Torque transmission mechanism, assembly method, and conveying device for implantable medical device

Abstract

Provided in the present invention are a torque transmission mechanism, an assembly method, and a conveying device for an implantable medical device. The torque transmission mechanism comprises a torque transmitting member, a torque receiving member and a limiting member, wherein the torque transmitting member is sleeved at the periphery of the torque receiving member in the axis direction of the torque receiving member, and is configured to receive the torque from an inner sheath tube and transmit the torque to the torque receiving member; when the torque transmitted by the torque transmitting member is not greater than a rated value, the torque received by the torque receiving member is equal to the torque transmitted by the torque transmitting member, and the torque transmitting member drives the torque receiving member to rotate synchronously; when the torque transmitted by the torque transmitting member is greater than the rated value, the torque transmitting member rotates around the torque receiving member, such that the torque received by the torque receiving member is not greater than the rated value; and the limiting member is used for limiting a position of the torque transmitting member in the axis direction of the torque receiving member relative to the torque receiving member. Such a configuration can ensure that the torque transmitting member can only transmit to the torque receiving member a torque which is not greater than the rated value.

Description

Torque transmission mechanism, assembly method, and delivery device for implantable medical device Technical Field

[0001] The present invention relates to the technical field of medical devices, and in particular to a torque transmission mechanism, an assembly method, and a delivery device for an implantable medical device. Background Art

[0002] Currently, there are two main methods for leadless pacemaker implantation and fixation: active helical fixation and hook-type fixation. During active helical fixation, to prevent the risk of perforation caused by excessive rotation of the distal helical portion of the leadless pacemaker into the heart, a torque-limiting structure is typically added to the leadless pacemaker or delivery device to ensure that the torque delivered by the delivery device to the leadless pacemaker is less than the torque required to rotate the distal helical portion into the heart and perforate the heart.

[0003] During implantation, a dedicated delivery device is required to deliver the leadless pacemaker into the patient's ventricles and implant it within the interventricular septum, achieving physiological pacing. The implantation process involves the physician installing the leadless pacemaker and torque-limiting mechanism in the operating room. The physician then uses the torque catheter in the control handle to retract the leadless pacemaker into the housing. The delivery device is then inserted into the established channel of the guide sheath. Once the housing containing the leadless pacemaker enters the right atrium, the sheath is bent to allow the housing to pass through the tricuspid valve and enter the right ventricle. Contrast agent is injected to confirm that the distal end of the housing is perpendicular to the mid- and low-ventricular septum. The torque catheter is then pushed forward to drive the docking cap forward, exposing the distal helical portion of the leadless pacemaker from the housing. The torque catheter is then rotated to insert the distal helical portion into the interventricular septum. Continued manipulation of the torque catheter disengages the torque-limiting mechanism.

[0004] Before performing an electrical signal test, the housing is withdrawn from the ventricle to the atrium, leaving only the safety wire connected to the leadless pacemaker. After testing and confirming that the signal and function of the leadless pacemaker meet the requirements, the safety wire is separated from the leadless pacemaker, and the delivery device and introducer sheath are removed. If the test confirms that the signal or function does not meet the requirements, the housing can be further advanced from the atrium to the ventricle, and the implantation process can be repeated.

[0005] The following risks or defects in the above-mentioned leadless pacemaker implantation process may easily lead to surgical failure:

[0006] First, the doctor needs to install the torque limiting structure on site during the operation, which increases the operation time.

[0007] Secondly, after the leadless pacemaker is screwed into the ventricular septum, if the torque limiting structure does not separate as designed, the following problems may occur:

[0008] a. Misoperation (e.g., withdrawal) of the torque catheter may cause the torque limiting structure to pull the leadless pacemaker directly out of the ventricular septum, resulting in severe damage to the ventricular septum.

[0009] b. Incorrect rotation of the torque catheter may cause the distal spiral portion of the leadless pacemaker to rotate out of the myocardial tissue. Although this incorrect operation itself will not cause damage to the ventricular septum, it requires the removal of the leadless pacemaker and delivery device, replacement of the delivery device and leadless pacemaker, and re-implantation. These operations increase the operation time and risk.

[0010] Thirdly, after the torque limiting structure is separated, during the process of being stored into the shell, the torque limiting structure is prone to scratching myocardial tissues such as trabeculae, ventricular septum, ventricular side wall or tricuspid valve chordae tendineae.

[0011] Summary of the Invention

[0012] The object of the present invention is to provide a torque transmission mechanism, an assembly method and a delivery device for an implantable medical device, so as to solve one or more problems existing in the delivery device of the existing implantable medical device during the implantation process.

[0013] To solve the above technical problems, the present invention provides a torque transmission mechanism, which is used to drive an implantable medical device to rotate and implant it at a target position; the torque transmission mechanism includes: a torque transmission member, a torque receiving member, and a limit member;

[0014] The torque transmission member is sleeved on the outer circumference of the torque receiving member along the axial direction of the torque receiving member, and the torque transmission member is used to receive torque from the inner sheath and transmit torque to the torque receiving member; when the torque of the torque transmission member is not greater than the rated value, the torque of the torque receiving member is equal to the torque of the torque transmission member, and the torque transmission member drives the torque receiving member to rotate synchronously; when the torque of the torque transmission member is greater than the rated value, the torque transmission member rotates around the torque receiving member so that the torque of the torque receiving member is not greater than the rated value; the limit member is used to limit the position of the torque transmission member relative to the torque receiving member along the axial direction of the torque receiving member.

[0015] Optionally, the torque transmission mechanism further comprises a docking member and a connecting member, wherein the docking member is provided at the distal end of the torque receiving member along the axial direction of the torque receiving member; and the connecting member is provided at the proximal end of the torque transmitting member along the axial direction of the torque transmitting member.

[0016] The limiting member is connected to the docking member and the connecting member respectively; wherein the docking member and / or the connecting member are rotatably connected around the limiting member, and the docking member limits the position of the limiting member along the axial direction of the torque receiving member, and the connecting member limits the position of the limiting member along the axial direction of the torque transmitting member.

[0017] Optionally, one of the connecting member and the limiting member has a circumferentially arranged first limiting groove, and the other has a circumferentially arranged first protrusion, the first protrusion being engaged with the first limiting groove to limit the relative positions of the connecting member and the limiting member along the axial direction of the torque transmission member; and / or;

[0018] One of the docking member and the limiting member has a circumferentially arranged second limiting groove, and the other has a circumferentially arranged second protrusion, which is engaged with the second limiting groove to limit the relative positions of the docking member and the limiting member along the axial direction of the torque receiving member.

[0019] Optionally, the docking member is fixedly connected, snap-connected or threadedly connected to the limiting member; the connecting member has a first circumferentially arranged limiting groove, and the limiting member has a circumferentially arranged first protrusion, and the first protrusion is snapped into the first limiting groove so that the limiting member is rotatably connected to the connecting member around the connecting member.

[0020] Optionally, the limiting member includes a cylindrical section, which surrounds the torque transmission member and shields the torque transmission member in the axial direction of the torque transmission member.

[0021] Optionally, the docking member includes a support portion extending along its own radial direction, and the distal end of the cylindrical section is connected to the support portion; the support portion has a first through hole and / or the cylindrical section has a second through hole; the limiting member includes a necking section arranged at the proximal end of the cylindrical section, the necking section narrows in a direction away from the support portion, and the necking section has a third through hole; the first through hole and / or the second through hole is connected to the third through hole through the first inner cavity of the cylindrical section.

[0022] Optionally, the torque transmission mechanism also includes a docking piece arranged at the distal end of the torque receiving piece, the docking piece having a second inner cavity for docking with the implantable medical device, the distal end of the second inner cavity being open, allowing the implantable medical device to move in and out along the axial direction of the docking piece; when the proximal end of the implantable medical device is accommodated in the second inner cavity, the second inner cavity is also used to limit the circumferential rotation of the implantable medical device.

