CN112842645A

CN112842645A - Delivery guide wire and treatment device

Info

Publication number: CN112842645A
Application number: CN201911183783.0A
Authority: CN
Inventors: 龙平; 候娟; �田�浩
Original assignee: Microport Neurotech Shanghai Co Ltd
Current assignee: Microport Neurotech Shanghai Co Ltd
Priority date: 2019-11-27
Filing date: 2019-11-27
Publication date: 2021-05-28

Abstract

The invention relates to a conveying guide wire and a treatment device comprising the conveying guide wire, wherein the conveying guide wire comprises a mandrel and a driving component arranged on the mandrel, and comprises the mandrel and the driving component arranged on the mandrel, and the driving component comprises an inner layer piece and an outer layer piece, wherein the inner layer piece is made of a metal material and is fixedly sleeved on the mandrel; the outer layer piece is made of high polymer materials and is fixedly sleeved on the inner layer piece. Establish through fixed cover the epaxial inlayer piece of dabber indirectly strengthens outer layer spare with cohesion between the dabber makes outer layer spare is difficult to take place phenomenons such as not hard up, fold, aversion, improves and carries security and reliability that the seal wire used.

Description

Delivery guide wire and treatment device

Technical Field

The invention relates to the technical field of medical instruments, in particular to a delivery guide wire and a treatment device.

Background

Intracranial aneurysms are usually abnormal bulges on the wall of an intracranial artery, and are the first causes of subarachnoid hemorrhage. In cerebrovascular diseases, the incidence of intracranial aneurysm is second to cerebral thrombosis and hypertensive cerebral hemorrhage, and the intracranial aneurysm has great harm.

In the prior art, there are three main methods for treating intracranial aneurysms: (1) the surgical clamping method adopts a metal clamp to clamp the neck of the aneurysm to block intracranial aneurysm and cerebral circulation blood flow, and prevents the rupture and bleeding of the aneurysm while recovering normal blood supply of the parent artery. (2) The intratumoral embolization method adopts embolization materials to fill the aneurysm, so that thrombus is formed in the body of the aneurysm, and the rupture hemorrhage caused by further expansion of the body of the aneurysm is avoided. (3) The intravascular stent method is to implant a stent into a blood vessel to interfere the blood flow entering an aneurysm from a parent artery, so that the blood in the aneurysm is blocked and deposited, thereby forming aneurysm thrombus and further promoting the closure of the aneurysm body to prevent the rupture of the aneurysm body. Since aneurysms are generally longer than the periphery of the cerebral arterial loop, there are many important blood vessels, nerves and brain tissue around the cerebral arterial loop. When the surgical clamping method is used for treating the aneurysm, the medical requirements of doctors are extremely high, and the death rate of patients who treat the aneurysm by the surgical clamping method is still as high as 50 percent. When large or local large complicated aneurysms are treated by intratumoral embolization, the recurrence rate of patients is high. Currently, the most widely used treatment for intracranial aneurysms is endovascular stenting.

When intracranial aneurysm is treated by using an intravascular stent method, the stent is delivered into a blood vessel through a delivery guide wire. The delivery guide wire comprises a mandrel and a membrane structure arranged on the mandrel, the stent is loaded on the membrane structure, and under the action of friction force between the membrane structure and the stent, the stent moves synchronously along with the delivery guide wire. In the prior art, the film structure is directly adhered to the mandrel. When the film structure and the mandrel are connected by adopting a sticking method, the problem of poor bonding strength of the film structure and the mandrel exists due to small contact area, so that the film structure is easy to loosen, fold or shift in the process of conveying the bracket, and the condition of bracket unloading is further caused.

Disclosure of Invention

The invention aims to provide a conveying guide wire and a medical device, wherein the conveying guide wire has good flexibility and can effectively avoid the phenomenon of stent unloading caused by the looseness or displacement of an outer layer part in the process of conveying a stent.

