, hoop strength, and the like.

[0037] More specifically, for example, the pitch P between the wires 340 1~2 Increasing the pitch P between the wires 340 may generally decrease the flexibility of the catheter 120 as the wires 340 extend more longitudinally (e.g., less circularly) about the longitudinal axis L of the catheter 120, while also increasing the pushability of the catheter 120. Conversely, increasing the pitch P between the wires 340 may also increase the pushability of the catheter 120. 1~2Reducing the number of wires 340 may generally increase the flexibility of the catheter 120 because the wires 340 extend in a more circular fashion around the longitudinal axis L of the catheter 120, but may also decrease the pushability of the catheter 120. Furthermore, increasing the number of wires 340 may decrease the flexibility of the catheter 120 but increase the pushability, torqueability, kink strength, and hoop strength. Conversely, decreasing the number of wires 340 may increase the flexibility of the catheter 120 but decrease the pushability, torqueability, kink strength, and hoop strength.

[0038] 4 and 5 are, for example, enlarged isometric views of a portion of catheter 120 shown in FIG. 1, in accordance with further embodiments of the present technology. Outer sheath 230 (FIG. 2) has been removed in FIGS. 4 and 5 for clarity. Referring first to FIG. 4, in the illustrated embodiment, pitch P between wires 340 is 1~2 is smaller (e.g., denser) than that shown in Figures 3A-3G. As explained in detail above, the smaller pitch P 1~2 5, in the illustrated embodiment, the pitch P between the wires 340 in the coil layers 234, 236 is 1~2 is different along different regions of the catheter 120, such as the distal region 526 and the proximal region 522. 1~2 5 and coil layers 234, 236 are not labeled in FIG. 5 for clarity, but are shown in FIGS. 2-4. For example, pitch P 1~2 is smaller in the distal region 526 than in the proximal region 522. Thus, as explained in detail above, the catheter 120 may be relatively more flexible in the distal region 526 than in the proximal region 522, but the proximal region 522 may provide good pushability for the catheter 120. More generally, referring together to FIGS. 1-5, the pitch P between the wires 340 1~2may vary one or more times along the length of catheter 120 (e.g., in regions 122, 124, 126, 128) and / or the pitch P 1~2 can vary along the same region of the catheter 120 such that the coil layers 234, 236 impart different flexibility and / or other properties along the same region of the catheter 120.

[0039] More generally, in some aspects of the present technology, the arrangement of the coil layers 234, 236 can enable the catheter 120 to be steered and positioned in hard-to-reach (e.g., tortuous) regions of a patient's anatomy (e.g., venous anatomy) while still having a relatively large size (e.g., 20 French, 24 French, greater than 24 French). More specifically, the coil layers 234, 236 can provide the catheter 120 with torqueability and pushability similar to conventional catheters including braided structures (e.g., braided mesh) or other reinforcing structures. Similarly, the coil layers 234, 236 can provide hoop strength and flexibility similar to or greater than conventional catheters including solid-wire coil structures, while also reducing kinking around tight bend radii. Furthermore, the coil layers 234, 236 allow the catheter 120 to have these properties without including a braided or other reinforcing structure, which allows the catheter 120 to be manufactured with a relatively thin inner liner 232 and / or a thin outer sheath 230, resulting in a thin-walled catheter 120. This allows the inner diameter D of the catheter 120 to be larger than other catheters labeled with the same outer diameter (OD) French size.

[0040] In some embodiments, catheter 120 can include more coil layers in addition to coil layers 234, 236. For example, Figure 6 is a side cross-sectional view of catheter 120 along line CC of Figure 1 in accordance with an additional embodiment of the present technology. In the illustrated embodiment, inner coil layer 234 is a first inner coil layer 234, outer coil layer 236 is a first outer coil layer 236 (collectively "first coil layers 234, 236"), and catheter 120 further includes a second inner coil layer 634 and a second outer coil layer 636 (collectively "second coil layers 634, 636"). First inner coil layer 234 can be referred to as the first coil layer 234, first outer coil layer 236 can be referred to as the second coil layer, second inner coil layer 634 can be referred to as the third coil layer, second outer coil layer 636 can be referred to as the fourth coil layer, and so on.

[0041] The second coil layers 634, 636 can be generally similar to or identical to the first coil layers 234, 236. For example, the second coil layers 634, 636 can comprise a plurality of individual wires that (i) extend in a first direction around the first outer coil layer 236 in a helical or spiral pattern about the longitudinal axis L (FIG. 1) to form the second inner coil layer 634, and (ii) turn back to extend in a second direction around the second inner coil layer 634 in a helical or spiral pattern about the longitudinal axis L to form the second outer coil layer 636 over the second inner coil layer 634. Additionally, the wires forming the second coil layers 634, 636 can be self-terminating in the distal tip region 128 (FIG. 1) of the catheter 120, as described in detail above. The second coil layers 634, 636 may extend along the entire length of the catheter 120 through each of the regions 122, 124, 126, 128 (FIG. 1), or may extend only partially along the length of the catheter 120 (e.g., in the distal region 126 and the distal tip region 128). That is, for example, (i) the second coil layer 634, 636 can self-terminate at the same location as the first coil layer 234, 236 so that the catheter 120 includes four coil layers along its entire length (e.g., the first coil layer 234, 236 and the second coil layer 634, 636 thereon), or (ii) the second coil layer 634, 636 can self-terminate at a different location than the first coil layer 234, 236 so that a portion of the catheter 120 includes four coil layers (e.g., the first coil layer 234, 236 and the second coil layer 634, 636 thereon) and a portion of the catheter 120 includes two coil layers (e.g., the first coil layer 234, 236). In some embodiments, the wire used to form the first coil layer 234, 236 and the second coil layer 634, 636 can be thinner to maintain the same or similar inner diameter D of the lumen 121 of the catheter 120.

