Delivery system

Abstract

The present application relates to a delivery system in which an inner catheter (2000) is movably disposed within an axial lumen of an outer catheter (1000). The inner catheter (2000) has a pushing inner catheter section (1100) and a curved inner catheter section (1200) along its axial direction. The diameter of the curved inner catheter section (1200) is larger than the diameter of the pushing inner catheter section (1100). A guidewire (2100b) is inserted into the guide lumen of the inner catheter (2000), and a puller wire (2200b) is connected to the curved inner catheter section (1200).

Description

TECHNICAL FIELD

[0001] The present application claims priority to Chinese Patent Application No. 202211527659.3 filed on December 1, 2022 under the title "Delivery System", the entire disclosure of which is incorporated herein by reference. BACKGROUND ART

[0002] The present application relates to the technical field of medical devices, in particular to a delivery system.

[0003] Transcatheter Aortic Valve Replacement (TAVR) is a procedure that uses the catheter of a delivery system to deliver a prosthetic aortic valve to the aortic root, fix and release it in place, and replace the native valve. TAVR is a widely adopted technique in the field of treating valvular heart disease, and represents a groundbreaking advance in the minimally invasive treatment of aortic valve diseases. In the treatment of aortic valve diseases by TAVR, there is no need to open the patient's chest and stop the heart, so the patient will not suffer major trauma.

[0004] Most catheters of existing delivery systems used in TAVR procedures cannot be actively steered. To pass through the aortic arch, they need to bend passively under the reaction force from the inner wall of the blood vessel. However, some damage may occur to the inner wall of the blood vessel during this process, which may cause vascular complications. Furthermore, since such catheters cannot be actively steered, extremely difficult operations are required for passing through the annulus and coaxial release in the subsequent TAVR stage, which affects the release and anchoring of the valve. Therefore, how to realize the active steerability of the catheter of the delivery system remains a difficult problem that is urgently to be solved. SUMMARY OF THE INVENTION

[0005] Delivery systems are proposed in various embodiments disclosed herein. Hereafter, a delivery system is provided comprising: an outer catheter having an axial lumen; an inner catheter having a guide lumen, wherein the inner catheter is movably disposed inside the axial lumen of the outer catheter, and the inner catheter has a pressing inner catheter section and a curved inner catheter section along the axial direction, the distal end of the pressing inner catheter section being connected to the proximal end of the curved inner catheter section, and the diameter of the curved inner catheter section being greater than the diameter of the pressing inner catheter section; a guide wire inserted into the guide lumen of the inner catheter; and a traction wire connected to the curved inner catheter section.

[0006] In one embodiment, the distal end of the traction wire is connected to the distal end of the curved inner catheter section.

[0007] In one embodiment, the curved inner catheter section is provided with a traction fixing member, and the traction wire is connected to the curved inner catheter section via the traction fixing member.

[0008] In one embodiment, the traction fixing member has a first internal bore that communicates with the guide lumen.

[0009] In one embodiment, the traction fixing member is provided with a first wire attachment member, and the traction wire is connected to the first wire attachment member.

[0010] In one embodiment, the internal catheter has a traction lumen, and the traction wire is inserted into the traction lumen of the internal catheter.

[0011] In one embodiment, a bending-resistant support tube is provided inside the traction lumen.

[0012] In one embodiment, an internal catheter connecting segment is provided at the proximal end of the pressing internal catheter section, a wire exit port is provided at the internal catheter connecting segment, the wire exit port is in communication with the traction lumen, and the proximal end of the traction wire is drawn out from the wire exit port.

[0013] In one embodiment, the proximal end of the curved inner catheter section has a variable diameter segment connected to the distal end of the pressing inner catheter section, and the diameter of the variable diameter segment of the curved inner catheter section gradually decreases from the distal end to the proximal end.

[0014] In one embodiment, the curved inner catheter section is provided with a stent fixing member.

[0015] In one embodiment, the stent fixing member is provided at the proximal end of the curved inner catheter section, and the curved inner catheter section is connected to the distal end of the pressing inner catheter section via the stent fixing member.

[0016] In one embodiment, the stent fixing member is provided at the distal end of the curved inner catheter section.

[0017] In one embodiment, the curved inner catheter section has a first inner catheter segment and a second inner catheter segment along the axial direction, the distal end of the first inner catheter segment is connected to the proximal end of the second inner catheter segment via the stent fixing member.

[0018] In one embodiment, the stent fixing member has a second internal bore that communicates with the guide lumen.

[0019] In one embodiment, the stent fixing member has a stent fixing element.

[0020] In one embodiment, the curved inner catheter section has a flexible backbone and a flexible protective layer, the flexible backbone being located within the flexible protective layer.

[0021] In one embodiment, the flexible backbone has a backbone tube, and the wall of the backbone tube is provided with a bending auxiliary opening.

[0022] In one embodiment, the curved auxiliary opening is a linear opening, the curved auxiliary opening is arranged in the circumferential direction of the backbone tube, there are multiple curved auxiliary openings, and the multiple curved auxiliary openings are distributed along the axial direction of the backbone tube.

[0023] In one embodiment, the flexible protective layer comprises a flexible inner protective layer and a flexible outer protective layer, wherein the flexible outer protective layer is provided on the outer surface of the backbone tube and the flexible inner protective layer is provided on the inner surface of the backbone tube.

[0024] In one embodiment, the flexible backbone includes a plurality of rotatable elements distributed along the axial direction of the flexible backbone, and adjacent rotatable elements are articulated to each other.

[0025] In one embodiment, adjacent rotatable elements are rotatably connected to a fixed axis, and the multiple rotation axes of the multiple rotatable elements are parallel.

[0026] In one embodiment, the pressing inner catheter section has an inner catheter inner layer and an inner catheter outer layer, an inner catheter braid layer is disposed between the inner catheter inner layer and the inner catheter outer layer, and at least one of the guiding lumen and the traction lumen is formed inside the inner catheter inner layer.

[0027] In one embodiment, at least one internal catheter reinforcing element is positioned inside the inner layer of the internal catheter, between the guide lumen and the traction lumen.

[0028] In one embodiment, the outer catheter has a push outer catheter section and a curved outer catheter section along the axial direction, and the distal end of the push outer catheter section is connected to the proximal end of the curved outer catheter section.

