Interventional device for chronic internal carotid artery occlusion

Abstract

The invention provides an intervention device for chronic internal carotid artery occlusion, and relates to the technical field of medical instruments.The intervention device comprises an outer-layer support, an inner-layer support and a pushing guide wire, and the outer-layer support and the inner-layer support both have a pressing and holding state and an expansion state; in the pressing and holding state, the outer-layer stent and the inner-layer stent are arranged in the circumferential direction of the pushing guide wire and are pressed and held in the sheathing canal, and the outer-layer stent is located at the far end of the inner-layer stent; the far end of the inner-layer stent is connected with the near end of the outer-layer stent through a plurality of silk threads; a first pushing part and a second pushing part are arranged at the far end of the pushing guide wire and are respectively used for pushing the outer-layer stent and the inner-layer stent out of the sheathing canal. The interventional device provided by the invention has a double-conveying structure, can release the outer-layer stent firstly and then release the inner-layer stent at the high-risk plaque position, so that the high-risk plaque area is protected emphatically, and the problems that an existing carotid artery stent cannot control plaque escape in an occluded area and the like are solved.

Description

Technical Field

[0001] The invention belongs to the technical field of medical devices, and in particular relates to an interventional device for chronic occlusion of the internal carotid artery. Background Art

[0002] Internal carotid artery occlusion (ICAO) is one of the important factors leading to ischemic stroke. According to the severity of the onset, it can be divided into acute internal carotid artery occlusion (AICAO) and chronic internal carotid artery occlusion (CICAO). Usually, occlusion lasting more than 4 weeks is classified as CICAO, and occlusion lasting less than 1 week is classified as AICAO. Commonly used treatments for chronic internal carotid artery occlusion in clinical practice include drug therapy, vascular reconstruction, and vascular recanalization.

[0003] Plaques in the carotid artery start from the early stage, that is, after the plaque grows, the internal carotid artery changes from mild stenosis, moderate stenosis to severe stenosis. When it becomes severe, it will cause changes in distal blood flow, or the detachment of plaques will cause distal embolism, so vascular stents are generally selected for vascular opening. In clinical practice, some patients will slowly occlude their blood vessels during the process of internal carotid artery stenosis. After occlusion, the clinical symptoms are not severe through compensation by other collateral circulation and adjacent blood vessels. For such cases, stents can also be used to open the chronic occlusion of the internal carotid artery. The internal carotid artery plaque is mainly composed of lipid components, surrounded by fibrous tissue, forming a bulge on the arterial wall. Moreover, it has been clinically confirmed that about 25% to 30% of cerebral infarctions are related to carotid artery plaques, especially some middle-aged and elderly groups, or people with underlying diseases, such as hypertension, hyperlipidemia, diabetes and obesity, are all high-risk groups for carotid artery plaques. The low-echo plaques that appear under medical equipment are unstable plaques, also known as high-risk plaques. These plaques have an uneven surface, irregular shape, and are prone to rupture. Ruptured plaques flow into the brain with blood, causing blockage of intracranial blood vessels and causing strokes.

[0004] Existing stents are divided into open-loop stents and closed-loop stents. The open-loop stent has good compliance and can still perfectly adhere to the wall of tortuous blood vessels. In addition, it has strong radial support force, so it is widely used in the treatment of internal carotid artery occlusion. However, compared with closed-loop stents, its disadvantage is that the mesh is larger and the metal coverage is low. Existing internal carotid artery stents are mostly single-layer open-loop structures. At least the following technical problems are caused:

[0005] (1) When existing stents have mesh holes covering the occluded area, when they are attached to the surface of the plaque, the stent itself will cut the plaque, causing the plaque to escape from the mesh holes of the stent. Then, the plaque will float into the brain along with the blood flow in the lumen, causing a stroke.

[0006] (ii) The existing vascular stents have a low metal coverage rate and cannot provide better support for the growth of vascular endothelium, thus affecting the repair effect of vascular endothelium.

[0007] (III) The location of high-risk plaques in the occluded area of ​​the carotid artery is random, and the clinical manifestation is that the location of high-risk plaques in the occluded area is different in different patients. The existing single-layer stent cannot solve the problem of targeted protection of high-risk plaque areas.

[0008] Therefore, the present invention provides an interventional device for chronic occlusion of the internal carotid artery to solve the deficiencies in the prior art. Summary of the invention

[0009] The purpose of the present invention is to provide an interventional device for chronic occlusion of the internal carotid artery, which can strengthen the protection of high-risk plaque areas after supporting the occluded area of ​​the carotid artery under the development of medical equipment during the operation, so as to solve the problems that the existing carotid stent cannot control the escape of plaques in the occluded area and cannot focus on protecting the high-risk plaque area.

