Medical connector, catheter, and needle catheter

Abstract

This medical connector comprises: a base section having a first through-hole for inserting a first medical device; an intermediate section having a second through-hole connected to the first through-hole, the intermediate part further having, on the inner peripheral surface of the second through-hole, a first portion in which the inner diameter decreases from the base end side toward a tip side, and a second portion that is connected to the tip side of the first portion and in which the inner diameter of the second portion gradually becomes smaller than the inner diameter of the first portion from the base side toward the tip side; and a tip section that has a third through-hole connected to the second through-hole, the third through-hole being for inserting a second medical device.

Description

Medical connector, catheter, and needle catheter

[0001] The present disclosure relates to medical connectors, catheters, and needle catheters.

[0002] Regenerative treatment methods are known that regenerate cardiomyocytes whose function has been impaired by myocardial infarction or the like. For example, Patent Document 1 discloses a treatment method in which cardiomyocytes are prepared in a sheet form outside the body and the cell sheet is attached to the heart to promote cardiomyocyte regeneration. Because the heart is constantly beating, it is difficult to stably attach a cell sheet to the heart for an extended period of time. Therefore, a treatment method that promotes cardiomyocyte regeneration by injecting a medicinal solution into cardiomyocytes is expected. This treatment method will hereinafter be referred to as "medicinal solution injection therapy." In medicinal solution injection therapy, a medicinal solution to promote cardiomyocyte regeneration is injected into the myocardium through at least one of the coronary artery and coronary vein.

[0003] For example, Patent Document 2 discloses a drug solution injection catheter that has a catheter body and a needle-shaped tube with a sharp needle at the tip, and injects a predetermined drug solution into a lesion through the needle-shaped tube. For example, Patent Document 3 discloses a catheter connector that includes a connector body, an elastic member, and a screw member.

[0004] Japanese Patent No. 5572138 Japanese Patent No. 4229621 Japanese Patent Application Laid-Open No. 2013-022255

[0005] During drug solution injection therapy, the surgeon punctures the treatment target site with a puncture needle and then pushes the plunger of a syringe attached to the needle catheter connector. The drug solution ejected from the syringe passes through the internal space of the needle catheter connector and the lumen of the needle catheter shaft, and is then injected into the treatment target site through the puncture needle at the tip of the needle catheter. Therefore, after the surgeon fully pushes the syringe plunger, some of the drug solution remains in the internal space of the connector without reaching the treatment target site. Because the drug solution injected into cardiomyocytes contains active ingredients, it is preferable that it be injected into the cells without waste. The connectors described in Patent Documents 2 and 3 do not address the issue of reducing the amount of drug solution remaining in the connector. Therefore, the connectors described in Patent Documents 2 and 3 have a problem in that a large amount of drug solution remains inside the connector after the drug solution injection therapy procedure is completed due to the large internal space of the connector.

[0006] These problems are not limited to drug solution injection therapy that promotes the regeneration of cardiomyocytes, but are common to all percutaneous procedures using any drug solution. These problems are not limited to needle catheters, but also apply to all catheters with connectors. These problems are not limited to the vascular system, but are common to all catheters inserted into biological lumens, such as the lymphatic system, biliary system, urinary system, respiratory system, digestive system, secretory glands, and reproductive organs.

[0007] The present disclosure has been made to solve at least part of the above-mentioned problems, and can be realized in the following aspects.

[0008] According to one aspect of the present disclosure, there is provided a medical connector comprising: a proximal end portion having a first through hole for insertion of a first medical device; an intermediate portion having a second through hole connected to the first through hole, the intermediate portion including a first section on an inner circumferential surface of the second through hole whose inner diameter decreases from the proximal end to the distal end; and a second section connected to the distal end of the first section, the second section having an inner diameter that gradually decreases from the proximal end to the distal end compared to the inner diameter of the first section; and a distal end portion having a third through hole connected to the second through hole for insertion of a second medical device.

[0009] The present disclosure can be realized in various forms, such as a medical connector, a catheter having a medical connector, a needle catheter having a medical connector, a catheter system including these catheters or needle catheters, and a method of manufacturing these.

[0010] 5 is an explanatory diagram illustrating the configuration of a needle catheter. FIG. 1 is a cross-sectional view taken along line A1-A1 of FIG. 1. FIG. 1 is a cross-sectional view taken along line A2-A2 of FIG. 1. FIG. 1 is a cross-sectional view taken along line A3-A3 of FIG. 1. FIG. 1 is an enlarged view of a connector of a needle catheter. FIG. 2 is a longitudinal cross-sectional view of the connector. FIG. 3 is a longitudinal cross-sectional view of the connector with a shaft attached. FIG. 5 is a cross-sectional view taken along line B1-B1 of FIG. 5. FIG. 5 is a cross-sectional view taken along line B2-B2 of FIG. 5. FIG. 6 is a diagram illustrating the volumes of a first through-hole and a second through-hole. FIG. 7 is an explanatory diagram showing a heart. FIG. 8 is an explanatory diagram showing a state in which a syringe is attached to a needle catheter. FIG. 9 is an explanatory diagram showing a state in which a myocardium is punctured using a needle catheter. FIG. 10 is an explanatory diagram showing a state in which a medicinal solution is injected into a needle catheter. FIG. 11 is a longitudinal cross-sectional view of a connector of a second embodiment. FIG. 12 is an explanatory diagram showing a state in which a syringe is attached to a needle catheter. FIG. 13 is a longitudinal cross-sectional view of a connector of a third embodiment. FIG. 14 is a longitudinal cross-sectional view of a connector of a fourth embodiment. FIG. 15 is a longitudinal cross-sectional view of a connector of a fifth embodiment. FIG. 16 is a longitudinal cross-sectional view of a connector of a sixth embodiment. FIG. 17 is an explanatory diagram illustrating the configuration of a catheter of a seventh embodiment.

