Handle and medical catheter

Abstract

The utility model provides a handle and medical catheter, the handle includes: limit casing, screw and drive component, the drive component is rotatablely provided around the axis and with the screw thread connection, the drive component is limited by limit casing along the axis movement, the drive component is in the screw thread connection with the screw thread connection with the screw thread connection with the screw thread connection with the screw thread connection with the screw thread connection with the screw thread connection with the screw thread connection. The screw rod is limited by the limiting shell to rotate around the axis, so that when the driving assembly rotates, the screw rod moves in the direction close to the driving assembly or away from the driving assembly along the axis. The screw rod is used for fixing the needle assembly and drives the needle assembly to move along the axis through movement. Through the handle provided by the utility model, the needle assembly can effectively withdraw and retract the needle, so that the ablation depth and accuracy of the catheter can be ensured.

Description

Technical Field

[0001] The utility model relates to the field of medical technology, in particular to a medical catheter for ventricular septal ablation and a handle thereof. Background Art

[0002] Hypertrophic Obstructive Cardiomyopathy (HOCM) is a disease characterized by asymmetric hypertrophy of the ventricular septum and left ventricular outflow tract obstruction, which reduces the amount of blood pumped by the heart to the body and eventually leads to heart failure. At the same time, lesions in the hypertrophic myocardium may also lead to abnormal cardiac conduction and severe arrhythmia, affecting the patient's quality of life and even threatening his life. It is one of the important causes of sudden cardiac death.

[0003] Septal volume reduction is the most effective treatment for severe obstruction. Traditional measures include surgical septal myectomy and percutaneous septal chemical ablation. Septal myectomy is the standard method for the treatment of HOCM in the past, but it requires surgical thoracotomy, which is traumatic and high-risk. Percutaneous septal chemical ablation can be used as an alternative to surgical septal myectomy, but this method relies on the presence of appropriate arterial septal branches. Due to anatomical limitations, about 5% to 15% of patients cannot undergo this treatment. In addition, due to factors such as the uncertainty of the range of ablation damage, its clinical application has not been widely promoted.

[0004] Radiofrequency catheter ablation is a vascular interventional technique with the advantages of less trauma and faster recovery. It can effectively treat some patients who cannot tolerate surgery or have lost the opportunity for surgery or are drug-resistant. It can accurately locate the site of ventricular septal hypertrophy through a three-dimensional mapping system and ultrasound, release radiofrequency energy to cause the myocardial contractility to lose, thereby eliminating or alleviating outflow tract obstruction and achieving the purpose of treatment. However, the maximum site of ventricular septal hypertrophy can reach more than 30mm, so the ablation depth of traditional radiofrequency ablation catheters is not enough to achieve effective treatment. Utility Model Content

[0005] The utility model aims to provide a handle and a medical catheter to solve the problem that the ablation depth of a traditional mapping / radiofrequency ablation catheter is insufficient to achieve an effective treatment purpose.

[0006] In order to solve the above problems, the utility model provides a handle for a medical catheter, the handle comprising: a limiting housing, a screw rod and a driving assembly;

[0007] The driving assembly is rotatably arranged around an axis and is threadedly connected to the screw rod. The driving assembly is restricted by the limiting housing to move along the axis, and the screw rod is restricted by the limiting housing to rotate around the axis, so that when the driving assembly rotates, the screw rod moves along the axis toward or away from the driving assembly;

[0008] The screw is used to fix the needle assembly and drive the needle assembly to move along the axis by moving.

[0009] Optionally, in the handle, the drive assembly includes a sleeve and a knob, the inner wall of the sleeve is threadedly connected to the screw, the knob is detachably sleeved on the sleeve, the knob is rotatably arranged around the axis, the sleeve is restricted by the limiting shell to move along the axis, and follows the knob when the knob rotates, and the screw moves along the axis as the sleeve rotates.

[0010] Optionally, in the handle, the inner wall of the limiting shell has a first limiting structure and a second limiting structure, the distal end of the screw extends out of the sleeve, and the distal end of the screw has a third limiting structure, the distal end of the sleeve extends out of the knob, and the distal end of the sleeve has a fourth limiting structure, the third limiting structure is matched with the first limiting structure to limit the rotation of the screw around the axis, and the fourth limiting structure is matched with the second limiting structure to limit the movement of the sleeve along the axis.

[0011] Optionally, in the handle, the distal end of the screw has a first diameter expansion portion, and the first diameter expansion portion remains outside the distal end of the sleeve, and when the screw moves toward the proximal end until the first diameter expansion portion abuts against the distal end of the sleeve, the screw is restricted from continuing to move toward the proximal end;

[0012] The distal end of the sleeve has a second enlarged diameter portion, and the second enlarged diameter portion remains outside the distal end of the knob;

[0013] The first diameter-enlarging portion has the third limiting structure, and the second diameter-enlarging portion has the fourth limiting structure.