[0042] In some embodiments, separate wires are used to form the first coil layer 234, 236 and the second coil layer 634, 636. In other embodiments, the same wire can be wrapped multiple times along the length of the catheter 120 to form the first coil layer 234, 236 and the second coil layer 634, 636. That is, for example, the same wire can be (i) wrapped distally along the inner liner 232 to form the first inner coil layer 234, (ii) wrapped proximally along the first inner coil layer 234 to form the first outer coil layer 236, (iii) wrapped distally along the first outer coil layer 236 to form the second inner coil layer 634, and then (iv) wrapped proximally along the second inner coil layer 634 to form the second outer coil layer 636. In such embodiments, the wires may be self-terminating at the distal junction between the first coil layers 234, 236, the proximal junction between the first outer coil layer 236 and the second inner coil layer 634, and the distal junction between the second coil layers 634, 636. Additionally, the number of wires and / or the pitch between the wires in the first coil layers 234, 236 and the second coil layers 634, 636 may vary, as described in detail above.

[0043] In some aspects of the present technology, the second coil layers 634, 636 can increase the pushability, torqueability, hoop strength, and / or other aspects of the catheter 120. For example, referring to FIGS. 3A-3G and 6 together, applying a torque to the catheter 120 in a first direction (e.g., a clockwise direction) can compress / close the first inner coil layer 234 (e.g., act to decrease the first pitch P1). Conversely, applying a torque to the catheter 120 in the first direction can simultaneously expand / open the first outer coil layer 236 (e.g., act to increase the second pitch P2). Similarly, applying a torque to the catheter 120 in a second direction opposite the first direction (e.g., a counterclockwise direction) can simultaneously expand / open the first inner coil layer 234 and compress / close the first outer coil layer 236. These opposing forces can generate an asymmetric torque on the catheter 120. The second coil layers 634, 636 can have a similar torque response and, in some aspects of the present technology, can help make the torque response of the catheter 120 more symmetrical by balancing the opposing torque response of the first coil layers 234, 236.

[0044] 7 is a side cross-sectional view of a catheter 120 taken along line CC of FIG. 1 in accordance with an additional embodiment of the present technology. In the illustrated embodiment, the catheter 120 further includes a third inner coil layer 734 and a third outer coil layer 736 (collectively "third coil layers 734, 736"). The third coil layers 734, 736 may be generally similar to or identical to the first coil layers 234, 236 and the second coil layers 634, 636. For example, the third coil layer 734, 736 may comprise a plurality of individual wires that (i) extend in a first direction around the second outer coil layer 636 in a helical or spiral pattern about the longitudinal axis L (FIG. 1) to form the third inner coil layer 734, and (ii) fold back to extend in a second direction around the third inner coil layer 734 in a helical or spiral pattern about the longitudinal axis L to form the third outer coil layer 736 on the third inner coil layer 734. Additionally, the wires forming the third coil layers 734, 736 may be self-terminating in the distal tip region 128 (FIG. 1) of the catheter 120, as described in detail above. The third coil layer 734, 736 can extend along the entire length of the catheter 120 through each of the regions 122, 124, 126, 128 (FIG. 1), or can extend only partially along the length of the catheter 120 (e.g., in the distal region 126 and distal tip region 128). In some embodiments, the wire used to form the first coil layer 234, 236, the second coil layer 634, 636, and the third coil layer 734, 736 can be thinner to maintain the same or similar inner diameter D of the lumen 121 of the catheter 120. In other embodiments, the catheter 120 can include more than three coil layers (e.g., four or more than four coil layers), which can be formed from the same or separate wires.

