CN116850430A

CN116850430A - Guide wire

Info

Publication number: CN116850430A
Application number: CN202311133435.9A
Authority: CN
Inventors: 和田有功; 梁涛; 杨金鹏; 沈瑞静; 高晓慧; 殷慧梅; 比气俊辅
Original assignee: Essen Technology Beijing Co Ltd
Current assignee: Essen Technology Beijing Co Ltd
Priority date: 2023-09-05
Filing date: 2023-09-05
Publication date: 2023-10-10

Abstract

The application discloses a guide wire. The guide wire includes: a core wire having oppositely disposed proximal and distal ends; an inner coil body wound around the core wire; the outer coil body is wound on the core wire and sleeved on the outer side of the inner coil body; and a first engagement portion for engaging the distal end of the core wire, the distal end of the inner coil body, and the distal end of the outer coil body. The guide wire is sleeved with the double-layer coil bodies at the distal ends, and the two coil bodies are connected with the core wire through the joint parts only at the distal ends, so that physical property level differences generated outside the guide wire are avoided, the torsion control property, the support property and the pushing property of the guide wire are improved, in addition, the control performance of the distal ends of the guide wire is also improved, and obviously more excellent vascular selectivity is provided.

Description

Guide wire

Technical Field

The application relates to the field of interventional medical instruments, in particular to a guide wire.

Background

The guide wire is a medical instrument commonly used in interventional operations, plays a role in guiding and supporting a catheter, can assist the catheter to enter a lumen such as a blood vessel and a digestive tract, and guides the catheter to a lesion.

The guide wire is generally composed of a core wire and a coil body wrapped around the front end of the core wire. The support, flexibility, torque control, pushability of the guidewire are important indicators of its performance. An existing guide wire comprises two coil bodies, wherein the two coil bodies are sequentially sleeved on a core wire along the length direction of the core wire. In order to fix the two coil bodies, the guide wire needs to have a joint between the two coil bodies, fix the adjacent ends of the two coil bodies by the joint, and connect the two coil bodies to the core wire by the joint. However, such a joint structure is prone to physical property level differences, which results in a decrease in the torque control, support and pushability of the guide wire, and a decrease in the steering performance of the guide wire tip. At present, the joint part is subjected to grinding treatment, so that the smoothness is improved, the physical property level difference is reduced, but zero level difference cannot be realized.

Therefore, it is highly desirable to provide a guidewire that can minimize the physical property level difference, improve the processing efficiency and yield, and maintain the performance such as the support, flexibility, torque control, pushability, etc.

Disclosure of Invention

In view of the above, the application provides a guide wire, which reduces physical segment difference, improves processing efficiency, and simultaneously maintains better torsion control performance, flexibility and pushability, and has better vascular selectivity.

The examples of the present application can be realized by the following embodiments.

In a first aspect, the present application provides a guidewire comprising:

a core wire having oppositely disposed proximal and distal ends;

an inner coil body wound around the core wire;

the outer coil body is wound on the core wire and sleeved on the outer side of the inner coil body; the method comprises the steps of,

a first engagement portion for engaging the distal end of the core wire, the distal end of the inner coil body, and the distal end of the outer coil body.

Optionally, in some embodiments of the application, the guidewire further comprises a second engagement portion for engaging the proximal end of the inner coil body and the core wire.

Optionally, in some embodiments of the application, the length of the inner coil body is less than the length of the outer coil body.

Optionally, in some embodiments of the application, the proximal end of the inner coil body does not exceed the second engagement portion in the length direction of the core wire.

Optionally, in some embodiments of the application, the distal end of the core wire is located within the annular space of the inner coil body; and/or the number of the groups of groups,

the distal end of the inner coil body is positioned within the annular space of the outer coil body.

Optionally, in some embodiments of the present application, a wire diameter of the inner coil body is 35-65 μm; and/or the number of the groups of groups,

the outer diameter of the inner coil body is 0.15-0.35 mm; and/or the number of the groups of groups,

the pitch of the inner coil body is 5-20% of the wire diameter of the inner coil body.