[0014] Optionally, in the handle, the first limiting structure is a plurality of grooves sequentially distributed around the axis, the third limiting structure is a plurality of protrusions sequentially distributed along the circumferential direction, the plurality of protrusions are inserted into the plurality of grooves in a one-to-one correspondence, and the limiting housing limits the rotation of the screw rod;

[0015] The second limiting structure includes an annular groove arranged along the circumferential direction, and the fourth limiting structure includes a convex ring arranged along the circumferential direction, and the convex ring is inserted into the annular groove, so that the limiting shell limits the movement of the sleeve along the axis.

[0016] Optionally, in the handle, the limiting shell includes an upper shell and a lower shell, and the upper shell is assembled with the lower shell along a direction perpendicular to the axis.

[0017] Optionally, in the handle, the handle further includes a fixing ring, and after the upper shell and the lower shell are assembled, the proximal end of the upper shell and the proximal end of the lower shell are fixed by the fixing ring.

[0018] Optionally, in the handle, the handle also includes a main body shell, the main body shell includes a transparent cover, the limit shell is fixed to the proximal end of the transparent cover, and the inner cavity of the transparent cover provides a stroke for the screw to move along the axis toward the distal end.

[0019] Optionally, in the handle, the handle further includes a main body shell, and the handle further includes a sliding rheostat arranged in the main body shell, and the sliding portion of the sliding rheostat is used to move with the needle assembly to feedback the moving length of the needle assembly.

[0020] Optionally, in the handle, the handle also includes a push button and a fixed pulley, the push button is movably arranged in the main shell along the axis, and the distal end of the push button is located outside the distal end of the main shell, the fixed pulley is arranged in the main shell, and the proximal end of the pull wire for controlling the bending passes through the proximal end of the push button, is wound on the fixed pulley and extends toward the distal end to be fixed on the push button.

[0021] Optionally, in the handle, the distance between the fixed pulley and the axis is not greater than a desired distance.

[0022] Optionally, in the handle, the screw has an outer saline hole, an inner saline hole and a wire hole, the inner saline hole is arranged along the axis to allow the needle assembly to pass through, and the outer saline hole and the wire hole are arranged along directions parallel to the axis to allow the saline tube and the wire protective tube to pass through, respectively.

[0023] The utility model also provides a medical catheter, characterized in that it comprises: a catheter body, a needle assembly and a handle as described in any of the preceding items, wherein the handle is connected to the proximal end of the catheter body, the proximal end of the needle assembly is fixed to the screw along the axis, and the distal end of the needle assembly extends out of the distal end of the catheter body or retracts into the catheter body as the screw moves.

[0024] Optionally, in the medical catheter, the needle assembly is provided with a first pusher and a second pusher, and the first pusher and the second pusher are spaced apart by a set distance along the direction of the axis;

[0025] A sliding rheostat is provided in the handle, and the sliding portion of the sliding rheostat is located between the first pushing member and the second pushing member. When the needle assembly moves to abut against the first pushing member or the second pushing member, the sliding rheostat is driven to move to detect the moving length of the needle assembly.

[0026] Optionally, in the medical catheter, a distance between the first pushing member and the second pushing member is 1 mm to 3 mm.

[0027] Optionally, in the medical catheter, the catheter body includes a distal bendable section, the distal bendable section is connected to the handle via a pull wire, and the handle moves axially to drive the pull wire to move, thereby controlling the bending shape of the distal bendable section;

[0028] A fixed pulley is arranged in the handle, and under the guidance of the fixed pulley, the distance between the moving route of the pull wire and the axis is not greater than the expected distance.

[0029] In summary, the handle includes: a limiting shell, a screw and a driving assembly, the driving assembly is rotatably arranged around an axis and is threadedly connected to the screw, the driving assembly is limited by the limiting shell to move along the axis, and the screw is limited by the limiting shell to rotate around the axis, so that when the driving assembly rotates, the screw moves along the axis toward or away from the driving assembly; the screw is used to fix the needle assembly and drive the needle assembly to move along the axis by moving. The handle provided by the utility model enables the needle assembly to be effectively removed and retracted, thereby ensuring the ablation depth and accuracy of the catheter. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Those skilled in the art will appreciate that the drawings are provided for a better understanding of the present invention and do not constitute any limitation on the scope of the present invention.

