CN115300768A

CN115300768A - Catheter with releasable tip

Info

Publication number: CN115300768A
Application number: CN202211000461.XA
Authority: CN
Inventors: 吴重草; 翟梦林; 刘振全; 孙冰; 贾晶
Original assignee: Shanghai Warm Sun Medical Instrument Co ltd
Current assignee: Shanghai Warm Sun Medical Instrument Co ltd
Priority date: 2022-08-19
Filing date: 2022-08-19
Publication date: 2022-11-08
Also published as: CN115645722A; CN115634361A; CN115869520A; CN115887880A; CN115845233A

Abstract

The invention discloses a catheter with a releasable head end, which comprises the releasable head end, a catheter and a pushing structure, wherein the catheter is provided with a tube inner cavity arranged along the axial direction of the catheter; but the head end endwise slip of releasing is located in the distal end of pipe inner chamber, the head end of releasing is including arranging in all the time the release head near-end of pipe inner chamber and can by the release head distal end that the pipe inner chamber distal end extends, but the axial slip of propelling movement structure is located in the pipe, just the propelling movement structure distal end with the conflict cooperation of the release head near-end of head end of releasing, the propelling movement structure proximal end by the pipe inner chamber near-end extends, the release head distal end is elastic construction and has radial expansion performance, the external diameter is greater than behind the radial expansion of release head distal end the pipe diameter. The invention has small use limit, has larger caliber of the catheter and less invasion of the catheter cavity, and can realize larger thrombus absorption efficiency.

Description

Catheter with releasable tip

Technical Field

The present invention relates to the technical field of medical devices, in particular catheters with a releasable tip.

Background

At present, common mechanical thrombus extraction auxiliary devices comprise a thrombus extraction support and a suction catheter, and the common suction catheter is matched with a suction pump and a connecting pipe for reperfusion after thrombus extraction of the support or drug thrombolysis, or directly pumps the suction catheter to directly apply mechanical suction force to the reperfusion catheter for thrombus suction by using a direct back-suction first-pass technology (ADAPT). To achieve as complete an embolus retrieval as possible, the vessel is completely interrupted, and higher aspiration efficiency is achieved with a catheter having a larger caliber and lumen.

Patent publication No. CN107205751B discloses a thrombectomy device, which comprises a delivery catheter, a self-expandable funnel and a suction funnel catheter. The device can suck the thrombus from a position very close to the thrombus by a larger mouth part, can occlude the artery, stop flowing and suck the whole thrombus without breaking the thrombus; however, the double conduit structure will sacrifice the inner diameter of the suction conduit to some extent and lose the suction efficiency.

The invention patent of application publication No. CN111867495A discloses a clot removal device comprising an expandable treatment member and a delivery wire, which can also be used to capture emboli during ischemic treatment, but which does not have a safe release/retrieval to ensure that it is released in the correct location in the vessel.

Disclosure of Invention

The invention aims to solve the problems in the prior art and provides a catheter with a releasable head end, which can realize higher thrombus absorption efficiency.

In order to achieve the above object, the present invention provides a catheter with a releasable tip, comprising a releasable tip, a catheter and a pushing structure, the catheter having a tube lumen disposed along an axial direction thereof; but the head end endwise slip of releasing is located in the distal end of pipe inner chamber, the head end of releasing is including arranging in all the time the release head near-end of pipe inner chamber and can by the release head distal end that the pipe inner chamber distal end extends, but the axial slip of propelling movement structure is located in the pipe, just the propelling movement structure distal end with the conflict cooperation of the release head near-end of head end of releasing, the propelling movement structure proximal end by the pipe inner chamber near-end extends, the release head distal end is elastic construction and has radial expansion performance, the external diameter is greater than behind the radial expansion of release head distal end the pipe diameter.

Preferably, the distal end of the catheter is provided with a stepped hole section with a diameter larger than that of the inner cavity of the tube, the proximal end of the release head is slidably connected with the stepped hole section, and the length of the stepped hole section is larger than or equal to that of the delivery state of the release head.

Preferably, the distal end of the catheter and the distal and/or proximal ends of the releasable tip are provided with visualization elements.

Preferably, the outer wall of the proximal end of the release head is provided with at least three convex points attached to the inner cavity of the tube or a convex ring protruding outwards.

Preferably, the far end of the tube inner cavity is provided with a closing-up limiting part, the diameter of which is smaller than the outer diameter of the convex ring so as to prevent the near end of the release head from separating from the far end of the tube inner cavity.