Alternatively, in some embodiments of the application, the material of the inner coil body comprises a platinum iridium alloy.

Optionally, in some embodiments of the present application, the weight percentage of iridium in the platinum iridium alloy is 7-22%.

Optionally, in some embodiments of the present application, a wire diameter of the outer coil body is 35-65 μm; and/or the number of the groups of groups,

the screw pitch of the outer coil body is 5-20% of the wire diameter of the outer coil body; and/or the number of the groups of groups,

the outer diameter of the outer coil body is 0.34-0.36 mm.

Alternatively, in some embodiments of the application, the material of the outer coil body comprises stainless steel.

Optionally, in some embodiments of the present application, a wire diameter of the distal end of the core wire is 0.065-0.1 mm.

Optionally, in some embodiments of the present application, the material of the core wire includes a NiTi alloy or a NiTiCr alloy, wherein the NiTiCr alloy includes the following elements in weight percent: 50-60% of Ni, 0.15-0.35% of Cr and the balance of Ti.

According to the guide wire, the double-layer coil body is sleeved at the far end of the guide wire, and the two coil bodies are connected with the core wire through the joint part only at the far end, so that on one hand, the production difficulty is low, and the improvement of the production efficiency, the product qualification rate and the product quality stability is facilitated; on the other hand, the design mode omits the middle joint part, so that physical property section difference or protrusion caused by the joint of two coil bodies by solder and other welding agents does not appear on the surface of the coil body assembly, thereby avoiding physical property section difference generated outside the guide wire and improving the torsion control property, the support property and the pushing property of the guide wire.

Vascular selectivity is the ability of a guidewire to pass through blood vessels of different angles and is an important indicator for evaluating guidewire performance. By employing the unique double-layer coil body design of the guidewire according to the present application, the steering performance of the distal end is greatly enhanced, thereby providing better vascular selectivity. The guide wire reduces the physical property level difference to the maximum extent, improves the processing efficiency and the yield, and maintains the performances of supporting property, flexibility, torsion control property, pushing property and the like.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for the description of the embodiments will be briefly described below, and it is apparent that the drawings in the following description are only some embodiments of the present application, and that other drawings may be obtained according to these drawings, based on only their knowledge and skills, for a person skilled in the art.

FIG. 1 is a schematic view of a guide wire according to an embodiment of the present application;

FIG. 2 is a block diagram of a first vessel model used in the vessel selectivity test of Experimental example (II);

FIG. 3 is a torque transmissibility experimental graph of the guide wire of example 1 in experimental example (III);

FIG. 4 is a torque transmissibility experimental graph of an RTNS-Extra guide wire in experimental example (III);

FIG. 5 is a graph comparing bending strength of an RTNS-Extra guide wire of experimental example (IV) and a guide wire of example 1;

reference numerals:

100-a guide wire; 1-core wire; 11-shaping section; 12-transition section; 13-a support section; 14 pushing the segment; 2-an inner coil body; 3-an outer coil body; 41-a first joint; 42-a second joint; 43-third joint; 5-coating; 6-a rear section pipe body.

Detailed Description

The following description of the embodiments of the present application will be made clearly and completely with reference to the accompanying drawings, in which it is apparent that the embodiments described are only some embodiments of the present application, but not all embodiments. All other embodiments, which can be made by a person skilled in the art without making any inventive effort, are intended to be within the scope of the present application based on the embodiments of the present application. Furthermore, it should be understood that the detailed description is presented herein for purposes of illustration and description only, and is not intended to limit the application. In the present application, unless otherwise specified, terms such as "upper" and "lower" are used specifically to refer to the orientation of the drawing in the figures. In addition, in the description of the present specification, the term "including" means "including but not limited to". Various embodiments of the application may exist in a range of forms; it should be understood that the description in a range format is merely for convenience and brevity and should not be construed as a rigid limitation on the scope of the application; it is therefore to be understood that the range description has specifically disclosed all possible sub-ranges and individual values within that range. For example, it should be considered that a description of a range from 1 to 6 has specifically disclosed sub-ranges, such as from 1 to 3, from 1 to 4, from 1 to 5, from 2 to 4, from 2 to 6, from 3 to 6, etc., as well as single numbers within the range, such as 1, 2, 3, 4, 5, and 6, wherever applicable. In addition, whenever a numerical range is referred to herein, it is meant to include any reference number (fractional or integer) within the indicated range.