In order to achieve the purpose, the invention provides a conveying guide wire, which comprises a mandrel and a driving component arranged on the mandrel, wherein the driving component comprises an inner layer piece and an outer layer piece,

the inner layer piece is made of a metal material and is fixedly sleeved on the mandrel;

the outer layer piece is made of high polymer materials and is fixedly sleeved on the inner layer piece.

Optionally, the inner ply has a void structure and the outer ply partially or completely fills the void structure.

Optionally, the outer skin is connected to the mandrel at least partially through the void structure.

Optionally, the outer surface of the inner layer member is provided with a recess, and the recess constitutes the void structure.

Optionally, the inner layer member includes a plurality of coils, the plurality of coils are sequentially arranged along the axial direction of the mandrel, and the void structure is formed between two adjacent coils.

Optionally, the inner layer member is a helical structure formed by a wire helically wound around the axis of the mandrel, and the void structure is formed between two adjacent turns of the wire.

Optionally, the inner layer member is a tube net structure woven by silk threads, and the mesh holes of the tube net structure form the gap structure.

Optionally, the wire has a diameter of less than or equal to 0.001 inches.

Optionally, the number of braid intersections per inch of length of the inner layer member is 15-50.

Optionally, the inner layer is at least one tubular structure, and the outer layer partially or completely covers the inner layer.

Optionally, a void structure is provided in the tubular structure, the outer layer partially or completely filling the void structure;

or the inner layer piece is at least two tubular structures, a gap structure is formed between the adjacent tubular structures, and the outer layer piece partially or completely fills the gap structure.

Alternatively, the inner layer member is made of a metal material having developability.

Optionally, the metallic material is selected from one or more of platinum, gold, tungsten, platinum-gold alloy, platinum-tungsten alloy, platinum-iridium alloy, and platinum-nickel alloy.

Optionally, the inner layer is welded to the mandrel, or the inner layer is glued to the mandrel.

Optionally, the material of the outer layer member includes any one or more of block polyether amide resin, thermoplastic polyurethane elastomer, silicone, nylon and acrylic polymer.

Optionally, the outer layer member wraps around the inner layer member and extends to connect with the mandrel.

Optionally, the outer layer is formed on the inner layer by hot pressing and/or dip coating, or the inner layer and the outer layer are bonded.

Optionally, the inner layer is integrally formed with the mandrel.

Optionally, the mandrel is provided with at least two driving members, and the at least two driving members are arranged at intervals along the axial direction of the mandrel.

To achieve the above object, the present invention further provides a treatment device comprising a delivery tube, a medical implant and a delivery guidewire as described in any of the previous items, the delivery tube having an axially through lumen for receiving the medical implant, and a wall of the lumen compressing the medical implant to cause the medical implant to be compressed; the compressed medical implant is sleeved on the driving component.

Optionally, the lumen has a radial dimension in a range of 0.017 inches to 0.029 inches.

Compared with the prior art, the conveying guide wire and the medical device have the following advantages:

the delivery guide wire comprises a mandrel and a driving component arranged on the mandrel, wherein the driving component comprises an inner layer piece and an outer layer piece, the inner layer piece is made of a metal material and is fixedly sleeved on the mandrel; the outer layer piece is made of high polymer materials and is fixedly sleeved on the inner layer piece. Because the inner layer piece is fixed (such as welded) on the mandrel, and the inner layer piece and the mandrel are both made of metal materials, the bonding strength is very high, and the inner layer piece and the mandrel cannot be displaced. The outer layer piece and the inner layer piece made of high polymer materials are fixedly connected through a specific structure, for example, a gap structure is arranged on the inner layer piece, and the gap structure is partially or completely filled in the outer layer piece, so that the inner layer piece and the outer layer piece are mutually embedded and matched; if the outer layer piece is used for coating the inner layer piece and further extends to be connected with the mandrel, the outer layer piece, the inner layer piece and the mandrel are in tight fit. The outer layer piece is arranged on the mandrel through the inner layer piece, and the inner layer piece and the outer layer piece have larger contact area, so that the connection strength is further improved. The connection mode in the prior art is changed by the above modes, so that the whole driving component can be firmly fixed on the mandrel, the phenomena of looseness, folds and displacement of the driving component in the process of conveying the bracket are avoided, and the reliability of the conveying guide wire in the process of conveying the medical implant is improved.

