CN110623705B

CN110623705B - Suction catheter with adjustable suction cavity opening caliber

Info

Publication number: CN110623705B
Application number: CN201910912513.2A
Authority: CN
Inventors: 李林静; 王昂; 朱国辉
Original assignee: Guangzhou Chuangjing Medical Technology Co ltd
Current assignee: Guangzhou Yijie Medical Technology Co ltd
Priority date: 2019-09-25
Filing date: 2019-09-25
Publication date: 2020-11-24
Anticipated expiration: 2039-09-25
Also published as: CN110623705A

Abstract

An aspiration catheter with an adjustable aspiration cavity opening caliber is provided, which comprises a catheter main body, an aspiration head and a control assembly, wherein the aspiration head is connected to the far end of the catheter main body, and the far end of the aspiration head forms an aspiration cavity opening; the suction head comprises a support and a covering net, the support is elastic and is in a horn mouth shape with a far-end caliber larger than a near-end caliber in a natural state, the covering net is tightened and becomes compact or loosened by loosening, the control assembly is connected with one or more silk threads forming the covering net, when the silk threads are pulled, the covering net becomes compact, the support is compressed, so that the opening of the suction cavity is contracted, when the silk threads are released, the covering net becomes loose by resilience of the support, so that the opening of the suction cavity is expanded, and the outer peripheral surface and/or the inner peripheral surface of the suction head are/is completely covered with an elastic hydrophobic film. The coated net is controlled to increase the opening caliber of the suction cavity so as to realize suction of large thrombus, and the opening caliber of the suction cavity is reduced in the withdrawing process, so that the blood vessel injury caused by friction between the suction catheter and the blood vessel wall is relieved.

Description

Suction catheter with adjustable suction cavity opening caliber

Technical Field

The present invention relates to interventional medical devices and, in particular, to an aspiration catheter device for intravascular thrombus removal.

Background

Acute ischemic stroke (acute cerebral infarction, generally within 2 weeks of onset) is the most common type of stroke, and is caused by cerebral thrombosis or cerebral tissue hypoxia caused by cerebral vessels blocked by thrombus. Cerebral thrombosis has the characteristics of high morbidity, high disability rate, high mortality rate, high recurrence rate and the like. The treatment methods mainly comprise two main categories of drug thrombolysis and mechanical thrombus removal. However, the effect of pure drug thrombolysis or mechanical thrombus removal is not ideal from the current clinical effect.

The mechanical thrombus extraction mainly comprises thrombus suction, thrombus extraction by a catcher and laser thrombus crushing. The main problem is that when the embolus is large, the thrombus is not necessarily withdrawn by simply sucking the thrombus, and the embolus can escape from the far-end embolus and block the far-end blood vessel in the withdrawing process by the catcher, so that more serious adverse reaction is caused.

The aspiration lumen opening of conventional aspiration catheters has a fixed cross-sectional area and cannot accommodate larger embolic particles. Conventional aspiration catheters have a circular or oval suction lumen opening, the circular cross-section being adapted to fully contact the clot to be aspirated and the thrombus on the straight wall, and the oval cross-section being adapted to aspirate thrombus at an angle to the catheter, but which is not adapted to fully contact the clot directly with the suction lumen opening. The above-mentioned various conventional aspiration catheters have disadvantages, respectively, and have poor aspiration effect on massive thrombi.

In addition, some aspiration catheters also have a soft balloon that is provided at the distal end portion of the outer layer and can be inflated or deflated in order to block the impact of the blood flow outside the aspiration catheter on the thrombus when aspirating the thrombus. The provision of such a soft balloon has the following disadvantages:

first, friction is increased during transport of the distal end of the aspiration catheter, resulting in a relatively far aspiration catheter that may not be able to travel in some tortuous complex lesion structures;

secondly, the soft saccule is in a contracted state in the process of withdrawing the thrombus and the suction catheter, and at the moment, the thrombus can be impacted by blood flow to cause the escape of the thrombus;

thirdly, the process of compounding the soft balloon outside the catheter is complicated, resulting in high production cost.

Therefore, it is highly desirable to solve the technical problem of providing a better thrombus extraction device that can effectively capture a larger thrombus.

