Guide wire insertion method

Abstract

To provide a guide wire insertion method for inserting a guide wire into a blood vessel having a main vessel and a collateral branching off from the main vessel.SOLUTION: A guide wire insertion method includes: providing a guide wire having a knuckle progress suppression structure; inserting the guide wire into a main vessel of a blood vessel of a patient and pushing the tip of the guide wire toward an affected part; after a knuckle occurred at the tip portion of the guide wire due to catching of the tip of the guide wire onto a collateral of the blood vessel, suppressing the progress of the knuckle by using the knuckle progress suppression structure; removing the tip of the guide wire from the collateral, and pushing the tip portion toward the affected part in the main vessel while maintaining the knuckle.SELECTED DRAWING: Figure 3

Description

Technical Field

[0001] The present disclosure relates to a method of inserting a guide wire into a blood vessel in vascular treatment.

Background Art

[0002] A guide wire is known as a medical device for guiding a catheter-like medical instrument inserted into a tubular organ of the human body, such as a blood vessel or a digestive organ, to a target site. For example, there is percutaneous coronary intervention (PCI) performed for the treatment of ischemic heart disease in the coronary arteries of the heart, such as angina pectoris and myocardial infarction. In percutaneous coronary intervention, a guide wire is passed through a blood vessel to pass through a stenosis (affected part) that causes the disease, and a procedure is performed to deliver a balloon catheter or a stent to the stenosis using the guide wire.

[0003] Conventionally, in the procedure of PCI, the guide wire is inserted by selecting a branched blood vessel branched from the main blood vessel. For this purpose, it has been common to use a guide wire having a shaped tip and operate the tip to guide it to the affected part. For example, Japanese Patent Laid-Open No. 59-067968 discloses performing vascular treatment using a guide wire having a shaped tip.

Summary of the Invention

[0004] However, in practice, there are many cases where it is not necessary to select a branched blood vessel as in main vessel treatment. When trying to push the guide wire tip through the blood vessel by operating the tip of the guide wire in such main vessel treatment, there are problems such that the tip of the guide wire inadvertently strays into fine blood vessels, or the tip contacts the blood vessel wall and dissociation or perforation occurs. In addition to such problems, there is also a concern about an increase in the load on the blood vessel wall due to the tip of the guide wire contacting the blood vessel wall at a point.

[0005] The present disclosure has been made in view of the above circumstances, and an object thereof is to provide a method for inserting a guide wire in which the tip of the guide wire is less likely to cause entry into a microvessel or dissociation / perforation of the vessel wall, and the load on the vessel wall is suppressed.

[0006] To achieve the above object, the present disclosure provides a guide wire insertion method for inserting a guide wire into a blood vessel having a main tube and a side branch branching from the main tube, the method comprising: preparing a guide wire having a knuckle progression suppression structure; inserting the guide wire into the main tube of the patient's blood vessel and pushing the tip of the guide wire toward the affected part; suppressing the progression of the knuckle using the knuckle progression suppression structure after a knuckle has occurred at the tip of the guide wire due to the tip of the guide wire being caught by the side branch of the blood vessel; and removing the tip of the guide wire from the side branch and pushing the tip forward while maintaining the knuckle toward the affected part within the main tube (Disclosure 1).

Brief Description of the Drawings

[0007]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Mode for Carrying Out the Invention

[0008] Hereinafter, a guide wire insertion method according to an embodiment of the present disclosure will be described. The present disclosure is not limited only to the embodiments described below, and the described embodiments are merely examples for explaining the technical features of the present disclosure. The shapes and dimensions shown in each drawing are merely shown to facilitate the understanding of the content of the present disclosure and do not correctly reflect the actual shapes and dimensions.

[0009] <Structure of the guide wire> Since the guide wire insertion method of the present disclosure uses a guide wire having a knuckle progression suppression structure, first, the structure of the guide wire 10 used in the guide wire insertion method will be described based on the drawings. The guide wire 10 is suitable for the treatment of ischemic heart disease in the coronary arteries of the heart and is a workhorse guide wire for guiding a catheter, stent, etc. for percutaneous coronary intervention (PCI) to a coronary artery stenosis site. The distal end side of the guide wire 10 is the side inserted into the body, and the proximal end side of the guide wire 10 is the side operated by a technician such as a doctor. In the guide wire 10, a knuckle progression suppression structure (details will be described later) is realized by the surface of the first region 10a located on the distal end side of the guide wire 10 being less slippery than the surface of the second region 10b located on the proximal end side of the first region.

