CN116173375A - Pre-expansion guide wire - Google Patents

Abstract

The embodiment of the disclosure provides a pre-expansion guide wire, which comprises a core wire, wherein the diameter of the core wire gradually decreases from a proximal end to a head end, the core wire comprises a distal core wire and a proximal core wire, the distal core wire at least comprises a first part close to the head end and a second part far away from the head end, an expansion part is arranged in the second part, the diameter of the expansion part is larger than the diameters of two sides of the expansion part, a first sheath is arranged on the outer side of the distal core wire of the first part, a second sheath is arranged on the outer side of the distal core wire of the second part, the distal core wire and the proximal core wire are connected in a resistance welding and/or bonding mode, and a metal tube is arranged on the outer side of the connection part of the distal core wire and the proximal core wire. The embodiment of the disclosure can pre-dilate the narrow part of the blood vessel based on the dilated part, is convenient for other interventional instruments to pass through the lesion part, and has simple preparation, easy realization and lower cost.

Description

Pre-expansion guide wire

Technical Field

The present disclosure relates to the field of medical devices, and in particular to a pre-expanded guidewire.

Background

Cardiovascular and cerebrovascular diseases are healthy first killers in modern society, the number of people dying from cardiovascular and cerebrovascular diseases every year in the world is up to 1500 ten thousand people, and various causes of death are the first place. The interventional therapy is the main means for clinically treating coronary atherosclerotic heart disease at present, and can effectively treat stenosis by interventional implantation of a balloon catheter or a stent, recover normal blood circulation and ensure blood supply.

The guide wire is an indispensable matching product in interventional medical instruments, has been widely applied to medical interventional operations, and plays a role in guiding and positioning various interventional medical catheters and implantation instruments entering human organs. In the process of implementing the operation, firstly, a guide wire is required to enter a true lumen of a blood vessel, then, the balloon of the preassembled stent is conveyed to a vascular lesion site along the guide wire, if the lesion site is severely narrowed, the balloon can not pass through a narrow section, therefore, the narrow site is required to be pre-expanded by using an expanding guide wire, and then the balloon is introduced, so that the subsequent operation is performed, the operation time can be shortened, and the operation success rate can be improved.

Furthermore, there are 2 designs for the core wire tip of the prior art guide wire: 1) The tip of the core wire does not reach the end of the guide wire (Shaping fabric design), and as the core wire does not reach the end of the guide wire, when the proximal end of the guide wire is rotated, torsion force cannot be transmitted to the end of the guide wire, so that the phenomenon of tail flick of the guide wire exists, and the torsion control of the guide wire is insufficient; 2) The core wire tip to the guide wire tip end (core to tip design) is usually very small in diameter in order to ensure softness of the guide wire end, so that the guide wire end has a risk of easy falling off and breakage.

Disclosure of Invention

It is an aim of embodiments of the present disclosure to provide a pre-expanded guidewire to address the problems of the prior art. In order to solve the above technical problems, the embodiments of the present disclosure adopt the following technical solutions:

the disclosed embodiments provide a pre-expansion guide wire, which includes a core wire, the diameter of the core wire gradually decreases from a proximal end to a head end, the core wire includes a distal core wire and a proximal core wire connected by resistance welding and/or bonding, the distal core wire includes at least a first portion near a head end and a second portion far away from the head end, an expansion portion is disposed in the second portion, the diameter of the expansion portion is greater than the diameter of both sides thereof, a first sheath is disposed outside the distal core wire of the first portion, and a second sheath is disposed outside the distal core wire of the second portion.

In some embodiments, the diameter of the expansion site increases gradually from the distal end to the proximal end.

In some embodiments, the second sheath is welded or hot-melt connected to the distal core wire, and the second sheath is made of a metal material when the welding method is adopted, and is a hot-melt polymer sheath when the hot-melt method is adopted.

In some embodiments, a safety mesh is disposed between the distal core wire and the first sheath, the first sheath covering at least a portion of the safety mesh.

In some embodiments, the safety mesh is made by braiding wires, either round wires or flat wires, into different mesh densities or different sizes.