Disclosure of Invention

The present invention has been made in view of the state of the art described above. The invention aims to provide an aspiration catheter with an adjustable aspiration cavity opening caliber, which can effectively capture large thrombus.

Providing an aspiration catheter with an adjustable aspiration lumen opening caliber, comprising a catheter body, an aspiration tip and a steering assembly, the aspiration tip being connected to a distal end of the catheter body, the distal end of the aspiration tip forming the aspiration lumen opening;

the suction head comprises a bracket and a coating net, the bracket has elasticity and is in a bell mouth shape with the caliber of the far end larger than that of the near end in a natural state, the coating net is tightened and compacted or loosened by being loosened,

the manipulation assembly is connected to one or more wires forming the cover mesh, the cover mesh is densified when the wires are pulled, the stent is compressed so that the suction lumen opening is contracted, and the cover mesh is loosened by a resilient force of the stent so that the suction lumen opening is expanded when the wires are released;

the outer and/or inner circumferential surfaces of the suction head are entirely covered with an elastic hydrophobic film.

In at least one embodiment, the stent is made of a memory alloy.

In at least one embodiment, the support includes a plurality of finger portions, a plurality of finger portions are in the even distribution around the axis of suction catheter, the near-end of a plurality of finger portions connect in the distal end of catheter body, the distal end dispersion of a plurality of finger portions, the cladding net is in suction catheter's radial inside and outside alternately pass between a plurality of finger portions and twine in proper order a plurality of finger portions, work as control the subassembly tractive during the silk thread, the distal end of a plurality of finger portions is gathered together, works as control the subassembly release during the silk thread, the distal end dispersion of a plurality of finger portions.

In at least one embodiment, the steering assembly is connected to the one or more wires at the distal end of the cover mesh such that the one or more wires at the distal end of the cover mesh are steered first.

In at least one embodiment, the steering assembly includes a pull wire that is a helical wire that is helically wound about the axis of the aspiration catheter, or a naturally extending wire having a distal end attached to the cover mesh and a proximal end for being steered.

In at least one embodiment, the intermediate layer of the catheter body comprises the helical wire.

In at least one embodiment, the distal end of the spiral wire is indirectly connected to the suction tip by a transition line, which is a naturally extending wire.

In at least one embodiment, the steering assembly includes a pull wire, which is a naturally extending wire that is directly connected to the cover mesh.

In at least one embodiment, the steering assembly includes an adjustment nut coupled to a proximal end of the pull wire, the pull wire being pulled or released when the adjustment nut is twisted.

In at least one embodiment, the suction catheter further comprises a locking valve for clamping or unclamping the pull wire, the pull wire being immovable relative to the catheter body when the locking valve clamps the pull wire, the pull wire being movable relative to the catheter body when the locking valve unclamps the pull wire.

In at least one embodiment, the surface of the traction wire is coated with a lubricious coating.

In at least one embodiment, the lubricious coating is made of polytetrafluoroethylene.

In at least one embodiment, the inner layer of the catheter body is made of polytetrafluoroethylene or high density polyethylene or block polyetheramide resin blend.

In at least one embodiment, the proximal end of the suction tip is integrally connected to the distal end of the catheter body by clamping, bonding or welding.

In at least one embodiment, the outer circumferential surface of the suction head is covered with a reaction film or a reaction net that applies a compressive force to the suction head and is capable of dissolving by reacting with blood, all over the circumference.

The method for sucking the thrombus by adopting the suction catheter with the adjustable opening caliber of the suction cavity in the technical scheme is also provided, the silk thread forming the coating net is pulled in the process of pushing the suction catheter to a lesion position, and the opening of the suction cavity is always in a contracted state;

releasing the wires forming the cover mesh after the suction catheter is pushed into place, whereby the suction lumen opening is opened,

after the thrombus is aspirated into the suction tip, the wires forming the cover mesh are pulled, so that the suction lumen opening is contracted.

In at least one embodiment, the diameter of the suction lumen opening is less than or equal to the diameter of the catheter body during advancement of the suction catheter to the lesion site.