[0010] In this specification, the "distal end side" means a direction along the axial direction of the guide wire and is the direction in which the guide wire advances toward the target site. The "proximal end side" means a direction along the axial direction of the guide wire and is the direction opposite to the distal end side. The "tip" indicates the end on the distal end side of any member or part, and the "base end" indicates the end on the proximal end side of any member or part. The "tip portion" refers to a portion of any member or part that includes the tip and extends from the tip toward the proximal end side to the middle of the member or the like. The "base end portion" refers to a portion of any member or part that includes the base end and extends from the base end toward the distal end side to the middle of the member or the like. In FIG. 1, the left side shown in the figure is the "distal end side" inserted into the body, and the right side shown in the figure is the "proximal end side" operated by the technician.

[0011] When inserting a guide wire into a blood vessel or the like, in order to improve the passability of a lesion in the blood vessel or the like, or to prevent damage to the blood vessel wall or the like and unintentional entry into unintended collateral branches, the tip side of the guide wire may be intentionally bent into a U shape within the blood vessel. This state is called a knuckle (or prolapse). If the knuckle further progresses as the guide wire is pushed forward after the formation of the knuckle, the reaction force for the guide wire to return straight increases, which may cause problems such as damage to the blood vessel wall. A structure that suppresses excessive progression of the knuckle by changing the rigidity or surface characteristics of the tip side of the guide wire is called a knuckle progression suppression structure.

[0012] FIG. 1 is an explanatory view showing the structure of a guide wire 10. The guide wire 10 includes a long core shaft 1 and a cylindrical body 2 provided outside the core shaft 1. A tip chip 3 that joins the core shaft 1 and the cylindrical body 2 is provided at the tip of the guide wire 10. A fixing portion 4 that fixes the core shaft 1 and the cylindrical body 2 is provided at the proximal end of the cylindrical body 2. An inner cylindrical body 8 is disposed inside the cylindrical body 2 along the outer circumference of the core shaft 1.

[0013] The core shaft 1 is a long member that serves as the axis of the guide wire 10. As shown in FIG. 1, the core shaft 1 has a reduced-diameter portion 11 on the tip side and a large-diameter portion 13 on the proximal end side. The core shaft 1 has a tapered portion 12 whose outer diameter decreases from the proximal end side toward the tip side between the reduced-diameter portion 11 and the large-diameter portion 13. The core shaft 1 can be formed of a material such as a stainless alloy (SUS302, SUS304, SUS316, etc.), a superelastic alloy such as a Ni-Ti alloy, a piano wire, a nickel-chromium-based alloy, a cobalt alloy, or tungsten. The material of the core shaft 1 is not limited to this, and the core shaft 1 may be formed of other known materials as long as it can prevent self-cutting of the core shaft 1 itself and rotate the tip portion.

[0014] The small-diameter portion 11 has a cylindrical shape with a constant outer diameter from the tip to the base end. Alternatively, the small-diameter portion 11 may have a flat cross-sectional shape formed by pressing. The large-diameter portion 13 has a cylindrical shape with a constant outer diameter from the tip to the base end. The tapered portion 12 has a frustum shape in which the outer diameter gradually increases from the tip to the base end.

[0015] The cylindrical body 2 is wound around the core shaft 1 so as to cover a part of the outer circumferences of the small-diameter portion 11, the tapered portion 12, and the large-diameter portion 13 of the core shaft 1.

[0016] The cylindrical body 2 may be a single coil formed by spirally winding a single wire of a circular cross-section into a cylindrical shape, or may be a hollow twisted wire coil formed by forming a twisted wire by twisting a plurality of wires into a cylindrical shape. The cylindrical body 2 may be configured by combining a single coil and a hollow twisted wire coil. The cylindrical body 2 can be formed of, for example, a stainless alloy (such as SUS302, SUS304, SUS316, etc.), a superelastic alloy such as a Ni-Ti alloy, a piano wire, a radiation-permeable alloy such as a nickel-chromium alloy or a cobalt alloy, a radiation-impermeable alloy such as gold, platinum, tungsten, or an alloy containing these elements (for example, a platinum-nickel alloy). The material of the cylindrical body 2 is not limited to this, and may be formed of a known material other than the above. In the present embodiment, the tip side of the cylindrical body 2 is formed of a radiation-impermeable alloy, and the base end side is formed of a stainless alloy, and its outer diameter is configured to be substantially constant from the tip to the base end.