[0029] In one embodiment, the distal end of the curved outer catheter section has a deformable segment including a straight cylindrical configuration and a tapered cylindrical configuration, and the deformable segment is configured to change between the straight cylindrical configuration and the tapered cylindrical configuration.

[0030] In one embodiment, the proximal end of the curved outer catheter section has a variable-diameter segment connected to the distal end of the push outer catheter section, and the diameter of the variable-diameter segment of the curved outer catheter section gradually decreases from the distal end toward the proximal end.

[0031] The details of one or more embodiments of the present application are set forth in the accompanying drawings and the description below. Other features, objects, and advantages of the present disclosure will be apparent from the description and drawings, as well as the appended claims. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] In order to more clearly describe the technology proposed in the present specification or the prior art, the accompanying drawings referred to in the following description of the embodiments or the description of the prior art are described below. Obviously, these drawings only show some embodiments of the present application, and a person of ordinary skill in the art can obtain other drawings in light of the drawings included in the present specification without creative efforts. [Figure 1] It schematically shows how an inner catheter according to some embodiments of the present application is steered. [Figure 2] It is a schematic diagram showing the structure of an outer catheter according to some embodiments of the present application. [Figure 3]This is a schematic diagram showing the structure of a delivery system according to several embodiments of the present application. [Figure 4] This is a schematic diagram showing the structure of a curved outer catheter section according to several embodiments of the present application. [Figure 5] Figure 4 is an enlarged view (I) of the curved lateral catheter section. [Figure 6] Figure 4 is another enlarged view (II) of the curved lateral catheter section. [Figure 7] This is a schematic diagram showing the structure of a backbone tube according to several embodiments of the present application. [Figure 8] This is a schematic diagram showing the structure of a backbone tube according to another embodiment of the present application. [Figure 9] This is a schematic cross-sectional view of a pressing inner catheter section according to several embodiments of the present application. [Figure 10] This is a schematic diagram showing the structure of an internal catheter connecting segment according to several embodiments of the present application. [Figure 11] This is a schematic diagram showing the structure of an internal catheter according to several embodiments of the present application. [Figure 12] Figure 11 is a schematic diagram showing that the inner catheter is in a bent configuration. [Figure 13] This is a schematic diagram showing the structure of a traction fixing member according to several embodiments of the present application. [Figure 14] This is a schematic diagram showing the structure of a stent fixing member according to several embodiments of the present application. [Figure 15] This is a schematic perspective view of an assembly of a traction fixing member, backbone tube, and stent fixing member according to several embodiments of the present application. [Figure 16] A schematic plan view of an assembly of a traction fixing member, backbone tube, and stent fixing member according to several embodiments of the present application is shown. [Figure 17] The operation of a delivery system according to several embodiments of this application is schematically shown. [Figure 18]The operation of a delivery system according to several embodiments of this application is schematically shown. [Figure 19] The operation of a delivery system according to several embodiments of this application is schematically shown. [Figure 20] The operation of a delivery system according to several embodiments of this application is schematically shown. [Figure 21] The operation of a delivery system according to several embodiments of this application is schematically shown. [Figure 22] This is a schematic diagram showing the structure of an internal catheter according to several other embodiments of the present application. [Figure 23] Figure 22 is a schematic diagram showing the internal catheter in a bent configuration. [Figure 24] Schematic perspective views of assemblies of traction fixation members, backbone tubes, and stent fixation members according to several other embodiments of the present application are shown. [Figure 25] A schematic plan view of an assembly of a traction fixing member, backbone tube, and stent fixing member according to several other embodiments of the present application is shown. [Figure 26] The operation of a delivery system according to several other embodiments of this application is schematically shown. [Figure 27] The operation of a delivery system according to several other embodiments of this application is schematically shown. [Figure 28] The operation of a delivery system according to several other embodiments of this application is schematically shown. [Figure 29] The operation of a delivery system according to several other embodiments of this application is schematically shown. [Figure 30] This is a schematic diagram showing the structure of an internal catheter according to several further embodiments of the present application. [Figure 31] Figure 30 is a schematic diagram showing the internal catheter in a bent state. [Figure 32] This is a schematic diagram showing the structure of a stent fixing member according to several other embodiments of the present application. [Figure 33]Schematic perspective views of assemblies of traction fixation members, backbone tubes, and stent fixation members according to several other embodiments of the present application are shown. [Figure 34] A schematic plan view of an assembly of a traction fixing member, backbone tube, and stent fixing member according to several other embodiments of the present application is shown. [Figure 35] The operation of a delivery system according to several embodiments of the present invention is schematically shown. [Figure 36] The operation of a delivery system according to several embodiments of the present invention is schematically shown. [Figure 37] The operation of a delivery system according to several embodiments of the present invention is schematically shown. [Figure 38] The operation of a delivery system according to several embodiments of the present invention is schematically shown. [Modes for carrying out the invention]

[0033] Embodiments of the present application are described below clearly and completely in conjunction with the accompanying drawings. Naturally, the embodiments described herein are only a portion, not all, of the possible embodiments of the present application. All other embodiments that a person skilled in the art could devise without creative effort in light of the disclosed embodiments are also considered to be within the scope of the present application.

[0034] To more clearly describe the structure of the delivery system proposed herein, the term “distal end” may be used to refer to the end away from the surgeon during surgery, and the term “proximal end” may be used to refer to the end closer to the surgeon during surgery. Unless otherwise defined, all technical and scientific terms used herein have the same meaning as that ordinarily understood by a person ordinary in the art to which this application pertains. The terms used herein are for the purpose of describing specific embodiments and are not intended to limit this application.

[0035] Referring to Figures 1 to 3, an embodiment of the present application provides a delivery system comprising an outer catheter 1000, an inner catheter 2000, a guidewire 2100b, and a traction wire 2200b. The outer catheter 1000 has an axial lumen, and the inner catheter 2000 has a guidewire 2100a. The inner catheter 2000 is movably positioned inside the axial lumen of the outer catheter 1000. The inner catheter 2000 has, along the axial direction, a pressing inner catheter section 2100 and a curved inner catheter section 2200, the distal end of the pressing inner catheter section 2100 being connected to the proximal end of the curved inner catheter section 2200. The diameter of the curved inner catheter section 2200 is greater than the diameter of the pressing inner catheter section 2100. The guidewire 2100b is inserted into the guide lumen 2100a of the inner catheter 2000, and the traction wire 2200b is connected to the curved inner catheter section 2200.