[0010] In order to achieve the above object, the present invention provides the following technical solutions:

[0011] An interventional device for chronic occlusion of the internal carotid artery, comprising an outer stent, an inner stent and a push guide wire, wherein the outer stent and the inner stent both have a compression state and an expansion state;

[0012] When in the pressed and gripped state, the outer layer stent and the inner layer stent are circumferentially arranged around the pushing guide wire and pressed and gripped in the sheath, and the outer layer stent is located at the distal end of the inner layer stent;

[0013] The distal end of the inner stent is connected to the proximal end of the outer stent via a plurality of silk threads;

[0014] The distal end of the pushing guide wire is provided with a first pushing portion and a second pushing portion, wherein the first pushing portion is used to push the outer layer stent out of the sheath tube, and the second pushing portion is used to push the inner layer stent out of the sheath tube.

[0015] Preferably, a first spring is arranged around the outer side of the first pushing portion, and the first spring is used to push the outer layer bracket; a second spring is arranged around the outer side of the second pushing portion, and the second spring is used to push the inner layer bracket.

[0016] Preferably, the first pushing portion and the second pushing portion are both conical, and the diameters of the first pushing portion and the second pushing portion gradually decrease toward the distal direction.

[0017] Preferably, when in the pressed and gripped state, the outer layer support and the inner layer support are separated by the first pushing portion.

[0018] Preferably, a buckle is provided at the distal end of the first pushing portion and / or the second pushing portion, and the buckle is used to prevent the outer layer support and / or the inner layer support from moving toward the distal direction.

[0019] Preferably, a first developing portion is provided at the distal end of the first pushing portion, and when in the pressed and gripped state, the first developing portion is located on the inner side of the outer layer support.

[0020] Preferably, a second developing portion is provided between the first pushing portion and the second pushing portion, and when in the pressed and gripped state, the second developing portion is located on the inner side of the inner layer support.

[0021] Preferably, the surface of the outer layer stent and / or the inner layer stent is provided with an anti-stenosis coating.

[0022] Preferably, the outer layer stent is an open-loop stent.

[0023] Preferably, the inner layer stent is a closed-loop stent, and the mesh density of the inner layer stent is greater than the mesh density of the outer layer stent.

[0024] Beneficial effects:

[0025] (1) The stent provided by the present invention is a double-layer stent having an inner stent and an outer stent. The outer stent adopts an open-loop stent with good support and wall adhesion, and the inner stent adopts a closed-loop stent with high metal coverage and denser mesh, thereby reducing the risk of plaque escaping from the stent mesh in the occluded area of ​​the internal carotid artery after the stent is released.

[0026] (2) The interventional device provided by the present invention includes a push guide wire matched with a double-layer stent. The push guide wire has a double delivery structure. Under the development of clinical surgical medical equipment, the outer stent is released first, and then the inner stent is released at the high-position plaque according to the position of the high-risk plaque. In this way, the high-risk plaque area is protected and the risk of high-risk plaque rupture is reduced.

[0027] (3) Provide better support for the growth of vascular endothelium in the chronic occlusion area of ​​the internal carotid artery, facilitate the repair of vascular endothelium, and reduce the patient's recovery time. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] The drawings constituting a part of the present application are used to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. Among them:

[0029] Figure 1 It is a schematic structural diagram of a double-layer stent in a compressed and gripped state according to an embodiment of the present invention.

[0030] Figure 2 This is a schematic diagram of a push guide wire and a sheath according to an embodiment of the present invention.

[0031] Figure 3 The figure is a schematic structural diagram of a push guide wire according to an embodiment of the present invention.

[0032] Figure 4 The figure is a schematic diagram of the structure of an outer layer support according to an embodiment of the present invention.

[0033] Figure 5 The figure is a schematic structural diagram of an inner layer support according to an embodiment of the present invention.

[0034] Figure 6 This is a schematic diagram of an outer layer support when released according to an embodiment of the present invention.

[0035] Figure 7 This is a schematic diagram of an inner layer stent being released according to an embodiment of the present invention.

[0036] Figure 8 This is a schematic diagram of withdrawing the push guide wire and sheath after releasing the double-layer stent according to an embodiment of the present invention.

[0037] Fig. 9 This is a schematic diagram of an outer layer stent and an inner layer stent before being pressed into the sheath tube according to an embodiment of the present invention.

