Open-loop and closed-loop segment hybrid vascular stent and stent assembly

Abstract

The present invention relates to an open-loop and closed-loop segment hybrid vascular stent and a stent assembly. The vascular stent comprises an open-loop stent segment and a closed-loop stent segment connected in sequence from right to left. The open-loop stent segment is defined as having a plurality of support rib groups arranged from right to left, each support rib group having a row of transversely arranged support ribs or at least two rows of support ribs arranged from right to left, the number of support ribs in each row in the same group being the same, and the number of support ribs in each row in the support rib group on the right side of two adjacent support rib groups being less than the number of support ribs in each row in the support rib group on the left side, so that the open-loop stent segment is gradually closed from right to left; the left end of the closed-loop stent segment constitutes a probing end for extending from a catheter, the protruding points of the open loop are gradually narrowed, the protruding points gradually increase, the supporting force of the open-loop stent segment from left to right gradually increases, and the supporting stability of the overall stent is further ensured, and the closed-loop stent can facilitate the overall vascular stent to be retracted into the catheter.

Description

Technical Field

[0001] The invention relates to an open-loop and closed-loop segment hybrid blood vessel stent and a stent assembly. Background Art

[0002] Intracranial arterial atherosclerosis and stenosis are important causes of ischemic stroke. With the advancement of device technology and the increase in the experience of neurointerventionalists, intracranial arteriovenous angioplasty plus stent implantation is the main treatment method, which has the characteristics of less trauma, high predictability, rapid patient recovery, and high surgical safety. The stents used for such diseases are mainly made of 316 medical stainless steel, cobalt-chromium alloy, titanium alloy and other biomedical metals with good biological functionality and excellent processing performance. These metals have good cell compatibility and mechanical properties similar to those of blood vessels. The stent is placed in the blood vessel, and it must have a tubular structure corresponding to the blood vessel. In addition, for the consideration of thrombus inhibition, drug spraying, radial and axial performance of the stent, the stent is generally designed as a mesh structure to reduce the metal coverage of the blood vessel and ensure good radial support and expansion uniformity.

[0003] However, the intracranial arteries have their own special structural morphology: first, the intracranial arteries are tortuous, especially the blood vessels with severe atherosclerosis; second, the walls of the intracranial arteries are thin and lack elasticity; third, they are located in the cerebrospinal fluid of the subarachnoid space, with no tissue surrounding and support.

[0004] Common vascular stents currently on the market generally include multiple rows of support rings arranged in the longitudinal direction, and the support rings have several mesh edges, each of which is connected end to end in the transverse direction, and each mesh edge is a straight edge or a sine wave edge or an arc edge. And the two adjacent mesh edges are arranged at a certain angle, so that the support rings have several connection points protruding in the axial direction in opposite directions, and the two adjacent support rings are connected by support ribs to form the final vascular stent. According to the connection form of the support ribs, the existing vascular stents can be divided into two forms: one, a closed-loop stent, that is, a stent formed by connecting a closed-loop grid structure, in two adjacent rows of support rings, each of the two longitudinally opposite connection points is connected by support ribs, and the support ribs and the mesh edges are surrounded to form a closed grid; two, an open-loop stent, in two adjacent rows of support rings, some of the longitudinally opposite connection points are connected by support ribs, and the unconnected connection points are arranged alternately with the support ribs in sequence, and the corresponding connection points between the two adjacent support ribs protrude in the longitudinal direction to form a protruding point.

[0005] In actual use, the closed-loop stent forms a closed loop in each part of the blood vessel. At positions with different blood vessel diameters, some segments of the stent have a greater supporting force on the blood vessel wall, while other segments of the stent have a smaller supporting force on the blood vessel wall. Even at the corner of the blood vessel, the closed-loop stent is closed as a whole, resulting in an angle between the end and the whole, which causes the end of the closed-loop stent to be suspended in the air and unable to contact the blood vessel wall, thereby losing effective support for the blood vessel wall. However, since the open-loop stent has multiple laterally arranged connection points, when the open-loop stent is extended from the catheter to test the rationality of the stent placement position, the open-loop stent expands outward due to its own elasticity, and the protruding points on the part of the stent extending out of the catheter protrude outward, thereby adhering to the blood vessel wall. When this open-loop stent is used clinically, when the angiography end of the stent is extended out of the catheter, if the placement position of the stent is unreasonable and the positioning position of the plaque in the blood vessel is inaccurate, the protruding points are stuck at the end of the catheter, making it impossible for the stent to be retracted into the catheter. Summary of the invention

[0006] The purpose of the present invention is to provide a hybrid vascular stent of open-loop and closed-loop segments to solve the problems in the prior art of insufficient supporting force of closed-loop stents and inability of open-loop stents to be retracted into the catheter; the purpose of the present invention is also to provide a stent assembly using the vascular stent.