[0036] The statement "The inner catheter 2000 is movably positioned within the axial lumen of the outer catheter 1000" essentially means that the inner catheter 2000 can move axially and rotate circumferentially within the axial lumen of the outer catheter 1000 relative to the outer catheter 1000. The stent body D with valve C can be positioned between the inner catheter 2000 and the outer catheter 1000, or in the curved inner catheter section 2200 of the inner catheter 2000. In one embodiment, the outer catheter 1000 has an axially aligned compression outer catheter section 1100 and a curved outer catheter section 1200, the distal end of the compression outer catheter section 1100 may be connected to the proximal end of the curved outer catheter section 1200. In this case, the compression outer catheter section 1100 of the outer catheter 1000 can have a structure corresponding to and match the compression inner catheter section 2100 of the inner catheter 2000. The curved outer catheter section 1200 of the outer catheter 1000 can be structurally corresponding to and matched with the curved inner catheter section 2200 of the inner catheter 2000. The length of the curved outer catheter section 1200 can be adjusted based on the curvature control requirements. The stent body D with valve C can be positioned between the curved inner catheter section 2200 of the inner catheter 2000 and the curved outer catheter section 1200 of the outer catheter 1000.

[0037] Referring to Figure 1, the connection position between the traction wire 2200b and the curved inner catheter section 2200 is determined. When the traction wire 2200b is retracted, the curved inner catheter section 2200 is pulled at that position. That is, when a force F is applied, the traction wire 2200b bends the curved inner catheter section 2200. Since the diameter of the curved inner catheter section 2200 is larger than the diameter of the compression inner catheter section 2100, pulling the large-diameter curved inner catheter section 2200 via the traction wire 2200b generates a relatively large moment perpendicular to the cross-section of the curved inner catheter section 2200, resulting in a good bending control effect. In other words, by increasing the outer diameter of the curved inner catheter section 2200 and decreasing its elastic modulus, a large bending angle can be given to the inner catheter 2000.

[0038] To accommodate the variable diameter bending control of the inner catheter 2000, the curved outer catheter section 1200 can be designed with extended length to provide greater space, without limiting the present invention. Furthermore, the traction wire 2200b can be connected to any position on the curved inner catheter section 2200. For example, in one embodiment, the distal end of the traction wire 2200b may be connected to the distal end, middle section, or another position on the curved inner catheter section 2200. Those skilled in the art can adjust the connection position of the traction wire 2200b to the curved inner catheter section 2200 based on the bending control requirements of the curved inner catheter section 2200, without limiting the present invention.

[0039] The traction wire 2200b may be connected directly or indirectly to the curved inner catheter section 2200. For example, the traction wire 2200b may be connected to the curved inner catheter section 2200 by ligation, entanglement, welding, or the like. Alternatively, the curved inner catheter section 2200 may be provided with a traction fixing member 2210 for connecting the traction wire 2200b to the curved inner catheter section 2200. In this case, the position of the traction wire 2200b on the curved inner catheter section 2200 will be the same as the position of the traction fixing member 2210 on the curved inner catheter section 2200.

[0040] Connected to the curved inner catheter section 2200, the traction wire 2200b can be extended axially to its proximal end. For example, the traction wire 2200b extends axially to its proximal end through the gap between the inner catheter 2000 and the outer catheter 1000. Alternatively, the inner catheter 2000 may have a traction lumen 2200a, and the traction wire 2200b may be extended axially to its proximal end by inserting the traction wire 2200b into the traction lumen 2200a of the inner catheter 2000. Since the traction wire 2200b is located within the inner catheter 2000, manipulating the traction wire 2200b allows the delivery system to be bent distally without affecting the relative axial movement of the inner catheter 2000 and the outer catheter 1000, i.e., the advancement and retraction of the outer catheter 1000 relative to the inner catheter 2000. The advancement and retraction of the outer catheter 1000 can control the deployment and retrieval of the stent body D with valve C. Although not limited, the advancement and retraction of the external catheter 1000 can be controlled by a button.

[0041] Since the diameter of the curved inner catheter section 2200 is larger than the diameter of the compression inner catheter section 2100, the connection point between the compression inner catheter section 2100 and the curved inner catheter section 2200 can be a transitional section with a changing diameter or a stepped transitional section. For example, the proximal end of the curved inner catheter section 2200 has a variable diameter segment connected to the distal end of the compression inner catheter section 2100. The diameter of the variable diameter segment of the curved inner catheter section 2200 gradually decreases from the distal end to the proximal end, thereby forming a transitional connection between the curved inner catheter section 2200 and the compression inner catheter section 2100, which have different diameters. Furthermore, the traction lumen 2200a, which penetrates the curved inner catheter section 2200 and the compression inner catheter section 2100, changes in its radial distance from the central axis of the inner catheter 2000 in accordance with the change in the diameters of the curved inner catheter section 2200 and the compression inner catheter section 2100. Referring to Figure 1, along the direction of the tensile force F of the traction wire 2200b, the traction lumen 2200a and the traction wire 2200b within it have radial distances L2 and L1 in the curved inner catheter section 2200 and the pressing inner catheter section 2100, respectively, where L2 is smaller than L1.

[0042] The curved outer catheter section 1200 may be composed of layers of different materials. For example, the curved outer catheter section 1200 may have an outer polymer layer, an inner polymer layer, and a metal cutting reinforcement layer positioned between the outer and inner polymer layers. The outer polymer layer may be composed of a flexible material such as polyurethane or a polyamide polyether copolymer, and the inner polymer layer may be composed of a flexible material such as polytetrafluoroethylene, polyurethane, or a polyamide polyether copolymer. Since the curved outer catheter section 1200 is required to have properties such as bendability, high pressure resistance, and good hoop rigidity, the metal cutting reinforcement layer may be formed of a highly elastic NiTi alloy material. Those skilled in the art can manufacture curved outer catheter sections 1200 as needed without limiting the present invention.

