Transseptal cardiac septum puncture device

Abstract

A cardiac interatrial septum puncture device (1) includes: an elongated core wire (2) having a main body portion (10) and a tip portion (12) thinner than the main body portion (10); an electrode (4) connected to the tip portion (12); a coil (6) covering at least a portion of the tip portion (12) and at least a portion of the main body portion (10) in an axial direction of the core wire (2); and an insulating coating film (8) covering at least a portion of the core wire (2) and at least a portion of the coil (6) in the axial direction.

Description

Technical Field

[0001] This disclosure relates to an atrial septal puncture device. Background Technology

[0002] For the treatment of arrhythmias, a method is known to involve percutaneously inserting an ablation catheter into the left atrium to ablate (cauterize) the pathway of the signal causing the arrhythmia. During ablation in the left atrium, in order to insert the ablation catheter from the right atrium side into the left atrium, a method called atrial septal puncture (Brockenbrough) is sometimes performed, creating a hole in the atrial septum separating the right and left atria. Regarding this atrial septal puncture, for example, Patent Document 1 discloses an atrial septal puncture device that forms a through-hole by applying a high frequency to the atrial septum.

[0003] Patent Document 1: Japanese Patent Publication No. 2016-509942 Summary of the Invention

[0004] The inventors have conducted repeated and in-depth research on atrial septal puncture, and as a result, they came up with a technique that simplifies the atrial septal puncture process.

[0005] This disclosure was made in view of the circumstances and its purpose is to provide a simplified technique for the procedure of seeking atrial septal puncture.

[0006] One aspect of this disclosure is an atrial septal puncture device. This atrial septal puncture device comprises: an elongated core wire having a main body and a tip portion located closer to the tip of the main body and thinner than the main body; an electrode connected to the tip portion; a coil covering at least a portion of the tip portion and at least a portion of the main body in the axial direction of the core wire; and an insulating film covering at least a portion of the core wire and at least a portion of the coil in the axial direction.

[0007] Any combination of the above-mentioned constituent elements, or a scheme transformed from the expression of this disclosure into a method, apparatus, system, etc., is also valid as a scheme of this disclosure.

[0008] According to this disclosure, the procedure for atrial septal puncture can be simplified. Attached Figure Description

[0009] Figure 1 (A) is a side view of the atrial septal puncture device according to the embodiment.

[0010] Figure 1 (B) is the front view of the atrial septal puncture device.

[0011] Figure 2 It is along Figure 1 A sectional view of line AA of (A). Detailed Implementation

[0012] Hereinafter, the present disclosure will be described based on preferred embodiments with reference to the accompanying drawings. These embodiments are not intended to limit the present disclosure but are illustrative; not all features described in the embodiments, or combinations thereof, are necessarily essential features of the present disclosure. Identical or equivalent constituent elements, components, and processes shown in the various drawings are labeled with the same reference numerals, and repeated descriptions are omitted where appropriate. Furthermore, for ease of explanation, the scales and shapes of the parts shown in the figures are set in a convenient manner and are not to be interpreted limitingly unless specifically mentioned. In addition, when terms such as "first" or "second" are used in this specification or claims, unless specifically mentioned, these terms are used to distinguish one component from others and do not indicate any order or importance. Furthermore, in the various drawings, based on the description of the embodiments, parts of less important components are omitted.

[0013] Figure 1 (A) is a side view of the atrial septal puncture device 1 according to the embodiment. Figure 1 (B) is the front view of the atrial septal puncture device 1. Figure 2 It is along Figure 1 A cross-sectional view of line AA in (A). The atrial septal puncture device 1 includes a core wire 2, an electrode 4, a coil 6, and an insulating membrane 8.

[0014] The core wire 2 is a long, elastic, and conductive component that is inserted into the patient's body from the top. Examples of materials used to construct the core wire 2 include stainless steel and Ni-Ti alloy. The length of the core wire 2 is, for example, 1500 mm to 3000 mm.

[0015] Furthermore, the core wire 2 has a main body portion 10 and a top portion 12 located closer to the top end of the main body portion 10. The main body portion 10 and the top portion 12 are continuous with each other. For example, the main body portion 10 and the top portion 12 are integrally formed. In this embodiment, the main body portion 10 extends from the base end of the core wire 2 to the base end of the top portion 12. The top portion 12 extends from the top end of the main body portion 10 to the top end of the core wire 2. The length of the main body portion 10 is, for example, 1400 mm to 2800 mm, and the length of the top portion 12 is, for example, 30 mm to 200 mm.