[0031] Figure 1 A schematic diagram of the longitudinal section structure of the proximal end of the handle provided by an embodiment of the utility model;

[0032] Figure 2 This is a schematic diagram of the three-dimensional structure of the screw in the embodiment of the utility model;

[0033] Figure 3 This is a schematic diagram of the three-dimensional structure of the sleeve in the embodiment of the utility model;

[0034] Figure 4 This is a schematic diagram of the three-dimensional structure of the knob in the embodiment of the utility model;

[0035] Figure 5 This is a schematic diagram of the state in which the magnetic positioning sensor moves with the needle assembly in the embodiment of the utility model;

[0036] Figure 6 This is a schematic diagram of a bending control system in an embodiment of the utility model;

[0037] Figure 7 This is a schematic diagram of a cold saline perfusion system in an embodiment of the utility model;

[0038] Figure 8 This is a schematic diagram of the arrangement of the holes of the baffle plate in the transparent shell in the embodiment of the utility model;

[0039] Fig. 9 This is a schematic diagram of the arrangement of the holes of the screw rod in the embodiment of the utility model;

[0040] In the attached figure:

[0041] 1-knob; 2-fixing ring; 3-limiting housing; 4-casing; 5-screw; 6-transparent cover;

[0042] 7-set member; 8-needle assembly; 9-sliding resistor; 10-sliding part; 11-first push member; 12-second push member;

[0043] 13-push button; 14-guide column; 15-bolt; 16-pull wire; 17-fixed pulley;

[0044] 18-first protective tube; 19-third protective tube; 20-second protective tube;

[0045] 21-saline hole outside the baffle; 22-conductor wire; 23-saline hole inside the baffle; 24-saline hole outside the screw; 25-conductor wire hole; 26-saline hole inside the screw;

[0046] 51-first diameter expansion portion; 41-second diameter expansion portion; 42-sliding guide column; 111-guide groove;

[0047] 511- protrusion; 411- protruding ring. DETAILED DESCRIPTION

[0048] In order to make the purpose, advantages and features of the utility model clearer, the utility model is further described in detail 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, and are only used to conveniently and clearly assist in explaining the purpose of the embodiments of the utility model. In addition, the structure shown in the drawings is often a part of the actual structure. In particular, the emphasis of each drawing is different, and sometimes different scales are used.

[0049] 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 cannot be understood as indicating or suggesting relative importance or implicitly indicating the number of the indicated technical features. Thus, 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" and "the proximal end" and "the distal end" generally refer to two corresponding parts, which are not only included in the present application document, "proximal end" and "distal end" are the relative orientation, relative position, and direction of the elements or actions relative to each other from the perspective of the doctor using the medical device, although "proximal end" and "distal end" are not restrictive, but "proximal end" generally refers to the end of the medical device close to the doctor during normal operation, and "distal end" generally refers to the end that first enters the patient's body. In addition, as used in the present utility model, "installed", "connected", "connected", and one element "set" on another element should be understood in a broad sense, usually only indicating that there is a connection, coupling, matching or transmission relationship between the two elements, and the connection, coupling, matching or transmission between the two elements can be direct or indirect through an intermediate element, and cannot be understood as indicating or implying the spatial position relationship between the two elements, that is, one element can be in any orientation such as inside, outside, above, below or on one side of another element, unless the content clearly indicates otherwise.

[0050] See also Figure 1 Combined with Figure 5 The utility model provides a handle for a medical catheter, the handle comprising: a limiting shell 3, a screw 5 and a drive assembly, the drive assembly is rotatably arranged around an axis, the axis can be understood as the axis of the handle, and can also be understood as the axis of the drive assembly, the limiting shell 3 or the screw 5, and the drive assembly is threadedly connected to the screw 5, and the drive assembly is limited by the limiting shell 3 to move along the axis; the screw 5 is limited by the limiting shell 3 to rotate around the axis, so that when the drive assembly rotates, the screw 5 moves along the axis toward or away from the drive assembly; the screw 5 is used to fix the needle assembly 8, and drives the needle assembly 8 to move along the axis by moving.

[0051] The drive assembly and the screw 5 are in a spiral fit. When there is no external force constraint, if either side rotates, the other side will also rotate in the same direction, and there will be no relative displacement between the two. When the screw 5 is constrained in the rotation direction when it rotates, and the drive assembly is constrained in the front-to-back displacement direction, the screw 5 will make a relative displacement relative to the drive assembly. Therefore, when the drive assembly rotates counterclockwise, it should drive the screw 5 to rotate counterclockwise, but because the drive assembly cannot move in the front-to-back direction under the constraint of the limit housing 3, and the screw 5 cannot move in the rotation direction under the constraint of the limit housing 3, the screw 5 will make a displacement movement away from the drive assembly relative to the drive assembly.

[0052] The tail end of the needle assembly 8 is firmly connected to the screw rod 5 and will not move relative to it. Therefore, when the screw rod 5 moves away from the drive assembly, the needle assembly 8 will also move away from the drive assembly, and the manifestation at the far end of the catheter is the needle withdrawal; similarly, when the knob is rotated clockwise, the screw rod 5 will move closer to the drive assembly, and the needle assembly 8 will also move closer to the sleeve, and the manifestation at the far end of the catheter is the needle retraction.

