CN113440217B

CN113440217B - Thrombectomy device and medical device

Info

Publication number: CN113440217B
Application number: CN202110850136.1A
Authority: CN
Inventors: 王钰富; 扈聪; 王冲
Original assignee: Suzhou Quantong Medical Technology Co ltd
Current assignee: Suzhou Quantong Medical Technology Co ltd
Priority date: 2021-07-27
Filing date: 2021-07-27
Publication date: 2024-12-27
Anticipated expiration: 2041-07-27
Also published as: CN113440217A

Abstract

The invention provides a thrombus taking device and a medical device, wherein the medical device comprises the thrombus taking device, the thrombus taking device comprises a pushing shaft, a thrombus taking support and an auxiliary mechanism, the thrombus taking support is a self-expanding support and is fixedly connected to the distal end of the pushing shaft, and the auxiliary mechanism is partially arranged in the thrombus taking support and is used for applying radially outward expansion force to the thrombus taking support so that the thrombus taking support can also radially execute second expansion after self expansion. And if the thrombus is caught by the thrombus taking device, and the thrombus cannot be effectively caught due to insufficient radial force of the thrombus taking support, the auxiliary mechanism can be used for applying the expansion force to the thrombus taking support, so that the thrombus taking support can be expanded for the second time, the radial force is enhanced, and the thrombus catching effect is improved.

Description

Thrombolysis device and medical device

Technical Field

The invention belongs to the technical field of medical instruments, and particularly relates to a thrombus taking device and a medical device.

Background

Acute cerebral apoplexy is a common cerebrovascular disease, and has the advantages of urgent onset, rapid development, serious symptoms, high disability rate and mortality rate, and belongs to the urgent and critical diseases in cerebrovascular diseases. Generally, cerebral apoplexy can be classified into hemorrhagic cerebral arterial thrombosis and ischemic cerebral arterial thrombosis, wherein the ratio of the ischemic cerebral arterial thrombosis can reach 70% -80%. The pathogenesis of acute ischemic cerebral apoplexy is that thrombus or arteriosclerosis plaque falling off from the wall of a lesion blood vessel causes cerebral artery acute occlusion, and a series of physiological and pathological reactions such as inflammatory reaction, apoptosis and the like are caused by ischemic brain tissue. If the blood flow perfusion of the occluded cerebral artery is restored within a short time, the cellular metabolism of the brain tissue can be restored to be normal, and the development into an infarct area is avoided.

In the prior art, the main treatment methods of acute ischemic cerebral apoplexy include intravenous thrombolysis and interventional thrombolysis. Intravenous thrombolysis is intravenous injection thrombolytic medicine, the treatment time window is within three hours after the occurrence of the disease, however, most patients miss the treatment time window when arriving at a hospital after the occurrence of the disease, so that the thrombolysis effect is seriously reduced, and blocked blood vessels cannot be effectively opened. The interventional embolus is obtained by introducing an embolus removing instrument through femoral artery and removing the embolus by using the embolus removing instrument. The time window for interventional thrombolysis is within eight hours after onset. In recent years, the intervention treatment of acute ischemic cerebral apoplexy has been rapidly developed, and based on a series of clinical random control tests, the related international organizations recommend that the treatment method of interventional thrombus removal can be preferentially considered for patients with large vessel occlusion within six hours.

Interventional thrombolysis can be broadly divided into two categories, mechanical thrombolysis and aspiration thrombolysis. Among these, mechanical embolectomy has been developed to date through iterations of a first generation embolectomy MERCI, a second generation embolectomy Penumbra (consisting of reperfusion catheters and separators) and solitare FR (closed loop stent engraved by laser), a third generation embolectomy Treo (full visualization) and Revive (distal closed mesh basket). The main current mechanical thrombus extraction method is to convey the microcatheter embedded with the thrombus extraction stent into the body with the help of a microcatheter wire, and pass through the thrombus or the gap between the thrombus and the vascular wall to reach the distal side of the thrombus, then withdraw the microcatheter and release the thrombus extraction stent. Therefore, the thrombus can be sunk into the thrombus taking bracket, then the thrombus taking bracket is retracted into the micro-catheter, the thrombus is carried into the micro-catheter, and finally the thrombus taking bracket and the micro-catheter are retracted, so that the thrombus can be moved outside the body. The thrombus capturing method mainly utilizes the radial extrusion and embedding effects of the thrombus capturing bracket on thrombus, and when the radial force of the thrombus capturing bracket is insufficient, the thrombus capturing effect is poor, so that the method has limitation on hard massive thrombus, large-size heart-derived white thrombus or plaque thrombus exceeding a treatment time window.