Drawings

FIG. 1 is a schematic view of a prior art treatment apparatus;

FIG. 2 is a schematic illustration of a delivery guidewire according to an embodiment of the present invention;

FIG. 3 is a partial cross-sectional view of a delivery guidewire according to one embodiment of the present invention showing multiple coils disposed in close proximity;

FIG. 4 is an enlarged schematic view at A of the delivery guidewire of FIG. 3;

FIG. 5 is a schematic structural view of a pushwire provided in accordance with an embodiment of the present invention, showing only a portion of the core shaft and an inner member disposed over the portion of the core shaft;

FIG. 6 is a schematic representation of a delivery guidewire according to another embodiment of the present invention;

FIG. 7 is an enlarged schematic view at B of the delivery guidewire of FIG. 6;

FIG. 8 is a schematic representation of a delivery guidewire provided in accordance with yet another embodiment of the present invention;

fig. 9 is an enlarged schematic view at C of the delivery guidewire shown in fig. 8.

FIG. 10 is a schematic structural view of a delivery guidewire provided in accordance with yet another embodiment of the invention;

in the figure:

10, 100-delivery guide wire;

11, 110-mandrel;

12-a structure of a membrane, wherein,

120-a take-along member;

121-inner layer, 122-outer layer, 123-void structure;

130-a first development;

140-a second development;

150-a reducing spring;

20-a scaffold;

30-conveying pipe.

Detailed Description

To further clarify the objects, advantages and features of the present invention, a more particular description of the invention will be rendered by reference to the appended drawings. It is to be noted that the drawings are in a very simplified form and are not to precise scale, which is merely for the purpose of facilitating and distinctly claiming the embodiments of the present invention.

As used in this specification, the singular forms "a", "an" and "the" include plural referents, and the plural forms "a plurality" includes two or more referents unless the content clearly dictates otherwise. As used in this specification, the term "or" is generally employed in its sense including "and/or" unless the content clearly dictates otherwise, and the terms "mounted," "connected," and "connected" are to be construed broadly, e.g., as meaning either fixedly connected, detachably connected, or integrally connected. Either mechanically or electrically. Either directly or indirectly through intervening media, either internally or in any other relationship. The specific meanings of the above terms in the present invention can be understood by those skilled in the art according to specific situations. The same or similar reference numbers in the drawings identify the same or similar elements.

As used herein, the terms "proximal" and "distal" refer to the relative orientation, relative position, and orientation of elements or actions with respect to one another from the perspective of an operator using the medical device, although "proximal" and "distal" are not intended to be limiting, but generally refers to the end of the medical device that is closer to the operator during normal operation, and generally refers to the end that is first introduced into the patient.

Fig. 1 shows a schematic structural view of a treatment apparatus in the prior art for delivering a medical stent to a predetermined position in a patient. As shown in fig. 1, the therapeutic device includes a delivery guide wire 10, a stent 20 and a delivery tube 30, the delivery guide wire 10 includes a core shaft 11 and a membrane structure 12 disposed on the core shaft 11, the delivery tube 30 has an inner cavity running through axially, the inner cavity is used for accommodating the stent 20, and the wall of the inner cavity presses the stent 20, so that the stent 20 is compressed, and the compressed stent 20 is sleeved on the membrane structure 12. In order to smoothly push the delivery wire in the delivery tube 30, the existing delivery wire 10 has a smooth outer surface, and the film structure 12 is disposed on the core shaft 11 of the delivery wire 10 to increase the first friction between the delivery wire 10 and the stent 30, and generally, the film structure 12 is made of a polymer material with a relatively high friction coefficient and is connected to the core shaft 11 made of a metal material by an adhesive method.

