WO2024125783A1

WO2024125783A1 - Catheters, systems, and manufacture thereof

Info

Publication number: WO2024125783A1
Application number: PCT/EP2022/085839
Authority: WO
Inventors: Johannes HASLER; Steffan DANIEL; Bruno BAHNMÜLLER; Bedjet Aziri; Fabian Haller
Original assignee: Straub Medical AG
Current assignee: Straub Medical AG
Priority date: 2022-12-14
Filing date: 2022-12-14
Publication date: 2024-06-20
Anticipated expiration: 2025-06-14
Also published as: EP4633708A1

Abstract

The disclosure is directed to a catheter having a longitudinal tube and a distal tip, wherein the tube has a cylindrical tube wall comprising tube material and defining a cylindrical lumen, wherein the tube comprises a proximal end and a distal end region in a longitudinal direction, wherein the tube comprises a reinforcement configured to reinforce the distal end of the tube.

Description

246 742 p9 Catheters, Systems, and Manufacture thereof Technical Field The present disclosure relates to a catheters, thrombectomy or atherectomy systems having a catheter, as well as a manufacturing methods for a catheter. Background During thrombectomy and/or atherectomy procedures, a catheter may be introduced into a vessel to aspirate, and/or macerate occlusive material. However, such devices may be complicated, including a catheter body, one or more rotating parts, a stator to support rotation. The manufacture of the various separate components may lead to wasted material, high production costs, and low sustainability. Embodiments of the present disclosure are directed to catheters providing more stream-lined manufacture, leading to reduced cost, waste, and higher sustainability. Summary The present disclosure aims at providing a catheter which allows for simplification as to the manufacture, and may be more sustainable. Also, the disclosure may be advantageous as regards the use of a catheter during a procedure, such as reduced undesired friction, increased torsion stiffness, and improvised guidance, flexibility, and navigation through tortuous anatomy. According to the disclosure, a catheter has a longitudinal tube and a distal tip. The tube has a cylindrical tube wall defining a cylindrical lumen. The tube comprises a proximal end and a distal end region having a most distal end along a longitudinal direction, wherein the tube extends between, optionally is continuous between, the proximal end and the distal end region. The distal end region of the tube comprises a reinforcement to reinforce the distal end of the tube. The reinforcement may be configured such that the tube at the distal end region is reinforced relative to (compared to) at least a part of the tube proximal to the distal end region of the tube, optionally relative to the proximal end of the tube. The reinforcement may only be provided at the distal end region of the tube, and the tube outside the distal end region may be free from (said or optionally another) reinforcement. The distal end region of the tube may be stiffer than at least a part of the tube proximal to the distal end region of the tube, e.g. than the tube outside the distal end. For example, the distal end region may be stiffer and/or stronger than the proximal end of the tube. In embodiments, the distal end region of the tube comprising the reinforcement may be configured to withstand at least 10 N (without deformation). (10 N may be regarded as the maximum force a user/physician may be able to push the catheter during a procedure in the distal direction towards the treatment area, when grasping the catheter at its proximal end with a hand.) Alternatively or additionally, the distal end region of the tube comprising the reinforcement may be configured such that it does not kink when used, in particular in a worse case anatomical model. The reinforcement may impart stiffness/strength to the tube such that the stiffness of the tube at the distal end region of the tube is higher than outside the distal end region of the tube (e.g. in the remaining tube, e.g. proximal to the distal end region of the tube), optionally higher than at the proximal end of the tube. E.g. the reinforcement strength may be indicative to the resistance to bending. The reinforcement may impart stiffness to the tube such that the flexibility of the tube at the distal end region of the tube is lower than outside the distal end region of the tube (e.g. in the remaining tube), optionally lower than at the proximal end of the tube. The distal end region of the tube may be stiffer than the remaining tube or at least stiffer than the region of the tube adjacent (proximal) to the distal end of the tube. The reinforcement may optionally be integral with the tube. The distal end region of the tube represents/includes the distal tip of the catheter, such that the distal tip of the catheter comprises the reinforcement, or the distal tip of the catheter includes a (rotatable) tip borne/held/supported by the distal end region of the tube (and rotatable relative to the tube), wherein the reinforcement supports bearing/holding of the (rotatable) tip. The tube may be continuous between the proximal end and the distal end region of the tube. Accordingly, the tube may be a single piece and without interruptions between the proximal end and distal end region as defined. The proximal end and the distal end of the tube may refer to the (outer)most distal end (e.g., where the distal end terminates) and (outer)most proximal end (e.g., where the proximal end terminates) of the tube, respectively. The tube has a distal end region, which corresponds to the end portion of the tube in the distal direction. The distal end region of the tube does not need to be the distal tip of the catheter, but includes the most distal end of the tube. Alternatively, the distal end region of the tube may, however, include the distal tip of the catheter. This means that the catheter terminates at the most distal end of the tube. In this case, the catheter does not comprise any further entity