Fusing snare

Abstract

The invention relates to the technical field of medical instruments, in particular to a fusible snare. Comprising a contraction coil, a guiding catheter and a handle assembly, the contraction coil comprises an annular structure, a conductive protrusion protruding outwards is arranged at one end of the annular structure, and two guide wires parallel to each other are arranged at the other end of the annular structure; the peripheral wall, except the conductive protrusions, of the annular structure is wrapped by a first insulating tube, and the peripheral walls of the two guide wires are wrapped by a second insulating tube. The ends, away from the annular structure, of the two guide wires penetrate through the guiding catheter to be connected with the handle assembly. According to the fusible snare provided by the invention, the contraction coil can be fused at any time when reaching an ideal position so as to be released, so that the damage to coronary artery and collateral circulation in the in-vitro traction process of the contraction coil is reduced, and the problem that the aortic arch is damaged due to the fact that the contraction coil is not completely released and the snare is repeatedly pulled in the withdrawing process is reduced.

Description

Technical Field

[0001] The present invention relates to the technical field of medical devices, and particularly to a fusible snare Background Art

[0002] Snares are currently widely and maturely used in percutaneous puncture for treating ventricular septal defects and patent ductus arteriosus surgeries, and the entire set of guidewires play a role in establishing a track. However, with the development of retrograde techniques for coronary artery occlusion lesions and transcatheter aortic valve replacement, snares play a good role in capturing retrograde guidewires to establish a track in the retrograde technique of chronic occlusion lesions and bending the head end of the valve delivery device to pass through the aortic arch during transcatheter aortic valve replacement. However, after the snare captures the retrograde guidewire body to establish a track, due to catheter space limitations, the contraction coil cannot be loosened in the guiding catheter, and it is easy to damage the coronary artery and collateral circulation during the process of pulling the guidewire outwards, resulting in serious consequences such as blood vessel injury or even rupture. At the same time, when performing transcatheter aortic valve replacement, after the snare assists in passing through the arch, the snare may not be able to be withdrawn from the valve end or may repeatedly pull and damage the aortic arch during withdrawal, thus causing the possibility of aortic arch injury. Therefore, to reduce related risks, a fusible snare is proposed to solve the above problems. Summary of the Invention

[0003] The purpose of the present invention is to provide a fusible snare, which can be melted and loosened at any time when the contraction coil reaches the ideal position, reducing the damage to the coronary artery and its collateral circulation during the process of pulling the guidewire out of the body, and reducing the problem of aortic arch injury caused by incomplete loosening of the contraction coil and repeated pulling of the snare during the process of withdrawing the snare.

[0004] The present invention provides a fusible snare, including a contraction coil, a guiding catheter, and a handle assembly. The contraction coil includes an annular structure, one end of the annular structure is provided with a conductive protrusion protruding outwards, and the other end of the annular structure is provided with two parallel guidewires; the outer peripheral wall of the annular structure except the conductive protrusion is wrapped with a first insulating tube; the outer peripheral walls of the two guidewires are wrapped with a second insulating tube; the ends of the two guidewires away from the annular structure pass through the guiding catheter and are connected to the handle assembly.

[0005] Further, the annular structure, the conductive protrusion, and the two guidewires are of an integrally formed structure.

[0006] Further, the two guidewires are wrapped inside a second insulating tube; the second insulating tube is connected to the first insulating tube, and the materials of the first insulating tube and the second insulating tube are both polytetrafluoroethylene.

[0007] Further, the material of the contraction coil is cobalt-chromium alloy.

[0008] Further, anti-slip patterns are provided on the outer peripheral wall of the first insulating tube.

[0009] Further, the handle assembly includes a handle rod, a sleeve is slidably connected to the handle rod, a second finger ring is detachably connected to the sleeve, a fixing block is provided inside the sleeve, and the fixing block is located inside the handle rod and connected to the guide wire.

[0010] Further, two arc-shaped plates are symmetrically provided at one end of the sleeve away from the guiding catheter, a first limiting hole is provided on the arc-shaped plate, a second limiting hole is provided on the second finger ring, and a limiting bolt passes through the first limiting hole and is threadedly connected to the second limiting hole.

[0011] Further, a second sliding groove is provided on the outer peripheral wall of the sleeve, a second sliding block is provided on the side wall of the second finger ring, and the second sliding block is located in the second sliding groove.

[0012] Further, scale lines are provided on the outer peripheral wall of the handle rod.

[0013] Further, a cable connector is provided on the side wall of the sleeve, and the cable connector is connected to the guide wire.

