JP7078606B2 - Puncture device and medical device - Google Patents

Description

The present invention relates to a puncture device and a medical device for puncturing a living tissue.

The heart circulates blood by repeatedly contracting and expanding at appropriate timings by passing an electric current through the myocardial tissue called the conduction system. When the generation or transmission of electrical signals flowing through this conduction system becomes abnormal, contraction and expansion cannot be performed at appropriate timings, resulting in arrhythmia.

As a method for treating arrhythmia, a method of ablating and blocking the conduction path of a signal causing arrhythmia by heating or cooling is known. As a device for performing this therapeutic method, a device that can be inserted percutaneously to the left atrium and ablate the conduction path of a signal located at the pulmonary venous opening is known. Such ablation devices are widely used because they are minimally invasive and highly effective.

When performing ablation in the left atrium, a needle is inserted into a thin partition wall called the oviduct of the interatrial septum from the right atrium to make a hole leading from the right atrium to the left atrium. A procedure is required. Trans-septal needles, which are devices for performing this atrial septal puncture, include mechanical needles and radio frequency energy needles.

Before performing an atrial septal puncture, the distal portion of the dilator is usually abutted against the fossa ovalis and the dilator is pressed. As a result, the ovary fossa is pushed toward the left atrium and deformed. After that, the fossa ovalis is punctured with a puncture needle penetrating the dilator, and the dilator is inserted into the punctured hole.

For example, Patent Document 1 describes a device in which a mechanical puncture needle is housed inside a dilator. A puncture needle protruding from the dilator of this device is used to make a hole in the fossa ovalis, and the dilator is inserted into the hole to widen the hole in the fossa ovalis.

U.S. Patent Publication No. 2002/0169377

When the fossa ovalis is punctured by the puncture needle, if the puncture needle moves inside the dilator, the shape such as the curvature of the puncture needle may interfere with the dilator. If the dilator bends due to the movement of the curved portion of the puncture needle, the position where the dilator is in contact with the fossa ovalis may shift, and the puncture position may shift. Further, when the curved portion of the puncture needle moves in the dilator, the sliding resistance is high, so that the operability is low.

The present invention has been made to solve the above-mentioned problems, and an object of the present invention is to provide a puncture device and a medical device capable of puncturing a living tissue in a living body with high position accuracy and improving operability. do.

The puncture device according to the present invention that achieves the above object is a puncture device that is inserted into a tubular elongated body and is used to cauterize biological tissue in a living body to form a hole through the elongated body. A metal puncture site located on the distal side and having conductivity for cauterizing and piercing living tissue, a long proximal shaft located on the proximal side, and the puncture site and the proximal shaft. It has a flexible portion that is located between the puncture portions and a flexible portion whose bending rigidity is lower than the bending rigidity of the puncture portion and the proximal shaft, and the flexible portion is insulated from a support portion having conductivity and made of resin. It has a flexible support and the proximal shaft is made of conductive metal, the proximal shaft, the support and the puncture are electrically connected and the support is. , The flexible support is arranged so as to have a radial penetrating gap between the distal end of the support and the proximal end of the support, the flexible support. It enters the gap so as to fill the gap in the support portion and closes the gap .

The medical device according to the present invention that achieves the above object is a medical device for cauterizing a biological tissue in a living body to form a hole, and is a puncture device for cauterizing and puncturing the biological tissue, and the above-mentioned puncture device. It has a tubular dilator into which the puncture device is inserted and a tubular outer sheath into which the dilator is inserted, wherein the puncture device is located distally and is a conductive metal for puncturing living tissue. A puncture site, a long proximal shaft located on the proximal side, and a position between the puncture site and the proximal shaft, which is lower than the bending rigidity of the puncture site and the proximal shaft. The outer sheath has a flexible portion having a bending rigidity lower than that of the sheath assembly in which the dilator is inserted, and the flexible portion is made of a resin and has an insulating flexible support and a support portion having conductivity. The proximal shaft is made of conductive metal, the proximal shaft, the support and the puncture are electrically connected, and the support is radially connected. The flexible support portion is arranged so as to have a penetrating gap between the distal end portion of the support portion and the proximal side end portion of the support portion, and the flexible support portion is a gap of the support portion. It enters the gap and closes the gap so as to make up for the gap .

In the puncture device and medical device configured as described above, the flexible portion is more flexible than the puncture portion and the proximal shaft, so that the flexible portion interferes with the shape of the elongated body even when inserted into the elongated body. hard. Therefore, when the puncture portion is projected from the long body to the distal side, the shape of the long body is maintained and the target position can be punctured with high position accuracy. Further, since the flexible portion does not easily interfere with the shape of the long body, the sliding resistance when the puncture device is moved inside the long body is reduced. Therefore, the puncture device can be easily inserted into the long body and the operability is improved.

It is a top view which shows the medical device which concerns on embodiment. It is sectional drawing which shows the medical device which concerns on embodiment. It is sectional drawing which shows the state which combined each part of the medical device which concerns on embodiment. It is a partial cross-sectional view which shows the inside of a heart. It is a cross-sectional view showing the state when puncturing with a medical device, (A) is a state where the sheath assembly is inserted into the right atrium along a guide wire, and (B) is a state where the sheath assembly is in contact with the fossa ovalis. (C) shows a state in which the puncture device is inserted into the sheath assembly, and (D) shows a state in which the fossa ovalis is punctured by the puncture portion. It is a cross-sectional view which shows the state when puncturing with a medical device, (A) is the state which inserted the sheath assembly into the hole of the fossa ovalis, (B) is the state which pulled out the puncture device from the sheath assembly, (A). C) shows a state in which a guide wire and an ablation catheter are inserted into the outer sheath. It is a top view which shows the 1st modification of a medical device. It is a top view which shows the 2nd modification of a puncture device. It is a perspective view which shows the 3rd modification of a puncture device. FIG. It is a perspective view which shows the 4th modification of a puncture device. FIG. It is a perspective view which shows the 5th modification of a puncture device. FIG. It is sectional drawing which shows the 6th modification of the puncture device, (A) shows the state before bending a flexible part, (B) shows the state before bending a flexible part.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. The dimensional ratios in the drawings may be exaggerated and differ from the actual ratios for convenience of explanation. In the present specification, the side of the device to be inserted into the blood vessel is referred to as the "distal side", and the hand side to be operated is referred to as the "proximal side".

The medical device 1 according to the embodiment of the present invention is for inserting a needle from the right atrium into the ovary fossa O of the interatrial septum to form a hole leading from the right atrium R to the left atrium L (see FIG. 4). Used. If there is a hole in the oviduct O, ablation catheter inserted percutaneously into the vena cava should be guided to the right atrium R and then inserted into the left atrium L through the hole to ablate around the pulmonary vein opening. Can be done. That is, the medical device 1 is a device for forming an access route for an ablation catheter in the fossa ovalis.

As shown in FIGS. 1 to 3, the medical device 1 has a puncture device 10 for puncturing and a sheath assembly 20 for accommodating the puncture device 10. The puncture device 10 has a long needle portion 30 and an operation portion 60 for gripping and operating. The sheath assembly 20 has a dilator 40 into which the puncture device 10 is inserted and an outer sheath 50 into which the dilator 40 is inserted.

