medical devices

Abstract

To provide a medical device capable of inhibiting a state in which an energy transmission part is pressed to a living tissue from being released due to erroneous operation or erroneous activation of an operation part.SOLUTION: A medical device 10 includes: an expansion body 21; a shaft part 31 connected to the expansion body 21; an energy transmission part 22 provided in the expansion body 21; a housing 100 connected to a base end part of the shaft part 31; a displacement shaft 33 for compressing the expansion body 21 in an axial direction; an operation knob 110 for operating the displacement shaft 33 that can be moved from a first position to a third position through a second position with respect to the housing 100; and a locking part 140 for locking the operation knob 110 at the second position. When a release button 141 is pushed in a state that the operation knob 110 is positioned at the second position, the locking of the operation knob 110 is not released, and when the release button 141 is pushed in a state that the operation knob 110 is positioned at the third position, the locking of the operation knob 110 is released and the operation knob can be moved to the first position.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present invention relates to a medical device having an expandable body in which an energy transmission section is disposed to be inserted into a living body and to cauterize living tissue. [Background technology]

[0002] Chronic heart failure is known as a type of heart disease. Chronic heart failure is broadly divided into systolic dysfunction and diastolic dysfunction based on indicators of cardiac function. In patients with diastolic dysfunction, the myocardium becomes enlarged and stiff, causing increased blood pressure in the left atrium and a decrease in the heart's pumping function. This can lead to the patient exhibiting symptoms of heart failure, such as pulmonary edema. There are also heart diseases in which increased blood pressure in the right atrium due to pulmonary hypertension and other conditions can cause the heart's pumping function to decrease, resulting in symptoms of heart failure.

[0003] In recent years, shunt therapy has been attracting attention for these heart failure patients, in which a shunt (a through-hole) is formed in the atrial septum as an escape route for elevated atrial pressure, thereby alleviating the symptoms of heart failure. In shunt therapy, the atrial septum is accessed via a transvenous approach, and a through-hole of a desired size is formed. A medical device for performing such a shunt therapy on the atrial septum is disclosed, for example, in Patent Document 1.

[0004] The medical device described in Patent Document 1 includes two expansion bodies arranged at the tip end of a long shaft, electrodes arranged in the expansion bodies, and an operating unit arranged at the base end of the shaft and capable of operating the two expansion bodies to clamp biological tissue. The electrodes can be supplied with power from a power supply device (console) connectable to the medical device. The surgeon can operate the operating unit to clamp biological tissue between the two expansion bodies and supply power to the electrodes arranged in the expansion bodies to cauterize the clamped biological tissue. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] U.S. Patent Application Publication No. 2020 / 094094 Summary of the Invention [Problem to be solved by the invention]

[0006] If energy is supplied without pressing an energy transmission unit such as an electrode against biological tissue, there is a risk of thrombus formation due to the energy transmission unit being exposed to blood, or of the energy transmission unit damaging an unintended part of the body. Such risks arise not only when the pressing operation is unintentionally or mistakenly omitted, but also when the energy transmission unit is released from its pressed state against the biological tissue due to an incorrect operation or malfunction of the operating unit before or during the output of energy from the energy transmission unit.

[0007] The present invention has been made to solve the above-mentioned problems, and aims to provide a medical device that can prevent the energy transmission unit from being released from its pressed state against biological tissue due to erroneous operation or malfunction of the operating unit. [Means for solving the problem]

[0008] The medical device according to the present invention, which achieves the above object, comprises an expandable body having a central axis and capable of expanding and contracting in a radial direction, a long shaft portion connected to the expandable body, an energy transmission portion provided along the expandable body, a housing connected to a base end of the shaft portion, and a housing for connecting the expandable body to a base end of the shaft portion. The extension A long displacement shaft that compresses in the axial direction, and an axis of the displacement shaft relative to the housing Alongand a locking portion that locks the operating knob at the second position. The expansion body has a recess that is recessed radially inward midway in the axial direction, a first connecting portion connected to the shaft portion, and a second connecting portion connected to the displacement shaft and arranged to face the first connecting portion across the recess in the axial direction. The recess has a distal upright portion, a proximal upright portion, and a bottom portion located radially innermost and arranged between the distal upright portion and the proximal upright portion so as to define a receiving space that can receive biological tissue. The energy transmission portion has the distal upright portion and the proximal upright portion so as to face the receiving space. The displacement shaft is arranged along one of the base-side upright portions, and extends from within the housing along the shaft portion and is connected to the second connecting portion, and is configured to compress the expansion body in the axial direction by moving from an initial position to a compressed position relative to the shaft portion along the axial direction of the expansion body as the operation knob moves from the first position to the second position, and the tip-side upright portion and the base-side upright portion are configured to grasp the biological tissue by displacement of the displacement shaft from the initial position to the compressed position, and the operation knob protrudes from the housing and includes a knob body for moving the operation knob from the first position to the third position, and is movably arranged within the housing, The aforementionedthe locking portion has an action portion connected to the base end of the displacement shaft and displacing the displacement shaft from the initial position to the compressed position as the operation knob is moved, and a first engagement portion displaced together with the action portion, wherein the locking portion is disposed within the housing and has a second engagement portion displaceable between an engagement position where it engages with the first engagement portion of the operation knob located at the second position and a release position where the engagement with the first engagement portion is released, a release button exposed from the housing and for displacing the second engagement portion from the engagement position to the release position, and a flexible deformation portion connecting the release button and the second engagement portion, wherein when the release button is pressed with the operation knob located at the second position, the flexible deformation portion deforms to prevent the second engagement portion engaged with the first engagement portion from displacing from the engagement position to the release position, and when the release button is pressed with the operation knob located at the third position, the second engagement portion displaces from the engagement position to the release position, thereby enabling the engagement between the first engagement portion and the second engagement portion to be released. [Effects of the Invention]

[0009] In the medical device configured as described above, unless the operation knob is moved from the second position to the third position, the second engagement portion cannot be displaced from the engagement position to the release position even if the release button is pressed, and the locking portion that locks the operation knob at the second position cannot be released. Therefore, with the medical device, when the expandable body is compressed to grasp the biological tissue, it is possible to prevent the energy transmission portion from being released from its pressed state against the biological tissue due to an erroneous operation or malfunction of the operation portion before or during the output of energy from the energy transmission portion.

[0010] The flexible deformation portion may have an elongated shape when projected onto a plane including the axis of the displacement shaft and be rotatably disposed within the housing so that the amount of inclination of the flexible deformation portion relative to the axis of the displacement shaft can be changed, the release button and the second engagement portion may be disposed at both ends of the flexible deformation portion in a direction along the axis of the displacement shaft, and pressing the release button may increase the inclination of the flexible deformation portion relative to the axis of the displacement shaft, displacing the second engagement portion from the engagement position to the release position. This allows the second engagement portion to be displaced from the engagement position to the release position by inclining the flexible deformation portion relative to the housing when the release button is pressed. Furthermore, by bending the flexible deformation portion and allowing the flexible deformation portion to absorb the displacement caused by the release button, the second engagement portion may not be displaced from the engagement position to the release position even when the release button is pressed.

[0011] The flexible deformation portion is configured to be in contact with the axis of the displacement shaft midway along the axis of the displacement shaft. and The housing may have a pivot shaft protruding in a perpendicular direction, and the housing may have a bearing for receiving the pivot shaft. Thus, by rotating the flexible deformation portion around the pivot shaft received in the bearing, the action of pressing the release button can be converted into the action of displacing the second engagement portion from the engagement position to the release position.

[0012] The medical device may have a biasing portion elastically deformable along the axis of the displacement shaft so as to bias the first engagement portion of the operation knob located at the second position toward the second engagement portion, whereby the second engagement portion is pressed against the first engagement portion by the biasing force of the biasing portion, thereby preventing the second engagement portion from being displaced from the engaged position to the released position by frictional force.

[0013] The operating portion of the operating knob may be connected to the base end of the displacement shaft via the biasing portion, whereby the force with which the expandable body grips the biological tissue can be appropriately adjusted by the biasing portion, thereby preventing the gripping force from becoming excessive and suppressing damage to the biological tissue.

[0014] The operation knob may have a hook portion engageable with the second engagement portion, and the hook portion may be configured to hook onto the second engagement portion so as to prevent the second engagement portion from displacing from the engagement position to the release position when the operation knob is located at the second position, and to move away from the second engagement portion when the operation knob is located at the third position. This ensures that the hook portion can reliably prevent the second engagement portion from displacing from the engagement position to the release position when the operation knob is located at the second position.