[0043] Referring to Figures 4 to 6, in one embodiment, the reinforcing structure 1210 is provided on the outer surface of the curved outer catheter section 1200. The reinforcing structure 1210 may be provided in any suitable form. For example, the reinforcing structure 1210 can be reinforcing ribs provided on the outer surface of the curved outer catheter section 1200. The number of reinforcing ribs can be two or more. The reinforcing ribs can be distributed along the axial direction of the curved outer catheter section 1200. Referring to Figure 5, the reinforcing structure 1210 is provided as arc-shaped elements arranged around the curved outer catheter section 1200, with multiple reinforcing structures arranged in parallel. The arc-shaped elements may be arranged symmetrically on the opposite side of the curved outer catheter section 1200. This axial distribution of the reinforcing structure 1210 provides good compressive resistance and excellent bendability in a plane perpendicular to the reinforcing structure 1210.

[0044] Referring to Figure 6, the distal end of the curved outer catheter section 1200 is provided with a variable segment 1220 that includes a straight cylindrical configuration and a tapered cylindrical configuration. The variable segment 1220 is configured to change between the straight cylindrical configuration and the tapered cylindrical configuration. Therefore, the variable segment 1220 has a trumpet-shaped, i.e., tapered cylindrical configuration that serves as a guide when retrieving the stent body D, and may be restored to its original state, i.e., the straight cylindrical configuration, after retrieval is complete. The variable segment 1220 can be provided in various forms. For example, as shown in Figure 6, the variable segment 1220 is provided as a plurality of straight struts arranged circumferentially on the curved outer catheter section 1200. One end of the plurality of straight struts is connected to the distal end of the curved outer catheter section 1200, forming a fixed diameter. On the other hand, the other end of the plurality of straight struts is directed toward the distal end, forming a cantilever structure. As a result, when radial inward stress is applied during the retrieval of the stent body D, the straight strut deflects inward, and the variable segment 1220 takes on a tapered cylindrical configuration. Furthermore, when such stress is no longer applied, it returns to a straight cylindrical configuration.

[0045] The proximal end of the curved outer catheter section 1200 has a variable diameter segment connected to the distal end of the compression outer catheter section 1100. The diameter of the variable diameter segment of the curved outer catheter section 1200 gradually decreases from the distal end to the proximal end. The curved outer catheter section 1200 may coincide in length with the curved inner catheter section 2200. For example, the variable diameter segment at the proximal end of the curved inner catheter section 2200 may terminate at the variable diameter segment at the proximal end of the curved outer catheter section 1200.

[0046] The compression outer catheter section 1100 may be composed of layers of different materials. For example, the compression outer catheter section 1100 can be a composite catheter composed of an outer polymer layer, an inner polymer layer, an outer catheter braid layer, and a distal metal ring. The outer polymer layer may be composed of polyamide, polyamide polyether copolymer, or another material, and the inner polymer layer may be composed of polytetrafluoroethylene, high-density polyethylene, polyamide, polyamide polyether copolymer, or another material. The outer catheter braid layer is located between the outer polymer layer and the inner polymer layer and may be braided with metal reinforcing wire. To reinforce the structure of the compression outer catheter section 1100, the compression outer catheter section 1100 may further have reinforcing structures 1210, such as reinforcing ribs, symmetrically positioned on opposite sides along the axial direction. By symmetrically positioning the reinforcing ribs on opposite sides of the compression outer catheter section 1100, not only is good curvature in the plane perpendicular to the reinforcing ribs provided, but the desired compression resistance can also be provided.

[0047] In one embodiment, the distal end of the compression outer catheter section 1100 may be connected to the proximal end of the curved outer catheter section 1200 by heat fusion or the like. Furthermore, a connecting ring 1300 may be provided between the distal end of the compression outer catheter section 1100 and the proximal end of the curved outer catheter section 1200. The connecting ring 1300 is extrapolated to the connection point between the compression outer catheter section 1100 and the curved outer catheter section 1200 and to the portion adjacent to the connection point. The connecting ring 1300 is used to surround and reinforce the connection point between the distal end of the compression outer catheter section 1100 and the proximal end of the curved outer catheter section 1200.

[0048] To reinforce the structure of the compression outer catheter section 1100, an outer catheter reinforcing member 1110 can be provided on the compression outer catheter section 1100. The outer catheter reinforcing member 1110 may employ reinforcing ribs, of which there are two or more, and the reinforcing ribs are arranged along the axial direction of the compression outer catheter section 1100. The connecting ring 1300 can be manufactured using a metal material, and the distal end of the compression outer catheter section 1100 may be connected to the connecting ring 1300 by welding. Furthermore, the connecting ring 1300 at the distal end of the compression outer catheter section 1100 is welded to the outer catheter reinforcing member 1110, and a welded position 1110a is formed between the connecting ring 1300 and the outer catheter reinforcing member 1110. This allows the outer catheter reinforcing member 1110 to provide better support, ensuring stable discharge and retrieval of the stent body D, avoiding excessive stress on the pressing inner catheter section 2100 during retrieval of the stent body D, and preventing the end reinforcing ribs from falling off and causing a sudden decrease in compressive resistance.

[0049] The curved inner catheter section 2200 has a flexible backbone 2250 and a flexible protective layer. The flexible backbone 2250 is located within the flexible protective layer and functions as the backbone of the curved inner catheter section 2200, and the flexible protective layer covers and protects the backbone. The flexible backbone 2250 can be provided in various forms. Referring to Figure 7, in one embodiment, the flexible backbone 2250 has a backbone tube 2251, and the wall of the backbone tube 2251 has a curved auxiliary opening 2251a formed therein. The curved auxiliary opening 2251a is a linear opening and is located circumferentially on the backbone tube 2251. The curved auxiliary opening 2251a may be located in at least a portion of the circumferential direction of the backbone tube 2251. There are multiple curved auxiliary openings 2251a. Multiple curved auxiliary openings 2251a may be arranged along the axial direction of the backbone tube 2251 and may be arranged symmetrically on opposite sides of the backbone tube 2251. The curved auxiliary openings 2251a on one side may be offset along the axial direction relative to the curved auxiliary openings 2251a on the other side. Those skilled in the art can arrange the curved auxiliary openings 2251a as needed, without limiting the scope of this application.