[0045] In some embodiments, separate wires are used to form the first coil layer 234, 236, the second coil layer 634, 636, and the third coil layer 734, 736. In other embodiments, the same wire can be used to form some or all of the coil layers. For example, the same wire can be wrapped multiple times along the length of the catheter 120 to form the first coil layer 234, 236, the second coil layer 634, 636, and / or the third coil layer 734, 736. That is, for example, the same wire can be (i) wound distally along the inner liner 232 to form the first inner coil layer 234, (ii) wound proximally along the inner coil layer 234 to form the first outer coil layer 236, (iii) wound distally along the first outer coil layer 236 to form the second inner coil layer 634, (iv) wound proximally along the second inner coil layer 634 to form the second outer coil layer 636, (v) wound distally along the second outer coil layer 636 to form the third inner coil layer 734, and then (vi) wound proximally along the third inner coil layer 734 to form the third outer coil layer 736. In such an embodiment, the wire may be self-terminating at the distal junction between the first coil layers 234, 236, the proximal junction between the first outer coil layer 236 and the second inner coil layer 634, and the distal junction between the second coil layers 634, 636, the proximal junction between the second outer coil layer 636 and the third inner coil layer 734, and the distal junction between the third coil layers 734, 736. Alternatively, for example, the same wire may be used to form the first coil layers 234, 236 and the second coil layers 634, 636, and a separate wire may be used to form the third coil layers 734, 736, or the same wire may be used to form the second coil layers 634, 636 and the third coil layers 734, 736, and a separate wire may be used to form the first coil layers 234, 236. Additionally, the number of wires and / or the pitch between the wires in the first coil layers 234, 236, second coil layers 634, 636, and third coil layers 734, 736 may vary as described in detail above.

[0046] In some aspects of the present technology, the third coil layer 734, 736 can further increase the pushability, torqueability, hoop strength, and / or other properties of the catheter 120. For example, the third coil layer 734, 736 can help make the torque response of the catheter 120 more symmetrical by balancing the opposing torque responses of the first coil layer 234, 236 and / or the second coil layer 634, 636.

[0047] In some embodiments, catheter 120 can include one or more lumens, puller wires, and / or other components. For example, FIG. 8 is a side cross-sectional view of catheter 120 taken along line CC of FIG. 1 in accordance with an additional embodiment of the present technology. In the illustrated embodiment, catheter 120 includes a first component 850 positioned between coil layers 234, 236, a second component 851 positioned between inner liner 232 and inner coil layer 234, and a third component 852 positioned between outer sheath 230 and outer coil layer 236. Catheter 120 can include any number of components 850-852 positioned at different circumferential positions around lumen 121.

[0048] One or more of the first through third components 850, 851, 852 (“components 850, 851, 852”) may be lumens into which other devices may be inserted and / or into which fluid may be injected or withdrawn (e.g., to inflate a balloon coupled to catheter 120). In some aspects of the present technology in which one or more of components 850, 851, 852 comprise an inflation lumen, coil layers 234, 236 can provide support for the inflation lumen while also enabling improved (e.g., minimized) inflation / deflation times, even when catheter 120 is positioned within highly tortuous anatomy. In some embodiments, one or more of components 850, 851, 852 comprise a lumen through which contrast fluid may be injected to facilitate visualization of a distal portion of catheter 120 (e.g., distal region 126 and / or distal tip region 128 shown in FIG. 1 ). In such embodiments, components 850, 851, 852 may comprise tubes, extrusions, elongated members, etc. The lumens may have a circular cross-sectional shape as illustrated in FIG. 8, or may have other cross-sectional shapes. For example, first through third lumens 853a through 853c (e.g., contrast injection lumens) are each shown in FIG. 8 as having a U-shaped cross-sectional shape. More specifically, lumens 853a through 853c may extend partially or completely circumferentially about longitudinal axis L of catheter 120. In the illustrated embodiment, first lumen 853a extends between outer sheath 850 and outer coil layer 856, second lumen 853b extends between coil layers 854, 856, and third lumen 853c extends between inner coil layer 854 and inner liner 852.

[0049] In some embodiments, one or more of components 850, 851, 852 can comprise, for example, a puller wire configured to deflect a portion of catheter 120 (e.g., distal region 126 and / or distal tip region 128 shown in FIG. 1 ). For example, the puller wire can be secured to one or both of coil layers 234, 236 at the distal end and can be pulled back proximally to deflect catheter 120. In some embodiments, if catheter 120 includes more than the two illustrated coil layers 234, 236 (e.g., as described in detail above with reference to FIGS. 6 and 7 ), one or more of components 850, 851, 852 can be positioned between different (e.g., adjacent) ones of the coil layers. For example, multiple inflation lumens and / or fluid infusion lumens can be positioned between different coil layers to facilitate inflation of multiple balloons.

[0050] In some aspects of the present technology, the first component 850 can be secured in place between the coil layers 234, 234 during manufacturing by (i) wrapping the wire 340 (FIGS. 3A-3G) around the inner liner 232 before positioning the first component over the inner coil layer 234, and then (ii) further wrapping the wire 340 over the first component 850 and the inner coil layer 236 to form the outer coil layer 236. In some aspects of the present technology, as described in more detail below with reference to FIG. 9, the catheter 120 can be manufactured to include the components 850, 851, 852 using a single machine setup due to the self-terminating ends of the coil layers 234, 236. In additional aspects of the present technology, the components 850, 851, 852 can be formed in the catheter 120 without increasing, or substantially increasing, the thickness T of the catheter 120 compared to conventional manufacturing methods. III. SELECTED EMBODIMENTS OF A METHOD FOR MANUFACTURING A CATHETER HAVING A SELF-TERMINATING COIL

[0051] 9 is a flow diagram of a process or method 960 for manufacturing a catheter (e.g., catheter 120) in accordance with an embodiment of the present technology. Although certain features of method 960 are described in the context of catheter 120 shown in FIGS. 1-8 for purposes of illustration, one skilled in the art will readily understand that method 960 can be performed to form other catheters described herein.