[0023] Optionally, the cross-section of the second inner cavity has a first reference axis and a second reference axis passing through the center of the cross-section, and the first reference axis and the second reference axis are perpendicular; wherein the cross-section is symmetrical about the first reference axis, the cross-section is symmetrical about the second reference axis, and the size of the cross-section in the direction of the first reference axis is different from the size of the cross-section in the direction of the first reference axis.

[0024] Optionally, the torque transmission mechanism also includes a docking piece arranged at the distal end of the torque receiving piece, the docking piece having a plurality of grooves for docking with the implantable medical device, and the plurality of grooves are circumferentially arranged around the axis of the docking piece; the grooves are used for the implantable medical device to be inserted along the axial direction of the docking piece to limit the circumferential rotation of the implantable medical device.

[0025] Optionally, the torque transmission member and the torque receiving member are interference fit, and when the torque of the torque transmission member is not greater than the rated value, the torque transmission member and the torque receiving member are relatively fixed; when the torque of the torque transmission member is greater than the rated value, the torque transmission member overcomes the friction between itself and the torque receiving member and rotates around the torque receiving member.

[0026] Optionally, the torque transmitting member includes a torsion spring, the torque receiving member has a cylindrical outer peripheral wall, and the torsion spring is coiled on the outer peripheral wall.

[0027] Optionally, the torque transmitting member has a fourth through hole extending along its own axial direction, and the torque receiving member has a fifth through hole extending along its own axial direction, and the fourth through hole and the fifth through hole are used for passing a safety wire.

[0028] To solve the above technical problems, the present invention further provides a method for assembling a torque transmission mechanism, which is used to assemble the torque transmission mechanism described above. The method for assembling the torque transmission mechanism comprises:

[0029] Sleeve the torque transmission member on the torque receiving member;

[0030] performing a torque test on the torque transmitting member and the torque receiving member, applying a torque greater than the rated value to the torque transmitting member, and if the torque transmitting member rotates around the torque receiving member, the torque test is passed;

[0031] After passing the torque test, the limiting member is connected to the torque transmitting member and the torque receiving member respectively to limit the position of the torque transmitting member relative to the torque receiving member along the axial direction of the torque receiving member.

[0032] Optionally, the assembly method of the torque transmission mechanism further includes:

[0033] Before the torque transmission member is sleeved on the torque receiving member, a connecting member is assembled and connected to the proximal end of the torque transmission member;

[0034] After passing the torque test, the docking member provided at the distal end of the torque receiving member is fixedly connected to the limiting member, and then the first protrusion of the limiting member is installed into the first limiting groove of the connecting member, so that the limiting member and the connecting member are rotatably connected.

[0035] To solve the above technical problems, the present invention further provides a delivery device for an implantable medical device, which includes the torque transmission mechanism as described above, and also includes an outer sheath, an inner sheath, and a safety wire;

[0036] The inner sheath tube is movably provided in the outer sheath tube; the safety wire is movably provided in the inner sheath tube and the torque transmission mechanism; the inner sheath tube is connected to the torque transmission member of the torque transmission mechanism and is used to drive the torque receiving member of the torque transmission mechanism to move;

[0037] The distal end of the torque transmission mechanism is used to be detachably connected to the implantable medical device, and the torque receiving member of the torque transmission mechanism is used to limit the circumferential rotation of the implantable medical device when connected to the implantable medical device;

[0038] The safety wire is used to be detachably connected to the implantable medical device.

[0039] To sum up, in the torque transmission mechanism, assembly method and delivery device of implantable medical equipment provided by the present invention, the torque transmission mechanism includes: a torque transmission member, a torque receiving member and a limit member; the torque transmission member is sleeved on the outer periphery of the torque receiving member along the axial direction of the torque receiving member, and the torque transmission member is used to receive torque from the inner sheath and transmit torque to the torque receiving member; when the torque of the torque transmission member is not greater than the rated value, the torque of the torque receiving member is equal to the torque of the torque transmission member, and the torque transmission member drives the torque receiving member to rotate synchronously; when the torque of the torque transmission member is greater than the rated value, the torque transmission member rotates around the torque receiving member so that the torque of the torque receiving member is not greater than the rated value; the limit member is used to limit the position of the torque transmission member relative to the torque receiving member along the axial direction of the torque receiving member.

[0040] With this configuration, based on the arrangement of the torque transmitter and the torque receiver, when the torque of the torque transmitter exceeds the rated value, it will rotate and slip around the torque receiver, thereby ensuring that the torque transmitter can only transmit torque that does not exceed the rated value to the torque receiver. Furthermore, the torque transmitter and torque receiver do not need to be separated, eliminating gaps caused by separation failure. The provision of a stopper ensures that the torque transmitter and torque receiver will not separate along the axis, ensuring the reliability of the entire torque transmission mechanism and eliminating the risk of myocardial tissue being scratched after the torque transmitter and torque receiver separate. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] Those skilled in the art will appreciate that the accompanying drawings are provided for a better understanding of the present invention and do not constitute any limitation on the scope of the present invention.

[0042] FIG1 is a schematic diagram of an application scenario of a delivery device and an implantable medical device according to an embodiment of the present invention, wherein the implantable medical device is separated from a docking member, and a safety wire is connected to the implantable medical device.

[0043] 2 is a schematic diagram of an application scenario of a delivery device and an implantable medical device according to an embodiment of the present invention, wherein the implantable medical device is connected to a docking piece, and a safety wire is connected to the implantable medical device.

[0044] FIG3 is a schematic cross-sectional view of the implantable medical device according to an embodiment of the present invention when housed in a housing in the axial direction.

[0045] FIG. 4 is a schematic diagram of a torque transmission mechanism according to an embodiment of the present invention.

[0046] FIG5 is a schematic cross-sectional view of the torque transmission mechanism according to the embodiment of the present invention in the axial direction.

[0047] 6a to 6c are schematic diagrams of the distal end side of three preferred examples of the torque transmission mechanism according to the embodiment of the present invention.

[0048] FIG7 is a schematic cross-sectional view of an axial direction of a torque transmission mechanism according to another preferred embodiment of the present invention, wherein the docking member and the limiting member are connected by snap-fit ​​connection.

[0049] FIG8 is a schematic cross-sectional view in the axial direction of another preferred example of a torque transmission mechanism according to an embodiment of the present invention, wherein the docking member and the limiting member are connected by threads.

[0050] FIG9 is a schematic cross-sectional view in the axial direction of a torque transmission mechanism according to another preferred example of an embodiment of the present invention.

[0051] FIG. 10 is a schematic diagram of a torque transmission mechanism according to another preferred example of an embodiment of the present invention.

[0052] In the accompanying drawings: 1-implantable medical device; 11-distal end portion; 12-proximal end portion; 2-torque transmission mechanism; 21-torque transmission member; 211-fourth through hole; 22-torque receiving member; 221-fifth through hole; 23-limiting member; 230-first inner cavity; 231-cylindrical section; 232-narrowed section; 233-third through hole; 24-docking member; 240-second inner cavity; 241-supporting portion; 242-first through hole; 243-guide slope; 244-groove; 25-connecting member; 250-main body; 251-limiting platform; 252-limiting block; 253-sixth through hole; 3-outer sheath; 4-inner sheath; 5-safety wire; 6-shell; 71-first limiting groove; 72-first protrusion. DETAILED DESCRIPTION

[0053] To make the objects, advantages, and features of the present invention more clearly apparent, the present invention is further described below in conjunction with the accompanying drawings and specific embodiments. It should be noted that the drawings are all in a very simplified form and are not drawn to scale. They are only used to conveniently and clearly assist in illustrating the purposes of the embodiments of the present invention. In addition, the structures shown in the drawings are often part of the actual structure. In particular, different drawings may need to illustrate different focuses and sometimes use different scales.

