CN110353762B

CN110353762B - Thrombus taking device

Info

Publication number: CN110353762B
Application number: CN201910533532.4A
Authority: CN
Inventors: 周振华
Original assignee: First Affiliated Hospital of PLA Military Medical University
Current assignee: First Affiliated Hospital of PLA Military Medical University
Priority date: 2019-06-19
Filing date: 2019-06-19
Publication date: 2020-08-21
Anticipated expiration: 2039-06-19
Also published as: CN110353762A

Abstract

The invention relates to the technical field of medical instruments, in particular to a thrombus removal device; the micro catheter is used for conveying the thrombus taking support, the guiding device is used for pushing and pulling the thrombus taking support, and the thrombus taking support comprises a plurality of metal wires and metal caps; the metal wires are mutually wound to form an internal cavity, the surface of the metal wires is a cylindrical net-shaped structure, the net-shaped structure is propped open and then attached to the inner wall of the blood vessel, one end of the net-shaped structure is gathered by the metal wires to form a gathering end, the other end of the net-shaped structure is dispersed by the metal wires to form an open end, and the gathering end is fixedly connected with the guiding device; the metal cap is of an umbrella-shaped structure, the metal cap is fixedly connected with the open end, and the open end of the metal cap surrounds the net-shaped structure. The invention aims to solve the problems that thrombus cannot be completely taken out through mechanical tethering in the tethering process of a patient, and secondary embolism is easily caused by thrombus falling off.

Description

Thrombus taking device

Technical Field

The invention relates to the technical field of medical instruments, in particular to a thrombus removal device.

Background

The intracranial thrombus has the characteristics of high morbidity, high disability rate, high death rate and high recurrence rate, and is a main disease causing death and disability of the middle-aged and the elderly. With the increasing population and living standard of the elderly, the incidence of intracranial thrombosis is increasing.

Current conventional methods for treating intracranial intravascular thrombosis include two broad categories: intravascular thrombolysis and mechanical embolectomy. The intravascular thrombolysis is formed by injecting the thrombolysis agent near a lesion in a blood vessel with a duct, so that high thrombolysis concentration is formed in the local part of the lesion instantly, the thrombolysis speed is accelerated, and the opportunity of recanalization of the blood vessel is increased. However, intravascular thrombolytic therapy is only suitable for small-volume thrombi, and the therapeutic effect on large-volume thrombi is not ideal. The mechanical thrombus extraction is to convey the thrombus extractor to a lesion position and then extract the thrombus out of the body through a sheath tube.

However, the radial supporting force of the existing mechanical embolectomy device is reduced along with the increase of the diameter, and because the diameter of the proximal blood vessel is larger than that of the distal blood vessel, the reduction of the supporting force is not enough to capture thrombus during the process of withdrawing the stent from the distal end to the proximal end, so that the thrombus falls off to cause secondary embolism.

Disclosure of Invention

Aiming at the defects in the prior art, the invention provides a thrombus removal device, which aims to solve the problems that thrombus cannot be completely removed through mechanical thrombus removal in the thrombus removal process of a patient, and secondary embolism is easily caused due to thrombus falling off.

In order to achieve the purpose, the invention adopts the following technical scheme: a thrombus removal device comprises a guiding device, a micro catheter and a thrombus removal support, wherein the micro catheter is used for conveying the thrombus removal support, the guiding device is used for pushing and pulling the thrombus removal support, the thrombus removal support comprises a metal cap and a plurality of metal wires, and the metal wires and the metal cap are both made of shape memory alloy; the metal wires are mutually wound to form an internal cavity, the surface of the metal wire is of a cylindrical net structure, one end of the net structure is gathered by the metal wires to form a gathering end, the other end of the net structure is dispersed by the metal wires to form an open end, and the gathering end is fixedly connected with the guiding device; the metal cap is of an umbrella-shaped structure, the metal cap is fixedly connected with the open end, and the open end of the metal cap surrounds the net-shaped structure.

When the technical scheme is adopted, after the micro catheter reaches the part of the patient needing to take out the thrombus, the guiding device is pushed, the thrombus taking support enters the pipeline of the micro catheter, and at the moment, the plurality of metal wires and the metal caps are in a contraction state in the micro catheter; when the metal cap reaches the opening of the microcatheter, the pushing of the guiding device is stopped, the microcatheter is retracted, the metal wires and the metal cap are exposed in the blood vessel and gradually opened, so that the metal wires and the metal cap are in a release state, and a net structure formed by the metal wires is attached to the inner wall of the blood vessel to capture thrombus, so that the thrombus enters the cavity. And pulling back the guiding device to enable the thrombus to be pulled back into the microcatheter along with the plurality of metal wires, when the capturing force of the plurality of metal wires on the thrombus is insufficient, the thrombus slides to the open end from the cavity, and the thrombus at the open end is intercepted by the metal cap, so that the thrombus is taken out along with the withdrawn thrombus taking support. Therefore, the problem that the thrombus falls off from the metal wire when the thrombus is taken, so that the thrombus cannot be taken cleanly and secondary thrombus is caused is solved.