Disclosure of Invention

The invention aims to provide a thrombus taking device and a medical device, wherein the thrombus taking support of the thrombus taking device can be expanded for the second time under the action of an auxiliary mechanism under the conditions of self expansion and insufficient radial force so as to increase the radial force and improve the thrombus capturing effect.

In order to achieve the above object, the present invention provides a thrombus removing device, comprising:

A pushing shaft;

A thrombus taking support which is a self-expanding support and is fixedly connected with the distal end of the pushing shaft, and

An auxiliary mechanism is partially arranged inside the thrombus-taking bracket and is used for applying radially outward expansion force to the thrombus-taking bracket so that the thrombus-taking bracket can also perform second expansion along the radial direction after self-expansion.

Optionally, the auxiliary mechanism comprises an auxiliary bracket and an expansion rod, wherein the auxiliary bracket is at least partially arranged inside the thrombus taking bracket;

The auxiliary mechanism is configured to drive the auxiliary bracket to expand in the radial direction when the expansion rod moves along a preset direction and generates axial relative motion with the pushing shaft, so that the auxiliary bracket applies the expansion force to the thrombus taking bracket.

Optionally, the proximal end of the auxiliary support is fixedly connected with the distal end of the pushing shaft and/or the proximal end of the thrombus taking support, and the distal end of the auxiliary support is fixedly connected with the distal end of the expansion rod and synchronously moves along with the expansion rod;

The auxiliary mechanism is configured to radially expand the auxiliary stent when the expansion rod is moved in a distal-to-proximal direction in an axial direction of the push shaft.

Optionally, the pushing shaft has a first lumen extending axially therethrough, and the expansion rod is partially disposed through the first lumen and is configured to be movable along the first lumen.

Optionally, the pushing shaft is of a cylindrical spiral spring structure.

Optionally, the expansion rod is disposed in parallel with the pushing shaft.

Optionally, the proximal end and the distal end of the thrombolytic stent are closed ends.

Optionally, the proximal end of the thrombolytic stent is a closed end and the distal end is an open end.

Optionally, the thrombus-taking support is a woven support or a cutting support.

To achieve the above object, the present invention also provides a medical device comprising a microcatheter having a second lumen extending axially therethrough and a thrombectomy device for being partially disposed within and configured to be movable along the second lumen.

Compared with the prior art, the thrombus taking device and the medical device have the following advantages:

The above-mentioned thrombus taking device comprises a pushing shaft, a thrombus taking support and an auxiliary mechanism, wherein the thrombus taking support is a self-expanding support and is fixedly connected with the distal end of the pushing shaft, and the auxiliary mechanism is partially arranged in the thrombus taking support and is used for applying radially outward expansion force to the thrombus taking support so that the thrombus taking support can also radially execute second expansion after self expansion. When the thrombus taking device is used for capturing hard massive thrombus, large-size cardiac-source thrombus or plaque thrombus and the self-expanding radial force of the thrombus taking support is insufficient, the auxiliary mechanism can be used for driving the thrombus taking support to expand secondarily and improving the jogging effect between the thrombus taking support and the thrombus, so that the purpose of capturing the thrombus effectively is achieved.

Drawings

The drawings are included to provide a better understanding of the invention and are not to be construed as unduly limiting the invention. Wherein:

FIG. 1 is a schematic structural view of a thrombus removal device according to an embodiment of the present invention, in which a thrombus removal stent and an auxiliary stent are both in a compressed state;

FIG. 2 is a schematic structural view of a thrombolytic device according to an embodiment of the present invention, wherein the thrombolytic stent is in an expanded state and the auxiliary stent is in a compressed state;

FIG. 3 is a schematic structural view of a thrombus removal device according to an embodiment of the present invention, wherein both the thrombus removal stent and the auxiliary stent are in an expanded state;

FIG. 4 is a schematic structural view of a thrombus removing device according to an embodiment of the present invention, in which the auxiliary mechanism is not assembled with the thrombus removing stand and the pushing shaft;

fig. 5a to 5d are schematic views illustrating a process of removing a thrombus from a medical device according to an embodiment of the present invention.

Reference numerals are described as follows:

100-pushing shaft, 200-thrombus taking support, 300-auxiliary mechanism, 310-auxiliary support and 320-expansion rod;

10-microcatheter, 20-microcatheter wire;

1-thrombosis.

