Guide wire

Abstract

The invention relates to a guidewire (1) having a core (2) extending from a proximal end to a distal end with a proximal section (3) adjacent to the proximal end and a distal section (4) adjacent to the distal end, the distal section (4) of the core (2) being wound around at least one coil (5). The coil (5) consists of at least two separate wires (6) which are arranged in parallel in a spiral form, and wherein the at least two wires (6) are connected to each other at a plurality of connection points (7) along the coil (5). The guidewire (1) according to the invention has a high degree of shape stability and improved rotational movement transmission performance.

Description

[0001] The invention relates to a medical guide wire, comprising a wire core extending from a proximal end to a distal end, wherein the proximal end section of the wire core is adjacent to the proximal end, the distal end section is adjacent to the distal end, and the distal end section of the wire core is wound with at least one coil.

[0002] In many medical interventions, such as revascularization, implantation of stents and flow deflectors, and intravascular examinations, guidewires are used to deliver other medical devices to the target location. In particular, in the vascular system, the guidewire guides the catheter or balloon catheter, which can be advanced over it once the guidewire is in place. With the help of or through the catheter, further medical devices can be delivered to the target location, such as thrombectomy devices, stents, flow deflectors, or implants for treating aneurysms. Microcatheters are particularly suitable.

[0003] As a result, the guidewire usually needs to be pushed to the distal end over a long distance, for example from the femoral artery to the intracranial vessels. Therefore, the length of the guidewire can reach about 1.30 meters to 3.50 meters. The problem that immediately arises is that the intracranial vessels are usually narrow and tortuous, so the guidewire must be flexible enough. In addition, it is also very important to avoid bending or even breaking of the guidewire during advancement ("anti-kinking"). Most importantly, the guidewire should be able to transmit torque during advancement, which is contrary to the design of the guidewire being too soft throughout. In addition, the distal end of the guidewire usually also has a special shape to facilitate entry into branch vessels. For example, the distal end can be bent laterally or proximally (such as 45° or 90°), or be J-shaped or crutch-shaped. Therefore, the distal end must be able to be shaped and able to maintain this shape (shape retention ability).

[0004] For the above reasons, the guidewire is usually composed of different segments, where the proximal segment is usually harder and less elastic to ensure the ability to propel and transmit torque, while the distal segment is designed to be very flexible so that it can follow the narrow blood vessels. To this end, the guidewire can be made of a different material at the proximal segment than at the distal segment, usually a metal or alloy. In addition, the outer diameter of the guidewire at the distal segment can be reduced.

[0005] Furthermore, the distal end of the guide wire is usually provided with a coil. Thus, the guide wire has an internal core and a coil arranged on the core. The coil is usually made of a radiopaque material so that the insertion process of the guide wire can be monitored by X-rays, in particular to ensure its correct positioning in the target area. Thus, the coil can be made of platinum or platinum-iridium wire.

[0006] However, as far as the prior art is concerned, the performance of the associated coils at the distal segment of the guidewire is generally unsatisfactory, especially in terms of torsion resistance. Typically, the attending physician needs to rotate the guidewire at a proximal position far outside the body to follow the path of the blood vessel. Therefore, the rotational movement must be transmitted over a long distance. In the area where the distal segment is equipped with a coil, the problem is that the coil attached to the vessel wall may be further loosened or compressed due to the rotation. As a result, the coil "stores" the applied rotational movement, which may result in a sudden release of the stored energy. This is undesirable, firstly because the physician cannot control this sudden movement, and secondly because it increases the risk of damaging the vessel wall.

[0007] Furthermore, while coils made of platinum or platinum alloys ensure adequate X-ray visibility, these metals are not ideal in other ways. In particular, they can make the distal segment of the guidewire too rigid, which is important for sufficient flexibility to accommodate the bends of the blood vessel.

[0008] In order to further improve the guidewire known in the prior art, the present invention provides an improved guidewire, which is provided with a core extending from a proximal end to a distal end, wherein the proximal section of the core is adjacent to the proximal end, and the distal section is adjacent to the distal end, and the distal section of the core is wound with at least one coil, wherein the coil is composed of at least two separate conductive wires, which extend adjacent to each other in a spiral shape and are connected at multiple connection points.