The needle portion 30 is a substantially straight tube for puncturing. The needle portion 30 has a puncture portion 31 located on the distal side, a proximal shaft 33 located on the proximal side, and a flexible portion 32 located between the puncture portion 31 and the proximal shaft 33. .. The proximal shaft 33 is a hollow tube. The proximal portion of the proximal shaft 33 is fixed to the operating portion 60. The distal portion of the proximal shaft 33 is fixed to the flexible portion 32. The proximal shaft 33 has a proximal inner layer 33A made of a conductive metal and an insulating proximal outer layer 33B covering the outer peripheral surface of the proximal inner layer 33A. The proximal inner layer 33A can be connected to the connector 62 of the operation unit 60 to transmit a current to the distal side. The proximal outer layer 33B insulates the proximal inner layer 33A. The proximal shaft 33 does not have to have a two-layer structure. The proximal shaft 33 does not have to be conductive as long as the conductive wire can be arranged inside the proximal shaft 33. The flexural rigidity of the proximal shaft 33 is greater than the flexural rigidity of the sheath assembly 20. Further, the bending rigidity of the proximal shaft 33 is larger than the bending rigidity of the dilator 40 and larger than the bending rigidity of the outer sheath 50.

The puncture portion 31 is a hollow tube with a closed distal end and has an electrode 34 at the distal end. The electrode 34 outputs high frequency energy for making a hole in the fossa ovalis O. The puncture portion 31 has a distal inner layer 31A made of a conductive metal and an insulating distal outer layer 31B covering the outer peripheral surface of the proximal portion of the distal inner layer 31A. The portion of the distal inner layer 31A not covered by the distal outer layer 31B is the electrode 34. The electrode 34 comes into contact with the living tissue and outputs high-frequency energy, so that the living tissue can be altered. A counter electrode plate (not shown) paired with the electrode 34 is attached to the body surface. The distal outer layer 31B insulates the distal inner layer 31A. The puncture portion 31 has a side hole 35 that opens on the outer peripheral surface. The puncture portion 31 does not have to have a two-layer structure. The puncture portion 31 may not be provided with the insulating distal outer layer 31B if the entire body is the electrode 34. Further, if a conducting wire having conductivity can be arranged inside the puncture portion 31, the proximal portion of the puncture portion 31 does not have to have conductivity. The outer diameter of the puncture portion 31 is smaller than the outer diameter of the proximal shaft 33 and the flexible portion 32. The inner diameter of the puncture portion 31 substantially coincides with the inner diameter of the needle portion 30 and the flexible portion 32. The inner diameter of the puncture portion 31 may be different from the inner diameter of the needle portion 30 and the flexible portion 32. The bending rigidity of the puncture portion 31 is larger than the bending rigidity of the sheath assembly 20. Further, the bending rigidity of the puncture portion 31 is larger than the bending rigidity of the dilator 40 and larger than the bending rigidity of the outer sheath 50.

The flexible portion 32 is a tubular body located between the proximal shaft 33 and the puncture portion 31. The length of the flexible portion 32 is preferably longer than the length of the puncture portion 31 and longer than the length of the proximal shaft 33. The bending rigidity of the flexible portion 32 is lower than the bending rigidity of the proximal shaft 33 and the puncture portion 31. Further, the bending rigidity of the flexible portion 32 is lower than the bending rigidity of the sheath assembly 20 in which the dilator 40 and the outer sheath 50 are combined. In particular, the bending rigidity of the flexible portion 32 is lower than the bending rigidity in the range in which the flexible portion 32 of the sheath assembly 20 can be inserted.

Further, the bending rigidity of the flexible portion 32 is lower than the bending rigidity of the dilator 40. In particular, the bending rigidity of the flexible portion 32 is lower than the bending rigidity in the range in which the flexible portion 32 of the dilator 40 can be inserted.

Further, the bending rigidity of the flexible portion 32 is lower than the bending rigidity of the outer sheath 50. In particular, the bending rigidity of the flexible portion 32 is lower than the bending rigidity in the range in which the flexible portion 32 of the outer sheath 50 can be inserted.

The flexible portion 32 has a flexible and flexible insulating flexible support portion 32A and a support portion 32B embedded in the flexible support portion 32A. The support portion 32B is formed in a net shape by braiding while crossing a plurality of conductive wire rods. The support portion 32B has a plurality of gaps penetrating in the radial direction, and the flexible support portion 32A is inserted into the gaps. High flexibility can be obtained by having the support portion 32B having a gap. Further, the support portion 32B suppresses the kink of the flexible portion 32. The distal end of the support 32B is connected to the distal inner layer 31A. The proximal end of the support 32B is connected to the proximal inner layer 33A. Therefore, the conductive support portion 32B can transmit the current supplied from the proximal inner layer 33A to the electrode 34 of the distal inner layer 31A. The flexible support portion 32A insulates the support portion 32B. The flexible support portion 32A closes the gap of the support portion 32B while maintaining the flexibility of the flexible portion 32. Therefore, the flexible support portion 32A maintains the lumen of the needle portion 30 in a liquid-tight manner. Thereby, the drug, contrast agent, physiological saline, blood and the like can be delivered by utilizing the lumen of the needle portion 30. The flexible support portion 32A may be composed of one layer, but may be composed of two layers or two or more layers so as to sandwich the support portion 32B. The outer diameter of the flexible portion 32 is substantially the same as that of the proximal shaft 33, but may be different. The inner diameter of the flexible portion 32 is substantially the same as that of the proximal shaft 33, but may be different.

The puncture portion 31 does not have to be due to a high frequency current, and may be, for example, one that outputs energy such as an electromagnetic wave, a laser, or cooling to denature a living tissue to form a hole. Further, the puncture portion 31 may be a structurally sharp mechanical puncture needle. Further, the needle portion may be solid.

The constituent materials of the proximal inner layer 33A, the distal inner layer 31A and the support portion 32B are not particularly limited as long as they have conductivity, and are, for example, stainless steel, Au (gold), Pt (platinum), tungsten, titanium and the like. The proximal inner layer 33A, the distal inner layer 31A and the support portion 32B do not have to have conductivity. In this case, the insulating proximal outer layer 33B and the distal outer layer 31B may not be provided.

The constituent materials of the proximal outer layer 33B and the distal outer layer 31B are not particularly limited as long as they have insulating properties, and are, for example, polyolefins such as polyethylene and polypropylene, polyamides, polyesters such as polyethylene terephthalate, and PTFE (polytetrafluoroethylene). Fluorine-based polymers such as ETFE (ethylene / tetrafluoroethylene copolymer), PEEK (polyether ether ketone), polyimide and the like can be preferably used. The constituent materials of the proximal outer layer 33B and the distal outer layer 31B are particularly preferably low friction materials that easily slide with the inner peripheral surface of the dilator 40, for example, PTFE (polytetrafluoroethylene), ETFE (ethylene, 4). Fluorine-based polymers such as (fluoroethylene copolymer)) are preferable.

The constituent material of the flexible support portion 32A is preferably flexible and flexible, for example, polyolefins such as polyethylene and polypropylene, polyesters such as polybutylene terephthalate, polyamide and polyethylene terephthalate, PTFE (polytetrafluoroethylene) and ETFE. Fluorine-based polymers such as (ethylene / tetrafluoroethylene copolymer), PEEK (polyether ether ketone), polyimide and the like can be preferably used.

