Needle catheter

Abstract

This needle catheter comprises: a hollow puncture needle having a curved body section and a puncture section that is provided closer to the tip end side than the body section, has a sharp tip puncture point, and includes a position in the radial direction of the tip puncture point positioned closer to the inside than the outer peripheral surface of the body section; and a shaft disposed closer to the base end side than the puncture needle.

Description

needle catheter

[0001] The present disclosure relates to needle catheters.

[0002] Regenerative therapy methods for regenerating cardiomyocytes whose function has been impaired by myocardial infarction or other conditions are known. For example, Patent Document 1 discloses a therapy method in which cardiomyocytes are prepared in a sheet form outside the body and then attached to the heart to promote cardiomyocyte regeneration. Because the heart beats continuously, it is difficult to stably attach a cell sheet to the heart for an extended period of time. Therefore, a therapeutic method that promotes cardiomyocyte regeneration by injecting a drug solution into cardiomyocytes is anticipated. This therapeutic method is hereinafter also referred to as "drug solution injection therapy." In drug solution injection therapy, a drug solution for promoting cardiomyocyte regeneration is injected into the myocardium through at least one of a coronary artery and a coronary vein. For example, Patent Document 2 discloses a drug solution injection device having a catheter body, a needle-shaped tube having a sharp needle tip, and a drug solution supply means for supplying the drug solution to the needle-shaped tube.

[0003] Japanese Patent No. 5572138 Japanese Patent Laid-Open No. 2004-329487

[0004] In a procedure using the device described in Patent Document 2, the surgeon positions the catheter body at a predetermined location in a blood vessel, then moves the needle-shaped tubular body toward the distal end within the third lumen of the catheter body, causing the needle portion to protrude from a protrusion hole provided at the distal end of the third lumen. The distal end of the needle portion has a sharp shape formed by cutting the tubular body obliquely. Therefore, with the device described in Patent Document 2, when moving the needle-shaped tubular body within the third lumen of the catheter body, the distal end of the needle portion may get caught on the inner wall of the third lumen. As a result, with the device described in Patent Document 2, there is a risk of damage to the catheter body or the needle portion as the needle-shaped tubular body is moved. The needle portion is also called a "puncture needle."

[0005] These problems are not limited to drug injection therapy, but are common to all percutaneous procedures using needle catheters, including those inserted into the body lumen, such as the lymphatic system, biliary system, urinary system, respiratory system, digestive system, secretory glands, and reproductive organs, as well as the vascular system.

[0006] The present disclosure has been made to solve at least part of the above-mentioned problems, and can be realized in the following aspects.

[0007] (1) According to one aspect of the present disclosure, there is provided a needle catheter comprising: a hollow puncture needle having a curved main body portion; a puncture portion provided distally of the main body portion, the puncture portion having a sharp distal puncture point that is radially positioned inwardly of the outer circumferential surface of the main body portion; and a shaft disposed proximal to the puncture needle.

[0008] According to this configuration, the radial position of the sharp tip puncture point of the puncture needle of the needle catheter is located inside the outer circumferential surface of the main body. Therefore, when the needle catheter is moved within the lumen of the combined catheter, the tip puncture point of the puncture needle is prevented from getting caught on the inner wall of the lumen of the combined catheter. As a result, the needle catheter can be moved smoothly within the combined catheter, preventing damage to the combined catheter or the puncture needle. As a result, the difficulty of the procedure during drug solution injection therapy can be reduced, and the procedure time for drug solution injection therapy can be shortened.

[0009] (2) In the needle catheter of the above aspect, the main body portion may include a curved curved portion and a linear first straight portion provided closer to the proximal end than the curved portion, and when the bending width is defined as the distance from the tip puncture point to one of imaginary extension lines of the outer edge of the first straight portion that is farther from the tip puncture point in a side view in which the curved shape of the curved portion can be confirmed, the bending width may be 1.0 mm or more and 10.0 mm or less. With this configuration, the bending width of the puncture needle of the needle catheter is 1.0 mm or more and 10.0 mm or less, thereby achieving both improved deliverability of the needle catheter within the combined catheter and improved protrusion of the puncture needle.

[0010] (3) In the needle catheter of the above aspect, the bending width may be 2.0 mm or more and 5.0 mm or less. With this configuration, the bending width of the puncture needle of the needle catheter is 2.0 mm or more and 5.0 mm or less, which further improves the deliverability of the needle catheter within the combined catheter and further improves the protrusion of the puncture needle.

[0011] (4) In the needle catheter of the above aspect, the main body portion may include a curved curved portion, a linear first straight portion provided proximal to the curved portion, and a linear second straight portion provided distal to the curved portion, and when, in a side view in which the curved shape of the curved portion can be seen, an obtuse angle formed by an imaginary extension line of the outer edge of the first straight portion and an imaginary extension line of the outer edge of the second straight portion is defined as a bending angle, the bending angle may be 100° or more and 170° or less. With this configuration, the bending angle of the puncture needle of the needle catheter is 100° or more and 170° or less, thereby achieving both improved deliverability of the needle catheter within the combined catheter and improved protrusion of the puncture needle.

[0012] (5) In the needle catheter of the above embodiment, the bending angle may be 125° or more and 150° or less. With this configuration, the bending angle of the puncture needle of the needle catheter is 125° or more and 150° or less, which further improves the deliverability of the needle catheter within the combined catheter and further improves the protrusion of the puncture needle.

[0013] (6) In the needle catheter of the above aspect, the puncture portion may include a major cutting edge surface facing a distal opening provided at the tip of the puncture needle, a first surface formed at a position away from the distal opening, and a second surface formed at a position away from the distal opening, and the distal puncture point may be a point where the major cutting edge surface, the first surface, and the second surface intersect. With this configuration, an operator can easily produce a puncture needle having a distal puncture point that is radially inside the outer peripheral surface of the main body by forming the major cutting edge surface by diagonally cutting the tubular body and then forming the first surface and the second surface at positions away from the distal opening.

[0014] The present disclosure can be realized in various forms, for example, in the form of a puncture needle, a set of a puncture needle and a catheter, a needle catheter equipped with a puncture needle, a catheter system equipped with a needle catheter, and methods of manufacturing these.

[0015] 2 is an explanatory diagram illustrating the configuration of a medical system. FIG. 2 is an explanatory diagram illustrating the configuration of a needle catheter. FIG. 2 is a cross-sectional view taken along line A1-A1 of FIG. 2. FIG. 2 is a cross-sectional view taken along line A2-A2 of FIG. 2. FIG. 2 is a cross-sectional view taken along line A3-A3 of FIG. 2. FIG. 2 is an enlarged view of a puncture needle. FIG. 2 is an enlarged view of the tip of the puncture needle. FIG. 2 is an explanatory view of the bending width of the puncture needle. FIG. 2 is an explanatory view of the bending angle of the puncture needle. FIG. 2 is a view of the puncture needle as seen from the tip opening side. FIG. 2 is an enlarged view of the vicinity of the puncture point of the tip of the puncture needle. FIG. 2 is an explanatory diagram showing the heart. FIG. 2 is an explanatory diagram showing a delivery catheter positioned in the vicinity of a treatment target site. FIG. 2 is an explanatory diagram showing the delivery of a needle catheter within a delivery catheter. FIG. 2 is an explanatory diagram showing the tip of the needle catheter positioned in the vicinity of a side opening. FIG. 2 is an explanatory diagram showing the puncture of a myocardium using a needle catheter. FIG. 2 is a graph showing test results regarding the bending width of a puncture needle. FIG. 2 is a graph showing test results regarding the bending angle of a puncture needle. FIG. 2 is an explanatory diagram of a test method for the shape of the puncture portion of a puncture needle. Fig. 10 is a graph showing test results regarding the shape of the puncture part of the puncture needle. Fig. 11 is an enlarged view of the puncture needle of the second embodiment. Fig. 12 is an enlarged view of the tip of the puncture needle of the third embodiment. Fig. 13 is an enlarged view of the tip of the puncture needle of the fourth embodiment. Fig. 14 is a perspective view of the puncture needle of the fourth embodiment.