[0014] In summary, the present invention has the following advantages:

[0015] The technical solution of the present invention is to respectively provide a first insulating tube and a second insulating tube at positions of the shrinkage coil except for the conductive protrusions. During normal operation, capture is performed through the handle assembly. When it is necessary to release the shrinkage coil, the guide wire is electrified, and the conductive protrusions at the annular structure are melted to release. The fusible snare provided by the present invention can release the shrinkage coil at any time when it reaches the ideal position, reducing the damage to the coronary artery and its collateral circulation during the externalization process of the shrinkage coil pulled by the reverse technique in the guiding catheter in the coronary artery occlusion lesion. During transcatheter aortic valve replacement, after pulling the front end of the aortic valve delivery system over the aortic arch, the conductive protrusions are melted to reduce the problem of aortic arch damage caused by incomplete release and repeated pulling of the snare during the withdrawal process. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In order to more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the following will briefly introduce the drawings required for the description of the specific embodiments or the prior art. Obviously, the following drawings are some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0017] Figure 1 It is a schematic structural diagram of the snare in Embodiment 1 of the present invention;

[0018] Figure 2Schematic structural diagram of the shrinking coil in Embodiment 1 of the present invention;

[0019] Figure 3 Schematic structural diagram of the snare in Embodiment 2 of the present invention;

[0020] Figure 4 Cross-sectional view of the cannula in Embodiment 2 of the present invention;

[0021] Figure 5 Schematic structural diagram of the cannula in Embodiment 2 of the present invention.

[0022] Explanation of reference numerals: 1 - shrinking coil; 101 - annular structure; 102 - conductive protrusion; 103 - guide wire; 104 - first insulating tube; 105 - second insulating tube; 2 - guiding catheter; 3 - handle assembly; 301 - handle rod; 3011 - first finger ring; 302 - first sliding groove; 303 - cannula; 3031 - second sliding groove; 3032 - first slider; 3033 - fixing block; 304 - second finger ring; 3041 - second slider; 305 - cable connector; 306 - scale line; 307 - arc plate; 308 - limit bolt. Detailed implementation manners

[0023] The technical solutions of the present invention will be clearly and completely described below in conjunction with the embodiments. Obviously, the described embodiments are some, but not all, of the embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0024] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", etc. indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings. It is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus should not be construed as a limitation of the present invention.

[0025] In addition, the terms "first" and "second" are for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, features defined with "first" and "second" may explicitly or implicitly include one or more of the said features. In the description of the present invention, the meaning of "a plurality" is two or more unless otherwise specifically defined. In addition, the terms "mounted", "connected" and "coupled" should be understood in a broad sense. For example, it may be a fixed connection, a detachable connection or an integral connection; it may be a mechanical connection or an electrical connection; it may be directly connected or indirectly connected through an intermediate medium, and it may be the communication inside two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0026] Example 1

[0027] A fusing snare, as Figure 1 shown, includes a retractable coil 1, a guiding catheter 2 and a handle assembly 3. The guiding catheter 2 is connected to the handle assembly 3. The end of the retractable coil 1 passes through the guiding catheter 2 and is connected to the handle assembly 3. By operating the handle assembly 3, the retractable coil 1 can be moved along the direction of the guiding catheter 2.

[0028] As Figure 2 shown, the retractable coil 1 includes an annular structure 101. One end of the annular structure 101 is provided with a conductive protrusion 102 protruding outward. The other end of the annular structure 101 is provided with two parallel guide wires 103. The two guide wires 103, the annular structure 101 and the conductive protrusion 102 are of an integrally formed structure and are made of cobalt-chromium alloy. Among them, the position of the annular structure 101 except the conductive protrusion 102 is wrapped with a first insulating tube 104, and the outside of the guide wires 103 is wrapped with a second insulating tube 105. Two cavities for accommodating the two guide wires 103 are arranged inside the second insulating tube 105, so that the two guide wires 103 share one second insulating tube 105 (the two guide wires 103 share one insulating tube, and the two guide wires 103 can also be jointly wrapped in the same insulating tube by applying an insulating layer); one end of the second insulating tube 105 is fixedly connected to the first insulating tube 104. The materials of the first insulating tube 104 and the second insulating tube 105 are both polytetrafluoroethylene. The end of the guide wire 103 away from the annular structure 101 passes through the guiding catheter 2 and is connected to the handle assembly 3. The guiding catheter 2 can adopt a conventional 5F catheter in the art, and the guiding catheter 2 and the handle assembly 3 are connected by conventional technical means in the art.

[0029] Anti-slip lines are provided on the outer peripheral wall of the first insulating tube 104. The provision of the anti-slip lines can increase the friction between the retractable coil 1 and the corresponding instruments (such as catheters, delivery sheaths, displaced stents, etc.), prevent slipping, and enable the operation to proceed smoothly.