[0052] At block 961, the method 960 may include positioning the inner liner 232 along a mandrel, hypotube, or another elongated member. In some embodiments, the inner liner 232 is stretched along the mandrel to have a desired thickness.

[0053] At block 962, the method 960 may include coiling / winding the wire 340 around the mandrel in a first direction (e.g., distal direction D) and onto the inner liner 232 to form the inner coil layer 234. As described in detail above, the number of wires 340 and / or the pitch P1 between the wires 340 may be varied to provide desired characteristics of the catheter 120. In some embodiments, tension is applied to the wire 340 as it is coiled onto the inner liner 232 so that the wire 340 is tightly wrapped around the inner liner 232. The wire 340 may be coiled manually by a user or by machine.

[0054] At block 963, the method 960 may include coiling / winding the wire 340 around the mandrel and over the inner coil layer 234 in a second direction opposite the first direction (e.g., proximal direction P) to form the outer coil layer 236. That is, the coiling direction may be reversed to form the distal end 342 of the wire 340, for example, in the distal tip region 128 of the catheter 120. As described in detail above, the pitch P2 between the wires 340 may be varied to provide desired characteristics of the catheter 120. In some embodiments, tension is applied to the wire 340 as it is coiled over the inner coil layer 234 so that the wire 340 is tightly wrapped around the inner coil layer 234.

[0055] At block 964, the method 960 may optionally include forming one or more additional inner and outer coil layers over the coil layers 234, 236, such as the second coil layers 634, 636, the third coil layers 734, 736, and / or additional coil layers. As described in detail above, the additional inner and outer coil layers may be formed in the same manner as the coil layers 234, 236 (blocks 962 and 963), and may be formed using separate wires and / or the same wires 340 used to form the coil layers 234, 236.

[0056] At block 965, the method 960 may include positioning the outer sheath 230 over the inner liner 232 and the coil layers 234, 236 (and any additional coil layers). In some embodiments, the outer sheath 230 is stretched over a mandrel to have a desired thickness.

[0057] At block 966, the method 960 may include bonding the outer sheath 230, the coil layers 234, 236 (and any additional coil layers), and the inner liner 232 together to form the catheter 120. For example, the outer sheath 230 and the inner liner 232, along with the coil layers 234, 236 therebetween, may be heat shrunk, fused, laminated, or otherwise secured together.

[0058] Finally, in block 967, method 960 may include removing catheter 120 from the mandrel. In some embodiments, method 960 may optionally include positioning one or more components (e.g., components 850-852), such as a lumen or pull wire, during any of the steps described in blocks 961-965 so that the component is integrally formed in the wall of catheter 120. IV. SELECTED EMBODIMENTS OF THE CLOMATIC TREATMENT METHOD

[0059] 10A and 10B are side views of a distal region 126 of a catheter 120 of a clot treatment system 100 during a procedure for removing clot material CM (e.g., a pulmonary embolism) from within a blood vessel BV (e.g., a pulmonary vessel) of a patient (e.g., a human patient) in accordance with an embodiment of the present technology. As noted above, in some embodiments, the clot removal procedure illustrated in FIGS. 10A and 10B may be generally similar to or identical to any of the clot removal procedures disclosed in U.S. patent application Ser. No. 16 / 536,185, filed Aug. 8, 2019, entitled "SYSTEM FOR TREATING EMBOLISM AND ASSOCIATED DEVICES AND METHODS," which is incorporated herein by reference in its entirety.

[0060] 1 and 10A , the catheter 120 may be advanced through the patient and proximate the blood vessel BV to the clot material CM (e.g., advanced to a treatment site within the blood vessel BV). In some embodiments, the catheter 120 is advanced through the blood vessel BV until a distal end 125 of the catheter 120 is positioned proximate a proximal portion of the clot material CM. The location of the distal end 125 may be confirmed or located via visualization of the marker band 129 using fluoroscopy or another imaging procedure (e.g., a radiological procedure). In other embodiments, the distal end 125 may be positioned at least partially within or distal to the clot material CM.

[0061] In some aspects of the present technology, the catheter 120 is configured to bend / bend within a tortuous (e.g., difficult-to-reach) region of the blood vessel BV. For example, in the illustrated embodiment, the catheter 120 bends around a bend 1070 within the blood vessel BV, which may have a relatively small radius of curvature. The portion of the blood vessel BV distal to the bend 1070 may be difficult to reach due to the required approach angle, various anatomical structures of the blood vessel BV, and / or irregularities due to patient disease. In some embodiments, the blood vessel BV may be the left pulmonary artery, the temporal artery, the inferior vena cava, or a portion of the right atrium. In some embodiments, the clot material CM may be a clot in transit (CIT) within the right atrium.