[0016] First Embodiment FIG. 1 is an explanatory diagram illustrating the configuration of a medical system 1000. The medical system 1000 of this embodiment includes a delivery catheter 1, a needle catheter 2, a stylet wire 3, and a medicinal solution 50. The medical system 1000 is inserted into a body lumen, such as the vascular system, lymphatic system, biliary system, urinary system, respiratory system, digestive system, secretory glands, and reproductive organs, and is used to inject the medicinal solution 50 into body tissue. Hereinafter, medicinal solution injection therapy will be described as an example of a specific application of the medical system 1000. Medicinal solution injection therapy refers to a treatment method in which a medicinal solution containing therapeutic cells is injected into the myocardium through at least one of a coronary artery and a coronary vein to promote the regeneration of cardiomyocytes. The target site of medicinal solution injection therapy is also referred to as the "treatment target site."

[0017] For ease of explanation, FIG. 1 includes some components whose relative size ratios differ from the actual size. FIG. 1 includes some components that are exaggerated. FIG. 1 illustrates mutually orthogonal X, Y, and Z axes. The X axis corresponds to the longitudinal direction of the delivery catheter 1, needle catheter 2, and stylet wire 3. The X axis is also referred to as the axial direction. The Y axis corresponds to the height direction of the delivery catheter 1, needle catheter 2, and stylet wire 3. The Z axis corresponds to the width direction of the delivery catheter 1, needle catheter 2, and stylet wire 3. The left side of FIG. 1 is referred to as the "distal side" of each device and component, and the right side of FIG. 1 is referred to as the "proximal side" of each device and component. The left side of FIG. 1 is the -X axis direction. The right side of FIG. 1 is the +X axis direction. Of the two longitudinal ends of each device and component, the end located closest to the distal end is referred to as the "distal end." Of the longitudinal ends of each device and each component, the end located on the base end side is referred to as the "base end." The tip and its vicinity are referred to as the "tip portion." The base and its vicinity are referred to as the "base end portion." The tip side is inserted into the living body, and the base side is operated by an operator such as a doctor. These points are also common to Figure 2 and subsequent figures. In this embodiment, "same" and "equal" mean roughly the same, and allow for variations due to manufacturing errors, etc. In this embodiment, "constant" also includes roughly constant, and allow for variations due to manufacturing errors, etc.

[0018] The delivery catheter 1 is a catheter for delivering the needle catheter 2 to the treatment site. As shown in Figure 1, the delivery catheter 1 includes a distal tip 11, a first shaft 12, a marker M, and a catheter connector 19. The delivery catheter 1 is a single-lumen catheter having only a first lumen 1L. The delivery catheter 1 has a side opening OP.

[0019] The distal tip 11 is provided at the distal end of the first shaft 12 and moves through the blood vessel ahead of other components. The distal tip 11 is a cylindrical component with an outer diameter that gradually decreases from the proximal end to the distal end. A distal opening 1a is formed at the distal end of the distal tip 11. The distal opening 1a is an opening for inserting another device into the delivery catheter 1. An example of another device is a delivery guide wire known as a workhorse wire.

[0020] The first shaft 12 is a tubular body having a first lumen 1L therein and an elongated outer shape. The first shaft 12 includes a distal shaft 12D and a proximal shaft 12P. A side opening OP is provided on the side surface of the distal shaft 12D. The side opening OP is a through-hole formed on the side surface of the distal shaft 12D of the delivery catheter 1, and is a through-hole that connects the first lumen 1L to the outside. The side opening OP is an opening through which the distal end of the needle catheter 2 protrudes from the delivery catheter 1. The shape of the side opening OP as viewed from the -Y axis direction is approximately rectangular. The shape of the side opening OP as viewed from the -Y axis direction may be a shape other than approximately rectangular. Examples of different shapes include a circle, a square, and a polygon. A radiopaque marker M is provided on the distal shaft 12D near the side opening OP. The marker M is a mark that allows the surgeon to confirm the orientation of the side opening OP under an X-ray image. X-ray images are also called an angio image. A distal tip 11 is fixed to the distal end of the distal shaft 12D. A catheter connector 19 is fixed to the proximal end of the proximal shaft 12P.

[0021] The catheter connector 19 is attached to the proximal end of the first shaft 12, making it easy for the surgeon to grasp the device. The catheter connector 19 is a substantially cylindrical member provided with a pair of wings. A proximal end opening 1b is formed at the proximal end of the catheter connector 19. The proximal end opening 1b is an opening for inserting a needle catheter 2 or other device into the delivery catheter 1. An example of the other device is a work hose wire.

[0022] As shown by dashed lines in Figure 1, the distal tip 11, first shaft 12, and catheter connector 19 have a first lumen 1L formed therein that runs through the interior of each section along the longitudinal direction of the delivery catheter 1. The first lumen 1L is a lumen into which the needle catheter 2 or other devices are inserted. The inner diameter Φ1L of the first lumen 1L may be determined arbitrarily as long as it is larger than the outer diameter of the second shaft 22 of the needle catheter 2. The base end of the first lumen 1L communicates with the outside through a base end opening 1b. The tip of the first lumen 1L communicates with the outside through a tip opening 1a. The tip of the first lumen 1L communicates with the outside through a side opening OP.

[0023] The distal tip 11 can be formed from a flexible resin material, such as polyurethane elastomer. The distal tip 11 may also be formed from a radiopaque resin or metal material. For example, when using a radiopaque resin material, the distal tip 11 can be formed by mixing a radiopaque material such as bismuth trioxide, tungsten, or barium sulfate with polyamide resin, polyolefin resin, polyester resin, polyurethane resin, silicone resin, or fluororesin. For example, when using a radiopaque metal material, the distal tip 11 can be formed from at least one of gold, platinum, and tungsten. The distal tip 11 may also be formed from an alloy containing at least one of gold, platinum, and tungsten. The first shaft 12 and the catheter connector 19 can be formed from known materials, such as nylon resin, polyolefin, polyester, thermoplastic resin, polyamide elastomer, polyolefin elastomer, polyurethane elastomer, silicone rubber, and latex rubber. An example of a nylon resin is polyamide. Examples of polyolefins include polyethylene, polypropylene, and ethylene-propylene copolymers. Examples of polyesters include polyethylene terephthalate. Examples of thermoplastic resins include polyvinyl chloride, ethylene-vinyl acetate copolymers, cross-linked ethylene-vinyl acetate copolymers, and polyurethanes.

[0024] The needle catheter 2 is a catheter for injecting a medicinal solution into the myocardium. As shown in Fig. 1, the needle catheter 2 includes a puncture needle 21, a second shaft 22, a needle marker 24, and a connector 29. The needle catheter 2 is a single-lumen catheter having only a second lumen 2L. The puncture needle 21 is fixed to the tip of the needle catheter 2.

[0025] The puncture needle 21 is a hollow puncture needle attached to the tip of the second shaft 22. The puncture needle 21 is also simply referred to as a "needle." The tip of the puncture needle 21 has a sharp shape to facilitate puncturing body tissue. The puncture needle 21 is curved in a specific direction. In the example shown, the puncture needle 21 is curved in the -Y axis direction. The inner cavity of the puncture needle 21 forms part of the second lumen 2L. A tip opening 2a is formed at the tip of the puncture needle 21. The tip opening 2a is used to project the stylet wire 3 during delivery of the needle catheter 2, and is an opening used to eject the medicinal solution during medicinal solution injection through the needle catheter 2. The puncture needle 21 may be configured integrally with the first shaft 12.