[0054] As used in the present invention, the singular forms "a", "an" and "the" include plural objects, the term "or" is generally used in a sense including "and / or", the term "several" is generally used in a sense including "at least one", and the term "at least two" is generally used in a sense including "two or more". In addition, the terms "first", "second" and "third" are used for descriptive purposes only and are not to be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first", "second" and "third" may explicitly or implicitly include one or at least two of the features, "one end" and "the other end" as well as "proximal end" and "distal end" generally refer to two corresponding parts, which include not only the endpoints. The terms "proximal end" and "distal end" are defined herein with respect to a delivery device for an implantable medical device, which has one end for inserting into the human body and a manipulation end extending outside the body. The term "proximal end" refers to the position of an element closer to the control end of the delivery device extending outside the body, and the term "distal end" refers to the position of an element closer to the end of the delivery device that is inserted into the human body and therefore further away from the control end of the delivery device. Optionally, in manual or hand-operated applications, the terms "proximal end" and "distal end" are defined herein relative to an operator, such as a surgeon or clinician. The term "proximal end" refers to the position of an element closer to the operator, and the term "distal end" refers to the position of an element closer to the delivery device of the implantable medical device and therefore further away from the operator. In addition, as used in the present invention, "mounted," "connected," "connected," and "disposed" of one element to another should be understood broadly and generally only indicate that there is a connection, coupling, mating, or transmission relationship between the two elements, and the connection, coupling, mating, or transmission relationship between the two elements can be direct or indirect through an intermediate element. It should not be understood to indicate or imply a spatial positional relationship between the two elements, that is, one element can be in any orientation, such as inside, outside, above, below, or to the side of another element, unless the content clearly indicates otherwise. For those skilled in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances. In addition, directional terms such as above, below, up, down, upward, downward, left, right, etc. are used with respect to the exemplary embodiments as they are shown in the figures, with the upward or upper direction being toward the top of the corresponding figure and the downward or lower direction being toward the bottom of the corresponding figure.

[0055] The present invention aims to provide a torque transmission mechanism, an assembly method, and a delivery device for an implantable medical device to solve the problems existing in the delivery devices for existing implantable medical devices during the implantation process.

[0056] Referring to Figures 1 to 3, an embodiment of the present invention provides a delivery device for an implantable medical device, which is used to deliver and implant an implantable medical device 1 (such as a leadless pacemaker) into a target location (such as the ventricular septum of the heart). The delivery device includes: a torque transmission mechanism 2, an outer sheath 3, an inner sheath 4, and a safety wire 5. The inner sheath 4 is movably inserted into the outer sheath 3; the safety wire 5 is movably inserted into the inner sheath 4 and the torque transmission mechanism 2; the inner sheath 4 is connected to the torque transmission member 21 of the torque transmission mechanism 2 and is used to drive the torque receiving member 22 of the torque transmission mechanism 2 to move; the distal end of the torque transmission mechanism 2 is used to be detachably connected to the implantable medical device 1, and when the torque receiving member 22 of the torque transmission mechanism 2 is connected to the implantable medical device 1, the circumferential rotation of the implantable medical device 1 is restricted; the safety wire 5 is used to be detachably connected to the implantable medical device 1 and is used to lock the implantable medical device 1 during delivery to prevent the implantable medical device 1 from falling off. After the implantable medical device 1 is implanted and passes the test, the safety thread 5 can be separated from the implantable medical device 1 .

[0057] The structure and principle of the delivery device of the implantable medical device are described below in conjunction with Figures 1 to 3. As shown in Figures 1 and 2, in an exemplary embodiment, the distal portion 11 of the implantable medical device 1 is spiral-shaped, which is used to screw into the target position to fix the entire implantable medical device 1 at the target position. The proximal portion 12 of the implantable medical device 1 is detachably connected to the safety wire 5, for example, by a threaded connection. It will be understood that when it is necessary to separate the implantable medical device 1 and the safety wire 5, the safety wire 5 can be separated from the proximal portion 12 of the implantable medical device 1 by rotating the safety wire 5.

[0058] When the proximal portion 12 of the implantable medical device 1 is in an assembled connection with the safety wire 5, the safety wire 5 moves forward and backward along its own axial direction (horizontally in FIG1 ) to drive the implantable medical device 1 to move forward and backward along its axial direction. FIG1 shows a state in which the implantable medical device 1 is separated from the docking member 24 of the torque transmission mechanism 2. Based on FIG1 , pulling the safety wire 5 toward the proximal end (the right side of FIG1 ) can pull the implantable medical device 1 to a position where it connects with the torque transmission mechanism 2, thereby forming a connection between the implantable medical device 1 and the torque transmission mechanism 2, thereby limiting the circumferential rotation of the implantable medical device 1 relative to the torque transmission mechanism 2, as shown in FIG2 .

[0059] As previously described, distal portion 11 of implantable medical device 1 is used to screw into a target location, securing the entire implantable medical device 1 there. However, since safety wire 5 is relatively thin and generally cannot transmit significant torque, a certain amount of torque must be transmitted through torque transmission mechanism 2 to drive the entire implantable medical device 1 to rotate about its axis and screw distal portion 11 into the target location. By pulling safety wire 5 toward the proximal end (the right side of FIG. 1 ), the implantable medical device 1 is connected to torque transmission mechanism 2, which then transmits torque to the implantable medical device 1.

[0060] Further, referring to FIG3 , the inner sheath 4 can be a braided tube, a multi-strand spring tube, a double-layer tube, or other tubing with a certain degree of torsion resistance. The torque transmission member 21 of the torque transmission mechanism 2 is connected to the inner sheath 4 (as shown in FIG5 ). When the inner sheath applies a torque no greater than the rated value to the torque transmission member, the inner sheath 4 can transmit the torque to the torque receiving member 22 through the torque transmission mechanism 2, and then to the implantable medical device 1. As a result, when the inner sheath 4 rotates about its axis, it can drive the implantable medical device 1 to rotate about its axis.

[0061] Optionally, as shown in FIG3 , the delivery device of the implantable medical device 1 further includes a shell 6, the proximal end of the shell 6 (i.e., the right end of the shell 6 in FIG3 ) is connected to the outer sheath 3, and the shell 6 has a cavity open toward the distal end, which is used to accommodate the implantable medical device 1 and the torque transmission mechanism 2. Referring to FIG2 and FIG3 , the inner sheath 4 can also move relative to the outer sheath 3 along the axial direction of the outer sheath 3, thereby moving along the axial direction of the outer sheath 3 together with the torque transmission mechanism 2, and with the safety wire 5, the implantable medical device 1 and the torque transmission mechanism 2 can be received together in the shell 6 to form a preparatory form before implantation. Preferably, the outer sheath 3 is a controllable bending sheath, and the shell 6 can be subsequently placed in the guide sheath to perform the pushing and implanting steps.

[0062] Please refer to Figures 4 and 5. In order to solve the problems existing in the existing delivery device during the implantation process, an embodiment of the present invention provides a specific implementation of a torque transmission mechanism 2, which is used to drive the implantable medical device 1 to rotate so that its distal end, such as the spiral distal end, is implanted at the target position. The torque transmission mechanism 2 includes: a torque transmission member 21, a torque receiving member 22 and a limit member 23; the torque transmission member 21 is sleeved on the outer periphery of the torque receiving member 22 along the axial direction of the torque receiving member 22, and the torque transmission member 21 is used to receive torque from the inner sheath 4 and transmit torque to the torque receiving member 22; when the torque of the torque transmission member 21 is not greater than the rated value, the torque of the torque receiving member 22 is equal to the torque of the torque transmission member 21, and the torque transmission member 21 drives the torque receiving member 22 to rotate synchronously; when the torque of the torque transmission member 21 is greater than the rated value, the torque transmission member 21 rotates around the torque receiving member 22 so that the torque of the torque receiving member 22 is not greater than the rated value; the limit member 23 is used to limit the position of the torque transmission member 21 relative to the torque receiving member 22 along the axial direction of the torque receiving member 22.

[0063] The rated value of torque herein refers to the value at which the maximum rotational friction torque between the torque transmission component 21 and the torque receiving component 22 is balanced, also defined as the maximum rated torque value, which is also the torque required for myocardial implantation.