extending further distally from the tube. The entire distal end region of the tube may include the reinforcement. In this case, the reinforcement may define/characterize the distal end. Specifically, the area in which the reinforcement is provided in the tube wall may be regarded as the area corresponding to the distal end region of the tube. It may be defined that other parts of the tube than the distal end region of the tube are free of the (said) reinforcement. The distal tip of the catheter may include a (e.g. rotatable) tip supported/borne by the distal end region of the tube. The distal end region of the tube does not comprise the outermost distal end (tip) of the catheter, but the (e.g.) rotatable tip supported/borne by the distal end region of the tube represents a distal tip of the catheter and is, thus, further distal than the most distal end of the tube. The distal end region of the tube comprises a reinforcement so as to reinforce the distal end region of the tube. Accordingly, the reinforcement is configured to reinforce the distal end of the tube. The reinforcement may define the distal end region of the tube. As such, the distal end region of the tube may represent the part of the tube which is reinforced by the reinforcement. The distal end region may comprise, throughout the distal end region, the reinforcement and may, accordingly, be free of sections having no reinforcement. According to disclosure, the distal end region of the tube has a reinforcement, and the reinforcement renders the distal end region of the tube sufficiently stiff/strong/stable. Hence, the tube may extend to the distal tip of the catheter, according to embodiment (a). Accordingly, the distal tip of the catheter may be continuous with (e.g. integral with) the remaining tube. If the distal tip of the catheter includes an e.g. rotatable tip, the distal end region of the tube and in particular the reinforcement comprised therein may support/bear the (rotatable) tip, according to embodiment (b). Accordingly, the distal end region of the tube serves as support for the (rotatable) tip. No separate entity serving as support/bearing may be needed. According to the disclosure, the distal end region of the tube is reinforced and, by way of the reinforcement, allows to replace (spare) entities that may have been added separately to the tube. Otherwise, a separate entity representing the distal tip of the catheter may be connected to the distal end region of the tube, such entity being more robust or stiffer than the distal end region of the tube. By reinforcing the distal end region of the tube, however, such separate additional entity may be omitted. The strength of the distal end region of the tube may be increased by way of the reinforcement. This may improve torsional strength and prevent from kinking of the tube. More specifically, torque and kink resistance may be improved. Further, a distal end of the disclosure may be beneficial in tortuous anatomies. E.g. the distal end may allow for improved bendability. If a rotatable tip forms the distal tip of the catheter, no additional stationary entity (e.g., a stator) forming the counterpart for the rotatable tip may need to be added to the distal end of the tube. Rather, by way of a reinforcement of the distal end of the tube, the distal end of the tube may be stiff and strong enough so as to serve as support/bearing/counterpart for the (rotatable tip), i.e. as a stationary entity. Accordingly, due to the reinforcement, the distal end of the tube may replace a separate entity that is usually fixed (e.g. glued) distally to the distal end of the tube. Accordingly, such separate or additional entities may be omitted. The distal end of the tube and/or distal tip of the catheter may be free of additional, separate entities, thereby improving manufacturability, reducing waste, and improving sustainability. Additional entities may be made of metal, for example. Instead of metal, the reinforcement may comprise a reinforcing material different from metal, such as the usual tube material or a fiber. Accordingly, metal may not be needed or less metal may be needed for the manufacture of the tube. This may be beneficial in terms of sustainability. The tube wall may comprise flexible material. Flexible material for the tube may be e.g. silicone, Latex, PTFE, vinyl, nylon, and/or polyurethan (PU). The catheter may be for vascular applications, in particular for thrombectomy and atherectomy applications. Accordingly, the catheter may form part of thrombectomy and atherectomy systems. The rotatable tip is rotatable relative to the distal end of the tube, in particular relative to the reinforcement. Accordingly, the rotatable tip rotates relative to the distal end of the tube. If the rotatable tip is made of a different material than the tube and/or the reinforcement, materials for the rotatable tip and for the tube may be chosen so as to minimize frictional loss during rotation of the rotatable tip relative to the distal end. During manufacture, the distal tip of the catheter is, in case of embodiment (a), a single piece and/or continuous with the tube. Accordingly, manufacturing steps may be reduced, if the tube including the distal tip of the catheter may be manufactured in less steps. Also, in embodiment (b), only the rotatable tip may need to be added to the tube for the catheter to be finalized. No separate support or counterpart for the rotatable tip, namely no additional stationary part, may need to be mounted distally to the distal end of the tube. As a result, the catheter of the disclosure may be advantageous relative to prior art catheters as regards manufacture, sustainability, and/or simplicity. Generally, the distal direction is defined as the direction away from or farthest from the user (e.g. surgeon/clinician) and towards the patient, whilst the proximal direction is defined as the direction from the patient towards the user (e.g. surgeon/clinician). The longitudinal direction is defined as the distal