In at least one embodiment, the suction catheter further comprises a locking valve, the steering assembly comprises a pull wire, a distal end of the pull wire is connected to the cover mesh, and a proximal end of the pull wire is used for being steered;

in the process of pushing the suction catheter to the lesion position, the locking valve clamps the traction wire, and the shape of the coating net is kept unchanged;

after the suction catheter is pushed into place, the locking valve releases the pull wire, which releases the wire;

after thrombus is sucked into the suction head, the pull wire pulls the wire, and the locking valve clamps the pull wire after the suction cavity opening is contracted into position.

The technical scheme at least has the following beneficial effects:

the suction catheter that this disclosure provided realizes the suction to bold thrombus through the increase suction chamber opening bore to, at the withdrawal in-process, reduce suction chamber opening bore, because the area of contact of suction catheter and blood vessel reduces, thereby alleviated the blood vessel damage that suction catheter and vascular wall friction caused.

Moreover, the opening caliber of the suction cavity is adjusted by controlling the cladding net, so that the control structure is simple and the operability is good.

The elastic hydrophobic membrane covers the stent, thereby forming a closed suction lumen between the stent and the thrombus. In addition, elastic hydrophobic membrane fine and vascular wall compliance paste under the holding power of suction head to form the blood flow and block the structure, and the bore of the big suction opening that forms behind the adherence is favorable to strengthening the suction power, has reduced the impact force of blood flow to the thrombus simultaneously, the better thrombus escape that prevents the breakage, thereby replaced traditional soft sacculus.

The technical scheme can also have the following beneficial effects:

the suction head made of the shape memory alloy can provide enough radial supporting force for the vessel wall, thereby having good adherence, being beneficial to increasing the aperture of the opening of the suction cavity and being beneficial to removing thrombus.

When the suction catheter advances in a blood vessel with a large bending degree, the spiral thread is not easy to bend and can play a good role in controlling the suction head.

After all thrombi enter the interior of the suction head, the silk threads forming the coating net are controlled by the control assembly, and the elastic hydrophobic membrane and the slightly contracted suction head form a complete coating structure of the thrombi inside together, so that the phenomenon that the thrombi escape due to blood flow impact in the process of withdrawing the suction catheter is better prevented.

Drawings

FIG. 1 is a schematic view, partially in longitudinal section, of an aspiration catheter provided in accordance with the present disclosure, showing the aspiration lumen opening open and in close proximity to the vessel wall.

FIG. 2 is a schematic view, partially in longitudinal section, of the aspiration catheter of FIG. 1 showing the aspiration lumen opening constricted after aspiration of the thrombus.

Figure 3 is a schematic view of the suction catheter of figure 1, partly in longitudinal section, showing the suction lumen opening in a collapsed state during access to a blood vessel.

Fig. 4 is a cross-sectional view of the catheter body of the aspiration catheter of fig. 1.

Description of reference numerals:

1 catheter body, 11 inner layer, 12 outer layer, 13 braid, 2 suction tip, 3Y base, 41 spiral wire, 42 adjusting nut, 5 syringe, 6a suction lumen, 6b guide wire lumen, 8 vessel wall, 9 thrombus.

Detailed Description

Exemplary embodiments of the present invention are described below with reference to the accompanying drawings. It should be understood that the detailed description is intended only to teach one skilled in the art how to practice the invention, and is not intended to be exhaustive or to limit the scope of the invention.

As shown in fig. 1 to 4, the present disclosure provides an aspiration catheter for aspirating thrombus 9, which includes a catheter main body 1, an aspiration tip 2, and a manipulation assembly. The catheter body 1 is a multi-layered structure including an inner layer 11, an intermediate layer and an outer layer 12, which are sequentially disposed outward in a radial direction, and the intermediate layer may include a plurality of layers. The proximal end of the suction tip 2 is attached to the distal end of the catheter body 1, and the distal end of the suction tip 2 forms the suction lumen opening of the suction catheter.

The radially inner space of the catheter main body 1 serves as a suction lumen 6a and a guide wire lumen 6 b. The position of the guide wire chamber 6b can be flexibly set, and in other embodiments, the guide wire chamber 6b can also be arranged on the radial outer side of the catheter main body 1 (outer layer 12).