[0064] In one application scenario of the delivery device, the torque transmission member 21 is mainly located at the proximal side, and is used to input torque, such as connecting to the inner sheath 4. The torque receiving member 22 is mainly located at the distal side, and is used to output torque, such as connecting to the implantable medical device 1.

[0065] It should be noted that the torque of the torque transmission member 21 refers to the torque generated by the torque transmission member 21 under the external torque drive, such as the rotational torque generated by the inner sheath 4 on the torque transmission member 21. When the inner sheath 4 is rotated, the torque on the torque transmission member 21 will produce a tendency to rotate. If the resistance torque of the external environment or external structure to the torque receiving member 22 is less than the maximum rated torque value on the torque transmission member 21, the torque transmission member 21 rotates around its own axis and simultaneously drives the torque receiving member 22 to rotate in the same direction, and the two are in a relatively static state. If the resistance torque of the external environment or external structure to the torque receiving member 22 is not less than the maximum rated torque value on the torque transmission member 21, the torque transmission member 21 cannot drive the torque receiving member 22 to rotate synchronously. At this time, the torque transmission member 21 rotates due to the torque from the rotating inner sheath 4, but the torque receiving member 22 remains stationary, that is, the torque transmission member 21 slips circumferentially on the torque receiving member 22, and the two are in a relative circular motion state. The external resistance torque mainly comes from the counter-torque generated during the process of the implantable medical device 1 being screwed into the myocardial tissue.

[0066] In another application scenario of the delivery device, for example, when the distal end 11 of the implantable medical device 1 has been screwed into the target position, the inner sheath 4 gradually increases the output torque, and the torque on the torque transmission member 21 gradually increases to exceed the rated value, the rotational friction torque balance between the torque transmission member 21 and the torque receiving member 22 is broken, and the torque transmission member 21 begins to slip and rotate relative to the torque receiving member 22, thereby preventing the torque on the torque receiving member 22 from exceeding the rated value, thereby avoiding the distal end 11 of the implantable medical device 1 from applying excessive torque to the target position and causing perforation of the cardiac tissue. The setting of the rated value can be selected by those skilled in the art according to actual conditions. The inventor has found through research and multiple experimental verifications that, under normal circumstances, the torque of the implantable medical device 1 of about 0.2N·cm can meet the implantation requirements, while the perforation torque required to cause perforation of cardiac tissue is greater than 1N·cm. To ensure safety, the rated value should be set to be greater than 0.2N·cm, less than the perforation torque, and leave a certain safety margin. Therefore, the rated value may be selected to be slightly larger than 0.2 N·cm, such as 0.5 N·cm or 0.6 N·cm. Of course, those skilled in the art may configure the rated value differently according to the age and physical condition of the patient.

[0067] With this configuration, based on the arrangement of the torque transmission member 21 and the torque receiving member 22, when the torque of the torque transmission member 21 exceeds the rated value, it will rotate and slip around the torque receiving member 22, thereby ensuring that the torque transmission member 21 can only transmit torque that does not exceed the rated value to the torque receiving member 22. Furthermore, the torque transmission member 21 and the torque receiving member 22 do not need to be separated, eliminating gaps caused by separation failure. The provision of the stopper 23 ensures that the torque transmission member 21 and the torque receiving member 22 will not separate along the axis of the torque receiving member 22, ensuring the reliability of the entire torque transmission mechanism 2 and eliminating the risk of myocardial tissue being scratched after the torque transmission member 21 and the torque receiving member 22 separate.

[0068] Preferably, the torque transmission member 21 and the torque receiving member 22 have an interference fit. When the torque of the torque transmission member 21 is not greater than the rated value, the torque transmission member 21 and the torque receiving member 22 are relatively fixed. When the torque of the torque transmission member 21 is greater than the rated value, the torque transmission member 21 overcomes the friction between the torque transmission member 21 and the torque receiving member 22 and rotates around the torque receiving member 22. It should be noted that the interference fit between the torque transmission member 21 and the torque receiving member 22 is only a preferred example of the connection between the two and does not limit the connection method between the two. In some embodiments, the torque transmission member 21 and the torque receiving member 22 may also adopt a self-restoring torque transmission connection method such as magnetic coupling connection, butt friction connection, or slipping tooth connection. At the same time, these torque transmission connection methods can also achieve the effect of limiting torque output when torque is overloaded, and the present invention is not limited to this.

[0069] In this embodiment, the torque transmission member 21 includes a torque spring, and the torque receiving member 22 has a cylindrical outer peripheral wall. The torque spring is coiled around the outer peripheral wall of the torque receiving member 22. In its unstressed initial state, the inner diameter of the torque spring is slightly smaller than the outer diameter of the outer peripheral wall of the torque receiving member 22. This creates an interference fit when the torque spring is coiled around the outer peripheral wall. Optionally, the torque spring is formed from a single wire wound with a specific pitch, direction, and length. The wire material may be 304 stainless steel or 316 stainless steel. Because the torque spring is coiled around the outer peripheral wall of the torque receiving member 22 with an interference fit, friction exists between the two. When the torque on the torque spring does not exceed the rated value, the torque can be transmitted to the torque receiving member 22 at a 1:1 ratio. When the torque on the torque spring exceeds the rated value, the torque spring overcomes the friction and causes circumferential slipping rotation relative to the outer peripheral wall of the torque receiving member 22. The torque receiving member 22 needs to transmit torque and therefore needs to have a certain torsional strength. Therefore, the material thereof is preferably made of metal, such as 304 stainless steel or 316 stainless steel.

[0070] Continuing to refer to FIG4 and FIG5 , in an alternative exemplary embodiment, the torque transmission mechanism 2 further includes a docking member 24 and a connecting member 25, wherein the docking member 24 is disposed at the distal end of the torque receiving member 22 along the axial direction of the torque receiving member 22; the connecting member 25 is disposed at the proximal end of the torque transmitting member 21 along the axial direction of the torque transmitting member 21; and the limiting member 23 is connected to the docking member 24 and the connecting member 25, respectively. The docking member 24 and / or the connecting member 25 are rotatably connected about the limiting member 23, and the docking member 24 limits the position of the limiting member 23 along the axial direction of the torque receiving member 22, while the connecting member 25 limits the position of the limiting member 23 along the axial direction of the torque transmitting member 21. Referring to FIG1 to FIG3 , the docking member 24 is primarily used to dock with the proximal portion 12 of the implantable medical device 1 and to transmit torque to the proximal portion 12. The connecting member 25 is used to connect with the inner sheath tube 4 to transmit the torque from the inner sheath tube 4 to the torque transmission member 21. Of course, in other embodiments, the docking member 24 and the torque receiving member 22 can also be integrally formed.

[0071] At least one of the docking member 24 and the connecting member 25 is rotatably connected to the stopper 23. Therefore, when the torque transmission member 21 and the torque receiving member 22 rotate, the stopper 23 does not hinder the relative rotation of the torque transmission member 21 and the torque receiving member 22. The docking member 24 and the connecting member 25 maintain the relative position of the torque transmission member 21 and the torque receiving member 22 along the axis of the torque receiving member 22 through the stopper 23. Even when the torque transmission member 21 and the torque receiving member 22 rotate, the torque transmission member 21 and the torque receiving member 22 will not slip or separate, eliminating the risk of myocardial tissue being scratched by the separation of the torque transmission member 21 and the torque receiving member 22. It should be noted that in some embodiments, only one of the docking member 24 and the connecting member 25 can be rotatably connected to the stopper 23, while the other can be fixedly connected to the stopper 23. In other embodiments, both the docking member 24 and the connecting member 25 can be rotatably connected to the limiting member 23 respectively, and both can achieve the effect of decoupling rotation.

[0072] Optionally, one of the connecting member 25 and the limiting member 23 has a circumferentially arranged first limiting groove 71, and the other has a circumferentially arranged first protrusion 72, and the first protrusion 72 is engaged in the first limiting groove 71 to limit the relative positions of the connecting member 25 and the limiting member 23 along the axial direction of the torque transmitting member 21; and / or; one of the docking member 24 and the limiting member 23 has a circumferentially arranged second limiting groove (not shown), and the other has a circumferentially arranged second protrusion (not shown), and the second protrusion is engaged in the second limiting groove to limit the relative positions of the docking member 24 and the limiting member 23 along the axial direction of the torque receiving member 22.

