CN116407335A - Stent Graft and Stent Graft Delivery System - Google Patents

Abstract

The invention relates to a covered stent and a delivery system for the covered stent. The covered stent includes: a self-expandable tubular body, a deformable first corrugated coil, and a second corrugated coil. The tubular main body includes an end section with an open end. , the first wave ring is movably connected with the end section, and the second wave ring is connected with the end section; when the end section is radially compressed to the first state, the first wave ring can at least partially pass over the open end , when the end segment radially expands from the first state to the second state, the first wave ring is located in the axial area where the end segment is located, and the axial area where the first wave ring is located is the same as the axial area where the second wave ring is located The axial regions at least partially overlap. The covered stent and the covered stent delivery system of the present invention can improve the stimulation and damage of the covered blood vessel during the release process of the covered stent.

Description

Stent Graft and Stent Graft Delivery System

technical field

The invention relates to the technical field of interventional medical devices, in particular to a covered stent and a delivery system for the covered stent.

Background technique

In the past ten years, endovascular exclusion with covered stents has been widely used in thoracic and abdominal aortic aneurysms and arterial dissections. It has definite curative effect, less trauma, faster recovery and fewer complications, and has become the first-line treatment. method. The grafted stent includes a support frame and a film covered on the support frame. During the operation, the stent-graft is radially compressed and loaded in the delivery sheath of the conveyor, and the stent-graft is delivered to the lesion position through the conveyor, and then the stent-graft is implanted into the lesion, and the stent-graft directs blood It is isolated from the lesion and eliminates the influence of blood pressure on the lesion to achieve the purpose of healing.

However, for the self-expandable stent-graft, under the action of self-expansion and deployment, the stent-graft will radially outwardly adhere to the inner wall of the sheath. In this case, the stent is released, and when the sheath is withdrawn, the stent-graft moves accordingly, and the stent-graft cannot be released at the predetermined lesion position.

By setting the bare stent section (that is, the supporting skeleton section without the stent graft) at the end of the stent-graft, the bare wave coil is connected to the conveyor to realize the axial limit during the delivery process, thereby preventing the back of the sheath. Withdrawal drives the displacement of the covered stent, increasing the accuracy of the release of the stent. However, due to the self-expanding characteristics, the bare stent will produce a large radially outward elastic force during the release process, which directly acts on the inner wall of the blood vessel, which may cause greater irritation to the blood vessel, especially the protruding part of the bare stent segment. The crest, which is less constrained, is more prone to damage the vessel during release.

Contents of the invention

Based on this, the present invention proposes a stent-graft and a stent-graft delivery system, which aim to improve the stimulation and damage of the blood vessel during the release of the stent-graft.

For reaching this purpose, the present invention adopts following technical scheme:

Covered stents, including:

a self-expanding tubular body comprising an end section having an open end;

a deformable first wave ring, the first wave ring is movably connected with the end section;

a second wave coil connected to the end segment;

When the end section is radially compressed to a first state, the first wave coil can at least partially pass over the open end, and when the end section is radially expanded from the first state to a second state, the first wave coil is located in the axial region where the end section is located, and the axial area where the first wave coil is located overlaps at least partially with the axial area where the second wave coil is located.

In one of the embodiments, when the end segment is in the second state, the axial area where the first wave coil is located is located within the axial area where the second wave coil is located.

In one embodiment, the second wave coil is fixedly connected to the end section, and the second wave coil is located in an axial region where the end section is located.

In one of the embodiments, the end section includes an end coating, and when the end section is in the second state, the end coating covers the second wave coil and the first wave coil of the outer surface.

In one of the embodiments, the end coating includes an outer coating, the outer coating is located on the outside of the second wave coil, the second wave coil includes an inner exposed section, and the inner The inner surface of the exposed section of the layer is exposed, and the first corrugated coil is connected to the second corrugated coil through the exposed section of the inner layer.

In one of the embodiments, at least one limiting channel is provided between the second wave coil and the outer film, the first wave coil includes a wave-shaped ring structure formed by a first support wire, and the The first support wire passes through the limiting channel, so that the first wave coil is movably connected to the end section.

In one of the embodiments, the end coating further includes an inner coating, the second wave coil further includes an inner coating segment, and the inner surface of the inner coating segment covers the inner coating , both ends of the exposed inner layer section are connected to the inner film-coated section, the exposed inner layer section, the outer layer film, and the inner layer film covered on the inner surface of the inner layer film section are enclosed to form The limiting channel.

In one of the embodiments, the stent-graft further includes a flexible connection, the first wave ring is connected to the end section through the flexible connection, and the first wave ring can move axially movement relative to the end section.

In one of the embodiments, the movable link includes a slender link, one end of the slender link is connected to the first corrugated coil, and the other end is connected to the exposed section of the inner layer, and the slender link At least one end of the connector is a fixed connection end.