[0015] The hook portion may be a convex portion that protrudes from the first engagement portion toward the second engagement portion, thereby enabling the hook portion, which is a convex portion, to firmly engage with the second engagement portion and to easily detach from the second engagement portion to release the engagement when the operation knob is moved to the third position.

[0016] The operation knob may have a third engagement portion that engages with the second engagement portion when the operation knob is in the first position to prevent the operation knob from moving from the first position to the second position, and the engagement between the second engagement portion and the third engagement portion may be released by pressing the release button. This prevents the operation knob from unintentionally moving from the first position to the second position due to an erroneous operation or malfunction. This prevents the expansion body from unintentionally expanding, improving safety. Furthermore, it prevents the expansion body, which is contractible when the operation knob is in the first position, from being inhibited by unintentional movement of the displacement shaft toward the proximal end, improving safety.

[0017] The first connecting portion of the expansion body is located closer to the base end than the second connecting portion, and the displacement shaft is configured to compress the expansion body in the axial direction by pulling the second connecting portion in the base end direction as the expansion shaft moves from the initial position to the compressed position located closer to the base end than the initial position, and the operation knob moves the displacement shaft from the initial position to the compressed position as the operation knob moves from the first position to the second position located closer to the base end than the first position, and the first engaging portion is configured to connect the operating portion to the axial line of the displacement shaft. and a first protrusion that protrudes in a direction perpendicular to the axis of the displacement shaft and includes a tip end surface, and the second engagement portion is configured to be extended from the flexible deformation portion to the axis of the displacement shaft so as to engage with the tip end surface of the first protrusion. and Alternatively, the second protrusion may protrude perpendicularly to the first protrusion. This allows the second protrusion on the locking portion to engage with the tip surface of the first protrusion on the operating knob that has moved from the first position to the second position to compress the expandable body, thereby effectively maintaining the expandable body in a compressed state.

[0018] The first convex portion has an inclined surface that is inclined so that the amount of protrusion from the action portion gradually decreases toward the base end of the first convex portion, and the tip surface of the first convex portion is aligned with the axis of the displacement shaft. Hanging the second engaging portion is a straight surface, and the second engaging portion is engaged with the tip surface of the first convex portion along the axis of the displacement shaft. Hanging The first protrusion may have a straight base end surface. This allows the inclined surface of the first protrusion to come into contact with the second engagement portion and smoothly move over the second engagement portion when the operating knob moves from the first position to the second position, and when the operating knob reaches the second position, the tip surface of the first protrusion engages with the second engagement portion, preventing the operating knob from returning to the first position. [Brief explanation of the drawings]

[0019] [Figure 1] 1 is a side view illustrating an overall configuration of a medical system according to an embodiment of the present invention. [Figure 2] FIG. 1 is a side view showing the distal end of a medical device. [Figure 3]3A and 3B are diagrams showing the inside of the operating unit before the operating knob is operated, in which (A) is a longitudinal cross-sectional view and (B) is a cross-sectional view taken along line AA in FIG. 3A. [Figure 4] FIG. [Figure 5] 10A and 10B are longitudinal cross-sectional views showing the inside of the operating unit, in which (A) shows the state where the operating knob has started to move from the first position toward the base end, (B) shows the state where the operating knob has reached the second position, and (C) shows the state where the release button has been pressed with the operating knob in the second position. [Figure 6] 10A and 10B are longitudinal cross-sectional views showing the inside of the operation unit, in which (A) shows the state in which the operation knob has been moved to the third position and the release button has been pressed, and (B) shows the state in which the operation knob has been returned to the first position. [Figure 7] FIG. 10 is a schematic diagram showing a state in which an expandable body is placed in a through-hole in the atrial septum. [Figure 8] FIG. 10 is a cross-sectional view showing the state in which the balloon is inserted into the atrial septum. [Figure 9] FIG. 10 is a cross-sectional view showing the state in which the tip of the medical device is inserted into the atrial septum. [Figure 10] FIG. 10 is a cross-sectional view showing the state in which the expansion body is placed in the atrial septum. [Figure 11] 10 is a cross-sectional view showing a state in which the energy transmission section placed in the recess of the expandable body is in close contact with biological tissue. FIG. [Figure 12] 10 is a flowchart illustrating a method of using the medical system. [Figure 13] 10A and 10B are longitudinal cross-sectional views of the inside of the operation unit in the first modified example, where (A) shows the operation knob in the second position, and (B) shows the operation knob in the third position with the release button pressed. [Figure 14] 10A and 10B are plan views showing the distal end of a medical device in a second modified example, where (A) shows the state before the expandable body grasps the biological tissue, and (B) shows the state after the biological tissue has been grasped by the expandable body. DETAILED DESCRIPTION OF THE INVENTION

[0020] Hereinafter, embodiments of the present invention will be described with reference to the drawings. Note that the dimensional ratios in the drawings may be exaggerated for convenience of explanation and may differ from the actual ratios. Furthermore, in this specification, the side of the medical device 10 that is inserted into a body cavity will be referred to as the "distal side," and the side that is operated will be referred to as the "proximal side." Furthermore, in this specification, the range "X to Y" includes X and Y and means "X or more and Y or less."

[0021] As shown in Figure 7, the medical device 10 of this embodiment is configured to be able to perform a maintenance procedure to maintain the size of the through-hole Hh formed in the atrial septum HA, which is the biological tissue of the patient's heart H, and expanded by a balloon.

[0022] As shown in FIGS. 1 and 2, the device according to this embodiment is a medical device 10 that is inserted into a living body to cauterize living tissue, and is operated by receiving power from a power supply device 190.

[0023] The medical device 10 has a long portion 20 extending from the base end to the tip, an extension body 21 provided at the tip of the long portion 20, an energy transmission portion 22 having multiple electrodes 24 provided along the extension body 21, an operating portion 23 connected to the base end of the long portion 20, a connection terminal 27 connectable to a power supply unit 190, and a connection cable 25 extending from the operating portion 23 to the connection terminal 27.

[0024] The long portion 20 has a shaft portion 31 that holds the expansion body 21 at its tip, an outer tube 30 that houses the shaft portion 31, a displacement shaft 33, and a traction portion 35 that is fixed to the tip of the displacement shaft 33.

[0025] The shaft portion 31 is a long tubular body extending from the operation portion 23 to the expansion body 21. The base end of the shaft portion 31 is fixed to the tip end of the operation portion 23. The tip end of the shaft portion 31 is fixed to the base end of the expansion body 21.

[0026] The outer tube 30 is a long tubular body that covers the shaft portion 31 and is movable back and forth in the axial direction (toward the axis of the long portion 20) relative to the shaft portion 31. When the outer tube 30 is moved toward the distal end of the long portion 20, it can house the expandable body 21, which has been contracted radially, inside it. The radial direction is the direction perpendicular to the axis of the shaft portion 31. By moving the outer tube 30 toward the proximal end from a state in which the expandable body 21 is housed, the surgeon can expose the expandable body 21 from the outer tube 30 and expand it radially.

[0027] The displacement shaft 33 is a long tubular body disposed inside the shaft portion 31 and is movable back and forth in the axial direction relative to the shaft portion 31. The displacement shaft 33 protrudes distally from the distal end of the shaft portion 31 and protrudes distally from the distal end of the expansion body 21. The distal end of the displacement shaft 33, which is located distally of the expansion body 21, is fixed to the traction unit 35. The proximal end of the displacement shaft 33 is extended proximally beyond the operation unit 23. A guidewire lumen is formed inside the displacement shaft 33 along the axial direction, through which a guidewire 11 (see FIGS. 8 to 10) can be inserted. The displacement shaft 33 can be displaced from an initial position (see FIG. 3) to a compressed position (see FIG. 5(B)) relative to the shaft portion 31 along the axial direction of the expansion body 21, thereby compressing the expansion body 21 in the axial direction.

[0028] The traction portion 35 is an annular member fixed to the outer peripheral surface of the tip of the displacement shaft 33, and protrudes radially outward from the outer peripheral surface of the displacement shaft 33. The traction portion 35 is not fixed to the expansion body 21. The outer diameter of the traction portion 35 is larger than the inner diameter of the tip of the expansion body 21. Therefore, the traction portion 35 abuts against the tip of the expansion body 21 from the tip side and pulls the expansion body 21 toward the base end, thereby applying a compressive force to the expansion body 21 that compresses it along the axial direction of the shaft portion 31.