[0011] First Embodiment Fig. 1 is an explanatory diagram illustrating the configuration of a needle catheter 2. The needle catheter 2 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 a liquid into body tissue. Hereinafter, a drug solution injection therapy will be illustrated as an example of a specific application of the needle catheter 2. Drug solution injection therapy refers to a treatment method that promotes the regeneration of cardiomyocytes by injecting a drug solution containing therapeutic cells into the myocardium through at least one of a coronary artery and a coronary vein. The target site of drug solution injection therapy is also referred to as the "treatment target site."

[0012] For ease of explanation, FIG. 1 includes some parts in which the relative size ratios of the components are different from the actual ones. FIG. 1 includes some exaggerated views of the components. FIG. 1 illustrates mutually orthogonal X, Y, and Z axes. The X axis corresponds to the longitudinal direction of the needle catheter 2 and the connector 29. The X axis is also referred to as the axial direction. The Y axis corresponds to the height direction of the needle catheter 2 and the connector 29. The Z axis corresponds to the width direction of the needle catheter 2 and the connector 29. The left side of FIG. 1 is referred to as the "distal side" of each device and each component, and the right side of FIG. 1 is referred to as the "proximal side" of each device and each 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 each component, the end located on the distal side is referred to as the "distal end." Of the two longitudinal ends of each device and each component, the other end located on the proximal side is referred to as the "proximal end." The distal end and its vicinity are referred to as the "distal portion." The base end and its vicinity are referred to as the "base end portion." The tip end side is inserted into the living body, and the base end side is manipulated 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 means roughly constant, and allow for variations due to manufacturing errors, etc.

[0013] The needle catheter 2 includes a puncture needle 21, a shaft 22, a needle marker 24, and a connector 29. The needle catheter 2 is a single-lumen catheter having only one lumen 2L. The puncture needle 21 is fixed to the tip of the needle catheter 2. The connector 29 is also called a "medical connector."

[0014] Fig. 2 is a cross-sectional view taken along line A1-A1 in Fig. 1. Fig. 3 is a cross-sectional view taken along line A2-A2 in Fig. 1. Fig. 4 is a cross-sectional view taken along line A3-A3 in Fig. 1. In Figs. 2 to 4, 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 shaft 22.

[0015] The puncture needle 21 is the most distal portion of the needle catheter 2. The puncture needle 21 is a hollow puncture needle attached to the tip of the shaft 22. The puncture needle 21 is also simply referred to as a "needle." The outer diameter of the puncture needle 21 gradually decreases from the base end toward the tip end. The tip end of the puncture needle 21 has a sharp shape to facilitate puncturing body tissue. As shown in FIG. 2, the center of the puncture needle 21 coincides with the axis O at the base end. The tip end of the puncture needle 21 has a curved shape that is curved in a specific direction. In the illustrated example, the puncture needle 21 is curved in the -Y axis direction. The curved portion of the puncture needle 21 is also referred to as a curved portion. Because the puncture needle 21 has a curved portion, the center of the puncture needle 21 is inclined with respect to the axis O at the tip end of the puncture needle 21, as shown in FIG. 1.

[0016] The puncture needle 21 can be made of a metal having shape memory properties. Examples of metals having shape memory properties include nickel-titanium alloys and CuZnAl alloys. 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. The inner cavity of the puncture needle 21 forms part of the lumen 2L. A tip opening 2a is formed at the tip of the puncture needle 21. The tip opening 2a is an opening used to discharge the medicinal solution when injecting the medicinal solution using the needle catheter 2. The puncture needle 21 may be formed integrally with the shaft 22.

[0017] The shaft 22 is a tubular body having an internal lumen 2L and an elongated outer shape. The shaft 22 includes a distal shaft 22D and a distal shaft 22P. A radiopaque needle marker 24 is provided at the tip of the distal shaft 22D. The needle marker 24 is a mark that allows the surgeon to confirm the position of the puncture needle 21 under X-ray images. 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.

[0018] 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. 3 , the distal shaft 22D has a coil 221 and a tube 222.

[0019] The tube 222 maintains the liquid-tightness of the 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 formed from a resin with excellent chemical resistance, for example, a polyimide resin.

[0020] The coil 221 provides a predetermined rigidity and flexibility to the shaft 22 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 a plurality of wires in multiple strands. 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.