Preferably, the inner wall of the far end of the inner cavity of the tube is provided with a plurality of sliding chutes in sliding fit with the salient points, and two ends of each sliding chute are sealed

Preferably, the outer surface of the proximal end of the release head is provided with a first friction surface, and the opening of the distal end of the inner cavity of the tube is provided with a second friction surface which is matched with the first friction surface to prevent the proximal end of the release head from being separated from the inner cavity of the tube.

Preferably, the proximal end of the releasable tip has a tendency to gradually expand outward from the distal end to the proximal end, and the maximum outer diameter of the proximal end of the releasable tip in a free state is larger than the inner diameter of the distal port of the lumen of the tube to prevent the proximal end of the releasable tip from being detached from the catheter.

Preferably, the pushing structure comprises a pushing rod slidably arranged in the conduit and a supporting block fixedly arranged at the far end of the pushing rod, and the supporting block is in interference fit with the releasable head end.

Preferably, the pushing structure further comprises a pull wire arranged in the catheter, the distal end of the pull wire is fixedly connected with the proximal end of the release head, and the proximal end of the pull wire extends out of the proximal end of the catheter.

Preferably, the pushing structure is slidably arranged in the inner cavity of the catheter or a push rod sliding hole matched with the pushing structure is arranged on the inner wall of the catheter.

Preferably, the distal end of the release head is of a braided structure, and is in a claw shape, a barrel shape, a funnel shape or a bell shape after being radially expanded.

Preferably, the distal end port of the catheter is provided with a resilient structure which is an interference fit with the distal end of the release head upon aspiration.

The catheter with the releasable head end has the beneficial effects that: the releasable head end is slidably arranged at the far end of the inner cavity of the tube, so that the releasable head end is not required to be conveyed through another pipeline, the use is more convenient, the conveying, releasing and recovering of the releasable head end can be realized through a single catheter, the use limit is small, the catheter cavity is less invaded while the diameter is larger, and the larger thrombus absorbing efficiency can be realized.

The features and advantages of the present invention will be described in detail by embodiments in conjunction with the accompanying drawings.

Drawings

Fig. 1 is a schematic view of a delivery state of a releasable tip of a catheter embodiment of the present invention having a releasable tip.

Fig. 2 is a schematic view of a releasable tip release configuration of an embodiment of a catheter having a releasable tip according to the present invention.

Fig. 3 is a schematic view of the cross-sectional structure B-B in fig. 1.

FIG. 4 is a schematic view of the internal structure of a second catheter according to an embodiment of the present invention.

FIG. 5 is a schematic view of a catheter having a releasable tip according to an embodiment of the present invention in a released state.

FIG. 6 is a schematic view of the third structure of the embodiment shown in section B-B of FIG. 1.

Fig. 7 is a schematic structural diagram of a release state of the releasable head according to the third embodiment.

Fig. 8 is a schematic view of a fourth embodiment of a catheter having a releasable tip according to the present invention.

Fig. 9 is a schematic diagram of a fifth embodiment of a catheter of the present invention having a releasable tip.

Fig. 10 isbase:Sub>A schematic view of the cross-sectional structurebase:Sub>A-base:Sub>A in fig. 1.

Fig. 11 is a schematic diagram of a fifth embodiment of a catheter of the present invention having a releasable tip.

Wherein: 1-a releasable head; 2-a catheter; 3-a pushing structure; 101-a release head distal end; 102-proximal release head; 13-bumps; 111-a slide rail; 112-a chute; 21-a stepped bore section; 211-a closing-in limiting part; 212-a second friction face; 301-a subtraction block; 302-a push rod; 303-drawing wires; 1011-first friction face.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is further described in detail below with reference to the accompanying drawings and examples. It should be understood, however, that the description herein of specific embodiments is only intended to illustrate the invention and not to limit the scope of the invention. Moreover, in the following description, descriptions of well-known structures and techniques are omitted so as to not unnecessarily obscure the concepts of the present invention.

In the description of the present invention, it should be noted that when an element is referred to as being "fixed" or "disposed" to another element, it can be directly on the other element or be indirectly on the other element. When an element is referred to as being "connected to" another element, it can be directly connected to the other element or be indirectly connected to the other element.