[0026] The second shaft 22 is a tubular body having a second lumen 2L therein and an elongated outer shape. The second shaft 22 is disposed proximal to the puncture needle 21. The second shaft 22 includes a distal shaft 22D and a distal shaft 22P. A radiopaque needle marker 24 is provided at the distal end of the distal shaft 22D. The needle marker 24 serves as a guide for the surgeon to confirm the position of the puncture needle 21 under X-ray imaging. The needle marker 24 is annular and surrounds the entire circumference of the distal shaft 22D. The needle marker 24 may have any shape other than annular, or may be omitted. The needle marker 24 can be formed from a radiopaque resin material or metal material. The puncture needle 21 is fixed to the distal end of the distal shaft 22D. A connector 29 is fixed to the proximal end of the proximal shaft 22P.

[0027] The connector 29 is attached to the proximal end of the second shaft 22 to facilitate grasping of the device by the surgeon. The connector 29 is also used by the surgeon when introducing the medicinal solution 50 into the second lumen 2L. The connector 29 is a generally cylindrical member provided with a pair of wings. A proximal end opening 2b is formed at the proximal end of the connector 29. The proximal end opening 2b is an opening for inserting the stylet wire 3 or other devices into the needle catheter 2. Examples of other devices include a syringe. The connector 29 can be formed from a well-known resin material. As shown in FIG. 1 , the connector 29 of the needle catheter 2 has a shorter longitudinal length than the catheter connector 19 of the delivery catheter 1. The connector 29 of the needle catheter 2 has a smaller internal space capacity than the catheter connector 19 of the delivery catheter 1. These features are intended to reduce the amount of medicinal solution 50 remaining inside the connector 29 after the completion of the medicinal solution injection treatment procedure, thereby preventing waste of the medicinal solution 50. The connector 29 of the needle catheter 2 may have the same shape as the catheter connector 19 of the delivery catheter 1 .

[0028] As shown by the dashed lines in Figure 1, the puncture needle 21, the second shaft 22, and the connector 29 have a second lumen 2L formed in them along the longitudinal direction of the needle catheter 2, passing through the interior of each part. The second lumen 2L is a lumen for inserting the stylet wire 3. The second lumen 2L is a lumen for flowing the medicinal solution 50. The inner diameter Φ2L of the second lumen 2L may be determined arbitrarily as long as it is larger than the outer diameter Φ3 of the stylet wire 3. The distal end of the second lumen 2L communicates with the outside through a distal opening 2a. The proximal end of the second lumen 2L communicates with the outside through a proximal opening 2b.

[0029] The stylet wire 3 is a wire that protects the delivery catheter 1 and the needle catheter 2 and provides rigidity to the needle catheter 2 to facilitate delivery of the needle catheter 2 when the medical system 1000 is in use. The stylet wire 3 includes a core wire and a coil. For convenience of illustration, the core wire and coil are omitted from Figure 1.

[0030] The core wire is a cylindrical member having an elongated outer shape. The core wire may have a constant outer diameter. The core wire may have an outer diameter that decreases from the base end to the tip end. The coil is formed by spirally winding a wire. The coil is disposed so as to surround a portion of the core wire at the tip end and is fixed to the core wire. The coil may be disposed so as to surround the entire core wire from the tip to the base end. The outer diameter Φ3 of the coil is defined as the outer diameter of the stylet wire 3. In this embodiment, the outer diameter Φ3 of the stylet wire 3 is the smallest inner diameter of the puncture needle 21 of the needle catheter 2 minus a predetermined clearance value. The smallest inner diameter of the puncture needle 21 is the inner diameter of the tip of the puncture needle 21. The tip of the puncture needle 21 of the needle catheter 2 has an inner diameter that is the outer diameter Φ3 of the stylet wire 3 plus a predetermined clearance value.

[0031] The core wire can be formed using at least one of, for example, a stainless steel alloy, a superelastic alloy, a piano wire, a nickel-chromium alloy, a cobalt alloy, and tungsten. Examples of stainless steel alloys include SUS302, SUS304, and SUS316. Examples of superelastic alloys include nickel-titanium. The core wire may be formed using known materials other than those listed above. The coil can be formed using at least one of, for example, a stainless steel alloy, a superelastic alloy, a radiolucent alloy, and a radiopaque alloy. Examples of stainless steel alloys include SUS304 and SUS316. Examples of superelastic alloys include nickel-titanium alloys. Examples of radiolucent alloys include piano wire, a nickel-chromium alloy, and a cobalt alloy. Examples of radiopaque alloys include gold, platinum, tungsten, and alloys containing these elements. The coil may be formed using known materials other than those listed above.

[0032] FIG. 2 is an explanatory diagram illustrating the configuration of the needle catheter 2. FIG. 3 is a cross-sectional view taken along line A1-A1 in FIG. 2. FIG. 4 is a cross-sectional view taken along line A2-A2 in FIG. 2. FIG. 5 is a cross-sectional view taken along line A3-A3 in FIG. 2. In FIGS. 2 to 5, the center line of the needle catheter 2 is shown as axis O. Axis O coincides with the axis passing through the center of the second shaft 22. The configuration of the needle catheter 2 will be described in detail below.

[0033] The distal shaft 22D is a portion located closer to the proximal end than the puncture needle 21, between the puncture needle 21 and the proximal shaft 22P. As shown in FIG. 4 , the distal shaft 22D has a coil 221 and a tube 222.

[0034] The tube 222 maintains the liquid-tightness of the second lumen 2L of the needle catheter 2. The tube 222 is a tubular body having an elongated outer shape. The distal end of the tube 222 is joined to the proximal end of the puncture needle 21. The proximal end of the tube 222 is joined to the distal end of the connector 29. For joining, metal solder or an adhesive such as an epoxy adhesive or a cyanoacrylic adhesive can be used. The tube 222 can be made of a resin with excellent chemical resistance, such as a polyimide resin.

[0035] The coil 221 provides a predetermined rigidity and flexibility to the first shaft 12 of the needle catheter 2. The coil 221 is provided to improve the deliverability of the needle catheter 2. The coil 221 is a multi-thread coil formed by winding multiple strands of wire. The coil 221 is arranged to surround the outer circumferential surface of the tube 222. In the illustrated example, the inner circumferential surface of the coil 221 and the outer circumferential surface of the tube 222 are in contact with each other. The distal end of the coil 221 is bonded to the tube 222 and the puncture needle 21, respectively. The proximal end of the coil 221 is bonded to the distal end of the connector 29. For bonding, a metal solder or an adhesive such as an epoxy adhesive or a cyanoacrylic adhesive can be used. Bonding may be performed using two or more means in combination.

[0036] The coil 221 can be formed using at least one of a stainless steel alloy, a superelastic alloy, a radiolucent alloy, and a radiopaque alloy. Examples of stainless steel alloys include SUS304 and SUS316. Examples of superelastic alloys include a nickel-titanium alloy. Examples of radiolucent alloys include piano wire, a nickel-chromium alloy, and a cobalt alloy. Examples of radiopaque alloys include gold, platinum, tungsten, and alloys containing these elements. The coil 221 may also be formed using known materials other than those mentioned above. The coil 221 may be a single-strand coil formed by winding a single wire into a single strand. The coil 221 may be a single-strand stranded coil formed by winding a strand formed by twisting multiple wires together into a single strand. The coil 221 may be a multi-strand stranded coil formed by using multiple strands of wires twisted together, and winding each strand into multiple strands. As shown in FIG. 2, the distal shaft 22D is a section S22 extending from the base end of the needle marker 24 to the boundary between the distal shaft 22D and the base shaft 22P.

[0037] The proximal shaft 22P is a portion located closer to the proximal end than the distal shaft 22D, and between the distal shaft 22D and the connector 29. As shown in Fig. 5 , the proximal shaft 22P has a shaft 231, a coil 221, and a tube 222. The coil 221 is the same member as the coil 221 described in Fig. 4. The tube 222 is the same member as the tube 222 described in Fig. 4.