[0053] It can be seen that, through the handle provided by the embodiment of the utility model, the needle assembly 8 can be effectively withdrawn and retracted, thereby ensuring the ablation depth and accuracy.

[0054] Correspondingly, the embodiment of the utility model further provides a medical catheter, the medical catheter comprising: a catheter body, a needle assembly 8 and a handle as described in this embodiment, the handle is connected to the proximal end of the catheter body, the proximal end of the needle assembly 8 is fixed to the screw 5 along the axis, and the distal end of the needle assembly 8 extends out of the distal end of the catheter body or retracts into the catheter body as the screw 5 moves. The handle is coaxially arranged with the catheter body, so the axis can also be understood as the axis of the catheter body.

[0055] The medical catheter provided in the embodiment of the utility model can be a catheter for ablation, mapping or ablation mapping in one. The distal end of the catheter body is connected to a head electrode, and a magnetic positioning sensor or the like can be provided on the head electrode. The needle assembly 8 can extend out of the distal end of the head electrode under the drive of the screw 5. In addition, the medical catheter has two cold saline perfusion systems, namely an internal saline passage and an external saline passage. The medical catheter includes a saline tube, and the saline tube and the needle assembly 8 are respectively matched with the internal hole structure of the screw 5 to construct the internal saline passage and the external saline passage.

[0056] Specifically, if Fig. 9As shown, the screw 5 has an inner saline hole 26 and an outer saline hole 24. The inner saline hole 26 is for the needle assembly 8 to pass through, and the outer saline hole 24 is for the saline tube to pass through. The proximal ends of the needle assembly 8 and the saline tube are connected to the Luer connector after passing through the inner saline hole 26 and the proximal ends of the outer saline hole 24, respectively. The inner cavity of the needle assembly 8 constitutes an inner saline passage. After the saline is transported from the proximal end of the needle assembly 8 to the inner cavity of the needle assembly 8, it is ejected from the needle head of the needle assembly 8. The inner cavity of the saline tube constitutes an outer saline passage. After the saline is transported from the proximal end of the saline tube to the inner cavity of the saline tube, it flows into the inner cavity of the catheter body and flows out in the gap between the needle assembly 8 and the head electrode.

[0057] The needle assembly 8 can be fixed to the saline hole 26 in the screw rod by gluing. During the movement of the screw rod 5, the needle assembly 8 moves with the movement of the screw rod 5, and the saline tube keeps its position unchanged and does not move with the screw rod 5.

[0058] In addition, please continue to see Fig. 9 Combined with Figure 8 The screw rod 5 also has a wire hole 25, and the wire hole 25 is used for the wire 22 to pass through. The wire 22 and the screw rod 5 remain relatively fixed. During the movement of the screw rod 5, the wire 22 moves with the movement of the screw rod 5.

[0059] In order to ensure the synchronization of the movement of the needle assembly 8 and the wire, the needle assembly 8 and the wire will be bonded together at the proximal end. In order to ensure the accuracy of assembly and to avoid interference and difficulty in assembly, the bonding operation needs to be performed after the limit housing 3, the screw rod 5 and the drive assembly are in place. However, in order to facilitate holding, the drive assembly needs to have a certain axial length. If the proximal bonding operation is performed after the drive assembly is connected to the screw rod 5, the operation difficulty will be increased.

[0060] In view of this, in this embodiment, preferably, the driving assembly adopts a detachable combined structure, such as Figure 1 As shown in the figure, the driving assembly includes a sleeve 4 and a knob 1. The inner wall of the sleeve 4 is threadedly connected to the screw 5. The knob 1 can be detachably sleeved on the sleeve 4. The knob 1 is rotatably arranged around the axis. In this way, after the sleeve 4 is threadedly connected to the screw 5, the wire and the saline tube are first bonded together, and then the knob 1 is sleeved on the sleeve 4, thereby achieving the purpose of reducing the difficulty of bonding.

[0061] When the driving assembly adopts a detachable combined structure, the sleeve 4 is restricted by the limit housing 3 to move along the axis, and when the knob 1 rotates, it rotates along with the knob 1, and the screw 5 moves along the axis with the rotation of the sleeve 4. In this way, when the knob 1 rotates counterclockwise, the sleeve 4 will also rotate counterclockwise, and at the same time drive the screw 5 to rotate counterclockwise. At this time, the sleeve 4 cannot move in the front-to-back direction under the constraint of the limit housing 3, and the screw 5 cannot move in the rotation direction under the constraint of the limit housing 3, and the screw 5 will move away from the sleeve 4 relative to the sleeve 4.