In one of the embodiments, the first wave ring includes a plurality of first wave troughs and first wave crests, and the first wave troughs are respectively connected to the exposed inner layers on both sides of the first wave troughs through two elongated connecting pieces. section; and/or, the first crest is respectively connected to the exposed inner section on both sides of the first crest through two elongated connectors.

In one embodiment, the first wave coil includes a plurality of first wave troughs and a plurality of wave rods, the second wave coil includes a plurality of second wave crests and a plurality of second wave troughs, and the first wave troughs pass through Two elongated connecting pieces are respectively connected to the second wave troughs on both sides of the first wave trough; and/or, the second wave crest is respectively connected to the on the pole of the first wave circle.

In one of the embodiments, the wave angle of the second wave coil is smaller than the wave angle of the first wave coil, and the wave bar of the second wave coil is smaller than or equal to the wave bar of the first wave coil.

A stent-graft delivery system, comprising a conveyor and the stent-graft as described above, the conveyor is used to deliver the stent-graft, the conveyor includes a sheath core, the distal end of the sheath core An anchoring part is provided, and when the stent-graft is loaded in the conveyor, the anchoring part is connected with the first corrugated coil passing over the opening end.

In the stent-graft and the stent-graft delivery system of the present invention, a deformable first wave coil is arranged at the opening end of the self-expanding stent-graft, so that in the loaded state, the first wave coil can deform and pass over the opening end Connected with the conveyor, thereby preventing the sheath from withdrawing and driving the stent-graft to shift, increasing the accuracy of the stent-graft release; in addition, during the release of the stent-graft, the first wave coil deforms and retreats into the tubular body In the axial region where the end section of the tubular body is located, the end section of the tubular body will form a certain degree of restraint on the first wave coil, reducing the stimulation and damage to the blood vessel during the release process of the first wave coil.

Description of drawings

1 is a schematic diagram of a stent graft in a natural state according to an embodiment of the present invention;

Fig. 2 is a schematic diagram of the stent graft in Fig. 1 in a radially compressed state;

Fig. 3 is a schematic plan view of the end section in Fig. 1;

Fig. 4 is a schematic diagram of planar expansion of the limiting channel in Fig. 3;

Fig. 5 is a schematic plan view of the end section in another embodiment of the present invention;

Fig. 6-Fig. 8 are the planar development diagrams of the end section in another embodiment of the present invention;

Fig. 9 is a schematic structural diagram of a stent graft delivery system in an embodiment of the present invention.

Detailed ways

In order to make the objects, technical solutions and advantages of the present invention more clear, exemplary embodiments of the present disclosure will be described in more detail below with reference to the accompanying drawings. Although exemplary embodiments of the present disclosure are shown in the drawings, it should be understood that the present disclosure may be embodied in various forms and should not be limited by the embodiments set forth herein. Rather, these embodiments are provided for more thorough understanding of the present disclosure and to fully convey the scope of the present disclosure to those skilled in the art.

It should be understood that the terminology used herein is for the purpose of describing particular example embodiments only and is not intended to be limiting. As used herein, the singular forms "a", "an" and "the" may also be meant to include the plural forms unless the context clearly dictates otherwise. The terms "comprising", "comprising", "containing" and "having" are inclusive and thus indicate the presence of stated features, steps, operations, elements and/or parts but do not exclude the presence or addition of one or Various other features, steps, operations, elements, components, and/or combinations thereof. The method steps, processes, and operations described herein are not to be construed as necessarily requiring their performance in the particular order described or illustrated, unless an order of performance is specifically indicated. It should also be understood that additional or alternative steps may be used.

Although the terms first, second, third, etc. may be used herein to describe various elements, components, regions, layers and/or sections, these elements, components, regions, layers and/or sections should not be referred to as These terms are limited. These terms may be only used to distinguish one element, component, region, layer or section from another region, layer or section. Terms such as "first," "second," and other numerical terms when used herein do not imply a sequence or order unless clearly indicated by the context. Thus, a first element, component, region, layer or section discussed below could be termed a second element, component, region, layer or section without departing from the teachings of the example embodiments.

For the convenience of description, spatial relative terms may be used herein to describe the relationship of one element or feature as shown in the figures with respect to another element or feature, such as "inner", "outer", "inner". ", "Outside", "Below", "Below", "Above", "Above", etc. Such spatially relative terms are intended to encompass different orientations of the device in use or operation in addition to the orientation depicted in the figures. For example, if the device in the figures is turned over, elements described as "below" or "beneath" other elements or features would then be oriented "above" or "beneath" the other elements or features. feature above". Thus, the example term "below" can encompass both an orientation of above and below. The device may be otherwise oriented (rotated 90 degrees or at other orientations) and the spatially relative descriptors used herein interpreted accordingly.

In addition, in order to describe the structure of the present application more clearly, the terms "proximal end" and "distal end" are defined here as commonly used terms in the field of interventional medicine. Specifically, "distal end" refers to the end where blood flows out, and "proximal end" refers to the end where blood flows in. For example, after a stent is implanted, blood flows from the proximal end to the distal end of the stent; "axial" refers to its length direction , "radial" means the direction perpendicular to the "axial".