[0038] The shaft 231 imparts a predetermined rigidity and torque transmission capability to the proximal shaft 22P of the needle catheter 2. The shaft 231 is provided to improve the deliverability of the needle catheter 2. The shaft 231 is a tubular body having an elongated outer shape. The shaft 231 is disposed so as to surround the outer circumferential surface of the coil 221. In the illustrated example, the inner circumferential surface of the shaft 231 and the outer circumferential surface of the coil 221 are in contact with each other. The distal end of the shaft 231 is bonded to a portion of the coil 221. The proximal end of the shaft 231 is bonded to the connector 29. For bonding, metal solder or an adhesive such as an epoxy adhesive or a cyanoacrylic adhesive can be used. Bonding may be performed using two or more means in combination.

[0039] The shaft 231 can be formed of any known material, such as a stainless steel alloy or a superelastic alloy. Examples of stainless steel alloys include SUS302, SUS304, and SUS316. Examples of superelastic alloys include nickel-titanium alloys. As shown in FIG. 2 , the proximal shaft 22P is a section S23 extending from the boundary between the distal shaft 22D and the proximal shaft 22P to the distal end of the connector 29. In the needle catheter 2 of this embodiment, the longitudinal lengths of the distal shaft 22D and the proximal shaft 22P are approximately equal. The longitudinal lengths of the distal shaft 22D and the proximal shaft 22P may differ.

[0040] FIG. 6 is an enlarged view of the puncture needle 21. FIG. 7 is an enlarged view of the tip of the puncture needle 21. In FIG. 7, the inner cavity of the puncture needle 21, which constitutes part of the second lumen 2L, is indicated by a dashed line. The puncture needle 21 is the most distal portion of the needle catheter 2. As shown in FIG. 6, at the base end of the puncture needle 21, the center of the puncture needle 21 coincides with the axis O. The distal end of the puncture needle 21 is given a curved shape that is curved in a specific direction. In the illustrated example, this specific direction is the -Y-axis direction. The puncture needle 21 can be formed from a metal with shape memory properties. Examples of metals with shape memory properties include nickel-titanium alloys and CuZnAl alloys. As shown in FIG. 2, the puncture needle 21 is provided in a section S21 from the tip of the puncture needle to the tip of the needle marker 24.

[0041] As shown in FIG. 6 , the puncture needle 21 has, from the base end to the tip end, a first straight portion 211, a curved portion 213, a second straight portion 212, and a puncture portion 214. The first straight portion 211 is a linear portion of the puncture needle 21 that is located closer to the base end than the curved portion 213. In the first straight portion 211, the puncture needle 21 extends linearly along the axis O. The curved portion 213 is a curved portion of the puncture needle 21. The curved portion 213 is curved in a direction that points the tip of the puncture needle 21 in the −Y axis direction. The direction of curvature of the curved portion 213 is not limited to the −Y axis direction and can be determined arbitrarily. The second straight portion 212 is a linear portion of the puncture needle 21 that is located closer to the tip end than the curved portion 213. The first straight portion 211, the curved portion 213, and the second straight portion 212 are also collectively referred to as the "main body portion 210." The main body portion 210 has a tubular shape with a substantially constant outer diameter Φ210. The inner cavity of the main body portion 210 constitutes a part of the second lumen 2L. The outer diameter Φ210 of the main body portion 210 may gradually decrease from the base end toward the tip.

[0042] The puncture portion 214 is a portion of the puncture needle 21 that is located closer to the tip than the main body portion 210. The puncture portion 214 is the most distal portion of the puncture needle 21. As shown in FIG. 7 , the puncture portion 214 is formed by diagonally cutting the tubular main body portion 210. The puncture portion 214 is a portion that includes the cut surface at the tip of the puncture needle 21. The outer diameter of the puncture portion 214 is smaller than the outer diameter Φ210 of the main body portion 210. As shown in FIG. 7 , the outer diameter of the puncture portion 214 gradually decreases from the base end side toward the tip end side. The puncture portion 214 is provided with a distal opening 2a that communicates with the second lumen 2L.

[0043] The puncturing portion 214 has a tip puncturing point TP. The tip puncturing point TP is a portion that includes the tip of the puncturing portion 214. The tip puncturing point TP is sharp. The tip puncturing point TP is a portion of the tip of the puncturing portion 214 that is thinner and sharper than the other portions. FIG. 7 shows imaginary extension lines VL212a, b of the outer peripheral surface of the main body portion 210. The imaginary extension line VL212a is an imaginary extension line that is located on the side of the outer peripheral surface of the main body portion 210 opposite the bending direction of the curved portion 213. The imaginary extension line VL212b is an imaginary extension line that is located on the side of the outer peripheral surface of the main body portion 210 in the bending direction of the curved portion 213. The imaginary extension lines VL212a, b are imaginary extension lines of the outer peripheral surface of the second straight portion 212. The position of the tip puncture point TP is located inside the imaginary extension line VL212a and inside the imaginary extension line VL212b in the radial direction of the puncture needle 21. Therefore, it can be said that the position of the tip puncture point TP is located inside the outer peripheral surface of the main body 210 in the radial direction of the puncture needle 21.

[0044] FIG. 8 is a diagram illustrating the bending width of the puncture needle 21. FIG. 8 shows the puncture needle 21 in a side view in which the bending shape of the bending portion 213 can be confirmed. A side view in which the bending shape of the bending portion 213 can be confirmed means that the puncture needle 21 is viewed from a direction in which the bending width W21 (described later) appears to be the longest and in which the first straight portion 211, the bending portion 213, the second straight portion 212, and the puncture portion 214 can all be confirmed. In this side view, of the imaginary extension lines of the outer edge of the first straight portion 211, one imaginary extension line farthest from the tip puncture point TP is designated VL211. As shown in FIG. 8 , the distance W21 from the tip puncture point TP to the imaginary extension line VL211 is referred to as the "bending width" of the puncture needle 21. The distance W21 is the length from the tip puncture point TP to the imaginary extension line VL211 in a direction perpendicular to the axis O. In the needle catheter 2 of this embodiment, the bending width W21 of the puncture needle 21 is 1.0 mm or more and 10.0 mm or less. The bending width W21 of the puncture needle 21 is preferably 2.0 mm or more and 5.0 mm or less. The bending width W21 of the puncture needle 21 is more preferably 3.0 mm or more and 4.0 mm or less.

[0045] FIG. 9 is a diagram illustrating the bending angle of the puncture needle 21. Similar to FIG. 8 , FIG. 9 shows the puncture needle 21 in a side view in which the curved shape of the curved portion 213 can be confirmed. In this side view, of the imaginary extension lines of the outer edge of the first straight portion 211, the outermost imaginary extension line is designated VL211. Of the imaginary extension lines of the outer edge of the second straight portion 212, the outermost imaginary extension line is designated VL212. As shown in FIG. 9 , the obtuse angle θ21 formed between the imaginary extension lines VL211 and VL212 is referred to as the "bending angle" of the puncture needle 21. In the needle catheter 2 of this embodiment, the bending angle θ21 of the puncture needle 21 is 100° or more and 170° or less. It is preferable that the bending angle θ21 of the puncture needle 21 be 125° or more and 150° or less. It is more preferable that the bending angle θ21 of the puncture needle 21 is 135° or more and 145° or less. In the example of Fig. 9, the bending angles of the first straight portion 211 and the second straight portion 212 are defined using the respective outer imaginary extension lines. The bending angles of the first straight portion 211 and the second straight portion 212 may also be defined using the respective inner imaginary extension lines. The bending angle defined using the outer imaginary extension lines and the bending angle defined using the inner imaginary extension lines are the same angle.

[0046] Fig. 10 is a diagram showing the puncture needle 21 as seen from the tip opening 2a side. Fig. 11 is an enlarged view of the vicinity of the tip puncture point TP of the puncture needle 21. Fig. 10 shows the puncture needle 21 as seen from direction B in Fig. 7. In Figs. 10 and 11, planar surfaces are indicated by dot hatching. The puncture portion 214 includes a major cutting edge 215, a first surface 216, and a second surface 217.