[0073] In this embodiment, as shown in FIG5 , the docking member 24 is fixedly connected to the limiting member 23, while the connecting member 25 is rotatably connected to the limiting member 23. Specifically, the connecting member 25 has a circumferentially arranged first limiting groove 71, and the limiting member 23 has a circumferentially arranged first protrusion 72. The first protrusion 72 engages with the first limiting groove 71, so that the limiting member 23 is rotatably connected to the connecting member 25 around the connecting member 25. Considering the convenience of assembly, the first limiting groove 71 can be formed by sequentially assembling the components of the connecting member 25. For example, the connecting member 25 includes a main body 250, a limit platform 251 radially protruding outward from the main body 250, and a detachable limit block 252. The first protrusion 72 of the limit member 23 can be annular or have several circumferentially distributed teeth. The first protrusion 72 can be rotatably mounted on the main body 250 from the proximal end to the distal end (from right to left in Figure 5), and then the limit block 252 is installed on the main body 250 from the proximal end to the distal end to a position close to or abutting against the first protrusion 72, and then the limit block 252 is fixed to the main body 250 and the inner sheath 4, such as by welding, melting or gluing, so that a first limit groove 71 is formed between the limit platform 251 and the limit block 252, and the first protrusion 72 is snapped into the first limit groove 71. Preferably, the first protrusion 72 is annular, with an inner diameter greater than the outer diameter of the body 250, i.e., the diameter of the connector 25 at the first limiting groove 71. This creates a clearance fit between the first protrusion 72 and the body 250 to prevent rotational resistance. It will be appreciated that the structure and connection relationship between the second limiting groove and the second protrusion can be referenced to the structure and connection relationship between the first limiting groove 71 and the first protrusion 72. This description will not be repeated here.

[0074] As shown in Figure 7, in another preferred embodiment, the connecting member 25 is rotatably connected to the retaining member 23, and the docking member 24 is fixedly connected to the retaining member 23 via a snap-fit ​​connection. The snap-fit ​​connection requires a certain degree of elasticity, so the retaining member 23 is preferably made of a polymer material such as PU (polyurethane), PEBAX (polyether block polyamide), PE (polyethylene), and other materials that meet biocompatibility requirements.

[0075] As shown in FIG8 , in another preferred embodiment, on the basis of the rotational connection between the connecting member 25 and the limiting member 23, the docking member 24 and the limiting member 23 are fixedly connected by a threaded connection. The docking member 24 and the limiting member 23 are made of the same metal material, such as 304 stainless steel, 316 stainless steel, titanium alloy, etc. The docking member 24 and the limiting member 23 are basically the same in terms of fatigue performance and other properties, and are easy to disassemble and replace. Based on the connection methods shown in FIG7 and FIG8 , it can be understood that they can limit the relative position of the docking member 24 and the limiting member 23 along the axial direction of the torque receiving member 22 after assembly. Of course, the connection methods shown in FIG7 and FIG8 can also be applied to the connection between the connecting member 25 and the limiting member 23, and the present invention is not limited to this.

[0076] Of course, the above embodiment is merely an example of the first limiting groove 71 and the first protrusion 72 and is not intended to be limiting. In other embodiments, the first limiting groove 71 may be an annular groove integrally formed on the connector 25, and the first protrusion 72 of the limiting member 23 may be engaged into the first limiting groove 71 through elastic deformation, thermal expansion and contraction, shape memory, or integral processing, the present invention being not limited thereto. Optionally, since the connector 25 is already rotatable relative to the limiting member 23, the docking member 24 and the limiting member 23 may be fixedly connected so as to rotate synchronously, for example, by welding, fusion, or gluing, to facilitate assembly and simplify the structure.

[0077] In other embodiments, corresponding second limiting grooves and second protrusions may be provided on the docking member 24 and the limiting member 23, and the docking member 24 and the limiting member 23 may be configured to be rotatably connected. In this case, the connecting member 25 and the limiting member 23 may be configured to be fixedly connected so as to rotate synchronously. Of course, in other embodiments, corresponding first limiting grooves 71 and first protrusions 72 may be provided on the connecting member 25 and the limiting member 23, and corresponding second limiting grooves and second protrusions may be provided on the docking member 24 and the limiting member 23. These will not be described in detail here.

[0078] Optionally, as shown in FIG5 , the stopper 23 includes a cylindrical section 231 that surrounds the torque transmission member 21 and shields the torque transmission member 21 along its axis. The cylindrical section 231 may be cylindrical, with a length along its axis greater than the length of the torque transmission member 21, and is capable of shielding the entire torque transmission member 21 along its axis (meaning that the distal end of the cylindrical section 231 extends beyond the distal end of the torque transmission member 21, while the proximal end of the cylindrical section 231 extends beyond the proximal end of the torque transmission member 21). In addition to serving as a portion of the stopper 23 to limit the relative position of the docking member 24 and the connector 25, the cylindrical section 231 also serves as a protective sheath, shielding the torque transmission member 21 along its axis to prevent direct contact between human tissue and the torque transmission member 21. In this embodiment, the torque transmission member 21 comprises a torque spring. Adjacent turns of the torque spring have a certain gap between them. If the torque spring were completely uncovered, human tissue could be entangled between the adjacent turns of the torque spring in some cases, potentially causing harm. The cylindrical section 231 shields the torque transmission member 21, thus avoiding this problem.

[0079] Please refer to Figures 5 and 6a to 6c. The docking member 24 includes a support portion 241 extending along its own radial direction, and the distal end of the cylindrical section 231 (i.e., the left end of the cylindrical section 231 in Figure 5) is connected to the support portion 241; the support portion 241 has a first through hole 242 and / or the cylindrical section 231 has a second through hole (not shown); please refer to Figures 4 and 5, the limiting member 23 also includes a necking section 232 arranged at the proximal end of the cylindrical section 231, the necking section 232 narrows in a direction away from the support portion 241 (to the right in Figure 5), and the necking section 232 has a third through hole 233; the first through hole 242 and / or the second through hole are connected to the third through hole 233 through the first inner cavity 230 of the cylindrical section 231.

[0080] In this example, the support portion 241 is a circular plate-like member extending radially from the docking member 24, and the torque receiving member 22 is vertically disposed at the center of the support portion 241. The tapered section 232 is tapered, gradually narrowing in the direction away from the support portion 241, and is connected to the first protrusion 72 at a position corresponding to the first limiting groove 71. The arrangement of the tapered section 232 gradually narrowing in the direction away from the support portion 241 is conducive to reducing the resistance parallel to the axial direction encountered by the torque transmission mechanism 2 when moving in the blood. The inner diameter of the cylindrical section 231 matches the outer diameter of the support portion 241, and the cylindrical section 231 can be sleeved on the outer circumference of the support portion 241 and then fixed by welding, welding or gluing. The cylindrical section 231 has a first inner cavity 230, and the torque receiving member 22 and the torque transmission member 21 are both disposed in the first inner cavity 230. The outer diameters of the torque receiving member 22 and the torque transmitting member 21 are smaller than the inner diameter of the cylindrical section 231 , and a certain gap exists between the torque transmitting member 21 and the cylindrical section 231 .

[0081] Furthermore, as shown in Figures 6a to 6c, the first through-hole 242 can be, for example, formed through the support portion 241 in a direction parallel to the axis of the support portion 241. The second through-hole can be, for example, formed through the sidewall of the cylindrical section 231 in a radial direction of the cylindrical section 231. The third through-hole 233 can, for example, be formed through the tapered sidewall of the tapered section 232. It should be noted that the first through-hole 242 on the support portion 241 and the second through-hole on the cylindrical section 231 can be provided either separately or simultaneously.