[0017] At the tip of the guide wire 10, that is, at the tip of the core shaft 1, a tip chip 3 for joining the core shaft 1 and the cylindrical body 2 is formed. The tip chip 3 is formed of a metal solder such as silver solder, gold solder, zinc, Sn-Ag alloy, Au-Sn alloy, etc., and the tip of the core shaft 1 and the tip of the cylindrical body 2 are fixed by this metal solder. The tip chip 3 may be formed of an adhesive such as an epoxy-based adhesive, and the tip of the core shaft 1 and the tip of the cylindrical body 2 may be fixed by the adhesive.

[0018] At the proximal end of the cylindrical body 2, a fixing portion 4 for fixing the core shaft 1 and the cylindrical body 2 is formed. The fixing portion 4 is formed by a metal solder such as silver solder, gold solder, zinc, Sn-Ag alloy, Au-Sn alloy, etc. By this metal solder, the proximal end of the cylindrical body 2 is fixed to the large-diameter portion 13 of the core shaft 1. It is also possible to form the fixing portion 4 with an adhesive such as an epoxy-based adhesive and fix the large-diameter portion 13 of the core shaft 1 and the proximal end of the cylindrical body 2 with the adhesive.

[0019] Inside the cylindrical body 2, two joining portions 5a and 5b for joining the tapered portion 12 of the core shaft 1 and the cylindrical body 2 are formed. The joining portions 5a and 5b are formed by a metal solder such as silver solder, gold solder, zinc, Sn-Ag alloy, Au-Sn alloy, etc. By this metal solder, the tapered portion 12 of the core shaft 1 and the cylindrical body 2 are fixed. It is also possible to form the joining portions 5a and 5b with an adhesive such as an epoxy-based adhesive and fix the tapered portion 12 of the core shaft 1 and the cylindrical body 2 with the adhesive.

[0020] The inner cylindrical body 8 is shorter in length than the cylindrical body 2 and is wound around the outer side of the core shaft 1 so as to cover the outer circumference from the small-diameter portion 11 to a part of the tapered portion 12 of the core shaft 1. As a result, only at the tip of the guide wire 10, the cylindrical body 2 and the inner cylindrical body 8 overlap on the outer side of the core shaft 1.

[0021] The tip of the inner cylindrical body 8 is fixed to the tip chip 3, and the proximal end of the inner cylindrical body 8 is fixed to the tapered portion 12 of the core shaft 1 by a joining portion 5c. The joining portion 5c may be formed by a metal solder such as silver solder, gold solder, zinc, Sn-Ag alloy, Au-Sn alloy, etc., or may be formed by an adhesive such as an epoxy-based adhesive.

[0022] The inner cylindrical body 8 may be a single coil formed by spirally winding a single wire with a circular cross-section into a cylindrical shape, or may be a hollow twisted wire coil formed by twisting a plurality of wires into a cylindrical shape. The inner cylindrical body 8 may be configured by combining a single coil and a hollow twisted wire coil. The inner cylindrical body 8 is made of, for example, a stainless alloy (such as SUS302, SUS304, SUS316, etc.), a superelastic alloy such as a Ni-Ti alloy, a piano wire, a radiation-permeable alloy such as a nickel-chromium alloy, a cobalt alloy, a radiation-impermeable alloy such as gold, platinum, tungsten, an alloy containing these elements (for example, a platinum-nickel alloy), etc. The material of the inner cylindrical body 8 is not limited to this, and may be formed of a known material other than the above. In this modification, the inner cylindrical body 8 is formed as a single member entirely of the same material, and its outer diameter is configured to be constant from the tip to the base end.

[0023] The outer peripheral surface of the cylindrical body 2 is partitioned into a first surface region 21 located on the tip side and a second surface region 22 located on the base end side of the first surface region 21, and the surface characteristics of the first surface region 21 are different from those of the second surface region 22. The cylindrical body 2 having the first surface region 21 and the second surface region 22 on its outer peripheral surface is provided outside the core shaft 1. Thereby, the guide wire 10 includes a first region 10a having the first surface characteristics, and further includes a second region 10b having the second surface characteristics and located on the base end side of the first region 10a. The first region 10a of the guide wire 10 is a region including the tip of the guide wire 10.