[0029] As shown in Figures 1, 3 and 4, the operating unit 23 has a housing 100 that is held by the surgeon, an operating knob 110 that the surgeon can move along the axis of the displacement shaft 33, a biasing unit 120 that transmits the movement of the operating knob 110 to the displacement shaft 33, a locking unit 140 that locks the operating knob 110 in a predetermined position, an electric wire 160 that transmits power from a power supply device 190 to the electrode 24, and a shaft connecting unit 180 that connects the shaft unit 31 to the housing 100.

[0030] The housing 100 has a guide rail 101 that holds the operation knob 110 so that it can slide linearly along the axis of the displacement shaft 33, a knob opening 102 that exposes a portion of the operation knob 110 to the outside, a button opening 103 that exposes a release button 141 provided on the locking section 140 to the outside, and a bearing section 104 to which the locking section 140 is rotatably connected. The knob opening 102 and the button opening 103 open in a direction substantially perpendicular to the axis of the displacement shaft 33. The knob opening 102 is formed with a size that allows the operation knob 110 to move along the axis of the displacement shaft 33. The button opening 103 is located on the tip side of the knob opening 102.

[0031] The operation knob 110 is disposed slidably along the axis of the displacement shaft 33 relative to the housing 100. The operation knob 110 can move the displacement shaft 33 from the initial position to the compressed position by moving from a first position (see FIG. 3) to a second position (see FIG. 5(B)) that is closer to the base end than the first position. The operation knob 110 can further move from the second position to a third position (see FIG. 6(A)) that is closer to the base end than the second position. The operating knob 110 has a knob body 111 exposed to the outside from a knob opening 102 in the housing 100 so that it can be operated by the surgeon, an operating part 114 that is movably arranged within the housing 100 and connected to the base end of the displacement shaft 33, and that displaces the displacement shaft 33 from its initial position to its compressed position as the operating knob 110 is moved, a sliding part 112 that makes linear sliding contact with the guide rail 101 inside the housing 100 along the axis of the displacement shaft 33, and a stopper 115 that can abut against the base end surface of a ring-shaped fixing member 170 fixed to the displacement shaft 33.

[0032] The operating knob 110 further has a first engagement portion 116 and a third engagement portion 117 that can engage with a second engagement portion 142, which will be described in detail after the lock portion 140. The first engagement portion 116 and the third engagement portion 117 are displaced together with the knob body 111 and the action portion 114, and the first engagement portion 116 is located closer to the tip than the third engagement portion 117.

[0033] The first engagement portion 116 is a first convex portion 116A that protrudes from the action portion 114 in a direction approximately perpendicular to the axis of the displacement shaft 33 and includes a tip surface 116B and an inclined surface 116C. The tip surface 116B is a surface that is approximately perpendicular to the axis of the displacement shaft 33. The inclined surface 116C is inclined so that the amount of protrusion from the action portion 114 gradually decreases toward the base end of the first convex portion 116A.

[0034] The third engagement portion 117 is disposed closer to the base end than the first engagement portion 116 along the axis of the displacement shaft 33. The third engagement portion 117 is a third convex portion 117A that protrudes from the action portion 114 in a direction approximately perpendicular to the axis of the displacement shaft 33 and includes a base end surface 117B and an inclined surface 117C. The base end surface 117B is a surface that is approximately perpendicular to the axis of the displacement shaft 33. The inclined surface 117C is inclined so that the amount of protrusion from the action portion 114 gradually decreases toward the tip of the third convex portion 117A.

[0035] The acting portion 114 is a portion that applies a traction force in the proximal direction to the displacement shaft 33 via the biasing portion 120. Because the acting portion 114 is connected to the proximal end of the displacement shaft 33 via the biasing portion 120, when the operation knob 110 moves from the first position to the second position along the axial direction of the displacement shaft 33, the acting portion 114 presses the displacement shaft 33 via the biasing portion 120, and can move the displacement shaft 33 from the initial position to the compressed position. Furthermore, the acting portion 114 can move from the second position to the third position toward the proximal end while resisting the biasing force of the biasing portion 120.

[0036] The stopper 115 is disposed closer to the base end than the action portion 114. The stopper 115 abuts against the base end surface of a fixing member 170 fixed to the displacement shaft 33, thereby restricting the displacement shaft 33 from moving more than necessary in the base end direction relative to the operation knob 110.

[0037] As shown in Figures 3 and 4, the locking portion 140 has a release button 141 that can be pressed by the surgeon, a second engagement portion 142 that can engage with the first engagement portion 116 and the third engagement portion 117, a flexible deformation portion 143 that connects the release button 141 and the second engagement portion 142, and a rotating shaft portion 144 that is rotatably connected to the housing 100.

[0038] The release button 141 is located at the tip of the locking portion 140, and is exposed from the inside of the housing 100 to the outside through the button opening 103 of the housing 100. The release button 141 may be biased from the inside of the housing 100 to the outside by a spring member or the like (not shown).

[0039] The second engagement portion 142 is located at the base end of the locking portion 140, and is disposed inside the housing 100. When the release button 141 is pressed, the locking portion 140 rotates around the rotation shaft portion 144, and the second engagement portion 142 is movable in a direction substantially perpendicular to the axis of the displacement shaft 33.

[0040] The flexible deformation portion 143 has an elongated shape when projected onto a plane including the axis of the displacement shaft 33, is flexible, and is rotatably disposed within the housing 100 so that the amount of inclination relative to the axis of the displacement shaft 33 can be changed. The release button 141 and the second engagement portion 142 are disposed on both ends of the flexible deformation portion 143 in the direction along the axis of the displacement shaft 33. When the release button 141 is pressed by the surgeon, the flexible deformation portion 143 rotates so that the inclination relative to the axis of the displacement shaft 33 can be changed (see FIGS. 5(A) and 6(A)).

[0041] The pivot shaft 144 protrudes from the flexible deformation portion 143 between the release button 141 and the second engagement portion 142 in a direction perpendicular to the axis of the displacement shaft 33 and perpendicular to the direction in which the second engagement portion 142 and the release button 141 can be displaced. The pivot shaft 144 is rotatably held by a bearing portion 104 formed in the housing 100. When the surgeon presses the release button 141 exposed from the button opening 103, the lock portion 140 pivots about the pivot shaft 144, the release button 141 is pushed into the button opening 103, and the second engagement portion 142 moves from the release position to the displacement position (see FIGS. 5(A) and 6(A)).

[0042] When the release button 141 is pressed and the locking portion 140 is rotated, the second engagement portion 142 can be displaced in a direction substantially perpendicular to the axis of the displacement shaft 33. As shown in FIG. 3A, the second engagement portion 142 is disposed on the proximal side of the proximal end surface 117B of the third engagement portion 117 of the operation knob 110 when the operation knob 110 is positioned at the first position, and is spaced a small distance from the proximal end surface 117B. When the release button 141 is not pressed and the operation knob 110 moves from the first position toward the proximal end, the second engagement portion 142 comes into contact with the proximal end surface 117B of the third engagement portion 117 of the operation knob 110, thereby preventing the operation knob 110 from moving toward the proximal end.

[0043] In addition, the second engagement portion 142 can be displaced between an engagement position where it can engage with the tip surface 116B of the first engagement portion 116 of the operating knob 110 located in the second position, as shown in Figure 5(B), and a release position where it is disengaged from the first engagement portion 116, as shown in Figure 6(A).

[0044] As shown in FIG. 3 , the biasing portion 120 is disposed between the operation knob 110 and the displacement shaft 33 to adjust the traction force transmitted from the operation knob 110 to the displacement shaft 33. The biasing portion 120 is a coil spring disposed to surround the displacement shaft 33. The biasing portion 120 is elastically expandable and contractible along the axial direction of the displacement shaft 33. The tip of the biasing portion 120 is capable of abutting against the base end surface of the action portion 114 of the operation knob 110. The base end of the biasing portion 120 is capable of abutting against the tip surface of a fixing member 170 fixed to the displacement shaft 33.