[0030] The handle assembly 3 includes a handle rod 301 with a hollow structure inside. The guiding catheter 2 and the handle rod 301 are connected by conventional technical means in the art. One end of the handle rod 301 away from the guiding catheter 2 is provided with a first finger ring 3011; a sleeve 303 is slidably connected to the handle rod 301. Two second finger rings 304 are symmetrically arranged on the sleeve 303. Two first sliding grooves 302 are symmetrically arranged on the side wall of the handle rod 301. Two first sliding blocks are symmetrically arranged on the inner wall of the sleeve 303. The two first sliding blocks are respectively slidably connected in the two first sliding grooves 302. A fixing block is arranged inside the sleeve 303. The fixing block is located inside the handle rod 301. Both ends of the fixing block are fixedly connected to the two first sliding blocks. The ends of the two guide wires 103 are fixedly connected to the fixing block. During operation, insert the fingers into the first finger ring 3011 and the second finger rings 304, and drive the sleeve 303 to move along the handle rod 301 through the fingers, so as to contract the shrinkage coil 1 along the guiding catheter 2.

[0031] Scale lines 306 are arranged on the outer side wall of the handle rod 301. The arranged scale lines 306 can help the operator accurately master the extending length of the snare, facilitate precise positioning during the operation, improve safety at the same time, avoid excessive insertion, and reduce the risk of damage to surrounding tissues.

[0032] Anti-slip pads are fixedly installed on the inner walls of the first finger ring 3011 and the second finger rings 304. The arranged anti-slip pads can increase the friction between the finger rings and the fingers and ensure the stability of the operation.

[0033] A cable connector 305 is installed on the side wall of the sleeve 303. The cable connector 305 is connected to the two guide wires 103. During normal operation, the shrinkage coil 1 is contracted for capture by using the guiding catheter 2 through the handle assembly 3. When it is necessary to loosen the shrinkage coil 1, the two guide wires 103 are energized through the cable connector 305, and the conductive protrusion 102 is melted and broken. The shrinkage coil 1 is loosened. If further operations are still required after loosening, a brand-new snare can be replaced for operation.

[0034] The material of the conductive protrusion 102 can also be made of fusible alloys (such as bismuth-based, tin-based, lead-based alloys, etc.) and biodegradable metal materials (such as magnesium alloys, iron alloys). After melting, the impact on the physiological environment of surrounding tissues and blood is relatively small. Polymer composites can also be used, such as carbon nanotube / polylactic acid composites. Polylactic acid has good biocompatibility and biodegradability, and carbon nanotubes endow the material with conductivity. When the heat generated by energization reaches the decomposition temperature of polylactic acid, the conductive protrusion 102 will decompose and melt, and the decomposition products are mainly harmless substances such as carbon dioxide and water, and have almost no adverse effects on surrounding tissues and blood.

[0035] The fusing working principle of the snare provided by the present invention is as follows: When the end of the guide wire 103 is electrified, according to Joule's law, the resistance of the guide wire 103 itself will generate heat during the electrification process. Since the conductive protrusion 102 is exposed and not wrapped by insulating material, heat accumulates here. As the heat accumulates continuously, when it reaches the melting point of the material of the conductive protrusion 102, the conductive protrusion 102 will be fused, thus completing the loosening action.

[0036] Embodiment 2

[0037] A fusing snare, as Figure 3 shown, the technical solution in this embodiment is basically the same as that in Embodiment 1, the difference being that: the first finger ring 3011 and the second finger ring 304 on the handle assembly 3 in this embodiment are detachable and can be replaced according to the thickness of the operator's finger.

[0038] The handle assembly 3 in this embodiment includes a handle rod 301 with a hollow structure. One end of the handle rod 301 away from the guiding catheter 2 is connected with a first finger ring 3011 by a bolt. Two first sliding grooves 302 are symmetrically arranged on the side wall of the handle rod 301. A sleeve 303 is sleeved outside the handle rod 301. Two first sliding blocks 3032 are symmetrically fixed on the inner wall of the sleeve 303, and the two first sliding blocks 3032 respectively move along the two first sliding grooves 302. A fixing block 3033 is arranged between the two first sliding blocks 3032, and the ends of the two guide wires 103 of the retractable coil 1 are fixed to the fixing block 3033.

[0039] As Figure 4 and Figure 5 shown, two second sliding grooves 3031 are symmetrically arranged on the outer wall of the sleeve 303. A second sliding block 3041 is respectively fixed on the side wall of each of the two second finger rings 304. The second sliding block 3041 is located in the second sliding groove 3031 and can slide along the second sliding groove 3031. The two ends of the second sliding groove 3031 are respectively an open end and a closed end, and the second sliding block 3041 slides from the open end of the second sliding groove 3031 to the closed end.

[0040] Two arc-shaped plates 307 are symmetrically fixed on the outer wall of the sleeve 303. The arc-shaped plates 307 are located at one end of the second sliding groove 3031. When the second finger ring 304 slides to the closed end of the second sliding groove 3031, the outer wall of the second finger ring 304 just fits against the inner wall of the arc-shaped plate 307.