[0009] In the guidewire provided by the present invention, the coil is composed of at least two separate wires extending in a spiral shape side by side. Therefore, the wires are wound in parallel, and the coil is composed of at least two interlocking separate coils. In most cases, the coil is composed of two independent wires, but it can also be composed of 3 or more wires.

[0010] Furthermore, the wires forming the coil or the individual coils can be selectively connected to one another at specific connection points. This significantly increases the torsion resistance. In particular, the previously described disadvantageous effect of the above-mentioned storage of spring energy in the helical wire when transmitting a rotational movement can be eliminated.

[0011] U.S. Patent No. 10,639,456 discloses a guidewire with a coil in which the conductor has multiple connection points between turns of the coil along the coil. However, the present invention is different from this, and focuses on the connection points between turns of a single conductor. Through the present invention, the shape stability and the transmission performance of rotational motion and torque are further enhanced.

[0012] The core is a key wire that makes up the guidewire. Usually, its outer diameter is significantly larger than the other wires that make up the coil. In particular, the coil can be designed so that the diameter of the guidewire in the coil area is the same as or slightly larger than the diameter of the proximal section containing only the core. In other words, the diameter of the core is larger in the proximal section without the coil than in the distal section with the coil. However, the reduction in the core diameter can be compensated by adding coils, ensuring that the diameter of the entire guidewire remains approximately the same. The slightly larger diameter means that the core diameter in the proximal region may exceed by up to 30%, preferably up to 20%, and optimally up to 10%. In most cases, the core is solid, but the possibility of the core containing a cavity or lumen is not excluded. The coil can be firmly connected to the core by welding or other methods, and the welding points or other connection points are usually located at the proximal and distal ends of the coil.

[0013] The distal segment refers to the area of ​​the guidewire near the distal end, which is connected to the distal end in the proximal direction. The distal end itself can be part of the distal segment, but it is not necessary. The distal segment is shorter than the proximal segment, usually between 40 and 450 mm in length, 250 to 400 mm is particularly suitable, and the optimal length is about 300 mm. This not too short length helps to improve torsion resistance and prevent the coil from loosening or compressing. The distal end of the guidewire is preferably atraumatic in design, especially rounded, to prevent damage to the vessel wall during advancement.

[0014] The proximal segment refers to the area of ​​the guidewire adjacent to the proximal end of the guidewire in the distal direction. The proximal end itself can be part of the proximal segment, but it is not required. Typically, the proximal segment is significantly longer than the distal segment and occupies a considerable portion of the total length of the guidewire. If necessary, an intermediate segment can be added between the distal segment and the proximal segment.

[0015] The terms "proximal" and "distal" should be understood to mean that, when inserting a guidewire, the portion pointing toward the attending physician is defined as the proximal end, while the portion facing away from the physician is referred to as the distal end. Thus, the guidewire is typically passed through the vascular system in a distal direction. The term "axial" refers to the longitudinal axis of the device from the proximal end to the distal end, while the term "radial" refers to a plane perpendicular to the longitudinal axis.

[0016] One advantage is that the core has a smaller outer diameter in the distal section than in the proximal section. This design is consistent with the structure of conventional guidewires. By reducing the diameter of the distal section, the overall diameter of the guidewire does not increase significantly even when a coil is applied, and can even remain essentially unchanged. The transition between the proximal section or middle section of the core with a larger diameter and the distal section with a smaller diameter is preferably achieved continuously by a tapered transition section. Of course, the transition can also be achieved by one or more step structures.

[0017] The coil may be directly attached to the distal end section of the core, or a gap may be left between the coil and the distal end section of the core.

[0018] It is reasonable to design the connection points between the coil wires as welding points. The connection of different components of the guide wire by welding, even when different metals are involved, has been widely used and verified in the prior art. However, the formation of the connection points can also be achieved by other methods, such as brazing or bonding. In particular, the connection between the coil and the core can also be achieved by welding, which also opens up the possibility of other connection technologies, including brazing and bonding.

[0019] According to a first optimized embodiment, the connection points of the wires forming the coil are arranged at least partially in pairs, that is, each connection point has another connection point paired with it to form a connection point pair. An 180° offset between the connection point pairs has been proven to be effective. The 180° offset also includes a slight deviation from the ideal value of 180°, such as 5° or 10° higher or lower than the ideal value of 180°.