[0038] Fig.10 This is a schematic diagram of a double-layer stent after release according to an embodiment of the present invention.

[0039] In the figure: 100, outer layer stent; 200, inner layer stent; 300, push guide wire; 400, sheath; 301, first push part; 302, second push part; 303, first spring; 304, second spring; 305, buckle; 306, first developing part; 307, second developing part. DETAILED DESCRIPTION

[0040] The technical solutions in the embodiments of the present invention are described clearly and completely below. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. All other embodiments obtained by ordinary technicians in this field based on the embodiments of the present invention belong to the scope of protection of the present invention.

[0041] In the description of the present invention, it should be understood that descriptions involving orientations, such as up, down, front, back, left, right, etc., and orientations or positional relationships indicated are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present invention.

[0042] In the description of the present invention, "several" means one or more, "more" means more than two, "greater than", "less than", "exceed" etc. are understood as not including the number itself, and "above", "below", "within" etc. are understood as including the number itself. If there is a description of "first" or "second", it is only used for the purpose of distinguishing the technical features, and cannot be understood as indicating or implying the relative importance or implicitly indicating the number of the indicated technical features or implicitly indicating the order of the indicated technical features.

[0043] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, the features defined as "first" and "second" may explicitly or implicitly include one or more features.

[0044] In the description of the present invention, it should be noted that, unless otherwise clearly stipulated and limited, the term "connection" should be understood in a broad sense. For example, it can be a fixed connection or a movable connection, a detachable connection or a non-detachable connection, or an integral connection; it can be a mechanical connection, an electrical connection, or mutual communication; it can be a direct connection, or an indirect connection through an intermediate medium, and it can be internal connection between two elements, indirect connection, or an interactive relationship between two elements.

[0045] In the description of the present invention, the "proximal end" is the end close to the operator, and the "distal end" is the end away from the operator. For ease of understanding, unless otherwise specified, the right side of the drawings in the specification of the present invention is the "distal end" direction, and the left side is the "proximal end" direction.

[0046] The present invention will be described in detail below in conjunction with embodiments. It should be noted that the embodiments and features in the embodiments of the present invention can be combined with each other without conflict.

[0047] The present invention aims to solve the problem that the metal coverage rate of the current internal carotid artery stent is low and the high-risk plaque cannot be specifically enhanced for protection, and provides an interventional device for chronic occlusion of the internal carotid artery.

[0048] According to one embodiment of the present invention, referring to Figures 1 to 3The interventional device for chronic occlusion of the internal carotid artery includes an outer stent 100, an inner stent 200 and a push guide wire 300. Both the outer stent 100 and the inner stent 200 have a gripping state and an expanded state. The outer stent 100 and the inner stent 200 are self-expanding stents made of materials in the prior art, such as nickel-titanium alloy and nickel-cobalt alloy. The interventional device also includes a push rod and a sheath 400. When the inner stent 200 and the outer stent 100 are in the gripping state, the outer stent 100 and the inner stent 200 are circumferentially arranged around the push guide wire 300 and gripped in the sheath 400, and the outer stent 100 is located at the distal end of the inner stent 200. In one embodiment, the outer stent 100 is located at the distal end of the inner stent 200, that is, the proximal end of the outer stent 100 and the distal end of the inner stent 200 have no overlapping portion when they are gripped in the sheath 400 ( Figure 1 As shown in the figure), in another embodiment, the outer stent 100 is located at the distal end of the inner stent 200, but the proximal end of the outer stent 100 and the distal end of the inner stent 200 partially overlap when they are pressed and gripped in the sheath 400 (not shown in the figure). As long as other positional relationships do not affect the release sequence of the outer stent 100 and the inner stent 200, they are also within the protection scope of the present invention.

[0049] According to one embodiment of the present invention, the inner stent 200 adopts a closed-loop stent with high metal coverage, and the outer stent 100 adopts an outer stent 100 with relatively good support performance, in order to avoid the inner stent 200 from drifting in the blood vessel, the drift phenomenon refers to the phenomenon that the inner stent 200 becomes insufficient in support over time, accompanied by blood flow impact, and the position moves or escapes to the distal end, which is called drift. The distal end of the inner stent 200 is connected to the proximal end of the outer stent 100 by multiple silk threads. In one embodiment of the present invention, the silk threads are metal silk threads, and the number is two or more (for example, it can be 2, 3, 4, 5, 6, 7, 8, 10, etc.). In another embodiment, the silk threads are elastic metal silk threads or elastic non-metallic silk threads. The elastic silk threads have a shorter length and better extensibility when the stent is pressed and delivered, which can reduce the occurrence of silk thread knotting. In one embodiment of the present invention, the silk threads are connected to the inner stent 200 and the outer stent 100 by welding, bonding or integral molding.