[0062] In this embodiment, the inner wall of the limiting shell 3 has a first limiting structure and a second limiting structure, the distal end of the screw 5 extends out of the sleeve 4, and the distal end of the screw 5 has a third limiting structure, and the distal end of the sleeve 4 has a fourth limiting structure. The third limiting structure is matched with the first limiting structure to limit the rotation of the screw 5 around the axis, and the fourth limiting structure is matched with the second limiting structure to limit the movement of the sleeve 4 along the axis.

[0063] Better, such as Figure 2 As shown, the distal end of the screw rod 5 has a first diameter expansion portion 51, and the first diameter expansion portion 51 remains outside the distal end of the sleeve 4. When the screw rod 5 moves toward the proximal end until the first diameter expansion portion 51 abuts against the distal end of the sleeve 4, the screw rod 5 is restricted from continuing to move toward the proximal end. Figure 3 As shown, the distal end of the sleeve 4 has a second diameter expansion portion 41, and the second diameter expansion portion 41 remains located outside the distal end of the knob 1, the first diameter expansion portion 51 has the third limiting structure, the second diameter expansion portion 41 has the fourth limiting structure, and the first diameter expansion portion 51 and the second diameter expansion portion 41 have approximately equal outer diameters to facilitate assembly connection with the first limiting structure and the second limiting structure of the limiting housing 3, respectively.

[0064] Optionally, the first limiting structure may include a plurality of grooves sequentially distributed in the circumferential direction, and the third limiting structure may include Figure 2 The plurality of protrusions 511 are sequentially distributed along the circumferential direction as shown in the figure, and the plurality of protrusions 511 are inserted into the plurality of grooves one by one, so that the screw 5 can only move along the axis but cannot rotate around the axis; the second limiting structure may include an annular groove arranged along the circumferential direction, and the fourth limiting structure may include as Figure 3The convex ring 411 shown in the figure is arranged circumferentially, and the convex ring 411 is inserted into the annular groove, so that the sleeve 4 can only rotate around the axis, but cannot move along the axis. It should be noted that the specific structures of the first limiting structure, the second limiting structure, the third limiting structure, and the fourth limiting structure do not constitute a limitation to the present application. In other embodiments, the first limiting structure, the second limiting structure, the third limiting structure, and the fourth limiting structure can also adopt other structural designs. It is only necessary to ensure that the cooperation of the first limiting structure and the third limiting structure enables the screw 5 to move along the axis but not to rotate, and the cooperation of the second limiting structure and the fourth limiting structure enables the sleeve to rotate but not to move along the axis.

[0065] In addition, if Figure 3 and Figure 4 As shown, a sliding guide post 42 may be provided on the surface of the sleeve 4, and a guide groove 111 may be provided on the inner wall of the knob 1. The sliding guide post 42 and the guide groove 111 are aligned so that the sleeve 4 and the knob 1 can move relative to each other along the axis while maintaining the relative position unchanged in the circumferential direction.

[0066] Preferably, the limit housing 3 includes an upper housing and a lower housing, and the upper housing is assembled with the lower housing in a direction perpendicular to the axis. After the upper housing and the lower housing are assembled, the screw 5 is restricted from rotating around the axis, and the sleeve 4 is restricted from moving along the axis. The limit housing 3 adopts a splicing structure, which can reduce the difficulty of assembly and facilitate alignment with the screw 5 and the sleeve 4. Further preferably, Figure 1 As shown, the handle further includes a fixing ring 2, and after the upper shell and the lower shell are assembled, the proximal ends of the upper shell and the lower shell are fixed by the fixing ring 2. Specifically, the proximal ends of the upper shell and the lower shell may be provided with a step, and the wall thickness of the fixing ring 2 is consistent with the height of the step. After the fixing ring 2 is sleeved on the proximal ends of the upper shell and the lower shell, the surface of the fixing ring 2 is flush with the surfaces of the upper shell and the lower shell.

[0067] In addition, the handle provided in the embodiment of the utility model further comprises a main body shell, and the distal end of the limit shell 3 can be fixed by extending into the proximal end of the main body shell. The distal ends of the upper shell and the lower shell can be provided with steps, which are used to extend into the main body shell, so that the upper shell, the lower shell and the main body shell are fixedly connected, and at the same time, the surface of the portion of the upper shell and the lower shell that does not extend into the main body shell can be flush with the surface of the main body shell.

[0068] Better, such as Figure 1As shown in , the main body shell includes a transparent cover 6, the limit shell 3 is fixed to the proximal end of the transparent cover 6, the inner cavity of the transparent cavity provides a stroke for the screw 5 to move along the axis toward the distal end, and a baffle can be set in the inner cavity of the transparent cover 6, and the baffle limits the distance that the screw 5 moves toward the distal end. When the screw 5 moves into the inner cavity of the transparent cover 6, the user can observe with the naked eye whether the screw 5 inside is displaced, so as to roughly judge whether the front end of the catheter is out of the needle.