In some embodiments, the first sheath is a spring coil sheath, a polymer sheath, or a combination thereof.

In some embodiments, where the first sheath is a spring coil sheath, the spring coil sheath is made by connecting a developing spring that covers a portion of the safety mesh and a stainless steel spring that covers other portions of the distal core wire than the safety mesh portion.

In some embodiments, a hydrophilic coating is disposed on the first jacket outer surface.

In some embodiments, a metal tube is disposed outside of the portion where the distal core wire and the proximal core wire are connected, the metal tube being connected to the distal core wire and the proximal core wire by an adhesive.

In some embodiments, the proximal core wire has a stiffness that is greater than the stiffness of the distal core wire.

The embodiment of the disclosure can pre-dilate the narrow part of the blood vessel based on the dilated part, is convenient for other interventional instruments to pass through the lesion part, and has simple preparation, easy realization and lower cost. When the pre-expansion guide wire reaches the position of the stenosis, the head end of the pre-expansion guide wire smoothly passes through the stenosis due to the small diameter, the diameter of the expansion part gradually increases, the stenosis is expanded due to the radial supporting function, and the expansion part of the pre-expansion guide wire is smooth and soft in transition and does not cause trauma to blood vessels.

Drawings

In order to more clearly illustrate the embodiments of the present disclosure or the technical solutions in the prior art, the drawings that are required to be used in the embodiments or the description of the prior art will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments described in the present disclosure, and other drawings may be obtained according to these drawings without inventive effort to a person of ordinary skill in the art.

FIG. 1 is a schematic view of a pre-expanded guidewire according to an embodiment of the present disclosure;

FIG. 2 is a schematic cross-sectional view of a pre-expanded guidewire at position A-A in accordance with an embodiment of the present disclosure;

FIG. 3 is a schematic view of the structure of a pre-expanded guidewire according to an embodiment of the present disclosure;

FIG. 4 is a schematic view of the structure of a pre-expanded guidewire according to an embodiment of the present disclosure;

FIG. 5 is a schematic view of a developing spring in a pre-expanded guidewire according to one embodiment of the present disclosure;

FIG. 6 is a force-bearing schematic view of a safety mesh in a pre-expanded guidewire according to an embodiment of the present disclosure;

FIG. 7 is a force-bearing schematic view of a safety mesh in a pre-expanded guidewire according to an embodiment of the present disclosure;

FIG. 8 is a schematic illustration of a head end softness test of a pre-expanded guidewire according to an embodiment of the present disclosure;

FIG. 9 is a graph of head end softness and breaking force test results for a pre-expanded guidewire according to an embodiment of the present disclosure;

FIG. 10 is a schematic illustration of the connection of the core wire interior of a pre-expanded guidewire according to another embodiment of the present disclosure;

FIG. 11 is a schematic illustration of the connection of the core wire interior of a pre-expanded guidewire according to another embodiment of the present disclosure;

fig. 12 is a schematic illustration of connection inside a core wire of a pre-expanded guidewire according to another embodiment of the present disclosure.

Reference numerals:

3-an expansion site; 7-a second sheath; 10-core wire; 101-distal core wire; 102-proximal core wire; 103-a metal tube; 11-a safety net; 12-a first sheath; 13-hydrophilic coating; 14-developing spring; 15-stainless steel spring.

Detailed Description

Various aspects and features of the disclosure are described herein with reference to the drawings.

It should be understood that various modifications may be made to the embodiments of the application herein. Therefore, the above description should not be taken as limiting, but merely as exemplification of the embodiments. Other modifications within the scope and spirit of this disclosure will occur to persons of ordinary skill in the art.

The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments of the disclosure and, together with a general description of the disclosure given above and the detailed description of the embodiments given below, serve to explain the principles of the disclosure.

These and other characteristics of the present disclosure will become apparent from the following description of a preferred form of embodiment, given as a non-limiting example, with reference to the accompanying drawings.

It should also be understood that, although the present disclosure has been described with reference to some specific examples, a person skilled in the art will certainly be able to achieve many other equivalent forms of the present disclosure, having the characteristics as set forth in the claims and hence all coming within the field of protection defined thereby.

