WO2014081077A1

WO2014081077A1 - Stent module for removing blood clots

Info

Publication number: WO2014081077A1
Application number: PCT/KR2013/000409
Authority: WO
Inventors: 이종혁; 김영호
Original assignee: 연세대학교 원주산학협력단
Priority date: 2012-11-26
Filing date: 2013-01-18
Publication date: 2014-05-30
Also published as: KR101303612B1

Abstract

A stent module comprises a stent, a push wire and an expandable guiding catheter. The stent has a mesh unit connected so as to enable all of proximal markers and distal markers at both ends to close, and a middle part thereof has a low number of strut forms. The push wire pushes the stent toward a blood vessel at which blood clots are located. The expandable guiding catheter, in an expanded state after entering the blood vessel, moves a micro-catheter, which guides the stent and the push wire, into the blood vessel, or retrieves the stent collecting blood clots, and the push wire at the outside of the blood vessel.

Description

Thrombosis Stent Module

The present invention relates to a stent module, and more particularly, to a thrombus removal stent module with improved thrombus removal efficiency.

In general, if the cerebral artery, peripheral artery, deep vein, pulmonary artery, etc. are blocked by thromboembolism, thrombolytic treatment using drugs or mechanical thrombolysis is used.

In particular, in the case of mechanical thrombectomy, various thrombus removal mechanisms have been developed, and among the thrombus removal mechanisms developed to date, the solitaire stent shown in FIG. 1 is known to be excellent in terms of effectiveness.

The soliter stent 10 is a push wire 12 for pushing the stent along the micro-conduit or conduit 11, and the mesh portion 14 connected to the push wire 12 end to remove the blood clot at the place where the thrombus is located. ). In this case, the mesh portion 14 is formed between the proximal marker 13 and the distal markers 15 so that bundles of strands are entangled with each other, thereby making it easy to remove the thrombus. Have

However, the mesh unit 14 includes one adjacent point 13 and a plurality of circular contact points 15. In the case of the circular contact point 15, a plurality of mesh points 14 are disposed in an open shape. Thus, in the case of the soliter stent 10, when the thrombus is removed, the contact point 15 is kept open and the thrombus is located outside the stent, so the thrombus is not effectively removed, so the thrombus removal procedure must be attempted several times or thrombus During removal, the thrombus separates from the stent and causes distal movement. In addition, when the mesh portion 14 and the push wire 12 are introduced into the induction conduit 16 together with the conduit or the microconduit 11 after the thrombus is captured, the inlet of the induction conduit 16 becomes a thrombus. Because it is narrower than this captured stent, blood clots are often not removed, but detach from the stent and move distal to the vessel, causing new infarction.

Accordingly, the technical problem of the present invention was conceived in this respect, the object of the present invention relates to a stent module to improve the efficiency of blood clot removal and reduce the complications that can occur during blood clot removal.

The stent module according to an embodiment for realizing the object of the present invention includes a stent, a push wire and an expandable induction conduit. The stent has a mesh portion connected to close both the adjacent point and the original contact point at both ends. The push wire pushes the stent toward the blood vessel where the thrombus is located. The expanded induction conduit enters the vessel and expands the microconduit inducing the stent and the push wire into the vessel or recovers the stent and the push wire from which the thrombus is taken out of the vessel.

In some embodiments, the stent may include a first mesh part connected to the first contact point, a second mesh part connected to the first mesh part, and a third mesh part connected to the second mesh part and the adjacent point. have.

In one embodiment, the one contact point and the adjacent point is each one, each of the first and third mesh portion may form a bundle by branching from the contact point and the adjacent point.

In one embodiment, each of the first and third mesh portions may include a greater number of meshes than the second mesh portion.

In one embodiment, the first mesh portion may be longer than the third mesh portion.

In one embodiment, the stent is connected to the push wire to move to the place where the thrombus is located, the first, second and third mesh portion is retracted as the micro-conduit withdraws while the push wire is fixed It can be extended radially to collect the thrombi.

In an embodiment, the thrombus collected by the stent may be blocked from being left outside the stent by the far point and the first mesh portions while being recovered along the blood vessel.

In one embodiment, the expandable induction conduit may include an entry portion and an extension portion extending from the entry portion and extending radially in the state of entering the blood vessel.

In one embodiment, the proximal and distal ends of the extension are marked with a radiopaque material, and the extension can be extended by a length corresponding to the length of the stent.

In one embodiment, the expanded radius of the extension may be greater than the radius of the stent extension.