[0045] As shown in Figures 1 and 3, the electric wire 160 has a connection electric wire portion 165 that extends from a connection terminal 27 that can be connected to a power supply device 190 through a connection cable 25 to the inside of the housing 100, and an electric wire main body portion 162 that is connected to the connection electric wire portion 165 inside the housing 100 and extends along the shaft portion 31 to the energy transmission portion 22.

[0046] 3, the shaft connecting portion 180 has a holding portion 181 that is fixedly held inside the housing 100, and a seal member 182 that is arranged inside the holding portion 181. The holding portion 181 is a substantially cylindrical member that is connected in close contact with the base end of the shaft portion 31. The seal member 182 is an annular member that is arranged inside the holding portion 181 on the base end side of the shaft portion 31 and that slidably contacts the outer circumferential surface of the displacement shaft 33. The seal member 182 prevents blood and the like from flowing into the housing 100 from between the shaft portion 31 and the displacement shaft 33.

[0047] As shown in Figures 1 and 2, the expansion body 21 has a force receiving portion 51 arranged at the tip of the expansion body 21, a base end connecting portion 52 arranged at the base end of the expansion body 21, a second connecting portion 53 connected to the force receiving portion 51, a first connecting portion 54 connected to the base end connecting portion 52, and a recess 55 arranged between the second connecting portion 53 and the first connecting portion 54.

[0048] The force receiving portion 51 is annular and can receive a force directed toward the base end from the traction portion 35 arranged on the tip side. The base end connecting portion 52 is annular and is fixed to the tip end of the shaft portion 31.

[0049] The second connecting portion 53 is flexibly deformable and has a distal-side expanding portion 56 that extends radially outward from the force-receiving portion 51 toward the proximal end, and a distal-side apex portion 57 that is disposed on the proximal side of the distal-side expanding portion 56 and curves convexly outward in the radial direction.

[0050] The second connecting portion 53 has a plurality of distal strut structures 60 that extend radially outward from the force-receiving portion 51 toward the base end and form the distal expansion portion 56. The plurality of distal strut structures 60 are arranged at approximately equal intervals in the circumferential direction of the expandable body 21 when expanded.

[0051] Each of the multiple tip-side strut structures 60 has a first strut 61 extending from the force-receiving portion 51 toward the base end, and a second strut 62 extending from the base end of the first strut 61 toward the base end and connected to the tip-side apex 57.

[0052] Each first strut 61 extends from the force-receiving portion 51 substantially parallel to the axis of the expandable body 21 when viewed from the outside in the radial direction. Each second strut 62 branches into two branches extending in the circumferential direction of the expandable body 21 while moving from the base end of the respective first strut 61 toward the base end, and joins at a first junction 65 or a second junction 66. The first junctions 65 and second junctions 66 are arranged alternately at approximately equal intervals in the circumferential direction of the expandable body 21 when expanded.

[0053] Each first junction 65 is connected to a distal apex 57 that is arranged in the same phase as the electrode 24 in the circumferential direction of the expandable body 21. Each second junction 66 is connected to a distal apex 57 that is arranged in a different phase from the electrode 24 in the circumferential direction of the expandable body 21.

[0054] The first connecting portion 54 is flexibly deformable and has a base-end expanding portion 58 that extends radially outward from the base-end connecting portion 52 toward the tip, and a base-end apex portion 59 that is disposed distal to the base-end expanding portion 58 and curves convexly outward in the radial direction.

[0055] The proximal expansion section 58 has multiple proximal strut structures 90. Each proximal strut structure 90 and the multiple electrode placement sections 81 are arranged in the same phase in the circumferential direction of the expandable body 21. Each of the multiple proximal strut structures 90 has multiple third struts 91 extending from the tip of the shaft section 31 to the proximal apex 59, approximately parallel to the axis of the expandable body 21 when viewed from the outside in the radial direction, and multiple secondary struts 92 connecting adjacent third struts 91 in the circumferential direction. Each secondary strut 92 is connected to two adjacent third struts 91 in the circumferential direction. Each secondary strut 92 is curved. Therefore, even if the distance between two adjacent third struts 91 increases when the expandable body 21 expands, the secondary struts 92 can continue to support the two third struts 91 while deforming into a shape close to a straight line. Therefore, the expansion body 21 can be expanded by the compressive force applied by the displacement shaft 33 while spreading the third struts 91 at approximately equal intervals.

[0056] The recess 55 is flexibly deformable. When the expandable body 21 is expanded, the recess 55 is recessed radially inward and extends to connect the base end apex 59 and the tip end apex 57. The recess 55 defines a receiving space 74 that can receive biological tissue when the expandable body 21 is expanded.

[0057] The recess 55 has a bottom portion 71 located at the radially innermost position, a tip-side upright portion 72 extending radially outward from the tip of the bottom portion 71 to the tip-side apex 57, and a base-side upright portion 73 extending radially outward from the base end of the bottom portion 71 to the base-side apex 59.

[0058] It is preferable that the distance between the base-side upright portion 73 and the tip-side upright portion 72 is somewhat larger in the axial direction on the outer side than on the inner side in the radial direction when the expansion section is expanded. This makes it easy to place biological tissue between the base-side upright portion 73 and the tip-side upright portion 72 from the outer side in the radial direction.

[0059] The recess 55 has a plurality of recessed strut structures 80 arranged circumferentially. Each of the plurality of recessed strut structures 80 has a plurality of electrode placement portions 81 arranged on the base-end side upright portion 73, a plurality of opposing portions 82 arranged on the tip-end side upright portion 72, and a plurality of bottom connecting portions 83 on the bottom 71 that connect pairs of electrode placement portions 81 and opposing portions 82.

[0060] The multiple electrode placement sections 81 are arranged at approximately equal intervals in the circumferential direction of the expansion body 21. The multiple opposing sections 82 are arranged at approximately equal intervals in the circumferential direction of the expansion body 21. The multiple bottom connecting sections 83 are arranged at approximately equal intervals in the circumferential direction of the expansion body 21.

[0061] Each of the facing portions 82 faces a corresponding one of the electrodes 24 when the expandable body 21 is expanded. Each of the facing portions 82 has a plurality of bifurcated distal-side standing struts 84 that branch out from the distal end of each of the bottom connecting portions 83 toward the distal end, generally along the circumferential direction of the expandable body 21, and a plurality of back support portions 85. The back support portions 85 connect the two distal-side standing struts 84 that branch out from each of the bottom connecting portions 83. The back support portions 85 are arranged side by side from the side closer to the bottom 71 to the side closer to the distal apex 57. Each of the back support portions 85 is curved so that the portion between the ends connected to the two distal-side standing struts 84 protrudes toward the distal apex 57. The side of each of the back support portions 85 closer to the distal apex 57 is easily bent, with the ends connected to the distal-side standing struts 84 as fulcrums. Therefore, the back support portion 85 can bend due to a force acting toward the distal end from the electrode 24 arranged on the base-side standing portion 73. Therefore, the biological tissue sandwiched between the electrode 24 and the back support portion 85 can be brought into close contact with the electrode 24. Of the multiple back support portions 85 forming each opposing portion 82, the back support portion 85 closest to the distal end apex 57 is connected to the distal end apex 57 at a portion that protrudes toward the distal end apex 57. The number of back support portions 85 forming each opposing portion 82 is not particularly limited.

[0062] The energy transfer unit 22 has a plurality of electrodes 24. Each electrode 24 is arranged on a surface that forms the inside of the recess 55 of each electrode placement unit 81. The electrode 24 is arranged in close contact with the surface that forms the inside of the recess 55 of the electrode placement unit 81. At least a portion of the electrode 24 has a surface that faces the receiving space 74 when expanded, and has a convex curved shape. Note that the surface of the electrode 24 that faces the receiving space 74 when expanded may also have a flat shape.

[0063] When the expandable body 21 is expanded, the electrode 24 is disposed on the surface of the base-side upright portion 73 facing the distal end. Because the electrode 24 is provided on the base-side upright portion 73, when the recess 55 clamps the atrial septum HA, energy from the electrode 24 is transmitted to the atrial septum HA from the right atrium side. Note that if the electrode 24 were provided on the distal upright portion 72, energy from the electrode 24 would be transmitted to the atrial septum HA from the left atrium side.

[0064] The electrodes 24 are configured, for example, as bipolar electrodes that receive power from a power supply device 190. In this case, electricity is passed between the electrodes 24 arranged in each electrode arrangement portion 81.