In the description of the present invention, it should be noted that the terms "center", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc. indicate orientations or positional relationships based on orientations or positional relationships shown in the drawings, or orientations or positional relationships that are conventionally placed when the product of the present invention is used, and are merely for convenience of description and simplification of the description, but do not indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore should not be construed as limiting the present invention. Furthermore, the terms "first," "second," "third," and the like are used solely to distinguish one from another and are not to be construed as indicating or implying relative importance. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of the present invention, "a plurality" means two or more unless specifically defined otherwise. The meaning of "a number" is one or more unless specifically limited otherwise.

In the description of the present invention, it should also be noted that, unless otherwise explicitly specified or limited, the terms "disposed," "mounted," "connected," and "connected" are to be construed broadly and may, for example, be fixedly connected, detachably connected, or integrally connected; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meanings of the above terms in the present invention can be understood in specific cases to those skilled in the art.

The first embodiment is as follows:

referring to fig. 1 and 2, the catheter with a releasable tip according to the present invention includes a releasable tip 1, a catheter 2 and a pushing structure 3, wherein the catheter 2 has a tube inner cavity disposed along an axial direction thereof; the releasable head end 1 is axially slidably arranged in the far end of the inner cavity of the tube, the releasable head end 1 comprises a proximal release head end 102 which is always arranged in the inner cavity of the tube and a distal release head end 101 which can extend out from the distal end of the inner cavity of the tube, the pushing structure 3 is axially slidably arranged in the catheter 2, the far end of the pushing structure 3 is in interference fit with the proximal release head end 102 of the releasable head end 1, the distal release head end 101 is of an elastic structure and has radial expansion performance, and the outer diameter of the distal release head end 101 after radial expansion is larger than the diameter of the catheter 2. In this embodiment, through can release head end 1 slidable setting at the distal end of pipe cavity, need not to release head end 1 through other pipe transmission, it is more convenient to use, single pipe 2 can realize can release the transport and release, the recovery of head end 1, the restriction is little in use, less encroach on pipe cavity way when having great bore, can realize great inhale and tie efficiency, this application is under the delivery state, can release head end 1 and accomodate the distal end at the pipe cavity, when delivering to suitable position, can release head end 1 to the propelling movement of distal end direction through propelling movement structure 3, release head distal end 101 and release outside the pipe cavity until, release head proximal end 102 is injectd in the distal end of pipe cavity, release head distal end 101 radially expand from expanding or prop open through supplementary such as traction/sacculus. Therefore, thrombus can be sucked by directly matching the inner cavity of the tube with the releasable head end 1, various auxiliary thrombus taking equipment can be guided into the inner cavity of the tube, and the distal end 101 of the releasable head can prevent thrombus from escaping.

Referring to fig. 1 and 2, the distal end of the tube lumen is provided with a stepped bore section 21 having a larger diameter than the tube lumen, the proximal release head end 102 is slidably connected to the stepped bore section 21, and the length of the stepped bore section 21 is longer than the length of the releasable head end 1 in the delivery state. Set up step hole section 21 and be convenient for with can release head end 1 cooperation, can release head end 1 shrink and can accomodate completely at step hole section 21 when the pipe cavity, avoid can releasing head end 1 and encroach on the pipe cavity space, maximize suction efficiency.

Referring to fig. 1 and 2, the distal end of catheter 2 and the distal and proximal ends of releasable tip 1 are provided with visualization elements. The relative position of the releasable head end 1 and the opening at the far end of the catheter 2 can be positioned by the developing element, so that the release head end 1 is prevented from being excessively pushed to cause falling off.

The second embodiment:

referring to fig. 3 and 4, on the basis of the first embodiment, the outer wall of the proximal end 102 of the release head is provided with four protrusions 13 which are attached to the inner cavity of the tube. The proximal end 102 of the release head can be tightly attached to the inner wall of the inner cavity of the tube, so that the stability is improved and the release head is prevented from falling off.

Referring to fig. 3 and 4, the inner wall of the distal end of the tube cavity is provided with a plurality of sliding grooves 112 which are in sliding fit with the salient points 13. The sliding groove 112 is closed at both ends. The convex points 13 are matched with the sliding grooves 112 with two closed ends to limit the proximal end 102 of the release head, so that the proximal end 102 of the release head is prevented from being separated from the far end of the inner cavity of the tube, and the safety is improved.