[0082] With this configuration, the first through-hole 242 and / or the second through-hole can communicate with the third through-hole 233 through the first inner cavity 230. In practical applications, the passage from the first through-hole 242 and / or the second through-hole to the third through-hole 233 is used to facilitate blood circulation, reduce or prevent the formation of blood clots or thrombi within the first inner cavity 230, and further reduce or prevent blood clots or thrombi from flowing into the heart through the first through-hole 242, the second through-hole, the third through-hole 233, or other gaps. The torque transmission mechanism 2 often needs to advance and retreat within a tubular body (such as a blood vessel, a guide sheath, or a housing 6). The inner diameter of these tubular bodies is often similar to that of the torque transmission mechanism 2. Therefore, liquids (such as blood, contrast agent, or saline) at both ends of the torque transmission mechanism 2's axis may create resistance to the advancement and retreat of the torque transmission mechanism 2. The provision of the first through-hole 242 and / or the passage from the second through-hole to the third through-hole 233 allows the liquid in these tubular bodies to circulate, thereby eliminating the resistance to the advancement and retreat of the torque transmission mechanism 2. Optionally, the number of first through-holes 242 is preferably two or more, such as two, four, six, or eight. The diameter of the first through-holes 242 can be selected from 0.6 mm to 1.5 mm, preferably 0.8 mm, 1.0 mm, or 1.2 mm. The number of third through-holes 233 is preferably two or more, such as two, four, six, or eight. The diameter of the third through-holes 233 is preferably no greater than 2 mm. More preferably, the first through hole 242 , the second through hole and the third through hole 233 may be arranged at even intervals in the circumferential direction, thereby ensuring that the blood flow velocity in the first cavity 230 is relatively consistent.

[0083] In other embodiments, the first through hole 242 and the second through hole may not be provided, and only the third through hole 233 may be provided, or the first through hole 242 and the third through hole 233 may not be provided, and only the second through hole may be provided, which will not be repeated here.

[0084] Please continue to refer to Figure 5, and in combination with Figures 6a to 6c, optionally, the docking member 24 has a second inner cavity 240 for docking with the implantable medical device 1, and the distal end of the second inner cavity 240 (i.e., the left end of the second inner cavity 240 in Figure 5) is open, allowing the implantable medical device 1 to move in and out along the axial direction of the docking member 24; when the proximal end of the implantable medical device 1 (such as the proximal end 12 of the implantable medical device 1 in Figure 1) is accommodated in the second inner cavity 240, the second inner cavity 240 is also used to limit the circumferential rotation of the implantable medical device 1. Since the torque transmission mechanism 2 provided in this embodiment does not itself need to be separated to limit the transmission of torque, the torque transmission mechanism 2 needs to be able to be easily separated or connected to the implantable medical device 1 to facilitate the implantation or recovery of the implantable medical device 1. By configuring the distal end of the second inner cavity 240 to be open, there will be no restriction on the implantable medical device 1 along the axial direction of the implantable medical device 1, and the axial position of the implantable medical device 1 is only limited by the safety wire 5. If there is no restriction of the safety wire 5, the implantable medical device 1 can freely enter and exit the second inner cavity 240 along the axial direction of the docking piece 24. With such a configuration, after the implantable medical device 1 is screwed into the ventricular septum, even if the inner sheath 4 is misoperated (such as retracted), since only the safety wire 5 is connected to the implantable medical device 1 at this time, the implantable medical device 1 and the torque transmission mechanism 2 are separated. Therefore, the inner sheath 4 will only drive the torque transmission mechanism 2 to move proximally, and will not drive the implantable medical device 1 to be pulled out from the ventricular septum, thereby eliminating the risk of damage to the ventricular septum. When the torque transmission mechanism 2 is detached from the implantable medical device 1, the process of reconnecting the torque transmission mechanism 2 to the implantable medical device 1 only requires the second inner cavity 240 to be placed on the proximal end 12 of the implantable medical device 1 along the axial direction of the docking piece 24. This is very convenient and allows the implantable medical device 1 to be recovered for a second implant when the first implant does not meet the requirements.

[0085] Optionally, as shown in FIG5 , the torque transmission member 21 has a fourth through hole 211 extending along its own axis, and the torque receiving member 22 has a fifth through hole 221 extending along its own axis. In one embodiment, the torque transmission member 21 includes a torque spring, and the fourth through hole 211 is an inner hole formed by the coiling of the torque spring. The torque receiving member 22 can be a circular tubular member, and the fifth through hole 221 is an inner hole of the tubular member. The connecting member 25 has a sixth through hole 253 extending along its own axis. The sixth through hole 253, the fourth through hole 211, and the fifth through hole 221 are coaxially connected, and are used to allow the safety wire 5 to pass through.

[0086] The diameter of the fifth through hole 221 can be selected from 0.6 mm to 1.2 mm, preferably 0.6 mm, 0.8 mm, or 1.0 mm. Furthermore, the docking member 24 is provided with a guiding slope 243 at the distal end of the fifth through hole 221 to form a trumpet shape. The trumpet-shaped structure gradually increases in size away from the connecting member 25 to facilitate the retraction of the safety wire 5.

[0087] In another embodiment, the torque transmission member 21 can also be a cylindrical rubber tube and a circular hard sleeve that are sleeved and fixed together, and the hard sleeve is sleeved outside the cylindrical rubber tube. The torque receiving member 22 can be a circular tubular member, and the distal end of the cylindrical rubber tube is sleeved on the torque receiving member 22. At this time, the fourth through hole 211 is the inner hole of the cylindrical rubber tube, and the fifth through hole 221 is the inner hole of the tubular member.

[0088] Please refer to Figures 6a to 6c. Optionally, the cross section of the second inner cavity 240 has a first reference axis A1 and a second reference axis A2 passing through the center of the cross section, and the first reference axis A1 and the second reference axis A2 are perpendicular; wherein the cross section is symmetrical about the first reference axis A1, the cross section is symmetrical about the second reference axis A2, and the size of the cross section in the direction of the first reference axis A1 is different from the size of the cross section in the direction of the first reference axis A2. Preferably, the cross-sectional shape of the second inner cavity 240 is adapted to the outer contour shape of the proximal portion 12 of the implantable medical device 1. The size of the cross section of the second inner cavity 240 in the direction of the first reference axis A1 is different from the size in the direction of the first reference axis A2, so that the proximal portion 12 can achieve torque transmission after being inserted into the second inner cavity 240.

[0089] Because the cross-section of the second inner cavity 240 is identical on both sides of the first reference axis A1 and the second reference axis A2, machining and torque transmission are facilitated. This ensures that the proximal portion 12 of the implantable medical device 1 can smoothly and coaxially and centrally enter the second inner cavity 240, minimizing friction or interference between the safety wire 5 and through-holes such as the guide bevel 243 and the fifth through-hole 221 during entry of the proximal portion 12 into the second inner cavity 240.

[0090] The docking member 24 is not limited to docking with the implantable medical device 1 by providing a non-circular second inner cavity 240 as shown in the above embodiment. Referring to Figures 9 and 10, in another exemplary embodiment, the distal end of the docking member 24 has a plurality of grooves 244 for docking with the proximal portion 12 of the implantable medical device 1. The plurality of grooves 244 are circumferentially arranged around the axis of the docking member 24. The grooves 244 are configured to allow the implantable medical device 1 to be inserted along the axis of the docking member 24 to limit circumferential rotation of the implantable medical device 1. Preferably, the plurality of grooves 244 are evenly arranged circumferentially around the axis of the docking member 24. It can be understood that the proximal portion 12 of the implantable medical device 1 has a convex tooth adapted to at least one groove 244, and the number of grooves 244 is greater than or equal to the number of convex teeth, so that the convex teeth of the proximal portion 12 can be snapped into the corresponding grooves 244, thereby realizing the docking of the docking member 24 with the implantable medical device 1, and after the two are docked, the relative circumferential rotation can be restricted, so that they can be used to transmit torque.