Detailed Description

Other advantages and effects of the present invention will become apparent to those skilled in the art from the following disclosure, which describes the embodiments of the present invention with reference to specific examples. The invention may be practiced or carried out in other embodiments that depart from the specific details, and the details of the present description may be modified or varied from the spirit and scope of the present invention. It should be noted that, the illustrations provided in the present embodiment merely illustrate the basic concept of the present invention by way of illustration, and only the components related to the present invention are shown in the drawings and are not drawn according to the number, shape and size of the components in actual implementation, and the form, number and proportion of the components in actual implementation may be arbitrarily changed, and the layout of the components may be more complex.

In addition, each embodiment of the following description has one or more features, respectively, which does not mean that the inventor must implement all features of any embodiment at the same time, or that only some or all of the features of different embodiments can be implemented separately. In other words, those skilled in the art can implement some or all of the features of any one embodiment or a combination of some or all of the features of multiple embodiments selectively, depending on the design specifications or implementation requirements, thereby increasing the flexibility of the implementation of the invention where implemented as possible.

As used in this specification, the singular forms "a", "an" and "the" include plural referents, unless the content clearly dictates otherwise. As used in this specification, the term "or" is generally employed in its sense including "and/or" unless the content clearly dictates otherwise, and the terms "mounted," "connected," and "connected" are to be construed broadly, as for example, they may be fixed, they may be removable, or they may be integrally connected. It may be a mechanical connection that is made, or may be an electrical connection. Can be directly connected or indirectly connected through an intermediate medium, and can be communicated with the inside of two elements or the interaction relationship of the two elements. The specific meaning of the above terms in the present invention can be understood by those of ordinary skill in the art according to the specific circumstances.

The invention will be further described in detail with reference to the accompanying drawings, in order to make the objects, advantages and features of the invention more apparent. It should be noted that the drawings are in a very simplified form and are all to a non-precise scale, merely for convenience and clarity in aiding in the description of embodiments of the invention. The same or similar reference numbers in the drawings refer to the same or similar parts.

Fig. 1 to fig. 4 are schematic structural views of a thrombus removing device according to an embodiment of the present invention. Referring to fig. 1 to 4, the thrombectomy device includes a pushing shaft 100, a thrombectomy bracket 200, and an auxiliary mechanism 300. The thrombus-taking stent 200 is a self-expanding stent and is fixedly connected to the distal end of the pushing shaft 100. The auxiliary mechanism 300 is partially disposed inside the embolic stent 200 and is used to apply a radially outward expansion force to the embolic stent 200 so that the embolic stent 200 can also perform a second expansion in the radial direction after self-expansion. When the thrombus 1 is captured by the thrombus capturing device (as shown in fig. 5a to 5 d), particularly when a hard large thrombus, a large-size heart-derived white thrombus or a plaque thrombus exceeding a treatment time window is captured, if the radial force generated by the self-expansion of the thrombus capturing bracket 200 is insufficient, the embedding between the thrombus capturing bracket 200 and the thrombus 1 is insufficient, and when the thrombus cannot be captured effectively, an operator can apply an expansion force along the radial direction to the thrombus capturing bracket 200 by operating the auxiliary mechanism 300, so that the thrombus capturing bracket 200 expands for the second time, the embedding effect between the thrombus capturing bracket 200 and the thrombus 1 is improved, and the capturing effect is improved. The self-expanding stent is a stent made of a highly elastic material, which is deformable when a pressure is applied thereto, and which is capable of automatically recovering the deformation by its own elastic force when the pressure is released. The thrombolytic stent 200 may be made of a shape memory alloy such as nitinol, and may be a cut stent or a braided stent, which is not limited in the embodiment of the present invention.

In a specific embodiment, the auxiliary mechanism 300 includes an auxiliary stent 310 and an expansion rod 320, wherein the auxiliary stent 310 is at least partially disposed inside the thrombus removal stent 200, the expansion rod 320 is connected to the auxiliary stent 310, and when the expansion rod 320 moves in a predetermined direction and moves axially relative to the pushing shaft 100, the expansion rod 320 drives the auxiliary stent 310 to expand radially, and when the auxiliary stent 310 continues to expand after expanding radially to a predetermined extent, the auxiliary stent 310 presses the thrombus removal stent 200 inside the thrombus removal stent 200 and applies the expansion force to the thrombus removal stent 200 to push the thrombus removal stent 200 to expand secondarily, thereby enhancing the engagement between the thrombus removal stent 200 and the thrombus 1 and improving the thrombus removal effect.