[0047] As shown in FIG. 10 , the major blade surface 215 is a plane facing the distal end opening 2 a of the puncture needle 21. The major blade surface 215 is a plane surrounding the distal end opening 2 a. The first surface 216 is a plane formed at a position away from the distal end opening 2 a of the puncture needle 21. As shown in FIG. 11 , the first surface 216 is a part of the side surface of the puncture needle 21 that is located outside the puncture needle 21 in a side view in which the curved shape of the curved portion 213 can be seen, and is provided on a part adjacent to the major blade surface 215. The second surface 217 is a plane formed at a position away from the distal end opening 2 a of the puncture needle 21 and different from the first surface 216. As shown in FIG. 11 , the second surface 217 is a part of the side surface of the puncture needle 21 that is located outside the puncture needle 21 in a side view in which the curved shape of the curved portion 213 can be seen, and is provided on a part adjacent to the major blade surface 215 and facing the first surface 216. The tip puncture point TP is the point where the main cutting surface 215, the first surface 216, and the second surface 217 intersect.

[0048] FIG. 12 is an explanatory diagram showing a heart. FIG. 12 shows a heart 90, a guiding catheter 4 inserted into the heart 90, a delivery catheter 1, and a needle catheter 2. FIG. 13 is an explanatory diagram showing a delivery catheter 1 positioned near a treatment target site. FIG. 14 is an explanatory diagram showing the needle catheter 2 being delivered within the delivery catheter 1. FIG. 15 is an explanatory diagram showing the tip of the needle catheter 2 positioned near a side opening OP. FIG. 16 is an explanatory diagram showing the needle catheter 2 being used to puncture a myocardium 96. In FIGS. 13 to 16, both the delivery catheter 1 and the device within the first lumen 1L of the delivery catheter 1 are illustrated with solid lines. Hereinafter, a surgical method for drug solution injection therapy will be described using FIGS. 12 to 16. In the following examples, a procedure via the coronary artery will be illustrated. A procedure via the coronary vein may also be used. This drug solution injection therapy may be performed simultaneously with a percutaneous coronary intervention procedure or independently.

[0049] Returning to FIG. 12 , the explanation will continue. For example, the surgeon can perform the procedure for drug solution injection therapy by the following steps a1 to a11. (a1) The surgeon inserts the work horse wire 5 from the patient's wrist or thigh. The surgeon delivers the work horse wire 5 to the vicinity of the treatment target site in the left coronary artery 94. The work horse wire 5 is a guide wire for delivery. (a2) The surgeon inserts the work horse wire 5 from the tip of the guiding catheter 4 and delivers the guiding catheter 4 along the work horse wire 5 to the entrance of the left coronary artery 94. (a3) ​​The surgeon inserts the work horse wire 5 from the tip of the delivery catheter 1. The surgeon pushes the delivery catheter 1 along the work horse wire 5 inside the guiding catheter 4. In this way, the surgeon uses the guiding catheter 4 to guide the delivery catheter 1 to the entrance of the left coronary artery 94. (a4) The surgeon pushes the delivery catheter 1 into the left coronary artery 94. As shown in FIG. 13 , the surgeon delivers the delivery catheter 1 until the side opening OP of the delivery catheter 1 reaches a position in the left coronary artery 94 near the treatment target site. At this time, while referring to the marker M in the X-ray image, the surgeon adjusts the circumferential orientation of the delivery catheter 1 so that the side opening OP of the delivery catheter 1 is positioned on the myocardium 96 side, as shown in FIG. 13 . The surgeon then removes the workpiece wire 5 from the delivery catheter 1. (a5) The surgeon inserts the stylet wire 3 into the needle catheter 2 until the tip of the stylet wire 3 protrudes from the distal opening 2a. The surgeon inserts the needle catheter 2 with the stylet wire 3 inserted into the delivery catheter 1. At this time, the surgeon gently bends the puncture needle 21 of the needle catheter 2 until the bending width W21 of the puncture needle 21 is equal to or smaller than the inner diameter of the delivery catheter 1. The surgeon then pushes the needle catheter 2 toward the distal end within the delivery catheter 1.

[0050] As described in step a5, the needle catheter 2 is delivered through the delivery catheter 1 with the stylet wire 3 inserted into the second lumen 2L and a portion of the stylet wire 3 protruding from the tip of the puncture needle 21. This allows the stylet wire 3 to protect the puncture site 214 of the puncture needle 21, thereby preventing damage to the inner circumferential surface 12i of the delivery catheter 1 and the puncture site 214 of the puncture needle 21 during delivery of the needle catheter 2. The delivery catheter 1 is delivered from the patient's wrist or thigh to the treatment site within the left coronary artery 94. At the curved portion of the blood vessel, the delivery catheter 1 is curved significantly. Within the first lumen 1L of the curved delivery catheter 1, as shown in FIG. 14 , the leading edge of the puncture needle 21 may float above the stylet wire 3. If the surgeon pushes the needle catheter 2 forward in this state, the leading edge of the puncture needle 21 may become caught on the inner circumferential surface 12i of the delivery catheter 1. 14, the tip of the puncture needle 21 is indicated by a dashed circle. In this regard, in the needle catheter 2 of this embodiment, the tip puncture point TP of the puncture needle 21 is located inside the outer circumferential surface of the main body 210, which prevents the tip puncture point TP from piercing the inner circumferential surface 12i. Therefore, in the needle catheter 2 of this embodiment, the puncture needle 21 does not get caught even in the first lumen 1L of the curved delivery catheter 1.

[0051] (a6) The surgeon pushes the needle catheter 2 forward and delivers the needle catheter 2 until the tip of the needle catheter 2 is located near the side opening OP of the delivery catheter 1. The state at this time is shown in Figure 15. After delivering the needle catheter 2, the surgeon removes the stylet wire 3 from the needle catheter 2. (a7) The surgeon injects the medicinal solution 50 into the needle catheter 2. The surgeon prepares a syringe filled with the medicinal solution 50. The surgeon inserts the nozzle of the syringe into the connector 29 of the needle catheter 2 and pushes in the syringe plunger. This supplies the medicinal solution 50 in the syringe to the second lumen 2L of the needle catheter 2. The surgeon continues supplying the medicinal solution 50 until the second lumen 2L of the needle catheter 2 is filled with the medicinal solution 50. (a8) The surgeon punctures the myocardium 96 using the needle catheter 2. As shown in FIG. 16 , the surgeon pushes the needle catheter 2 in the direction of the white arrow while fixing the position of the delivery catheter 1. This allows the surgeon to protrude the puncture needle 21 of the needle catheter 2 from the side opening OP of the delivery catheter 1 and puncture the puncture needle 21 into the myocardium 96. The surgeon pushes the tip of the puncture needle 21 to the target position within the myocardium 96 while checking the resistance felt by the surgeon's hand due to the puncture and the image of the puncture needle 21 under X-ray imaging. The target position is the position within the myocardium 96 where the surgeon intends to inject the medicinal solution 50. (a9) After inserting the puncture needle 21 into the target position, the surgeon pushes the plunger of the syringe to inject the medicinal solution 50 into the tissue of the myocardium 96. If the medicinal solution 50 contains a radiopaque component, the surgeon can inject the medicinal solution 50 while observing the injection of the medicinal solution 50 into the myocardium 96 under X-ray imaging. (a10) After completing the injection of the medicinal solution 50, the surgeon slowly retracts the needle catheter 2 toward the operator. This withdraws the puncture needle 21 of the needle catheter 2 from the myocardium 96. The surgeon then retracts the needle catheter 2 further toward the operator, thereby storing the puncture needle 21 of the needle catheter 2 within the first lumen 1L of the delivery catheter 1. At this time, it is preferable for the surgeon to position the tip of the needle catheter 2 just before the side opening OP of the delivery catheter 1. The surgeon moves the delivery catheter 1 within the left coronary artery 94 and repeats the above procedure as many times as desired.In this way, by moving the delivery catheter 1 to different positions in the left coronary artery 94 and repeating the procedure, the medicinal solution 50 can be injected into different positions in the myocardium 96. The surgeon may also inject the medicinal solution 50 into the myocardium 96 via the right coronary artery 95 in a similar manner. The surgeon may inject the medicinal solution 50 only through the right coronary artery 95 instead of the left coronary artery 94, or through both the left coronary artery 94 and the right coronary artery 95. (a11) The surgeon confirms that the injection of the medicinal solution 50 into the treatment target area has been completed at the predetermined location and with a predetermined amount of medicinal solution 50. To achieve the desired effect of medicinal solution injection therapy, the number of cells contained in the predetermined amount of medicinal solution 50 is preferably approximately 100 million or more per patient. After confirmation, the surgeon removes all devices except the guiding catheter 4 from the left coronary artery 94. The surgeon uses the guiding catheter 4 to inject a contrast agent into the left coronary artery 94 and acquires an X-ray image. The surgeon checks the X-ray image to determine whether there is any blood leakage from the left coronary artery 94. If there is no blood leakage, the surgeon removes the guiding catheter 4 and completes the procedure.