In one embodiment provided by the present disclosure, the suction head 2 is a coated mesh that can be tightened and densified or loosened by loosening, the coated mesh being made of an elastic material, preferably a memory material. When the coated net is in a natural state, the caliber of the far end of the coated net is larger than that of the near end of the coated net, so that the coated net has a roughly horn mouth shape.

When the silk threads forming the coating net are drawn, the coating net can become compact and the far end shrinks, so that the opening of the suction cavity shrinks and the opening caliber of the suction cavity becomes small; when the wire is released, the cover net rebounds and becomes loose and the distal end opens so that the suction lumen opening opens and the suction lumen opening caliber increases.

In another embodiment provided by the present disclosure, the suction head 2 comprises a stent, which is made of an elastic material, preferably a memory material, and a covering mesh that can be tightened to become dense or loosened by being loosened. When the stent is in a natural state, the distal end caliber of the stent is larger than the proximal end caliber of the stent, so that the stent has a roughly horn mouth shape.

The stent may, for example, comprise a plurality of fingers evenly distributed about the axis of the aspiration catheter, the proximal ends of the plurality of fingers being connected and the distal ends of the plurality of fingers being spaced apart. The cover web may be passed between two fingers crosswise radially inwards and outwards and wrapped around each finger in turn. The contraction and expansion of the opening of the suction lumen is controlled by pulling or releasing the wire to control the gathering or spreading of the plurality of fingers. The cover net and the stent are matched in the above-mentioned mode, so that the forming process and the operation process of the cover net are simple, and the cover net can be uniformly pulled or released.

The coated mesh can also cover the outer or inner peripheral surface of the stent.

When the silk threads forming the wrapping net are pulled, the wrapping net can become compact and the far end is contracted, so that the support is pressed, the opening of the suction cavity is contracted, and the aperture of the opening of the suction cavity is reduced; when the silk thread is released, the bracket rebounds and the opening of the suction cavity is opened, and meanwhile, the wrapping net becomes loose under the rebounding force of the bracket, so that the opening of the suction cavity is opened, and the caliber of the opening of the suction cavity is enlarged.

The stent may have a length of 5mm to 30mm in the axial direction of the suction catheter.

The filaments may be woven using prior art weaving methods and weaving patterns to form the cover web of the various embodiments described above, which becomes dense when the filaments forming the cover web are pulled.

The memory material is, for example, a shape memory alloy. The suction head 2 (stent or coated net) made of the shape memory alloy can provide enough radial supporting force for the vessel wall 8, thereby having good adherence, being beneficial to increasing the caliber of a suction cavity and being beneficial to removing thrombus 9.

The suction head 2 may also be made of cobalt chrome or the like.

It should be understood that the elastic materials described in this disclosure include memory materials having super-elasticity.

In the process of pushing the catheter to the lesion position, the opening of the suction cavity is always in a contracted state, and the diameter of the opening of the suction cavity is smaller than or equal to that of the catheter main body 1, so that the suction catheter can conveniently pass through a tortuous blood vessel and can better reach the lesion position. (see fig. 3)

After the suction catheter has been pushed into position, the steering assembly is operated to release the wires forming the covering mesh so that the suction lumen opening, which has a diameter greater than that of the catheter body 1, opens out, at least a portion of the outer circumference of the suction tip 2 (covering mesh) clinging to the vessel wall 8. The enlarged opening of the suction cavity is beneficial to the suction of thrombus 9 (especially massive thrombus 9), and the suction head 2 is tightly attached to the blood vessel wall 8, so that the impact of the blood flow on the thrombus 9 can be reduced. (as in FIG. 1)

After the thrombus 9 is sucked into the suction head 2, the operation and control assembly pulls the silk thread, so that the opening of the suction cavity is contracted, the suction head 2 wraps the thrombus 9, and the peripheral surface of the suction head 2 is not attached to the vessel wall 8 any more.