direction. Optionally, the reinforcement comprises at least one of a braiding, a coiling, a stiffer material and a larger (wall) thickness. Optionally, the reinforcement comprises the coiling comprising a coil wound in the longitudinal direction. The coiling may include a wire/fiber helically extending along at least a part of the tube. Optionally, the reinforcement comprises one or more fibers. The reinforcement may be used to strengthen the tube and to make it stiffer, while maintaining flexibility. The coiling may be preferable in terms of torsion stiffness and bending stiffness. Alternatively or additionally, the reinforcement may comprise one of the following reinforcing materials: PEEK, KEVLAR, carbon fiber, stainless steel-nitinol wire, fiberglass, Polyethylene naphthalate (PEN), PET, Nylon, Polyurethane, Pebax, Ultra-high weight molecular polyethylene (UHWMPE). Such materials are suitable to convey stiffness to the distal end region of the tube and, thus, to reinforce the distal end region of the tube. The reinforcing material may be within the (wall of the) tube or may be provided on the outer surface of the tube, e.g. as a coating. The reinforcement may additionally or alternatively be thicker than the remaining tube, optionally made of the same material as a non-reinforced region of the tube. For example, by increasing the thickness of the wall of tube, the distal end region of the tube becomes stiffer than the remaining tube or at least than the immediately adjacent tube section. In one embodiment, a braiding may be provided outside the distal end of the tube (e.g. also in the remaining tube). In this case, a reinforcement of the disclosure is comprised (only) in the distal end of the tube and is stiffer than the braiding outside the distal end of the tube. The reinforcement may be configured such that the stiffness of the tube increases gradually towards the proximal end. This may provide for simplified manufacture. Also this may be advantageous compared to an abrupt change of the stiffness as it may help to avoid occurrence of kinks in the proximal part of the tube (having no reinforcement). Optionally, the reinforcement is integral with the tube, i.e. the reinforcement and the tube are integrally formed. Put differently, the reinforcement may be integrated into the tube. By integrating the reinforcement into the tube, there may be a stronger link and connection between the reinforcement and the remaining tube, so that a basically single piece tube is obtained. Also, manufacture may be simplified in that during manufacture of the remaining tube, the reinforcement is simultaneously included. Optionally, the reinforcement is present/provided at least on opposite sides of the tube wall and/or has a cylindrical section, optionally the cylindrical section corresponding to a part of a cylinder formed by the cylindrical tube wall. The reinforcement may have a cylindrical section, in particular cylindrical to the effect that its shape corresponds to a part of the cylinder formed by the cylindrical tube wall. Put differently, a part of the cylindrical tube wall may have a (coaxial/concentric) cylindrical reinforcement. Optionally, the reinforcement may be present at least on opposite sides of the tube, if the reinforcement does not have a cylindrical section. The reinforcement on at least two opposing sides of the tube wall may allow for sufficient strength and reinforcement of the tube. Optionally, the reinforcement has a protruding section protruding radially outwards from the tube. The protruding section may be at the outermost distal end of the tube and optionally, the reinforcement may (additionally) be provided proximal to the protruding section. The protruding section may support bearing of the rotatable tip. Put differently, the protruding section may at least partially serve as a bearing. For example, the protruding section may serve as an abutment surface for the rotatable tip. Specifically if the reinforcement is additionally provided proximal to the protruding section, the support of the rotatable tip can be improved further. Alternatively, the reinforcement includes a protruding section protruding radially outwards from the tube, wherein the protruding section is proximal to the outermost distal end of the tube. In this embodiment, the reinforcement is (additionally) provided proximal to the outermost distal end of the tube. Optionally, the most distal end of the tube is provided with a reinforcement and/or the reinforcement is provided proximal to the protruding section. In this embodiment, the reinforcement extends proximally relative to the protruding section, which is also helpful in connection with the desired stiffness of the tube. In such embodiments, the reinforcement may (additionally) be provided distal to the protruding section. In one embodiment, the distal end of the tube may comprise a converging section converging at least partially radially inwards from the cylindrical tube wall. Specifically in the embodiment (a), the converging section may form the distal end region of the catheter. Optionally, the reinforcement is present/provided only in the distal end region of the tube, so that the remaining tube (proximal to the distal end region of the tube) is free of said reinforcement. Optionally, the reinforcement is continuous between the proximal end and the distal end region of the tube. The tube may comprise another, second reinforcement anywhere, wherein the (first) reinforcement is only provided in the distal end region. Alternatively, the (first) reinforcement of the distal end may extend along the entire tube, from the distal end towards the proximal end, with increasing strength in the distal direction. It is conceivable that the tube has a (second) reinforcement other than the (first) reinforcement anywhere in the tube, optionally except for in the distal end region of the tube. For example, the other (second) reinforcement may be a braiding, wherein the braiding extends from the