[0041] A first limiting hole 3071 is arranged on the arc-shaped plate 307, and a second limiting hole is arranged on the side wall of the second finger ring 304. Threaded grooves are respectively arranged on the inner walls of the first limiting hole 3071 and the second limiting hole. After the second finger ring 304 is installed in place, a limiting bolt 308 is passed through the first limiting hole 3071 and connected to the second limiting hole to fix the second finger ring 304.

[0042] The first finger ring 3011 is directly connected to the handle rod 301 by bolts. When replacing the first finger ring 3011, simply unscrew the bolts. During manufacturing, various finger rings with the same outer diameter but different inner diameters are designed, and the operator can select a finger ring with a different inner diameter according to the thickness of their fingers and install it on the sleeve 303 and the handle rod 301.

[0043] In this embodiment, the first finger ring 3011 and the second finger ring 304 are detachable and can be replaced according to the thickness of the operator's fingers or personal habits, enabling the doctor's fingers to fit better with the handle, providing better gripping force, allowing the doctor to hold the handle more firmly during the surgical operation, reducing the risk of the surgical instrument slipping, and ensuring the stability of the surgical operation.

[0044] The fusing snare provided by the present invention has the following advantages:

[0045] First, in terms of technology: When the shrinkage coil of this fusing snare reaches the ideal position, it can be loosened at any time, reducing the damage to the coronary artery and its collateral circulation during the externalization of the guide wire in the guiding catheter in the reverse technique for coronary artery occlusion lesions; during transcatheter aortic valve replacement, after pulling the front end of the aortic valve delivery system over the aortic arch, the conductive protrusion is melted to reduce the problem of aortic arch injury caused by incomplete loosening and repeated pulling of the snare during the withdrawal of the shrinkage coil.

[0046] Second, in terms of economy: When using the fusing snare in the guiding catheter for chronic coronary artery occlusion lesions, if the guide wire can be loosened, unnecessary externalization of the guide wire can be reduced, thereby reducing the use of related instruments such as RG3 guide wires, and reducing the economic pressure on patients while implementing the high-cost technology of opening occluded coronary vessels.

[0047] Finally, it should be noted that: The above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements for some or all of the technical features; and these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A fusible snare, characterized in that, It includes a shrinking coil (1), a guiding catheter (2) and a handle assembly (3). The shrinking coil (1) includes an annular structure (101). One end of the annular structure (101) is provided with a conductive protrusion (102) protruding outward, and the other end of the annular structure (101) is provided with two parallel guide wires (103); a first insulating tube (104) is wrapped on the outer peripheral wall of the annular structure (101) except the conductive protrusion (102), and a second insulating tube (105) is wrapped on the outer peripheral walls of the two guide wires (103); the ends of the two guide wires (103) far away from the annular structure (101) pass through the guiding catheter (2) and are connected to the handle assembly (3).

2. The fusing snare according to claim 1, characterized in that, The annular structure (101), the conductive protrusion (102) and the two guide wires (103) are of an integrally formed structure.

3. The fusing snare according to claim 1, characterized in that, The two guide wires (103) are wrapped inside a second insulating tube (105); the second insulating tube (105) is connected to the first insulating tube (104), and the materials of the first insulating tube (104) and the second insulating tube (105) are both polytetrafluoroethylene.

4. The fusing snare according to claim 1, characterized in that, The material of the shrinking coil (1) is cobalt-chromium alloy.

5. The fusing snare according to claim 1, characterized in that, Anti-slip lines are provided on the outer peripheral wall of the first insulating tube (104).

6. The fusing snare according to claim 1, wherein, The handle assembly (3) includes a handle rod (301). A sleeve (303) is slidably connected to the handle rod (301). A second finger ring (304) is detachably connected to the sleeve (303). A fixing block (3033) is arranged inside the sleeve (303). The fixing block (3033) is located inside the handle rod (301) and is connected to the guide wire (103).

7. The fusing snare according to claim 6, wherein Two arc-shaped plates (307) are symmetrically arranged at one end of the sleeve (303) far away from the guiding catheter (2). A first limiting hole (3071) is provided on the arc-shaped plate (307), and a second limiting hole is provided on the second finger ring (304). A limiting bolt (308) passes through the first limiting hole (3071) and is threadedly connected to the second limiting hole.

8. The fusing snare according to claim 6, wherein A second sliding groove (3031) is provided on the outer peripheral wall of the sleeve (303), and a second sliding block (3041) is provided on the side wall of the second finger ring (304). The second sliding block (3041) is located in the second sliding groove (3031).

9. The fusing snare according to claim 6, characterized in that, Scale lines (306) are provided on the outer peripheral wall of the handle rod (301).

10. The fusing snare according to claim 6, wherein, A cable connector (305) is provided on the side wall of the sleeve (303), and the cable connector (305) is connected to the guide wire (103).

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