[0069] For better, see Figure 5 The handle also includes a sliding rheostat 9 disposed in the main body shell, and a sliding portion 10 of the sliding rheostat 9 is used to move along with the movement of the needle assembly 8 to provide feedback on the movement length of the needle assembly 8 .

[0070] Specifically, a first pusher 11 and a second pusher 12 are provided on the needle assembly 8 in a direction perpendicular to the axis. The first pusher 11 and the second pusher 12 are spaced a set distance apart in the direction of the axis. The first pusher 11 and the second pusher 12 can be baffles, which are integrally formed with a set member 7. The set member 7 is sleeved on the needle assembly 8 to fix the first pusher 11 and the second pusher 12 to the needle assembly 8; the sliding portion 10 of the sliding rheostat 9 is located between the first pusher 11 and the second pusher 12. When the needle assembly 8 moves to abut against the first pusher 11 or the second pusher 12, the sliding portion 10 is driven to move. When the sliding portion 10 slides from one side to the other side, the resistance of the sliding rheostat 9 itself will change in proportion to the sliding distance. Therefore, the moving length of the needle assembly 8 can be detected by changing the resistance value of the sliding rheostat 9, and the distance of the needle being extended or retracted can be accurately reflected.

[0071] Preferably, the distance between the first pusher 11 and the second pusher 12 is designed to be 1mm to 3mm, and more preferably 2mm. The reason for this setting is that it was found during the verification process that the telescopic distance of the tail end of the needle assembly 8 is inconsistent with the telescopic distance of the head end of the needle assembly 8. Analysis found that when the needle assembly 8 is displaced in the catheter, it will inevitably rub against the inner wall of the catheter, resulting in that when the proximal end of the needle assembly 8 has been displaced, the distal end or the middle position does not fully respond or partially responds to the displacement of the proximal end due to the friction force. From a macroscopic point of view, the displacement distances of the distal and proximal ends of the needle assembly 8 are inconsistent. Through a large number of verifications, it is found that the difference in displacement distances between the distal and proximal ends of the needle assembly 8 is about 1mm to 3mm. In view of this situation, the utility model designs the distance between the first pusher 11 and the second pusher 12 to be 1mm to 3mm, and more preferably 2mm, which can compensate for the "empty stroke" caused by friction to the greatest extent, so that the needle telescopic length fed back by the sliding rheostat 9 becomes more accurate.

[0072] Furthermore, in the medical catheter provided by the embodiment of the utility model, the catheter body includes a distal bendable section, and accordingly, the handle has a bending control function, the handle is connected to the head electrode through a pull wire 16, and the handle controls the movement of the pull wire 16 to control the bending shape of the distal bendable section. Specifically, Figure 6 As shown, the handle also includes a push button 13, and the push button 13 is movably arranged along the axis under the guidance of a guide column 14. A portion of the push button 13 extends into the main body shell from the distal end of the main body shell, and the proximal end of the wire is fixed to the push button 13 after extending into the main body shell. The push button 13 moves to drive the pull wire 16 to move, thereby controlling the bending of the distal end of the catheter.

[0073] Since the displacement of the needle assembly 8 depends on the combination of the proximal end and the screw 5, and the screw 5 drives the needle assembly 8 forward or backward, the needle assembly 8 must move along the axis located in the center of the catheter or the handle, which is conducive to the transmission of force and the needle will not be easily bent when it is extended. In this case, the pull wire 16 cannot be fixed at the center of the handle, otherwise it will interfere with the needle assembly 8.

[0074] In view of this, the handle provided in the embodiment of the utility model is further provided with a fixed pulley 17 in the handle, and the pull wire 16 is guided to move in the catheter and the handle by means of the fixed pulley 17. The distal end of the pull wire 16 is fixed to the head electrode at the distal end of the catheter, and the proximal end passes through the fixed pulley 17 after entering the main body shell from the push button 13 and extends toward the distal end, and is fixed to the push button 13. The push button 13 is provided with a bolt 15, and the distal end of the pull wire 16 is fixed to the bolt 15, and the bolt 15 is fixed to the push button 13. When the push button 13 is pushed toward the distal end, the tail end of the pull wire 16 fixed on the bolt 15 will move toward the distal end along with the push button 13. At this time, the pull wire 16 fixed on the head electrode at the distal end will be subjected to a pulling force in the opposite direction (toward the proximal end). Since the outer tube of the catheter is fixed inside the guide column 14, the catheter as a whole cannot make a relative displacement, and then the distal end of the catheter forms a bend under the action of the pulling force. The greater the stroke of the push button 13, the greater the pulling force on the pull wire 16, and the greater the bending control angle; when the push button 13 returns from the distal end to the proximal end, the pulling force on the pull wire 16 becomes smaller and smaller, and the bending control angle also becomes smaller and smaller, and finally returns to a straight state. Guided by the fixed pulley 17, the pull wire 16 deviates from the axis, that is, moves away from the center, and will not interfere with the movement of the needle assembly 8.