proximal end distally, excluding the distal end region of the tube and/or catheter. Optionally, the reinforcement has a reinforcing material having a higher stiffness than the stiffness of the tube material. By doing so, the material as such serves as stiffener and increases the stiffness of the distal end region, so that the distal end region is appropriately reinforced. Optionally, the reinforcement is embedded within the tube wall and/or is encapsulated by the tube wall. In other terms, the reinforcement may be buried within the tube wall. This means that the outer surface of the distal end region of the tube may be made of tube material, not of reinforcing material. In these embodiments, the reinforcement may be integral with the tube. Accordingly, the outer surface of the tube may be continuous and continuously made of tube wall material. Specifically, the outer surface of the tube may be continuous and smooth without a transition in the material on the outer surface. This may facilitate smooth operation in that the tube is, during a procedure, not prone to attaching to or stopping at the vessel wall. Optionally, the reinforcement strength increases from a proximal region towards a distal region of the reinforcement. Accordingly, the reinforcement (strength) gradually increases from the proximal to the distal direction. This may support smooth operation in that the transition from a non-reinforced part of the tube to a reinforced distal end of the tube is gradual and supports navigation and guidance thereof through the vasculature. The distal end region of the tube may comprise at a side of the tube (i.e. perpendicular to the longitudinal direction) at least one window, optionally two windows located at opposite sides of the cylindrical tube wall, i.e. opposite to each other. The window(s) at the side(s) in the distal end region of the tube may serve as window for allowing for aspiration, namely aspiration of material removed from the vessel walls. Two windows on opposite sides of the cylindrical tube may help to support fast and reliable aspiration. The windows may be within the reinforcement, which may ensure that the windows are sufficiently strong and stable. Optionally, the outermost distal end of the tube and/or the distal tip of the catheter comprises an opening directed in the longitudinal (distal) direction. Such opening at the distal tip of the tube may correspond to an opening at the distal tip of the catheter, in particular in connection with embodiment (a). Such opening may serve as an opening for a guidewire, the guidewire extending along the catheter, in the center of the catheter and entering/exiting the catheter through the opening at the distal tip of the tube/catheter. The opening can be central to the catheter when viewed in a cross-section perpendicular to the longitudinal direction. Optionally, the rotatable tip is at least partially distal to the distal end region of the tube and is connected to the distal end region of the tube. As such, the rotatable tip may form the distal tip of the catheter. The rotatable tip may comprise a connecting section for connecting to the distal end of the tube. Specifically, the distal end of the tube may comprise the reinforcement, so that the connecting section connects to the reinforcement of the tube. By doing so, the rotatable tip has a stiffer counterpart which ensures reliable and accurate rotation of the rotatable tip. In other terms, the rotatable tip has a sufficiently stiff bearing. Optionally, the rotatable tip is held/borne/supported by the distal end region of the tube, in particular by the reinforcement during rotation, so that the rotatable part rotates against the distal end region of the tube, in particular against the reinforcement. The reinforcement may be strong enough so as to allow for stable rotation of the rotatable tip. Optionally, the connecting portion of the rotatable tip is at least partially received inside the lumen of the tube. Alternatively or additionally, the connecting section at least partially surrounds an outer surface of the distal end, optionally comprising the reinforcement. Hence, the rotatable tip may be inside or outside of the distal tube, when viewed in a cross-section perpendicular to the longitudinal direction. By doing so, the rotatable tip may have a strong support by way of the distal end region of the tube. In particular, the reinforcement in the distal end of the tube and the connecting portion may run in parallel along the longitudinal direction, at least partially, so as to provide for appropriate guidance of the rotatable tip by the distal end of the tube. Also the rotatable tip may have a window and/or an opening, as described in connection with the distal end region of the tube above. Optionally, the connection between the distal end region of the tube and the rotatable tip is indirect, optionally via a low-friction material. Such low-friction material may be PTFE, PEEK, or ultra-high molecular weight polyethylene (UHMWPE). The low friction material may be in the form of a ring shape. Specifically, the connection of the rotatable tip and the distal end of the tube may be along the low friction material. The distal end of the tube comprises the reinforcement where the connection relative to the rotatable tip is established. By way of the low friction material, the friction between the rotatable tip and the stationary distal end region of the tube may be reduced, which increases the efficiency and accuracy as well as the reliability during use, i.e. during rotation of the rotatable tip relative to the tube. The present disclosure is also directed to a catheter having a flexible, longitudinal tube, the tube having a cylindrical tube wall defining a cylindrical lumen, the tube comprising a proximal end a distal end. The distal end of the tube comprises a reinforcement so as to reinforce the distal end of the tube and comprises at least one window or opening through the reinforcement. The advantages have been explained