[0091] When there is at least one convex tooth but the number is less than the number of grooves 244, the convex tooth only cooperates with one of the grooves 244 to realize the torque transmission between the docking piece 24 and the implantable medical device 1. Since the convex tooth can match with any groove 244, the difficulty of circumferential alignment between the implantable medical device 1 and the docking piece 24 is reduced.

[0092] When there are multiple protruding teeth and the same number of grooves 244 , the protruding teeth and the grooves 244 correspond to each other in a one-to-one manner and cooperate with each other to achieve torque transmission between the docking member 24 and the implantable medical device 1 .

[0093] The embodiment of the present invention further provides a method for assembling a torque transmission mechanism 2, which is used to assemble the torque transmission mechanism 2 described above. The method for assembling the torque transmission mechanism 2 includes:

[0094] Step S1: sleeve the torque transmission component 21 onto the torque receiving component 22;

[0095] Step S2: performing a torque test on the torque transmitting member 21 and the torque receiving member 22, applying a torque greater than the rated value to the torque transmitting member 21, and if the torque transmitting member 21 rotates around the torque receiving member 22, the torque test is passed;

[0096] Step S3: After passing the torque test, the limiter 23 is connected to the torque transmission member 21 and the torque receiving member 22, respectively, to limit the position of the torque transmission member 21 relative to the torque receiving member 22 along the axis of the torque receiving member 22. Optionally, the connection between the limiter 23 and the torque receiving member 22 can be achieved indirectly, for example, through a docking member 24. In one exemplary embodiment, the step of connecting the limiter 23 and the torque receiving member 22 includes: sleeve-mounting the cylindrical section 231 of the limiter 23 around the outer periphery of the support portion 241 of the docking member 24, and then welding, fusing, or gluing the connection to form a fixed connection between the limiter 23 and the docking member 24 (in some preferred examples, this can be a snap-fit ​​connection or a threaded connection, etc.). Based on the coaxial fixed connection between the docking member 24 and the torque receiving member 22, the limiter 23 is connected to the torque receiving member 22.

[0097] Optionally, the assembly method of the torque transmission mechanism 2 further includes:

[0098] Step Sa1: Before the torque transmission member 21 is sleeved on the torque receiving member 22, the connecting member 25 is assembled and connected to the proximal end of the torque transmission member 21. The proximal end of the torque transmission member 21 is preferably fixedly connected to the connecting member 25, such as by welding, fusion or gluing.

[0099] Step Sa2: After passing the torque test, the engaging member 24 disposed at the distal end of the torque receiving member 22 is fixedly connected to the limiting member 23. The first protrusion 72 of the limiting member 23 is then installed into the first limiting groove 71 of the connecting member 25, thereby rotatably connecting the limiting member 23 and the connecting member 25. The specific configuration of Step Sa2 may depend on the structures of the engaging member 24 and the limiting member 23.

[0100] The step of installing the first protrusion 72 of the limit member 23 into the first limit groove 71 of the connecting member 25 in the aforementioned step Sa2 so that the limit member 23 and the connecting member 25 are rotatably connected specifically includes: movably sleeved the limit member 23 on the main body 250 of the connecting member 25 from the proximal end to the distal end, after the first protrusion 72 abuts against the limit platform 251, then installing the limit block 252 on the main body 250 from the proximal end to the distal end, to a position close to or abutting against the first protrusion 72, and then fixing the limit block 252 to the main body 250 and the inner sheath 4, such as welding, melting or gluing, so that the first limit groove 71 is formed between the limit platform 251 and the limit block 252, and the first protrusion 72 is engaged in the first limit groove 71, so that the limit member 23 and the connecting member 25 are rotatably connected, and at the same time limit the axial position of the limit member 23 and the connecting member 25.

[0101] It should be noted that the above-mentioned assembly method of the torque transmission mechanism 2 can be applied in the production stage, testing stage or preoperative preparation stage of the torque transmission mechanism 2, that is, during the operation, the doctor no longer needs to temporarily assemble the torque transmission mechanism 2, which effectively reduces the operation time and improves the success rate of the operation.

[0102] The following describes the usage of the torque transmission mechanism 2 and the delivery device provided in this embodiment with reference to an example of an application scenario:

[0103] First, assemble the implantable medical device 1 into the second inner cavity 240 of the docking piece 24 (corresponding to the embodiments of Figures 6a to 6c), or engage the proximal end 12 of the implantable medical device 1 with the groove 244 (corresponding to the embodiments of Figures 9 and 10), and move the inner sheath 4 toward the proximal end (i.e., from left to right in Figure 1) so that the torque limiting structure 2 and the implantable medical device 1 enter the shell 6 for storing the implantable medical device 1.

[0104] Insert the shell 6 into the guide sheath with an established channel. When the shell 6 is fully extended from the guide sheath into the right atrium, operate the outer sheath 3 so that the shell 6 crosses the tricuspid valve and smoothly enters the right ventricle. Inject contrast agent to observe the position of the shell 6 in the right ventricle and determine whether the shell 6 is perpendicular to the ventricular septum and adjust it. The contrast agent can overflow from several through holes of the torque limiting structure 2 (such as the first through hole 242, the third through hole 233, the fourth through hole 211, the fifth through hole 221 and the sixth through hole 253, etc.), and then pass through the gap between the torque limiting structure 2 and the shell 6, and finally be ejected from the distal end of the shell 6 (i.e., the left end of the shell 6 in Figure 3). Push the inner sheath 4 so that the distal end 11 of the implantable medical device 1 is completely extended out of the shell 6, and rotate the inner sheath 4 (such as clockwise) to drive the docking piece 24 and the implantable medical device 1 to rotate. Use X-rays to observe the number of rotations of the implantable medical device 1. For example, after rotating 2 circles, continue to rotate the inner sheath 4 to observe whether the implantable medical device 1 continues to rotate. Under normal circumstances, the distal end 11 of the implantable medical device 1 has been roughly screwed into a sufficient depth after rotating 2 circles, and the resistance torque of the ventricular septum to the distal end 11 is already large. The torque limiting structure 2 begins to work, and the torque transmission part 21 begins to rotate around the torque receiving part 22, thereby limiting the larger torque from being transmitted to the docking piece 24.

[0105] Withdraw the shell 6 and the torque limiting structure 2 into the right atrium or the inferior vena cava, leaving only the safety wire 5 connected to the implantable medical device 1, and test the electrical performance of the implantable medical device 1. If the electrical performance meets the requirements, the safety wire 5 can be separated from the implantable medical device 1 (such as rotating the safety wire 5 counterclockwise to separate it from the proximal end 12 of the implantable medical device 1). If the electrical performance does not meet the requirements, it is necessary to push the torque limiting structure 2 and the shell 6 along the safety wire 5 into the right ventricle again, so that the proximal end of the implantable medical device 1 is connected to the docking piece 24 again, rotate the inner sheath 4 counterclockwise, and drive the distal end 11 of the implantable medical device 1 to rotate counterclockwise out of the ventricular septum, and reposition the implanted implantable medical device 1 until the electrical performance test meets the design requirements, then separate the safety wire 5 from the implantable medical device 1, withdraw the entire delivery device and guide sheath, and complete the operation.

[0106] In summary, in the torque transmission mechanism, assembly method, and delivery device for an implantable medical device provided by the present invention, the torque transmission mechanism includes a torque transmission member, a torque receiving member, and a limiter. The torque transmission member is axially sleeved around the outer periphery of the torque receiving member and is used to transmit torque to the torque receiving member. When the torque of the torque transmission member is not greater than a rated value, the torque of the torque receiving member is equal to the torque of the torque transmission member. When the torque of the torque transmission member is greater than the rated value, the torque transmission member rotates around the torque receiving member to ensure that the torque of the torque receiving member is not greater than the rated value. The limiter is used to limit the axial position of the torque transmission member and the torque receiving member. With this configuration, based on the arrangement of the torque transmission member and the torque receiving member, when the torque of the torque transmission member is greater than the rated value, it will rotate and slip around the torque receiving member, thereby ensuring that the torque transmission member can only transmit torque that does not exceed the rated value to the torque receiving member. Furthermore, the torque transmission member and the torque receiving member do not need to be separated, eliminating gaps caused by separation failure. The setting of the limiter ensures that the torque transmission member and the torque receiving member will not separate along the axial direction, ensuring the reliability of the entire torque transmission mechanism and eliminating the risk of scratching the myocardial tissue after the torque transmission member and the torque receiving member are separated.