[0062] Access to the pulmonary vessels may be achieved through the patient's vascular system, for example, via the femoral vein. In some embodiments, the clot treatment system 100 may include an introducer (e.g., a Y-connector with a hemostatic valve, not shown), which may be partially inserted into the femoral vein. A guidewire (not shown) may be guided through the introducer into the femoral vein and navigated through the right atrium, tricuspid valve, right ventricle, pulmonary valve, and into the main pulmonary artery. Depending on the location of the clot material CM, the guidewire may be guided into one or more branches of the right and / or left pulmonary arteries. In some embodiments, the guidewire may extend entirely or partially through the clot material CM. In other embodiments, the guidewire may extend to a position just proximal to the clot material CM. After positioning the guidewire, a catheter 120 may be placed over the guidewire and advanced to a position adjacent to the clot material CM, as shown in FIG. 10A . In some embodiments, the guidewire may then be withdrawn, while in other embodiments, the guidewire may remain and be used to guide other catheters (e.g., delivery catheters, additional aspiration guide catheters), interventional devices, etc., to the treatment site. However, it will be understood that other access locations to the patient's venous circulation are possible and consistent with the present technology. For example, the user may gain access through the jugular vein, subclavian vein, brachial vein, or any other vein that connects to or ultimately leads to the superior vena cava. Using other blood vessels closer to the right atrium of the patient's heart may also be advantageous, as it reduces the length of equipment needed to reach the clot material CM.

[0063] 1 and 10B , the pressure source 106 is configured to generate (e.g., form, create, fill, or accumulate) a vacuum (e.g., a negative relative pressure) and accumulate the vacuum for subsequent application to the catheter 120. For example, after positioning the catheter 120 in proximity to the clot material CM, a user can first close the fluid control device 114 before generating a vacuum in the pressure source 106, for example, by pulling back on the plunger of a syringe coupled to the connector 116. In this manner, a vacuum is built (e.g., a negative pressure is maintained) in the pressure source 106 before the pressure source 106 is fluidly connected to the lumen 121 of the catheter 120. To suction the lumen 121 of the catheter 120, a user can open the fluid control device 114 to fluidly connect the pressure source 106 to the catheter 120, thereby applying or releasing the vacuum accumulated in the pressure source 106 to the lumen 121 of the catheter 120.

[0064] The opening of the fluid control device 114 instantaneously or near-instantaneously applies the built-up vacuum pressure to the tubing assembly 110 and the catheter 120, thereby generating a suction pulse throughout the catheter 120. In particular, suction is applied to the distal tip region 128 of the catheter 120 to draw / aspirate at least a portion of the clot material CM into the lumen 121 of the catheter 120, as shown in FIG. 10B . In one aspect of the present technology, pre-charging or building up vacuum in the pressure source 106 prior to applying vacuum to the lumen 121 of the catheter 120 is expected to generate a greater suction force and corresponding fluid flow rate at and / or near the distal tip region 128 of the catheter 120 compared to simply activating the pressure source 106 while fluidly connected to the catheter 120. In other embodiments, the pressure source 106 can be activated while the fluid control device 114 is open to aspirate the clot material CM.

[0065] At times, as shown in FIG. 10B , releasing the vacuum built up in the pressure source to suction the lumen 121 of the catheter 120 may remove substantially all (e.g., a desired amount) of the clot material CM from the blood vessel BV. That is, a single suction pulse may adequately remove the clot material CM from the blood vessel BV. In other embodiments, a portion of the clot material CM may remain within the blood vessel BV. In such cases, the user may desire to reapply vacuum pressure (performing an “suction pass”) to remove all or a portion of the remaining clot material CM within the blood vessel BV. In such cases, the pressure source 106 may be disconnected from the tubing assembly 110 and vented (e.g., removing the aspirated clot removal) before the pressure source 106 is reconnected to the tubing assembly 110 and activated again. After the desired amount of clot material CM has been removed, the catheter 120 may be withdrawn from the patient.

[0066] In some aspects of the present technology, the relatively greater flexibility and torqueability of catheter 120 (e.g., as provided by coil layers 234, 236 shown in FIGS. 3A-3G ) allows catheter 120 to be positioned in hard-to-reach areas of blood vessel BV (or elsewhere in the patient's vasculature) without reducing the size of lumen 121. It is anticipated that increasing the size of lumen 121 will provide greater suction force (e.g., greater vacuum impulse) for a shorter period of time. In some embodiments, greater suction force can facilitate removal of clot material from a patient's blood vessel, even when the material is strongly lodged or adherent within the vessel (e.g., chronic clots). Thus, in contrast to conventional catheters, catheter 120 can be used to generate greater suction force for improved clot removal in hard-to-reach areas of the vasculature. In an additional aspect of the present technology, the coil layers 234, 236 (FIGS. 3A-3G) can provide high hoop strength along the distal region 126 of the catheter 120, which inhibits or prevents kinking or other undesired movement of the catheter 120 when the pressure source 106 is used to generate a suction pulse at the distal region 126 of the catheter 120. V. Additional Examples