Example three:

referring to fig. 5, 6 and 7, in the first embodiment, the outer wall of the proximal end 102 of the release head is provided with a convex ring 14 protruding outwards. The distal end of the stepped bore section 21 is provided with a stop mechanism closing-in stop 211 having a diameter smaller than the diameter of the proximal release head end 102 to prevent the proximal release head end 102 from disengaging the stepped bore section 21. The closing-up limit portion 211 of the limit mechanism can be matched with the outer ring of the proximal end 102 of the release head to limit the proximal end 102 of the release head in the stepped hole section 21, so as to prevent the releasable head end 1 from being separated from the catheter 2.

Example four:

referring to fig. 8, the outer surface of the proximal end 102 of the release head is provided with a first friction surface 1011 formed by coating, heat melting and surface treatment, and the distal opening of the lumen of the tube is provided with a second friction surface 212 for cooperating with the first friction surface 1011 to prevent the proximal end 102 of the release head from separating from the lumen of the tube. By the frictional engagement of the first friction surface 1011 and the second friction surface 212, a larger frictional force can be generated, thereby limiting the release head proximal end 102 to the distal end of the tube lumen and preventing the release head proximal end 102 from disengaging.

Example five:

referring to fig. 9, the proximal releasable end 102 has a tendency to expand gradually from the distal end to the proximal end, and the maximum outer diameter of the proximal releasable end 102 in the free state is larger than the inner diameter of the distal port of the catheter 2, so that the proximal releasable end 102 can be tightly attached to the inner wall of the catheter 2 when inside the catheter 2 to prevent the proximal releasable end 102 from being detached from the catheter 2.

Example six:

referring to fig. 10 and 11, the pushing structure 3 includes a pushing rod 302 slidably disposed in the conduit 2 and a pressing block 301 fixedly disposed at a distal end of the pushing rod 302, the pressing block 301 is in abutting engagement with the releasable head end 1, and a cross section of the pushing rod 302 is a circular ring shape coaxially disposed with the conduit 2. Pushing rod 302 drives abutting block 301 to move so as to cooperate with releasable head 1, pushing releasable head 1 out of catheter 2. In this embodiment, the section of the pushing rod 302 is a circular ring shape coaxially arranged with the catheter 2, that is, the pushing structure 3 is also a hollow tube shape inside, this arrangement mode is convenient for conveying other instruments through the inside of the pushing structure 3, the normal use of the catheter 2 is not affected, and the pushing structure 3 can be immediately withdrawn after pushing is completed. In another alternative embodiment, the pushing structure 3 may have a semi-annular cross section coaxially arranged with the catheter 2, and may be a plurality of pushing structures 3.

Referring to fig. 11, the pushing structure 3 further includes a pulling wire 303 disposed inside the catheter 2, wherein a distal end of the pulling wire 303 is fixedly connected to the proximal end 102 of the releasing head, and a proximal end thereof extends out of the proximal end of the catheter 2. When the releasable head end 1 is in a release state and needs to be retracted, the releasable head end 1 can be pulled by the traction wire 303 to retract until the releasable head end 1 retracts into the inner cavity of the pipe, so that the releasable head end 1 can be retracted conveniently.

Preferably, the pushing structure 3 is slidably disposed within the lumen. The direct slidable setting of propelling movement structure 3 in this embodiment is at the lumen, is convenient for take out propelling movement structure 3, avoids propelling movement structure 3 to influence the suction. In another alternative embodiment, the inner wall of the catheter 2 may also be provided with a push rod sliding hole adapted to the pushing structure 3, and the pushing structure 3 may be slidably disposed in the push rod sliding hole, in which the push rod sliding hole and the inner cavity of the catheter are separately disposed to avoid mutual interference.

Preferably, the distal release head end 101 is of a braided construction, and the distal release head end 101 is formed into a claw, cylinder, funnel, or bell shape after radial expansion.

Preferably, the releasable tip 1 comprises an impermeable membrane made of a biocompatible elastomeric polymer.

Preferably, the proximal release head end 102 is in the form of a constriction or other cylindrical configuration or other material constriction of the same structure as the distal release head end 101.

Preferably, the distal end port of the catheter 2 is provided with an elastic structure, for example, the distal end port of the catheter 2 is coated with silica gel, and in a suction state, the distal end 101 of the release head is tightly attached to the distal end port of the catheter 2 under the effect of blood flow, and the elastic structure enables the distal end 101 of the release head to be in interference fit with the distal end port of the catheter 2, so as to further avoid leakage in a suction process.