In the present application, "and/or" describing the association relationship of the association object means that there may be three relationships, for example, a and/or B may mean: a alone, a and B together, and B alone. Wherein A, B may be singular or plural.

In the present application, "at least one" means one or more, and "a plurality" means two or more. "at least one", "at least one" or the like refer to any combination of these items, including any combination of single item(s) or plural items(s). For example, "at least one (individual) of a, b, or c," or "at least one (individual) of a, b, and c," may each represent: a, b, c, a-b (i.e., a and b), a-c, b-c, or a-b-c, wherein a, b, c may be single or multiple, respectively.

The present application proposes a guide wire 100, see fig. 1, the guide wire 100 comprising a core wire 1, an inner coil body 2, an outer coil body 3 and a first joint 41. For convenience of description, the end of the guide wire 100, which is close to the operator when being operated, is set as a proximal end, and the end, which is relatively far from the operator, is set as a distal end, and the proximal and distal ends of the guide wire 100 coincide with the proximal and distal ends of the core wire 1 with which it is equipped; likewise, the proximal and distal ends of the two coil bodies are also in line with the core wire 1, the guide wire 100. Wherein, the inner coil body 2 is coil-shaped and is wound at the far end of the core wire 1; the outer coil body 3 is wound on the distal end of the core wire 1 and sleeved outside the inner coil body 2; the first engagement portion 41 is provided at the distal end of the core wire 1, in particular, the first engagement portion 41 is provided at the shaping section 11 of the core wire 1 for engaging the distal end of the core wire 1 remote from the end of the transition section 12, the distal end of the inner coil body 2 and the distal end of the outer coil body 3.

The material of the first joint 41 may be silver fiber solder, silver alloy solder, or the like.

The guide wire 100 provided by the application is improved in the far end, the double-layer coil body is sleeved at the far end, and the two coil bodies are connected with the core wire 1 through the joint part only at the far end, so that the production difficulty is low, the production efficiency, the product qualification rate and the product quality stability are improved, in addition, the middle joint part is omitted in the design mode, the physical property section difference or the protrusion caused by the welding flux such as tin material is not generated on the surface of the coil body assembly any more, the physical property section difference generated outside the guide wire 100 is avoided, the torsion control, the support and the pushing property of the guide wire 100 are improved, the control performance of the far end of the guide wire 100 is improved, and the vascular selectivity is better. In addition, the two coil bodies are sequentially sleeved at the far end of the core wire 1 from inside to outside, so that the clamping of the outer coil body 3 at the lesion is reduced. Moreover, when excessively torsionally controlled, accumulation of torsionally controlled at the junction between the conventional coil body and the coil body may cause product damage, which can be avoided by the existing designs.

Furthermore, in some embodiments, the guidewire 100 further comprises a second engagement portion 42, said second engagement portion 42 being adapted to engage the proximal end of the inner coil body 2 and the core wire 1. Specifically, the proximal end of the inner coil body 2 is pre-fixed with the core wire 1 by the second engagement portion 42. The material of the second joint 42 may be a lead-free tin alloy solder.

In some embodiments, the length of the inner coil body 2 is much smaller than the length of the outer coil body 3. The distal end of the inner coil body 2 is located in the inner space of the outer coil body 3, that is, the distal end of the outer coil body 3 is sleeved outside the inner coil body 2.

In some embodiments, the distal end of the inner coil body 2 is connected to the distal end of the core wire 1 and the distal end of the outer coil body 3 by a first joint 1, and the distal end of the inner coil body 2 does not exceed (not protrude from) the first joint 1 in the length direction; the proximal end of the inner coil body 2 is connected to the core wire 1 by a second joint 42, and accordingly, the proximal end of the inner coil body 2 does not exceed the second joint 42 in the length direction of the core wire 1.