[0024] The first surface characteristic of the first region 10a is that when a friction and wear test is performed on the first region 10a, the first region 10a has a first friction resistance value R1. The second surface characteristic of the second region 10b is that when a friction and wear test is performed on the second region 10b under the same conditions as those for the first region 10a, the second region 10b has a second friction resistance value R2. In the guide wire 10, the first friction resistance value R1 is greater than the second friction resistance value R2. By controlling the surface characteristics of the first region 10a and the second region 10b, a high-friction region can be provided on the tip side of the guide wire 10 and a low-friction region can be provided on the base end side. Thereby, the progression of the knuckle can be controlled. That is, in the guide wire 10, a knuckle progression suppression structure is realized by providing a high-friction region on the tip side (the first region 10a) of the guide wire 10 and a low-friction region on the base end side (the second region 10b).

[0025] In the guide wire 10, the first surface characteristic of the first region 10a (the first surface region 21) may be that the surface friction coefficient of the first region 10a is a first friction coefficient μ1. The second surface characteristic of the second region 10b (the second surface region 22) may be that the surface friction coefficient of the second region 10b is a second friction coefficient μ2. In this case, in the guide wire 10, the first friction coefficient μ1 is greater than the second friction coefficient μ2. By controlling the surface characteristics of the first region 10a and the second region 10b in this way, a high-friction region can be provided on the tip side of the guide wire 10 and a low-friction region can be provided on the base end side.

[0026] The relationship between the above-described first friction coefficient μ1 and the above-described second friction coefficient μ2 may be adjusted, for example, by forming coating layers of different materials on the respective regions, or may be adjusted by forming a coating layer only on one of the regions. The above-described relationship may be adjusted by performing different surface processing treatments on the respective regions. The above-described relationship may be adjusted by forming coating layers of the same material on the respective regions and then performing surface processing treatment only on the coating layer formed on one of the regions.

[0027] In this embodiment, a first coating layer 6 is formed on the surface of the first region 10a of the guide wire 10, and a second coating layer 7 is formed on the second region 10b of the guide wire 10. The materials of the first coating layer 6 and the second coating layer 7 are selected such that the surface friction coefficient μ1 of the first coating layer 6 is greater than the surface friction coefficient μ2 of the second coating layer 7.

[0028] The first coating layer 6 is a silicone coating layer, and can be formed, for example, by a known coating formation method such as applying a medical-grade silicone solution to the tip side of the cylindrical body 2 and the surface of the tip chip 3. That is, in this embodiment, the first surface characteristic of the first region 10a is that the surface of the first region 10a is hydrophobic. In other words, it can be said that a silicone coating layer is formed as the first coating layer 6 on the surface of the first region 10a.

[0029] The second coating layer 7 is a hydrophilic coating layer. The hydrophilic coating layer can be formed by a known coating formation method. For example, solutions of nonionic hydrophilic polymers such as polyvinyl alcohol, polyvinyl pyrrolidone, polyethylene glycol, polyacrylamide, polymethylacrylamide, poly(2-hydroxyethyl methacrylate), poly(N-hydroxyethyl acrylamide), anionic hydrophilic polymers such as polyacrylic acid, polymethacrylic acid, polymaleic acid, carboxymethyl cellulose, hyaluronic acid, poly(2-acrylamide-2-methylpropanesulfonic acid), and cationic hydrophilic polymers such as polyethyleneimine, polyallylamine, and polyvinylamine are applied to the base end side of the cylindrical body 2, the fixing portion 4, and the surface of the base end side of the large-diameter portion 13 of the core shaft 1. That is, in this embodiment, the second surface characteristic of the second region 10b is that the surface of the second region 10b is hydrophilic. In other words, it can be said that a hydrophilic coating layer is formed as the second coating layer 7 on the surface of the second region 10b.

[0030] In the guide wire 10, the surface of the first region 10a located on the distal end side of the guide wire 10 is less slippery than the surface of the second region 10b located on the proximal end side of the first region 10a, realizing a knuckle progression suppression structure. In such a guide wire 10, a first region 10a, which is a high-friction region, is provided on the distal end side, and a second region 10b, which is a low-friction region, is provided on the proximal end side. As a result, the guide wire 10 is easily bent up to the vicinity of the boundary between the first region 10a and the second region 10b, and the progression of the knuckle toward the proximal end side beyond the vicinity of the boundary can be suppressed.