(see fig. 2)

Different from the existing mode that need jointly use the broken bolt of multiple product then get the bolt, the suction catheter that this disclosure provided realizes the suction to bold thrombus 9 through increase suction chamber opening bore to, in the process of withdrawing, reduce suction chamber opening bore, because the area of contact of suction catheter and blood vessel reduces, thereby alleviated the suction catheter and 8 frictions of vascular wall and the vascular injury that cause. Moreover, the opening caliber of the suction cavity is adjusted by controlling the cladding net, so that the control structure is simple and the operability is good.

The diameter of the suction lumen opening in the contracted state may be 0.5mm to 2mm, and the diameter of the suction lumen opening in the expanded state may be 1mm to 10mm, preferably 2mm to 6 mm.

The suction lumen opening has a wide range of variation and can be adapted to many types of blood vessels.

The distal end of the steering assembly is connected directly or indirectly to the aforementioned wires of the suction tip 2, and the proximal end of the steering assembly is operated to provide a pulling force.

The steering assembly may steer one wire forming the cover, such as the wire at the distal end of the cover, such that the distal wire of the cover is steered first. The steering assembly achieves more robust steering of the suction lumen opening by steering the distal end of the cover web.

The control component can be connected with different numbers of threads and the threads at different positions according to different weaving methods and weaving patterns.

The steering assembly may comprise a pull wire which may be connected directly or indirectly to the above-mentioned wire of the suction head 2. The traction wire is, for example, a spiral wire 41 formed by subjecting a naturally extending wire to a spring winding process, and the spiral wire 41 is spirally wound around the axis of the suction catheter. The distal end of the spiral wire 41 is indirectly connected to the distal end of the suction tip 2 (the cover mesh) by a transition line, such as a naturally extending wire, which may be located on the inner or outer circumferential surface of the stent, and the proximal end of the spiral wire 41 is used to be manipulated.

Both the pull wire and the transition wire may be metal wires.

In other embodiments, the pull wire may also be a naturally extending wire, and the pull wire may then be attached directly to the suction head 2 (the cover web).

When the suction catheter is advanced in a blood vessel having a large degree of bending, the spiral wire 41 is not easily bent and can perform a good operation and control of the suction tip 2.

The steering assembly may also include an adjustment nut 42, the adjustment nut 42 being connected to a spring wire that is tightened or released when the adjustment nut 42 is rotated. Twisting of the coil wire 41 may be manipulated by rotating the adjustment nut 42 to thereby conveniently control the distal end of the coil wire 41 to pull or release the wire forming the coated mesh.

The proximal end of the aspiration catheter is provided with a Y-shaped base 3, and the Y-shaped base 3 is connected to an aspiration device (e.g., a syringe 5) outside the aspiration catheter. The Y-shaped base 3 comprises a main bore extending axially and communicating with the radially inner space of the inner layer 11, and a side bore, the axis of which intersects the axis of the main bore and is inclined towards the proximal outer side of the suction catheter. Side holes, to which an adjustment nut 42 may be fitted, communicate with the gap between the inner layer 11 and the outer layer 12 to constitute a lumen for delivering a traction wire such as a spiral wire 41.

The suction catheter also comprises a locking valve which is used for clamping or loosening the traction wire, when the locking valve is closed, the traction wire is clamped by the locking valve so as not to move relative to the catheter main body 1, and the coating net is shaped; when the locking valve is opened, the traction wire is released by the locking valve and can move relative to the catheter body 1, and the covering net can be manipulated to deform.

after the suction catheter is pushed in place, the locking valve releases the pull wire, the adjusting nut 42 is operated, the pull wire releases the wire, and the opening of the suction lumen is enlarged;

after the thrombus 9 is sucked into the suction head 2, the adjusting nut 42 is operated, the pull wire pulls the silk thread, the locking valve clamps the pull wire after the opening of the suction cavity is contracted in place, and the suction cavity tightly wraps the thrombus 9.

It can be seen that the locking valve ensures that the pull wire is pulled accidentally.