[0050] According to one embodiment of the present invention, referring to Figure 2 and Figure 3The distal end of the push guide wire 300 is provided with a first push part 301 and a second push part 302. The first push part 301 is used to push the outer layer stent 100 out of the sheath tube 400, and the second push part 302 is used to push the inner layer stent 200 out of the sheath tube 400. There is a distance interval between the first push part 301 and the second push part 302. The distance interval can be adjusted according to the length of the chronic occlusion area of ​​the internal carotid artery of the patient in clinical practice, so as to better adapt to different lesion areas and better release the stent. The first spring 303 is arranged around the outer side of the first push part 301, and the first spring 303 is used to push the outer layer stent 100; the second spring 304 is arranged around the outer side of the second push part 302, and the second spring 304 is used to push the inner layer stent 200. The first spring 303 and the second spring 304 are used for the stent to press the first push part 301 and the second push part 302 on the push rod to better pass through the tortuous part of the blood vessel and reduce damage to the stent.

[0051] In one embodiment of the present invention, the first pushing portion 301 and the second pushing portion 302 are both conical, and the diameters of the first pushing portion 301 and the second pushing portion 302 gradually decrease toward the distal end, so as to provide a support force from the proximal end to the distal end along the axis of the pushing rod. In another embodiment, the first pushing portion 301 and the second pushing portion are conical at the distal end and cylindrical at the proximal end. In one embodiment, the first pushing portion 301 and the second pushing portion 302 are ellipsoidal. As long as the structure can provide axial support force, it is within the protection scope of the present invention.

[0052] According to one embodiment of the present invention, when in the crimping state, the outer stent 100 and the inner stent 200 are separated by the first pushing portion 301 , that is, the proximal end of the outer stent 100 does not contact the distal end of the inner stent 200 .

[0053] According to one embodiment of the present invention, referring to Figures 4 to 10 , the first pushing part 301 and / or the second pushing part 302 are provided with a buckle 305 at the distal end, and the buckle 305 is used to prevent the outer stent 100 and / or the inner stent 200 from moving in the distal direction. In one embodiment, the first pushing part 301 and the second pushing part 302 are both provided with a buckle 305 at the distal end, and the buckle 305 prevents the inner stent 200 and the outer stent 100 from moving in the distal direction at the same time; in another embodiment, the first pushing part 301 is provided with a buckle 305 at the distal end, and the second pushing part 302 is not provided with a buckle 305 at the distal end. At this time, the buckle 305 prevents the outer stent 100 from moving in the distal direction. In another embodiment, the second pushing part 302 is provided with a buckle 305 at the distal end, and the first pushing part 301 is not provided with a buckle 305 at the distal end. At this time, the buckle 305 prevents the inner stent 200 from moving in the distal direction.

[0054] According to one embodiment of the present invention, a first developing portion 306 is provided at the distal end of the first pushing portion 301. When in a clamping state, the first developing portion 306 is located inside the outer layer support 100 so as to judge the position of the outer layer support 100 under medical imaging equipment.

[0055] According to one embodiment of the present invention, a second developing portion 307 is provided between the first pushing portion 301 and the second pushing portion 302. When in a clamping state, the second developing portion 307 is located on the inner side of the inner layer stent 200, so that during surgery, under the development of medical equipment, it is possible to observe whether the inner layer stent 200 reaches the high-risk plaque area.

[0056] According to one embodiment of the present invention, the surfaces of the outer stent 100 and the inner stent 200 are both provided with anti-stenosis coatings. The anti-stenosis drug coating on the inner stent 200 can release drugs in high-risk plaque areas. The anti-stenosis drug coating adopts conventional coatings in the prior art.

[0057] According to one embodiment of the present invention, referring to Figure 4 and Figure 5 The outer stent 100 is an open-loop stent, the inner stent 200 is a closed-loop stent, and the mesh density of the inner stent 200 is greater than that of the outer stent 100. The open-loop stent has good compliance and can still perfectly adhere to the wall of tortuous blood vessels. In addition, it has strong radial support force, so it is widely used in the treatment of internal carotid artery occlusion. However, compared with the closed-loop stent, its disadvantage is that the mesh is larger and the metal coverage is low. The combination of the open-loop stent and the closed-loop stent in this embodiment can enhance the protection of high-risk plaque areas.