The above and other aspects, features and advantages of the present disclosure will become more apparent in light of the following detailed description when taken in conjunction with the accompanying drawings.

Specific embodiments of the present disclosure will be described hereinafter with reference to the accompanying drawings; however, it is to be understood that the disclosed embodiments are merely examples of the disclosure, which may be embodied in various forms. Well-known and/or repeated functions and constructions are not described in detail to avoid obscuring the disclosure in unnecessary or unnecessary detail.

Therefore, specific structural and functional details disclosed herein are not intended to be limiting, but merely serve as a basis for the claims and as a representative basis for teaching one skilled in the art to variously employ the present disclosure in virtually any appropriately detailed structure.

The specification may use the word "in one embodiment," "in another embodiment," "in yet another embodiment," or "in other embodiments," which may each refer to one or more of the same or different embodiments in accordance with the disclosure.

Embodiments of the present disclosure relate to a guidewire, as shown in fig. 1 and 2, fig. 1 shows a schematic structural view of a pre-expanded guidewire, fig. 2 shows a schematic sectional view of the pre-expanded guidewire at A-A position, the pre-expanded guidewire includes a core wire 10, the core wire 10 is a core portion of the pre-expanded guidewire, and is located in an inner layer of the pre-expanded guidewire and extends from a proximal end of the pre-expanded guidewire to a distal end of the pre-expanded guidewire to a tip end of the pre-expanded guidewire, where the proximal end refers to a portion near an operator, the distal end refers to a portion far away from the operator, and the tip end refers to an end position of the distal end, and may be configured in a circular or tip shape. In this embodiment, the overall length of the core wire 10 is preferably 100-400cm.

Specifically, as further shown in fig. 1 and 2, the diameter of the core wire 10 varies along the length, and in one embodiment, the diameter of the core wire 10 gradually decreases from the proximal end to the distal end to the head end, so that the proximal end of the pre-expansion guide wire is convenient for a doctor to operate, and the head end of the pre-expansion guide wire is soft and is not easy to damage a blood vessel after entering a human body.

Further, the core wire 10 comprises two parts, namely a distal core wire 101 located at the distal end of the pre-expansion guide wire and up to the head end of the pre-expansion guide wire, and a proximal core wire 102 located at the proximal end of the pre-expansion guide wire, wherein the distal core wire 101 and the proximal core wire 102 can be manufactured by grinding processes, wherein the distal end of the proximal core wire 102 is connected with the proximal end of the distal core wire 101, and the diameter of the proximal core wire 102 is generally larger than the diameter of the distal core wire 101.

The expansion part 3 is arranged on the distal core wire 101, so that the core wire 10 has a pre-expansion effect through the expansion part 3, the expansion part 3 is positioned on the distal core wire 101 near the region of the proximal core wire 102, the length of the expansion part 3 can be set to be 5-20mm, the diameter of the expansion part 3 is larger than the diameters of two sides of the expansion part, the expansion part takes on the shape of expanding the diameter of a local region, and the transition of the expansion part 3 is very smooth and soft and does not cause trauma to blood vessels.

Of course, the desired expansion may be sized according to the lesion need, for which purpose the diameter of the expansion site 3 may be adjusted, preferably the diameter of the expansion site 3 is 0.36-0.80mm. When the pre-expansion guide wire passes through a blood vessel, the diameter of the expansion part 3 is increased, so that a narrow part in the blood vessel is expanded due to radial supporting effect, and the pre-expansion guide wire can pass smoothly.

Preferably, the diameter of the expansion part 3 is gradually increased from the distal end to the proximal end, and the stenosis is expanded due to the radial support based on the gradual increase of the diameter of the expansion part 3, so that the expansion part 3 on the pre-expansion guide wire can pass through the stenosis in the blood vessel more smoothly.

According to the embodiment of the disclosure, the vascular stenosis part can be pre-dilated by arranging the dilatation part, so that other interventional instruments can pass through the lesion part conveniently, and the transition at the dilatation part is smooth, soft and atraumatic. In addition, the preparation method is simple, easy to realize and low in cost.