In some embodiments, the distal end of the core wire 1 is located in the annular space of the inner coil body 2, i.e. the distal end of the inner coil body 2 is sleeved outside the core wire 1.

In other embodiments, the guidewire 100 further includes a third engagement portion 43, by which the proximal end of the outer coil body 3 is secured to the core wire 1. The material of the third joint 43 may be a lead-free tin alloy solder.

In some embodiments of the present application, the wire diameter of the inner coil body 2 is 35-65 μm; for example, it may be 35 μm, 36 μm, 37 μm, 40 μm, 42 μm, 45 μm, 47 μm, 48 μm, 49 μm, 50 μm, 51 μm, 52 μm, 53 μm, 55 μm, 60 μm, 65 μm or a value between any two of the above values. Optimizing the wire diameter of the inner coil body 2 helps to increase the wire diameter of the inner coil body 2 as much as possible while reducing the outer diameter of the inner coil body 2 so as to improve the developing effect thereof, and controlling the wire diameter within this range helps to balance the size requirement and developing effect of the inner coil body 2.

In some embodiments, the pitch of the inner coil body 2 is 5-20% of the wire diameter of the inner coil body 2, for example, may be 5%, 6%, 7%, 8%, 9%, 10%, 11%, 12%, 13%, 14%, 15%, 16%, 17%, 18%, 19%, 20% of the wire diameter thereof, and a value between any two of the above values. Optimizing the coil body pitch helps to reduce the tip load while controlling its manufacturing difficulty. As an example, when the wire diameter of the inner coil body 2 is 50 μm, the pitch of the inner coil body 2 may be 2.5 to 10 μm.

In some embodiments, the outer diameter of the inner coil body 2 is 0.15-0.35 mm; for example, it may be 0.15mm, 0.16mm, 0.2mm, 0.22mm, 0.25mm, 0.27mm, 0.29mm, 0.3mm, 0.31mm, 0.33mm, 0.35mm, or a value between any two of the above values. In this way, the volume of the inner coil body 2 is reduced.

In some embodiments, the material of the inner coil body 2 comprises a platinum alloy, which may include, for example, but not limited to, any one of platinum nickel alloy, platinum tantalum alloy, platinum gold alloy, platinum iridium alloy. In some embodiments, the material of the inner coil body 2 is preferably platinum iridium alloy, and the flexibility and workability of the material are improved and the developability of the inner coil body 2 is greatly improved by adding iridium element. Specifically, in the platinum iridium alloy, the weight percentage of iridium is 7% -22%, for example, 7% -10%, 8% -11%, 9% -12%, 7% -13%, 10% -15%, 13% -18%, 16% -19%, 17% -20%, 20% -22% and the like can be used. Thus, the development property is improved, and the hardness of the inner coil body 2 is ensured, and the balance between the development property and the distal load of the guide wire 100 is ensured.

In some embodiments, the wire diameter of the outer coil body 3 is 35-65 μm; for example, it may be 35 μm, 36 μm, 37 μm, 40 μm, 42 μm, 45 μm, 47 μm, 48 μm, 49 μm, 50 μm, 51 μm, 52 μm, 53 μm, 55 μm, 60 μm, 65 μm or a value between any two of the above values.

In some embodiments, the pitch of the outer coil body 3 is 5-20% of the wire diameter of the outer coil body 3, for example, may be 5%, 6%, 7%, 8%, 9%, 10%, 11%, 12%, 13%, 14%, 15%, 16%, 17%, 18%, 19%, 20% of the wire diameter, and a value between any two of the above values. The pitch of the coil body is optimized, so that the tip load is reduced, and the stress concentration is effectively relaxed. In this way, when the guide wire 100 is stuck at the lesion site, the damage of the outer coil body 3 caused by stress concentration can be avoided, which is conducive to prolonging the service life thereof, and at the same time, is also conducive to controlling the manufacturing difficulty of the outer coil body 3, so that the outer coil body 3 is easy to process and manufacture.