[0021] 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. 1, 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.

[0022] 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. 4, 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. 3. The tube 222 is the same member as the tube 222 described in Fig. 3.

[0023] 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.

[0024] 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. 1 , 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.

[0025] As shown by the dashed lines in Figure 1, the puncture needle 21, the shaft 22, and the connector 29 have a lumen 2L formed in them along the longitudinal direction of the needle catheter 2, passing through the interior of each part. The lumen 2L is a lumen for passing a medicinal solution. The inner diameter Φ2L of the lumen 2L may be determined arbitrarily. The tip of the lumen 2L communicates with the outside through a tip opening 2a. The base end of the lumen 2L communicates with the outside through a base opening 2b.

[0026] FIG. 5 is an enlarged view of the connector 29 of the needle catheter 2. The connector 29 is attached to the proximal end of the shaft 22 and makes it easier for the surgeon to grasp the device. The connector 29 is also used by the surgeon to introduce a medicinal solution into the lumen 2L. The connector 29 is a substantially cylindrical member provided with a pair of wings. The connector 29 can be formed from a known resin material. 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 another device into the needle catheter 2. An example of the other device is a syringe for supplying a medicinal solution to the needle catheter 2. In addition to the syringe, a stylet wire may also be used as the other device. The stylet wire is a guide wire inserted into the lumen 2L of the needle catheter 2.

[0027] Figure 6 is a longitudinal cross-sectional view of the connector 29. Figure 7 is a longitudinal cross-sectional view of the connector 29 to which the shaft 22 is attached. The connector 29 of the needle catheter 2 will be described using Figures 5 to 7. As shown in Figure 5, the connector 29 includes a first main body portion 294, a second main body portion 295, wing portions 296, a first flange portion 297, and a second flange portion 298.

[0028] The first main body portion 294 is a portion having a cylindrical outer shape and is disposed at the most distal end of the connector 29. As shown in FIG. 5, a wing portion 296 is provided in the central portion of the first main body portion 294. The wing portion 296 has a wing protruding in the +Y axis direction and a wing protruding in the −Y axis direction. The second main body portion 295 is a portion having a cylindrical outer shape and is disposed closer to the proximal end than the first main body portion 294. The first flange portion 297 is a protruding portion disposed at the distal end of the second main body portion 295. As shown in FIG. 6, the first flange portion 297 is an annular portion that protrudes outward in the circumferential direction. The second flange portion 298 is a protruding portion disposed at the proximal end of the second main body portion 295. As shown in FIG. 6, the second flange portion 298 is an annular portion that protrudes outward in the circumferential direction. 6, the first body portion 294, the second body portion 295, the blade portion 296, the first flange portion 297, and the second flange portion 298 are integrally configured. The first body portion 294, the second body portion 295, the blade portion 296, the first flange portion 297, and the second flange portion 298 may each be formed as an individual member.

[0029] 6, a first through hole TH1, a second through hole TH2, and a third through hole TH3 are formed inside the connector 29 from the base end toward the tip end. The second through hole TH2 is connected to the first through hole TH1. The third through hole TH3 is connected to the second through hole TH2.

[0030] In the illustrated example, the first through hole TH1 is a section from the base end of the first flange 297 to the base end of the second flange 298. The portion of the connector 29 where the first through hole TH1 is formed is also referred to as the base end 293. The diameter of the first through hole TH1 becomes slightly smaller from the base end side to the tip end side. The diameter of the first through hole TH1 may be constant from the base end side to the tip end side. A first medical device is inserted into the first through hole TH1. An example of the first medical device is a syringe 8, which will be described later.

[0031] In the illustrated example, the second through hole TH2 is a section from the base end of the first main body portion 294 to the base end of the first flange portion 297. The portion of the connector 29 where the second through hole TH2 is formed is also referred to as an intermediate portion 292. The intermediate portion 292 has a first portion P1 and a second portion P2. The diameter of the second through hole TH2 in the first portion P1 gradually decreases from the base end toward the tip end. The diameter of the second through hole TH2 in the second portion P2 gradually decreases from the base end toward the tip end. The inner diameter of the second portion P2 decreases more gradually than the inner diameter of the first portion P1. The inner diameter of the tip of the first portion P1 is equal to the inner diameter of the base end of the second portion P2. By having such a first portion P1 and second portion P2, the second through hole TH2 has a trumpet shape facing the base end. In the illustrated example, the length of the second portion P2 in the longitudinal direction of the connector 29 is longer than the length of the first portion P1.

[0032] As shown in Fig. 7, the inner diameter ΦTH2 of the base end of the intermediate portion 292 is the same as the inner diameter ΦTH1 of the tip of the base end 293. The inner diameter ΦTH2 of the base end of the second through hole TH2 is the same as the inner diameter ΦTH1 of the tip of the first through hole TH1. Therefore, in the example of Fig. 6, there is no step between the intermediate portion 292 and the base end 293 in the internal space of the connector 29. There is no step between the second through hole TH2 and the third through hole TH3. In this embodiment, the "step" refers to a vertical surface on the inner circumferential surface side of the connector 29 in the longitudinal cross section shown in Fig. 6, and does not include an inclined surface such as the first portion P1 of the intermediate portion 292.