Further, the embolectomy support also comprises a metal piece, a developing wire and a metal tube, and the guide device comprises a guide piece and a kit; the top of the metal cap is provided with a mounting hole; the metal pipe is positioned in the cavity, the outer surface of one end of the metal pipe is fixedly connected with the polymerization end, and the other end of the metal pipe is fixedly arranged in the mounting hole; the metal piece comprises a metal sleeve and a torsion spring; the metal sleeve covers the outer surface of the metal cap, and the middle part of the metal sleeve extends into the mounting hole and is connected with one end of the torsion spring; the other end of the torsion spring is fixedly connected with the metal tube, and the part of the metal sleeve, which is positioned in the metal tube, of the torsion spring is wound on the outer surface of the torsion spring in a natural state; the guide piece is fixedly connected with the polymerization end, inserted in the sleeve and connected with the sleeve in a sliding manner; and two ends of the developing wire are respectively fixedly connected with the metal sleeve and the sleeve.

After the thrombus is captured by the metal wire and enters the cavity, the sleeve piece is pulled firstly, the sleeve piece drives the developing wire to slide outwards relative to the guide piece, so that the developing wire drives the metal sleeve to move from the open end to the polymerization end, the torsion spring rotates to store force, the metal sleeve on the torsion spring is gradually pulled out until the metal sleeve reaches the polymerization end, and the metal sleeve wraps the outer surface of the metal wire. Thereby avoided the thrombus of catching to drop from the mesh that forms between the wire, simultaneously, the volume of the metal covering on the torsion spring reduces for the pipeline of tubular metal resonator is unblocked, and blood can enter into the pipeline of tubular metal resonator from the mounting hole and flow to in the blood vessel of thrombus below, thereby has avoided when getting the thrombus blood in the blood vessel to be stopped up.

Further, the net structure has at least two kinds of meshes having different areas.

Different meshes are not only favorable for thrombus of different sizes to enter from the meshes, but also prevent thrombus which just enters the cavity from easily sliding out of the cavity when being pulled through the meshes of different sizes.

Furthermore, a plurality of through holes are arranged on the cap body of the metal cap at intervals, a plurality of round holes are sleeved on the metal sleeve, and the round holes correspond to the through holes one to one when the other end of the metal sleeve is pulled to the polymerization end state.

Blood in the blood vessel passes through the round hole and the through hole and can flow out of the thrombus taking support or enter the thrombus taking support, so that the thrombus taking support is prevented from blocking the blood vessel, and the blood is not smooth.

Further, the outer surfaces of the metal cap and the metal sleeve are coated with lubricating coatings.

The lubricating coating is applied to avoid the damage of the metal cap and the technical sleeve to the blood vessel in the pulling process.

The beneficial effect that this scheme produced is: 1. through the fixed installation metal cap in the open end of wire, when the trapping force of a plurality of wires to the thrombus was not enough, the thrombus was followed the cavity and is slided to open end department and is intercepted by the metal cap to avoid droing of thrombus, make the thrombus draw back to in the little pipe along with a plurality of wires together. The thrombus can be completely taken out by the thrombus taking device in the thrombus taking process, and the thrombus is not easy to fall off in the thrombus taking process.

2. After the thrombus is captured by the metal wire, the developing wire is pulled through the sleeve piece, the metal sleeve on the torsion spring is gradually pulled out, the metal sleeve moves from the open end to the polymerization end, and when the metal sleeve reaches the polymerization end, the metal sleeve wraps the outer surface of the metal wire, so that the captured thrombus is prevented from falling off from meshes formed between the metal wires; meanwhile, the volume of the metal sleeve in the metal pipe is reduced, so that the pipeline of the metal pipe is smooth, blood can enter the pipeline from the mounting hole and then flow back to the blood pipe, and the blood is prevented from being blocked when thrombus is taken.

Drawings

FIG. 1 is a front view of a thrombus stent in an expanded state in an embolectomy device of the present invention.

FIG. 2 is a cross-sectional view of a thrombus stent within a microcatheter in an thrombectomy device of the present invention.

Fig. 3 is a partially enlarged view of a portion a in fig. 1.

Detailed Description

The following is further detailed by way of specific embodiments:

reference numerals in the drawings of the specification include: the guiding device 1, the guiding piece 11, the kit 12, the micro-catheter 2, the embolectomy stent 3, the metal wire 31, the metal cap 32, the mounting hole 321, the through hole 322, the metal piece 33, the torsion spring 331, the metal sleeve 332, the developing wire 34, the metal tube 35, the mesh 36, the thrombus 4 and the blood vessel 5.