[0020] The offset between two connection points mentioned here refers to the fact that the cross section of the guidewire is basically circular in a plane orthogonal to the longitudinal axis. If this cross section is considered as a circle and divided into degrees, 360° is a complete circle, then an offset of 180° means that the connection points are in relative positions. Since the wire extends in a spiral shape, this naturally also means that there is a certain spacing between the connection points in the longitudinal direction.

[0021] Typically, the latter pair of connection points is slightly offset in space (in the circumferential direction) compared to the previous pair of connection points, for example, varying between 15° and 90°. Axially, the first connection point of an adjacent pair of connection points will move 15° to 90° relative to the first connection point of the previous pair of connection points, and the second connection point will also be offset by 15° to 90° accordingly. Along the entire length of the coil, the connection creates a torsional structure similar to the shape of the rifling in a gun barrel. This design ensures that the distal segment of the guidewire has high flexibility. In addition, the offset between the connection point pairs can also gradually increase from the proximal end to the distal end, resulting in a decrease in the density of connection points from the proximal end to the distal end, ultimately improving the overall flexibility.

[0022] According to a second optimized embodiment, the offset angle between the connection point pairs is 30 to 60°, preferably about 45°. The offset angle of the latter connection point pair relative to the previous connection point pair is 130° to 440°. In other words, the offset between each corresponding first connection point of two consecutive connection point pairs and between each corresponding second connection point of two consecutive connection point pairs is 130° to 440°.

[0023] According to a particularly optimized embodiment, the offset between the connection point pairs is dynamically changed, gradually increasing from the proximal end to the distal end. Therefore, the distal region of the coil has fewer connection points than the proximal region. For example, in the proximal region, the offset between the connection point pairs can be 130°, while in the distal region, the offset can reach 440°. Therefore, the distal region has a high degree of flexibility, while the proximal region has higher rigidity and better torque transmission performance. The transition of the connection point pairs from a small offset to a large offset can be continuous, such as gradually increasing from an offset of 130° to 440°, passing through many transition values ​​in between. However, it is also possible to provide a plurality of sequentially arranged regions in the longitudinal direction, each region having a different connection point offset, i.e., to achieve a step-by-step transition of the connection point density.

[0024] The aforementioned US Patent No. 10,639,456 describes a system in which the first and second connection points are opposite to each other, while the third and fourth connection points are offset by 90° compared to the first and second connection points. However, unlike the present invention, there are no connection points between the multiple wires in this system. Furthermore, the document does not show any variation in the offset, which is suitable for adjusting the properties of the guidewire, in particular the flexibility, according to the requirements.

[0025] Even if substantially opposing pairs of connection points are not formed, it may still be necessary to provide an offset between the connection points, for example between 15° and 270°, to positively influence the flexibility of the distal end segment of the guidewire.

[0026] By reducing the number of lead attachment points along the coil from the proximal end to the distal end, its flexibility can be adjusted. This makes the coil more rigid at the proximal end and more flexible at the distal end, which meets the mission requirement of increasing the flexibility of the lead, especially at its distal end.

[0027] By using wires made of different materials, the good properties of the materials can be combined with each other. Selecting different materials to manufacture the coil allows for an optimal adjustment of the wire properties and thus the properties of the distal end of the wire. In particular, a first wire material can be advantageously adjusted to one desired property of the coil, while a second wire material can be adjusted to another desired property.

[0028] It is advantageous to design at least one of the wires forming the coil to be visible to X-rays. To achieve this, a variety of metals and alloys can be used. For example, platinum or platinum alloys, such as platinum-iridium alloys, are options. Other options include platinum-tungsten alloys, platinum-nickel alloys, palladium, tantalum, gold and tungsten. X-ray visibility can also be achieved by gold plating the surface of the metal wire, the thickness of the gold plating can be 1 to 6 microns. Due to its higher strength, platinum-nickel alloys excel in plasticity and durability.

[0029] In order to enhance the elasticity of the distal end of the guidewire, it is recommended to make at least one wire constituting the coil into a superelastic or pseudoelastic alloy (shape memory alloy). In particular, nickel-titanium alloys (such as Nitinol) are very suitable as pseudoelastic alloys.