The length of the needle portion 30 is appropriately set, but is, for example, 500 to 1100 mm. The length of the puncture portion 31 is appropriately set, and is, for example, 5 to 30 mm, more preferably 5 to 25 mm, still more preferably 10 to 20 mm. The length of the flexible portion 32 is appropriately set, and is, for example, 20 to 90 mm, more preferably 30 to 80 mm, still more preferably 40 to 70 mm. The length of the proximal shaft 33 is set as appropriate, but is, for example, 350 to 1800 mm, more preferably 380 to 1200 mm, and even more preferably 400 to 1000 mm. The outer diameter of the puncture portion 31 is appropriately set, and is, for example, 0.5 to 1.0 mm. The inner diameter of the needle portion 30 is appropriately set, but is, for example, 0.3 to 0.8 mm.

The operation unit 60 is a portion for gripping and operating the needle unit 30. The proximal portion of the needle portion 30 is fixed to the operation portion 60. The operation unit 60 includes a proximal side opening 61 and a connector 62. The proximal opening 61 communicates with the lumen of the needle 30. By connecting a syringe or the like to the proximal side opening 61, the lumen of the needle portion 30 can be primed, or a contrast medium, a drug, or the like can be injected into the needle portion 30. In addition, blood pressure can be measured by guiding blood in the living body to the outside through the proximal opening 61. By measuring the blood pressure, it can be confirmed accurately that the puncture portion 31 has reached the target position. The connector 62 can be connected to an external power supply device that supplies a high frequency current to the electrode 34.

The constituent material of the operation unit 60 is not particularly limited, but for example, a hard resin such as polycarbonate, polyethylene, polypropylene, ABS resin (general term for acrylonitrile, butadiene, and styrene copolymer synthetic resin), a metal such as stainless steel, and the like are preferable. Can be used.

The dilator 40 is used to widen the hole in the fossa ovalis O formed by the needle portion 30. The dilator 40 has a tapered portion 42 at the distal end, which is tapered toward the distal side. The lumen of the dilator 40 is open at the most contracted end of the tapered portion 42. The inclination angle α1 with respect to the central axis of the tapered portion 42 is appropriately set, and is, for example, 1 to 20 degrees, more preferably 3 to 15 degrees, still more preferably 4 to 10 degrees. A connecting portion 41 that can be connected to a Y connector or the like is provided on the outer peripheral surface of the proximal portion of the dilator 40. The connection portion 41 is a male connector.

The dilator 40 has a dilator distal portion 43 having a small inner diameter on the distal side and a dilator proximal portion 44 having a larger inner diameter than the dilator distal portion 43 on the proximal side. An inner diameter reduced portion 45 whose inner diameter is reduced toward the distal side is provided between the dilator distal portion 43 and the dilator proximal portion 44. The inner peripheral surface of the distal portion 43 of the dilator is slidably close to the outer peripheral surface of the puncture portion 31 of the needle portion 30. The inner diameter of the proximal dilator 44 is larger than the outer diameter of the needle 30. Therefore, the needle portion 30 can be easily inserted into the proximal portion 44 of the dilator. The inner diameter of the distal dilator 43 is greater than or equal to the outer diameter of the puncture portion 31 and smaller than the outer diameter of the flexible portion 32. Therefore, the distal dilator 43 can accommodate the puncture portion 31, but cannot accommodate the flexible portion 32. When the needle portion 30 is inserted into the dilator 40, the puncture portion 31 passes through the dilator distal portion 43, is guided to the inner diameter reduced portion 45, and enters the dilator distal portion 43. Since the puncture portion 31 is in close contact with the inner peripheral surface of the dilator distal portion 43, the puncture portion 31 is accurately positioned with respect to the dilator 40. When the needle portion 30 is further pushed into the dilator 40, the electrode 34 protrudes from the dilator 40, and the step between the flexible portion 32 and the puncture portion 31 abuts on the inner diameter reduced portion 45. As a result, it is possible to prevent the electrode 34 from protruding too much from the dilator 40, and the safety is high. The step that abuts on the inner diameter reduced portion 45 does not have to be the step between the flexible portion 32 and the puncture portion 31. The step that abuts on the inner diameter reduced portion 45 may be a step between the flexible portion 32 and the proximal shaft 33, or a step provided at another portion.

The dilator 40 naturally has a dilator bending portion 46 bent at a predetermined angle at the distal portion. The angle β1 of the dilator bending portion 46 with respect to the proximal portion of the dilator 40 is not particularly limited, but is, for example, 10 to 120 degrees, more preferably 20 to 100 degrees, still more preferably 30 to 90 degrees. The dilator bending portion 46 serves to direct the puncture portion 31 of the needle portion 30 inserted into the right atrium R and the tapered portion 42 of the dilator 40 toward the oviduct O. The length of the dilator bent portion 46 is preferably about the same as the length of the flexible portion 32.

The length of the dilator 40 is appropriately set, and is, for example, 400 to 1500 mm. The outer diameter of the dilator 40 is appropriately set, but is, for example, 2 to 6 mm. The inner diameter of the distal portion 43 of the dilator is appropriately set, but is, for example, 0.5 to 1.5 mm. The inner diameter of the proximal portion 44 of the dilator is appropriately set, but is, for example, 1.0 to 2.0 mm. The length of the distal dilator 43 is appropriately set, but is, for example, 1 to 15 mm, more preferably 2 to 12 mm, still more preferably 3 to 10 mm.

The constituent material of the dilator 40 is preferably flexible, and for example, polyethylene, a polyolefin such as polypropylene, a polyamide, a polyester such as polyethylene terephthalate, PTFE (polytetrafluoroethylene), and ETFE (both ethylene and tetrafluoroethylene). Fluorine-based polymers such as polymer), PEEK (polyether ether ketone), polyimide, shape memory alloys, stainless steel, tantalum, titanium, platinum, gold, tungsten and other metals can be preferably used. Further, the dilator 40 may include an X-ray contrast-enhancing material or an ultrasonic contrast-enhancing material.

The outer sheath 50 provides an access route for the ablation catheter. The outer sheath 50 has a sheath body 51, a hub 54 connected to a proximal portion of the sheath body 51, a sheath port portion 56 communicating with the hub 54, and a valve body 55 inside the hub 54. ..

The sheath body 51 is a long tube that accommodates the dilator 40 so as to be movable in the axial direction. The sheath body 51 has an inner peripheral surface that smoothly slides with the dilator 40. The sheath body 51 naturally has a sheath bent portion 52 bent at a predetermined angle at the distal portion. The angle β2 of the sheath bending portion 52 with respect to the proximal portion of the sheath main body 51 is not particularly limited, but is, for example, 10 to 180 degrees, more preferably 30 to 150 degrees, still more preferably 45 to 135 degrees. The sheath bending portion 52 serves to direct the puncture portion 31 of the needle portion 30 inserted into the right atrium R and the distal portion of the sheath body 51 toward the fossa ovalis. The length of the sheath bent portion 52 is preferably about the same as the length of the flexible portion 32.