above. Further, embodiments in this regard are evident from the above and the window or opening through the reinforcement are combinable with any of the features explained above. Specifically, the catheter of claim 19 may be defined by the features of claims 1 to 20. The disclosure is also directed to a thrombectomy or atherectomy system having a catheter of the disclosure. The system further comprises a rotatable helix extending through the lumen and to the distal end. The rotatable helix is connected to the outermost distal end of the tube, in particular the catheter distal tip, or is connected to the rotatable tip. Accordingly, the helix may be rotated so as to drive the rotatable tip, namely so as to rotate the rotatable tip. The present disclosure is also directed to a manufacturing method for any of the catheters described herein. The reinforcement may be provided in a distal end of a mold, the distal end of the mold corresponding to the distal end of the tube. The reinforcement is provided in the distal end of the mold before the tube material is injected into the mold. The reinforcement is embedded within the tube material after molding. Optionally, the method comprises, in a subsequent step, removal of tube material or removal of a part of the reinforcement from the tube so as to form an opening at the distal tip of the tube and/or a window at a side of the tube at the distal end of the tube. Hence, the window or the opening is formed after the reinforcement has been integrated or integrally formed with the tube material. As such, the reinforcement is integrally formed with the tube, i.e. the reinforcement and the tube material are integrated. Brief Description of the Drawings Fig. 1a schematically depicts a cross-sectional side view of a catheter, according to one or more embodiments shown and described herein; Fig. 1b schematically depicts a side view of the catheter of Fig. 1a, wherein a distal end of the tube forms the distal tip of the catheter, according to one or more embodiments shown and described herein; Fig. 1c depicts an enlargement of a part of a tube wall 2a of the distal end of a tube of Fig. 1a, according to one or more embodiments shown and described herein; Fig. 2a has three parts and schematically depicts a cross- section of a catheter of the disclosure, wherein the distal tip of the catheter includes a rotatable tip; Fig. (1) refers to a first embodiment; Fig. (2) refers to a second embodiment; and Fig. (3) refers to a third embodiment; Fig. 2b schematically depicts a cross-section of a distal end of a tube without a rotatable tip, according to one or more embodiments shown and described herein; Fig. 3 schematically depicts a distal portion of a catheter, according to one or more embodiments shown and described herein; Fig. 4 schematically depicts a cross-section of a distal portion of a catheter, according to one or more embodiments shown and described herein; Fig. 5 schematically depicts a distal portion of a catheter, according to one or more embodiments shown and described herein; Fig. 6 schematically depicts a thrombectomy or atherectomy system, according to one or more embodiments shown and described herein; Fig. 7 schematically depicts a mold for forming a catheter, according to one or more embodiments shown and described herein; Detailed Description Fig. 1 depicts a catheter 1 having a flexible, longitudinal tube 2 extending in the longitudinal direction L. The catheter 1 has a distal end region 9 terminating distally at the distal tip 9a of the catheter. The distal tip 9a is the outermost end of the catheter 1 in the longitudinal direction L, i.e. in the distal direction. The tube 2 has a cylindrical tube wall 2a, which comprises tube material and is substantially made of tube material. The cylindrical tube wall 2a defines a cylindrical lumen 3, i.e. surrounds a cylindrical lumen 3. Fig. 1a shows the tube 2 and its proximal end 4 (indicated in Fig. 1 and pointing further proximally, i.e. further to the left side, than what is depicted in Fig. 1) and its distal end region 5, along the longitudinal direction L. The tube 2 is continuous between the proximal end 4 (end in the proximal direction P) and the distal end 5 (end in the distal direction D), i.e. has no interruptions inbetween. The distal end region 5 is the region proximal to the most distal end 5a of the tube 2, as indicated in Fig. 1a. In the distal end region 5, the tube comprises a reinforcement 6 to reinforce the distal end region 5 of the tube 2. Specifically and with reference to Fig. 1b, the proximal end of the distal end region 5 of the tube 2 may be defined by the proximal end (termination) 6-1 of the reinforcement 6. The reinforcement 6 may, in the distal/longitudinal direction L, extend toward the outermost distal end 5a of the tube 2, representing the distal end (termination) 6-2 of the reinforcement. In Figs. 1a and 1b, a first embodiment of the present disclosure is shown, namely the embodiment (a), wherein the distal end region 5 of the tube 2 includes the distal end region 9 of the catheter 1. Specifically, Fig. 1a shows that the outermost distal end 5a of the tube 5 corresponds to the distal tip 9a of the catheter 1. The reinforcement 6 is a coiling 6’’ and includes a helically wound coil (wire). The tube 2 may comprise in this embodiment a braiding 22 outside the distal end region 5. The part of the tube 2 having the coiling 6’’ is stiffer than the part of the tube 2 further in the proximal direction P and having less stiff reinforcement (e.g., braiding 22). Stated another way, the distal end region 5 having the reinforcement 6 has a greater stiffness and/or strength than the proximal end 4 having the braiding 22. In Fig. 1b, the distal end region 5 is indicated, the reinforcement 6 extending throughout the entire distal end region 5. The reinforcement 6 has a proximal end 6-1 of the reinforcement, i.e. the end of the reinforcement in the distal direction P, and a distal end 6-2 of the reinforcement, which