As shown in figures 1, 2 and 3, the thrombus removal device comprises a guide device 1, a micro-catheter 2 and a thrombus removal support 3, wherein the micro-catheter 2 is used for conveying the thrombus removal support 3, and the guide device 1 is used for pushing and pulling the thrombus removal support 3. The embolectomy stent 3 comprises 8 wires 31 and 8 metal caps 32, and the wires 31 and the metal caps 32 are made of shape memory alloy. As shown in fig. 1 and 3, the plurality of metal wires 31 are mutually wound to form an internal cavity, the surface of the metal wires is a cylindrical net-shaped structure, the net-shaped structure is spread and then attached to the inner wall of the blood vessel 5, the right end of the net-shaped structure is gathered by the plurality of metal wires 31 to form a gathering end, the left end of the net-shaped structure is dispersed by the plurality of metal wires 31 to form an open end, and the gathering end is fixedly connected with the guiding device 1; the metal cap 32 is an umbrella-like structure.

As shown in fig. 1, the metal cap 32 is fixedly connected to the open end, and the open end of the metal cap 32 is wound around the mesh structure. The net structure has two or more kinds of net holes 36 with different areas, and in this embodiment, the net structure has two kinds of diamond and triangle. Not only is it advantageous for thrombus 4 of different sizes to enter through the different mesh openings 36, but it is also avoided that thrombus 4 that has just entered the cavity easily slips out of the cavity when being pulled through the different mesh openings 36.

Firstly, after the micro-catheter 2 reaches the position where the thrombus 4 needs to be taken out, the guiding device 1 is pushed, the guiding device 1 drives the thrombus taking support 3 to enter the pipeline of the micro-catheter 2, and the eight metal wires 31 and the metal cap 32 are in a contraction state in the micro-catheter 2. When the metal cap 32 reaches the orifice of the micro-catheter 2 at the thrombus 4, the guide device 1 is stopped being pushed and the micro-catheter 2 is withdrawn, the eight wires 31 and the metal cap 32 are exposed in the blood vessel 5 and gradually expand, so that the eight wires 31 and the metal cap 32 are in a release state, the eight wires 31 form a net structure and are attached to the inner wall of the blood vessel 5, and the thrombus 4 passes through the meshes 36 to enter the cavity, so that the wires 31 capture the thrombus 4. When the guiding device 1 is pulled back again, the thrombus 4 is pulled back into the micro-catheter 2 along with the wire 31, when the capturing force of the wire 31 to the thrombus 4 is insufficient, the thrombus 4 slides from the cavity to the open end, the thrombus 4 at the open end is intercepted by the metal cap 32, and the thrombus 4 is left in the metal cap 32, so that the thrombus 4 is taken out along with the withdrawn metal cap 32.

In order to better avoid the thrombus 4 entering the cavity from falling off from the meshes of the thrombectomy stent 3, in the embodiment, as shown in fig. 1, the thrombectomy stent 3 further comprises a metal piece 33, a developing wire 34 and a metal tube 35, and the guiding device 1 comprises a guiding piece 11 and a sleeve piece 12; the metal cap 32 has a mounting hole 321 at the top thereof. The metal tube 35 is positioned in the cavity, the outer surface of the right end of the metal tube 35 is fixedly connected with the polymerization end, and the left end of the metal tube 35 is fixedly arranged in the mounting hole 321; the metal piece 33 includes a metal sleeve 332 and a torsion spring 331; the metal sleeve 332 is made of memory alloy, the metal sleeve 332 covers the outer surface of the metal cap 32, and the middle part of the metal sleeve 332 extends into the mounting hole 321 and is connected with one end of the torsion spring 331; the other end of the torsion spring 331 is fixedly connected with the metal tube 35, and in a natural state of the torsion spring 331, the part of the metal sleeve 332 located in the metal tube 35 is wound on the outer surface of the torsion spring 331; the guide piece 11 is fixedly connected with the polymerization end, and the guide piece 11 is inserted in the sleeve 12 and is connected with the sleeve 12 in a sliding way; the developing wire 34 is fixedly connected at both ends thereof to the metal sleeve 332 and the sleeve 12, respectively. In this embodiment, the outer surfaces of the metal cap 32 and the metal sleeve 332 are coated with a lubricant coating, and the lubricant coating is applied to avoid damage to the blood vessel 5 caused by the metal cap 32 and the technical sleeve in the pulling process.