As shown in fig. 3 and 4, fig. 3 and 4 show a schematic structural diagram of another pre-expanded guide wire, which is different from the above embodiment in that the core wire 10 is linear in the above embodiment, and in another embodiment, the distal end of the distal core wire 101 is bent to adapt to different clinical lesion requirements.

The distal core wire 101 may have a relatively high strength, and the high-strength distal core wire 101 may provide a good supporting force and pushing force to the pre-expansion guide wire, considering that the diameter of the distal end of the distal core wire 101 is very small so as to provide the pre-expansion guide wire with a good flexibility, and further, the distal end of the distal core wire 101 may have a tapered shape, a parabolic shape, a streamline shape, or any other structure.

Further, the core wire 10 may be made of a single material or a composite material, and in the case where the core wire 10 is made of a single material, for example, a stainless steel material is used. However, although the stainless steel material has strong supporting property and good pushing property, the stainless steel material has large rigidity and is easy to deform, so that the flexibility and the deformation resistance are weak, the operability of the pre-expansion guide wire is poor, the pre-expansion guide wire cannot quickly and safely reach a lesion part, and the operation risk is increased; if the nickel-titanium alloy material is adopted, the nickel-titanium alloy material has good elasticity and small rigidity, so that the nickel-titanium alloy material has excellent flexibility and deformation resistance, but has weak supporting force and poor pushing property, and can influence subsequent smooth release of the balloon, the bracket and other instruments, thereby increasing the operation risk.

To this end, the distal core wire 101 and the proximal core wire 102 are made of different materials, wherein the distal core wire 101 may be made of any material that has good resistance to deformation and is suitable for use as a guide wire, including but not limited to one of nickel-titanium alloy, fe-Ni alloy, or Ti-Ni-X alloy; the proximal core wire 102 may be made of any material that is supportive, stiff and suitable for use as a guidewire, including but not limited to 304 stainless steel, 316 stainless steel, cobalt-based alloys, fe-Mn alloys, cu-Zn alloys. For example, the distal core wire 101 at the distal end may be made of a nickel-titanium alloy, which has high resistance to deformation, and the proximal core wire 102 at the proximal end may be made of 304 stainless steel, which has good support and high rigidity. Fabrication of the distal core wire 101 and the proximal core wire 102 may be accomplished using physical grinding or chemical etching after the materials are selected.

The distal core wire 101 and the proximal core wire 102 may be formed by any two or more materials described above and connected, where the connection is one or more of resistance welding, brazing, ultrasonic welding, laser welding, adhesive, and snap fit.

In a specific embodiment, as shown in fig. 10 and 11, the core wire 10 includes a distal core wire 101 and a proximal core wire 102, where the distal core wire 101 is located at the distal end of the pre-expansion guide wire and extends to the head end of the pre-expansion guide wire, and the proximal core wire 102 is located at the proximal end of the pre-expansion guide wire, and the distal end of the proximal core wire 102 is connected to the proximal end of the distal core wire 101, where the proximal core wire 102 has a rigidity greater than that of the distal core wire 101, and the proximal core wire 102 is made of, for example, a stainless steel material, and the distal core wire 101 is made of, for example, a nickel-titanium alloy material, where the distal core wire 101 and the proximal core wire 102 are connected together by resistance welding and bonding, and where, for example, the core wires of these 2 materials may be connected together by bonding, as shown in fig. 10, or by direct welding, as shown in fig. 11.

Specifically, the resistance welding can promote torque transmission of the pre-expanded guide wire, and the bonding can avoid the problem that when the guide wire is bent due to different rigidities of the distal core wire 101 and the proximal core wire 102, the guide wire is easy to break due to stress concentration at a welding position, so that the safety of the guide wire is improved. The proximal core wire 102 with better rigidity can provide good supporting force and pushing force for the pre-expansion guide wire, the distal core wire 101 with better elasticity can provide good deformation resistance and flexibility for the pre-expansion guide wire, the core wire such as nickel-titanium alloy and the core wire of stainless steel are connected together in a direct welding and bonding mode, and the distal end of the pre-expansion guide wire has excellent deformation resistance and flexibility by combining the two material characteristics, and meanwhile, the proximal end has better supporting property and pushing property, so that torsion control property and safety of the pre-expansion guide wire are improved.