ends at the outermost distal end 5a of the tube 2. The distal end 6 extending between ends 6-1 and 6-2 may have a length of about 40 to 60 mm, optionally of about 50 mm in the longitudinal direction L. The distal end region 5 of the tube 2 may include a converging section 6c of the reinforcement 6, converging at least partially radially inwards from the cylindrical tube wall 2a. Such converging section 6c may assist in navigation of the catheter through a vessel. As shown in Figs. 1a and 1b, the converging section 6c converges from the cylindrical part of the tube wall 2a radially inwards. In the view shown in Fig. 1a, the converging section 6c converges, while it includes a central opening 8. In the view of Fig. 1b, which can be regarded as a view from the top, whilst Fig. 1a shows a side view, the converging section 6c is shown to converge more. The reinforcement 6 may include PEEK, KEVLAR or carbon fibers. The reinforcement 6 may be integral with the tube 2 in the distal end region 5 of the tube, e.g. embedded. The tube wall 2a may additionally comprise a braiding 22, wherein the braiding 22 is not present in the distal end region of the tube 5, but only present further proximally, in particular in the proximal end 4 of the tube 2. The reinforcement 6 is present only in the distal end region 5 of the tube 2, while the remaining tube 2, proximal to the distal end region 5, is free of this same reinforcement 6. However, the tube 2 is not necessarily entirely free of any reinforcement outside the distal end region 5 of the tube. For example, outside of the distal end region 5 of the tube, the tube 2 may comprise another (type of) reinforcement, such as braiding 22, or some other reinforcement. By way of the reinforcement 6 and specifically the reinforcing material, the stiffness of the tube 2 in the distal end region 5 is higher than the stiffness of the remaining tube 2, in particular of the remaining tube material. The reinforcement 6 is embedded within the tube wall 2a, so that the tube 2 is continuous from the proximal end 4 towards the distal end region 5, in particular the outermost distal end 5a. The reinforcement strength increases from a proximal region 6-1 towards a distal region 6-2 of the reinforcement 6, as indicated in Fig. 1b. In Fig. 1c, the individual coils of the coiling 6’’ as shown in Fig. 1a may have a smaller pitch e.g. at the outermost distal end of the tube 5a than towards the proximal end 6-1 of the reinforcement 6. An example of such pitch is shown in Fig. 1c. The pitch pi-p at the proximal side of the reinforcement 6’’ is larger than the pitch pi-d at the distal side of the reinforcement 6’’. Hence, the strength provided by the reinforcement 6 increases from the proximal P to the distal D direction. In Figs. 1a and 1b, two windows 7 on opposite sides of the cylindrical tube wall 2 are shown. An opening 8 at the outermost distal end, i.e. the distal tip 9 of the catheter 1 is shown in Fig. 1a. Fig. 1a also shows a helix 12, the helix 12 abutting, at the distal end region 5, the converging section 6c of the reinforcement. The helix 12 is freely rotatable within the catheter 1 shown in Figs. 1a and 1b. Figs. 2a and 2b are directed to the embodiment (b), wherein the distal end region 9 of the catheter 1 includes a rotatable tip 10, which is supported/borne by the distal end region 5, the reinforcement 6 comprised in the distal end region 5 of the tube 2. In other words, instead of the most distal end 5a of the tube 2 forming the distal tip 9a of the catheter 1 (as in embodiment (a)), the rotatable tip 10 forms the distal tip of the catheter 1. Specifically, the rotatable tip 10 of the catheter 1 is supported/borne by the reinforcement 6 of the distal end region 5. As an example, the reinforcement 6 is a reinforcing material 6’’’. The reinforcing material 6’’’ renders the tube 2 stiffer in the distal end region 5 of the tube that the braiding 22 proximal to the distal end region 5 of the tube 2. Fig. 2a shows a rotatable tip 10 at least partially distal to the distal end region 5 of the tube 2 and connected to the distal end region 5 of the tube 2. The rotatable tip 10 comprises a connecting section 10a for connecting to the distal end region 5 of the tube 2, more specifically to the reinforcement 6. The connecting section 10a of the rotatable tip 10 is at least partially inside the lumen 3 of the tube 2 or at least partially surrounds an outer surface 5b of the distal end region 5. Specifically, the connecting section 10a extends at least in part parallel to the reinforcement 6. The rotatable tip 10 may be held and biased in the proximal direction P by way of the helix 12. In Figs. (1) and (2) of Fig. 2a, the connecting section 10a of the rotatable tip 10 extends at least partially in the longitudinal direction L. Parallel to the longitudinal direction L, a cylindrical section 6a of the reinforcement is provided. The cylindrical reinforcement 6a supports and holds, by means of the reinforcement, the rotatable tip 10, in particular the connecting section 10a of the rotatable tip 10. In Fig. (2) of Fig. 2a, the reinforcement 6 also comprises a protruding section 6b of the reinforcement. The protruding section 6b protrudes radially outwards from the tube 2, wherein the protruding section 6b is proximal to the outermost distal end 5a of the tube 5. The outermost distal end 5a of the tube 2 may also be provided with the reinforcement 6, see Fig. (3) of Fig. 2a. The reinforcement 6 is provided proximal to the protruding section 6b in Fig. (2) of Fig. 2a. Hence, distal or proximal to a protruding section 6b, in particular a protruding section 6b protruding radially outwards from the tube 2, reinforcement 6 may be provided. In Fig. (2) of Fig. 2a, the protruding section 6b protruding radially outwards from the tube is provided at the outermost distal end 5a of the tube 2. The reinforcement 6b is provided at least partially proximal to the protruding section 6b. The reinforcement proximal to the protruding section 