[0065] Alternatively, the electrode 24 may be configured as a monopolar electrode. In this case, electricity is passed between the electrode 24 and a return electrode plate prepared outside the body. The electrode 24 may also be a heat-generating element (electrode tip) that generates heat by receiving high-frequency electrical energy from an energy supply device. Furthermore, the energy transmission unit 22 can be configured with an energy transmission element that can apply energy to the puncture hole Hh, such as microwave energy, ultrasonic energy, coherent light such as a laser, a heated fluid, a cooled fluid, a device that exerts a heating or cooling effect using a chemical medium, a device that generates frictional heat, a heater equipped with an electric wire, etc., and the specific form is not particularly limited.

[0066] In this embodiment, the electrode 24 is provided on the base end standing portion 73 and the back support portion 85 is provided on the tip end standing portion 72, but the electrode 24 may also be provided on the tip end standing portion 72 and the back support portion 85 may also be provided on the base end standing portion 73.

[0067] In this embodiment, the operating knob 110, the biasing section 120, the displacement shaft 33 and the traction section 35, which can move the tip of the expansion body 21, and the housing 100 and the shaft section 31, which can move the base end of the expansion body 21, function as a displacement mechanism 26 that compresses the expansion body 21 in the axial direction by displacing the base end of the expansion body 21 relative to the tip of the expansion body 21 approximately along the central axis.

[0068] The expandable body 21 is formed integrally, for example, by cutting out from a cylinder. The struts forming the expandable body 21 may have a thickness of 50 to 500 μm and a width of 0.3 to 2.0 mm, for example. However, the struts forming the expandable body 21 may have dimensions outside these ranges. Furthermore, the shape of the struts is not particularly limited, and may have, for example, a circular cross-sectional shape or other cross-sectional shapes.

[0069] The expandable body 21 can be made of a metal material. Examples of such metal materials include titanium alloys (Ti-Ni, Ti-Pd, Ti-Nb-Sn, etc.), copper alloys, stainless steel, β-titanium steel, and Co-Cr alloys. It is preferable to use alloys with spring properties, such as nickel-titanium alloys. However, the material of the wire portion is not limited to these, and other materials may also be used.

[0070] The outer cylinder 30 and shaft portion 31 of the long portion 20 are preferably formed from a material having a certain degree of flexibility. Examples of such materials include polyolefins such as polyethylene, polypropylene, polybutene, ethylene-propylene copolymer, ethylene-vinyl acetate copolymer, ionomer, and mixtures of two or more of these, soft polyvinyl chloride resin, polyamide, polyamide elastomer, polyester, polyester elastomer, polyurethane, fluororesins such as polytetrafluoroethylene, polyimide, PEEK, silicone rubber, and latex rubber.

[0071] The displacement shaft 33 and the traction section 35 can be formed from a long wire rod made of, for example, a superelastic alloy such as a nickel-titanium alloy or a copper-zinc alloy, a metal material such as stainless steel, a resin material with relatively high rigidity, etc. Alternatively, the above may be coated with a resin material such as polyvinyl chloride, polyethylene, polypropylene, an ethylene-propylene copolymer, or a fluororesin.

[0072] Next, a description will be given of the power supply device 190. The power supply device 190 has a power output unit 191, a notification unit 192, and a control unit 193, as shown in FIG.

[0073] The power output unit 191 is a part that outputs power for performing maintenance treatment to the connection terminal 27 of the medical device 10. The power output unit 191 is controlled by the control unit 193 and can output high-frequency current at any power for any time.

[0074] The notification unit 192 is a component that notifies the operator of the control status, warnings, and the like. The notification unit 192 is, for example, a speaker that notifies by sound or an image monitor that notifies by image. The display method of the image monitor and the output method by the speaker are not particularly limited. The notification unit 192 may not be configured in the power supply device 190, but may be an external device that is communicably connected to the power supply device 190.

[0075] The control unit 193 is configured with a CPU (Central Processing Unit), a storage circuit, and an operation program. Interfaces such as a keyboard and a mouse may be connected to the control unit 193. The control unit 193 is, for example, a computer.

[0076] The control unit 193 controls the power output unit 191, and can control the output of high-frequency current from the power output unit 191. The control unit 193 can cause the power output unit 191 to output any desired power for any desired time.

[0077] Next, a method of using the medical device 10 according to this embodiment will be described with reference to the flowchart shown in Fig. 12. This method is performed on a patient suffering from heart failure (left ventricular failure). More specifically, as shown in Fig. 7, this is a treatment method performed on a patient suffering from chronic heart failure in which the blood pressure in the left atrium HLa increases due to hypertrophy of the myocardium of the left ventricle of the heart H and increased stiffness.

[0078] The method of using the medical device 10 of this embodiment includes the steps of: forming a through-hole Hh in the atrial septum HA (S1); placing an expansion body 21 in the through-hole Hh (S2); receiving biological tissue in the receiving space 74 (S3); checking hemodynamics near the through-hole Hh (S4); grasping the through-hole Hh with the expansion body 21 (S5); performing maintenance treatment to maintain the size of the through-hole Hh (S6); and checking hemodynamics near the through-hole Hh after the maintenance treatment has been performed (S7).

[0079] When forming the through-hole Hh, the surgeon delivers an introducer, which is a combination of a guiding sheath and a dilator, to the vicinity of the interatrial septum HA. The introducer can be delivered to the right atrium HRa, for example, via the inferior vena cava IV. The introducer can also be delivered using a guidewire 11. The surgeon can insert the guidewire 11 into the dilator and deliver the introducer along the guidewire 11. The insertion of the introducer and the guidewire 11 into the living body can be performed by a known method, such as using an introducer for introducing blood vessels.

[0080] In step S1, the surgeon passes a puncture device (not shown) from the right atrium HRa side toward the left atrium HLa side to form a through-hole Hh in the fossa ovalis of the interatrial septum HA. For example, a device such as a sharp-tipped wire can be used as the puncture device. The puncture device is inserted through a dilator and delivered to the interatrial septum HA. After removing the guidewire 11 from the dilator, the puncture device can be delivered to the interatrial septum HA in place of the guidewire 11.

[0081] Next, the surgeon delivers the balloon catheter 250 to the vicinity of the atrial septum HA along the pre-inserted guide wire 11. As shown in Fig. 8, the balloon catheter 250 has a balloon 252 at the distal end of the shaft portion 251. Once the balloon 252 is positioned in the atrial septum HA, it is expanded radially to expand the through-hole Hh.

[0082] In step S2, as shown in FIG. 9, the medical device 10 is delivered near the atrial septum HA along the pre-inserted guidewire 11. At this time, the distal end of the medical device 10 penetrates the atrial septum HA and reaches the left atrium HLa. During insertion of the medical device 10, the expandable body 21 is housed in the outer tube 30. The medical device 10 may also be a device without the outer tube 30. In this case, a sheath corresponding to the outer tube 30 is separately prepared, and in step S2, the sheath is delivered in advance near the atrial septum HA along the guidewire 11 so that the distal end of the sheath reaches the left atrium HLa through the through-hole Hh in the atrial septum HA. Next, the expandable body 21 of the medical device 10 is inserted into the sheath from its proximal end, and the distal end of the expandable body 21 is delivered into the left atrium HLa through the through-hole Hh in the atrial septum HA, as in FIG. 9.

[0083] Next, in step S3, the expandable body 21 is exposed by moving the outer tube 30 toward the proximal end. As a result, as shown in FIG. 10 , the expandable body 21 expands in diameter, the recess 55 is positioned in the through-hole Hh in the atrial septum HA, and the receiving space 74 receives the biological tissue surrounding the through-hole Hh. In this state, the operation knob 110 is located in the first position, as shown in FIGS. 3 and 4 . The second engagement portion 142 of the locking portion 140 is located on the proximal side of the proximal end surface 117B of the third engagement portion 117 of the operation knob 110. Therefore, if the operation knob 110 moves from the first position toward the proximal end due to an erroneous operation or malfunction, the second engagement portion 142 of the locking portion 140 comes into contact with the proximal end surface 117B of the third engagement portion 117 of the operation knob 110, preventing the operation knob 110 from moving toward the proximal end. This prevents the expandable body 21 from erroneously grasping biological tissue due to an erroneous operation or malfunction of the operating unit 23. Note that in step S1, when the through-hole Hh is expanded by the balloon 252, the through-hole Hh may not be expanded evenly in the radial direction and may become slit-shaped. In this case, when the expandable body 21 is expanded in diameter to receive the biological tissue surrounding the through-hole Hh into the receiving space 74, the expandable body 21 expands the through-hole Hh in a direction different from the direction in which the slit extends.