However, if the direct bonding is adopted, as shown in fig. 10, since the 2 materials are overlapped with each other, i.e. not on the same line, when the portion is in a bent state, the torsion is decomposed at the portion when the proximal end of the pre-expansion guide wire is rotated, i.e. the torsion transmission cannot realize 1:1 transmission, and if the direct bonding is adopted, as shown in fig. 11, because the 2 materials are different in rigidity, when the portion is in a bent state, stress concentration is easily generated, bending is caused at the welding portion, and thus fracture risk occurs. After butt welding, the two materials have low coaxiality, namely are not on the same line and are not bent, the torsion control transmission of the pre-expansion is affected, and the operation time is increased. For this purpose, a combination of resistance welding and adhesive bonding may be used.

For this purpose, further, a metal tube 103 is provided outside the connection portion of the distal core wire 101 and the proximal core wire 102, specifically, the metal tube 103 is connected to the distal core wire 101 and the proximal core wire 102 by an adhesive, and by the metal tube 103, it is possible to avoid a problem that when the guide wire is bent due to the difference in rigidity of the 2-stage core wire, stress concentration is easily caused at the welding point to break.

In a specific embodiment, as shown in fig. 12, the distal core wire 101 and the proximal core wire 102 are connected together by, for example, resistance welding, and then the metal tube 103 is bonded together with the distal core wire 101, the proximal core wire 102 and the metal tube 103 under the action of an adhesive, so that the pre-expansion guide wire has excellent operability. The distal core wire 101 and the proximal core wire 102 herein have a length of 100-400cm, and the metal tube 103 herein may be made of any material having high resistance to deformation, including but not limited to nickel-titanium alloy, fe-Ni alloy or Ti-Ni-X alloy; the adhesive herein may be made of any material that has good connectivity, including but not limited to one or more of AB glue, shellac, solder.

As further shown in fig. 1 and 2, a sheath for protecting the core wire 10 may also be provided outside the distal core wire 101, further, the sheath at different positions of the distal core wire 101 may differ, wherein the distal core wire 101 here comprises at least a first part close to the head end and a second part remote from the head end, wherein the expansion site 3 is located in the second part, wherein a first sheath 12 is provided outside the distal core wire 101 of the first part, and wherein a second sheath 7 is provided outside the distal core wire 101 of the second part, wherein the second sheath 7 is provided at least in particular on the expansion site 3. In one embodiment, the expansion site 3 is located 1-20mm from the proximal end of the first sheath 12.

Further, a safety net 11 is disposed between the distal core wire 101 and the first sheath 12, where the safety net 11 is sleeved on the distal core wire 101 and connected to the head end of the distal core wire 101, and the core wire 10, the safety net 11 and the first sheath 12 are coaxially disposed, where the first sheath 12 covers the whole part of the safety net 11, and may cover other parts of the first part of the distal core wire 101 except for the part of the safety net 11. A hydrophilic coating 13 is disposed on the outer surface of the first sheath 12, and the hydrophilic coating 13 may have a coating area larger than the coverage area of the first sheath 12.

As mentioned above, the first sheath 12 covers part of the distal core wire 101 and the entire safety net 11, and the first sheath 12 may be in the form of a spring coil sheath, a polymer sheath or a mixture of both, but other suitable materials may be used.

In this embodiment, as shown in fig. 1, when the first sheath 12 is a spring ring sheath, specifically, the spring ring sheath is made by connecting a developing spring 14 and a stainless steel spring 15, where the connection may be one or more of resistance welding, soldering, ultrasonic welding, laser welding, adhesive bonding, and snap fitting. In one embodiment, the developing spring 14 and the stainless steel spring 15 may be connected by laser welding to form the spring ring sheath, where the current set during the manufacturing process is 80-100A, the pulse width is 4.0-6.0ms, the frequency is 6-8Hz, and the welding time is 1-5s.