6b is in the form of a cylindrical section 6a. In Fig. (1) of Fig. 2a, the reinforcement 6 has a cylindrical section 6a. More specifically, the reinforcement 6 can be regarded as a cylinder 6a. In the three Figures of Fig. 2a, the rotatable tip 10 has two windows 7’ at opposite sides of the rotatable tip 10. Also, the rotatable tip 10 has an opening 8' at the distal tip 9 for receiving a guidewire (not shown). In the proximal part of the tube wall 2a, a braiding 22 may be provided. The reinforcement 6 in the embodiment of Fig. 2a and 2b is a reinforcing material 6’’’, such as PEEK, KEVLAR, carbon fiber, stainless steel-nitinol wire, fiberglass, Polyethylene naphthalate (PEN), PET, Nylon, Polyurethane, Pebax, Ultra- high weight molecular polyethylene (UHWMPE). In the drawings of Fig. 2a, the helix 12 is shown. The helix 12 extends along the tube 2 and is attached to the rotatable tip 10 at the distal tip of the catheter 9. Rotation of the helix 12 imparts rotation to the rotatable tip 10. Hence, the rotatable tip 10 rotates around the longitudinal direction L. With reference to Fig. 2b, the connecting section 10a between the distal end region 5 of the tube and the rotatable tip 10 provides for connection. Specifically, the reinforcement 6 may comprise a low friction material 11. In Fig. 2b, where the tube 2 without the rotatable tip 10 is shown, the low friction material 11 is provided in a ring shape. Substantially, the low friction material 11 (e.g. PTFE, PEEK, or ultra-high molecular weight polyethylene (UHMWPE)) forms a ring which abuts distally the protruding section 6b. Hence, the rotatable tip 10 may be in direct contact with the low friction material 11, so that friction during rotation of the rotatable tip relative to the tube 2 can be reduced. In one embodiment, the reinforcement 6 may comprise a braiding 6’. The remaining tube 2 is free of a braiding 22. This is reflected in Fig. 3 for an embodiment (a), but also applies for embodiment (b). In Fig. 3, the braiding 6’ is provided in the distal end region 5 of the tube. Hence, by way of the braiding 6’, the distal end region 5 of the tube 2 is rendered stiffer than the part of the tube 2 proximal to the distal end region 5. In an embodiment, the reinforcement 6 comprises a thickened tube wall (6’’’’), see Fig. 4. This is reflected in Fig. 4 for an embodiment (a), but also applies for embodiment (b). In Fig. 4, the thickness th of the tube wall 2a increases (e.g. gradually) in the distal end region 5 of the tube in the distal direction D. Thickness th-p is smaller than the thickness th-d. For example, th-p may be half of th-d, which means that the thickness of the tube wall 2a is doubled towards the distal end 6-2 of the reinforcement 6. In Fig. 5, a catheter 1 including the rotatable tip 10 is shown. The tube 2 has a reinforcement 6, wherein, onto the reinforcement 6, the rotatable tip 10 is supported. Through the window 7' in the rotatable tip 10, the helix 12 is visible. The rotatable tip 10 forms, at its distal tip, the distal tip 9 of the catheter. Hence, the rotatable tip 10 contacts an outer surface 5b of the distal end region 5. The guidewire 14 extends through the catheter 1 and exits via the window 8'. The guidewire 14 and the catheter 1 extend in the longitudinal direction L. Fig. 6 shows an atherectomy or thrombectomy system 13. The system 13 comprises the catheter 1, wherein the distal tip 9 of the catheter 1 is shown. The guidewire 14 emerges from the catheter 1. At its proximal end, the catheter 1 emerges from the handle 15. The handle 15 can be held by the hand of a surgeon during operation. The handle 15 includes a motor 16 for driving the helix 12 and the rotatable tip 10, i.e. to rotate the rotatable tip 10. The system further comprises a control unit 17 for controlling the rotation of the helix 12. I embodiments a footswitch 18 and/or a collection bag 19 for collecting removed material may be included. During manufacture of a catheter 1, the reinforcement 6 is provided in a distal end of a mold 20 before the tube material is injected into the mold. Fig. 7 shows a mold 20 comprising an upper mold and a lower mold, wherein, when the mold is closed, the reinforcement is placed in a distal end 21 of the mold 20. Accordingly, the reinforcement 6 is present in a distal end region 5 of the tube 2 as manufactured. The reinforcement 6 is positioned in the distal end 21 of the mold 20 before tube material is injected into the mold 20. Optionally, a stem-like part of the mold may be applied to keep material away from occupying a central cavity along the longitudinal direction of the tube 2, so as to form the lumen 3. In a subsequent step, tube material and/or reinforcement 6 may be removed from the tube 2 so as to form an opening 8 at a distal tip 9 of the catheter or a window 7 at a side of the tube 2 at the distal end region 5 of the tube. The material can be removed by way of laser cutting or by stamping, for example. Reference signs 1 catheter 2 tube 2a tube wall 3 lumen 4 proximal end of tube 5 distal end region of tube 5a (outer)most distal end of tube 5b outer surface of distal end 6 reinforcement 6’ braiding (Fig. 3) 6’’ coiling (Fig. 1a, 1c) 6’’’ reinforcing material (Fig. 2a) 6’’’’ thickened tube wall (Fig. 4) 6a cylindrical section of reinforcement 6b protruding section of reinforcement 6c converging section of reinforcement 6-1 proximal end of reinforcement 6-2 distal end of reinforcement 7, 7’ window 8, 8’ opening 9 distal end region of catheter 9a distal tip of catheter 10 tip, optionally rotatable (rotor) 10a connecting section 11 low friction material 12 helix 13 system 14 guidewire 15 handle 16 motor 17 control unit 18 foot switch 19 collection bag 20 mold 21 distal end of mold 22 braiding proximal to the distal end region of the tube pi-p pitch of coiling at proximal end pi-d pitch of coiling at distal end th-p wall thickness at proximal end th-d wall thickness at distal end L longitudinal direction P proximal direction D distal direction