[0033] In the illustrated example, the third through hole TH3 is a section from the tip of the first main body portion 294 to the base end of the first main body portion 294. The portion of the connector 29 where the third through hole TH3 is formed is also referred to as the tip portion 291. The tip portion 291 has a base end portion Pa, an intermediate portion Pb, and a tip end portion Pc. The base end portion Pa is a portion of the inner circumferential surface of the third through hole TH3 that has a substantially constant inner diameter. The inner diameter of the base end of the base end portion Pa is equal to the inner diameter of the tip of the second portion P2. The intermediate portion Pb is a portion of the inner circumferential surface of the third through hole TH3 that has a substantially constant inner diameter that is larger than that of the base end portion Pa. A step is formed between the intermediate portion Pb and the base end portion Pa. The diameter of the third through hole TH3 at the tip end portion Pc gradually increases from the base end side toward the tip end side. The inner diameter of the base end of the distal portion Pc is equal to the inner diameter of the intermediate portion Pb. In the illustrated example, the length of the proximal portion Pa is the shortest in the longitudinal direction of the connector 29. The length of the distal portion Pc is the longest in the longitudinal direction of the connector 29. A second medical device is inserted into the third through hole TH3. An example of the second medical device is the shaft 22 described in FIG. 7.

[0034] 6 , in the longitudinal direction of the connector 29, the length L292 of the intermediate portion 292 is shorter than the length L291 of the tip portion 291. In the longitudinal direction of the connector 29, the length L292 of the intermediate portion 292 is shorter than the length L293 of the base end portion 293. In the longitudinal direction of the connector 29, the length L293 of the base end portion 293 is shorter than the length L291 of the tip portion 291. The length L293 of the base end portion 293 may be longer than the length L291 of the tip portion 291. The length L293 of the base end portion 293 and the length L291 of the tip portion 291 may be the same.

[0035] 7, the proximal end of the shaft 22 is inserted into the third through-hole TH3 of the connector 29 and fixed thereto by a bonding agent 28. As a result, the first through-hole TH1 and the second through-hole TH2 form part of the lumen 2L of the needle catheter 2.

[0036] Fig. 8 is a cross-sectional view taken along line B1-B1 in Fig. 5. Fig. 9 is a cross-sectional view taken along line B2-B2 in Fig. 5. As shown in Fig. 8, the internal space of the intermediate portion 292 of the connector 29 has a circular cross-section. The internal space of the second through-hole TH2 has a circular cross-section. As shown in Fig. 9, the internal space of the base end portion 293 of the connector 29 has a circular cross-section. The internal space of the first through-hole TH1 has a circular cross-section.

[0037] FIG. 10 is a diagram illustrating the volumes of the first through hole TH1 and the second through hole TH2. FIG. 10 is a diagram illustrating the longitudinal section VTH1 of the first through hole TH1 and the longitudinal section VHT2 of the second through hole TH2, which are superimposed on the longitudinal section of the connector 29 shown in FIG. 6. As described in FIGS. 8 and 9, both the first through hole TH1 and the second through hole TH2 have circular cross sections. As shown in FIG. 10, the area of ​​the longitudinal section VHT2 of the second through hole TH2 is smaller than the area of ​​the longitudinal section VTH1 of the first through hole TH1. Therefore, in the connector 29, the volume of the second through hole TH2 is smaller than the volume of the first through hole TH1. The volume of the internal space of the intermediate portion 292 is smaller than the volume of the internal space of the base end portion 293. In this embodiment, the volume of the internal space of the intermediate portion 292 is approximately 30 mm. ２ is.

[0038] FIG. 11 is an explanatory diagram showing a heart. FIG. 11 shows a heart 90, a guiding catheter 4 inserted into the heart 90, a delivery catheter 1, and a needle catheter 2. FIG. 12 is an explanatory diagram showing a state in which a syringe 8 is attached to the needle catheter 2. FIG. 13 is an explanatory diagram showing a state in which a myocardium 96 is punctured using the needle catheter 2. FIG. 14 is an explanatory diagram showing a state in which a medicinal solution 50 is injected into the needle catheter 2. Hereinafter, a surgical method for medicinal solution injection therapy will be described using FIGS. 11 to 14. In the following example, a procedure via the coronary artery will be illustrated. A procedure via the coronary vein may also be used. This medicinal solution injection therapy may be performed simultaneously with a percutaneous coronary intervention procedure, or may be performed independently.

[0039] An operator uses delivery catheter 1 to deliver needle catheter 2 to a treatment site during a drug solution injection treatment procedure. As shown in Figure 13, delivery catheter 1 is a catheter with a single lumen for inserting needle catheter 2. Delivery catheter 1 has a shaft and a distal tip. A side opening 1c is formed on the side of the distal end of the shaft of delivery catheter 1, connecting the lumen of delivery catheter 1 to the outside. In Figure 13, both delivery catheter 1 and needle catheter 2 inside the lumen of delivery catheter 1 are shown by solid lines.