The "wave ring" in the present invention is a closed wave-shaped ring structure, which can also be called a wave-shaped ring, and is made of metal elastic material weaving or cutting. The metal elastic material includes known materials or combinations of various biocompatible materials implanted in medical devices, such as alloys of two or more single metals in cobalt, chromium, nickel, titanium, magnesium, iron, and 316L stainless steel, nickel-titanium-tantalum alloy, etc., or other biocompatible metal elastic materials. The corrugated coil has the ability to expand radially, and can realize radial contraction under the action of external force, and self-expand or expand mechanically (for example, by balloon expansion) to return to the original shape and maintain the original shape after the external force is removed. After entering the lumen, it can cling to the inner wall of the lumen through its radial support force. The waveform of the wave coil is not limited, including Z-shaped wave, M-shaped wave, V-shaped wave, sine wave, etc. The wave circle includes a plurality of crests (also known as proximal vertices), a plurality of troughs (also known as distal vertices), and a wave rod connecting adjacent crests and troughs. Among them, a vertex (near end vertex or far end vertex) and two wave rods connected with this vertex form a wave.

The "wave number" referred to in the present invention refers to the number of crests or troughs, and the number of crests and troughs in the same wave circle is the same. "Wave height" refers to the vertical distance between the crest and the line connecting two adjacent troughs. "Wave angle" refers to the angle between two adjacent wave rods.

Example 1

Referring to FIG. 1 , the present embodiment exemplarily provides a stent graft 100 . The stent graft 100 includes a self-expanding tubular body 10 . The tubular body 10 is a hollow lumen structure, and the lumen of the tubular body 10 constitutes a channel for blood flow. The tubular body 10 includes an end section 1 and a main section 2 connected to the end section 1 , the end section 1 is located at the proximal end of the main section 2 , or the end section 1 is located at the distal end of the main section 2 .

Wherein, the main body section 2 includes a tubular main frame 121 and a main body coating 122 connected to the main frame 121 . The main frame 121 has the ability to expand radially, and can realize radial contraction under the action of external force, and self-expand to return to the original shape and maintain the original shape after the external force is removed, so that after implanting in the lumen, it can be tightened by its radial support force. Stick to the inner wall of the lumen. The main frame 121 is made of materials with good tensile and resilience properties and good biocompatibility, such as nickel titanium, stainless steel and other materials. In this embodiment, the main frame 121 includes a plurality of wave-shaped rings arranged axially. In other embodiments, the main body skeleton 121 may also be a mesh structure, a helical structure, etc. formed by weaving or cutting.

The main body coating 122 can be made of polytetrafluoroethylene (PTFE for short), polyethylene terephthalate (PET for short) and other polymer materials with good biocompatibility. The main body covering film 122 is fixed on the inner surface and/or outer surface of the main body framework 121 by means of suturing, bonding, hot-melting, etc., so as to reconstruct the fluid channel and isolate the diseased area of the lumen.

The end section 1 includes a tubular end coating 20 , and the end section 1 has an open end, which can be formed by surrounding the edge of the end coating 20 . Further, the end section 1 is provided with an end support assembly, wherein the end support assembly includes a first wave coil 30 and a second wave coil 40 connected to the end section 1 . Generally, the tubular body 10 has at least one proximal open end 10a and one distal open end 10b. The first wave ring 30 and the second wave ring 40 can be arranged on the end section 1 where the proximal open end 10a of the tubular body 10 is located, or the end section 1 where the distal open end 10b is located, or both can be arranged on the tubular body. The end sections 1 at both ends of the main body 10 can be selectively set according to actual needs. In this embodiment, the first wave coil 30 and the second wave coil 40 are disposed on the proximal open end 10 a of the tubular body 10 .

Please refer to FIG. 2 at the same time, the end section 1 has at least one first state and one second state. When the end section 1 is radially compressed to the first state, the end section 1 has a first radial dimension r (the radial dimension can be obtained by measuring the diameter of the circumscribed circle of the end section 1, the same below), and the first wave The loop 30 at least partially extends over the open end, forming the overrun 21 . The axial length of the jumping portion 21 is greater than 1 mm. The end section 1 has a second radial dimension R when the end section 1 is radially deployed from the first state to the second state. The end section 1 in the second state has a larger radial dimension than that in the first state, that is, the second radial dimension R is greater than the first radial dimension r, and the end section 1 at this time can be a natural The unfolded state (that is, the naturally stretched state without being subjected to artificial external force) may also be a state that has been compressed radially to a certain extent but has not yet been fully deployed. Referring to Fig. 3, when the end segment 1 is in the second state, the first wave ring 30 is located in the axial area A1 where the end segment 1 is located, and the axial area A2 where the first wave ring 30 is located is in the same direction as the second wave ring The axial area A3 in which 40 is located overlaps at least partially. When the stent-graft 100 is in the loaded state, the first wave ring 30 can be deformed and connected to the conveyor across the open end, thereby preventing the sheath from withdrawing and driving the stent-graft 100 to shift, increasing the release of the stent-graft 100 accuracy. During the release process of the stent graft 100, the first wave ring 30 deforms and retreats to the axial region where the end section 1 of the tubular body 10 is located, and the end section 1 of the tubular body 10 will form a certain shape on the first wave ring 30. The degree of restraint reduces the stimulation and damage to blood vessels during the release process of the first wave coil 30 . Since the first corrugated coil 30 is flexibly connected to the end section 1, and there is an overlapping axial area between the first corrugated coil 30 and the second corrugated coil 40, when the stent graft 100 is implanted into a blood vessel with a large degree of curvature, The first corrugated coil 30 can move relative to the end section 1 to a certain extent, so as to better adapt to the curved blood vessel, and cooperate with the second corrugated coil 40 to enhance the adherence between the end section 1 and the curved blood vessel.