[0050] In one embodiment, the flexible protective layer may have a flexible inner protective layer and a flexible outer protective layer. The flexible outer protective layer is provided on the outer surface of the backbone tube 2251, and the flexible inner protective layer is provided on the inner surface of the backbone tube 2251 and is arranged to enclose the backbone tube 2251. The flexible outer protective layer may be formed of a flexible polymer material such as polyurethane or polyamide polyether copolymer, and the flexible inner protective layer may be formed of a polymer such as polytetrafluoroethylene, high-density polyethylene, polyurethane, or polyamide polyether copolymer. The backbone tube 2251 may be formed of a metal material, in which case the backbone tube 2251 with a bending auxiliary opening 2251a can be manufactured by laser cutting.

[0051] Referring to Figure 7, in one embodiment, the flexible backbone 2250 has a plurality of rotatable elements 2252 arranged along the axial direction of the flexible backbone 2250. Adjacent rotatable elements 2252 are articulated with each other, and adjacent rotatable elements 2252 are rotatably connected to a fixed axis, with multiple rotation axes between the plurality of rotatable elements 2252 being parallel to each other. The rotatable elements 2252 are, for example, snakebone-like elements, and are riveted together to form the backbone tube 2251. The riveted snakebone-like structure exhibits excellent adaptability, uniformly distributing the force from the traction wire 2200b throughout the backbone tube 2251 and significantly reducing the flexural modulus of the backbone tube 2251. The riveted snakebone-like structure exhibits excellent tensile performance. The flexible protective layer can be formed from a flexible polymer material such as polyurethane or polyamide polyether copolymer and can be placed directly on the outer surface of the flexible backbone 2250.

[0052] Referring to Figure 9, in one embodiment, the pressing inner catheter section 2100 includes an inner catheter inner layer 2110, an inner catheter outer layer 2120, and an inner catheter braided layer 2130 positioned between the inner catheter inner layer 2110 and the inner catheter outer layer 2120. At least one of the guide lumen 2100a and the traction lumen 2200a is formed inside the inner catheter inner layer 2110. The inner catheter outer layer 2120 can be formed of a matrix material such as polyamide or polyamide polyether copolymer, and the inner catheter inner layer 2110 can be formed of a self-lubricating polytetrafluoroethylene material, thereby providing self-lubrication to the traction lumen 2200a formed by the inner catheter inner layer 2110. An inner catheter reinforcing element 2140 is provided within the inner catheter inner layer 2110, located between the guide lumen 2100a and the traction lumen 2200a.

[0053] The traction lumen 2200a is provided with a bend-resistant support tube 2200c. The bend-resistant support tube 2200c exhibits bending resistance, and under the tensile force of the traction wire 2200b, the bend-resistant support tube 2200c allows the pressing inner catheter section 2100, including the traction lumen 2200a, to withstand greater stress and minimize deformation. As a non-limiting example, the bend-resistant support tube 2200c can be implemented as a high-density compression spring tube, etc. The high-density compression spring tube can be placed between the inner catheter inner layer 2110 and the inner catheter braided layer 2130, allowing the inner catheter braided layer 2130 to increase hoop restraint force. When tension is applied to the traction wire 2200b, the inner catheter 2000 tends to contract due to the force acting along its axial direction. However, because the high-density compression spring tube provides sufficient support, the inner catheter 2000 deforms only slightly as a whole. When the inner catheter 2000 is bent, a force perpendicular to its axis is generated. However, the restraint of the inner catheter braid layer 2130 provides greater hoop rigidity, thus preventing the inner catheter 2000 from deforming in the circumferential direction.

[0054] Referring to Figure 10, an internal catheter connecting segment 2300 is provided at the proximal end of the internal compression catheter section 2100, and correspondingly, an external catheter connecting portion 1120 can be provided on the external compression catheter section 1100, which is externally fitted onto the internal catheter connecting segment 2300. The internal catheter connecting segment 2300 is provided with a wire outlet 2310 that communicates with the traction lumen 2200a, and the proximal end of the traction wire 2200b is drawn out from this outlet. The distal end of the internal catheter connecting segment 2300 is connected to the internal compression catheter section 2100, and the proximal end of the internal catheter connecting segment 2300 is configured to be connected to a gripping member 3000 such as a handle. The internal catheter connecting segment 2300 can be provided with a screw 3200 at its proximal end, and the internal catheter connecting segment can be connected to the gripping member 3000 by screw engagement. The gripping member 3000 may be provided with a rotatable rotation control member 3100 to control the tightening or loosening of the traction wire 2200b. The internal catheter connecting segment 2300 is a reinforcing tube made of a metal material with structural reinforcing properties and may consist of a first connecting segment 2300a and a second connecting segment 2300b. The proximal end of the first connecting segment 2300a is connected to the gripping member 3000, and the distal end of the first connecting segment 2300a is connected to the proximal end of the second connecting segment 2300b. The distal end of the second connecting segment 2300b is connected to the compressed internal catheter section 2100 by integral fusion. Such integral fusion ensures smooth passage for overall bending control. In this case, the high-density compression spring tube extends from the distal end to the wire exit 2310 and does not obstruct the axial passage of the traction wire 2200b.

[0055] Referring to Figures 11 to 21, the traction fixing member 2210 is positioned at the distal end of the curved inner catheter section 2200. Referring to Figure 13, the traction fixing member 2210 has a first internal bore 2210a that communicates with the guide lumen 2100a, thereby allowing the guidewire 2100b to protrude from the distal end of the traction fixing member 2210. The traction fixing member 2210 is provided with a first wire attachment member 2210b, and the traction wire 2200b is connected to the first wire attachment member 2210b and further connected to the distal end of the curved inner catheter section 2200.

[0056] The curved inner catheter section 2200 is provided with a stent fixation member 2220 at its proximal end, which connects the curved inner catheter section 2200 to the distal end of the pressing inner catheter section 2100. Referring to Figure 14, the stent fixation member 2220 is provided with a second internal bore 2220a that communicates with the guide lumen 2100a. The second internal bore 2220a allows the guidewire 2100b to protrude from the proximal end of the stent fixation member 2220. The stent fixation member 2220 has a stent fixation element 2220c for fixing the stent body D with valve C. Specifically, the proximal portion of the stent body D with valve C is positioned on the curved inner catheter section 2200 by the stent fixation member 2220 so that the stent body D is pressed against the curved inner catheter section 2200. The stent fixation member 2220 has a lateral traction wire hole 2220b that communicates with the traction lumen 2200a. The proximal end of the traction wire 2200b is inserted into the lateral traction wire hole 2220b and extends proximal, eventually being drawn out from the wire exit point 2310 of the internal catheter connecting segment 2300.