[0040] Returning to FIG. 11 , the explanation will continue. For example, the surgeon can perform the procedure for drug solution injection treatment by the following steps a1 to a11. (a1) The surgeon inserts a work horse wire from the patient's wrist or thigh. The surgeon delivers the work horse wire to the vicinity of the treatment target site in the left coronary artery 94. The work horse wire is a guide wire used for delivery. (a2) The surgeon inserts the work horse wire from the tip of the guiding catheter 4 and delivers the guiding catheter 4 along the work horse wire to the entrance of the left coronary artery 94. (a3) ​​The surgeon inserts the work horse wire from the tip of the delivery catheter 1. The surgeon pushes the delivery catheter 1 along the work horse wire 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 and delivers it until the side opening 1c of the delivery catheter 1 reaches a position in the left coronary artery 94 near the treatment target site. At this time, the surgeon adjusts the circumferential orientation of the delivery catheter 1 so that the side opening 1c of the delivery catheter 1 is positioned on the myocardium 96 side, as shown in FIG. 13 . The surgeon then removes the workpiece wire from the delivery catheter 1. (a5) The surgeon inserts the needle catheter 2 into the delivery catheter 1. At this time, the surgeon gently curves the puncture needle 21 of the needle catheter 2 until the length of the puncture needle 21 in the curved direction is equal to or less than the inner diameter of the delivery catheter 1. The surgeon pushes the needle catheter 2 toward the distal end inside the delivery catheter 1. In step a5, the surgeon may use the needle catheter 2 with a stylet wire inserted. In this case, prior to step a5, the surgeon inserts a stylet wire into needle catheter 2 and projects the tip of the stylet wire from tip opening 2a. In this way, the tip of puncture needle 21 is protected by the stylet wire, thereby suppressing damage to the inner surface of delivery catheter 1 and damage to puncture needle 21 that may occur during delivery of needle catheter 2.(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 1c of the delivery catheter 1. After delivering the needle catheter 2, if a stylet wire is used, the surgeon removes the stylet wire from the needle catheter 2. (a7) The surgeon injects the medicinal solution 50 into the needle catheter 2. The surgeon prepares a syringe 8 filled with the medicinal solution 50. As shown in FIG. 12 , the surgeon inserts the nozzle 81 of the syringe 8 into the first through-hole TH1 of the connector 29 of the needle catheter 2. The surgeon pushes in the plunger of the syringe 8. This supplies the medicinal solution 50 in the syringe 8 to the lumen 2L of the needle catheter 2. The surgeon continues supplying the medicinal solution 50 until the 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. 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 1c 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 82 of the syringe 8 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 pulls the needle catheter 2 toward the operator. This causes the puncture needle 21 of the needle catheter 2 to be withdrawn from the myocardium 96. The surgeon then further pulls the needle catheter 2 toward the operator, thereby storing the puncture needle 21 of the needle catheter 2 within the lumen 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 1c 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.

[0041] In this way, in 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, thereby improving the therapeutic effect of the drug solution 50 compared to when the drug solution 50 is administered by other means.

[0042] After the drug solution injection treatment is completed and the syringe 8 is removed from the needle catheter 2, the drug solution 50 that was not completely pushed out by the plunger 82 remains inside the second through-hole TH2, which is indicated by a dashed circle in FIG. 14 . In the needle catheter 2 of this embodiment, the intermediate portion 292 of the connector 29 has a first portion P1 and a second portion P2 whose inner diameters decrease from the base end to the tip end. This reduces the volume of the second through-hole TH2, which becomes dead space, and reduces the amount of drug solution 50 remaining in the second through-hole TH2 after the drug solution injection treatment procedure. Reducing the volume of the second through-hole TH2 also prevents the therapeutic particles 52, 53, and 54 in the drug solution 50 from settling in the second through-hole TH2.

[0043] The connector 29 has a second portion P2 distal to the first portion P1, whose inner diameter gradually decreases from the base end to the distal end compared to the first portion P1. This allows the pressure of the medicinal solution 50 injected from the syringe 8 serving as the first medical device to be dispersed during injection. Specifically, the taper angle of the second portion P2 on the inner circumferential surface of the second through-hole TH2 is smaller than that of the first portion P1, resulting in a fluid pressure loss at the transition between the first portion P1 and the second portion P2. Therefore, when the first portion P1, through which the medicinal solution 50 is supplied, is defined as the upstream side and the second portion P2 is defined as the downstream side, the pressure loss at the transition reduces the fluid pressure downstream. In other words, the inflow pressure of the fluid into the shaft 22 can be lower than the injection pressure of the fluid from the syringe 8, allowing the flow rate and flow velocity of the fluid in the lumen 2L of the shaft 22 to be gentle. As a result, even if the surgeon pushes the plunger 82 of the syringe 8 forcefully, the flow rate and flow velocity of the medicinal solution 50 delivered from the connector 29 into the lumen 2L of the shaft 22 can be maintained at a substantially constant level, thereby suppressing damage to the active ingredients in the medicinal solution caused by friction within the lumen 2L and damage to the myocardium 96. As a result, the effectiveness of medicinal solution injection therapy can be improved.