In addition, in this embodiment, in order to further improve the wall-adherence of the end section 1, when the end section 1 is in the second state, the axial area A2 where the first wave coil 30 is located is located on the axis where the second wave coil 40 is located. to the area A3.

In this embodiment, the first wave ring 30 includes a first wave ring structure formed by a first support wire, and the first wave ring structure includes a plurality of substantially parallel first direction wave rods 32 and a plurality of substantially parallel The second direction probe 33, and the adjacent first direction probe 32 and the second direction probe 33 are connected with the same first wave crest 34 to form a first wave, the adjacent first direction probe 32 and the second direction probe 32 The wave rod 33 connects with a first wave trough 35 to form a second wave. The first wave ring 30 is elastically deformable. It can be partially or completely made of elastic material. For example, the first wave ring 30 can be made of materials with good tensile and resilience properties and good biocompatibility, such as nickel titanium, stainless steel and other materials. Due to its good stretching and resilience properties, it has its own elasticity to recover from deformation. Being elastically deformable, on the one hand, it can ensure that it can quickly cross the opening end and retract into the opening end during the deformation process; stability in the process. In other embodiments, the first wave coil 30 may be made of non-elastic material, for example, adjacent wave rods in the first wave coil 30 made of non-elastic material are rotationally connected by setting a pivot member. At this time, the first wave ring 30 itself has no elastic force, and its deformation is driven by the self-expanding tubular body 10 and/or the second wave ring 40 .

The second wave coil 40 includes a second wave-shaped ring structure formed by the second support wire, and has self-expanding performance. The second wave ring structure includes a plurality of substantially parallel third direction probes 42 and a plurality of substantially parallel fourth direction probes 43, and adjacent third direction probes 42 and fourth direction probes 43 are connected The same second crest 44 forms a third wave, and the adjacent third direction wave rod 42 and fourth direction wave rod 43 connect with the same second wave trough 45 to form a fourth wave. The second wave coil 40 is fixedly connected to the end section 1 and is located in the axial area A1 where the end section 1 is located. As shown in the figure, the second wave ring 40 is not only located in the axial region A1 where the end section 1 is located, but its peak is almost flush with the proximal open end 10a, so that the proximal open end 10a can better maintain its Shape, and better fit with the inner wall of the blood vessel. In addition, in this embodiment, the first crest 34 of the first wave coil 30 is located between the third wave rod 42 in the third direction and the rod 43 in the fourth direction, and between two adjacent first wave crests 34 There is a third wave, the first trough 35 of the first wave circle 30 is located between two adjacent first crests 34 , and is located in the third wave between the two adjacent first crests 34 .

The end coating 20 of the end section 1 includes an inner coating and an outer coating, the inner coating is located inside the second wave coil 40 , and the outer coating is located outside the second wave coil 40 . In this embodiment, the second wave coil 40 is fixedly connected between the inner coating and the outer coating. For example, both the outer coating and the inner coating are made of PTFE, and the inner coating and the outer coating are bonded to each other by hot melting to wrap and fix the second wave coil 40 therebetween. In other embodiments, the inner coating and the outer coating can also be fixedly connected to the second corrugated ring 40 by means of bonding, sewing or the like.

The second wave coil 40 includes an inner film-coated segment 46 and an inner exposed segment 47 . Wherein, the outer surface of the inner layer film section 46 is covered with an outer layer film, and its inner surface is covered with an inner layer film, while the inner surface of the inner layer exposed section 47 is not covered with an inner layer film, and only the outer surface is covered with an outer layer film. film, and a gap is formed between the exposed section 47 of the inner layer and the outer coating film. Please refer to Fig. 4 at the same time, both ends of the inner layer exposed section 47 are connected to the inner layer film section 46, the inner layer exposed section 47, the outer layer film, and the inner layer film covered by the inner surface of the inner layer film section 46 are common Enclosed to form a limit channel 22, the width W of the limit channel 22 (along the length direction of the wave rod of the second wave coil 40, the size of the limit channel 22) does not exceed 1/3 of the length of the wave rod of the second wave coil 40 . The first support wire of the first wave coil 30 can slide through the limiting channel 22 to be flexibly connected with the second wave coil 40 and the end coating 20 .