The outer and/or inner circumferential surface of the suction head 2 is/are entirely covered with an elastic hydrophobic film, in particular a highly elastic hydrophobic film, which may be partially bonded to the suction head 2 (holder). When the opening of the suction cavity is opened, the elastic hydrophobic membrane is also opened, the far end of the elastic hydrophobic membrane is flush with the far end of the suction head 2, the near end of the elastic hydrophobic membrane is flush with the near end of the suction head 2, and the elastic hydrophobic membrane forms a ring shape.

The elastic hydrophobic membrane covers the stent, thereby forming a closed suction lumen between the stent and the thrombus 9. In addition, elastic hydrophobic membrane is fine under the holding power of suction head 2 to paste mutually with 8 compliance of vascular wall to form the blood flow and block the structure, and the bore of the big suction opening that forms after the adherence is favorable to strengthening the suction force, reduced the impact force of blood flow to thrombus 9 simultaneously, better prevent that broken thrombus 9 from escaping, thereby replaced traditional soft sacculus.

After all the thrombus 9 enters the inside of the suction head 2, the silk threads forming the coating net are controlled by the control assembly, and the elastic hydrophobic membrane and the slightly contracted suction head 2 form a complete coating structure of the thrombus 9 inside together, so that the phenomenon that the thrombus 9 escapes due to blood flow impact in the process of withdrawing the suction catheter is better prevented.

The elastic hydrophobic membrane can be an elastic polyurethane membrane, a nylon membrane and the like with the surface subjected to hydrophobic treatment.

The outer peripheral surface of the suction head 2 may be covered with a reaction film or a reaction net over the entire circumference, the reaction net may be formed by a natural polymer yarn after modification treatment, and the reaction film may be a natural polymer film.

Human blood is a system environment of buffer salt, and the reaction film and the reaction net both react in the buffer salt system and are formed into a form of polymer salt, so that the reaction film and the reaction net are dissolved and collapsed.

The reaction membrane or the reaction net is beneficial to providing more reliable compression force to the suction head 2 so as to ensure that the opening diameter of the suction cavity is in a required contraction state, and in addition, the reaction membrane or the reaction net can automatically apply the compression force to the suction head 2 so that the suction head 2 keeps the contraction state.

The reaction film and the reaction net can be made of oxidized cellulose and derivatives thereof.

The proximal end of the suction head 2 and the distal end of the catheter main body 1 can be connected in a clamping, bonding or welding mode, so that the suction head 2 and the catheter main body 1 form an integral tubular structure, operation and use of a clinician are facilitated, and the time for taking embolus is saved.

The inner layer 11 of the catheter body 1 may be formed as a tube from PTFE (polytetrafluoroethylene) or HDPE (high density polyethylene) or PEBAX (block polyether amide resin) mixed with an additive having a low coefficient of friction, to reduce the friction to which the inner layer 11 is subjected.

The middle layer can be in a spring winding structure by using metal wires, or in a weaving structure by using the metal wires, or in a composite structure formed by firstly winding the springs and then weaving the springs. The outer layer may be of nylon elastomer (e.g. PEBAX), nylon or PU (polyurethane).

In the present embodiment, the intermediate layer includes the braid 13 woven with the metal wires and the above-described traction wires, such as the spiral wire 41. The spiral wire 41 plays a role in manipulating the wire forming the covering net, and ensures the flexibility of the suction catheter in the conveying process so as not to damage the blood vessel wall 8, and the suction catheter has good pushing performance so as to be pushed well.

The spiral wire 41 may be located radially inward or radially outward of the braid 13. The braid 13 may be integrated with the inner layer 11 or the outer layer 12.

The catheter body 1 may have a gradually decreasing stiffness from the proximal end to the distal end.

The distal end of the catheter, e.g. the suction tip 2, may be provided with a radiopaque marker, which may be a visualization ring or a visualization coil, etc. This can facilitate the physician to monitor the position of the X-ray opaque markers by means of a vessel imaging device, such as DSA (digital X-ray imaging).

The surfaces of the pushing assembly and the control assembly can be coated with a lubricating coating, and particularly, the surface of the traction wire can be coated with the lubricating coating, so that the friction resistance generated in the processes of conveying the suction catheter and controlling the expansion and contraction of the coated net is reduced, and the lubricating coating can be made of PTFE and can be a hydrophilic coating or a hydrophobic coating.