[0044] According to the connector 29 of this embodiment, the volume of the second through hole TH2 is smaller than the volume of the first through hole TH1 for inserting the syringe 8, so that the volume of the dead space can be further reduced. After the medical solution injection treatment procedure, the amount of medical solution 50 remaining in the second through hole TH2 can be further reduced.

[0045] The connector 29 of this embodiment is used to deliver a medicinal solution 50 containing therapeutic particles. The connector 29 reduces the volume of the second through-hole TH2, which becomes dead space, and therefore can prevent particles 52, 53, and 54 in the medicinal solution 50 from settling within the second through-hole TH2. The therapeutic particles contained in the medicinal solution 50 can be at least one of a single cell 52, a cell cluster 53, and an organoid 54, which is a group of single cells or cell clusters.

[0046] According to connector 29 of the present embodiment, the inner diameter ΦTH2 of the base end of intermediate portion 292 is the same as the inner diameter ΦTH1 of the tip of base end portion 293. Therefore, connector 29 can be provided in which there is no step between intermediate portion 292 and base end portion 293 in the internal space of connector 29.

[0047] According to the connector 29 of this embodiment, the length L292 of the intermediate portion 292 is shorter than the length L293 of the base end portion 293, so that the volume of the second through-hole TH2, which becomes dead space, can be further reduced, and the amount of medicinal solution 50 remaining in the second through-hole TH2 after the medicinal solution injection treatment procedure can be further reduced.

[0048] According to the connector 29 of this embodiment, the length L292 of the intermediate portion 292 is shorter than the length L291 of the distal end portion 291, and therefore the volume of the second through-hole TH2 that becomes dead space can be further reduced, thereby further reducing the amount of medicinal solution 50 remaining in the second through-hole TH2 after the medicinal solution injection treatment procedure.

[0049] The needle catheter 2 of this embodiment includes a connector 29, a shaft 22 as a second medical device, and a puncture needle 21 fixed to the tip of the shaft 22. A portion of the base end of the shaft 22 is inserted into the third through-hole TH3 and fixed to the connector 29. This makes it possible to provide a needle catheter 2 that can reduce the amount of medicinal solution 50 remaining in the internal space of the connector 29 after the procedure is completed.

[0050] <Second embodiment> Figure 15 is a longitudinal cross-sectional view of a connector 29A of a second embodiment. Figure 16 is an explanatory view showing the state in which a syringe 8 is attached to a needle catheter 2A. The needle catheter 2A of the second embodiment has a connector 29A instead of the connector 29 described in the first embodiment. The connector 29A has an intermediate portion 292A instead of the intermediate portion 292.

[0051] As shown in FIG. 15 , a second through-hole TH2A is formed inside the intermediate portion 292A. The intermediate portion 292A has a first portion P1A instead of the first portion P1. The diameter of the second through-hole TH2A in the first portion P1A gradually decreases from the base end toward the tip end. The taper angle of the first portion P1A is smaller than the taper angle of the first portion P1 described in the first embodiment. Therefore, the inner diameter ΦTH2A at the base end of the intermediate portion 292A is smaller than the inner diameter ΦTH1 at the tip end of the base end 293. A step portion 299 is formed at the base end of the first portion P1A, between the intermediate portion 292A and the base end 293. The step portion 299 is a vertical surface on the inner circumferential surface of the connector 29A. The vertical surface refers to a surface perpendicular to the longitudinal direction of the connector 29A. The vertical surface refers to a surface extending in the YZ axis direction. The size of the step portion 299 is preferably 0.2 mm or more and 0.8 mm or less. The size of the step portion 299 means the length from one end of the tip of the first through hole TH1 to one end of the base of the second through hole TH2A in the longitudinal cross section shown in Figure 15. The inner diameter of the second portion P2 is gradually reduced more gradually than the inner diameter of the first portion P1A.

[0052] According to the needle catheter 2A of the second embodiment, when the surgeon attaches the syringe 8 to the needle catheter 2A in step a7 of the drug solution injection treatment, the distal end surface 81 a of the cylindrical tip 81 of the syringe 8 abuts against the stepped portion 299 of the connector 29A. This allows the syringe 8 to be securely inserted into the connector 29A. Because the size of the stepped portion 299 is 0.2 mm or more, the distal end surface 81 a of the cylindrical tip 81 of the syringe 8 can be supported by the stepped portion 299. Because the size of the stepped portion 299 is 0.8 mm or less, the stepped portion 299 is positioned outside the inner circumferential surface of the cylindrical tip 81 of the syringe 8, as shown by the dashed circle in FIG. 16 . As a result, the stepped portion 299 is prevented from obstructing the flow path of the drug solution 50.

[0053] As described above, the configuration of the connector 29A can be modified in various ways, and a step 299 may be provided between the intermediate portion 292A and the base end 293. The needle catheter 2A of the second embodiment described above can also achieve the same effects as the first embodiment. The needle catheter 2A of the second embodiment can provide a connector 29 having a step 299 between the intermediate portion 292A and the base end 293 in the internal space of the connector 29A. By abutting the nozzle 81 of the syringe 8 against the step 299, the surgeon can further reduce the amount of medicinal solution 50 remaining in the second through hole TH2A after the medicinal solution injection treatment procedure.