In the treatment device, the delivery tube 30, the stent 20 and the delivery guidewire 10 are in an interference state, that is, the delivery tube 10 exerts a radial force on the stent 20, and the stent 20 exerts a radial force on the delivery guidewire 10 (specifically, the membrane structure 12). When the operator pushes the pushwire 10 to axially move the pushwire 10 in the delivery tube 30, a first friction force is generated between the pushwire 10 and the inner surface of the stent 20, and the stent 20 can move synchronously with the pushwire 10 under the action of the friction force. Meanwhile, a second friction force is generated between the outer surface of the stent 20 and the inner wall of the delivery tube 30, since the diameter of the mandrel 11 is very small, the bonding area between the membrane structure 12 and the mandrel 11 is also very small, so that the bonding force between the membrane structure 12 and the mandrel 11 is relatively small, and the mandrel 11 and the membrane structure 12 are made of different materials, so that the connection strength is relatively low, and when the second friction force is too large, the membrane structure 12 is easily loosened, wrinkled or even displaced, so that the stent 20 is unloaded.

In view of the above problem, an object of the present embodiment is to provide a delivery guide wire for delivering a medical implant to a predetermined position in a patient, which can effectively reduce the occurrence probability of unloading the medical implant, and improve the safety and reliability of the delivery guide wire. The medical implant is, for example, a self-expanding stent (i.e., a self-expanding stent), which may be, in particular, a braided stent or a cut stent. In other embodiments, the medical implant may also be a medical embolic coil, a vascular occlusion device, or the like, without limiting the invention. Hereinafter, for the convenience of description, the medical implant is described as a self-expandable stent, and for the sake of simplicity, the self-expandable stent is uniformly referred to as a "stent".

Referring to fig. 2 to 4, the pushwire 100 provided in this embodiment includes a core shaft 110 and a driving member 120 disposed on the core shaft 110, wherein the driving member 120 includes an inner layer 121 and an outer layer 122, the inner layer 121 is made of a metal material and is fixedly secured to the core shaft 110, and the outer layer 122 is made of a polymer material and is fixedly secured to the inner layer 121.

The inner layer 121 is made of a metal material and may be fixed on the mandrel 110 by bonding or welding or other means, and the bonding strength between the two is very high, so that the inner layer 121 does not shift on the mandrel 110, and the outer layer 122 is connected with the mandrel 110 through the inner layer 121, which indirectly increases the connection area of the outer layer 122 and the mandrel 110, thereby enhancing the adhesion of the outer layer 122 on the mandrel 110, and reducing the possibility of the outer layer 122 loosening, wrinkling or shifting during stent delivery. It is understood that the "sleeving" described herein has two cases, one is that, with respect to the mandrel 110, the inner layer member 121 is an independent member, and the two are assembled into a whole after being processed respectively; secondly, in the processing process, the inner layer 121 and the mandrel 110 are integrally formed, but the inner layer 121 protrudes out of the outer surface of the mandrel 110.

Further, a void structure 123 may be formed on the inner layer 121, and the outer layer 122 partially or completely fills the void structure 123 to increase a connection area between the outer layer 122 and the inner layer 121.

In the present embodiment, the inner layer 121 may have various structures, and the preferred structure of the inner layer 121 will be described with reference to the accompanying drawings. It should be understood that the inner layer member 121 in the following embodiments is only an alternative implementation of the present invention, and should not limit the present invention.

As shown in fig. 2-4, in one embodiment, the inner layer 121 includes a plurality of coils that are hooped on the mandrel 110, and the plurality of coils are arranged along the axial direction of the mandrel 110. In this embodiment, since the coils may be made of metal wires with a circular or elliptical cross section, two adjacent coils may contact each other, so that a recessed portion with a cross section similar to a V shape may be formed between two adjacent coils, and the recessed portion constitutes the void structure 123. In other embodiments, the recess may also be in the shape of a U-shaped groove, a cube, a cuboid, or a hemispherical dimple, depending on the shape of the radial cross-section of the coil.