[0107] It should be noted that the above embodiments can be combined with each other. The above description is only a description of the preferred embodiments of the present invention and does not limit the scope of the present invention. Any changes and modifications made by ordinary technicians in the field of the present invention based on the above disclosure are within the scope of protection of the present invention.

Claims

1. A torque transmission mechanism, characterized in that: The torque transmission mechanism is used to drive the implantable medical device to rotate and implant it at the target position; the torque transmission mechanism includes: a torque transmission member, a torque receiving member and a limit member; The torque transmission member is sleeved on the outer periphery of the torque receiving member along the axial direction of the torque receiving member, and the torque transmission member is used to receive torque and transmit torque to the torque receiving member; when the torque of the torque transmission member is not greater than the rated value, the torque transmission member drives the torque receiving member to rotate synchronously; when the torque of the torque transmission member is greater than the rated value, the torque transmission member rotates around the torque receiving member so that the torque of the torque receiving member is not greater than the rated value; the limit member is used to limit the position of the torque transmission member relative to the torque receiving member along the axial direction of the torque receiving member.

2. The torque transmission mechanism according to claim 1, characterized in that: It also includes a docking member and a connecting member. The docking member is arranged at the distal end of the torque receiving member along the axial direction of the torque receiving member; and the connecting member is arranged at the proximal end of the torque transmitting member along the axial direction of the torque transmitting member.

3. The torque transmission mechanism according to claim 2, characterized in that: The limiting member is connected to the docking member and the connecting member respectively; wherein the docking member and / or the connecting member are rotatably connected around the limiting member, and the docking member limits the position of the limiting member along the axial direction of the torque receiving member, and the connecting member limits the position of the limiting member along the axial direction of the torque transmitting member.

4. The torque transmission mechanism according to claim 3, characterized in that: One of the connecting member and the limiting member has a first limiting groove arranged circumferentially, and the other has a first protruding portion arranged circumferentially, and the first protruding portion is engaged in the first limiting groove to limit the relative positions of the connecting member and the limiting member along the axial direction of the torque transmission member; and / or; One of the docking member and the limiting member has a circumferentially arranged second limiting groove, and the other has a circumferentially arranged second protrusion, which is engaged in the second limiting groove to limit the relative positions of the docking member and the limiting member along the axial direction of the torque receiving member.

5. The torque transmission mechanism according to claim 3, characterized in that: The docking member is fixedly connected, snap-connected or threadedly connected to the limiting member; the connecting member has a first limiting groove arranged circumferentially, and the limiting member has a first circumferentially arranged protrusion, which is engaged with the first limiting groove so that the limiting member can be rotatably connected to the connecting member around the connecting member.

6. The torque transmission mechanism according to claim 2 or 3, characterized in that: The limiting member includes a cylindrical section, which surrounds the torque transmission member and shields the torque transmission member in the axial direction of the torque transmission member.

7. The torque transmission mechanism according to claim 6, characterized in that: The docking piece includes a support portion extending along its own radial direction, and the distal end of the cylindrical section is connected to the support portion; the support portion has a first through hole and / or the cylindrical section has a second through hole; the limiting piece includes a tapered section arranged at the proximal end of the cylindrical section, the tapered section narrows in a direction away from the support portion, and the tapered section has a third through hole; the first through hole and / or the second through hole are connected to the third through hole through the first inner cavity of the cylindrical section.

8. The torque transmission mechanism according to claim 1, characterized in that: It also includes a docking piece arranged at the distal end of the torque receiving piece, the docking piece has a second inner cavity for docking with the implantable medical device, the distal end of the second inner cavity is open, allowing the implantable medical device to move in and out along the axial direction of the docking piece; when the proximal end of the implantable medical device is accommodated in the second inner cavity, the second inner cavity is also used to limit the circumferential rotation of the implantable medical device.

9. The torque transmission mechanism according to claim 8, characterized in that: The cross-section of the second inner cavity has a first reference axis and a second reference axis passing through the center of the cross-section, and the first reference axis is perpendicular to the second reference axis; wherein the cross-section is symmetrical about the first reference axis, the cross-section is symmetrical about the second reference axis, and the size of the cross-section in the direction of the first reference axis is different from the size of the cross-section in the direction of the first reference axis.

10. The torque transmission mechanism according to claim 1, characterized in that: It also includes a docking piece arranged at the distal end of the torque receiving piece, the docking piece has a plurality of grooves for docking with the implantable medical device, and the plurality of grooves are circumferentially arranged around the axis of the docking piece; the grooves are used for the implantable medical device to be inserted along the axial direction of the docking piece to limit the circumferential rotation of the implantable medical device.

11. The torque transmission mechanism according to claim 1, characterized in that: The torque transmission member and the torque receiving member are interference-fitted, and when the torque of the torque transmission member is not greater than a rated value, the torque transmission member and the torque receiving member are relatively fixed; When the torque of the torque transmitting member is greater than the rated value, the torque transmitting member overcomes the friction between the torque transmitting member and the torque receiving member and rotates around the torque receiving member.

12. The torque transmission mechanism according to claim 11, characterized in that: The torque transmitting member includes a torsion spring, and the torque receiving member has a cylindrical outer peripheral wall, and the torsion spring is coiled on the outer peripheral wall.

13. The torque transmission mechanism according to claim 1, characterized in that: The torque transmission member has a fourth through hole extending along its own axial direction, and the torque receiving member has a fifth through hole extending along its own axial direction. The fourth through hole and the fifth through hole are used for passing the safety wire.

14. A method for assembling a torque transmission mechanism, for assembling the torque transmission mechanism according to any one of claims 1 to 13, characterized in that: include: Sleeve the torque transmission member on the torque receiving member; Performing a torque test on the torque transmission member and the torque receiving member, applying a torque greater than the rated value to the torque transmission member, and if the torque transmission member rotates around the torque receiving member, the torque test is passed; After the torque test is passed, the limiter is connected to the torque transmission member and the torque receiving member respectively to limit the torque transmission member relative to the torque receiving member along the torque receiving member. The position of the part in the axial direction.

15. The method for assembling a torque transmission mechanism according to claim 14, characterized in that: Also includes: Before the torque transmission member is sleeved on the torque receiving member, a connecting member is assembled and connected with the proximal end of the torque transmission member; After passing the torque test, the docking piece arranged at the distal end of the torque receiving piece is fixedly connected to the limiting piece, and then the first protrusion of the limiting piece is installed into the first limiting groove of the connecting piece, so that the limiting piece and the connecting piece are rotatably connected.

16. A delivery device for an implantable medical device, characterized in that: It comprises a torque transmission mechanism according to any one of claims 1 to 13, and further comprises an outer sheath, an inner sheath and a safety wire; The inner sheath tube can be movably inserted into the outer sheath tube; the safety wire can be movably inserted into the inner sheath tube and the torque transmission mechanism; the inner sheath tube is connected to the torque transmission member of the torque transmission mechanism and is used to transmit torque to the torque transmission member to drive the torque receiving member of the torque transmission mechanism to move; The distal end of the torque transmission mechanism is used to be detachably connected to the implantable medical device, and when the torque receiving member of the torque transmission mechanism is connected to the implantable medical device, the circumferential rotation of the implantable medical device is restricted; The safety wire is used to be detachably connected to the implantable medical device.

17. An implantable medical system, characterized in that: The system includes a delivery device as described in claim 16 and an implantable medical device, wherein the distal portion of the implantable medical device is used to be implanted into a target location, and the proximal portion of the implantable medical device is used to be detachably connected to the delivery device, thereby delivering and implanting the implantable medical device into the target location through the delivery device.

Images