The sheath body 51 has a sheath tapered portion 53 at the distal end, which is tapered toward the distal side. The lumen of the sheath body 51 is open at the most contracted end of the sheath taper 53. The inclination angle α2 with respect to the central axis of the sheath taper portion 53 is appropriately set, but is, for example, 1 to 15 degrees, more preferably 2 to 10 degrees, still more preferably 3 to 7 degrees. In the sheath assembly 20 in which the dilator 40 is inserted into the outer sheath 50, the sheath tapered portion 53 is located on the proximal side of the tapered portion 42 of the dilator 40 and can be positioned so as to be continuous with the tapered portion 42. It is preferable that the inner peripheral surface of the sheath body 51 has a clearance with the outer peripheral surface of the dilator 40 so that the outer peripheral surface of the dilator 40 is slidably contacted.

The dilator 40 can penetrate the sheath body 51 over its entire length. Therefore, the axial length of the sheath body 51 is shorter than that of the dilator 40.

The length of the sheath body 51 is appropriately set, but is, for example, 400 to 1000 mm. The outer diameter of the sheath body 51 is appropriately set, but is, for example, 2.5 to 7.0 mm. The inner diameter of the sheath body 51 is appropriately set, but is, for example, 2 to 6 mm. The clearance at the radius between the inner peripheral surface of the sheath body 51 and the outer peripheral surface of the dilator 40 is appropriately set, and is, for example, 0.01 to 0.5 mm.

The constituent material of the sheath body 51 is preferably a flexible material, for example, a polyolefin such as polyethylene and polypropylene, a polyamide, a polyester such as polyethylene terephthalate, PTFE (polytetrafluoroethylene), and ETFE (ethylene, 4). Fluorine-based polymers such as (fluoroethylene copolymer), PEEK (polyether ether ketone), polyimide and the like can be preferably used. Further, the constituent material of the sheath body 51 may include an X-ray contrast-enhancing material, an ultrasonic contrast-enhancing material, a metal wire, and a coil.

The hub 54 is provided proximal to the sheath body 51 and communicates with the lumen of the sheath body 51. A dilator 40 penetrates the hub 54. The sheath port portion 56 is connected to the hub 54 and communicates with the lumen of the sheath body 51 via the lumen of the hub 54. The sheath port portion 56 has a three-way stopcock 57 at the end thereof. By connecting a syringe or the like to the three-way stopcock 57, the lumen of the sheath body 51 can be primed, or a contrast medium, a drug, or the like can be injected into the sheath body 51.

The valve body 55 is a member for sealing the lumens of the hub 54 and the sheath body 51. The valve body 55 is flexibly deformable and is arranged on the inner peripheral surface of the hub 54. The valve body 55 slidably contacts the outer peripheral surface of the dilator 40. Further, the valve body 55 can press the dilator 40 by an elastic force with the dilator 40 inserted to fix the dilator 40 and the outer sheath 50. Even if it is fixed by the valve body 55, it can be relatively moved in the axial direction by gripping the dilator 40 and the outer sheath 50 and applying a force. Further, by pulling out the dilator 40 from the hub 54, the hole into which the dilator 40 of the valve body 55 is inserted is closed, and the lumen of the hub 54 is sealed from the proximal side. The valve body 55 is, for example, a member having a cut in the center of a disk-shaped elastic body. The elastic body is, for example, natural rubber, silicone rubber, various elastomers and the like. The valve body 55 suppresses blood leakage through the outer sheath 50 and suppresses air from entering the body while allowing the dilator 40 to be inserted and removed.

In a state where the dilator 40 and the outer sheath 50 are combined, it is preferable that the positions and bending directions of the dilator bending portion 46 and the sheath bending portion 52 are the same or substantially the same. As a result, the puncture portion 31 can be projected in a desired direction.

Next, a method of making a hole in the fossa ovalis O using the medical device 1 according to the embodiment to provide an access route for the ablation catheter will be described.

First, a needle is punctured into the femoral vein and a short guide wire is inserted into the needle. The needle is then removed and a catheter introducer is inserted into the blood vessel along the short guide wire. Next, the sheath assembly 20 in which the dilator 40 is inserted inside the outer sheath 50 is prepared. Subsequently, the short guide wire is removed and the guide wire 70 is inserted into the catheter introducer. Next, the catheter introducer is removed while leaving the guide wire 70 in the blood vessel, and the proximal end of the guide wire 70 is inserted inward from the distal end of the dilator 40. Next, the sheath assembly 20 is inserted into the catheter introducer and inserted into the blood vessel. Subsequently, as shown in FIG. 5A, the distal portion of the sheath assembly 20 is gradually pushed to the right atrium R while leading the guide wire 70. Next, the sheath assembly 20 is once inserted from the right atrium R into the superior vena cava along the guide wire 70. Subsequently, once the tip of the guide wire 70 is housed in the sheath assembly 20, the sheath assembly 20 is retracted and pulled into the right atrium R, as shown in FIGS. 4 and 5 (B). The distal end of the sheath assembly 20 is guided to naturally abut the fossa ovalis O.

Next, as shown in FIG. 5C, the puncture device 10 is inserted into the lumen of the dilator 40 from the proximal side of the dilator 40. The puncture portion 31 of the puncture device 10 reaches the distal portion 43 of the dilator through the proximal portion 44 of the dilator and the inner diameter reduced portion 45. Then, the electrode 34 at the most distal portion of the puncture device 10 is arranged at a position proximal to about 5 mm from the distal opening of the dilator 40. That is, the electrode 34 is arranged at a position immediately before protruding from the dilator 40. At this time, the flexible portion 32 is located inside the sheath bending portion 52 and the dilator bending portion 46. When the needle portion 30 is inserted into the dilator 40, the flexible portion 32 of the needle portion 30 has low bending rigidity, so that it can be easily deformed following the shape of the dilator 40. Therefore, the sliding resistance when the needle portion 30 is inserted into the dilator 40 is reduced, and the operability is improved. In particular, when the needle portion 30 is inserted into the dilator bending portion 46 and the sheath bending portion 52, the flexible portion 32 is easily bent to reduce the sliding resistance and improve the operability. Further, since the flexible portion 32 is easily bent, the shapes of the dilator 40 and the outer sheath 50 are less likely to be interfered with by the flexible portion 32. Therefore, the change in the positions of the dilator 40 and the outer sheath 50 is small, and the desired position can be maintained. When inserting the puncture device 10 into the dilator 40, the dilator 40 may be once pulled out from the outer sheath 50. In this case, the puncture device 10 is inserted into the lumen of the extracted dilator 40, and the dilator 40 accommodating the puncture device 10 is inserted into the outer sheath 50 again.

Subsequently, the dilator 40 is pushed distally while observing the inside of the left atrium L and the right atrium R with an intracardiac echocardiographic catheter (ICE). As a result, the ovary fossa O is pushed toward the left atrium L side by the dilator 40 and is in a protruding state. At this time, since the distal portions of the outer sheath 50 and the dilator 40 are bent, the distal end portion of the dilator 40 can be easily directed to the fossa ovalis O. The oviduct O does not have to be in a state of protruding toward the left atrium L side.