[0075] Preferably, the distance between the fixed pulley 17 and the axis is not greater than the desired distance, so that the moving path of the pull wire 16 deviates from the axis but is close to the axis, thereby ensuring the bending control accuracy.

[0076] See also Figure 7 Preferably, the medical catheter further comprises a first protective tube 18, a second protective tube 20 and a third protective tube 19. The first protective tube 18 and the second protective tube 20 are respectively used to protect the needle assembly 8 and the saline tube. The first protective tube 18 and the second protective tube 20 are both distributed in three sections in the handle. After the needle assembly 8 passes through the proximal end of the first protective tube 18, it extends into the screw inner saline hole 26 of the screw 5. After the saline tube passes through the proximal end of the second protective tube 20, it extends into the screw outer saline hole 24 of the screw 5. The third protective tube 20 is used to protect the wire 22. The third protective tube 20 can be fixed in the wire hole 25 by glue bonding. When the needle assembly 8 is protected by the first protective tube 18, the first pusher 11 and the second pusher 12 are sleeved on the second protective tube 20 through the sleeve member 7.

[0077] In addition, in order to ensure that the needle assembly 8 can move along the axis, the saline hole 26 inside the screw 5 is set along the axis to allow the needle assembly 8 to pass through, and the saline hole 24 outside the screw and the wire hole 25 are respectively set in a direction parallel to the axis to allow the saline tube and the wire to pass through respectively. That is, the saline hole 24 outside the screw is set at the center of the screw 5, while the saline hole 24 outside the screw and the wire hole 25 are eccentrically set. In addition, in order to prevent the baffle in the transparent cover 6 from interfering with the movement of the needle assembly 8 and the saline tube, as shown in FIG. Figure 8 As shown, brine holes 21 outside the baffle and brine holes 23 inside the baffle are also provided accordingly.

[0078] The medical catheter workflow provided in this embodiment is as follows:

[0079] When the catheter enters the heart, the catheter tip reaches the lesion site by controlling the bend and cooperating with the three-dimensional device. At this time, by rotating the knob 1 on the handle, the needle assembly 8 is slowly extended. There are two ways to judge the needle out at this time: (1) by observing the forward distance of the screw 5 in the transparent cover 6 with the naked eye to roughly judge the needle out, and realize the visualization of the needle out; (2) according to the change of the resistance value of the sliding rheostat 9, the needle length is accurately calculated and displayed on the three-dimensional device. At this time, the operator can accurately judge the needle length so that the ablation needle reaches the ideal ablation depth. When ablation begins, through the cold saline perfusion system, cold saline can be released inside the needle assembly and between the needle assembly and the head electrode to achieve the purpose of cooling the lesion and reduce the risk of scab and thrombosis caused by overheating.

[0080] To sum up, the handle provided in the embodiment of the utility model enables the catheter to realize the functions of bending control, retractable needle, cold saline infusion, precise retractable needle length and retractable needle visualization, so that the catheter can effectively reach the lesion and perform needle removal and radiofrequency ablation, and at the same time can detect the retractable length of the needle assembly in real time. On the one hand, it can reduce the risk of ventricular septal puncture caused by excessive needle removal, and on the other hand, it can control the needle removal length within the optimal range, so that it can penetrate deep into the lesion to achieve deep ablation and achieve the ideal treatment goal.

[0081] In addition, it should be recognized that although the present invention has been disclosed as a preferred embodiment, the above embodiment is not intended to limit the present invention. For any technician familiar with the art, without departing from the scope of the technical solution of the present invention, the above disclosed technical content can be used to make many possible changes and modifications to the technical solution of the present invention, or modified into equivalent embodiments of equivalent changes. Therefore, any simple modification, equivalent change and modification made to the above embodiment based on the technical essence of the present invention without departing from the content of the technical solution of the present invention still falls within the scope of protection of the technical solution of the present invention.

Claims

1. A handle for a medical catheter, characterized in that: The handle comprises: a limiting housing, a screw rod and a driving assembly; The driving assembly is rotatably arranged around an axis and is threadedly connected to the screw rod. The driving assembly is restricted by the limiting housing to move along the axis, and the screw rod is restricted by the limiting housing to rotate around the axis, so that when the driving assembly rotates, the screw rod moves along the axis toward or away from the driving assembly; The screw is used to fix the needle assembly and drive the needle assembly to move along the axis by moving.

2. The handle according to claim 1, characterized in that: The driving assembly includes a sleeve and a knob, the inner wall of the sleeve is threadedly connected to the screw, the knob is detachably sleeved on the sleeve, the knob is rotatably arranged around the axis, the sleeve is restricted by the limiting shell to move along the axis, and when the knob rotates, it rotates with the knob, and the screw moves along the axis as the sleeve rotates.