In one embodiment, the stent from which the thrombus is taken may be drawn into the expanded portion in an expanded state, and then recovered into the entry portion with decreasing radius.

In one embodiment, the expanded induction conduit may be reduced in the radius of expansion when the stent from which the thrombus is collected is recovered outside the blood vessel.

According to the embodiments of the present invention, since the first mesh portion of the stent has a bundle structure closed by branching from a single contact point, the thrombus removal rate may be improved by increasing the fixing force for fixing the thrombus.

In addition, since the strut of the second mesh portion is formed less than the mesh of the first mesh portion, the blood vessels within the blood vessel can be easily captured into the stent.

In addition, since the induction conduit expands radially in the state of entering the blood vessel, compared to the case where the stent from which the thrombus is collected is directly recovered to a narrow radius entry portion, the possibility of thrombus remaining in the blood vessel is minimized to reduce the thrombus removal rate. It can improve and prevent complications caused by the migration of remaining thrombi. In particular, even though some blood clots are left as the stent is recovered to the expanded entry part, the blood clots remain in the extension part of the expanded induction conduit, so that they can be easily discharged or removed by applying a negative pressure naturally or through a syringe without moving to the distal end of the vessel. Can be. This natural discharge is possible because the pressure in the vessels is higher than the external atmospheric pressure.

1 is a perspective view showing a solitaire stent according to the prior art.

2 is a perspective view showing a stent module according to an embodiment of the present invention.

FIG. 3A is a cross-sectional view taken along line II ′ of FIG. 2.

FIG. 3B is a cross-sectional view taken along line II-II 'of FIG. 2.

4A is a perspective view illustrating a state in which the expanded induction conduit of FIG. 2 is not expanded.

4B is a perspective view illustrating an expanded state of the induction conduit of FIG. 2.

5A to 5F are schematic views illustrating a blood clot removal method using the stent module of FIG. 2.

* Explanation of the sign

20: stent module 30: stent

36: push wire 50: expanded induction conduit

52, 53: extension

As the inventive concept allows for various changes and numerous modifications, the embodiments will be described in detail in the text. However, this is not intended to limit the present invention to a specific disclosed form, it should be understood to include all modifications, equivalents, and substitutes included in the spirit and scope of the present invention. In describing the drawings, similar reference numerals are used for similar elements. Terms such as first and second may be used to describe various components, but the components should not be limited by the terms. The terms are used only for the purpose of distinguishing one component from another. The terminology used herein is for the purpose of describing particular example embodiments only and is not intended to be limiting of the present invention. Singular expressions include plural expressions unless the context clearly indicates otherwise. In this application, the terms "comprise" or "consist of" are intended to indicate that there is a feature, number, step, operation, component, part, or combination thereof described in the specification, and one or more other features. It is to be understood that the present invention does not exclude the possibility of the presence or the addition of numbers, steps, operations, components, parts, or combinations thereof.

Unless defined otherwise, all terms used herein, including technical or scientific terms, have the same meaning as commonly understood by one of ordinary skill in the art. Terms such as those defined in the commonly used dictionaries should be construed as having meanings consistent with the meanings in the context of the related art and shall not be construed in ideal or excessively formal meanings unless expressly defined in this application. Do not.

Hereinafter, with reference to the accompanying drawings, it will be described in detail a preferred embodiment of the present invention.

2 is a perspective view showing a stent module according to an embodiment of the present invention. FIG. 3A is a cross-sectional view taken along line II ′ of FIG. 2. FIG. 3B is a cross-sectional view taken along line II-II 'of FIG. 2.

Referring to FIG. 2, the stent module 20 according to the present embodiment includes a stent 30, a push wire 36, a fine conduit 40, and an expanded induction conduit 50. The stent module 20 shown in FIG. 2 illustrates a state where the stent 30 is located where blood clots are present, that is, at the moment of collecting blood clots, and the overall operation of the stent module 20 is illustrated in FIG. 5A. It will be described later with reference to Figure 5f.

The stent 30 includes a mesh portion having first and

second mesh portions

33, 34, and 35 having a circular contact point 31 and an adjacent point 32 at both ends. The first contact point 31 is defined as a contact point where the first mesh part 33 is collected at a position furthest from the end of the push wire 36, and the adjacent point 32 is a contact point of the push wire 36. The third mesh part 35 is defined as a contact point at which the third mesh part 35 starts to unfold to the position closest to the end. As will be described later, the stent 30 and the push wire 36 is moved to the place where the thrombus exists along the inside of the micro-conduit 40, the micro-conduit 40 is expanded in the radial direction as it retreats It is arranged in the shape shown in 2.