[0016] The tip portion 12 is thinner than the main body portion 10. In other words, compared to the main body portion 10, the tip portion 12 is thinner along the axial direction of the core wire 2 (in... Figure 1 (A) is the direction indicated by arrow X. The area of ​​the cross section orthogonal to the direction of the core wire 2 is smaller. In this disclosure, "axial direction" refers to the direction of the axis of the core wire 2 when the core wire 2 is extending in a straight line, in other words, the direction of the longitudinal dimension of the core wire 2. Hereinafter, the area of ​​the cross section orthogonal to the axial direction of the core wire 2 will be simply referred to as "cross-sectional area".

[0017] By making the tip portion 12 thinner than the main body portion 10, the flexibility of the tip portion 12 can be improved. As a result, the tip portion 12 is easy to bend, thus allowing for easy and flexible changes in the direction of travel of the atrial septal puncture device 1.

[0018] Furthermore, the tip portion 12 includes a curved portion (not shown) that is bent in a curved shape when no external force is applied. Because the tip portion 12 includes a curved portion, when the atrial septal puncture device 1 punctures the atrial septum to enter the left atrium, the tip of the atrial septal puncture device 1 naturally bends. This prevents the tip of the atrial septal puncture device 1 from contacting the left atrium and damaging it.

[0019] The main body 10 has a cylindrical portion 14. The cylindrical portion 14 is, for example, composed of a circular wire. In this embodiment, the main body 10 is entirely composed of a cylindrical portion 14 with a generally uniform thickness. The core wire 2 has the largest diameter or cross-sectional area in the main body 10. That is, in this disclosure, "the tip portion 12 is thinner than the main body 10" means that the main body 10 has the largest outer diameter portion or the largest cross-sectional area portion of the core wire 2. The diameter of the main body 10 is, for example, about 0.55 mm to 0.90 mm or 0.025 inches to 0.038 inches.

[0020] The top portion 12 has a conical portion 16 and a flat portion 18. The conical portion 16 is, for example, formed of a circular line, extending from the top end of the main body portion 10 to the base end of the flat portion 18. Furthermore, the conical portion 16 has a shape in which the diameter gradually decreases from the base end side of the core line 2 towards the top end side, i.e., a conical shape. It should be noted that the conical portion 16 may also gradually change from a circular line to a flat line from the base end side of the core line 2 towards the top end side. The "shape with gradually decreasing diameter" in this disclosure can also be referred to as "shape with gradually decreasing cross-sectional area".

[0021] The flat portion 18 includes a pair of opposing planes extending from the tip of the cone portion 16 to the tip of the core wire 2. The flat portion 18 is, for example, made of a flat wire. The flat portion 18 restricts the bending direction of the tip portion 12 to the direction in which the two planes of the flat portion 18 face. Therefore, the operation of the atrial septal puncture device 1 is facilitated. Furthermore, the flat portion 18 is positioned on the curved portion of the tip portion 12, and its orientation is determined such that one plane faces inward towards the inside of the curved portion and the other plane faces outward towards the outside of the curved portion. This facilitates bending of the curved portion.

[0022] Electrode 4 is connected to the top end 12. In this embodiment, electrode 4 is fixed to the top end of the core wire 2, i.e., the top end of the flat portion 18. Electrode 4 is made of a highly conductive metal such as copper, stainless steel, platinum, gold, or iridium. Furthermore, electrode 4 is electrically connected to the core wire 2. As an example, electrode 4 is integrally formed with the core wire 2.

[0023] The coil 6 is composed of wire wound into a spiral shape. In this embodiment, the coil 6 is a flat wire coil wound with a flat wire, or it may be a round wire coil wound with a round wire, etc. The coil 6 covers at least a portion of the top end portion 12 and at least a portion of the main body portion 10 in the axial direction of the core wire 2. Therefore, the coil 6 is wound not only at the top end portion 12, but also at the maximum outer diameter portion of the core wire 2.

[0024] Preferably, the coil 6 extends from the top of the top portion 12 to at least the middle of the main body portion 10. In this embodiment, the coil 6 extends from the top of the top portion 12 to the base end of the main body portion 10. For example, the portion of the coil 6 that overlaps with the cylindrical portion 14 is fixed to the cylindrical portion 14 by an adhesive or the like. In the axial direction of the core wire 2, the length of the area of ​​the core wire 2 covered by the coil 6 is preferably 100 mm or more, for example, 1800 mm.