[0057] Referring to Figures 15 and 16, the traction fixing member 2210, the flexible backbone 2250, the stent fixing member 2220, and the fusion connecting claw 2260 are welded to the fixing assembly. The traction wire 2200b can be connected to the traction fixing member 2210 in various ways. For example, two traction wires 2200b can be passed proximal to the flexible backbone 2250, and then through the lateral traction wire hole 2220b of the stent fixing member 2220 to suspend the traction wire 2200b from the traction fixing member 2210. Next, the fusion connecting claw 2260 is heat-bonded and wrapped around the distal end of the pressing inner catheter section 2100. In this configuration, the lateral traction wire hole 2220b of the stent fixing member 2220 communicates with the guide lumen 2200a of the inner catheter 2000, forming a complete traction lumen 2200a.

[0058] Referring to Figures 17 to 21, when a tensile force directed towards the proximal end is applied to the traction wire 2200b, the curved inner catheter section 2200 and the curved outer catheter section 1200 may bend to some extent, depending on their respective flexural moduli and lengths. To ensure the performance of valve C, the lengths of the curved inner catheter section 2200 and the curved outer catheter section 1200 may be shorter than the distance between the traction fixing member 2210 and valve C.

[0059] After the stent body D with valve C is loaded into the inner catheter 2000 and outer catheter 1000 of the delivery system, the inner catheter 2000 and outer catheter 1000 can be advanced through the aortic arch A. If resistance is encountered, both the curved inner catheter section 2200 and the curved outer catheter section 1200 are deflected by a small angle before advancement. After deflection, the distal ends of both the curved inner catheter section 2200 and the curved outer catheter section 1200, as well as the traction wire 2200b, move away from the vessel wall, thereby facilitating advancement. If the inner catheter 2000 and outer catheter 1000 are not steerable, after passing through the aortic arch A and the annulus, they become straight as a whole, oriented at a relatively large angle to the annular plane B, and if the stent body D is released at this point, the stent body D may detach or tilt. In contrast, according to the present invention, the deflection adjustment of both the inner catheter 2000 and the outer catheter 1000 is performed when traversing the annular portion. The stent body D and guidewire 2100b bend together with the inner catheter 2000 and outer catheter 1000, so that the inner catheter 2000 and outer catheter 1000 are perpendicular to the annular plane B. The angle at which the inner catheter 2000 and outer catheter 1000 bend may vary depending on the actual anatomical structure of the valve arch, and this invention is not particularly limited in this respect.

[0060] Controlled deflection adjustment of both the inner catheter 2000 and the outer catheter 1000 allows for control of the curvature of the stent body D. By adjusting the curvature angle, coaxial deployment suitable for over 98% of the patient's anatomical structures is possible. During the procedure, the outer catheter 1000 can be retracted by operating a push button on the handle, and the inner catheter 2000, due to its controlled bending mechanism, maintains a stable bend throughout the entire release process, while the stent body D remains perpendicular to the annular plane B. This allows for stable and precise release of the stent body D to the target site. Furthermore, the stent body D is passively steered at the posterior end and is released from the steering action and fully released after the stent body D is stably anchored. The anchoring of the stent body D is not affected at all.

[0061] Referring to Figures 22 to 29, the curved internal catheter section 2200 may have a first internal catheter segment 2230 and a second internal catheter segment 2240 aligned axially. As a non-limiting alternative to this two-segment structure, the curved internal catheter section 2200 may also include three or more segments. A traction fixing member 2210 is provided at the distal end of the second internal catheter segment 2240 and comprises a first internal bore 2210a. The first internal bore 2210a communicates with a guide lumen 2100a and is configured so that a guidewire 2100b can protrude from the distal end of the traction fixing member 2210. The traction fixing member 2210 may have a first wire attachment member 2210b, and the traction wire 2200b is connected to the first wire attachment member 2210b and further connected to the distal end of the curved internal catheter section 2200.

[0062] The distal end of the first internal catheter segment 2230 may be connected to the proximal end of the second internal catheter segment 2240 by a stent fixing member 2220 having a second internal bore 2220a. The second internal bore 2220a communicates with the traction lumen 2100a and is configured so that a guidewire 2100b can protrude from the proximal end of the stent fixing member 2220. The stent fixing member 2220 may include a stent fixing element 2220c for fixing a stent body D with a valve C. Specifically, the proximal portion of the stent body D with valve C is sleeve-like externally fitted onto the curved internal catheter section 2200 by the stent fixing member 2220, and the stent body D is crimped onto the curved internal catheter section 2200. The stent fixing member 2220 may include a lateral traction wire hole 2220b communicating with the traction lumen 2200a. The proximal end of the traction wire 2200b is inserted into the lateral traction wire hole 2220b and extends proximal, eventually being drawn out from the wire exit point 2310 of the internal catheter connecting segment 2300.

[0063] Referring to Figures 24 and 25, the traction fixing member 2210, the flexible backbone 2250 in the second internal catheter segment 2240, the stent fixing member 2220, the flexible backbone 2250 in the first internal catheter segment 2230, and the fusion connecting claw 2260 are welded to the fixing assembly. The traction wire 2200b can be connected to the traction fixing member 2210 in various ways. For example, two traction wires 2200b may be passed sequentially proximal through the flexible backbone 2250 in the second internal catheter segment 2240, the lateral traction wire hole 2220b of the stent fixing member 2220, and the flexible backbone 2250 of the first internal catheter segment 2230, thereby suspending the traction wire 2200b from the traction fixing member 2210. The fusion connecting claw 2260 is heat-bonded and wrapped around the distal end of the pressing internal catheter section 2100. With this configuration, the lateral traction wire hole 2220b of the stent fixing member 2220 communicates with the guide lumen 2200a of the inner catheter 2000, forming a complete traction lumen 2200a.