In this embodiment, both the original contact point 31 and the adjacent point 32 are one. That is, in the conventional stent shown in FIG. 1, although the adjacent point 13 is one, a plurality of the contact points 15 are formed, and the stent has a net structure in which the part of the contact point 15 is open. .

However, in this embodiment, not only the adjacent point 32, but also the original contact point 31 is formed as one, the stent has a network structure of both ends closed form. That is, the first mesh part 33 is unfolded in the form of a net from the one contact point 31, and the third mesh part 35 is also unfolded in the form of a net from the one adjacent point 32.

Further, in the stent 30 according to the present embodiment, the first and

third mesh portions

33 and 35 corresponding to both ends of the mesh portion are connected between the first and

third mesh portions

33 and 35. It has a denser net form than the second mesh portion 34 to be. That is, the first and

third mesh portions

33 and 35 have a larger number of meshes than the second mesh portion 34.

In this regard, referring to FIGS. 3A and 3B, for example, the first mesh part 33 may be branched into six from the origin contact point 31 to form a mesh, and the second mesh part ( 34 may form three strands of struts extending along the contact point 36 where the two nets of the first mesh portion 33 merge into one. Alternatively, although not shown, the first mesh portion 33 may be divided into eight to form a net, and the second mesh portion 34 may form four strands of struts. On the other hand, although not shown in cross-sectional view, the three strands or four strands of the net combined in the second mesh portion 34 is formed in the third mesh portion 35 again six or eight meshes after the adjacent point ( 32) can be formed into a structure that is collected.

The number of meshes or struts of the first, second, and

third mesh parts

33, 34, and 35 may be variously modified in consideration of the size of the thrombus to be removed and the thickness of the blood vessel.

As described above, in the present embodiment, the first mesh portion 33 branches from the one contact point 31, and the first mesh portion 33 forms a finer net than the second mesh portion 34. Therefore, when the stent 30 is collected in the direction of the expandable induction conduit 50 after collecting the thrombus, the collected thrombus is more stable by the far contact point 31 and the first mesh portion 33. Since the sample is strongly collected, the collected blood clot can be minimized from remaining in the blood vessel.

Meanwhile, the first mesh part 33 may have a length longer than that of the third mesh part 35, that is, a long mesh section may be formed to capture sufficient blood clots.

In addition, the second mesh portion 34 is composed of three to four struts (struts) without forming a net and the number thereof is relatively smaller than that of the first mesh portion, so that blood clots in the blood vessels are easily captured in the stent. In addition, damage to the blood vessel caused by the second mesh part 34 may be minimized when the stent 30 is recovered.

The push wire 36 connecting the stent 30 and the stent enters the blood vessel through the microconduit 40 and then moves along the microconduit 40 to the place where the thrombus is finally located. Thereafter, the micro-conduit 40 is retracted in the direction of the expanded induction conduit 50, the stent 30 and the push wire 36 is exposed while expanding the blood vessel in which the thrombus in the form shown in FIG. It is placed inside.

As such, the stent 30 and the push wire 36 are positioned in the target blood vessel in which the blood clot is present according to the guide of the micro-conduit 40. In particular, the blood vessels needing to remove the thrombus are small vessels of very small radius, so that the stent 30 and the pushwire 36 may move along the vessels of a complicated structure to the place where the thrombus is located. However, the stent 30 may cause damage to the normal blood vessel when the stent 30 is advanced along the blood vessel to remove the blood clot, and thus, the stent 30 may be moved to the place where the blood clot is located through the micro-conduit 40. Can be moved to prevent damage to blood vessels and stents. On the contrary, even when the stent is expanded, the pull wire can be pulled to recover the stent, so that the stent is deformed to some extent according to the cross-sectional area of the blood vessel.

The expandable induction conduit 50 includes an entry portion 51 and

expansion portions

52, 53. The entry part 51 enters the blood vessel through the insertion tube 55 to form a guide through which the microconduit, the stent 30, and the push wire 36 may enter the blood vessel. In addition, when blood clots are removed by the stent 30, a passage for collecting the stent 30, the push wire 36, and the microconduit 40 is formed.

On the other hand, blood vessels that require removal of blood clots are generally small blood vessels such as small blood vessels, and the expanded induction conduit 50 cannot enter a blood clot, and is located in a blood vessel having a relatively large radius. Let's do it. In addition, the stent 30 and the push wire 36 are guided from the expanded induction conduit 50 to the blood vessel in which the thrombus is located through the microconduit 40 as described above.