Claims

Claims 1. A Catheter (1) comprising: a longitudinal tube (2) and a distal tip (9a), wherein the tube (2) comprises a cylindrical tube wall (2a) extending between a proximal end (4) and a distal end region (5) having a most distal end (5a) along a longitudinal direction, the cylindrical tube wall (2a) defining a cylindrical lumen (3) and formed at least partially of a flexible material, the distal end region (5) of the tube comprises a reinforcement (6) to reinforce the distal end region (5) of the tube (2) relative to at least a part of the tube (2) proximal to the distal end region (5) of the tube (2), optionally relative to the proximal end (4) of the tube (2), and (a) the distal end region (5) of tube (2) represents the distal end region (9) of the catheter (1), such that the distal end region (9) of the catheter (1) comprises the reinforcement (6), or (b) the distal end region (9) of the catheter (1) includes an optionally rotatable tip (10) borne by the distal end region (5) of the tube (2), wherein the reinforcement (6) supports bearing of the tip (10) at the distal end region (5) of the tube (2).

2. The Catheter of claim 1, wherein the reinforcement (6) comprises a braiding (6’), a coiling (6’’), a reinforcing material (6’’’) and/or a larger thickness (6’’’’) of the tube wall (2a).

3. The Catheter of claim 2, wherein the reinforcement comprises the coiling (6’’) and the pitch (pi-p, pi-d) of the coiling increases from the distal end region of the tube (2) towards proximal end of the tube and/or the thickness (th-p, th-d) of the tube wall (2a) increases from the proximal end (4) of the tube (2) towards the distal end region (5) of the tube (2).

4. The Catheter of any of the preceding claims, wherein the stiffness of the tube (2) increases, due to the reinforcement (6), from the proximal end (4) to the distal end region (5), optionally gradually.

5. The Catheter of any of the preceding claims, wherein the reinforcement (6) is integral with the tube (2).

6. The Catheter of any of the preceding claims, wherein the reinforcement (6) is present at least on opposite sides of the tube wall (2a) and/or has a cylindrical section (6a), optionally the cylindrical section (6a) corresponding to a part of a cylinder formed by the cylindrical tube wall (a).

7. The Catheter of any of the preceding claims, wherein the reinforcement (6) has at least one protruding section (6b) protruding radially outwards from the tube (2), wherein the protruding section (6b) is at the most distal end (5a) of the tube, optionally wherein at least a part of the reinforcement (6) is provided proximal to the protruding section (6b).

8. The Catheter of any of the preceding claims 1 to 4, wherein the reinforcement has at least one protruding section (6b) protruding radially outwards from the tube (2), wherein the protruding section (6b) is at the most distal end (5a) of the tube, optionally wherein the outermost distal end of the tube (5a) is provided with the reinforcement (6) and/or the reinforcement (6) is provided proximal to the protruding section (6b).

9. The Catheter of any of the preceding claims, wherein the reinforcement (6) comprises a converging section (6c) converging at least partially radially inwards from the cylindrical tube wall (2a).

10. The Catheter of any of the preceding claims, wherein the reinforcement (6) is present only in the distal end region (5) of the tube (2) and the remaining tube (2) is free of said reinforcement (6), or wherein the reinforcement (6) is continuous between the proximal end (4) and the distal end region (5) of the tube (2).

11. The Catheter of any of the preceding claims, wherein the reinforcement material has a higher stiffness than the stiffness of the tube material.

12. The Catheter of any of the preceding claims, wherein the reinforcement (6) is embedded within the tube wall (2a) and/or is encapsulated by the tube wall (2a).

13. The Catheter of any of the preceding claims, wherein the reinforcement strength increases from a proximal region (6-1) towards a distal region (6-2) of the reinforcement (6).

14. The Catheter of any of the preceding claims, wherein the distal end region (5) comprises at a side at least one window (7), optionally two windows (7) located at opposite sides of the cylindrical tube wall (2a).

15. The Catheter of any of the preceding claims, wherein the outermost distal end (5a) of the tube comprises an opening (8).

16. The Catheter of any of the preceding claims, wherein the rotatable tip (10) is at least partially distal to and connected to the distal end region (5) of the tube.

17. The Catheter of claim 16, wherein the rotatable tip (10) comprises a connecting section (10a) for connecting to the distal end region (5) of the tube.

18. The Catheter of claim 16 or 17, wherein the connecting section (10a) of the rotatable tip (10) is at least partially received inside the lumen (3) of the tube (2) or at least partially surrounds an outer surface (5b) of the distal end region (5), optionally comprising the reinforcement (6).

19. The Catheter of any of claims 16 to 18, wherein the connection between the distal end region (5) and the rotatable tip (10) is indirect, optionally via a low friction material (11), further optionally PTFE or PEEK.

20. The Catheter of claim 19, wherein the low friction material (11) is provided in a ring-shape.

21. A Catheter (1) comprising a longitudinal tube (2), the tube (2) comprising a cylindrical tube wall (2a) extending between a proximal end (4) and a distal end region (5) having a most distal end (5a) along a longitudinal direction, the cylindrical tube wall (2a) defining a cylindrical lumen (3) and formed at least partially of a flexible material, wherein the distal end region (5) of the tube comprises a reinforcement (6) to reinforce the distal end region (5) of the tube and comprises at least one window (7) or opening (8) through the reinforcement (6).

22. Thrombectomy or atherectomy system having a catheter of any of the preceding claims 1 to 21, wherein the system comprises a rotatable helix (12) extending through the lumen (3) and to the distal end region (5).

23. Manufacturing method for a catheter, optionally of the catheter of any of the preceding claims 1 to 20, wherein a reinforcement (6) is provided in a distal end (21) of a mold (20) before tube material is injected into the mold (20).

24. The Manufacturing method of claim 23, wherein the method comprises in a subsequent step removal of tube material and/or reinforcement (6) from the tube so as to form an opening (8) at the distal tip (9) of the catheter (1) or of the outermost distal end (5a) of the tube (2) and/or a window (7) at a side of the distal end region (5) of the tube.