[0084] Once the biological tissue surrounding the through-hole Hh is received in the receiving space 74, hemodynamics is confirmed in step S4. As shown in FIG. 7, the surgeon delivers the hemodynamic confirmation device 200 to the right atrium HRa via the inferior vena cava IV. For example, a known echo catheter can be used as the hemodynamic confirmation device 200. The surgeon can display an echo image acquired by the hemodynamic confirmation device 200 on a display or other display device and confirm the amount of blood passing through the through-hole Hh based on the displayed image. If the amount of blood passing through the through-hole Hh does not reach the desired amount, the surgeon moves the outer tube 30 toward the distal end to store the expandable body 21 inside the outer tube 30, and then removes the expandable body 21 together with the outer tube 30 from the through-hole Hh. Next, the through-hole Hh is expanded again using a balloon catheter having a balloon with a larger expansion diameter than the balloon 252 used in step S1, and the process returns to step S2.

[0085] In step S5, the surgeon presses the release button 141 with the atrial septum HA received in the receiving space 74 of the recess 55. As a result, as shown in FIG. 5(A), the locking portion 140 rotates about the rotation shaft portion 144, and the second engagement portion 142 moves from the engagement position to the release position. Next, the surgeon moves the knob main body 111 toward the base end relative to the housing 100. At this time, because the second engagement portion 142 is in the release position, the base end surface 117B of the third engagement portion 117 of the operating knob 110 does not come into contact with the second engagement portion 142 of the locking portion 140. Therefore, the operating knob 110 can be moved from the first position toward the base end.

[0086] After the third engagement portion 117 passes the second engagement portion 142 toward the proximal end, the operator can release the depression of the release button 141. Then, when the operator moves the knob body 111 further toward the proximal end relative to the housing 100, the inclined surface 116C of the first engagement portion 116 comes into contact with the second engagement portion 142 of the locking portion 140. The inclined surface 116C can push and move the second engagement portion 142 along its inclination, so that the first engagement portion 116 passes the second engagement portion 142 and reaches a position closer to the proximal end than the second engagement portion 142, as shown in FIG. 5(B). As a result, the distal end surface 116B of the first engagement portion 116 of the operating knob 110 is positioned on the proximal end side of the second engagement portion 142 of the locking portion 140.

[0087] Next, the surgeon stops the operation of moving the knob body 111 toward the base end. As a result, the operating knob 110 moves toward the tip end due to the reaction force received from the expansion body 21 and / or the biasing unit 120, and the tip surface 116B of the first engagement portion 116 of the operating knob 110 engages with the second engagement portion 142 of the locking unit 140 and stops. At this time, the operating knob 110 is located in the second position.

[0088] When the knob body 111 is displaced from the first position to the second position by the above-described operation, the displacement shaft 33 is displaced from the initial position shown in FIGS. 3 and 4 to the compressed position shown in FIG. 5(B), and the operating portion 114 provided on the operation knob 110 presses the distal end of the biasing portion 120 toward the proximal end. As a result, the proximal end of the biasing portion 120 presses the fixing member 170 toward the proximal end, and the displacement shaft 33 fixed to the fixing member 170 moves toward the proximal end. As a result, as shown in FIG. 11, the recess 55 of the expandable body 21 clamps the biological tissue. At this time, the biological tissue surrounding the through-hole Hh is clamped and well-held between the energy transmission portion 22 and the opposing portion 82. The operation knob 110 applies a traction force to the displacement shaft 33 via the biasing portion 120. Therefore, the biasing portion 120 can prevent a traction force exceeding the supportable force from acting on the displacement shaft 33. That is, when the force with which the expandable body 21 pinches the biological tissue becomes excessive, the biasing portion 120 contracts, and the compressive force that compresses the expandable body 21 in the axial direction is automatically adjusted. As a result, the force with which the biological tissue is pinched is automatically adjusted.

[0089] Next, in step S6, the surgeon performs a maintenance procedure to maintain the size of the through-hole Hh. In the maintenance procedure, the surgeon operates the power supply device 190 to apply high-frequency energy to the edge of the through-hole Hh via the electrode 24, thereby cauterizing (heating and cauterizing) the edge of the through-hole Hh with the high-frequency energy. The surgeon recognizes from information obtained from the notification unit 192 that the power output unit 191 has entered the output mode and is now able to output power, and causes the power output unit 191 to output power using an interface such as a keyboard, mouse, or dedicated button connected to the control unit 193.

[0090] When the biological tissue near the edge of the through-hole Hh is cauterized through the electrode 24, a denatured portion is formed near the edge where the biological tissue is denatured. Because the biological tissue in the denatured portion loses its elasticity, the through-hole Hh can maintain the shape it had when expanded by the expandable body 21. The through-hole Hh is held at an appropriate size by the expandable body 21, which has a buffer portion, and is cauterized, so it maintains its appropriate size and shape. This allows the through-hole Hh to be used as a shunt.

[0091] When the operation knob 110 is in the second position, as shown in FIG. 5(C), the first engagement portion 116 of the operation knob 110 is pressed against the second engagement portion 142 of the locking portion 140 by the reaction force of the expansion body 21 and / or the biasing portion 120. Therefore, the frictional force between the first engagement portion 116 and the second engagement portion 142 restricts the second engagement portion 142 of the locking portion 140 from displacing from the engagement position where it is engaged with the first engagement portion 116 to the release position. Therefore, even if there is an erroneous operation or malfunction, such as accidentally pressing the release button 141, while the operation knob 110 is in the second position before or during the maintenance procedure, the flexible deformation portion 143 bends and deforms to absorb the displacement, and the second engagement portion 142 engaged with the first engagement portion 116 is prevented from displacing from the engagement position to the release position.

[0092] After completing step S6, the surgeon reduces the diameter of the expandable body 21. To do this, first, as shown in FIG. 6(A), the surgeon operates the operation knob 110, which is located at the second position, to displace it to the third position, which is closer to the proximal end than the second position. As a result, the first engagement portion 116 of the operation knob 110 separates from the second engagement portion 142 of the locking portion 140, eliminating the frictional force and allowing the second engagement portion 142 to be displaced from the engagement position where it is engaged with the first engagement portion 116 to the release position. Next, the surgeon presses the release button 141 while maintaining the operation knob 110 at the third position. This rotates the locking portion 140, and the second engagement portion 142 is displaced from the engagement position to the release position. In this state, the surgeon operates the knob body 111 to displace the operation knob 110 to the first position, which is closer to the distal end, as shown in FIG. 6(B). At this time, because the second engagement portion 142 is located in the release position, the first engagement portion 116 can move past the second engagement portion 142 and toward the distal end of the second engagement portion 142. After the first engagement portion 116 moves past the second engagement portion 142 toward the distal end, the surgeon can release the release button 141. Then, when the surgeon moves the knob body 111 further toward the distal end with respect to the housing 100, the inclined surface 117C of the third engagement portion 117 comes into contact with the second engagement portion 142 of the locking portion 140. The inclined surface 117C can push and move the second engagement portion 142 along its inclination, so the third engagement portion 117 moves past the second engagement portion 142 and reaches a position distal to the second engagement portion 142. As a result, the base end surface 117B of the third engagement portion 117 of the operating knob 110 is positioned toward the distal end of the second engagement portion 142 of the locking portion 140. Therefore, the operation knob 110 can be displaced from the second position to the first position without being prevented from moving by the locking portion 140.

[0093] When the operation knob 110 is displaced to the first position, the compressive force acting on the expandable body 21 is released, and the expandable body 21 is now in a state where it can be contracted in diameter. Next, the surgeon stores the expandable body 21 in the outer tube 30 and removes it from the through-hole Hh. Furthermore, the surgeon removes the entire medical device 10 from the living body, completing the procedure.