In the present embodiment, the expandable induction conduit 50 includes

extensions

52 and 53, which will be described with reference to FIGS. 4A and 4B at the same time.

4A is a perspective view illustrating a state in which the extension of FIG. 2 is not expanded. 4B is a perspective view illustrating an expanded state of FIG. 2.

That is, referring to FIGS. 2 and 4A, when the expandable induction conduit 50 enters a blood vessel, the expansion part 52 remains unexpanded and has the same size as that of the entry part 51. Have a radius.

2 and 4B, when the expandable induction conduit 50 enters the blood vessel along the guide wire 54 and moves to the proximal target position of the blood vessel where the blood clot is located along the guide wire 54. The expansion 53 is expanded. The method used for inflation uses a balloon catheter expansion method.

Specifically, the expansion portion 52 of the expandable induction conduit 50 is expanded in the radial direction to expand the volume. In this case, the radius of the expanded expansion 53 is preferably smaller than the radius of the vessel in order to maintain blood flow without damaging the vessel in which the extension of the expanded guide conduit 50 is located. However, it is preferable that the radius of the expanded extension 53 is slightly larger than the radius of the expanded stent 30. Thus, the stent 30 from which the thrombus is collected may be introduced into the expanded expansion part 53 without reducing the radius, and since the radius of the stent 30 is not reduced, the collected thrombus is separated from the blood vessel. Or the probability of remaining is minimized.

On the other hand, the expansion portion 52 of the expandable induction conduit 50, the proximal and distal portions are marked with a radiopaque material to prevent damage to the expandable induction conduit during expansion of the balloon to the extension (52). The length of the expanded expansion 53 is the same as or longer than the length of the stent 30 is that the stent 30 from which the blood clots can be drawn into the inside of the expanded expansion 53 desirable.

The expanded portion 53 of the expanded induction conduit is the blood vessel entry portion after the stent 30 and the push wire 36 and the fine conduit 40 from which blood clots are collected at the same time The volume that has been inflated by the insertion tube 55 located therein is reduced and is recovered to the outside of the blood vessel together with the entry part 51.

The stent 30 and the push wire 36 from which blood clots are collected are introduced into the expanded expansion part 53 together with the micro-conduit 40 and then externally through the entry part 51. Is recovered. In this case, the first, second and

third mesh portions

33, 34, and 35 of the stent 30 are recovered to the entry part 51 while the radius thereof is reduced, and thus, the stent 30 may be recovered. The thrombus radius that was collected by the battery is reduced to the entrance part 51. However, since the sampled thrombus varies in size, type, and strength, the mesh portion of the stent 30 may be reduced or partially cut off and remain in the expanded expansion portion 53 of the expanded induction conduit rather than a blood vessel. have. In this case, the remaining thrombi can be easily discharged to the outside because the pressure in the blood vessel is higher than the external atmospheric pressure, and if the size is difficult to naturally discharge, it can be easily removed by applying a negative pressure using a syringe or the like. Thus, the amount of blood clots remaining in the blood vessel can be minimized.

5A and 5B, after the expanded induction conduit 50 according to the present embodiment enters the inside of the entry vessel 62, the entry into narrow vessels such as a small artery in which the thrombus 63 is located is performed. The wire 41 and the fine conduit 40 enter. In this case, in order to move to the place where the thrombus 63 is located, it must move along the blood vessel of a very complicated structure without damaging the blood vessel, and thus, an appropriate entry wire 41 and a micro conduit 40 should be selected.

Referring to FIG. 5C, when the microconduit 40 is located to the distal portion of the blood vessel in which the thrombus is located, the entry wire 41 is recovered to prepare for entering the stent 30 and the push wire 36.

Referring to FIG. 5D, the stent 30 and the push wire 36 are advanced along the inside of the micro-conduit 40 to the blood vessel region where the thrombus 63 is located so that a thrombus is formed between the stent contact point and the adjacent point. After adjusting to position, the stent 30 is exposed while recovering the micro-conduit 40 in the direction opposite to the entry direction. The exposed stent 30 is radially inflated in the order of the first mesh portion 33, the second mesh portion 34, and the third mesh portion 35 to be positioned in the thrombus 63. The radially expanded first, second and

third mesh portions

33, 34, 35 capture the thrombus 63.

Referring to FIG. 5E, the expansion part 52 of the expandable induction conduit 50 disposed near the entry vessel 62 before the process of FIG. 5A is previously inflated 53 in a radial direction using a balloon catheter. .