Next, the external power supply device is operated to apply a high frequency current to the electrode 34. Subsequently, as shown in FIG. 5D, the operation unit 60 located outside the body is pushed in, and the puncture unit 31 is moved to the distal side. As a result, the electrode 34 protrudes distally from the dilator 40. The electrode 34 cauterizes the living tissue in contact and forms a hole in the fossa ovalis O. When the needle portion 30 is further pushed into the dilator 40, the step between the flexible portion 32 and the puncture portion 31 abuts on the inner diameter reduced portion 45. As a result, it is possible to prevent the electrode 34 from protruding too much from the dilator 40. Therefore, it is possible to suppress erroneous puncture of an unintended site, and the safety is high.

The flexible portion 32 of the needle portion 30 has a lower bending rigidity than the sheath assembly 20. Therefore, when the electrode 34 protrudes from the dilator 40, the flexible portion 32 can be easily deformed by following the shape of the sheath assembly 20. That is, the flexible portion 32 can be positioned inside the dilator bending portion 46 and the sheath bending portion 52 in a state where the puncture portion 31 protrudes distally from the dilator 40. Therefore, when the needle portion 30 moves inside the dilator bending portion 46 and the sheath bending portion 52, the flexible portion 32 is easily bent to reduce the sliding resistance and improve the operability. Further, since the flexible portion 32 is easily bent, the shape of the sheath assembly 20 is less likely to be interfered with by the flexible portion 32. In particular, the bending angles of the dilator bent portion 46 and the sheath bent portion 52 are unlikely to change. Therefore, when puncturing, the change in the position of the sheath assembly 20 is small. Therefore, the position where the tapered portion 42 abuts on the fossa ovalis O is less likely to shift during puncture. Therefore, the electrode 34 can puncture an accurate position.

When the puncture portion 31 penetrates the ovary fossa O, a part of the distal end of the dilator 40 that has pressed the ovary fossa O toward the left atrium L side enters the hole made in the ovary fossa O. .. It should be noted that a part of the dilator 40 does not have to enter the hole of the fossa ovalis O. When the electrode 34 penetrates the fossa ovalis O, the puncture portion 31 reaches the left atrium L by measuring the blood pressure from the proximal side opening 61 through the side hole 35 located at the electrode 34. Can be confirmed. It is also possible to confirm that the puncture portion 31 has reached the left atrium L by discharging the contrast medium from the side hole 35 of the needle portion 30 to the left atrium L.

Next, the medical device 1 is moved to the distal side. As a result, as shown in FIG. 6A, the tapered portion 42 of the dilator 40 and the sheath tapered portion 53 of the outer sheath 50 pass through the oviduct O while expanding the hole of the oviduct O, and the left atrium L. To reach. At this time, since the tapered portion 42 and the sheath tapered portion 53 are reduced in diameter toward the distal side, the hole of the fossa ovalis O can be smoothly widened. Further, since the puncture portion 31 is maintained in a protruding state in which the fossa ovalis O is punctured, the dilator 40 and the outer sheath 50 can be easily pushed into the hole of the fossa ovalis O along the puncture portion 31. can. Further, when the fossa ovalis O is punctured by the puncture portion 31, a part of the tapered portion 42 of the dilator 40 has entered the hole of the fossa ovalis O, so that the dilator 40 and the outer sheath 50 are inserted into the fossa ovalis. It is easy to push it into the hole of O.

Next, as shown in FIG. 6B, the puncture device 10 is removed from the body, leaving the dilator 40 and the outer sheath 50. The hole in the fossa ovalis O widened by the dilator 40 is maintained by the outer sheath 50. Next, the guide wire 70 is inserted into the lumen of the dilator 40, and the guide wire 70 is inserted into the pulmonary artery while leading the guide wire 70. Next, when the guide wire 70 and the dilator 40 are removed from the outer sheath 50, the valve body 55 is closed, and blood leakage and air contamination into the blood vessel can be suppressed. After that, as shown in FIG. 6C, the ablation catheter 71 is inserted from the proximal side of the outer sheath 50 via the valve body 55. Thereby, the ablation catheter 71 can be inserted into the left atrium L by utilizing the outer sheath 50 penetrating the oviduct O. After ablation is performed in the left atrium L by the ablation catheter 71, when the ablation catheter 71 and the outer sheath 50 are removed from the body, the hole of the fossa ovalis O contracts. This completes the procedure.

As described above, the puncture device 10 of the present embodiment is inserted into the tubular sheath assembly 20 (long body), and the fossa ovalis O (living tissue) in the living body is cauterized through the sheath assembly 20. A puncture device 10 for forming a hole, which is a conductive metal puncture portion 31 located on the distal side for puncturing the fossa ovalis O and a long elongated portion located on the proximal side. It has a proximal shaft 33 and a flexible portion 32 located between the puncture portion 31 and the proximal shaft 33, the bending rigidity of which is lower than the bending rigidity of the puncture portion 31 and the proximal shaft 33. The long body into which the puncture device 10 is inserted may be the sheath assembly 20 or the dilator 40.

In the puncture device 10 configured as described above, since the flexible portion 32 is more flexible than the puncture portion 31 and the proximal shaft 33, even if the flexible portion 32 is inserted into the sheath assembly 20, the flexible portion 32 has the shape of the sheath assembly 20. It is hard to interfere with. Therefore, when the puncture portion 31 is projected from the sheath assembly 20 to the distal side, the shape of the sheath assembly 20 is maintained, and the target position can be punctured with high position accuracy. Further, since the flexible portion 32 does not easily interfere with the shape of the sheath assembly 20, the sliding resistance when the puncture device 10 is moved inside the sheath assembly 20 is reduced. Therefore, the puncture device 10 can be easily inserted into the sheath assembly 20, and the operability is improved.

Further, the flexible portion 32 has a metal support portion 32B having conductivity. Therefore, the flexible portion 32 can supply high frequency energy to the puncture portion 31 by using the conductive support portion 32.

Further, the flexible portion 32 has a conductive metal support portion 32B provided with a gap penetrating in the radial direction. Therefore, the flexible portion 32 can maintain the flexibility while suppressing the generation of kink by the metal support portion 32.

Further, the proximal shaft 33 is made of a conductive metal, and the proximal shaft 33, the support portion 32B and the puncture portion 31 are electrically connected to each other. Thereby, the high frequency energy supplied from the external power supply device can be transmitted to the puncture portion 31 via the proximal shaft 33 and the support portion 32B. Further, since the puncture portion 31 and the proximal shaft 33 are made of metal, it is easy to set the bending rigidity higher than that of the flexible portion 32.

Further, the flexible portion 32 has a flexible support portion 32A made of resin that closes the gap between the support portions 32B. As a result, the lumen of the flexible portion 32 can be made liquid-tight while maintaining the flexible portion 32 flexibly. The flexible support portion 32A may not be provided.

Further, the medical device 1 according to the present embodiment is a medical device 1 for cauterizing the fossa ovalis O (living tissue) in the living body to form a hole, and the fossa ovalis O is cauterized and punctured. It has a piercing device 10 for the purpose, a tubular dilator 40 into which the piercing device 10 is inserted, and a tubular outer sheath 50 into which the dilator 40 is inserted, and the piercing device 10 is located distally to the egg. The puncture portion 31 for puncturing the fossa ovalis, the long proximal shaft 33 located on the proximal side, and the puncture portion 31 and the proximal shaft located between the puncture portion 31 and the proximal shaft 33. It has a flexible portion 32 that is lower than the bending rigidity of 33 and lower than the bending rigidity of the sheath assembly 20 in which the dilator 40 is inserted into the outer sheath 50.