[0094] As described above, the medical device 10 according to this embodiment includes the expansion body 21 having a central axis and capable of expanding and contracting in the radial direction, the long shaft portion 31 connected to the expansion body 21, the energy transmission portion 22 provided along the expansion body 21, the housing 100 connected to the base end of the shaft portion 31, the long displacement shaft 33 that compresses the expansion body 21 in the axial direction, the operation knob 110 for operating the displacement shaft 33 that is arranged so as to be movable from a first position via a second position to a third position approximately along the axis of the displacement shaft 33 relative to the housing 100, and the operation knob 110. and a locking portion 140 that locks the extension body 21 at a second position. The extension body 21 has a recess 55 recessed radially inward midway in the axial direction, a first connecting portion 54 connected to the shaft portion 31, and a second connecting portion 53 that is arranged to face the first connecting portion 54 across the recess 55 in the axial direction and is connected to the displacement shaft 33. The recess 55 has a distal upright portion 72, a proximal upright portion 73, and a bottom portion 71 located radially innermost and arranged between the distal upright portion 72 and the proximal upright portion 73, so as to define a receiving space 74 that can receive biological tissue. The energy transmission unit 22 is disposed along either the distal upright portion 72 or the proximal upright portion 73 so as to face the receiving space 74, the displacement shaft 33 extends from within the housing 100 along the shaft portion 31 and is connected to the second connecting portion 53, and is configured to compress the expansion body 21 in the axial direction by moving from an initial position to a compressed position relative to the shaft portion 31 along the axial direction of the expansion body 21 as the operation knob 110 moves from the first position to the second position, and the distal upright portion 72 and the proximal upright portion 73 form a displacement shaft The operating knob 110 is configured to grasp biological tissue by displacement of the operating knob 110 from an initial position to a compression position, and the operating knob 110 has a knob body 111 that protrudes from the housing 100 and is used to move the operating knob 110 from a first position to a third position, an action part 114 that is movably arranged within the housing 100 and is connected to the base end of the displacement shaft 33 and displaces the displacement shaft 33 from the initial position to the compression position as the operating knob 110 is moved, and a first engagement part 116 that displaces together with the action part 114, and the locking part 140 is arranged within the housing 100,The operation knob 110 has a second engagement portion 142 that is displaceable between an engagement position where it engages with the first engagement portion 116 of the operation knob 110 that is positioned at the second position and a release position where it is disengaged from the first engagement portion 116, a release button 141 that is exposed from the housing 100 and that displaces the second engagement portion 142 from the engagement position to the release position, and a flexible deformation portion 143 that connects the release button 141 and the second engagement portion 142, such that when the release button 141 is pressed with the operation knob 110 positioned at the second position, the flexible deformation portion 143 is deformed to prevent the second engagement portion 142 that is engaged with the first engagement portion 116 from displacing from the engagement position to the release position, and when the release button 141 is pressed with the operation knob 110 positioned at the third position, the second engagement portion 142 is displaced from the engagement position to the release position, thereby disengaging the first engagement portion 116 from the second engagement portion 142.

[0095] In the medical device 10 configured as described above, unless the operation knob 110 is moved from the second position to the third position, pressing the release button 141 prevents the second engagement portion 142 from moving from the engagement position to the release position, and therefore the locking portion 140 that locks the operation knob 110 at the second position, from being released. Therefore, with the expandable body 21 compressed to grasp the biological tissue, the medical device 10 can prevent the energy transmission portion 22 from being released from its pressed state against the biological tissue due to an erroneous operation or malfunction of the operation portion 23 before or during the output of energy from the energy transmission portion 22. This reduces the risk of thrombus formation due to exposure of the energy transmission portion 22 to blood, and of the energy transmission portion 22 damaging an unintended site.

[0096] The flexible deformation portion 143 has an elongated shape when projected onto a plane including the axis of the displacement shaft 33, and is rotatably disposed within the housing 100 so that the amount of inclination of the flexible deformation portion 143 with respect to the axis of the displacement shaft 33 can be changed, and the release button 141 and the second engagement portion 142 are disposed on both ends of the flexible deformation portion 143 in the direction along the axis of the displacement shaft 33, and pressing the release button 141 increases the inclination of the flexible deformation portion 143 with respect to the axis of the displacement shaft 33, displacing the second engagement portion 142 from the engagement position to the release position. As a result, the inclination of the flexible deformation portion 143 with respect to the housing 100 caused by pressing the release button 141 can displace the second engagement portion 142 from the engagement position to the release position. Furthermore, by bending the flexible deformation portion 143 and absorbing the displacement caused by the release button 141 with the flexible deformation portion 143, it is possible to prevent the second engagement portion 142 from being displaced from the engagement position to the release position even when the release button 141 is pressed.

[0097] The flexible deformation portion 143 has a rotation shaft portion 144 that protrudes in a direction approximately perpendicular to the axis of the displacement shaft 33, midway along the axis of the displacement shaft 33, and the housing 100 has a bearing portion 104 that receives the rotation shaft portion 144. As a result, by rotating the flexible deformation portion 143 around the rotation shaft portion 144 received in the bearing portion 104, the action of pressing the release button 141 can be converted into the action of displacing the second engagement portion 142 from the engagement position to the release position.

[0098] The medical device 10 has a biasing portion 120 that is elastically deformable along the axis of the displacement shaft 33 so as to bias the first engagement portion 116 of the operation knob 110, which is located in the second position, toward the second engagement portion 142. As a result, the second engagement portion 142 is pressed against the first engagement portion 116 by the biasing force of the biasing portion 120, and therefore, the second engagement portion 142 can be prevented from displacing from the engagement position to the release position by frictional force.

[0099] The action portion 114 of the operation knob 110 is connected to the base end of the displacement shaft 33 via the biasing portion 120. This allows the force with which the expandable body 21 grips the biological tissue to be appropriately adjusted by the biasing portion 120, thereby preventing the gripping force from becoming excessive and suppressing damage to the biological tissue.

[0100] The operation knob 110 has a third engagement portion 117 that engages with the second engagement portion 142 when the operation knob 110 is in the first position to prevent the operation knob 110 from moving from the first position to the second position, and the engagement between the second engagement portion 142 and the third engagement portion 117 can be released by pressing a release button 141. This prevents the operation knob 110 from unintentionally moving from the first position to the second position. This prevents the displacement shaft 33 from unintentionally moving toward the base end, which would hinder the contraction of the expandable body 21, which is capable of contracting in diameter, thereby improving safety.

[0101] The first connecting portion 54 of the expansion body 21 is located closer to the base end than the second connecting portion 53, and the displacement shaft 33 is configured to compress the expansion body 21 in the axial direction by pulling the second connecting portion 53 in the base end direction as it moves from the initial position to a compressed position located closer to the base end than the initial position; the operating knob 110 moves the displacement shaft 33 from the initial position to the compressed position as it moves from the first position to a second position located closer to the base end than the first position; the first engaging portion 116 is a first convex portion 116A that protrudes from the acting portion 114 in a direction approximately perpendicular to the axis of the displacement shaft 33 and includes a tip surface; and the second engaging portion 142 is a second convex portion that protrudes from the flexible deformation portion 143 in a direction approximately perpendicular to the axis of the displacement shaft 33 so as to engage with the tip surface of the first convex portion 116A. This allows the second protrusion provided on the locking portion 140 to engage with the tip surface of the first protrusion 116A provided on the operating knob 110, which has moved from the first position to the second position to compress the expansion body 21, thereby effectively maintaining the expansion body 21 in a compressed state.

[0102] The first convex portion 116A has an inclined surface 116C that is inclined so that the amount of protrusion from the operating portion 114 gradually decreases toward the base end of the first convex portion 116A, the tip surface 116A of the first convex portion 116A is a surface that is approximately perpendicular to the axis of the displacement shaft 33, and the second engagement portion 142 has a base end surface that is approximately perpendicular to the axis of the displacement shaft 33 and engages with the tip surface 116A of the first convex portion 116A. As a result, when the operation knob 110 moves from the first position to the second position, the inclined surface 117A of the first convex portion 116A comes into contact with the second engagement portion 142 and can smoothly ride over the second engagement portion 142, and when the operation knob 110 reaches the second position, the tip surface 116B of the first convex portion 116A engages with the second engagement portion 142, preventing the operation knob 110 from returning to the first position.

[0103] The present invention is not limited to the above-described embodiment, and various modifications may be made by those skilled in the art within the technical spirit of the present invention. For example, as shown in FIG. 13, the operation knob 110 may have a hook portion 118 that can engage with the second engagement portion 142. The hook portion 118 is a convex portion that protrudes from the top of the first engagement portion 116 in the protruding direction toward the tip side of the second engagement portion 142. The hook portion 118 protrudes along the axis of the operation knob 110. As shown in FIG. 13(A), when the operation knob 110 is located at the second position, the hook portion 118 hooks onto the second engagement portion 142 to prevent the second engagement portion 142 from moving from the engaged position to the released position. Then, as shown in FIG. 13(B), when the operation knob 110 is located at the third position, the hook portion 118 can be separated from the second engagement portion 142. This makes it possible to reliably prevent the second engagement portion 142 from being displaced from the engagement position to the release position by the hook portion 118 when the operation knob 110 is located at the second position.