[0067] Several aspects of the present technology are described in the following examples. 1. A catheter comprising: a longitudinal axis; a plurality of wires, the wires being coiled about the longitudinal axis in a first direction and spaced apart to form a first coil layer, and the wires being coiled about the longitudinal axis in a second direction opposite the first direction and spaced apart on top of the first coil layer to form a second coil layer on top of the first coil layer; an outer sheath over the plurality of wires; A catheter comprising: 2. The catheter of example 1, further comprising an inner liner, wherein the wire is coiled over the inner liner. 3. The catheter of example 1 or 2, wherein the wires in the first coil layer have a helical arrangement with a first orientation and the wires in the second coil layer have a helical arrangement with a second orientation opposite the first orientation. 4. A catheter described in any one of Examples 1 to 3, wherein the wires each include a continuous end where the wire switches from a first direction to a second direction and transitions from a first coil layer to a second coil layer. 5. A catheter described in any one of Examples 1 to 4, wherein the wires each include a self-terminating end where the wire switches from a first direction to a second direction and transitions from a first coil layer to a second coil layer. 6. A catheter described in any one of Examples 1 to 5, wherein the wire has a first pitch in the first coil layer and a second pitch in the second coil layer, the first pitch and the second pitch being the same. 7. The catheter of any one of Examples 1 to 6, wherein the wire has a first pitch in the first coil layer and a second pitch in the second coil layer, the first pitch and the second pitch being different. 8. A catheter described in any one of Examples 1 to 7, wherein the wire has a first pitch in the first coil layer and a second pitch in the second coil layer, and the first pitch and / or the second pitch vary along the longitudinal axis. 9. A catheter described in any one of Examples 1 to 8, wherein the wire is further (a) coiled around the longitudinal axis in a first direction to form a third coil layer on top of the second coil layer, and (b) coiled around the longitudinal axis in a second direction on top of the third coil layer to form a fourth coil layer on top of the third coil layer. 10. A catheter as described in Example 9, wherein the wires each include: (a) a first self-terminating end where the wire switches from a first direction to a second direction and transitions from the first coil layer to the second coil layer; and (b) a second self-terminating end where the wire switches from the second direction to the first direction and transitions from the second coil layer to the third coil layer. 11. The catheter of example 10, wherein the first self-terminating end is located at a distal end of the catheter and the second self-terminating end is located at a proximal end of the catheter. 12. The catheter of example 10 or 11, wherein the first self-terminating end is at a different position along the longitudinal axis relative to the second self-terminating end. 13. The catheter of any of examples 9-12, wherein the third coil layer extends only partially over the second coil layer along the longitudinal axis. 14. A catheter of any of Examples 9 to 12, wherein the third coil layer extends entirely over the second coil layer along the longitudinal axis. 15. A catheter described in any one of Examples 1 to 8, wherein the wire is a first wire and further comprises a plurality of second wires, the second wires being (a) coiled around the longitudinal axis in a first direction to form a third coil layer on the second coil layer, and (b) coiled around the longitudinal axis in a second direction on top of the third coil layer to form a fourth coil layer on top of the third coil layer. 16. A catheter as described in Example 15, wherein each of the first wires includes a first self-terminating end where the first wire switches from the first direction to the second direction and transitions from the first coil layer to the second coil layer, and each of the second wires includes a second self-terminating end where the second wire switches from the first direction to the second direction and transitions from the third coil layer to the fourth coil layer. 17. The catheter of example 16, wherein the first self-terminating end is positioned at the same position along the longitudinal axis as the second self-terminating end. 18. The catheter of example 17, wherein the first self-terminating end and the second self-terminating end are located at a distal end of the catheter. 19. The catheter of example 16, wherein the first self-terminating end is positioned at a different position along the longitudinal axis relative to the second self-terminating end. 20. A catheter of any of examples 15 to 19, wherein the third coil layer extends only partially over the second coil layer along the longitudinal axis. 21. A catheter of any of examples 15 to 19, wherein the third coil layer extends entirely over the second coil layer along the longitudinal axis. 22. The catheter of any one of examples 1 to 21, wherein the wire has a rectangular cross-sectional shape. 23. The catheter of any one of examples 1 to 22, wherein the plurality of wires comprises four wires. 24. The catheter of any one of examples 1 to 22, wherein the plurality of wires comprises 12 wires. 25. The catheter of any one of Examples 1 to 24, further comprising an inner liner defining a lumen, the wire being coiled over the inner liner, and the lumen having a diameter of 20 French or greater. 26. The catheter of any one of Examples 1 to 25, further comprising a lumen extending between the inner coil layer and the outer coil layer. 27. The catheter of any one of Examples 1 to 26, further comprising a lumen extending between the outer coil layer and the outer sheath. 28. an inner liner, the wire being coiled on the inner liner; 28. The catheter of any one of Examples 1 to 27, further comprising a lumen extending between the inner coil layer and the inner liner. 29. A method of manufacturing a catheter, the method comprising: Coiling a plurality of wires in a first direction around a mandrel to form an inner coil layer; coiling the wire around the mandrel in a second direction opposite the first direction to form an outer coil layer over the inner coil layer; Positioning an outer sheath over the inner coil layer and the outer coil layer; bonding an outer sheath to the inner coil layer and the outer coil layer; A method comprising: 30. The method of embodiment 29, wherein the method further includes positioning an inner liner over the mandrel, and wherein coiling the wire in a first direction around the mandrel includes coiling the wire in the first direction over the inner liner to form an inner coil layer over the inner liner. 31. The method of example 30, wherein bonding the outer sheath to the inner coil layer and the outer coil layer comprises fusing the outer sheath and inner liner together. 32. The method of any one of Examples 29 to 31, wherein the wire in the first coil layer has a helical arrangement with a first orientation, and the wire in the second coil layer has a helical arrangement with a second orientation opposite the first orientation. 33. The method of any one of Examples 29 to 32, wherein coiling the wire around the mandrel in a first direction to form the inner coil layer includes varying the pitch between the wires in the first direction. 34. The method of any one of Examples 29 to 33, wherein coiling the wire around the mandrel in the second direction to form the outer coil layer includes varying the pitch between the wires in the second direction. 35. The method of any one of Examples 29 to 34, wherein the method further includes positioning an elongated component over the inner coil layer, and wherein coiling the wire in a second direction around the mandrel to form the outer coil layer includes coiling the wire over the elongated component to secure the elongated component between the inner coil layer and the outer coil layer. 36. The method of example 35, wherein the elongate component comprises a lumen. 37. The method of any one of Examples 29 to 36, wherein coiling the wire in a second direction around the mandrel includes forming continuous ends of each of the wires where the wire switches from the first direction to the second direction and transitions from an inner coil layer to an outer coil layer. 38. The method of any one of Examples 29 to 37, wherein coiling the wire around the mandrel in a second direction includes forming a self-terminating end of each of the wires where the wires switch from the first direction. 39. A catheter, a longitudinal axis; A plurality of wires, the wire is coiled in a first direction about the longitudinal axis to form a first coil layer; the wire is coiled about the longitudinal axis in a second direction opposite the first direction over the first coil layer to form a second coil layer over the first coil layer; a plurality of wires, each wire including a continuous end where the wire switches from a first direction to a second direction and transitions from an inner coil layer to an outer coil layer; an outer sheath over the plurality of wires; A catheter comprising: 40. A catheter, a longitudinal axis; A plurality of wires, the wire is coiled in a first direction about the longitudinal axis to form a first coil layer; the wire is coiled about the longitudinal axis in a second direction opposite the first direction over the first coil layer to form a second coil layer over the first coil layer; a plurality of wires, each including a self-terminating end where the wire switches from a first direction to a second direction and transitions from a first coil layer to a second coil layer; an outer sheath over the wire; A catheter comprising: VI. Conclusion