Referring to FIG. 5F, the stent 30 is recovered in the direction of the entry vessel 62 opposite to the entry direction while capturing the thrombus 63, and finally, of the expansion catheter 53. It is recovered internally. In this case, as the stent 30 is recovered, the thrombus 63 is relatively gathered into the first mesh portion 33 of the stent 30. In this embodiment, the first mesh portion 33 is Since the network structure branched from the contact point 31, the thrombus 63 is minimized to remain outside of the first mesh part 33 of the stent 30.

Thereafter, although not shown, the stent 30 is recovered outside the blood vessel through the entry part 51 together with the collected thrombus 63 while the radius of the mesh part is reduced. At this time, the falling or leaving the thrombus remains in the expanded expansion 53, the residual thrombus is naturally discharged by the difference between the internal pressure of the blood vessel and the external atmospheric pressure, or forced to apply a negative pressure through a syringe or the like Aspiration is removed. When the expanded induction conduit is recovered to the outside of the blood vessel, the expanded portion 53 is reduced by the insertion tube 55 and is recovered out of the blood vessel together with the entry part 51.

As described above, the stent module 20 according to the present embodiment can effectively remove the blood clot 63 because the blood clot 63 is located inside the stent, and minimize the blood clot separated into blood vessels during blood clot removal using the stent. Thus, complications associated with the procedure can be reduced.

According to the embodiments of the present invention as described above, since the first mesh portion of the stent has a bundle structure closed by branching from one circle contact point, the thrombus removal rate may be improved by increasing the fixing force for capturing and fixing the thrombi. Can be.

In addition, by forming the strut of the second mesh portion less than the mesh of the first mesh portion, the thrombi can be easily located inside the stent.

In addition, the expanded induction conduit includes an expansion part, and the expansion part of the expansion induction conduit expands radially in the state where the blood vessel enters the blood clot, compared with the case where the stent from which the thrombus is collected is directly recovered to a narrow radius entry part. By minimizing the chance of remaining in these vessels, they can improve blood clot clearance and reduce complications caused by isolated blood clots. In particular, since the thrombi left while the stent is recovered to the entry part remains inside the extension part of the expandable induction conduit, the residual thrombus is naturally discharged due to the difference between the internal pressure of the blood vessel and the external atmospheric pressure, or a negative pressure is applied through a syringe or the like. It can be forcibly removed by suction.

The stent module according to the present invention has industrial applicability that can be used for mechanical procedures for removing blood vessels and the like when they are blocked by blood clots.

Claims

A stent having a mesh part connected to close both the adjacent point and the original contact point of both ends;

A push wire for pushing the stent toward a blood vessel in which a thrombus is located; And

A stent module including an expanded induction conduit for returning the stent and the push wire guided micro-conduit into the vessel in the state of entering the blood vessel inlet, or recovering the stent and the push wire from the blood vessel outside the vessel.
The method of claim 1, wherein the stent,

A first mesh part connected to the circle contact point;

A second mesh part connected to the first mesh part; And

The stent module comprising a second mesh portion and a third mesh portion connected to the adjacent point.
The method of claim 2, wherein the one contact point and the adjacent point each one,

Each of the first and third mesh portions branch from the original contact point and the adjacent point to form a bundle.
4. The stent module of claim 3, wherein each of the first and third mesh portions comprises a greater number of meshes than the strut of the second mesh portion.
The stent module of claim 3, wherein the first mesh part has a length longer than that of the third mesh part.
The first, second and third mesh portions of claim 1, wherein the stent is connected to the push wire to move to a place where a blood clot is located, and as the micro-conduit is retracted while the push wire is fixed. The stent module, characterized in that the radially extended to collect the thrombus.
The stent module of claim 6, wherein the thrombus collected by the stent is blocked from being left outside of the stent by the first contact point and the first mesh portions while being recovered along the blood vessel.
The method of claim 1, wherein the expanded induction conduit,

Entry; And

A stent module extending from the entry portion, comprising an extension extending radially in the state of entering the blood vessel.
9. The stent module of claim 8, wherein the proximal and distal ends of the extension are marked with a radiopaque material, and the extension extends by a length corresponding to the length of the stent.
The stent module of claim 8, wherein an expanded radius of the extension is greater than an extended radius of the stent.
The stent module of claim 8, wherein the stent from which the thrombus is taken is introduced into the expansion part in an expanded state and then recovered to the entry part with a decrease in radius.
12. The stent module of claim 11, wherein the expandable induction conduit has a radius that has been expanded when the stent from which the thrombus is collected is recovered to the entry portion.