Preferably, the proximal end of the auxiliary stent 310 is fixedly connected to the distal end of the pushing shaft 100 by welding or any other suitable means, and the distal end of the auxiliary stent 310 is fixedly connected to the distal end of the expansion rod 320 by welding or any other suitable means, so that the distal end of the auxiliary stent 310 moves synchronously with the movement of the expansion rod 320. In this embodiment, the auxiliary stent 310 expands radially when the expansion 320 moves distally to proximally in the axial direction of the pushing shaft 100 (i.e., the aforementioned predetermined direction is the distal to proximal direction), whereas the auxiliary stent 310 contracts radially when the expansion rod 320 moves proximally to distally in the axial direction of the pushing shaft 100. It will be appreciated that the proximal end of the auxiliary stent 310 may be fixedly coupled to the proximal end of the embolic stent 200. And, the auxiliary stent 310 may be made of a shape memory alloy (e.g., nitinol) or a high-elastic polymer material and is pre-formed into an expanded shape such as a sphere or an ellipsoid.

In some implementations, the proximal end and the distal end of the thrombolytic stent 200 are both closed ends, the auxiliary stent 310 is disposed entirely inside the thrombolytic stent 200, and the length of the auxiliary stent 310 is less than or equal to the length of the thrombolytic stent 200. In other implementations, the proximal end of the thrombolytic stent 200 is closed, the distal end is open, the auxiliary stent 310 may be disposed entirely inside the thrombolytic stent 200, or the auxiliary stent 310 may have a length greater than the length of the thrombolytic stent 200, and the auxiliary stent 310 may be disposed partially inside the thrombolytic stent 200, i.e., the distal end of the auxiliary stent 310 may extend outside the thrombolytic stent 200. It is understood that closed ends as described herein refer to respective ends, e.g., proximal ends, of the thrombolytic stent 200 being gathered such that the proximal ends of the thrombolytic stent 200 are formed in a tapered configuration. In addition, the auxiliary stent 310 may be either a woven stent or a cut stent.

Alternatively, the expansion rod 320 may be a solid structure, a hollow structure, a single-strand wire, or a multi-strand wire, which is not limited in the embodiment of the present invention. The expansion rod 320 may be disposed in parallel with the pushing shaft 100, and thus, the pushing shaft 100 may be a solid rod. The materials of the push shaft 100 and the expansion rod 320 may be selected from metallic materials including but not limited to nitinol, or polymeric materials including but not limited to nylon, PTFE (polytetrafluoroethylene), pebax (block polyether amide elastomer).

Preferably, the pushing shaft 100 has a first lumen extending axially therethrough, and the expansion rod 320 is partially disposed in the first lumen and is configured to be movable along the first lumen to radially expand or contract the auxiliary stent 310. In some implementations, the pushing shaft 100 is a tube body, and the single-lumen tube or the multi-lumen tube may be selected according to actual needs, and in other implementations, the pushing shaft 100 is a cylindrical coil spring structure formed by a wire around an axis, which has the advantages of good pushing property and flexibility, and is easier to pass through tortuous vessels.

It should be noted that, when the distal end of the thrombolytic stent 200 is a closed end and the expansion rod 320 is partially and movably inserted into the first lumen of the pushing shaft 100, the distal end of the auxiliary stent 310 may be fixedly connected to the distal end of the thrombolytic stent 200, and the proximal end of the auxiliary stent 310 may be fixedly connected to the distal end of the expansion rod 320. The auxiliary stent 310 may be radially expanded when the expansion bar 320 is moved in the proximal-to-distal direction (i.e., the predetermined direction is the proximal-to-distal direction), and the auxiliary stent 310 may be radially contracted when the expansion bar 320 is moved in the distal-to-proximal direction.

Further, embodiments of the present invention also provide a medical device comprising a microcatheter 10 (as shown in fig. 5 a-5 d) and a thrombectomy device as previously described, the microcatheter 10 having a second lumen extending axially therethrough, the thrombectomy device being for being partially disposed within the second lumen and being configured to be movable along the second lumen.

Next, the use of the medical device will be described herein in connection with simulation experiments.

Experiment preparation:

The middle brain segment of the intracranial vascular model is opened. The experimental rabbits were sampled 5ml from their auricular veins, and the sampled blood was mixed with thrombin and immediately injected into the middle brain segment of the vascular model. Waiting for about 3min to 5min, confirming that blood clots to form thrombus, and closing the middle brain segment of the intracranial vascular model.

Thrombolysis experiment:

first, a micro-wire 20 is introduced into the vascular model at the site where the thrombus 1 is formed.