The outer layer 122 is formed on the outer surface of the coil by hot pressing and/or dip coating, etc., and is shaped and cooled by a mold. The hot pressing mode is as follows: firstly, sleeving a polymer tube on the inner layer member 121, sleeving a heat-shrinkable tube on the polymer tube, heating the heat-shrinkable tube, shaping by using a mold, so that the polymer tube is melted and permeates into the gap structure 123 of the inner layer member 121, and removing the heat-shrinkable tube after the polymer material is cooled and solidified. The material of the outer layer 122 includes any one or a combination of more of thermoplastic elastomers such as block polyether amide (Pebax) or Thermoplastic Polyurethane (TPU), silicone, nylon, acrylic polymers, and other polymer materials. The polymer material fills the void structure 123, so that the contact area between the outer layer 122 and the inner layer 121 is increased, and the connection between the two is strengthened. Even more, when the polymer material is not cured, the polymer material penetrates the surface of the mandrel 110 from between two adjacent coils, and simultaneously extends from two ends of the inner layer 121 to the surface of the mandrel 110, so that the outer layer 122, the inner layer 121 and the mandrel 110 can be tightly bonded, thereby further reducing the possibility of wrinkling, loosening and displacement of the outer layer 122. In other embodiments, the outer layer may be formed first, and the inner layer 121 and the outer layer 122 are connected by gluing or the like.

Alternatively, as shown in fig. 5, a plurality of coils may be distributed on the core shaft 110 at intervals, and a gap between two adjacent coils forms the void structure 123, in which case, the outer layer 122, the inner layer 121, and the core shaft 110 are all bonded to each other.

The inner member 121 is tightly wrapped around the mandrel 110 such that the inner member 121 exerts a greater radial pressure on the mandrel 110, and as the operator pushes the delivery guidewire 100, the friction between the mandrel 110 and the inner member 121 increases, which helps keep the inner member 121 and the mandrel 110 relatively stationary. The outer layer 122 covers the outer surface of the inner layer 121 to be connected to the core shaft 110 through the inner layer 121, and the outer layer 122 and the inner layer 121 have a large contact area therebetween. Further, the inner layer 121 may be fixedly connected to the mandrel 110 by welding (specifically, soldering or laser welding), the bonding strength between the inner layer 121 and the mandrel 110 may be much greater than that when the membrane structure is directly connected to the mandrel 110, and the outer layer 122 may wrap the inner layer 121 by dip coating or hot pressing, on one hand, the outer layer 122 has a contact surface with the mandrel 110 and the inner layer 121, so as to improve the bonding strength between the three, and prevent the outer layer 122 from loosening, shifting or deforming, on the other hand, due to the high bonding strength between the inner layer 121 and the mandrel 110, the whole driving member 120 may be prevented from loosening or shifting relative to the mandrel 110, thereby effectively preventing the stent from being unloaded. In other embodiments, the inner layer 121 may be fixedly connected to the core shaft 110 by bonding (gluing) or other connecting means.

Referring to fig. 6 and 7, in another embodiment of the present invention, the inner layer member 121 is a spiral structure formed by spirally winding a wire along the axis of the mandrel 110. Similar to the previous embodiment, for the inner layer 121 of the spiral structure, the wires of two adjacent turns may be in contact with each other or separated from each other.

Alternatively, the inner layer 121 in this embodiment may be wound by polymer wires or metal wires. For the inner layer 121 made of metal, the helical structure is soft and flexible, so that the whole delivery guidewire 100 has better flexibility.

Generally, the longer the stent to be delivered (i.e., the greater the axial dimension of the stent), the greater the length of the entraining member 120 disposed on the mandrel 110 so as to generate sufficient friction between the stent and the delivery guidewire 100. In this embodiment, the mandrel 110 may be provided with a plurality of driving members 120 to increase the total length of the driving members 120, and the plurality of driving members 120 may be spaced apart from each other along the axial direction of the mandrel 110.