[0068] The above detailed description of embodiments of the present technology is not intended to be exhaustive or to limit the present technology to the precise form disclosed above. While specific embodiments and examples of the present technology have been 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. The various embodiments described herein may also be combined to provide further embodiments.

[0069] From the foregoing, it will be understood that, although specific embodiments of the present technology have been 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.

[0070] Furthermore, unless the word "or" is expressly limited in reference to a list of two or more items to mean only a single item exclusively from the other 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, but not the exclusion of any more of the same features and / or other features of additional types. While specific embodiments have been described herein for illustrative purposes, it will also be understood that various modifications can be made without departing from the present technology. Furthermore, while advantages associated with some embodiments of the present 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 present technology. Thus, the present disclosure and related technology may encompass other embodiments not explicitly shown or described herein.

Claims

1. A catheter, a longitudinal axis; a plurality of wires, the wires being coiled around the longitudinal axis in a first direction spaced apart to form a first coil layer, and the wires being coiled around the longitudinal axis in a second direction opposite the first direction and spaced apart on top of the first coil layer to form a second coil layer on top of the first coil layer; an outer sheath over the plurality of wires; A catheter comprising:

2. The catheter of claim 1 , further comprising an inner liner, the wire being coiled over the inner liner.

3. 10. The catheter of claim 1, wherein the wires in the first coil layer have a helical arrangement with a first orientation and the wires in the second coil layer have a helical arrangement with a second orientation opposite the first orientation.

4. The catheter of claim 1 , wherein the wires each include a continuous end where the wire switches from the first direction to the second direction and transitions from the first coil layer to the second coil layer.

5. 10. The catheter of claim 1, wherein the wires each include a self-terminating end where the wire switches from the first direction to the second direction and transitions from the first coil layer to the second coil layer.

6. 10. The catheter of claim 1, wherein the wire has a first pitch in the first coil layer and a second pitch in the second coil layer, the first pitch and the second pitch being the same.

7. 10. The catheter of claim 1, wherein the wire has a first pitch in the first coil layer and a second pitch in the second coil layer, the first pitch and the second pitch being different.

8. 2. The catheter of claim 1, wherein the wire has a first pitch in the first coil layer and a second pitch in the second coil layer, and the first pitch and / or the second pitch vary along the longitudinal axis.

9. 2. The catheter of claim 1, wherein the wire is further (a) coiled about the longitudinal axis in the first direction to form a third coil layer above the second coil layer, and (b) coiled about the longitudinal axis in the second direction above the third coil layer to form a fourth coil layer above the third coil layer.

10. 10. The catheter of claim 9, wherein the wires each include: (a) a first self-terminating end where the wire switches from the first direction to the second direction and transitions from the first coil layer to the second coil layer; and (b) a second self-terminating end where the wire switches from the second direction to the first direction and transitions from the second coil layer to the third coil layer.