[0031] <Modification example of the structure of the guide wire> A modification example of the structure of the guide wire used in the guide wire insertion method of the present disclosure will be described. In the above-described guide wire 10, the knuckle progression suppression structure was realized by the surface of the first region 10a located on the distal end side of the guide wire 10 being less slippery than the surface of the second region 10b located on the proximal end side of the first region 10a. In the guide wire 10A of the modification example described below, the knuckle progression suppression structure is realized by the rigidity of the first region 10Aa located on the distal end side of the guide wire being different from the rigidity of the second region 10Ab located on the proximal end side of the first region 10Aa.

[0032] FIG. 2 is an explanatory diagram showing the structure of the guide wire 10A according to the present embodiment. The guide wire 10A includes a long core shaft 1A and a cylindrical body 2A provided outside the core shaft 1A. A tip chip 3A that joins the core shaft 1A and the cylindrical body 2A is provided at the tip of the guide wire 10A, and a fixing portion 4A that fixes the core shaft 1A and the cylindrical body 2A is provided at the proximal end of the cylindrical body 2A.

[0033] The core shaft 1A is an elongated member that serves as the axis of the guide wire 10A. As shown in FIG. 2, the core shaft 1A has a reduced-diameter portion 11A on the tip side and a large-diameter portion 13A on the base end side, and has a tapered portion 12A whose outer diameter decreases from the base end side toward the tip side between the reduced-diameter portion 11A and the large-diameter portion 13A. The core shaft 1A can be formed of materials such as, for example, stainless alloys (SUS302, SUS304, SUS316, etc.), superelastic alloys such as Ni-Ti alloys, piano wire, nickel-chromium alloys, cobalt alloys, tungsten, and the like. The core shaft 1A is not limited to this, and may be formed of other known materials as long as it can prevent the core shaft 1A itself from being cut and can rotate the tip portion.

[0034] Due to the difference in their diameters, the reduced-diameter portion 11A, the tapered portion 12A, and the large-diameter portion 13A of the core shaft 1A have different rigidities from each other. The reduced-diameter portion 11A has a cylindrical shape with a constant outer diameter from the tip to the base end, and its second moment of area is constant throughout the reduced-diameter portion 11A. The large-diameter portion 13A also has a cylindrical shape with a constant outer diameter from the tip to the base end, and its second moment of area is constant throughout the large-diameter portion 13A. The tapered portion 12A has a frustum shape in which the outer diameter gradually increases from the tip toward the base end, and its second moment of area also gradually increases from the tip toward the base end. Since the reduced-diameter portion 11A of the core shaft 1A serves as the axis of the guide wire 10A, the rigidity of the guide wire 10A is configured to change in the axial direction.

[0035] The cylindrical body 2A is wound around the core shaft 1A so as to cover a part of the outer circumferences of the small-diameter portion 11A, the tapered portion 12A, and the large-diameter portion 13A of the core shaft 1A. The cylindrical body 2A may be a single coil formed by spirally winding a single wire of a circular cross-section into a cylindrical shape, or may be a hollow twisted wire coil formed by twisting a plurality of wires into a cylindrical shape. The cylindrical body 2A may be configured by combining a single coil and a hollow twisted wire coil. The cylindrical body 2A can be formed of, for example, stainless alloys (such as SUS302, SUS304, SUS316, etc.), superelastic alloys such as Ni-Ti alloys, piano wires, nickel-chromium-based alloys, radiation-permeable alloys such as cobalt alloys, gold, platinum, tungsten, alloys containing these elements (for example, platinum-nickel alloys), etc. radiation-impermeable alloys. The cylindrical body 2A is not limited to this, and may be formed of known materials other than the above. In the present embodiment, the entire cylindrical body 2 is formed as a single member of the same material, and its outer diameter is configured to be constant from the tip to the base end.

[0036] At the tip of the guide wire 10A (that is, the tip of the core shaft 1A), a tip chip 3A for joining the core shaft 1A and the cylindrical body 2A is formed. The tip chip 3A is formed of a metal solder such as silver solder, gold solder, zinc, Sn-Ag alloy, Au-Sn alloy, etc. By this metal solder, the tip of the core shaft 1A and the tip of the cylindrical body 2A are fixed. The tip chip 3 may be formed of an adhesive such as an epoxy-based adhesive, and the tip of the core shaft 1A and the tip of the cylindrical body 2A may be fixed by the adhesive.