In some embodiments, the outer diameter of the outer coil body 3 is 0.34 mm-0.36 mm; for example, it may be 0.34mm, 0.342mm, 0.344mm, 0.345mm, 0.347mm, 0.35mm, 0.352mm, 0.355mm, 0.358mm, 0.36mm and values between any two of the above.

In some embodiments, the material of the outer coil body 3 may include, but is not limited to, a stainless steel material, such as SUS302, SUS304V, SUS316L, SUSWPB, and the like.

In the present application, the core wire 1 is substantially linear, and the core wire 1 includes a pushing section 14, a supporting section 13, a transition section 12, and a shaping section 11, which are disposed in this order in a direction from the proximal end to the distal end.

The shaping section 11 extends from the proximal end to the distal end, and has a flat cross section, specifically, the width (i.e., the dimension perpendicular to the length direction of the core wire 1) is 120-155 μm, and the diameter of the distal end of the shaping section 11 before flattening is defined as the diameter dimension of the distal end of the core wire 1 according to the present application, i.e., the diameter of the distal end of the shaping section before flattening is 0.065-0.1 mm, such as 0.065-0.068 mm, 0.068-0.070 mm, 0.070-0.075 mm, etc. In this way, the breaking strength can be made greater than 250gf while ensuring a sufficiently soft head end load of 1g or less. Through adjusting the distal end wire diameter (the width of the flat section) of the core wire 1, the core wire 1 not only can adapt to the smaller inner cavity space of the inner coil body 2 and is inserted into the inner cavity space, but also can help to reduce the tip load and be easier to control by limiting the plastic shape to two dimensions, and can have certain breaking strength, maintain the balance between the breaking strength and the distal end load, help to alleviate the physical property level difference and achieve the balance of accessibility and supportability.

It will be appreciated that the support section 13, the transition section 12 and the shaping section 11 may be of a unitary construction, and may be formed from a single core during actual processing, for example, the distal end of the core may be first reduced to a desired size, and then flattened to form the shaping section 11.

In some embodiments of the application, the material of the core wire 1 comprises NiTi alloy.

In other embodiments of the application, the material of the core wire 1 comprises a NiTiCr alloy.

Further, as a preferred embodiment, the NiTiCr alloy includes the following elements in weight percent: 50-60% of Ni, 0.15-0.35% of Cr and the balance of Ti. The Cr content in the alloy is 0.15 to 0.35wt%, for example, 0.15wt%, 0.17wt%, 0.18wt%, 0.19wt%, 0.2wt%, 0.21wt%, 0.22wt%, 0.24wt%, 0.25wt%, 0.27wt%, 0.28wt%, 0.3wt%, 0.31wt%, 0.35wt% and values between any two of the above values, etc. Further, the Cr content is preferably 0.18-0.32wt%; further, the Cr content is more preferably 0.2 to 0.3wt%, and in this range, it contributes to further improving the strength of the material to increase the strength thereof, and improves the bending rigidity, torque control transmission and operability of the guide wire 100 in a reasonable range, making it more suitable for use as a core wire of the guide wire 100. The Ni content is 50 to 60wt%, for example, 50wt%, 51wt%, 52wt%, 53wt%, 54wt%, 55wt%, 56wt%, 57wt%, 58wt%, 59wt%, 60wt%, and a value between any two of the above values, etc. Further, the Ni content is preferably 52 to 58wt%. By adopting NiTiCr alloy added with chromium as a manufacturing material, the rigidity of the core wire 1 is effectively improved, and thus, the core wire 1 with smaller wire diameter also has higher breaking strength; in particular, when used in the guide wire 100 shown in fig. 1, the connection between the core wire 1 and the nitinol tube for holding is increased in rigidity due to the core wire 1, and sufficient connection strength is required only by the insertion and fitting of the core wire 1 and the tube.