[0052] In this way, in the drug solution injection therapy, the drug solution 50 containing therapeutic cells is injected directly into the myocardial tissue from the puncture needle 21 of the needle catheter 2, so the therapeutic effect of the drug solution 50 can be improved compared to when the drug solution 50 is administered by other means. As a result, the efficiency of the drug solution injection therapy procedure can be improved. This drug solution injection therapy can reduce the physical burden on the patient compared to surgical treatment methods, and can be expected to improve the quality of life after treatment.

[0053] Figure 17 is a graph showing test results regarding the bending width W21 of the puncture needle 21. In this test, the operator prepared four needle catheter 2 samples with the bending width W21 of the puncture needle 21 set to the values ​​shown in Figure 17. Using each sample, the operator performed steps a1 to a8 of drug solution injection treatment on animals and evaluated the deliverability and protrusion. The delivery catheter 1 and stylet wire 3 used in steps a1 to a8 were the same.

[0054] Deliverability refers to the ease of delivery of the needle catheter 2 within the delivery catheter 1. In this test, a rating of A was given when the surgeon felt there was little resistance during delivery. A rating of B was given when the surgeon felt there was much resistance during delivery. A rating of C was given when the delivery catheter 1 got stuck during delivery and could not reach the side opening OP of the delivery catheter 1. Protrusion refers to the ease with which the puncture needle 21 can be protruded from the side opening OP of the delivery catheter 1. In this test, a rating of A was given when the surgeon felt that the puncture needle 21 could be smoothly protruded from the side opening OP. A rating of B was given when the surgeon was able to protrude the puncture needle 21 from the side opening OP but felt that the operation was somewhat difficult. A rating of C was given when the surgeon was able to protrude the puncture needle 21 from the side opening OP but felt that the operation was very difficult. A rating of D was given when the surgeon was unable to protrude the puncture needle 21 from the side opening OP.

[0055] 17, when the bending width W21 of the puncture needle 21 was 3.5 mm, the deliverability and protrusion were both rated A. When the bending width W21 of the puncture needle 21 was 4.0 mm, the deliverability and protrusion were both rated A. When the bending width W21 of the puncture needle 21 was 4.5 mm, the deliverability was rated B and the protrusion was rated A. When the bending width W21 of the puncture needle 21 was 5.0 mm, the deliverability was rated B and the protrusion was rated A. These test results show that in order to obtain a needle catheter 2 that is excellent in both deliverability and protrusion, it is most preferable that the bending width W21 of the puncture needle 21 be 3.0 mm or more and 4.0 mm or less.

[0056] Figure 18 is a graph showing test results regarding the bending angle θ21 of the puncture needle 21. In this test, the operator prepared 11 needle catheter 2 samples with the bending angle θ21 of the puncture needle 21 set to the values ​​shown in Figure 18. Using each sample, the operator performed steps a1 to a8 of drug solution injection treatment on animals and evaluated deliverability and protrusion. The delivery catheter 1 and stylet wire 3 used in steps a1 to a8 were the same. The meaning and evaluation method of deliverability and protrusion are the same as those in Figure 17.

[0057] As shown in Figure 18, when the bending angle θ21 of the puncture needle 21 was 90°, the deliverability was rated C and the protrusion was rated A. When the bending angle θ21 of the puncture needle 21 was 120°, the deliverability was rated B and the protrusion was rated A. When the bending angle θ21 of the puncture needle 21 was 135°, the deliverability and protrusion were both rated A. When the bending angle θ21 of the puncture needle 21 was 140°, the deliverability and protrusion were both rated A. When the bending angle θ21 of the puncture needle 21 was 141°, the deliverability and protrusion were both rated A. When the bending angle θ21 of the puncture needle 21 was 143°, the deliverability and protrusion were both rated A. When the bending angle θ21 of the puncture needle 21 was 145°, the deliverability and protrusion were both rated A. When the bending angle θ21 of the puncture needle 21 was 150°, the deliverability was rated A and the protrusion was rated B. When the bending angle θ21 of the puncture needle 21 was 160°, the deliverability was rated A and the protrusion was rated C. When the bending angle θ21 of the puncture needle 21 was 170°, the deliverability was rated A and the protrusion was rated C. When the bending angle θ21 of the puncture needle 21 was 175°, the deliverability was rated A and the protrusion was rated D. These test results show that in order to obtain a needle catheter 2 that is excellent in both deliverability and protrusion, it is most preferable that the bending angle θ21 of the puncture needle 21 be 135° or more and 145° or less.

[0058] FIG. 19 is an explanatory diagram of a test method for the shape of the puncture portion 214 of the puncture needle 21. FIG. 20 is a graph showing test results for the shape of the puncture portion 214 of the puncture needle 21. This test was conducted according to the following steps b1 to b5. (b1) An operator prepared seven test devices 80 each having the shape shown in FIG. 19 and each having the radius of curvature R of the curve 803 shown in FIG. 20. The test device 80 simulates a human blood vessel. As shown in FIG. 19, the test device 80 has a housing 801 and a transparent tube 802. The housing 801 is a transparent resin member for fixing the transparent tube 802. The transparent tube 802 is arranged with a curve 803 inside the housing 801. The seven test devices 80 have the radius of curvature R of the curve 803 of the transparent tube 802 having different values ​​as shown in FIG. 20. (b2) The operator prepared three needle catheter 2 samples S1 to S3, each having a different shape for the puncture portion 214 of the puncture needle 21. Sample S1 is a needle catheter 2 having the puncture needle 21 of this embodiment. Specifically, the puncture needle 21 of sample S1 has a tip puncture point TP located inside the outer circumferential surface of the main body 210, as described in FIG. 7 . Sample S2 is a needle catheter having a puncture needle different from the puncture needle 21 of this embodiment. Specifically, the tip puncture point of the puncture needle of sample S2 is located on an imaginary extension of the outer circumferential surface of the main body. The puncture needle of sample S2 has a major cutting edge surface facing the tip opening that includes two planes at different angles. Sample S3 is a needle catheter having a puncture needle different from the puncture needle 21 of this embodiment. Specifically, the tip puncture point of the puncture needle of sample S3 is located on an imaginary extension of the outer circumferential surface of the main body. The puncture needle of sample S3 has a single flat main cutting edge facing the tip opening. The bending width W21 of the puncture needles of samples S1 to S3 is 3.5 mm. The bending angle θ21 of the puncture needles of samples S1 to S3 is 140°. (b3) The surgeon inserted the delivery catheter 1 described in FIG. 1 into the transparent tube 802 of the first test device 80 and delivered the delivery catheter 1 to the distal end side of the curve 803. The surgeon inserted the stylet wire 3 described in FIG. 1 into each of the needle catheters of samples S1 to S3.(b4) The surgeon delivered the needle catheter 2 of sample S1 within the delivery catheter 1 and evaluated the passability of sample S1 within the curved delivery catheter 1. The surgeon delivered the needle catheter of sample S2 within the delivery catheter 1 and evaluated the passability of sample S2 within the curved delivery catheter 1. The surgeon delivered the needle catheter of sample S3 within the delivery catheter 1 and evaluated the passability of sample S3 within the curved delivery catheter 1. (b5) The surgeon repeatedly performed steps b3 and b4 on the second to seventh test devices 80 and evaluated the passability of each combination of seven test devices 80 and three samples. Passability refers to the ease with which the needle catheter 2 passes through the curved portion of the delivery catheter 1 placed within a curved blood vessel. In this test, a needle catheter sample was given an A rating if it was able to pass through the curved portion of the delivery catheter 1. When the needle catheter sample could not pass through the curved portion of the delivery catheter 1, it was given a C rating.