[0030] Another option is to manufacture at least one of the wires forming the coil from a cobalt-chromium alloy. Cobalt-chromium alloys have excellent properties in terms of torque transmission and handling properties, even at long distances. This is due to their high modulus of elasticity (Young's modulus) and high shear modulus. The high yield strength provides good resistance to bending ("kink resistance") and long-term bending. Cobalt-chromium-nickel alloys and cobalt-chromium-nickel-molybdenum alloys are particularly recommended. These alloys can be largely free of titanium, which enhances their properties. A corresponding alloy is known as 35N

[0031] With respect to the alloys involved in the present invention, it is hereby noted that mentioning a metal as one of the alloy components does not exclude the possibility that the alloy contains other components. For example, a cobalt-chromium alloy may contain other elements such as nickel or molybdenum in addition to cobalt and chromium. Similarly, a platinum-iridium alloy does not necessarily include only platinum and iridium. When metals are mentioned in the present invention, alloys are also included, and alloys may contain non-metals such as carbon or nitrogen in addition to metals. Possibilities and examples of superelastic / pseudoelastic alloys, X-ray visible alloys, cobalt-chromium alloys, etc., related to certain metals and alloys, all parts of this specification that mention these alloys are applicable, even if they are not explicitly mentioned in certain locations, unless there is a clear contrary statement in the text.

[0032] DFT (drawn filled tube) wire is widely used to construct coils. DFT wire has an inner layer made of a particular metal and an outer layer made of another metal, thus combining the properties of both metals. In particular, DFT wire can have an inner layer that is transparent to X-rays and an outer layer that is pseudo-elastic. Suitable materials include those mentioned above, especially platinum alloys for X-ray visibility and nickel-titanium alloys for pseudo-elasticity.

[0033] It is reasonable to make one of the wires wound side by side as an X-ray visible wire and the second wire as a pseudo elastic alloy or cobalt chromium alloy. For the second wire, a DFT wire can also be used, especially with an X-ray visible inner layer and a pseudo elastic or cobalt chromium outer sheath.

[0034] At least two wires made of a pseudoelastic alloy, in particular a nickel-titanium alloy, can be used to form a coil. To achieve X-ray visibility, a third wire made of an X-ray visible material, such as a platinum alloy, can be inserted between the other wires. The cross section of the third wire can be smaller than the other wires.

[0035] In order to adjust the lateral stiffness of the coil, the pitch of the coil or of the individual wires constituting the coil can be varied from the proximal end to the distal end. In particular, a smaller pitch can be present in the distal region of the coil compared to the proximal end. Accordingly, the windings at the distal end are more compact than at the proximal end. This can be achieved in sections, preferably with a uniform transition, i.e. the pitch decreases gradually from the proximal end to the distal end.

[0036] The wire windings forming the coil can be designed with certain gaps between the wires or with the wires directly connected. In this way, the flexibility of the coil and thus the flexibility of the guidewire can be specifically adjusted. Coils with larger gaps are generally more flexible than coils with smaller gaps, fewer gaps or no gaps.

[0037] The proximal section and the middle section of the core may be at least partially made of cobalt-chromium alloy. Since the proximal section together with the middle section may constitute the majority of the length of the guide wire, the guide wire can be well controlled and has sufficient bending resistance in this way. Of course, other materials such as stainless steel may also be used.

[0038] In the distal section, the core is preferably made of a superelastic alloy, in particular a nickel-titanium alloy. Typically, the distal section is significantly shorter than the proximal section, for example, having a length of about 40 to 450 mm, in particular 250 to 400 mm, and optimally about 300 mm. The use of a superelastic alloy in the distal section ensures a high degree of flexibility in this region, in particular in the area where flexibility is most important.

[0039] Therefore, it is reasonable to design the core with flexibility in different parts, with the distal section usually being more flexible than the proximal section. As mentioned, the flexibility can also be influenced by adjusting the material thickness or cross-section of the core, by being able to use different materials in different sections. In this case, the core usually has a larger cross-section at the proximal end than at the distal end. When different materials, especially metals or alloys, are used in different sections, a welded connection is usually made at the transition point.

[0040] In addition, it is particularly recommended to use DFT wires in the distal section of the wire core. A wire core with an X-ray visible inner structure and a superelastic sheath provides both critical X-ray visibility and flexibility in the distal section. In addition, a wire core with a sheath made of cobalt-chromium alloy and an X-ray visible inner structure can also be used.