Further, as shown in fig. 1 in combination with fig. 5, the developing spring 14 is disposed near the distal end of the pre-expansion guide wire, and has a developing function, and can cover the portion of the safety net 11, preferably, the developing spring 14 is made of at least one of platinum tungsten alloy, platinum nickel alloy, platinum iridium alloy, gold or other suitable materials, and the developing spring 14 has good developing performance, so that the visibility of the pre-expansion guide wire under the X-ray is enhanced, and the success rate of the operation is increased. The stainless steel spring 15 here covers other parts of the distal core wire 11 than the part of the safety net 11.

In addition, the developing spring 14 or the stainless steel spring 15 is wound by a spring machine, for example, a spiral structure formed by winding metal wires side by a special spring machine, preferably, the winding diameter of the spring is set to be 0.001-0.007mm, the rotation speed of the spring machine for manufacturing the spring is about 1-10n/s, the pitch is 0.01-0.05mm, and the total length of the spring ring sheath is 10-30cm. In addition, 1-3 development marks may be provided at the proximal end of the coil sheath, said development marks being used to indicate, for example, the position of the coil sheath.

The second sheath 7 is at least disposed on the expansion portion 3 of the distal core wire 101, where the second sheath 7 and the distal core wire 101 may be connected by welding or hot melting, and if welding is performed, the second sheath 7 may be made of a suitable metal material, and if a hot-melt polymer sheath is performed, the second sheath 7 may be made of one of polyurethane, polylactic acid, nylon elastomer, and polyetheretherketone.

The safety net 11 is sleeved on the head end of the distal core wire 101 and is connected with the head end of the distal core wire 101, in another embodiment, both ends of the safety net 11 are connected and fixed with the head end of the distal core wire 101, and the safety net 11 is in a hollow cylinder shape made of metal wires through weaving or metal tube cutting.

Furthermore, since the distal core wire 101, the safety net 11 and the first sheath 12 are coaxially disposed and connected to each other, the distal core wire 101 can reach up to the head end of the pre-expanded guide wire, and the safety net 11 is sleeved on the head end, thus increasing the head end cross-sectional area of the pre-expanded guide wire. For example, the distal core wire 101 and the proximal core wire 102 may be prepared and connected, the safety net 11 may be sleeved, and the first sheath 12 may be installed, and then the three may be connected together, where the connection is one or more of resistance welding, soldering, ultrasonic welding, laser welding, adhesive bonding, and snap fitting. For example, if brazing is used, the welding temperature 200 is temperature 2.

Thus, as shown in fig. 6, 7, 8 and 9, the safety net 11 is arranged at the head end of the distal core wire 101, so that the cross-sectional area of the head end of the pre-expansion guide wire can be increased, the breaking force of the guide wire is improved, the diameter of the tip end of the distal core wire 101 is reduced, the head end of the pre-expansion guide wire is kept to be better flexible, the integral strength of the pre-expansion guide wire is enhanced, the shapes of the safety net 11 are overlapped in a crossed manner, the safety net 11 is enabled to be very flexible in the radial direction, and the breaking force in the axial direction is higher, so that the breaking and falling resistance of the head end of the pre-expansion guide wire can be enhanced, the safety of the head end is ensured, and the reliability is improved.

In addition, the type, material, number, size and location of the wires used in the safety net 11 may be customized according to the flexibility, safety, torque transmission, head end shaping ability and the like of the pre-expanded guide wire. In the process of manufacturing the safety net 11, the safety net 11 may be woven with wires to have different mesh densities (PPI) or different sizes according to different hardness requirements of the head end of the pre-expanded guide wire, and the safety net 11 may be connected to any position of the head end of the distal core wire 101 according to requirements, for example, the distal end of the safety net 11 and the head end of the distal core wire 101 may be welded together in parallel.

In another embodiment, the safety net 11 may be woven with a sparse distal portion and a gradually tighter intermediate and proximal portions.

Specifically, the number of wires of the safety net 11 is preferably 6 to 20, the diameter of the round wires is 0.0005 "-0.002", the size of the flat wires is 0.0005 "-0.002", and the longitudinal length of the safety net 11 thus manufactured is set to be 20 to 50mm. In one embodiment, the safety net 11 is formed by braiding 6 wires, each of which has a very small diameter, which may be about 1/4 of the diameter of the core wire 10 of the head end and is hollow cylindrical.