It should be understood that the above embodiments are only exemplary and are not intended to limit the present invention. Various modifications and alterations of the above-described embodiments may be made by those skilled in the art in light of the teachings of the present invention without departing from the scope thereof.

Claims

1. An aspiration catheter with adjustable aspiration lumen opening caliber, characterized in that it comprises a catheter body (1), an aspiration tip (2) and a manipulation assembly, the aspiration tip (2) is connected to the distal end of the catheter body (1), the distal end of the aspiration tip (2) forms the aspiration lumen opening;

the suction head (2) comprises a bracket and a coating net, the bracket has elasticity and is in a bell mouth shape with a far end caliber larger than a near end caliber in a natural state, the coating net is tightened and compacted or loosened by being loosened,

the outer circumferential surface and/or the inner circumferential surface of the suction head are/is completely covered with an elastic hydrophobic film;

the stent comprises a plurality of finger parts which are uniformly distributed around the axis of the suction catheter, the proximal ends of the plurality of finger parts are connected to the distal end of the catheter main body (1), the distal ends of the plurality of finger parts are dispersed, the coated net penetrates through the plurality of finger parts in a radial direction of the suction catheter in a crossed manner, the coated net is wound around the plurality of finger parts in sequence, when the control assembly pulls the silk thread, the distal ends of the plurality of finger parts are gathered, and when the control assembly releases the silk thread, the distal ends of the plurality of finger parts are dispersed;

the outer peripheral surface of the suction head (2) is covered with a reaction film or a reaction net that applies a compressive force to the suction head (2) and can react with blood to dissolve.

2. The aspiration catheter of claim 1 wherein the stent is made of a memory alloy.

3. The aspiration lumen open gauge adjustable aspiration catheter of claim 1, wherein the steering assembly is connected to the one or more wires at the distal end of the cover mesh such that the one or more wires at the distal end of the cover mesh are steered first.

4. The aspiration lumen open-gauge adjustable aspiration catheter of claim 1, wherein the steering assembly comprises a pull wire, the pull wire being a spiral wire (41), the spiral wire (41) being helically wound around the axis of the aspiration catheter, or the pull wire being a naturally extending wire, the distal end of the pull wire being attached to the cover mesh and the proximal end of the pull wire being adapted to be steered.

5. The aspiration catheter with adjustable aspiration lumen open caliber of claim 4, wherein the middle layer of the catheter body (1) comprises the spiral wire (41).

6. The aspiration catheter with adjustable aspiration lumen open gauge of claim 4 wherein the distal end of the spiral wire (41) is indirectly connected to the aspiration tip (2) by a transition line, which is a naturally extending wire.

7. The aspiration lumen open caliber adjustable aspiration catheter of claim 1, wherein the steering assembly comprises a pull wire, the pull wire being a naturally extending wire, the pull wire being directly connected to the covering mesh.

8. The suction lumen open caliber adjustable suction catheter of claim 4, wherein the steering assembly includes an adjustment nut (42), the adjustment nut (42) being coupled to a proximal end of the pull wire, the pull wire being pulled or released when the adjustment nut (42) is twisted.

9. The aspiration lumen open-gauge adjustable aspiration catheter of claim 4, further comprising a locking valve for clamping or unclamping the pull wire, wherein the pull wire is not movable relative to the catheter body (1) when the locking valve clamps the pull wire, and wherein the pull wire is movable relative to the catheter body (1) when the locking valve unclamps the pull wire.

10. The suction lumen open-gauge adjustable suction catheter of claim 4, wherein the surface of the pull wire is coated with a lubricious coating.

11. The aspiration catheter of claim 10 wherein the lubricious coating comprises polytetrafluoroethylene.

12. The aspiration catheter with adjustable aspiration lumen opening diameter according to claim 1, wherein the inner layer (11) of the catheter body (1) is made of polytetrafluoroethylene or high density polyethylene or polyether block amide resin mixed.

13. The suction lumen open-gauge adjustable suction catheter as claimed in claim 1, wherein the proximal end of the suction tip (2) is integrally connected to the distal end of the catheter body (1) by clamping, bonding or welding.