[0041] According to a particularly optimized embodiment, the entire or at least the majority of the core consists of a wire having a superelastic inner structure and a sheath made of a cobalt-chromium alloy or a cobalt-chromium-nickel alloy. In the distal section, the sheath is completely or partially removed from the core. This process can be achieved in particular by a grinding process. The process can be carried out until only the superelastic inner structure of the wire remains in the distal section, but this is not absolutely necessary, since removing part of the sheath can already improve flexibility. The main advantage of this method is that it does not require incompatible welding of different sections of the core.

[0042] An advantage of a core composed of a superelastic or pseudoelastic alloy (e.g., Nitinol) is that it can be shaped by appropriate heat treatment. The excellent superelastic properties ensure that its shape is maintained (shape retention capability). This is particularly important because the distal end of the guidewire is often required to have an arc or bend to facilitate exploration of the path of the vessel and location of branch vessels.

[0043] It is also possible to make the wire or wires forming the coil into a coil, i.e. twist them into a coil before winding them into a helical shape. In this way, a structure similar to a coil around a coil is obtained, or a double-layer coil, i.e. a secondary coil is formed from a primary coil. In such a coil (i.e. a secondary coil), the primary coils formed from the twisted wires of the wires can be placed side by side. However, it is also possible to twist only part or a single wire into the coil shape before forming the coil.

[0044] In the distal section of the core, a plurality of coils may be radially stacked. In other words, one coil may be arranged outside another coil, and the overlap may be complete or partial. For example, from US Pat. No. 8,480,598 B2, stacked helical coils are known. According to the invention, at least one coil is formed from at least two separate conductors. The overlap of the individual coils need not be completely identical, and one or more coils may be shorter than the others or only partially overlap.

[0045] When multiple coils are stacked together, it is best to wind them in opposite directions, once as a left-handed helix and once as a right-handed helix, or alternately. This arrangement can improve torque transfer because the opposite rotation of the coils can balance the difference in rotation direction.

[0046] The at least two wires forming the coil do not always have to be arranged in a spiral parallel to each other over the entire coil length, but should be arranged in this way over most of the length, preferably accounting for at least 70% of the total length of the coil, more preferably more than 80%, and more preferably more than 90%. However, the most ideal solution is to have the wires forming the coil arranged in a spiral parallel to each other for 100% of the total length.

[0047] The distal end of the guidewire may have a bend or curvature. For example, the distal end of the guidewire may present a bend ranging from 45° to 180°, such as 90° or 135°. Thus, the distal end of the guidewire may form a "J" shape or a crutch shape. A major advantage of this design is that it allows for easier exploration and passage through narrow vessels. First, the curved tip can be adjusted by rotation to a position that better adapts to the curve of the vessel. Second, a guidewire with a distal bend or curvature is more non-invasive, i.e., the risk of damaging the vessel wall is reduced. Maintaining the shape of the distal end of the guidewire helps to better perform the guidewire task. The coil is completely or partially located in the curved area or in a proximal position.

[0048] In most cases, the cross section of the wire and the core forming the coil is circular. However, in principle, other shapes, in particular shapes with an elliptical cross section, can also be used.

[0049] The properties of the guide wire or its individual components can be influenced by processes known in the prior art, such as cold working, heat treatment, tempering or recrystallization annealing.

[0050] It is reasonable to apply a polymer sheath on the outer surface of the guide wire. In addition to or instead of the polymer sheath, a hydrophilic coating can also be applied. The polymer sheath can especially adopt PTFE (polytetrafluoroethylene) or other fluoropolymers. Other materials that can be used as polymer sheaths include polyamide, polyurethane, polyvinyl chloride, polyester, polystyrene, polyimide, polycarbonate, polyolefin (such as polypropylene or polyethylene) or silicone. The polymer sheath and / or hydrophilic coating do not necessarily need to cover the full length of the guide wire, and local sheath or coating treatment is also possible. For example, a polymer sheath can be applied to the proximal section, and a hydrophilic coating can be applied to the distal end to improve the sliding performance of the guide wire. The hydrophilic coating can extend beyond the distal section, wrap the coil, and cover a length of about 30 to 40 cm. As a hydrophilic coating, polyvinyl pyrrolidone, cellulose-based polymers or polyvinyl alcohol can be used.

[0051] The guidewire of the present invention is particularly suitable for the neurovascular field, but can also be used in the cardiovascular and peripheral fields. The use of the guidewire in intracranial and coronary vessels is particularly important because in these cases, on the one hand, it is necessary to pass through narrow blood vessels, and on the other hand, it is necessary to advance the guidewire over a long distance.