In this embodiment, the plurality of limiting passages 22 are uniformly arranged at intervals in the circumferential direction, and the plurality of limiting passages 22 are roughly located on the same radial plane (a plane perpendicular to the axis). The first direction probes 32 of the first wave coil 30 pass through the corresponding limiting passages 22 , while the second direction probes 33 do not pass through the limiting passages 22 . The advantage of this arrangement is that the plurality of limiting channels 22 form uniform constraints on the first wave coil 30 in the circumferential direction, no matter what state it is in, the first wave coil 30 can be relatively stably connected to the end section 1, It is not easy to come out; in addition, because only the first direction wave rod 32 in the first wave coil 30 passes through the corresponding limiting channel 22, and the second direction wave rod 33 is not bound by the limiting channel 22, so the first wave The ring 30 can move more flexibly in the axial direction of the end section 1, so that the end section 1 can fit the curved inner wall of the blood vessel better. In other embodiments, the second directional probes 33 of the first wave coil all pass through the corresponding limiting passages 22 , while the first directional probes 32 do not pass through the limiting passages 22 .

It should be noted that in the process of compressing the tubular body 10, the tubular body 10 will also be stretched to a certain extent due to compression, so the first corrugated ring 30 provided at the opening end of the tubular body 10 can be compressed under pressure. At least partly crossing the open end, it is necessary to ensure that the axial elongation of the first wave ring 30 is greater than the axial elongation of the end section 1 and the first wave ring The sum of the distances from the crest to the end of the opening is 30. Exemplarily, a feasible way to achieve this purpose is to arrange the first wave coil 30 close to the end of the opening. For example, in the naturally unfolded state, the peak of the first wave ring 30 is flush with or slightly lower than the opening end of the tubular body 10. This method can effectively reduce the distance between the peak of the first wave ring 30 and the opening end. distance, thereby reducing the requirement on the elongation of the first wave coil 30, and making it easier for the first wave coil 30 to pass over the opening end. It can be understood that the wave rod length of the first wave coil 30 is greater than or equal to the wave rod length of the second wave coil 40, and the wave angle of the first wave coil 30 is greater than the wave angle of the second wave coil 40, this way can make When under pressure, the first wave ring 30 may have a longer elongation in the axial direction than the tubular body 10, so as to ensure that it can pass over the open end. It should be noted that the axial elongation or axial elongation in this embodiment refers to the axial growth of the first wave ring 30 and the end section 1 due to pressure when they are inserted into the sheath. The amount, that is, the difference between the axial length under pressure and the axial length in the natural state; the axial length refers to the distance between the proximal end and the distal end of the first wave ring 30 or the corrugated tubular body in the axial direction. It is understandable that the above-mentioned method is only an example and is not limited thereto, as long as it can be realized that the extension length of the wave rod of the first wave coil 30 is greater than that of the end section 1 when it is compressed and close to a nearly parallel shape. The sum of the length and the distance from the crest of the first wave ring 30 to the opening end is sufficient. However, one of the above methods can be selected for setting, and multiple methods can also be combined for setting, depending on the specific needs. In addition, in other embodiments, if the first wave coil 30 cannot automatically pass over the opening end when it is pressed, as long as the first wave coil 30 that is movably connected with the end section 1 can receive the axial direction towards the opening end Under the action of force, it moves toward the opening end and crosses the opening end, which can also achieve the purpose of the present invention.

Furthermore, for the solution that the limiting channel 22 only constrains one of the first direction wave rod 32 and the second direction wave rod 33, in order to ensure that the first wave coil 30 can be completely retracted to the end In the axial region of the section 1 , at least one limiting channel 22 may be provided with a shortest distance from the proximal opening end 10 a greater than or equal to the wave height of the first wave ring 30 .

Example 2

On the basis of Embodiment 1, this embodiment specifically proposes another setting method of the limiting channel 22 . Referring to FIG. 5 , each first wave type of the first wave coil 30 has a wave rod passing through the corresponding limiting channel 22 . For example, in a certain first wave, the first direction probe 32 passes through the first limiting channel 22a, and the second direction probe 33 of the wave passes through the second limiting channel 22b, wherein the first limiting channel 22a and the second limiting channel 22b are arranged at intervals, and the proximal end point of the first limiting channel 22a and the proximal end point of the second limiting channel 22b are basically located on the same radial plane, and the proximal end point of the first limiting channel 22a The distance between it and the proximal end point of the second limiting channel 22b is d. The distance from the proximal end point of the first limiting channel 22a to the proximal opening end 10a and the distance from the proximal end point of the second limiting channel 22b to the proximal opening end 10a are approximately equal, both being h. The wave angle α of the first wave circle 30 should satisfy the following relationship:

Wherein, the above units of d and h are the same, for example, the units are millimeters. When the wave angle α of the first wave coil satisfies the above relationship, it can be ensured that the first wave coil 30 is completely retracted into the axial region of the end section 1 when the end section 1 is naturally deployed. It can be understood that, in other embodiments, the proximal end points of the first limiting channel 22a and the second limiting channel 22b and the proximal end point of the second limiting channel 22b may be located on different radial planes, the first The wave angle of the wave coil 30 can also be specifically set according to specific application scenarios, but no matter how the proximal end point of the limiting channel 22 and the wave angle of the first wave coil 30 are set, at least ensure that the first wave coil 30 is at the end section 1 is completely retracted into the axial region of the end section 1 in a naturally unfolded state.