[0104] The hook portion 118 is a convex portion that protrudes from the first engagement portion 116 toward the second engagement portion 142, so that it can firmly engage with the second engagement portion 142, and can easily be detached from the second engagement portion 142 to release the engagement when the operating knob 110 is moved to the third position.

[0105] 14 , the second connecting portion 53 and the first connecting portion 54 of the expandable body 21 may have separate structures. A distal upright portion 72 and a bottom portion 71 are disposed in the second connecting portion 53, and a proximal upright portion 73 is disposed in the first connecting portion 54. The distal upright portion 72, the bottom portion 71, and the proximal upright portion 73 define a receiving space 74 of the recess 55. The bottom portion 71 may be disposed in the first connecting portion 54. The energy transmission unit 22 is disposed in the first connecting portion 54, but may also be disposed in the second connecting portion 53. The first connecting portion 54 and the second connecting portion 53 are housed in the outer tube 30 in an elastically deformed and contracted state, and when exposed from the outer tube 30, they expand by their own elastic expansion force (restoring force). The shaft portion 31 is fixed to the base end of the first connecting portion 54, and the displacement shaft 33 is fixed to the base end of the second connecting portion 53. The displacement shaft 33 is slidable inside the shaft portion 31. Therefore, the displacement mechanism that axially compresses the expandable body 21 is a mechanism that pulls the displacement shaft 33 toward the base end or pushes the shaft portion 31 toward the distal end. By operating the displacement mechanism, as shown in FIG. 14(B), the distal upright portion 72 and the proximal upright portion 73 approach each other, reducing the receiving space 74, and the atrial septum HA, which is biological tissue, can be grasped between the distal upright portion 72 and the proximal upright portion 73.

[0106] The operation knob 110 and the displacement shaft 33 may be directly connected without a biasing portion. Alternatively, a biasing portion may be disposed between the base end of the action portion 114 of the operation knob 110 and the housing 100. [Explanation of symbols]

[0107] 10 Medical Devices 21 Extension 22 Energy transmission section 27 Connection terminal 31 Shaft section 33 Displacement shaft 53 2nd connection part 54 1st connection part 55 recess 71 Bottom 72 Tip side upright part 73 Proximal upright part 74 Receptive Space 100 cabinets 102 Knob opening 103 Button opening 104 Bearing section 110 Control knob 111 Knob body 114 Acting part 116 First engagement part 117 Third engagement part 118 Hook part 120 energizing section 140 Locking section 141 Cancel button 142 second engagement portion 143 Flexible deformation part 144 Rotating shaft

Claims

1. the device comprises an expansion body having a central axis and capable of expanding and contracting in a radial direction, a long shaft portion connected to the expansion body, an energy transmission portion provided along the expansion body, a housing connected to the base end of the shaft portion, a long displacement shaft that compresses the expansion body in the axial direction of the expansion body, an operation knob for operating the displacement shaft that is arranged to be movable along the axis of the displacement shaft relative to the housing from a first position via a second position to a third position, and a locking portion that locks the operation knob at the second position; The expansion body has a recess recessed radially inward midway in the axial direction, a first connecting portion connected to the shaft portion, and a second connecting portion arranged to face the first connecting portion across the recess in the axial direction and connected to the displacement shaft, The recess has a distal upright portion, a proximal upright portion, and a bottom portion located radially innermost between the distal upright portion and the proximal upright portion so as to define a receiving space capable of receiving biological tissue, the energy transmission portion is disposed along one of the distal upright portion and the proximal upright portion so as to face the receiving space, the displacement shaft extends from within the housing along the shaft portion and is connected to the second connecting portion, and is configured to compress the expansion body in the axial direction by moving from an initial position to a compressed position relative to the shaft portion along the axial direction of the expansion body as the operation knob moves from the first position to the second position, the distal end side standing portion and the proximal end side standing portion are configured to grasp the biological tissue by displacement of the displacement shaft from the initial position to the compression position, the operation knob includes a knob body that protrudes from the housing and is used to move the operation knob from the first position to the third position; an action portion that is movably disposed within the housing and is connected to a base end of the displacement shaft and displaces the displacement shaft from the initial position to the compressed position in response to the operation of moving the operation knob; and a first engagement portion that moves together with the action portion, the locking portion is disposed within the housing and includes a second engaging portion displaceable between an engaging position where the second engaging portion engages with the first engaging portion of the operation knob located at the second position and a releasing position where the engagement with the first engaging portion is released; a release button exposed from the housing for displacing the second engaging portion from the engaging position to the releasing position; and a flexible deformation portion connecting the release button and the second engaging portion; A medical device in which, when the release button is pressed while the operating knob is positioned at the second position, the flexible deformation portion deforms, preventing the second engagement portion engaged with the first engagement portion from displacing from the engagement position to the release position, and when the release button is pressed while the operating knob is positioned at the third position, the second engagement portion displaces from the engagement position to the release position, enabling the engagement between the first engagement portion and the second engagement portion to be released.

2. the flexible deformation portion has an elongated shape when projected onto a plane including the axis of the displacement shaft, and is rotatably disposed within the housing so that an amount of inclination of the flexible deformation portion with respect to the axis of the displacement shaft can be changed; the release button and the second engagement portion are disposed on both ends of the flexible deformation portion in a direction along the axis of the displacement shaft, The medical device according to claim 1 , wherein pressing the release button increases the inclination of the flexible deformation portion relative to the axis of the displacement shaft, thereby displacing the second engagement portion from the engagement position to the release position.

3. the flexible deformation portion has a rotation shaft portion that protrudes in a direction perpendicular to the axis of the displacement shaft, midway along the axis of the displacement shaft, The medical device according to claim 1 or 2, wherein the housing has a bearing portion that receives the pivot shaft portion.

4. A medical device according to any one of claims 1 to 3, having a biasing portion that is elastically deformable along the axis of the displacement shaft so as to bias the first engagement portion of the operating knob located in the second position toward the second engagement portion.

5. The medical device according to claim 4 , wherein the action portion of the operation knob is connected to the base end of the displacement shaft via the biasing portion.

6. the operation knob has a hook portion that can be engaged with the second engagement portion, A medical device according to any one of claims 1 to 5, wherein the hook portion is configured to hook onto the second engagement portion to prevent the second engagement portion from displacing from the engagement position to the release position when the operating knob is positioned at the second position, and to move away from the second engagement portion when the operating knob is positioned at the third position.

7. The medical device according to claim 6 , wherein the hook portion is a convex portion that protrudes from the first engaging portion toward the second engaging portion.

8. A medical device as described in any one of claims 1 to 7, wherein the operating knob has a third engagement portion that engages with the second engagement portion when the operating knob is in the first position to prevent the operating knob from moving from the first position to the second position, and the engagement between the second engagement portion and the third engagement portion can be released by pressing the release button.

9. the first connecting portion of the expansion body is located closer to the proximal end than the second connecting portion, the displacement shaft is configured to compress the expansion body in the axial direction by pulling the second connecting portion in a proximal direction as the displacement shaft moves from the initial position to the compressed position located on the proximal side of the initial position, the operation knob moves the displacement shaft from the initial position to the compressed position as the operation knob moves from the first position to the second position located on the proximal side of the first position, the first engagement portion is a first convex portion that protrudes from the action portion in a direction perpendicular to the axis of the displacement shaft and includes a tip end surface, A medical device described in any one of claims 1 to 8, wherein the second engagement portion is a second convex portion protruding from the flexible deformation portion in a direction perpendicular to the axis of the displacement shaft so as to engage with the tip surface of the first convex portion.

10. the first protrusion has an inclined surface that is inclined so that the amount of protrusion from the action portion gradually decreases toward the base end of the first protrusion, the tip surface of the first convex portion is a surface perpendicular to the axis of the displacement shaft, The medical device according to claim 9 , wherein the second engagement portion has a base end surface perpendicular to the axis of the displacement shaft that engages with the distal end surface of the first protrusion.

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