[0052] The diameter of the guidewire is typically between 0.2 and 0.5 mm, but does not need to be constant throughout its length.

[0053] The guidewire of the present invention can be used in conjunction with an OTW (Over The Wire) catheter and an Rx (Rapid Exchange) catheter. In an OTW catheter, the guidewire runs through the entire lumen of the catheter. In an Rx catheter, the guidewire only passes through the distal segment of the catheter, which is usually about 20 to 40 cm long. Therefore, the catheter has an outlet, also called a port, at the proximal end of the distal segment through which the guidewire passes and leaves the catheter lumen. The OTW and Rx systems are well-recognized in the field of balloon catheters and the like.

[0054] At the proximal end, the guidewire may be equipped with a handle to facilitate easier manipulation of the guidewire by the attending physician.

[0055] The present invention not only relates to the guidewire itself, but also includes a method for using the guidewire and a combination of the guidewire and other medical devices.

[0056] All descriptions of features of the invention apply to all embodiments unless otherwise stated.

[0057] The present invention will be described in detail by the embodiments shown in the drawings. It is worth noting that the drawings are only preferred embodiments of the present invention and the invention is not limited thereto. In general, the present invention includes any combination of technical features related to the invention listed in the claims or described in the description, as long as it is technically advantageous.

[0058] The diagram is as follows:

[0059] Figure 1 is a side view of a guide wire according to a first embodiment of the present invention;

[0060] Figure 2 is a side view of a guide wire according to a second embodiment of the present invention;

[0061] Figure 3 is a side view of a partial coil of a guide wire according to another embodiment of the present invention;

[0062] Figure 4 for Figure 3 An oblique view of the portion of the coil shown;

[0063] Figure 5 is a side view of a partial coil of a guide wire according to another embodiment of the present invention;

[0064] Figure 6 for Figure 5 An oblique view of the portion of the coil shown.

[0065] Figure 1The figure is a side view of a guide wire 1 according to the present invention, wherein the distal section 4 is connected to the proximal section 3 along the longitudinal axis 9. The length of the proximal section 3 (not fully shown) significantly exceeds the length of the distal section 4. The guide wire 1 comprises a core 2, the diameter of which is reduced at the distal section 4. At the distal section of the core 2, a coil 5 is fixed so that the total diameter of the guide wire 1 at the distal section 4 is substantially the same as that of the proximal section 3. The proximal section 3 of the core 2 is made of a cobalt-chromium-nickel-molybdenum alloy, while the distal section 4 is made of a superelastic nickel-titanium alloy. The distal section 4 of the guide wire 1 is covered with a hydrophilic coating 11 on the outside.

[0066] The coil 5 is composed of two helically adjacent and parallel wires 6, in this embodiment, wires 6 of different diameters are used. The thicker wire 6 is made of nickel-titanium alloy, while the thinner wire 6 is a platinum wire, which ensures that the distal section 4 has good X-ray visibility.

[0067] Figure 2 It is a variant of the guide wire 1 of the present invention, and its basic structure is the same as Figure 1 The coil 5 here consists of two wires 6 of the same diameter, one of which is made of nickel-titanium alloy, and the other is a DFT wire whose interior is made of platinum or platinum alloy with X-ray visibility and is wrapped with a pseudo-elastic shell of nickel-titanium alloy. In addition, a coil 8 is provided inside the coil 5, which extends only to a part of the length of the coil 5 and is made of platinum.

[0068] Figure 3 It is a part of the coil 5, i.e. the distal part. The wires 6 are wound side by side in a spiral shape and connected to each other at the connection point 7. The offset between each connection point pair 10 is 45°. The next connection point pair 10 is offset by 440° relative to the previous connection point pair. Since the offset between the two connection points 7 in this connection point pair 10 is also 45°, this means that the offset between the first connection points 7 of two consecutive connection point pairs 10 is also 440°. The same applies to the offset between the second connection points 7 of two consecutive connection point pairs 10. The connection point 7 is usually a welding point.

[0069] Generally speaking, in this embodiment, the spacing between the connection point pairs 10 is large, that is, the total number of connection points 7 is relatively small. This makes the coil 5 highly flexible, which is particularly desirable at the distal end.

[0070] Figure 4 for Figure 3 Oblique view of the middle coil. It can be seen that the distribution of the connection points 7 is relatively loose.