Further, in order to ensure that the first wave coil 30 is located in the axial region of the second wave coil 40 in the naturally unfolded state of the end section 1, the wave angle α of the first wave coil 30 should also satisfy the following relationship:

Wherein, the distance between the distal end point of the first limiting channel 22a and the distal end point of the second limiting channel 22b is D. The axial distance from the distal end point of the first limiting channel 22a to the wave trough of the second wave ring 40 and the axial distance from the distal end point of the second limiting channel 22b to the wave trough of the second wave ring 40 are approximately equal, both The units of H, D and H are the same, for example, the units are all millimeters.

It can be understood that, in other embodiments, the distal end points of the first limiting channel 22a and the second limiting channel 22b and the distal end point of the second limiting channel 22b may be located on different radial planes, the first The wave angle of the wave coil 30 can also be specifically set according to specific application scenarios, but no matter how to set the far end point of the limiting channel 22 and the wave angle of the first wave coil 30, at least ensure that the first wave coil 30 is at the end section 1 Located in the axial region of the second wave ring 40 in a naturally unfolded state.

In this embodiment, since each first direction wave rod 32 and second direction wave rod 33 of the first wave coil 30 pass through the corresponding limiting channel 22, the first wave coil 30 can be better restrained in the axial direction. The above range of motion further ensures that the first wave ring 30 returns to the axial region of the second wave ring 40 during the expansion process of the end section 1 .

Example 3

Referring to FIG. 6 , on the basis of Embodiment 1 and Embodiment 2, the stent graft 100 of this embodiment further includes a movable connector, through which the first wave coil 30 is flexibly connected to the end section 1 . The movable connecting part includes an elongated connecting part 51 , one end of which is connected to the first wave coil 30 , and the other end is connected to the inner exposed section 47 of the second wave coil 40 .

In this embodiment, each first wave trough 35 in the first wave coil 30 is respectively connected to the inner layer exposed sections 47 (see FIG. 3 ) on both sides of the first wave trough 35 through two elongated connecting pieces 51, each One end of the elongated connecting member 51 is fixedly connected to the first wave trough 35 of the first wave coil 30 , and the other end is fixedly connected to the exposed inner layer section 47 of the second wave coil 40 . The elongated connecting piece 51 is made of flexible soft material, such as a rod, wire, thread, etc. formed of soft polymer material, inorganic material or flexible metal, or the like. The fixed connection method between the elongated connecting member 51 and the first wave coil 30 or the second wave coil 40 includes one or more of adhesion, sewing, welding, entanglement, and heat fusion.

The movable joint of this embodiment can limit the axial range of motion of the first wave ring 30 within a certain range, so the axial range of motion of the first wave ring 30 can be better restricted, by adjusting the length of the flexible joint and position, can ensure that the first wave ring 30 returns to the axial region of the end section 1 during the expansion process of the end section 1, and can further ensure that the first wave ring 30 returns to the first wave ring 30 during the expansion process of the end section 1 In the axial area of the second wave coil 40, there is no need to restrict too much setting of parameters such as the position and size of the limiting channel 22 (see FIG. 4 ), the wave angle and wave height of the first wave coil 30 . In other embodiments, if a movable link is provided, the limiting channel 22 in Embodiments 1 and 2 can be omitted, and the movable link can simultaneously play the role of connection and limit.

In other embodiments, the connection position of the elongated connecting member 51 may be different. As shown in FIG. 7 , one end of the elongated connecting member 51 is fixedly connected with the first wave valley 35 of the first wave coil 30 , and the other end is fixedly connected with the second wave valley 45 of the second wave coil 40 . As shown in FIG. 8 , one end of the elongated connecting member 51 is fixedly connected with the first direction wave rod 32 and the second direction wave rod 33 of the first wave coil 30 , and the other end is connected with the second wave crest 44 on the second wave coil 40 Fixed connection.

In other embodiments, the above-mentioned elongated connector 51 can also be flexibly connected with the first wave coil 30 and the second wave coil 40, for example, the end of the elongated connector 51 is provided with a movable collar or a movable sleeve, etc. The movable part is movably connected between the movable part and the first wave ring 30 and the second wave ring 40, so that the end of the elongated connecting part 51 can slide along the first support wire of the first wave ring 30, and/or, The end of the elongated connecting member 51 can slide along the second support wire of the second wave coil 40 . The advantage of this arrangement is that the first corrugated coil 30 can move more flexibly relative to the end section 1 , and can better adjust its position to adapt to the shape of the curved blood vessel, so that the end section 1 can better fit the inner wall of the blood vessel.