[0058] According to one embodiment of the present invention, referring to Figure 6 to Figure 7 In actual use, under medical imaging equipment, the outer stent 100 is released first. After the outer stent 100 is released in place, the pushing guide wire 300 is continued to be pushed according to the area of ​​high-risk plaque in the image to release the inner stent 200, so that the inner stent 200 covers the high-risk plaque area. After being released in place, the pushing guide wire 300 and the sheath 400 are withdrawn to complete the release of the double-layer stent.

[0059] In summary:

[0060] (1) The present invention provides a double-layer stent, and the position of the inner layer stent 200 can be adjusted in real time according to the high-risk plaque area during surgery to increase the treatment and protection of high-risk plaques.

[0061] (2) The stent provided by the present invention is a double-layer stent having an inner stent 200 and an outer stent 100. The outer stent 100 adopts an open-loop stent with good support and wall adhesion, and the inner stent 200 adopts a closed-loop stent with high metal coverage and denser mesh, thereby reducing the risk of plaque escaping from the stent mesh in the internal carotid artery occlusion area after the stent is released.

[0062] (3) The interventional device provided by the present invention includes a push guide wire 300 matched with a double-layer stent. The push guide wire 300 has a double delivery structure. Under the development of clinical surgical medical equipment, the outer stent 100 is released first, and then the inner stent 200 is released at the high-position plaque according to the position of the high-risk plaque. In this way, the high-risk plaque area is protected and the risk of high-risk plaque rupture is reduced.

[0063] (4) It provides better support for the growth of vascular endothelium in the chronic occlusion area of ​​the internal carotid artery, facilitates the repair of vascular endothelium, and reduces the patient's recovery time.

[0064] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. An interventional device for chronic occlusion of the internal carotid artery, characterized in that: It comprises an outer layer stent, an inner layer stent and a pushing guide wire, wherein the outer layer stent and the inner layer stent both have a compression state and an expansion state; When in the pressed and gripped state, the outer layer stent and the inner layer stent are circumferentially arranged around the pushing guide wire and pressed and gripped in the sheath, and the outer layer stent is located at the distal end of the inner layer stent; The distal end of the inner stent is connected to the proximal end of the outer stent via a plurality of silk threads; The distal end of the pushing guide wire is provided with a first pushing portion and a second pushing portion, wherein the first pushing portion is used to push the outer layer stent out of the sheath tube, and the second pushing portion is used to push the inner layer stent out of the sheath tube.

2. The interventional device for chronic occlusion of the internal carotid artery according to claim 1, characterized in that: A first spring is disposed around the outer side of the first pushing portion, and the first spring is used to push the outer layer support; a second spring is disposed around the outer side of the second pushing portion, and the second spring is used to push the inner layer support.

3. The interventional device for chronic occlusion of the internal carotid artery according to claim 2, characterized in that: The first pushing portion and the second pushing portion are both conical, and the diameters of the first pushing portion and the second pushing portion are gradually reduced toward the distal end.

4. The interventional device for chronic occlusion of the internal carotid artery according to claim 1, characterized in that: When in the pressed and gripped state, the outer layer support and the inner layer support are separated by the first pushing portion.

5. The interventional device for chronic occlusion of the internal carotid artery according to claim 1, characterized in that: A buckle is provided at the distal end of the first pushing portion and / or the second pushing portion, and the buckle is used to prevent the outer layer support and / or the inner layer support from moving toward the distal end.

6. The interventional device for chronic occlusion of the internal carotid artery according to claim 1, characterized in that: A first developing portion is disposed at the distal end of the first pushing portion. When in a pressed and gripped state, the first developing portion is located inside the outer layer support.

7. The interventional device for chronic occlusion of the internal carotid artery according to claim 1, characterized in that: A second developing portion is provided between the first pushing portion and the second pushing portion. When in the pressing and gripping state, the second developing portion is located inside the inner layer support.

8. An interventional device for chronic occlusion of the internal carotid artery according to any one of claims 1 to 7, characterized in that: The surfaces of the outer layer stent and the inner layer stent are both provided with anti-stenosis coatings.

9. An interventional device for chronic occlusion of the internal carotid artery according to any one of claims 1 to 7, characterized in that: The outer layer support is an open-loop support.

10. The interventional device for chronic occlusion of the internal carotid artery according to claim 9, characterized in that: The inner layer support is a closed-loop support, and the mesh density of the inner layer support is greater than the mesh density of the outer layer support.

Images