The core wire material can be prepared according to a method of alloy materials conventional in the art, and specifically: and (3) taking all the raw material powders, ball-milling, mixing, heating, melting, removing residues on the surface layer of the solution, casting, forming, annealing, and pickling.

Further, the guidewire 100 also includes a posterior segment of the tube 6. The surface of the rear pipe body 6 is coated with a coating 5, and the material of the coating 5 includes, but is not limited to, any one of polyethylene, polypropylene, polyvinyl chloride, polytetrafluoroethylene, polyester, polyamide and polyimide.

Furthermore, in some embodiments, the guide wire 100 is of GW1, and accordingly, the rear tube 6 and the core wire 1 are made of the same material and are integrally formed into a whole; in other embodiments, referring to fig. 1, the guide wire 100 is of GW2 gauge, and accordingly, the material of the rear tube 6 may be a stainless steel material. The guidewire 100 also includes a connector (not shown) by which the proximal end of the core wire 1 is connected to the posterior segment tube body 6, which may be a nitinol tube.

The guide wire of the present application may be assembled with reference to conventional manufacturing processes in the art, and will not be described in detail herein.

The technical solutions and effects of the present application will be described in detail by way of specific examples, comparative examples and experimental examples, which are only some examples of the present application, and are not intended to limit the present application in any way.

Example 1

The guide wire of this embodiment has a GW 2-specification structure as shown in FIG. 1, and has a total length of 190cm. The guide wire comprises a core wire, an inner coil body, an outer coil body, a rear section tube body, a first joint part, a second joint part and a third joint part. Wherein:

the material of the core wire is NiTi alloy; the diameter of the far end wire is 0.065mm;

the material of the inner coil body is platinum iridium alloy, and the weight percentage of iridium is 15%; the inner coil body has a wire diameter of 45 μm, a pitch of 15%, an outer diameter of 0.35mmmm and a length of 25mm;

the outer coil body is made of SUS304WPB stainless steel; the wire diameter is 60 mu m, the screw pitch is 12%, the outer diameter is 0.35mm, and the length is 200mm;

and providing a core wire formed by machining, and connecting the proximal end of the core wire with a stainless steel rear-section tube body to form a main body structure of GW 2. Then the inner coil body and the outer coil body are assembled to the distal end of the core wire in sequence, the distal end of the inner coil body, the distal end of the outer coil body and the distal end of the core wire are joined by a first joining portion (silver fiber), the proximal end of the inner coil body is joined to the surface of the core wire by a second joining portion (soldering), and the proximal end of the outer coil body is joined to the surface of the core wire by a third joining portion (soldering). Finally, the guide wire is cleaned by purified water and acetone in an ultrasonic way to remove impurities and greasy dirt of the wire winding part, and then hydrophilic coating is carried out on the wire winding part (namely the inner coil body and the outer coil body) of the guide wire, and the guide wire product is obtained after solidification.

Example 2

The scheme of this example is basically the same as that of example 1, except that in this example, the material of the core wire is changed to a NiTiCr alloy, wherein Ni 52wt%, cr 0.24wt%, and the balance is Ti.

Experimental example

Experimental example 1

The core filaments of examples 1 and 2 were subjected to head-end load and tensile testing, and the results are reported in Table I.

List one

As can be seen from the above table, the example 2 core wire provides higher head end load and peak tension, and therefore the use of a nickel titanium alloy core wire containing chromium elements, in combination with the process of making the guide wire, reduces the risk of the guide wire breaking.

Experimental example 2

Three commercially available guidewires were used as a control group, and vascular selectivity was compared with the guidewires prepared in this example.