After the thrombus 4 is captured by the metal wire 31 and enters the cavity, the sleeve 12 is pulled first, the sleeve 12 drives the development wire 34 to slide outwards relative to the guide member 11, so that the development wire 34 drives the metal sleeve 332 to move from the open end to the polymerization end, the torsion spring 331 rotates to accumulate force, the metal sleeve 332 on the torsion spring 331 is gradually pulled out until the metal sleeve 332 reaches the polymerization end, the metal sleeve 332 wraps the outer surface of the metal wire 31, the guide member 11 and the sleeve 12 are pulled simultaneously, the thrombus 4 is carried by the thrombus taking support 3 to enter the micro-catheter 2, and finally the thrombus 4 is taken out. Therefore, the captured thrombus 4 is prevented from falling off from the meshes 36 formed between the metal wires 31, meanwhile, the volume of the metal sleeve 332 on the torsion spring 331 is reduced, so that the pipeline of the metal tube 35 is unblocked, blood can enter the pipeline of the metal tube 35 from the mounting hole 321 and then flow into the blood vessel 5 below the thrombus 4, and therefore the blood in the blood vessel 5 is prevented from being blocked when the thrombus is taken.

When the thrombus is caught by the thrombus taking support in a blood vessel, in order to better ensure smooth blood, as shown in fig. 1 and 3, in the embodiment, a plurality of through holes 322 are arranged on the cap body of the metal cap 32 at intervals, a plurality of round holes are arranged on the metal sleeve 332, and the round holes correspond to the through holes 322 one by one when the other end of the metal sleeve 332 is pulled to the polymerization end state; thirty-two of the circular holes and the through holes 322 are provided. Blood in the blood vessel 5 can pass through the round hole and the through hole 322 and can enter the thrombus removal support 3 or flow out of the thrombus removal support 3, so that the blood vessel 5 is prevented from being blocked by the thrombus removal support 3, and the blood is not smooth.

Through above technical scheme, realized that the patient can take out thrombus 4 completely at the in-process of getting to tie, can not cause thrombus 4 to drop, can not lead to the problem of secondary embolism.

It should be noted that the above preferred embodiments are only used for illustrating the technical solutions of the present invention, and not for limiting the same; although the present invention has been described in detail with reference to the foregoing embodiments, it will be understood by those of ordinary skill in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some or all of the technical features may be equivalently replaced; these modifications and substitutions do not cause the essence of the corresponding technical solution to depart from the scope of the technical solution of the embodiments of the present invention, and are intended to be covered by the claims and the specification of the present invention.

Claims

1. An embolectomy device, comprising a guiding device, a micro-catheter and an embolectomy support, wherein the micro-catheter is used for conveying the embolectomy support, and the guiding device is used for pushing and pulling the embolectomy support, and is characterized in that: the thrombus removal support comprises a metal cap, a plurality of metal wires, a metal piece, a developing wire and a metal tube, wherein the metal wires and the metal cap are both made of shape memory alloy;

the metal wires are mutually wound to form an internal cavity, the surface of the metal wire is of a cylindrical net structure, one end of the net structure is gathered by the metal wires to form a gathering end, the other end of the net structure is dispersed by the metal wires to form an open end, and the gathering end is fixedly connected with the guiding device;

the metal cap is of an umbrella-shaped structure, the metal cap is fixedly connected with the open end, and the open end of the metal cap surrounds the net-shaped structure;

the guide device comprises a guide piece and a sleeve piece; the top of the metal cap is provided with a mounting hole;

the metal pipe is positioned in the cavity, the outer surface of one end of the metal pipe is fixedly connected with the polymerization end, and the other end of the metal pipe is fixedly arranged in the mounting hole;

the metal piece comprises a metal sleeve and a torsion spring;

the metal sleeve covers the outer surface of the metal cap, and the middle part of the metal sleeve extends into the mounting hole and is connected with one end of the torsion spring;

the other end of the torsion spring is fixedly connected with the metal tube, and the part of the metal sleeve, which is positioned in the metal tube, of the torsion spring is wound on the outer surface of the torsion spring in a natural state;

the guide piece is fixedly connected with the polymerization end, inserted in the sleeve and connected with the sleeve in a sliding manner;

and two ends of the developing wire are respectively fixedly connected with the metal sleeve and the sleeve.

2. The embolectomy device of claim 1, wherein: the net structure has at least two kinds of net holes with different areas.

3. The embolectomy device of claim 1, wherein: the metal cap is characterized in that a plurality of through holes are arranged on the cap body of the metal cap at intervals, a plurality of round holes are sleeved on the metal sleeve, and the round holes correspond to the through holes one to one when the other end of the metal sleeve is pulled to the polymerization end.

4. The embolectomy device of claim 3, wherein: and the outer surfaces of the metal cap and the metal sleeve are coated with lubricating coatings.