3. The handle according to claim 2, characterized in that: The inner wall of the limiting shell has a first limiting structure and a second limiting structure, the distal end of the screw extends out of the sleeve, and the distal end of the screw has a third limiting structure, the distal end of the sleeve extends out of the knob, and the distal end of the sleeve has a fourth limiting structure, the third limiting structure is matched with the first limiting structure to limit the rotation of the screw around the axis, and the fourth limiting structure is matched with the second limiting structure to limit the movement of the sleeve along the axis.

4. The handle according to claim 3, characterized in that: The distal end of the screw has a first diameter expansion portion, which is kept outside the distal end of the sleeve. When the screw moves toward the proximal end until the first diameter expansion portion abuts against the distal end of the sleeve, the screw is restricted from continuing to move toward the proximal end. The distal end of the sleeve has a second enlarged diameter portion, and the second enlarged diameter portion remains outside the distal end of the knob; The first diameter-enlarging portion has the third limiting structure, and the second diameter-enlarging portion has the fourth limiting structure.

5. The handle according to claim 3 or 4, characterized in that: The first limiting structure is a plurality of grooves sequentially distributed around the axis, and the third limiting structure is a plurality of protrusions sequentially distributed along the circumferential direction, and the plurality of protrusions are inserted into the plurality of grooves in a one-to-one correspondence, so that the limiting housing limits the rotation of the screw rod; The second limiting structure includes an annular groove arranged along the circumferential direction, and the fourth limiting structure includes a convex ring arranged along the circumferential direction, and the convex ring is inserted into the annular groove, so that the limiting shell limits the movement of the sleeve along the axis.

6. The handle according to claim 1, characterized in that: The limiting housing comprises an upper shell and a lower shell, and the upper shell is assembled with the lower shell along a direction perpendicular to the axis.

7. The handle according to claim 6, characterized in that: The handle also includes a fixing ring. After the upper shell and the lower shell are assembled, the proximal end of the upper shell and the proximal end of the lower shell are fixed by the fixing ring.

8. The handle according to claim 1, characterized in that: The handle also includes a main body shell, the main body shell includes a transparent cover, the limit shell is fixed to the proximal end of the transparent cover, and the inner cavity of the transparent cover provides a stroke for the screw to move along the axis toward the distal end.

9. The handle according to claim 1, characterized in that: The handle further comprises a main body shell, and the handle further comprises a sliding rheostat arranged in the main body shell, wherein the sliding portion of the sliding rheostat is used to move along with the needle assembly to feed back the moving length of the needle assembly.

10. The handle according to claim 9, characterized in that: The handle also includes a push button and a fixed pulley. The push button is movably arranged in the main shell along the axis, and the distal end of the push button is located outside the distal end of the main shell. The fixed pulley is arranged in the main shell. The proximal end of the pull wire for controlling the bending passes through the proximal end of the push button, is wound on the fixed pulley and extends toward the distal end to be fixed on the push button.

11. The handle according to claim 10, characterized in that: The distance between the fixed pulley and the axis is no greater than a desired distance.

12. The handle according to claim 1, characterized in that: The screw has an outer saline hole, an inner saline hole and a guide wire hole. The inner saline hole is arranged along the axis to allow the needle assembly to pass through. The outer saline hole and the guide wire hole are arranged along directions parallel to the axis to allow the saline tube and the guide wire protection tube to pass through respectively.

13. A medical catheter, characterized in that: include: A catheter body, a needle assembly and a handle as described in any one of claims 1 to 12, wherein the handle is connected to the proximal end of the catheter body, the proximal end of the needle assembly is fixed to the screw along the axis, and the distal end of the needle assembly extends out of the distal end of the catheter body or retracts into the catheter body as the screw moves.

14. The medical catheter according to claim 13, wherein: The needle assembly is provided with a first pusher and a second pusher, and the first pusher and the second pusher are spaced apart by a set distance along the direction of the axis; A sliding rheostat is provided in the handle, and the sliding portion of the sliding rheostat is located between the first pushing member and the second pushing member. When the needle assembly moves to abut against the first pushing member or the second pushing member, the sliding rheostat is driven to move to detect the moving length of the needle assembly.

15. The medical catheter according to claim 14, characterized in that The distance between the first pushing member and the second pushing member is 1 mm to 3 mm.

16. The medical catheter according to claim 13, wherein: The catheter body comprises a distal bendable section, the distal bendable section is connected to the handle via a pull wire, and the handle moves axially to drive the pull wire to move, thereby controlling the bending shape of the distal bendable section; A fixed pulley is arranged in the handle, and under the guidance of the fixed pulley, the distance between the moving route of the pull wire and the axis is not greater than the expected distance.

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