[0054] Third Embodiment Figure 17 is a longitudinal cross-sectional view of a connector 29B of the third embodiment. A needle catheter 2B of the third embodiment includes a connector 29B instead of the connector 29 described in the first embodiment. The connector 29B has an intermediate portion 292B instead of the intermediate portion 292. As shown in Figure 17, a second through-hole TH2B is formed inside the intermediate portion 292B. The intermediate portion 292B has a first portion P1B instead of the first portion P1 and a second portion P2B instead of the second portion P2. The first portion P1B and the second portion P2B differ from the first embodiment only in the lengths in the longitudinal direction of the connector 29B. Specifically, the length of the second portion P2B in the longitudinal direction of the connector 29B is shorter than the length of the first portion P1B.

[0055] As described above, the configuration of the connector 29B can be modified in various ways, and the lengths of the first portion P1B and the second portion P2B can be determined arbitrarily. For example, the length of the second portion P2B in the longitudinal direction of the connector 29B may be the same as the length of the first portion P1B. The needle catheter 2B of the third embodiment described above can also achieve the same effects as the first embodiment.

[0056] <Fourth Embodiment> Figure 18 is a longitudinal cross-sectional view of a connector 29C of the fourth embodiment. A needle catheter 2C of the fourth embodiment includes a connector 29C instead of the connector 29 described in the first embodiment. The connector 29C has a base end 293C instead of the base end 293. As shown in Figure 18, a first through hole TH1C is formed inside the base end 293C. The base end 293C differs from the first embodiment only in its length in the longitudinal direction of the connector 29C. Specifically, the length L293C of the base end 293C in the longitudinal direction of the connector 29C is shorter than the length L292 of the intermediate portion 292. In the connector 29C, the volume of the second through hole TH2 is equal to or greater than the volume of the first through hole TH1C.

[0057] As described above, the configuration of the connector 29C can be modified in various ways, and the length L293C of the base end 293C can be determined arbitrarily. For example, the length L293C of the base end 293C can be the same as the length L292 of the intermediate portion 292. The connector 29C can be configured by omitting at least one of the first flange 297 and the second flange 298. The needle catheter 2C of the fourth embodiment described above can also achieve the same effects as the first embodiment.

[0058] Fifth Embodiment Figure 19 is a longitudinal cross-sectional view of a connector 29D of the fifth embodiment. A needle catheter 2D of the fifth embodiment includes a connector 29D instead of the connector 29 described in the first embodiment. The connector 29D has a distal end portion 291D instead of the distal end portion 291, and does not have a wing portion 296. As shown in Figure 19, a third through hole TH3D is formed inside the distal end portion 291D. The distal end portion 291D differs from the first embodiment only in its length in the longitudinal direction of the connector 29D. Specifically, the length L291D of the distal end portion 291D in the longitudinal direction of the connector 29D is shorter than the length L292 of the intermediate portion 292. In the connector 29C, the volume of the second through hole TH2 is equal to or greater than the volume of the third through hole TH3D.

[0059] As described above, the configuration of the connector 29D can be modified in various ways, and the length L291D of the tip portion 291D can be determined arbitrarily. For example, the length L291D of the tip portion 291D can be the same as the length L292 of the intermediate portion 292. The wing portions 296 can be omitted. The connector 29D can also have wing portions 296 with a different shape than those in the first embodiment. The needle catheter 2D of the fifth embodiment described above can also achieve the same effects as those in the first embodiment.

[0060] <Sixth Embodiment> Figure 20 is a longitudinal cross-sectional view of a connector 29E of the sixth embodiment. A needle catheter 2E of the sixth embodiment includes a connector 29E instead of the connector 29 described in the first embodiment. The connector 29E has a base end 293E instead of the base end 293. As shown in Figure 20, a first through-hole TH1E is formed inside the base end 293E. The first through-hole TH1E has a constant inner diameter from the tip to the base end.

[0061] As described above, the configuration of the connector 29E can be modified in various ways, and the first through-hole TH1E may have a constant inner diameter. Similarly, the third through-hole TH3 of the distal end portion 291 may have a constant inner diameter from the distal end to the proximal end. The needle catheter 2E of the sixth embodiment described above can also achieve the same effects as the first embodiment.

[0062] Seventh Embodiment Figure 21 is an explanatory diagram illustrating the configuration of a catheter 2F of a seventh embodiment. The catheter 2F of the seventh embodiment does not have the puncture needle 21 described in the first embodiment. The catheter 2F targets the inside of a blood vessel, the inside of a biological tube other than a blood vessel, or the inside of an organ as a treatment target site, instead of the myocardium 96. The catheter 2F does not perform puncture with the puncture needle 21, but performs treatment by releasing a medicinal solution 50 from the distal end opening 2a of the catheter 2F toward the treatment target site.