[0059] 20 , in sample S1, which has a tip puncture point TP located inside the outer circumferential surface of the main body 210, the passability was rated A for all test devices 80 except for the test device 80 with a curvature radius R of the curvature 803 of 6 mm. In sample S2, which has a tip puncture point located on an imaginary extension of the outer circumferential surface of the main body, the passability was rated A for test devices 80 with a curvature radius R of the curvature 803 of 15 mm or more, but was rated C for test devices 80 with a curvature radius R of the curvature 803 of 10 mm or less. In sample S3, which has a tip puncture point located on an imaginary extension of the outer circumferential surface of the main body, the passability was rated A for test devices 80 with a curvature radius R of the curvature 803 of 20 mm or more, but was rated C for test devices 80 with a curvature radius R of the curvature 803 of 15 mm or less. These test results show that in order to make the needle catheter 2 easy to pass through the curved portion of the delivery catheter 1 placed inside a curved blood vessel, it is preferable that the tip puncture point TP be located inside the outer surface of the main body portion 210.

[0060] As described above, in the needle catheter 2 of this embodiment, the radial position of the sharp tip puncture point TP of the puncture needle 21 is located inside the outer circumferential surface of the main body 210. Therefore, when the needle catheter 2 is moved within the first lumen 1L of the delivery catheter 1 serving as a combined catheter, the tip puncture point TP of the puncture needle 21 is prevented from getting caught on the inner circumferential surface 12i of the first lumen 1L of the delivery catheter 1. As a result, the needle catheter 2 can be moved smoothly within the delivery catheter 1, preventing damage to the delivery catheter 1 and the puncture needle 21. As a result, the difficulty of the drug solution injection treatment procedure can be reduced, and the time required for the drug solution injection treatment procedure can be shortened.

[0061] Furthermore, if the bending width W21 of the puncture needle 21 of the needle catheter 2 is set to be 1.0 mm or more and 10.0 mm or less, it is possible to improve both the deliverability of the needle catheter 2 within the delivery catheter 1 and the protrusion of the puncture needle 21 from the side opening OP of the delivery catheter 1. Furthermore, if the bending width W21 of the puncture needle 21 of the needle catheter 2 is set to be 2.0 mm or more and 5.0 mm or less, it is possible to further improve the deliverability of the needle catheter 2 within the delivery catheter 1 and further improve the protrusion of the puncture needle 21 from the side opening OP of the delivery catheter 1.

[0062] Furthermore, by setting the bending angle θ21 of the puncture needle 21 of the needle catheter 2 to be equal to or greater than 100° and equal to or less than 170°, it is possible to improve both the deliverability of the needle catheter 2 within the delivery catheter 1 and the protrusion of the puncture needle 21 from the side opening OP of the delivery catheter 1. Furthermore, by setting the bending angle θ21 of the puncture needle 21 of the needle catheter 2 to be equal to or greater than 125° and equal to or less than 150°, it is possible to further improve the deliverability of the needle catheter 2 within the delivery catheter 1 and further improve the protrusion of the puncture needle 21 from the side opening OP of the delivery catheter 1.

[0063] Furthermore, the puncture portion 214 of the puncture needle 21 includes a major cutting surface 215, a first surface 216, and a second surface 217, and the tip puncture point TP is the point where the major cutting surface 215, the first surface 216, and the second surface 217 intersect. Therefore, the operator can easily manufacture the puncture needle 21 having the tip puncture point TP whose radial position is inside the outer peripheral surface of the main body 210 by first forming the major cutting surface 215 by cutting the tubular body obliquely and then forming the first surface 216 and the second surface 217 by cutting the side surfaces away from the tip opening 2a.

[0064] 21 is an enlarged view of a puncture needle 21A of a second embodiment. A medical system 1000A of the second embodiment includes a needle catheter 2A instead of the needle catheter 2 described in the first embodiment. The needle catheter 2A includes a puncture needle 21A instead of the puncture needle 21 described in the first embodiment.

[0065] As shown in FIG. 21 , the puncture needle 21A has, from the base end to the tip end, a first straight portion 211, a curved portion 213, and a puncturing portion 214. The main body 210A of the puncture needle 21A does not have the second straight portion 212 described in the first embodiment. The method for determining the bending width of the puncture needle 21A is the same as in the first embodiment. The bending angle θ21A of the puncture needle 21A is the obtuse angle between the imaginary extension lines VL211 and VL213. The imaginary extension line VL213 is the outer imaginary extension line of the outer edge of the curved portion 213 in a side view that allows the curved shape of the curved portion 213 to be confirmed. The bending width value, bending angle value, and position of the tip puncturing point TP of the puncture needle 21A are the same as in the first embodiment.

[0066] As described above, the configuration of the puncture needle 21A can be modified in various ways, and it may be configured without the second straight portion 212. The puncture needle 21A may be configured without the first straight portion 211, together with or instead of the second straight portion 212. The needle catheter 2A of the second embodiment can also achieve the same effects as the first embodiment.

[0067] <Third Embodiment> Figure 22 is an enlarged view of the tip of a puncture needle 21B of the third embodiment. In Figure 22, the inner cavity of the puncture needle 21B, which constitutes part of the second lumen 2L, is shown by a dashed line. A medical system 1000B of the third embodiment includes a needle catheter 2B instead of the needle catheter 2 described in the first embodiment. The needle catheter 2B includes a puncture needle 21B instead of the puncture needle 21 described in the first embodiment. The shape of the tip of the puncture needle 21B differs from that of the first embodiment.

[0068] The puncture needle 21B has a puncture portion 214B instead of the puncture portion 214. The puncture portion 214B has only a major cutting edge and does not include the first surface 216 and the second surface 217 described in the first embodiment. The major cutting edge of the puncture portion 214B is a single flat surface. The puncture needle 21B has a tip puncture point TPB instead of the tip puncture point TP. The tip portion 21a of the puncture needle 21B is curved toward the imaginary extension line VL212b. Due to the curvature of the tip portion 21a, the position of the tip puncture point TPB in the radial direction of the puncture needle 21B is inside both the imaginary extension line VL212a and the imaginary extension line VL212b. In other words, it can be said that the position of the tip puncture point TPB in the radial direction of the puncture needle 21B is located inside the outer circumferential surface of the main body 210.

[0069] As described above, the configuration of the puncture needle 21B can be modified in various ways, and the tip puncture point TPB may be positioned inside the outer circumferential surface of the main body 210 by curving the tip 21a of the puncture needle 21B. The needle catheter 2B of the third embodiment can also achieve the same effects as the first embodiment.