Referring to fig. 8 and 9, in another embodiment of the present invention, the inner layer 121 is a tube net structure woven by threads, and the mesh holes of the tube net structure form the void structure 123.

In this embodiment, the mandrel 110 may be provided with only one driving member 120, or a plurality of driving members 120. For each entraining member 120, the wires used to weave the inner layer 121 should be as thin as possible, e.g., the diameter of the wires (or the cross-sectional width of the wires) is less than or equal to 0.001 inch. In addition, the number of braid intersections per inch of the inner layer 121 should not be excessive, and preferably, the number of braid intersections per 1 inch of the inner layer 121 may be between 15 and 50. As such, the entraining member 120 does not affect the flexibility of the delivery guidewire 100 while enhancing the securement of the connection to the mandrel 110.

Fig. 10 shows a schematic view of a further embodiment of the invention. Referring to fig. 10, one or more inner layers 121 are welded to the mandrel 110, and the inner layers 121 are metal pipes. In this embodiment, the metal tube has a tubular structure with a flat surface. The metal tube may be 0.3-2mm in length to avoid affecting the compliance of the pushwire 100. When there are at least two metal pipes, the outer layer 122 may be configured to entirely cover all of the metal pipes, and may extend to the mandrel 110, and may also cover a portion of the mandrel 110 exposed between the metal pipes (the portion constitutes the gap structure 123), or the outer layer 122 may be disposed on a single metal pipe (as shown in fig. 10), that is, the single outer layer 122 covers a single inner layer 121, different outer layers 122 respectively cover different inner layers 121, and the outer layer 122 may also partially cover the mandrel 110 between the metal pipes (the portion constitutes the gap structure 123). The wrapping of the outer layer 122 to the inner layer 121 may be accomplished by dip coating or hot pressing.

In other embodiments, the metal pipe may further be provided with a pit, a groove, or a through hole by laser etching or the like, so as to form more void structures 123, so as to further increase the contact area between the outer layer 122 and the inner layer 121, and improve the connection strength.

The inner layer member 121 described in the above embodiments may be made of a metal having no developability or a metal having developability. The metal without developability includes, but is not limited to, stainless steel, and the metal with developability includes, but is not limited to, platinum-tungsten alloy or platinum-iridium alloy. Preferably, the inner layer 121 is made of a metal (or radiopaque metal) with developability, so as to make the carrying member 120 have developability, and specifically, the material of the inner layer may be selected from one or more of platinum, gold, tungsten, platinum alloy, platinum-tungsten alloy, platinum-iridium alloy and platinum-nickel alloy, for example, the inner layer is made of platinum-tungsten alloy alone, or platinum-iridium alloy alone, or both platinum-tungsten alloy and platinum-iridium alloy (for example, the inner layer is woven by platinum-tungsten alloy wires and platinum-iridium alloy wires together to form the tube network structure). The advantage of setting up like this is, in transportation process, the operator can in time, accurately judge whether the support can also retrieve. Specifically, in actual use, the stent is sleeved over the delivery guidewire and compressed in a delivery tube having opposite first proximal and distal ends, with a visualization ring (not shown) disposed on the first distal end. In the conveying process, when the driving member 120 starts to coincide with the developing ring, if the bracket is pushed to the far end, the bracket can not be recovered any more, so that if the driving member 120 has developing performance, an operator can accurately perform positioning judgment through the developing device, and the operation of the operator is greatly facilitated.

Further, with continued reference to fig. 2, similar to the prior art delivery guidewire, the delivery guidewire 100 of the present embodiment may further include a first developing member 130 and a second developing member 140. The core shaft 110 has a second proximal end and a second distal end opposite to each other, the first developing member 130 may be a developing spring, the first developing member 130 is disposed at an end of the second distal end, the second developing member 140 is disposed on the core shaft 110, and the driving member 120 is disposed between the first developing member 130 and the second developing member 140. As such, in the treatment device, the holder is located between the first developing member 130 and the second developing member 140. During the process of delivering the stent, an operator can judge the position of the stent through the first developing member 130 and the second developing member 140.