[0064] Referring to Figures 26 to 29, when a tensile force directed towards the proximal end is applied to the traction wire 2200b, the curved inner catheter section 2200 and the curved outer catheter section 1200 may bend to some extent, depending on their respective flexural moduli and lengths. To ensure the performance of valve C, the lengths of the curved inner catheter section 2200 and the curved outer catheter section 1200 can be shorter than the distance between the traction fixing member 2210 and valve C. Since the curved inner catheter section 2200 is a two-segment structure including a first inner catheter segment 2230 and a second inner catheter segment 2240 along the axial direction, it can be bent at a large angle when a certain force is applied to it.

[0065] After the stent body D with valve C is loaded into the inner catheter 2000 and outer catheter 1000 of the delivery system, the inner catheter 2000 and outer catheter 1000 can be advanced through the aortic arch A. If resistance is encountered, a small angle of deflection is applied to both the curved inner catheter section 2200 and the curved outer catheter section 1200 before advancement. After deflection, the distal ends of both the curved inner catheter section 2200 and the curved outer catheter section 1200, as well as the traction wire 2200b, move away from the vessel wall, thereby facilitating advancement. After passing the annulus, the deflection adjustment of both the inner catheter 2000 and the outer catheter 1000 is performed. The stent body D and guide wire 2100b bend together with the inner catheter 2000 and outer catheter 1000, so that the inner catheter 2000 and outer catheter 1000 are perpendicular to the annular plane B. The angles at which the inner catheter 2000 and the outer catheter 1000 bend may vary depending on the actual anatomical structure of the arch, and this invention is not particularly limited in this respect.

[0066] The two-segment structure of the curved inner catheter section 2200, which includes a first inner catheter segment 2230 and a second inner catheter segment 2240 along the axial direction, is a labor-saving design suitable for 90% of patients and a wider range of applications. During the procedure, the outer catheter 1000 can be retracted by operating a push button on the handle, and the inner catheter 2000 maintains a stable bent state throughout the entire release process due to its controlled bending mechanism, and the stent body D maintains a state perpendicular to the annular plane B. This efficiently ensures that the stent body D is released stably and accurately to the target site. Furthermore, the stent body D is passively steered at the posterior end and is released from the steering action and completely released after the stent body D is stably anchored. Therefore, the anchoring of the stent body D is not affected at all.

[0067] Referring to Figures 30 to 38, the stent fixing member 2220 is provided at the distal end of the curved inner catheter section 2200, and the proximal end of the curved inner catheter section 2200 may be directly connected to the compression inner catheter section 2100. The stent fixing member 2220 has a second internal bore 2220a, which communicates with the guiding lumen 2100a, and is configured so that the guidewire 2100b can protrude from the distal end of the stent fixing member 2220. The stent fixing member 2220 may have a stent fixing element 2220c for fixing a stent body D with a valve C, and the stent body D with valve C does not cover the curved inner catheter section 2200. The stent fixing member 2220 may further have a second wire attachment member 2220d, and the traction wire 2200b may be connected to the second wire attachment member 2220d. With this configuration, the stent fixing member 2220 has both the function of fixing the stent body D at the distal end of the curved inner catheter section 2200 and the function of connecting the traction wire 2200b.

[0068] Referring to Figures 33 and 34, the stent fixation member 2220, the flexible backbone 2250, and the fusion connecting claws 2260 are welded to the fixation assembly. The traction wires 2200b can be connected to the stent fixation member 2220 in various ways. For example, the traction wires 2200b can be suspended from the traction fixation member 2210 by passing two traction wires 2200b proximal to the flexible backbone 2250 and drawing them into the traction lumen 2200a of the internal catheter 2000. The fusion connecting claws 2260 are heat-bonded and wrapped around the distal end of the pressing internal catheter section 2100.

[0069] Referring to Figures 35 to 38, when a tensile force directed towards the proximal end is applied to the traction wire 2200b, the curved inner catheter section 2200 and the curved outer catheter section 1200 may bend to some extent, depending on their respective flexural moduli and lengths. To ensure the performance of valve C, the lengths of the curved inner catheter section 2200 and the curved outer catheter section 1200 may be shorter than the distance between the traction fixing member 2210 and valve C.

[0070] In these embodiments, since the stent body D is fixed to the stent fixing member 2220 at the distal end described above, the curved inner catheter section 2200 and the curved outer catheter section 1200 cannot be steered to bend the stent body D. Therefore, they have a relatively long straight length. This configuration is suitable for use in patients with long ascending aortas and can achieve coaxial release in more than 80% of target patients. After loading the stent body D with valve C into the inner catheter 2000 and outer catheter 1000 of the delivery system, the inner catheter 2000 and outer catheter 1000 can be advanced through the aortic arch A. If resistance is encountered, both the curved inner catheter section 2200 and the curved outer catheter section 1200 are given a small angle of deflection before being advanced. After deflection, both distal ends of the curved inner catheter section 2200 and the curved outer catheter section 1200, as well as the traction wire 2200b, move away from the vessel wall, thereby facilitating advancement, and the curved inner catheter section 2200 and the curved outer catheter section 1200 become perpendicular to the annular plane B.

[0071] During the procedure, the outer catheter 1000 can be retracted by operating a push button on the handle, and the inner catheter 2000 maintains a stable bend throughout the entire release process due to its controlled bending mechanism, while the stent body D remains perpendicular to the annular plane B. This allows the stent body D to be released stably and accurately to the target site. Furthermore, the stent body D is passively steered at its posterior end and is released from the steering action and completely released after the stent body D is stably anchored. Therefore, the anchoring of the stent body D is not affected at all.

[0072] The various technical features of the embodiments described above can be combined in any way. For the sake of brevity, not all such combinations have been described above, but any combination therein is considered to be within the scope of this specification, as long as there is no contradiction between the technical features.