[0025] By covering the tip 12 with coil 6, the difference in thickness between the extended region of the tip 12 and the extended region of the main body 10 in the atrial septal puncture device 1 can be eliminated or at least reduced. That is, the thickness of the atrial septal puncture device 1 can be made more uniform. Therefore, when inserting dilators, sheaths, or other devices into the body along the atrial septal puncture device 1, these devices can be inserted more easily. In particular, when coil 6 extends from the tip of the tip 12 to the base of the main body 10, the thickness of the atrial septal puncture device 1 is more uniform, thus making device insertion easier.

[0026] The coil 6 is highly flexible, thus preventing damage to the flexibility of the tip portion of the atrial septal puncture device 1 even when the tip portion 12 is covered by the coil 6. Furthermore, the coil 6 also covers the main body portion 10 of the core wire 2. Therefore, the basal portion of the atrial septal puncture device 1 is composed of a round wire and the coil 6. This improves the flexibility of the basal portion of the atrial septal puncture device 1 compared to a basal portion of uniform thickness composed solely of a round wire.

[0027] The insulating film 8 covers at least a portion of the core wire 2 and at least a portion of the coil 6 in the axial direction of the core wire 2. In this embodiment, the insulating film 8 extends from the top of the top portion 12 to the middle of the main body portion 10. In the area where the insulating film 8 extends, the insulating film 8 covers the entire circumference of the core wire 2 and the coil 6, that is, the entire circumaxial direction of the core wire 2.

[0028] Therefore, the atrial septal puncture device 1 has a tip conductive portion 20 at the tip and a base conductive portion 22 at the base, with an insulating portion 24 between the tip conductive portion 20 and the base conductive portion 22. An electrode 4, exposed and not covered by the insulating film 8, is disposed on the tip conductive portion 20. A coil 6, also exposed and not covered by the insulating film 8, and the base end of the main body 10 are disposed on the base conductive portion 22. The base conductive portion 22 functions as a terminal for connecting to an external power source (not shown). The axial length of the tip conductive portion 20 and the base conductive portion 22 is, for example, 10 mm.

[0029] The insulating film 8 is made of resin tubing, for example, polytetrafluoroethylene (PTFE), perfluoroalkoxyalkane (PFA), tetrafluoroethylene-hexafluoropropylene copolymer (FEP), polyimide (PI), polyolefin resin, etc., and has insulation and flexibility. The insulating film 8 is fixed to the core wire 2 and coil 6, for example, by crimping. As an example, the insulating film 8 is made of tubing that shrinks upon heating. By heating the insulating film 8 covering the core wire 2 and coil 6 to shrink it, the insulating film 8 is crimped to the core wire 2 and coil 6. The thickness of the insulating film 8 is preferably 0.05 mm or more. This allows for more reliable insulation of the insulating portion 24. As an example, the thickness of the insulating film 8 is the average of the thicknesses at multiple points along the axial direction of the core wire 2.

[0030] In conventional atrial septal puncture, firstly, a guidewire is percutaneously inserted into the inferior vena cava and then through the vessel into the atrial septum. Next, a sheath containing a dilator is inserted along the guidewire into the atrial septum. The guidewire is then withdrawn from the sheath, and the atrial septal puncture device is inserted into the sheath in its place. Next, the atrial septum is compressed through the sheath and dilator; that is, the atrial septum is inflated. In this state, the electrodes of the atrial septal puncture device are pressed against the atrial septum, allowing a high-frequency (RF) current to flow through it. The amount of power supplied to the atrial septum during atrial septal puncture is, for example, 30W to 50W. Assuming an impedance of 1000Ω to 2500Ω, the current flowing through the atrial septum is approximately 110mA to approximately 224mA. This cauterizes the atrial septum, creating a perforation. The atrial septal puncture device is then inserted through the perforation into the left atrium. Next, the dilator is inserted into the through-hole to expand it, and the sheath passes through the through-hole into the left atrium. It should be noted that, of course, the insulating membrane 8 maintains its insulating properties under the aforementioned power or current supply conditions.

[0031] Traditional atrial septal puncture devices had a highly rigid basal portion to facilitate the transmission of force applied by the operator to the terminal electrode. Conversely, traditional guidewires were highly flexible to allow for smooth passage within the blood vessel. Therefore, traditional atrial septal puncture devices were unsuitable for use as guidewires, and vice versa. Consequently, traditional atrial septal punctures required the use of both guidewires and septal puncture devices, inevitably necessitating the exchange of these two devices.

[0032] In contrast, in this embodiment, the base portion of the atrial septal puncture device 1 is composed of a circular wire and a coil 6. This provides the base portion of the atrial septal puncture device 1 with rigidity suitable for use as an atrial septal puncture device, and with flexibility suitable for use as a guidewire. Therefore, the atrial septal puncture device 1 of this embodiment can be used as both a guidewire and an atrial septal puncture device.