The mandrel 110 may include at least one variable diameter section (not shown) and at least one constant diameter section (not shown). The constant diameter section and the variable diameter end are alternately arranged and connected with each other along the direction from the second proximal end to the second distal end. Any one of the variable diameter sections has a third proximal end and a third distal end which are opposite to each other, the diameter of the variable diameter section is gradually reduced from the third proximal end to the third distal end, and the diameter of the constant diameter section connected with the third proximal end is larger than that of the constant diameter section connected with the third distal end for the same variable diameter section. The whole conveying guide wire 100 is approximately in a conical structure through the arrangement of the reducing sections, so that the flexibility, the conveying force conductivity and the tracking performance of the conveying guide wire are improved, and the conveying and the releasing of the stent are facilitated.

The maximum outer diameter of the second developing member 140 may be approximately equal to or slightly smaller than the inner diameter of the conveying pipe. The second imaging member 140 has a fourth proximal end and a fourth distal end opposite to each other, and typically, the mandrel 110 on the side of the fourth proximal end of the second imaging member 140 has an outer diameter smaller than the inner diameter of the delivery tube, so that a cavity exists between the mandrel 110 and the delivery tube. If the cavity is large, the second distal end of the mandrel 110 may be unstable during pushing of the pushwire 100, which increases the pushing resistance of the pushwire 100. In this regard, the mandrel 110 is adjusted to make the mandrel 110 adjacent to the fourth proximal end of the second developing element 140 be a variable diameter section, and a reducing spring 150 is sleeved on the variable diameter section, and the reducing spring 150 is connected to the second developing element 140. The filling of the cavity between the mandrel 110 and the delivery tube by the reducing spring 150 ensures the stability of the second distal end of the mandrel 110 during the pushing through and at the same time does not negatively affect the compliance of the mandrel 110. Optionally, the second developing part 140 may include a body, a mounting through hole (not labeled in the figure) is axially disposed along the body, and a gap exists between a hole wall of a portion of the mounting through hole near the first proximal end and the mandrel 110 along a direction from the fourth proximal end to the fourth distal end, so that the distal end of the reducing spring 150 may be inserted into the second developing part 140, so that the reducing spring 150 is coaxial with the mandrel 110. In addition, for the embodiment of the present invention, the distance between two adjacent spring coils in the reducing spring 150 gradually increases along the direction from the second proximal end to the second distal end (i.e., the spring coils of the reducing spring 150 are more and more sparse in the direction from the second proximal end to the second distal end), so that the second distal end of the mandrel 110 can be ensured to have sufficient compliance without affecting the transmission of the pushing force.

It is a further object of the present invention to provide a treatment apparatus comprising a delivery tube, a medical implant and a delivery guidewire as in any of the previous embodiments. The medical implant is sleeved on the driving component, the conveying pipe is provided with an inner cavity which is axially communicated, the inner cavity is used for accommodating the conveying guide wire, and the wall of the inner cavity extrudes the medical implant, so that the medical implant is compressed and accommodated in the inner cavity. In the embodiment of the invention, the medical implant can be a self-expanding stent, in particular a woven stent or a cutting stent, and can also be a spring ring, a blood vessel plugging device and the like.

Further, a void structure 123 may be formed on the inner layer 121, and the outer layer 122 is at least partially embedded in the void structure 123. In the case where the contact area between the outer layer 122 and the medical implant is constant, the contact area between the outer layer 122 and the mandrel 110 and the inner layer 121 is increased to increase the friction force. In other words, the outer diameter of the outer layer 122 can be reduced by at least partially embedding the outer layer 122 in the void structure 123, thereby being applicable to delivery pipes of different inner diameters. The dimensions of the lumen in this embodiment may be selected in a variety of ways. For example, the radial dimension of the lumen may be between 0.017 inches and 0.029 inches, or the radial dimension of the lumen may be smaller, such as less than or equal to 0.027 inches, or even less than or equal to 0.021 inches.