[0073] The above describes only some embodiments of the present application. Although these embodiments are described to some extent in specificity and detail, they do not limit the scope of the present application in any sense. It goes without saying that those skilled in the art can make various changes and modifications without departing from the concepts of the present application. Accordingly, all such variations and modifications are included in the scope of the present application as defined in the appended claims. [Explanation of Symbols]

[0074] A: Aortic arch B: Annular plane C: Artificial valve D: Stent body E: Support point F: Anchor point G: Pull-out direction 1000: External catheter 2000: Internal catheter 3000: Gripping member 1100: Compression of the outer catheter section 1200: Curved lateral catheter section 1300: Connecting ring 1110: External catheter reinforcement member 1110a: Welding position 1120: External catheter connection 1210: Reinforcement structure 1220: Variable segment 2100a: Guidance lumen 2100b: Guidewire 2200a: Traction lumen 2200b: Towing wire 2200c: Bending-resistant support tube 2100: Compression of the internal catheter section 2200: Curved medial catheter section 2300: Inner catheter linkage segment 2300a: First consolidated segment 2300b: Second consolidated segment 2110: Inner layer of the catheter 2120: Inner catheter outer layer 2130: Inner catheter braided layer 2140: Internal catheter reinforcement element 2210: Towing and fixing member 2220: Stent fixing component 2230: First internal catheter segment 2240: Second internal catheter segment 2250: Flexible backbone 2260: Fusion Connection Claw 2310: Wire outlet 2210a: First inner bore 2210b: First wire attachment member 2220a: Second inner bore 2220b: Lateral traction wire hole 2220c: Stent fixing element 2220d: Second wire attachment member 2251: Backbone tube 2251a: Curved auxiliary opening 2252: Rotatable element 3100: Rotation control member 3200: Screw

Claims

1. An external catheter having an axial lumen, An internal catheter having a guide lumen, wherein the internal catheter is movably disposed within the axial lumen of the external catheter, and the internal catheter has a pressing internal catheter section and a curved internal catheter section along the axial direction, the distal end of the pressing internal catheter section is connected to the proximal end of the curved internal catheter section, and the diameter of the curved internal catheter section is greater than the diameter of the pressing internal catheter section, A guide wire inserted into the guide lumen of the internal catheter, A traction wire connected to the curved inner catheter section, A delivery system equipped with the following features.

2. The delivery system according to claim 1, wherein the distal end of the traction wire is connected to the distal end of the curved inner catheter section.

3. The delivery system according to claim 1, wherein the curved inner catheter section is provided with a traction fixing member, and the traction wire is connected to the curved inner catheter section via the traction fixing member.

4. The delivery system according to claim 3, wherein the traction fixing member has a first internal bore that communicates with the guide lumen.

5. The delivery system according to claim 3, wherein the towing fixing member is provided with a first wire attachment member, and the towing wire is connected to the first wire attachment member.

6. The delivery system according to claim 1, wherein the internal catheter has a traction lumen, and the traction wire is inserted into the traction lumen of the internal catheter.

7. A flexible support tube is provided inside the traction lumen. and / or, The delivery system according to claim 6, wherein an internal catheter connecting segment is provided at the proximal end of the pressing internal catheter section, a wire exit port is provided at the internal catheter connecting segment, the wire exit port is in communication with the traction lumen, and the proximal end of the traction wire is drawn out from the wire exit port.

8. The delivery system according to claim 1, wherein the proximal end of the curved inner catheter section has a variable diameter segment connected to the distal end of the pressing inner catheter section, and the diameter of the variable diameter segment of the curved inner catheter section gradually decreases from the distal end to the proximal end.

9. The delivery system according to claim 1, wherein a stent fixing member is provided in the curved inner catheter section.

10. The stent fixing member is provided at the proximal end of the curved inner catheter section, and the curved inner catheter section is connected to the distal end of the pressing inner catheter section via the stent fixing member. Or, The delivery system according to claim 9, wherein the stent fixing member is provided at the distal end of the curved inner catheter section.

11. The curved inner catheter section has a first inner catheter segment and a second inner catheter segment along the axial direction, and the distal end of the first inner catheter segment is connected to the proximal end of the second inner catheter segment via the stent fixing member. and / or, The stent fixing member has a second internal bore that communicates with the guide lumen, and / or, The delivery system according to claim 9, wherein the stent fixing member has a stent fixing element.

12. The delivery system according to claim 1, wherein the curved inner catheter section has a flexible backbone and a flexible protective layer, and the flexible backbone is disposed within the flexible protective layer.

13. The flexible backbone has a backbone tube, and the wall of the backbone tube is provided with at least one bending auxiliary opening. (i) The curved auxiliary opening is a linear opening, the curved auxiliary opening is arranged in the circumferential direction of the backbone tube, there are multiple curved auxiliary openings, and the multiple curved auxiliary openings are distributed along the axial direction of the backbone tube, and / or, (ii) The delivery system according to claim 12, wherein the flexible protective layer comprises a flexible inner protective layer and a flexible outer protective layer, the flexible outer protective layer being provided on the outer surface of the backbone tube and the flexible inner protective layer being provided on the inner surface of the backbone tube.

14. The delivery system according to claim 12, wherein the flexible backbone includes a plurality of rotatable elements distributed along the axial direction of the flexible backbone, and adjacent rotatable elements are articulated to each other.

15. The delivery system according to claim 14, wherein adjacent rotatable elements are rotatably connected to a fixed axis, and the multiple axes of rotation of the multiple rotatable elements are parallel.

16. The delivery system according to claim 6, wherein the pressing inner catheter section has an inner catheter inner layer and an inner catheter outer layer, an inner catheter braid layer is disposed between the inner catheter inner layer and the inner catheter outer layer, and at least one of the guiding lumen and the traction lumen is formed inside the inner catheter inner layer.

17. The delivery system according to claim 16, wherein at least one internal catheter reinforcing element is disposed inside the inner layer of the internal catheter and is located between the guiding lumen and the traction lumen.

18. The delivery system according to claim 1, wherein the outer catheter has a pressing outer catheter section and a curved outer catheter section along the axial direction, and the distal end of the pressing outer catheter section is connected to the proximal end of the curved outer catheter section.

19. The delivery system according to claim 18, wherein the distal end of the curved outer catheter section has a variable segment including a straight cylindrical configuration and a tapered cylindrical configuration, the variable segment being configured to change between the straight cylindrical configuration and the tapered cylindrical configuration.

20. The delivery system according to claim 18, wherein the proximal end of the curved outer catheter section has a variable diameter segment connected to the distal end of the pressing outer catheter section, and the diameter of the variable diameter segment of the curved outer catheter section gradually decreases from the distal end to the proximal end.

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