[0063] As described above, the configuration of the catheter 2F can be modified in various ways, and the catheter 2F need not have the puncture needle 21. The shaft 22 can also be modified as appropriate. For example, the shaft 22 may not include at least a portion of the coil 221, the tube 222, and the shaft 223. For example, the shaft 22 may not include the distal shaft 22D and the proximal shaft 22P, and may have the same configuration from the distal end to the proximal end. The catheter 2F of the seventh embodiment described above can also achieve the same effects as the first embodiment.

[0064] <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.

[0065] [Variation 1] In the first to seventh embodiments, the needle catheters 2, 2A to 2E, and the catheter 2F are exemplified. The configurations of the needle catheters 2, 2A to 2E, and the catheter 2F can be modified in various ways. For example, the needle catheters 2 and 2F may be configured by omitting some of the above-described configurations. For example, the needle catheters 2 and 2F may have additional configurations not described above. The needle catheters 2 and 2F may have multiple lumens different from the lumen 2L.

[0066] [Variation 2] In the first to seventh embodiments, one example of the configuration of the connectors 29, 29A to 29E has been described. The configuration of the connectors 29, 29A to 29E can be modified in various ways. For example, the connector 29 may be used to deliver a fluid that does not contain therapeutic particles. For example, the connector 29 may not include at least some of the first main body portion 294, the second main body portion 295, the wing portion 296, the first flange portion 297, and the second flange portion 298. For example, the shape and dimensions of at least some of the first main body portion 294, the second main body portion 295, the wing portion 296, the first flange portion 297, and the second flange portion 298 may be modified as desired.

[0067] [Variation 3] The first to seventh embodiments described above illustrate one 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 connector 29 using an injection device other than syringe 8. In this case, the injection device corresponds to the first medical device. 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.

[0068] [Modification 4] The configurations of the first to seventh embodiments and the configurations of modifications 1 to 3 may be combined as appropriate. For example, a catheter 2F may be configured having connectors 29A to 29E described in the second to sixth embodiments. For example, the step portion 299 described in the second embodiment may be provided in connectors 29B to 29E described in the third to sixth embodiments. For example, a connector 29 may be configured having at least one of the intermediate portion 292B described in the third embodiment, the base end portion 293C described in the fourth embodiment, the tip portion 291D described in the fifth embodiment, and the base end portion 293E described in the sixth embodiment.

[0069] 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 medical connector (29, 29A-29E) comprising: a proximal end (293, 293C, 293E) having a first through-hole (TH1, TH1C, TH1E) for inserting a first medical device; an intermediate portion (292, 292A, 292B) having a second through hole (TH2, TH2A, TH2B) connected to the first through hole (TH1, TH1C, TH1E), wherein an inner diameter of an inner circumferential surface of the second through hole (TH2, TH2A, TH2B) decreases from a base end side to a tip end side, and a second portion (P2, P2B) connected to the tip end side of the first portion (P1, P1A, P1B), wherein an inner diameter of the second portion (P2, P2B) gradually decreases from the base end side to a tip end side less than an inner diameter of the first portion (P1, P1A, P1B); a third through hole (TH3, TH3D) connected to the second through hole (TH2, TH2A, TH2B), and a tip portion (291, 291D) having the third through hole (TH3, TH3D) for inserting a second medical device.

2. A medical connector (29, 29A, 29B, 29D, 29E) according to claim 1, wherein the volume of the second through-hole (TH2, TH2A, TH2B) is smaller than the volume of the first through-hole (TH1, TH1E).

3. A medical connector (29, 29A to 29E) according to claim 1 or claim 2, wherein the medical connector (29, 29A to 29E) is used to deliver a medicinal solution (50) containing therapeutic particles.

4. A medical connector (29, 29B to 29E) according to any one of claims 1 to 3, wherein the inner diameter of the base end of the intermediate section (292, 292B) is the same as the inner diameter of the tip of the base end section (293, 293C, 293E).

5. A medical connector (29A) according to any one of claims 1 to 3, wherein the inner diameter of the base end of the intermediate section (292A) is smaller than the inner diameter of the tip of the base end section (293, 293C, 293E), and a step section (299) is formed between the intermediate section (292A) and the base end section (293, 293C, 293E).

6. A medical connector (29, 29A, 29B, 29D, 29E) according to any one of claims 1 to 5, wherein the length of the intermediate portion (292, 292A, 292B) in the longitudinal direction of the medical connector (29, 29A, 29B, 29D, 29E) is shorter than the length of the base end portion (293, 293E).

7. A medical connector (29, 29A to 29C, 29E) according to any one of claims 1 to 6, wherein the length of the intermediate portion (292, 292A, 292B) in the longitudinal direction of the medical connector (29, 29A to 29C, 29E) is shorter than the length of the tip portion (291).

8. A catheter (2F) comprising: a medical connector (29, 29A-29E) according to any one of claims 1 to 7; and a shaft (22) as the second medical device, the shaft (22) being fixed to the medical connector (29, 29A-29E) with a portion of its base end inserted into the third through-hole (TH3, TH3D).

9. A needle catheter (2, 2A to 2E) comprising: a catheter (2F) according to claim 8; and a hollow puncture needle (21) fixed to the tip of the shaft.

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