In the medical device 1 configured as described above, since the flexible portion 32 is more flexible than the puncture portion 31 and the proximal shaft 33 and more flexible than the sheath assembly 20, the puncture device 10 is attached to the sheath assembly 20. Even if it is inserted, the flexible portion 32 does not easily interfere with the shape of the sheath assembly 20. Therefore, when the puncture portion 31 is projected from the sheath assembly 20 to the distal side, the shape of the sheath assembly 20 is maintained, and the target position can be punctured with high position accuracy. Further, since the flexible portion 32 does not easily interfere with the shape of the sheath assembly 20, the sliding resistance when the puncture device 10 is moved inside the sheath assembly 20 is reduced. Therefore, the puncture device 10 can be easily inserted into the sheath assembly 20, and the operability is improved.

Further, the bending rigidity of the flexible portion 32 is lower than the bending rigidity of the dilator 40 and lower than the bending rigidity of the outer sheath 50. Therefore, when the puncture portion 31 is projected from the dilator 40 or the outer sheath 50 to the distal side, the shape of the dilator 40 or the outer sheath 50 is maintained, and the target position can be punctured with high position accuracy. Further, even if the puncture device 10 is inserted into the dilator 40 or the outer sheath 50, the flexible portion 32 does not easily interfere with the shape of the dilator 40 or the outer sheath 50. Therefore, the puncture device 10 can be easily inserted into the dilator 40 or the outer sheath 50, and the operability is further improved.

Further, at least one of the distal portion of the dilator 40 and the outer sheath 50 is bent with respect to the central axis, and in a state where the puncture portion 31 protrudes distally from the dilator 40, the bent portion (dilator bending portion). The flexible portion 32 can be positioned inside the 46 and the sheath bent portion 52). As a result, the dilator bending portion 46 and the sheath bending portion 52 make it easy to direct the puncture portion 31 to the target position for puncture. Further, since the puncture device 10 has the flexible portion 32, the curved shape of the dilator 40 and the outer sheath 50 can be appropriately maintained when the puncture portion 31 is projected distally from the sheath assembly 20. Therefore, the dilator bending portion 46 and the sheath bending portion 52 can puncture the target position with high position accuracy while directing the puncture portion 31 in an appropriate direction.

The present invention also includes a treatment method (treatment method) for cauterizing the fossa ovalis O (living tissue) in a living body using the above-mentioned medical device 1 to form a hole. The treatment method includes a step of inserting the sheath assembly 20 and the puncture device 10 into the living body, and the flexible portion 32 is moved inside the sheath assembly 20 so that the puncture portion 31 is projected from the sheath assembly 20 to form an egg circle. It has a step of puncturing the fossa O.

In the treatment method configured as described above, the bending rigidity of the flexible portion 32 of the puncture device 10 used is lower than the bending rigidity of the puncturing portion 31 and the proximal shaft 33, and is lower than the bending rigidity of the sheath assembly 20. Therefore, even if the puncture device 10 is inserted into the sheath assembly 20, the flexible portion 32 does not easily interfere with the shape of the sheath assembly 20. Therefore, when the puncture portion 31 is projected from the sheath assembly 20, the shape of the sheath assembly 20 is maintained, and the target position can be punctured with high position accuracy. Further, since the flexible portion 32 does not easily interfere with the shape of the sheath assembly 20, the sliding resistance when the puncture device 10 is moved inside the sheath assembly 20 is reduced. Therefore, the puncture device 10 can be easily inserted into the sheath assembly 20, and the operability is improved.

The present invention is not limited to the above-described embodiment, and various modifications can be made by those skilled in the art within the technical idea of the present invention. For example, the medical device described above may be used to puncture a living tissue in the living body other than the fossa ovalis.

Further, as in the first modification shown in FIG. 7, the proximal shaft 81 of the puncture device 80 may have a shaft bending portion 82 that bends with respect to the central axis on the proximal side at the distal portion. .. The same reference numerals are given to the parts having the same functions as those of the above-described embodiment, and the description thereof will be omitted. The proximal shaft 81 has higher flexural rigidity than the sheath assembly 90. The angle β3 of the shaft bending portion 82 with respect to the proximal portion is not particularly limited, but is, for example, 10 to 120 degrees, more preferably 20 to 100 degrees, still more preferably 30 to 90 degrees. The shaft bending portion 82 may be deformable by the operator prior to being inserted into the dilator 40. This makes it possible to adjust the angle β of the shaft bent portion 82 to a desired angle. In this case, the constituent material of the proximal shaft 81 preferably contains a material capable of plastic deformation. Further, the angles of the flexible portion 32 and the puncture portion 31 with respect to the central axis on the proximal side may be adjustable to a desired angle. The proximal shaft 81 has higher bending rigidity than the sheath assembly 90 in which the dilator 91 and the outer sheath 92 are combined. The dilator 91 has no dilator bending portion and is linear. The dilator may have a dilator bending portion 46 (see FIG. 1). The outer sheath 92 is linear without a sheath bent portion. The outer sheath may have a sheath bent portion 52 (see FIG. 1). Since the proximal shaft 81 has the shaft bent portion 82, it becomes easy to direct the puncture portion 31 to the target position for puncture. Further, even if the shaft bending portion 82 is present on the proximal shaft 81, the flexible portion 32 is provided on the distal side of the proximal shaft 81. Therefore, even if the puncture device 80 is inserted into the sheath assembly 90, the interference of the shaft bending portion 82 with the sheath assembly 90 can be reduced. As a result, the sliding resistance between the puncture device 80 and the dilator 91 can be reduced, and the operability can be improved. Further, when the puncture portion 31 is projected to the distal side from the sheath assembly 90, the puncture portion 31 can be oriented in an appropriate direction by the shaft bending portion 82, and the target position can be punctured with high position accuracy. Further, the shaft bending portion 82 has a higher bending rigidity than the sheath assembly 90. Therefore, even if the sheath assembly 90 does not have a bent portion, the puncture portion 31 can be directed to a target position to be punctured by the shape of the puncture device 80 without depending on the shape of the sheath assembly 90. ..

Further, as in the second modification shown in FIG. 8, the flexible portion 101 of the puncture device 100 may have a flexible bending portion 102 that bends with respect to the central axis on the proximal side. This makes it even easier to direct the puncture portion 31 to the desired position for puncture.

Further, although the proximal shaft 33 in the above-described embodiment is independently composed of one member, it may be composed of a part of one member. If the proximal shaft is part of one member, the member on which the proximal shaft is provided may also have a flexible portion or a puncture portion. That is, the proximal shaft and the flexible portion may be composed of one member. Further, the proximal shaft, the flexible portion and the puncture portion may be composed of one member. When the proximal shaft is a part of one member, the portion located proximal to the portion of the member that is the flexible portion is the proximal shaft.