[0070] <Fourth embodiment> Figure 23 is an enlarged view of the tip of a puncture needle 21C of the fourth embodiment. Figure 24 is a perspective view of the puncture needle 21C of the fourth embodiment. In Figure 23, the inner cavity of the puncture needle 21C, which constitutes part of the second lumen 2L, is shown by a dashed line. The shape of the tip of the puncture needle 21C differs from that of the first embodiment. A medical system 1000C of the fourth embodiment includes a needle catheter 2C instead of the needle catheter 2 described in the first embodiment. The needle catheter 2C includes a puncture needle 21C instead of the puncture needle 21 described in the first embodiment. The shape of the tip of the puncture needle 21C differs from that of the first embodiment.

[0071] The puncture needle 21C has a puncture portion 214C instead of the puncture portion 214. The puncture portion 214C has only a major cutting edge 215 and does not include the first surface 216 and the second surface 217 described in the first embodiment. As shown in FIG. 24 , the major cutting edge 215C is a curved surface. As shown in FIG. 23 , the tip portion 214Ca of the puncture portion 214C is curved toward the imaginary extension line VL212b. Due to the curvature of the tip portion 214Ca, the position of the tip puncture point TPC in the radial direction of the puncture needle 21C is located inside both the imaginary extension line VL212a and the imaginary extension line VL212b. In other words, it can be said that the position of the tip puncture point TPC in the radial direction of the puncture needle 21B is located inside the outer circumferential surface of the main body 210.

[0072] In this way, the configuration of the puncture needle 21C can be modified in various ways, and the tip puncture point TPC may be positioned inside the outer peripheral surface of the main body 210 by curving the tip 214Ca of the puncture section 214C. The needle catheter 2C of the fourth embodiment can also achieve the same effects as the first embodiment.

[0073] <Modifications of this embodiment> The present disclosure is not limited to the above-described embodiment, and can be implemented in various forms without departing from the gist thereof. For example, the following modifications are also possible.

[0074] [Variation 1] In the first to fourth embodiments described above, one example of the configuration of the medical systems 1000, 1000A to 1000C has been shown. The configuration of the medical systems 1000, 1000A to 1000C can be modified in various ways. For example, the stylet wire 3 may be omitted. For example, the medicinal solution 50 may be omitted. For example, the medical system 1000 may be configured to include other devices not described above. Examples of other devices include the guiding catheter 4, a balloon catheter, and a syringe.

[0075] [Variation 2] The first to fourth embodiments described above show one example of the configuration of the delivery catheter 1. The configuration of the delivery catheter 1 can be modified in various ways. For example, the first shaft 12 may not have a distal shaft 12D and a proximal shaft 12P, and may have the same configuration from the distal end to the proximal end. For example, the delivery catheter 1 may not have the marker M. For example, the marker M may have a shape that does not surround the periphery of the side opening OP, such as a simple annular shape.

[0076] [Variation 3] In the first to fourth embodiments, one example of the configuration of the needle catheters 2, 2A to 2C is shown. The configuration of the needle catheters 2, 2A to 2C can be modified in various ways. For example, the needle catheter 2 may be configured by omitting some of the above-described components. For example, the needle catheter 2 may have additional components not described above. For example, the needle catheter 2 may be configured to have multiple lumens other than the second lumen 2L. For example, the second shaft 22 may be configured by omitting at least some of the coil 221, the tube 222, and the shaft 223. For example, the second shaft 22 may not have a distal shaft 22D and a distal shaft 22D, and may have the same configuration from the distal end to the proximal end. For example, the needle catheter 2 may not have a needle marker 24.

[0077] [Variation 4] In the first to fourth embodiments described above, one example of the configuration of the puncture needles 21, 21A to 21C is shown. Various modifications are possible to the configuration of the puncture needles 21, 21A to 21C. For example, the bending width W21 of the puncture needle 21 may be smaller than 1.0 mm. For example, the bending width W21 of the puncture needle 21 may be larger than 10.0 mm. For example, the bending angle θ21 of the puncture needle 21 may be smaller than 100°. For example, the bending angle θ21 of the puncture needle 21 may be larger than 170°.

[0078] [Variation 5] The first to fourth embodiments described above illustrate an example of a surgical method for drug solution injection therapy. The surgical method for drug solution injection therapy can be modified in various ways. For example, the surgeon may use a balloon catheter together with the delivery catheter 1. In this case, the surgeon places the balloon catheter near the side opening of the delivery catheter 1. The surgeon fixes the delivery catheter 1 by inflating the balloon before puncturing with the puncture needle 21, allowing for smooth puncture with the puncture needle 21. For example, the surgeon may inject drug solution 50 into the connector 29 using an injection device other than a syringe. For example, the surgeon may perform additional procedures not described above in the surgical method for drug solution injection therapy. For example, the surgeon may perform PCI before or after the above-described procedures.

[0079] [Variation 6] The configurations of the first to fourth embodiments and the configurations of variations 1 to 5 may be combined as appropriate. For example, the puncturing section 214B described in the third embodiment may be provided in a configuration that does not have the second straight section 212 described in the second embodiment. For example, the puncturing section 214C described in the fourth embodiment may be provided in a configuration that does not have the second straight section 212 described in the second embodiment. The shape of the puncturing section of the puncture needle 21 is not limited to the specific examples described in the third and fourth embodiments, and various modifications are possible.

[0080] This aspect has been described above based on embodiments and modifications. The above-described embodiments of the aspect are intended to facilitate understanding of this aspect and are not intended to limit this aspect. This aspect may be modified or improved without departing from the spirit and scope of the claims, and equivalents thereof are included in this aspect. If a technical feature is not described as essential in this specification, it may be deleted as appropriate.

Claims

1. A needle catheter (2, 2A to 2C) comprising: a hollow puncture needle (21, 21A to 21C) having a curved main body (210, 210A); and a puncture portion (214, 214B, 214C) provided distally of the main body (210, 210A), the puncture portion having a sharp distal puncture point (TP, TPB, TPC), the radial position of the distal puncture point (TP, TPB, TPC) being located more inward than the outer peripheral surface of the main body (210, 210A); and a shaft (22) positioned proximal to the puncture needle (21, 21A to 21C).

2. A needle catheter (2, 2A to 2C) according to claim 1, wherein the main body (210, 210A) includes a curved curved portion (213) and a linear first straight portion (211) located closer to the base end than the curved portion (213), and when the bending width is defined as the distance from the tip puncture point (TP, TPB, TPC) to one of the imaginary extension lines of the outer edge of the first straight portion (211) that is farther from the tip puncture point (TP, TPB, TPC) in a side view in which the curved shape of the curved portion (213) can be seen, the bending width is 1.0 mm or more and 10.0 mm or less.

3. A needle catheter (2, 2A to 2C) according to claim 2, wherein the bending width is 2.0 mm or more and 5.0 mm or less.

4. A needle catheter (2, 2A-2C) according to any one of claims 1 to 3, wherein the main body (210, 210A) includes a curved curved portion (213), a linear first straight portion (211) located closer to the base end than the curved portion (213), and a linear second straight portion (212) located closer to the tip end than the curved portion (213), and wherein, in a side view in which the curved shape of the curved portion (213) can be seen, when the obtuse angle formed by an imaginary extension line of the outer edge of the first straight portion (211) and an imaginary extension line of the outer edge of the second straight portion (212) is defined as the bending angle, the bending angle is equal to or greater than 100° and equal to or less than 170°.

5. A needle catheter (2, 2A to 2C) according to claim 4, wherein the bending angle is 125° or more and 150° or less.

6. A needle catheter (2, 2A) according to any one of claims 1 to 5, wherein the puncture portion (214) includes a main cutting edge surface (215) facing a tip opening (2a) provided at the tip of the puncture needle (21, 21A), a first surface (216) formed at a position away from the tip opening (2a), and a second surface (217) formed at a position away from the tip opening (2a), and the tip puncture point (TP) is the point where the main cutting edge surface (215), the first surface (216), and the second surface (217) intersect.

Images