The distal end of the microcatheter 10 is then delivered along the microcatheter wire 20 to the distal side of the thrombus 1 (as shown in fig. 5 a).

Thereafter, the microcatheter 20 is withdrawn from the vascular model and the distal end of the thrombectomy device is introduced into the second lumen of the microcatheter 10 and the distal end of the thrombectomy stent 200 is delivered along the second lumen to the distal side of the thrombus 1 (as shown in fig. 5 b). It will be appreciated that both the embolic stent 200 and the auxiliary stent 310 are in a contracted state during this procedure.

Subsequently, the microcatheter 10 is withdrawn (i.e., the microcatheter 10 is moved in a distal-to-proximal direction) and the embolic stent 200 is self-expanding (as shown in fig. 5 c).

Next, the expansion rod 320 is retracted (i.e., the expansion rod 320 is moved in the distal-to-proximal direction), causing the auxiliary stent 310 to radially expand and causing the auxiliary stent 310 to press the thrombolytic stent 200 inside the thrombolytic stent 200 and apply a radial expansion force to the thrombolytic stent 200, causing the thrombolytic stent 200 to secondarily expand (as shown in fig. 5 d) and effectively catch thrombus 1.

After confirming that the thrombus 1 is completely caught by the thrombus-taking device, the expansion member 320 is pushed forward (i.e., the expansion member 320 is moved in the proximal-distal direction), and the auxiliary stent 310 is contracted in the radial direction. The thrombus removal device is then withdrawn until it is retrieved into the microcatheter 10. Finally, the microcatheter 10 and the thrombus 1-carrying thrombus removal device are entirely withdrawn from the vessel model.

It will be appreciated that when the radial force of the stent 200 is sufficiently high and the stent 200 is effective to capture a thrombus, the stent 200 may be expanded for a second time without the auxiliary stent 310, i.e., the auxiliary stent 310 is always in a compressed state during the capture of a thrombus.

According to the technical scheme provided by the embodiment of the invention, when the radial force of the thrombus taking support is insufficient and thrombus is difficult to be effectively caught, the auxiliary mechanism can be utilized to provide radial expansion force for the thrombus taking support in the thrombus taking support, the thrombus taking support is expanded for the second time, the jogging effect of the thrombus taking support and thrombus is improved, the catching capability of thrombus is enhanced, and the thrombus taking effect is improved. The thrombus taking device provided by the embodiment of the invention is particularly suitable for catching hard massive thrombus and large-size cardiac thrombus and plaque thrombus.

Although the present invention is disclosed above, it is not limited thereto. Various modifications and alterations of this invention may be made by those skilled in the art without departing from the spirit and scope of this invention. Thus, it is intended that the present invention also include such modifications and alterations insofar as they come within the scope of the appended claims or the equivalents thereof.

Claims

1. A thrombolytic device, comprising:

A pushing shaft;

The auxiliary mechanism comprises an auxiliary bracket and an expansion rod, wherein the auxiliary bracket is at least partially arranged in the thrombus taking bracket, the proximal end of the auxiliary bracket is fixedly connected with the distal end of the pushing shaft and/or the proximal end of the thrombus taking bracket, and the distal end of the auxiliary bracket is fixedly connected with the distal end of the expansion rod and synchronously moves along with the expansion rod;

The auxiliary mechanism is configured to expand the auxiliary stent radially and apply a radially outward expansion force to the thrombolytic stent when the expansion rod is moved in a distal-to-proximal direction in an axial direction of the push shaft, so that the thrombolytic stent can also perform a second expansion in the radial direction after self-expansion.

2. The thrombectomy device of claim 1, wherein the push shaft has a first lumen extending axially therethrough, the expansion rod partially disposed through the first lumen and configured to be movable along the first lumen.

3. The thrombectomy device of claim 2, wherein the pusher shaft is a cylindrical coil spring structure.

4. The thrombectomy device of claim 1, wherein the expansion rod is disposed in parallel with the push shaft.

5. The thrombectomy device of claim 1, wherein the proximal and distal ends of the thrombectomy stent are closed ends.

6. The thrombectomy device of claim 1, wherein the proximal end of the thrombectomy stent is closed and the distal end is open.

7. The thrombolytic device of claim 1, wherein said thrombolytic stent is a braided stent or a cut stent.

8. A medical device comprising a microcatheter having a second lumen extending axially therethrough and a thrombectomy device of any one of claims 1-7 for being partially disposed within and configured to be movable along the second lumen.