As in the third modification shown in FIG. 9A, the puncture portion 112, the flexible portion 113, and the proximal shaft 114 of the puncture device 110 may be formed by one tubular member 111 having conductivity. The portion of the tubular member 111 corresponding to the flexible portion 113 has a lower bending rigidity than the puncture portion 112 and the proximal shaft 114 due to the formation of the spiral slit 115. The slit 115 penetrates from the inner peripheral surface to the outer peripheral surface of the tubular member 111 and has a gap (width). The slit 115 can be easily formed by laser processing or the like. The proximal shaft 114, the flexible portion 113 and the proximal portion of the puncture portion 112 are covered with a covering portion 116 made of an insulating material. The tubular member 111 located in the flexible portion 113 is a support portion having a gap (slit 115), and the covering portion 116 located in the flexible portion 113 is a flexible support portion that closes the gap in the support portion. As the constituent material of the tubular member 111, a material applicable to the above-mentioned distal inner layer 31A and proximal inner layer 33A can be applied. As the constituent material of the covering portion 116, a material applicable to the above-mentioned distal outer layer 31B and proximal outer layer 33B can be applied. Since the flexible portion 113 of the puncture device 110 is more flexible than the puncture portion 112 and the proximal shaft 114, it is easy to bend at the flexible portion 113 as shown in FIG. 9B. Further, since the proximal shaft 114, the flexible portion 113, and the puncture portion 112 are formed of one tubular member 111 having conductivity, the current can be reliably transmitted to the electrode 112A.

Further, as in the fourth modification shown in FIG. 10A, the puncture portion 122, the flexible portion 123, and the proximal shaft 124 of the puncture device are attached to one tubular member 121 having conductivity and the tubular member 121. It may be formed by the flexible support portion 126 to be fitted. The portion of the tubular member 121 corresponding to the flexible portion 123 has a notch portion 125 that is partially cut out along the axial direction in the circumferential direction. The tubular member 121 located in the flexible portion 123 is a support portion having a gap (notch portion 125), and the flexible support portion 126 closes the gap in the support portion. The cutout portion 125 penetrates from the inner peripheral surface of the tubular member 121 to the outer peripheral surface. The cutout portion 125 can be easily formed by laser processing or the like. The flexible support portion 126 is joined to the tubular member 121 so as to fill the notch portion 125. The flexible support portion 126 is made of a material that is more flexible than the tubular member 121. The proximal shaft 124, the flexible portion 123 and the proximal portion of the puncture portion 122 are covered with a covering portion 127 made of an insulating material. As the constituent material of the tubular member 121, a material applicable to the above-mentioned distal inner layer 31A and proximal inner layer 33A can be applied. As the constituent materials of the flexible support portion 126 and the covering portion 127, materials applicable to the above-mentioned distal outer layer 31B and proximal outer layer 33B can be applied. The flexible portion 123 has a first side surface 128 and a second side surface 129 with the central axis interposed therebetween. The flexible support portion 126 is arranged on the second side surface 129. Therefore, the second side surface 129 side of the flexible portion 123 can be contracted and expanded with a smaller force along the axial direction than the first side surface 128 side. As a result, as shown in FIG. 10B, the flexible portion 123 can be easily curved by contracting the second side surface 129 side of the flexible portion 123. Further, by expanding the second side surface 129 side of the flexible portion 123, the flexible portion 123 can easily return from the curved state to a shape close to a straight line. Further, since the proximal shaft 124, the flexible portion 123, and the puncture portion 122 are formed of one tubular member 121 having conductivity, the current can be reliably transmitted to the electrode 122A.

Further, the puncture device 130 of the fifth modification shown in FIG. 11A has one tubular member 131 having conductivity to form the puncture portion 132, the flexible portion 133, and the proximal shaft 134. The portion of the tubular member 131 corresponding to the flexible portion 133 is formed with a plurality of notched portions 135 in which a part of the tubular member 131 is notched in the circumferential direction. The plurality of notch portions 135 are arranged side by side in the axial direction. The cutout portion 135 penetrates from the inner peripheral surface to the outer peripheral surface of the tubular member 131. The cutout portion 135 can be easily formed by laser processing or the like. The flexible portion 133 has a lower bending rigidity than the puncture portion 132 and the proximal shaft 134 due to the formation of the plurality of cutout portions 135. The proximal shaft 134, the flexible portion 133 and the proximal portion of the puncture portion 132 are covered with a covering portion 137 made of an insulating material. The tubular member 131 located in the flexible portion 133 is a support portion having a gap (notch portion 135), and the covering portion 137 located in the flexible portion 133 is a flexible support portion that closes the gap in the support portion. As the constituent material of the tubular member 131, a material applicable to the above-mentioned distal inner layer 31A and proximal inner layer 33A can be applied. As the constituent material of the covering portion 137, a material applicable to the above-mentioned distal outer layer 31B and proximal outer layer 33B can be applied. The flexible portion 133 has a first side surface 138 and a second side surface 139 with the central axis interposed therebetween. The plurality of notches 135 are arranged on the second side surface 139. Therefore, the second side surface 139 side of the flexible portion 133 can be contracted and expanded with a smaller force along the axial direction than the first side surface 138 side. As a result, as shown in FIG. 11B, the flexible portion 133 can be easily curved by contracting the second side surface 139 side of the flexible portion 133. Further, by expanding the second side surface 139 side of the curved portion, the flexible portion 133 can easily return from the curved state to a shape close to a straight line. Further, since the proximal shaft 134, the flexible portion 133, and the puncture portion 132 are formed of one tubular member 131 having conductivity, the current can be reliably transmitted to the electrode 132A.

Further, as in the fifth modification shown in FIG. 12A, the puncture device 140 may be provided with a tow wire 141 for bending the flexible portion 32 by a hand operation. The tow wire 141 is slidably arranged in the lumen of the needle portion 142 and extends along the needle portion 142. The distal end of the tow wire 141 is fixed to a fixation portion 143 located on the inner peripheral surface of the distal portion of the flexible portion 32. The distal end of the tow wire 141 may be fixed to the puncture portion 31 distal to the flexible portion 32. The proximal end of the tow wire 141 is fixed to a slide portion 145 slidably provided on the operation portion 144. The proximal portion of the tow wire 141 is derived from an opening 146 formed on the side surface of the needle portion 142 located inside the operating portion 144. The tow wire 141 introduced from the opening 146 passes through the seal member 147 and is fixed to the slide portion 145. When the flexible portion 32 is linear, when the slide portion 145 at hand is moved to the proximal side, the tow wire 141 moves to the proximal side inside the needle portion 142, and the fixed portion 143 of the flexible portion 32 is moved. Be towed. As a result, a contraction force acts on the side of the flexible portion 32 where the fixed portion 143 is provided, and as shown in FIG. 12B, the flexible portion 32 can be bent. Therefore, the puncture portion 31 can be easily directed to the target position for puncture by the hand operation, and the operability is improved.

Also, the proximal shaft does not have to be made of metal. For example, the proximal shaft may be made of resin. In this case, the puncture device has a lead wire for transmitting high frequency energy inside or outside the proximal shaft. The conductor is connected to the proximal shaft 33 and the support 32B. Thereby, the high frequency energy supplied from the external power supply device can be transmitted from the lead wire to the support portion 32B or the puncture portion 31 without going through the proximal shaft.