[0037] At the base end of the cylindrical body 2A, a fixing portion 4A for fixing the core shaft 1A and the cylindrical body 2A is formed. The fixing portion 4A is formed of a metal solder such as silver solder, gold solder, zinc, Sn-Ag alloy, Au-Sn alloy, etc. By this metal solder, the base end of the cylindrical body 2A is fixed to the large-diameter portion 13A of the core shaft 1A. The fixing portion 4A may be formed of an adhesive such as an epoxy-based adhesive, and the large-diameter portion 13A of the core shaft 1A and the base end of the cylindrical body 2A may be fixed by the adhesive.

[0038] Inside the cylindrical body 2A, two joint portions 5Aa and 5Ab for joining the tapered portion 12A of the core shaft 1A and the cylindrical body 2A are formed. The joint portions 5Aa and 5Ab are formed by a metal solder such as silver solder, gold solder, zinc, Sn - Ag alloy, Au - Sn alloy, etc. By this metal solder, the tapered portion 12A of the core shaft 1A and the cylindrical body 2A are fixed. The joint portions 5Aa and 5Ab may be formed by an adhesive such as an epoxy - based adhesive, and the tapered portion 12A of the core shaft 1A and the cylindrical body 2A may be fixed by the adhesive.

[0039] A coating layer such as a silicon coating layer or a hydrophilic coating layer may be formed on the surface of the cylindrical body 2A, the tip chip 3A, the fixing portion 4A, and the surface on the proximal - end side of the large - diameter portion 13A of the core 1A.

[0040] In the guide wire 10A, a knuckle - progression suppression structure is realized by the difference in rigidity between the first region 10Aa located on the distal - end side of the guide wire 10A and the second region 10Ab located on the proximal - end side of the first region 10Aa. The first region 10Aa includes the small - diameter portion 11 of the core shaft 1A, and the second region 10Ab includes the tapered portion 12A and the large - diameter portion 13A of the core shaft 1A. In such a guide wire 10A, the first region 10Aa with low rigidity is provided on the distal - end side, and the second region 10Ab with high rigidity is provided on the proximal - end side. As a result, the guide wire 10A is likely to bend up to the vicinity of the boundary B between the first region 10Aa and the second region 10Ab, and the progression of the knuckle toward the proximal - end side beyond the vicinity of the boundary can be suppressed.

[0041] <Guide wire insertion method> Next, the guide wire insertion method of the present disclosure will be described based on the drawings. This guide wire insertion method is performed when treating ischemic heart disease in the coronary arteries of the heart, and is a method of inserting a guide wire for guiding a catheter for percutaneous coronary intervention (PCI) or the like to a coronary artery stenosis site in a blood vessel having a main tube and a side branch branching from the main tube. As shown in FIG. 3, the guide wire insertion method specifically includes the following steps.

[0042] In step S101, a guide wire GW having a knuckle progression suppression structure is prepared. As the guide wire GW having a knuckle progression suppression structure, the above-described guide wire 10 (the surface of the first region 10a located on the distal end side of the guide wire 10 is less slippery than the surface of the second region 10b located on the proximal end side of the first region 10a, thereby realizing the knuckle progression suppression structure), or the above-described guide wire 10A (the rigidity of the first region 10Aa located on the distal end side of the guide wire and the rigidity of the second region 10Ab located on the proximal end side of the first region 10Aa are different, thereby realizing the knuckle progression suppression structure) can be used.

[0043] In step S102, the operator inserts the guide wire GW into the main tube V of the patient's blood vessel and pushes the distal end T of the guide wire GW toward the affected area. As shown in FIG. 4, the distal end T of the guide wire GW is not knuckled at this stage, and the guide wire GW advances in the main tube V of the blood vessel while remaining substantially straight.

[0044] In step S103, after a knuckle occurs at the distal end portion of the guide wire GW when the distal end T of the guide wire GW catches on the side branch S of the blood vessel, the operator uses the knuckle progression suppression structure to suppress the progression of the knuckle. The state where a knuckle has occurred at the distal end portion of the guide wire GW is shown in FIG. 5. The operator operates the guide wire GW to hook the distal end T of the guide wire GW on the side branch S of the blood vessel, and in this state, by pushing the guide wire GW, a knuckle is generated at the distal end portion of the guide wire GW.