[0033] Therefore, the atrial septal puncture procedure using the atrial septal puncture device 1 of this embodiment is as follows: First, the atrial septal puncture device 1 is percutaneously inserted into the inferior vena cava and then inserted into the atrial septum via the blood vessel. Next, a sheath containing a dilator is inserted along the atrial septal puncture device 1 into the atrial septum. Next, the atrial septum is supported by the sheath and the dilator. In this state, the electrode 4 presses against the atrial septum, causing a high-frequency current to flow through it. This burns the atrial septum, forming a through-hole. Then, the atrial septal puncture device 1 passes through the through-hole and enters the left atrium. Next, the dilator is inserted into the through-hole to expand it, and the sheath passes through the through-hole into the left atrium.

[0034] Thus, when using the atrial septal puncture device 1 of this embodiment, the operation of replacing the guidewire with the atrial septal puncture device can be omitted. Therefore, the atrial septal puncture procedure can be simplified.

[0035] The embodiments of this disclosure have been described in detail above. These embodiments are merely examples illustrating specific practices of this disclosure. The content of the embodiments does not limit the technical scope of this disclosure, and various design changes, such as alterations, additions, and deletions of constituent elements, can be made without departing from the spirit of this disclosure as defined in the claims. New embodiments with applied design changes possess the effects of both combined embodiments and variations. In the embodiments, the phrases "in this embodiment" and "in this embodiment" are used to emphasize the possibility of such design changes, but design changes are permitted even without such phrases. Any combination of constituent elements included in each embodiment is valid as a solution of this disclosure. The shading lines in the cross-sectional drawings do not limit the material of the objects marked with shading lines.

[0036] The implementation method can be determined by the following items.

[0037] [First item]

[0038] A septal puncture device (1) comprising:

[0039] The long core wire (2) has a main body (10) and a tip (12) that is located on the top side of the main body (10) and is thinner than the main body (10).

[0040] Electrode (4) is connected to the top part (12);

[0041] The coil (6) covers at least a portion of the top end (12) and at least a portion of the main body (10) along the axial (X) direction of the core wire (2); and

[0042] An insulating film (8) covers at least a portion of the core wire (2) and at least a portion of the coil (6) in the axial direction (X).

[0043] [Second item]

[0044] According to the atrial septal puncture device (1) described in the first item, wherein...

[0045] In the axial direction (X), the length of the area of ​​the core wire (2) covered by the coil (6) is more than 100 mm.

[0046] [Third item]

[0047] According to the atrial septal puncture device (1) described in the first or second item, wherein...

[0048] The top part (12) has a cone (16) whose cross-sectional area orthogonal to the axial direction (X) gradually decreases from the base end side of the core wire (2) toward the top end side.

[0049] [Item 4]

[0050] According to any one of the first to third items, the atrial septal puncture device (1) wherein...

[0051] The top portion (12) has a flat portion (18) comprising a pair of opposing planes.

[0052] [Item 5]

[0053] According to any one of the first to fourth items, the atrial septal puncture device (1) wherein...

[0054] The thickness of the insulating film (8) is 0.05 mm or more.

[0055] Industrial availability

[0056] This invention can be used in atrial septal puncture equipment.

[0057] Explanation of reference numerals in the attached figures

[0058] 1: Atrial septal puncture device; 2: Core wire; 4: Electrode; 6: Coil; 8: Insulating film; 10: Main body; 12: Top part; 14: Cylindrical part; 16: Conical part; 18: Flat part.

Claims

1. An atrial septal puncture device, comprising: A long core wire has a main body and a tip portion that is thinner than the main body and located on the top side of the main body; Electrode, connected to the top end portion; A coil that covers at least a portion of the top end portion and at least a portion of the body portion along the axial direction of the core wire; as well as An insulating film covers at least a portion of the core wire and at least a portion of the coil along the axial direction.

2. The atrial septal puncture device according to claim 1, wherein, In the axial direction, the length of the area of ​​the core wire covered by the coil is 100 mm or more.

3. The atrial septal puncture device according to claim 1 or 2, wherein, The top end has a tapered portion, and the area of ​​the cross section of the tapered portion orthogonal to the axial direction gradually decreases from the base end side of the core wire toward the top end side.

4. The atrial septal puncture device according to claim 1 or 2, wherein, The top portion has a flat portion comprising a pair of opposing planes.

5. The atrial septal puncture device according to claim 1 or 2, wherein, The thickness of the insulating film is 0.05 mm or more.

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