Hereinafter, examples and comparative examples of the present invention will be described. The puncture devices of Examples 1 and 2 and Comparative Example 1 were prepared, and the sliding resistance when inserted into the dilator was measured.
<Example 1>

A stainless steel pipe having an outer diameter of 0.7 mm, an inner diameter of 0.6 mm, and a length of 15 mm was coated with PTFE having a thickness of 0.05 mm to form a distal inner layer and a distal outer layer of the puncture site. Next, the PTFE at the distal portion of the puncture portion was scraped off with sandpaper and soldered. Furthermore, the shape of the solder was adjusted with sandpaper to make an electrode.

In the flexible portion, the inner layer was formed of high-density polyethylene and the outer layer was formed of polybutylene terephthalate. A stainless steel wire rod was braided between the inner layer and the outer layer to form a support portion. The distal portion of the support was electrically conductive with the distal inner layer (stainless steel pipe) of the puncture site. Further, the proximal portion of the support portion was electrically conducted with the proximal inner layer (stainless steel pipe) of the proximal shaft. The outer diameter of the flexible portion was 1.05 mm, the inner diameter was 0.8 mm, and the length was 50 mm.

A stainless steel pipe having an outer diameter of 1.2 mm, an inner diameter of 0.85 mm, and a length of 680 mm was coated with PTFE having a thickness of 0.05 mm to form a proximal inner layer and a proximal outer layer of the proximal shaft. The puncture portion, the flexible portion and the proximal shaft were joined, and the operation portion was attached to the proximal shaft to prepare the puncture device of Example 1. The needle portion of the puncture device of Example 1 was not bent and had a substantially linear shape.
<Example 2>

After creating the same structure as in Example 1, the distal portion of the proximal shaft was bent at about 30 degrees to make the puncture device of Example 2.
<Comparative Example 1>

The puncture portion of Comparative Example 1 had the same structure as the puncture portion of Example 1. The shaft provided on the proximal side of the puncture portion was formed by covering a stainless steel pipe having an outer diameter of 1.2 mm, an inner diameter of 0.85 mm, and a length of 710 mm with PTFE having a thickness of 0.02 mm. The puncture part and the proximal shaft were joined and the operation part was attached. Further, the distal portion of the proximal shaft was bent at about 45 degrees to prepare the puncture device of Comparative Example 1.
<Sliding test>

A dilator having an outer diameter of 2.7 mm, an inner diameter of 0.9 mm at the distal portion, an inner diameter of 1.31 mm at the proximal portion, and a polypropylene constituent material was prepared. Next, the puncture devices of Examples 1 and 2 and Comparative Example 1 were inserted into the dilator. Then, the electrode was stopped immediately before protruding from the dilator (about 5 mm before the distal opening). After that, the puncture device was moved 45 mm to the distal side with respect to the dilator, and the maximum load (N) and impulse (N · s) were measured. The results are shown in Table 1.

As a result, the maximum load and impulse of Examples 1 and 2 having the flexible portion was lower than the maximum load and impulse of Comparative Example 1. Therefore, it was confirmed that having the flexible portion reduces the sliding resistance of the puncture device to the dilator.

Also, the maximum load and impulse of Example 1 with the proximal shaft bent was lower than the maximum load and impulse of Example 2 with the proximal shaft bent. Therefore, it was confirmed that the sliding resistance of the puncture device to the dilator decreases when the proximal shaft is not bent.

This application is based on Japanese Patent Application No. 2017-041543 filed on March 6, 2017, the disclosure of which is referenced and incorporated as a whole.

1 medical device,
10, 80, 100, 120, 130, 140 puncture device,
20, 90 sheath assembly,
30, 142 Needle part,
31, 112, 122, 132 puncture site,
32, 101, 113, 123, 133 Flexible part,
32A, 126 flexible support,
32B support,
33, 114, 124, 134 Proximal shafts,
34, 112A, 122A, 132A electrodes,
35 side hole,
40, 91 dilator,
46 Dilator bend,
50, 92 outer sheath,
52 Sheath bend,
60 Operation unit,
102 Flexible bend,
115 slit (gap),
116, 127, 137 Cover,
125, 135 Notch (gap),
128, 138 first side,
129, 139 Second side,
141 tow wire,
143 Fixed part,
O Fossa ovalis (living tissue),
L left atrium,
R right atrium.

Claims (9)

A puncture device that is inserted into a tubular elongated body and is used to cauterize living tissue in the living body to form a hole through the elongated body.
A metal puncture site located on the distal side and having conductivity for cauterizing and puncturing living tissue,
With a long proximal shaft located on the proximal side,
It has a flexible portion located between the puncture portion and the proximal shaft and having a flexural rigidity lower than that of the puncture portion and the proximal shaft.
The flexible portion has a support portion having conductivity and a flexible support portion made of resin and having an insulating property .
The proximal shaft is made of a conductive metal, and the proximal shaft, the support portion and the puncture portion are electrically connected to each other .
The support has a clearance that penetrates in the radial direction and is arranged so as to have conductivity between the distal end of the support and the proximal end of the support.
The flexible support portion is a puncture device that enters the gap and closes the gap so as to fill the gap of the support portion . The puncture device according to claim 1, wherein the proximal shaft has a shaft bending portion that bends with respect to a central axis on the proximal side. The puncture device according to claim 1 or 2 , wherein the flexible portion has a flexible bending portion that bends with respect to a central axis on the proximal side. The flexible portion has a first side surface and a second side surface with the central axis interposed therebetween, and the second side surface side of the flexible portion has a smaller force along the axial direction than the first side surface side. The puncture device according to any one of claims 1 to 3 , which is contractible and expandable in the puncture device. A medical device for cauterizing living tissue in a living body to form a hole.
A puncture device for cauterizing and puncturing the biological tissue, and
A tubular dilator into which the puncture device is inserted, and
With a tubular outer sheath into which the dilator is inserted,
The puncture device includes a conductive metal puncture site located on the distal side for puncturing biological tissue, a long proximal shaft located on the proximal side, and the puncture site and the proximal portion. It has a flexible portion located between the shafts that is lower than the flexural rigidity of the puncture portion and the proximal shaft and lower than the flexural rigidity of the sheath assembly in which the dilator is inserted into the outer sheath.
The flexible portion has a support portion having conductivity and a flexible support portion made of resin and having an insulating property .
The proximal shaft is made of a conductive metal, and the proximal shaft, the support portion and the puncture portion are electrically connected to each other .
The support has a clearance that penetrates in the radial direction and is arranged so as to have conductivity between the distal end of the support and the proximal end of the support.
The flexible support portion is a medical device that enters the gap and closes the gap so as to fill the gap of the support portion . The medical device according to claim 5 , wherein the flexural rigidity of the flexible portion is lower than the flexural rigidity of at least one of the dilator and the outer sheath. The medical device of claim 5 or 6 , wherein the proximal shaft has a shaft bend that bends with respect to the proximal central axis. The medical device according to any one of claims 5 to 7 , wherein the flexible portion has a flexible bending portion that bends with respect to a central axis on the proximal side. At least one of the distal portion of the dilator and the distal portion of the outer sheath is bent with respect to the proximal central axis, with the puncture protruding distally from the dilator. The medical device according to any one of claims 5 to 8 , wherein the flexible portion can be positioned inside the site.

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