Considering that if the diameter of the head end of the core wire 10 is set to be very small if the safety net 11 is not provided at the head end of the pre-expanded guide wire but only the core wire 10, the head end of the pre-expanded guide wire can have good flexibility, but since the core wire 10 of the head end is very thin, it is easily broken, and a risk of breakage or falling off of the guide wire easily occurs at the time of clinical use. But when the diameter of the core wire 10 of the pre-expansion guide wire head end is increased, the strength of the pre-expansion guide wire can be enhanced, the risk of fracture or falling of the pre-expansion guide wire is avoided, but the hardness of the pre-expansion guide wire head end is increased, the head end softness cannot be maintained, and the risk of vascular perforation and the like caused by the hard guide wire head end in clinical use can be avoided.

The safety net 11 can fix the head end of the pre-expansion guide wire, the head end is easy to shape and has good shaping and retaining capacity, the pre-expansion guide wire has excellent torsion control performance, and the tail-swing effect is eliminated. The wires may be round wires or flat wires, for example, the number of heads and cross-sectional size of the wires of the safety net 11 may be increased when the head ends of the pre-expanded guide wires are required to be stiffer.

Further, since the core wire 10, the safety net 11 and the first sheath 12 at the head end of the pre-expanded guide wire are connected together, in consideration of circumferential rotation stability of the safety net 11, if the pre-expanded guide wire with the safety net 11 is placed in a twisted blood vessel, torque feedback at or near 1:1 will occur at the distal end of the pre-expanded guide wire when the proximal end of the pre-expanded guide wire is rotated, torque/moment loss of the guide wire is reduced, and a phenomenon of jumping or tail flicking occurring at the head end of the pre-expanded guide wire at the time of torque transmission is eliminated.

Here, the softness test is performed on the head end of the pre-expansion guide wire with the safety net 11, as shown in fig. 8, the pre-expansion guide wire is pushed by 10mm of the head end of the pre-expansion guide wire perpendicular to a balance, the force applied by the pre-expansion guide wire to be bent is the softness of the head end, and the harder the pre-expansion guide wire is the harder the larger the force value is, and vice versa. Fig. 9 is a graph showing the results of the softness and breaking force test of the head end of the pre-expansion guide wire with/without the safety net, and as can be seen from fig. 9, when the pre-expansion guide wire obtains a soft head end (0.6 g) without the safety net 11, the breaking force is small (4N), the risk of breaking or falling off of the guide wire easily occurs in clinical use, and when the high breaking force (7N) is obtained, the head end of the pre-expansion guide wire cannot simultaneously maintain softness (1.5 g), and the risk of vascular perforation and the like easily occurs in clinical use due to the hard head end of the pre-expansion guide wire; when the safety net 11 is arranged at the head end of the pre-expansion guide wire, the pre-expansion guide wire can obtain a soft head end (0.6 g, and the softness of the head end of the contrast is about 0.6 g) and can keep high breaking force (9N, and the breaking force of the contrast guide wire is about 7N); in this way, by extending the core wire 10 to the most distal end of the pre-expanded guide wire head end and connecting the safety net 11 and the first sheath 12 together, the torque/moment loss of the pre-expanded guide wire can be reduced, thereby achieving excellent torque controllability.

Further, the hydrophilic coating 13 is coated on a part or all of the surface of the first sheath 12, wherein the hydrophilic coating 13 is made of at least one of a polyvinylpyrrolidone coating, a polyethylene oxide coating, a transparent acrylate coating, or a polymethyl vinyl ether-maleic anhydride coating.

The coating method may be a spraying method or a painting method, and the coating is cured and formed by a certain method, so that the coating is not easy to fall off, for example, the appearance of the surface coating of the first sheath 12 may be observed after the hydrophilic coating 13 is coated. The hydrophilic coating 13 provides the pre-expanded guidewire with very good lubricity and tracking properties, thereby reducing the resistance of the pre-expanded guidewire to passage within the blood vessel, making the pre-expanded guidewire easy to push within the blood vessel.