[0071] Figure 5It is another part of the coil 5, which is more likely to appear in the proximal region of the coil 5. Here, the offset angle between the connection points 7 of the connection point pair 10 is 45°, while the offset angle between the connection point pairs 10 is 130°, which is significantly smaller. Therefore, the connection points 7 are arranged more densely, which results in lower flexibility, but higher rigidity and better torque transmission performance.

[0072] Figure 6 for Figure 5 An oblique view of the coil in FIG. It can be seen that the connection points 7 are relatively densely distributed.

Claims

1. A guide wire, comprising a wire core (2) extending from a proximal end to a distal end, a proximal end segment (3) adjacent to the proximal end, and a distal end segment (4) adjacent to the distal end, wherein the distal end segment (4) of the wire core (2) is wound by at least one coil (5), It is characterized in that The coil (5) is formed by at least two separate wires (6), which are arranged helically adjacent to each other, and wherein at least two of the wires (6) are connected to each other at a plurality of connection points (7) along the coil (5).

2. A guide wire according to claim 1, characterized in that: At least two of the conductive wires (6) are made of at least two different materials.

3. A guide wire according to claim 1 or 2, characterized in that: The outer diameter of the distal end section (4) of the wire core (2) is smaller than the outer diameter of the proximal end section (3).

4. A guide wire according to any one of claims 1 to 3, characterized in that: The connection point (7) is a welding point.

5. A guide wire according to any one of claims 1 to 4, characterized in that: The number of the connection points (7) decreases gradually from the proximal end to the distal end along the coil (5).

6. A guide wire according to any one of claims 1 to 5, characterized in that: The connection points (7) are at least partially arranged in pairs.

7. A guide wire according to claim 6, characterized in that: The offset between the two connection points (7) of a connection point pair (10) is approximately 180°.

8. A guide wire according to claim 7, characterized in that: The offset between the first connection points (7) of two adjacent connection point pairs (10) is 15° to 90°, and the first connection point (7) is the connection point (7) closer to the proximal end in the connection point pair (10).

9. A guide wire according to claim 6, characterized in that: The offset between the connection points (7) in a connection point pair (10) is 30° to 60°, preferably about 45°.

10. A guide wire according to claim 9, characterized in that: The offset between each first connection point (7) of two consecutive connection point pairs (10) is 130° to 440°, and each first connection point (7) is a connection point (7) closer to the proximal end in the connection point pair (10).

11. A guide wire according to any one of claims 6 to 10, characterized in that: The offset between each first connection point (7) of two consecutive connection point pairs (10) gradually increases from the proximal end to the distal end.

12. A guide wire according to any one of claims 1 to 11, characterized in that: At least one of the wires (6) constituting the coil (5) is visible to X-rays.

13. A guide wire according to any one of claims 1 to 12, characterized in that: At least one wire (6) constituting the coil (5) is made of a superelastic alloy or a cobalt-chromium alloy.

14. A guide wire according to any one of claims 1 to 13, characterized in that: The pitch of the coil (5) gradually decreases from the proximal end to the distal end.

15. A guide wire according to any one of claims 1 to 14, characterized in that: The wire core (2) in the proximal section (3) is at least partially composed of a cobalt-chromium alloy.

16. A guide wire according to any one of claims 1 to 15, characterized in that: The wire core (2) in the distal section (4) is at least partially composed of a superelastic alloy.

17. The guide wire according to claim 16, characterized in that The distal section (4) of the core (2) has a radiopaque interior and a sheath made of a superelastic alloy.

18. A guide wire according to any one of claims 1 to 14, characterized in that: The wire core (2) consists of a superelastic inner structure and a sheath of cobalt-chromium or cobalt-chromium-nickel alloy, which is completely or partially removed at the distal end section (4) of the wire core (2).

19. A guide wire according to any one of claims 1 to 18, characterized in that: At least some of the wires (6) forming the coil (5) are twisted together.

20. A guide wire according to any one of claims 1 to 19, characterized in that: The distal end section (4) of the core (2) is wound with a plurality of coils (5, 8) which are arranged in a radially overlapping manner.

21. A guide wire according to any one of claims 1 to 20, characterized in that: At least two conductors (6) forming the coil (5) are laid out helically side by side over at least 70% of the total length, preferably at least 80%, further preferably at least 90%, particularly preferably 100% of the length.

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