It can be understood that in other embodiments, the number of elongated connecting pieces 51 may also be different from this embodiment, for example, each first wave trough 35 in the first wave coil 30 is respectively connected to the On the exposed inner layer section 47 on both sides of the first wave trough 35, and each first crest 34 in the first wave coil 30 is respectively connected to the exposed inner layer on both sides of the first wave crest 34 through two elongated connecting pieces 51. Paragraph 47 above. The advantage of such setting is that the first wave coil 30 can be more stably connected to the second wave coil 40 and prevent the first wave coil 30 from turning over.

Further, this embodiment also provides another kind of movable connection, and the first wave coil 30 is movably connected with the end section 1 through the movable connection. The movable connecting part includes an elongated connecting part 51 , one end of which is connected to the first wave coil 30 , and the other end is connected to the inner exposed section 47 of the second wave coil 40 .

In this embodiment, each first wave crest 34 in the first wave coil 30 is respectively connected to the exposed inner layer sections 47 on both sides of the first wave crest 34 through two elongated connecting pieces 51 . The elongated connecting piece 51 is made of hard material, for example, the elongated connecting piece 51 can be a rod-shaped structure made of hard metal, hard polymer material and the like.

One end of the elongated connecting member 51 is fixedly connected to the first crest 34 of the first wave coil 30 , and the fixed connection method includes one or more of bonding, sewing, welding, entanglement, and thermal fusion. The other end is movably connected with the exposed inner layer section 47 on the second wave coil 40 through a movable part. The movable part includes one or more of a movable collar and a movable sleeve. The movable part is movably sleeved on the exposed inner layer section 47 and is fixedly connected with the end of the elongated connecting part 51 . Since the movable part can slide on the exposed inner section 47 , the first wave ring 30 connected thereto can move axially relative to the end section 1 and the second wave ring 40 .

The slender connecting piece 51 of this embodiment is made of hard material. During the expansion process of the end section 1, as the second wave coil 40 can drive the first wave coil 30 to retract through the slender connecting piece 51, the The first wave coil 30 recovers more rapidly in the axial region of the end section 1 during the expansion of the end section 1 . In addition, the elongated connecting piece 51 made of hard material can provide a radially outward supporting force for the end coating 20 , which can further improve the wall-attachment performance of the end section 1 .

In other embodiments, the connecting positions of the elongated connecting member 51 and the movable member may be different. As shown in the figure, the first trough 35 of the first wave ring includes an arc structure, and the movable part is sleeved on the arc structure of the first wave trough 35 in the first wave ring 30, and can slide along the arc structure, elongated One end of the connecting member 51 is fixedly connected to the movable member, and the other end is fixedly connected to the second wave trough 45 on the second wave coil 40 .

Example 4

Referring to FIG. 9 , this embodiment exemplarily provides a stent-graft delivery system, which includes a stent-graft 100 and a transporter 200 . For the specific structure of the stent graft 100, reference may be made to Examples 1-3. The conveyor 200 is used to deliver the stent graft 100. The conveyor 200 includes a sheath core 201 and a sheath tube 202. The stent graft 100 is compressed and accommodated between the sheath core 201 and the sheath tube 202. The sheath core 201 is provided with an anchor Section 201a. When the stent graft 100 is radially compressed and loaded in the sheath tube 202 of the conveyor 200, the anchoring portion 201a of the sheath core 201 is connected to the first corrugated coil 30 that crosses the opening end, that is, the anchoring portion 201a is connected to the crossing portion 21 connections.

Referring to FIG. 1 , when the tubular body 10 in the stent graft 100 of the present embodiment is in a naturally expanded state, the first coil 30 does not pass over the proximal opening end 10 a of the tubular body 10 . During assembly, as shown in FIG. 2 , the tubular body 10 in a naturally unfolded state is radially compressed when subjected to a radial external force. At this time, the first wave ring 30 is compressed with the tubular body 10 under radial pressure. Moreover, the poles of the first wave coil 30 are close to each other, so that the first wave coil 30 protrudes from the proximal open end 10 a to form the crossing portion 21 . Further, as shown in FIG. 9, the stent graft 100 is connected to the sheath core 201 and loaded into the sheath tube 202. At this time, the anchoring portion 201a of the sheath core 201 is connected to the crossing portion 21, and the sheath tube 202 is withdrawn ( When the sheath is retracted toward the direction away from the proximal open end 10a), since the first wave coil 30 is connected to the sheath core 201, and the sheath core 201 provides axial support, the stent graft 100 remains still, and as the Withdrawal of the sheath 202. When released, the tubular body 10 self-expands under the action of its own resilience or is driven by the tubular body 10 to expand. At this time, the wave rods of the first wave ring 30 move away from each other and make the first wave ring 30 return to the end of the tubular body 10 Segment 1, overhang 21 disappears.