According to the embodiment of the disclosure, the safety problem of the head end of the guide wire is solved, the head end of the guide wire is kept soft and simultaneously has higher breaking force, and meanwhile, excellent torsion control performance and deformation resistance are achieved, and particularly, the requirement of the head end softness, the higher breaking force and the excellent torsion control performance are achieved, wherein the head end is easy to shape for many times and has good shaping keeping force, and the hydrophilic coating on the surface enables the guide wire to have good lubricity and tracking performance, so that the comprehensive performance of the guide wire can be comprehensively improved.

The embodiment of the disclosure can pre-dilate the narrow part of the blood vessel based on the dilated part, is convenient for other interventional instruments to pass through the lesion part, and has simple preparation, easy realization and lower cost. Specifically, when the pre-expansion guide wire reaches a stenotic lesion, the head end thereof smoothly passes through the stenotic site due to the small diameter, the stenotic site is expanded due to the radial supporting effect based on the gradual increase of the diameter of the stenotic site, and the stenotic site of the pre-expansion guide wire is very smooth and soft in transition, without causing trauma to the blood vessel.

Moreover, although operations are depicted in a particular order, this should not be understood as requiring that such operations be performed in the particular order shown or in sequential order. In certain circumstances, multitasking and parallel processing may be advantageous. Likewise, while several specific implementation details are included in the above discussion, these should not be construed as limiting the scope of the present disclosure. Certain features that are described in the context of separate embodiments can also be implemented in combination in a single embodiment. Conversely, various features that are described in the context of a single embodiment can also be implemented in multiple embodiments separately or in any suitable subcombination.

Although the subject matter has been described in language specific to structural features and/or methodological acts, it is to be understood that the subject matter defined in the appended claims is not necessarily limited to the specific features or acts described above. Rather, the specific features and acts described above are example forms of implementing the claims.

While various embodiments of the present disclosure have been described in detail, the present disclosure is not limited to these specific embodiments, and various modifications and embodiments can be made by those skilled in the art on the basis of the concepts of the present disclosure, which modifications and modifications should fall within the scope of the claims of the present disclosure.

Claims (10)

1. The utility model provides a pre-expansion seal wire, its characterized in that includes the core silk, the diameter of core silk reduces gradually from the proximal end to the head end, the core silk includes distal end core silk and proximal end core silk that connects through resistance welding and/or bonding mode, distal end core silk includes at least the first part that is close to the head end and the second part that keeps away from the head end set up the expansion position in the second part, the diameter of expansion position is greater than the diameter of its both sides the outside of the distal end core silk of first part sets up first sheath, the outside of the distal end core silk of second part sets up the second sheath.

2. The pre-dilation guidewire of claim 1, wherein the diameter of the dilation site increases gradually from distal to proximal.

3. The pre-expanded guidewire of claim 1, wherein the second sheath is welded or hot-melt connected to the distal core wire, and wherein the second sheath is made of a metallic material when welded and a hot-melt polymer sheath when hot-melt.

4. The pre-expanded guidewire of claim 1, wherein a safety mesh is disposed between the distal core wire and the first sheath, the first sheath covering at least a portion of the safety mesh.

5. The pre-expanded guide wire according to claim 4, wherein the safety mesh is made by braiding wires, either round wire or flat wire, into different mesh densities or different sizes.

6. The pre-expanded guidewire of claim 1, wherein the first sheath is a spring coil sheath, a polymer sheath, or a combination thereof.

7. The pre-expanded guide wire according to claim 6, wherein when the first sheath is a spring coil sheath, the spring coil sheath is made by connecting a developing spring and a stainless steel spring, the developing spring covers a portion of the safety net, and the stainless steel spring covers other portions of the distal core wire than the safety net portion.

8. The pre-expanded guidewire of claim 1, wherein a hydrophilic coating is disposed on an outer surface of the first sheath.

9. The pre-expanded guide wire according to claim 1, wherein a metal tube is provided outside a portion where the distal core wire and the proximal core wire are connected, the metal tube being connected to the distal core wire and the proximal core wire by an adhesive.

10. The pre-expanded guidewire of claim 1, wherein the proximal core wire has a stiffness greater than a stiffness of the distal core wire.

Images