The working process of the invention is as follows:

in the working process of the catheter with the releasable head end, the releasable head end 1 is stored at the far end of the inner cavity of a tube in a delivery state, the catheter 2 is delivered along the blood vessel, when the catheter is delivered to a thrombus position, the releasable head end 1 is pushed towards the far end direction through the pushing structure 3 until the far end 101 of the release head is released out of the inner cavity of the tube, the near end 102 of the release head is limited at the far end of the inner cavity of the tube, the far end 101 of the release head radially expands and expands or is supported by traction/balloon and the like, the far end 101 of the release head can be attached to the inner wall of the blood vessel after expanding, therefore, thrombus can be sucked and prevented from escaping through the inner cavity of the tube in a matching way with the releasable head end 1, and various devices for assisting thrombus taking can be introduced into the inner cavity of the tube.

The above embodiments are illustrative of the present invention, and are not intended to limit the present invention, and any simple modifications of the present invention are within the scope of the present invention.

Claims

1. A catheter with a releasable tip comprising a releasable tip (1), a catheter (2) and a pushing structure (3), characterized in that: the catheter (2) is provided with a tube inner cavity arranged along the axial direction of the catheter; but what release head (1) slidable axial was located in the distal end of tube cavity, but release head (1) is including arranging in all the time release head near-end (102) of tube cavity and can by release head distal end (101) that the tube cavity distal end extends, but push structure (3) slidable axial is located in pipe (2), just push structure (3) distal end with release head near-end (102) of release head (1) conflict the cooperation, push structure (3) near-end by the tube cavity near-end extends, release head distal end (101) are elastic structure and have the radial expansion performance, the external diameter is greater than behind release head distal end (101) the radial expansion pipe (2) diameter.

2. A catheter having a releasable tip as in claim 1, wherein: the far end of the catheter (2) is provided with a step hole section (21) with the diameter larger than that of the inner cavity of the catheter, the near end (102) of the release head is connected with the step hole section (21) in a sliding mode, and the length of the step hole section (21) is larger than or equal to that of the delivery state of the releasable head end (1).

3. A catheter having a releasable tip as in claim 1, wherein: the distal end of the catheter (2) and the distal and/or proximal end of the releasable tip (1) are provided with visualization elements.

4. A catheter having a releasable tip as in claim 1, wherein: the outer wall of the proximal end (102) of the release head is provided with at least three salient points (13) attached to the inner cavity of the tube or the outer wall of the proximal end (102) of the release head is provided with a convex ring (14) protruding outwards.

5. A catheter having a releasable tip as in claim 4, wherein: the far end of the tube inner cavity is provided with a closing-up limiting part (211) with the diameter smaller than the outer diameter of the convex ring (14) so as to prevent the near end (102) of the release head from separating from the far end of the tube inner cavity.

6. A catheter having a releasable tip according to claim 4, wherein: the inner wall of the far end of the inner cavity of the tube is provided with a plurality of sliding grooves (112) which are in sliding fit with the salient points (13), and two ends of each sliding groove (112) are arranged in a sealed mode.

7. A catheter having a releasable tip as in claim 1, wherein: the outer surface of the proximal end (102) of the release head is provided with a first friction surface (1011), and the opening at the distal end of the inner cavity of the tube is provided with a second friction surface (212) which is used for being matched with the first friction surface (1011) to prevent the proximal end (102) of the release head from being separated from the inner cavity of the tube.

8. A catheter having a releasable tip as in claim 1, wherein: the proximal releasable end (102) has a tendency to gradually expand outward from the distal end to the proximal end, and the maximum outer diameter of the proximal releasable end (102) in a free state is larger than the inner diameter of the lumen distal port to prevent the proximal releasable end (102) from being detached from the catheter (2).

9. A catheter having a releasable tip as in claim 1, wherein: the pushing structure (3) comprises a pushing rod (302) which is slidably arranged in the catheter (2) and a supporting block (301) which is fixedly arranged at the far end of the pushing rod (302), and the supporting block (301) is in interference fit with the releasable head end (1).

10. A catheter having a releasable tip as in claim 9, wherein: the pushing structure (3) further comprises a traction wire (303) arranged in the catheter (2), the far end of the traction wire (303) is fixedly connected with the near end (102) of the release head, and the near end extends out of the near end of the catheter (2).

11. A catheter having a releasable tip according to claim 1, wherein: the distal end port of the catheter (2) is provided with an elastic structure, and is in interference fit with the distal end (101) of the release head during suction.