The stent-graft delivery system of this embodiment can not only release the self-expandable stent-graft quickly, efficiently and accurately, but also because the stent-graft is only connected to the sheath core 201 through the first wave coil 30, during the release process It can prevent the sheath tube from retreating to drive the stent graft 100 to shift, increasing the accuracy of the release of the stent graft 100; in addition, during the release process of the stent graft 100, the first wave coil 30 is deformed and retracted to the center of the tubular main body 10. In the axial region where the end section 1 is located, the end section 1 of the tubular body 10 forms a certain degree of restraint on the first wave coil 30 , reducing the irritation and damage to the blood vessel during the release process of the first wave coil 30 .

The technical features of the above-mentioned embodiments can be combined arbitrarily. To make the description concise, all possible combinations of the technical features in the above-mentioned embodiments are not described. However, as long as there is no contradiction in the combination of these technical features, should be considered as within the scope of this specification.

The above-mentioned embodiments only express several implementation modes of the present invention, and the descriptions thereof are relatively specific and detailed, but should not be construed as limiting the patent scope of the invention. It should be noted that, for those skilled in the art, several modifications and improvements can be made without departing from the concept of the present invention, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the patent for the present invention should be based on the appended claims.

Claims (13)

1. The covered stent, is characterized in that, comprising: a self-expanding tubular body comprising an end section having an open end; a deformable first wave ring, the first wave ring is movably connected with the end section; a second wave coil connected to the end segment; When the end section is radially compressed to a first state, the first wave coil can at least partially pass over the open end, and when the end section is radially expanded from the first state to a second state, the first wave coil is located in the axial region where the end section is located, and the axial area where the first wave coil is located overlaps at least partially with the axial area where the second wave coil is located. 2. The stent graft according to claim 1, wherein when the end section is in the second state, the axial region where the first wave ring is located is located on the axis where the second wave ring is located into the area. 3. The stent graft according to claim 1, wherein the second wave coil is fixedly connected to the end section, and the second wave coil is located in the axial region where the end section is located Inside. 4. The stent graft according to claim 1, wherein the end section comprises an end coating, and when the end section is in the second state, the end coating covers the first The outer surface of the second wave ring and the first wave ring. 5. The stent graft according to claim 4, wherein the end coating comprises an outer coating, and the outer coating is located outside the second corrugated coil, and the second corrugated coil The ring includes a bare inner section, the inner surface of the exposed inner section is exposed, and the first corrugated coil is connected to the second corrugated coil through the exposed inner section. 6. The stent graft according to claim 5, wherein at least one limiting channel is provided between the second corrugated coil and the outer coating, and the first corrugated coil consists of a first The support wire forms a wave-shaped ring structure, and the first support wire passes through the limiting channel, so that the first wave ring is movably connected to the end section. 7. The stent graft according to claim 6, wherein the end coating further comprises an inner coating, the second wave coil further comprises an inner coating segment, and the inner coating The inner surface of the section is covered with the inner film, and both ends of the exposed inner section are connected to the inner film section, the exposed inner section, the outer film, and the inner film section The surface-covered inner film surrounds and forms the position-limiting channel. 8. The stent-graft according to claim 1, wherein the stent-graft further comprises a movable connector, the first wave coil is connected to the end section through the movable connector, and the The first wave ring is movable relative to the end section in the axial direction. 9. The stent graft according to claim 8, characterized in that, the movable connector comprises an elongated connector, one end of the elongated connector is connected to the first wave coil, and the other end is connected to the inner coil. The exposed sections of the layers are connected, and at least one end of the elongated connecting piece is a fixed connection end. 10. The stent graft according to claim 9, wherein the first wave coil comprises a plurality of first wave valleys and first wave crests, and the first wave valleys are respectively connected to the and/or, the first crest is respectively connected to the exposed inner layer segments on both sides of the first crest through two elongated connectors. 11. The stent graft according to claim 9, wherein the first wave coil comprises a plurality of first wave troughs and a plurality of wave bars, and the second wave coil comprises a plurality of second wave peaks and a plurality of The second wave trough, the first wave trough is connected to the second wave trough on both sides of the first wave trough through two elongated connecting pieces; and/or, the second wave crest is respectively connected through two elongated connecting pieces to the wave rods of the first wave coil located on both sides of the second wave crest. 12. The stent graft according to claim 1, wherein the wave angle of the second wave coil is smaller than the wave angle of the first wave coil, and the wave bar of the second wave coil is less than or equal to The pole of the first wave. 13. A stent-graft delivery system, characterized in that it comprises a conveyor and the stent-graft according to any one of claims 1 to 12, the conveyor is used to deliver the stent-graft, and the conveyor It includes a sheath core, the distal end of the sheath core is provided with an anchoring part, and when the stent-graft is loaded in the conveyor, the anchoring part and the first corrugated coil passing over the open end connect.

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