Three common guide wires sold in the market are temporarily called an RTNS guide wire, a BMW guide wire and an APT guide wire, wherein the inner coil body and the outer coil body are sequentially sleeved outside the guide wire from the far end to the near end along the length direction of the guide wire, and the near end of the inner coil body and the far end of the outer coil body are fixed on the guide wire through a joint piece;

the detection method comprises the following steps: a first vessel model as shown in fig. 2 is provided, which has a main pipe extending in the horizontal direction and six branch pipes (numbered 1, 2, 3, 4, 5, 6 in order from left to right) respectively communicating with the main pipe, and the angles of the six branch pipes with the horizontal direction are 90 °, 80 °, 70 °, 60 °, 50 °, 40 ° in order from left to right. Two guide wires of the same model are adopted for testing, the number of a pipeline into which the two guide wires can enter is inspected, and the average value of the test values of the two guide wires in each group is taken as a result to be recorded in a second table.

Watch II

From Table two above, the guide wires of examples 1 and 2 have higher vascular selectivity, demonstrating the advantage of the guide wire of the present application in high vascular selectivity.

Experimental example (III)

Torque transmissibility was measured using RTNS guidewires and example 2 guidewires used in the above experiments. The detection method comprises the following steps: a second vessel model, as shown in fig. 3, is provided with a plurality of bends, and a guide wire is inserted and pushed from the entrance of the bend, and the entry is observed, as shown in fig. 3 and 4.

Results: from the figure, it can be seen that the RTNS guide wire enters the first bend, and the guide wire of the embodiment 2 can smoothly reach the third bend, which shows that the guide wire provided by the application has higher torque transmissibility.

Experimental example (IV)

The RTNS guide wire used in the above experiment and the guide wire of example 2 were taken for flexural strength test. The detection method comprises the following steps: the three-point bending experiment is carried out on the guide wire, specifically, the three-point bending tool is firstly put on a universal pulling machine, then the coil part of the guide wire is subjected to three-point bending test at intervals from the head end, and the test length covers the whole coil length. The results are shown in FIG. 5.

Results: compared with the commercially available guide wire, the guide wire of the embodiment has no sudden increase of bending resistance about 30mm, has more stable and controllable bending strength and better torsion control property.

In summary, compared with the commercially available guide wire, the application adopts the sleeved double-coil body structure, avoids the physical segment difference of the joint between the double-coil bodies, and has stronger rigidity than a single coil in a manner of arranging the double-coil bodies at the far end, thereby increasing the torque transmissibility of the guide wire.

The guide wire provided by the embodiment of the application is described in detail, and specific examples are applied to illustrate the principle and the implementation of the application, and the description of the above examples is only used for helping to understand the method and the core idea of the application; meanwhile, as those skilled in the art will have variations in the specific embodiments and application scope in light of the ideas of the present application, the present description should not be construed as limiting the present application.

Claims

1. A guidewire, comprising:

a core wire having oppositely disposed proximal and distal ends;

an inner coil body wound around the core wire;

2. The guidewire of claim 1, further comprising a second engagement portion for engaging the proximal end of the inner coil body and the core wire.

3. The guidewire of claim 2, wherein the proximal end of the inner coil body does not exceed the second engagement portion in a length direction of the core wire.

4. The guidewire of claim 1, wherein the distal end of the core wire is located within the annular space of the inner coil body; and/or the number of the groups of groups,

5. The guide wire according to claim 1, wherein the wire diameter of the inner coil body is 35-65 μm; and/or the number of the groups of groups,

6. The guidewire of claim 1, wherein the material of the inner coil body comprises a platinum iridium alloy.

7. The guidewire of claim 6, wherein the platinum iridium alloy comprises 7-22% iridium by weight.

8. The guidewire of claim 1, wherein the outer coil body has a wire diameter of 35-65 μm; and/or the number of the groups of groups,

the outer diameter of the outer coil body is 0.34-0.36 mm.

9. The guidewire of claim 1, wherein the material of the outer coil body comprises stainless steel.

10. The guidewire of claim 1, wherein the distal end of the core wire has a wire diameter of 0.065-0.1 mm.

11. The guidewire of claim 1, wherein the material of the core wire comprises a NiTi alloy or a NiTiCr alloy, wherein the NiTiCr alloy comprises the following elements in weight percent: 50-60% of Ni, 0.15-0.35% of Cr and the balance of Ti.