[0045] In step S104, the operator removes the tip T of the guide wire GW from the side branch S, and while maintaining the knuckle in the main tube V, advances the tip portion toward the affected area. The state of advancing the tip portion of the guide wire GW while maintaining the state where the knuckle has occurred is shown in FIG. 6. The operator operates the guide wire GW to remove the tip T of the guide wire GW from the side branch S of the blood vessel, and in this state, by pushing in the guide wire GW, the tip portion of the guide wire GW is delivered to the affected area in the main tube V. Since the guide wire GW has a knuckle progression suppressing structure, even if the operator pushes in the guide wire GW, the knuckle does not progress excessively.

[0046] In step S104, the operator's advancing the tip portion of the guide wire GW in the main tube V may be continued up to a portion where the blood vessel inner diameter is 4 - 6 mm. The general blood vessel diameter of the main tube V is 4 - 6 mm. Therefore, in order for the operator to deliver the tip portion of the guide wire GW to the affected area, it is necessary to continue advancing the tip portion of the guide wire GW in the main tube V up to a portion where the blood vessel inner diameter is 4 - 6 mm.

[0047] In step S104, the operator's advancing the tip portion of the guide wire GW in the main tube V may be continued up to a portion where the blood vessel inner diameter is 1 - 2 mm. In order for the operator to deliver the tip portion of the guide wire GW to the periphery of the main tube V, it is necessary to continuously insert the tip portion of the guide wire GW up to a portion where the blood vessel inner diameter is 1 - 2 mm.

[0048] According to such a guide wire insertion method, the operator hooks the tip T of the guide wire GW on the side branch S of the blood vessel to generate a kink, and in this state, advances the tip portion of the guide wire GW toward the affected area. As a result, the tip T of the guide wire GW will not stray into the fine blood vessels, and in the process of advancing the guide wire GW, its tip T will not be pressed against the blood vessel wall, so it is less likely to cause troubles such as dissociation or perforation of the blood vessel wall. When the operator advances the guide wire GW with a kink generated at the tip portion of the guide wire GW, the generation of the kink may progress to the proximal end side (the side of the operator's hand) of the guide wire GW due to the resistance received from the blood vessel wall. Since the guide wire GW has a kink progression suppressing structure, the progression of the kink is suppressed, so the load on the blood vessel wall is reduced. When the guide wire GW with a kinked tip is advanced, the contact between the guide wire GW and the blood vessel wall becomes line contact instead of point contact, so the load on the blood vessel wall is also suppressed by the reduction of surface pressure.

[0049] As described above, the guide wire insertion method according to the present disclosure and the structure of the guide wire used in the method have been described with reference to the drawings. The present disclosure is not limited to the above embodiments, and various modifications can be implemented.

Claims

1. A guide wire insertion method for inserting a guide wire into a blood vessel having a main tube and a side branch branching from the main tube, comprising: preparing a guide wire having a knuckle progression suppression structure; inserting the guide wire into the main tube of the patient's blood vessel and pushing the tip of the guide wire toward the affected part; after a knuckle is generated at the tip of the guide wire when the tip of the guide wire is caught by a side branch of the blood vessel, suppressing the progression of the knuckle by using the knuckle progression suppression structure; removing the tip of the guide wire from the side branch and pushing the tip forward while maintaining the knuckle toward the affected part within the main tube.

2. The guide wire insertion method according to claim 1, wherein the knuckle progression suppression structure is realized by the surface of a first region located on the tip side of the guide wire being less slippery than the surface of a second region located on the proximal side of the first region.

3. The guide wire insertion method according to claim 1, wherein the knuckle progression suppression structure is realized by the rigidity of a first region located on the tip side of the guide wire being different from the rigidity of a second region located on the proximal side of the first region.

4. The guide wire insertion method according to claim 1, which is performed in the treatment of ischemic heart disease in the coronary arteries of the heart.

5. The guide wire insertion method according to claim 1, wherein pushing the tip forward within the main tube is continued up to a site where the inner diameter of the blood vessel is 4 - 6 mm.

6. The guide wire insertion method according to claim 1, wherein pushing the tip forward within the main tube is continued up to a site where the inner diameter of the blood vessel is 1 - 2 mm.

7. The guide wire insertion method according to claim 1, wherein the guide wire is a workhorse guide wire.

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