In the embodiment of the present invention, the driving member 120 is disposed as two parts, namely, an inner layer member 121 and an outer layer member 122, the inner layer member 121 is of a metal structure and is fixedly sleeved on the mandrel 110, the outer layer member 122 is made of a polymer material and is fixedly sleeved on the inner layer member 121, and the inner layer member 121 indirectly enhances the bonding force between the outer layer member 122 and the mandrel 110, so that the driving member 120 is not easily loosened, folded or displaced during the stent delivery process, and the safety and reliability of the delivery guidewire 100 during the medical implant delivery process are improved.

Although the present invention is disclosed above, it is not limited thereto. Various modifications and alterations of this invention may be made by those skilled in the art without departing from the spirit and scope of this invention. Thus, if such modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include such modifications and variations.

Claims

1. A delivery guide wire is characterized by comprising a mandrel and a driving component arranged on the mandrel, wherein the driving component comprises an inner layer piece and an outer layer piece,

2. The pushwire of claim 1, wherein said inner layer has a void structure and said outer layer partially or completely fills said void structure.

3. The pushwire of claim 2, wherein said outer member is coupled to said mandrel at least partially through said void structure.

4. The pushwire of claim 2, wherein said inner member is provided with a recess in an outer surface thereof, said recess defining said void structure.

5. The pushwire of claim 2 or 3, wherein said inner layer member comprises a plurality of coils arranged in series along the axial direction of said core shaft, and said void structure is formed between two adjacent coils.

6. The pushwire of claim 2 or 3, wherein said inner member is a helical structure formed by a wire helically wound around the axis of said mandrel, said void structure being formed between two adjacent turns of said wire.

7. The pushwire of claim 2 or 3, wherein said inner layer is a tubular mesh structure woven from filaments, the pores of said tubular mesh structure constituting said void structure.

8. The pushwire of claim 7, wherein said wire has a diameter of less than or equal to 0.001 inches.

9. The pushwire of claim 7, wherein said inner layer comprises between 15 and 50 braid intersections per inch of length.

10. The pushwire of claim 1, wherein said inner member is at least one tubular structure, and said outer member partially or completely covers said inner member.

11. The pushwire of claim 10, wherein said tubular structure has a void structure disposed therein, said outer layer partially or completely filling said void structure;

or, the inner layer piece is at least two tubular structures, a gap structure is formed between the adjacent tubular structures, and the outer layer piece partially or completely fills the gap structure.

12. The pushwire of any of claims 1-4, wherein said inner member is made of a developable metallic material.

13. The delivery guidewire of claim 12, wherein the metallic material is selected from one or more of platinum, gold, tungsten, platinum-gold alloy, platinum-tungsten alloy, platinum-iridium alloy, and platinum-nickel alloy.

14. The pushwire of any of claims 1 to 4, wherein said inner member is welded to said mandrel or said inner member is glued to said mandrel.

15. The pushwire of any of claims 1 to 4, wherein said outer layer comprises any one or more of a block polyether amide resin, a thermoplastic polyurethane elastomer, silicone, nylon and an acrylic polymer.

16. The pushwire of any of claims 1 to 4, wherein said outer member covers said inner member and extends to join said mandrel.

17. The pushwire of any of claims 1 to 4, wherein said outer layer is formed on said inner layer by hot pressing and/or dip coating, or said inner and outer layers are bonded.

18. The pushwire of any of claims 1 to 4, wherein said inner layer is integrally formed with said mandrel.

19. The pushwire of any of claims 1-4, wherein said mandrel has at least two of said plurality of said.

20. A treatment device comprising a delivery tube, a medical implant, and a delivery guidewire as defined in any one of claims 1-19, the delivery tube having an axially-extending lumen for receiving the medical implant, and a wall of the lumen compressing the medical implant to cause the medical implant to be compressed; the compressed medical implant is sleeved on the driving component.

21. The treatment device of claim 24, wherein the lumen has a radial dimension in a range of 0.017 inches to 0.029 inches.