11. The catheter of claim 10, wherein the first self-terminating end is located at a distal end of the catheter and the second self-terminating end is located at a proximal end of the catheter.

12. The catheter of claim 10 , wherein the first self-terminating end is at a different location along the longitudinal axis relative to the second self-terminating end.

13. 10. The catheter of claim 9, wherein the third coil layer extends only partially over the second coil layer along the longitudinal axis.

14. 10. The catheter of claim 9, wherein the third coil layer extends entirely over the second coil layer along the longitudinal axis.

15. 2. The catheter of claim 1, wherein the wire is a first wire and further comprising a plurality of second wires, the second wires (a) being coiled around the longitudinal axis in the first direction to form a third coil layer on top of the second coil layer, and (b) being coiled around the longitudinal axis in the second direction on top of the third coil layer to form a fourth coil layer on top of the third coil layer.

16. 16. The catheter of claim 15, wherein each of the first wires includes a first self-terminating end where the first wire switches from the first direction to the second direction and transitions from the first coil layer to the second coil layer, and each of the second wires includes a second self-terminating end where the second wire switches from the first direction to the second direction and transitions from the third coil layer to the fourth coil layer.

17. 17. The catheter of claim 16, wherein the first self-terminating end is positioned at the same location along the longitudinal axis relative to the second self-terminating end.

18. 17. The catheter of claim 16, wherein the first self-terminating end and the second self-terminating end are located at a distal end of the catheter.

19. 17. The catheter of claim 16, wherein the first self-terminating end is positioned at a different position along the longitudinal axis relative to the second self-terminating end.

20. 16. The catheter of claim 15, wherein the third coil layer extends only partially over the second coil layer along the longitudinal axis.

21. 16. The catheter of claim 15, wherein the third coil layer extends entirely over the second coil layer along the longitudinal axis.

22. The catheter of claim 1 , wherein the wire has a rectangular cross-sectional shape.

23. The catheter of claim 1 , wherein the plurality of wires comprises four wires.

24. The catheter of claim 1 , wherein the plurality of wires comprises 12 wires.

25. 10. The catheter of claim 1, further comprising an inner liner defining a lumen, the wire being coiled over the inner liner, the lumen having a diameter of 20 French or greater.

26. The catheter of claim 1 , further comprising a lumen extending between the inner coil layer and the outer coil layer.

27. The catheter of claim 1 , further comprising a lumen extending between the outer coil layer and the outer sheath.

28. an inner liner, the wire being coiled on the inner liner; a lumen extending between the inner coil layer and the inner liner; The catheter of claim 1 further comprising:

29. 1. A method of manufacturing a catheter, the method comprising: Coiling a plurality of wires in a first direction around a mandrel to form an inner coil layer; coiling the wire around the mandrel in a second direction opposite the first direction to form an outer coil layer over the inner coil layer; positioning an outer sheath over the inner coil layer and the outer coil layer; bonding the outer sheath to the inner coil layer and the outer coil layer; A method comprising:

30. 30. The method of claim 29, further comprising positioning an inner liner over the mandrel, and wherein coiling the wire in the first direction around the mandrel comprises coiling the wire in the first direction over the inner liner to form the inner coil layer over the inner liner.

31. 31. The method of claim 30, wherein bonding the outer sheath to the inner coil layer and the outer coil layer comprises fusing the outer sheath and inner liner together.

32. 30. The method of claim 29, wherein the wires in the first coil layer have a helical arrangement with a first orientation and the wires in the second coil layer have a helical arrangement with a second orientation opposite the first orientation.

33. 30. The method of claim 29, wherein coiling the wire around the mandrel in the first direction to form the inner coil layer includes varying a pitch between the wires in the first direction.

34. 30. The method of claim 29, wherein coiling the wire around the mandrel in the second direction to form the outer coil layer includes varying a pitch between the wires in the second direction.

35. 30. The method of claim 29, wherein the method further includes positioning an elongated component over the inner coil layer, and wherein coiling the wire in the second direction around the mandrel to form the outer coil layer includes coiling the wire over the elongated component to secure the elongated component between the inner coil layer and the outer coil layer.

36. The method of claim 35 , wherein the elongate component comprises a lumen.

37. 30. The method of claim 29, wherein coiling the wire in the second direction around the mandrel includes forming a continuous end of each of the wires where the wire switches from the first direction to the second direction and transitions from the inner coil layer to the outer coil layer.

38. 30. The method of claim 29, wherein coiling the wire in the second direction around the mandrel includes forming a self-terminating end of each of the wires where the wire switches from the first direction to the second direction and transitions from the inner coil layer to the outer coil layer.

39. A catheter, a longitudinal axis; A plurality of wires, the wire is coiled in a first direction about the longitudinal axis to form a first coil layer; the wire is coiled about the longitudinal axis in a second direction opposite the first direction over the first coil layer to form a second coil layer over the first coil layer; a plurality of wires, each of the wires including a self-terminating end where the wire switches from the first direction to the second direction and transitions from the first coil layer to the second coil layer; an outer sheath over the wire; A catheter comprising:

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