[0007] In order to solve the above problems, the open-loop and closed-loop segment hybrid vascular stent involved in the present invention adopts the following technical solutions:

[0008] An open-loop and closed-loop segment hybrid vascular stent comprises an open-loop stent segment and a closed-loop stent segment connected in sequence from right to left. The open-loop stent segment is defined as having multiple groups of support ribs arranged from right to left, each support rib group having a row of transversely arranged support ribs or at least two rows of support ribs arranged from right to left, the number of support ribs in each row in the same group being the same, and the number of support ribs in each row in the support rib group on the right side of two adjacent support rib groups being less than the number of support ribs in each row in the support rib group on the left side, so that the open-loop stent segment gradually closes from right to left; the left end of the closed-loop stent segment constitutes a probing end for extending out of a catheter.

[0009] Furthermore, each row of support ribs of the closed-loop support segment and adjacent mesh edges form a grid, and the closed-loop support segment is defined as having multiple grid groups, each grid group having a row of grids or at least two rows of grids arranged in sequence left and right, the number of grids in each row in the same grid group is the same, and in two adjacent grid groups, the number of grids in the grid group on the right is greater than the number of grids in the grid group on the left, so that the grid of the closed-loop support segment gradually becomes sparse from right to left.

[0010] Furthermore, the grid group located in the middle of each grid group of the closed-loop stent segment constitutes a support segment for supporting the plaque in the blood vessel, and the length of the support segment is 1 / 3 to 1 / 2 of the overall length of the vascular stent.

[0011] Furthermore, developing parts are arranged at both ends of the blood vessel stent and at each protruding point of the open-loop stent segment.

[0012] Furthermore, each protruding point at the left and right ends of the vascular stent smoothly transitions with two adjacent mesh edges to form a curved support structure.

[0013] The bracket assembly involved in the present invention adopts the following technical solutions:

[0014] The stent assembly includes a catheter and a guide wire installed in the catheter, and a vascular stent is wrapped on the outside of the guide wire. The left end of the catheter is defined as an insertion end for inserting into the blood vessel, and the vascular stent includes an open-loop stent segment and a closed-loop stent segment connected in sequence from right to left. The open-loop stent segment is defined as having multiple groups of support rib groups arranged from right to left, each support rib group has a row of transversely arranged support ribs or at least two rows of support ribs arranged from right to left, and the number of support ribs in each row in the same group is the same. In two adjacent groups of support rib groups, the number of support ribs in each row in the support rib group located on the right is less than the number of support ribs in each row in the support rib group located on the left, so that the open-loop stent segment forms a gradually closed structure; the left end of the closed-loop stent segment is close to the insertion end of the catheter and constitutes a tentative end.

[0015] Furthermore, each row of support ribs of the closed-loop support segment and adjacent mesh edges form a grid, and the closed-loop support segment is defined as having multiple grid groups, each grid group having a row of grids or at least two rows of grids arranged in sequence left and right, the number of grids in each row in the same grid group is the same, and in two adjacent grid groups, the number of grids in the grid group on the right is greater than the number of grids in the grid group on the left, so that the grid of the closed-loop support segment gradually becomes sparse from right to left.

[0016] Furthermore, the rightmost grid group among the grid groups of the closed-loop stent segment constitutes a support segment for supporting a plaque in a blood vessel.

[0017] Furthermore, developing parts are arranged at both ends of the blood vessel stent and at each protruding point of the open-loop stent segment.

[0018] Furthermore, each protruding point at the left and right ends of the vascular stent smoothly transitions with two adjacent mesh edges to form a curved support structure.

[0019] The beneficial effects of the present invention are as follows: Compared with the prior art, the hybrid open-loop and closed-loop segment vascular stent involved in the present invention, by setting the vascular stent as an open-loop and closed-loop hybrid structure, in actual use, the closed-loop stent segment mainly plays the role of extending from the catheter after entering the blood vessel to test and support the blood vessel wall, and at the same time, each axial part of the closed-loop stent segment has a certain radial expansion support force, which can provide a relatively stable support for the support area in the blood vessel. In the actual stent placement process, the tapered structure of the open-loop stent can have enough protruding points abutting against the inner wall of the blood vessel extending at different positions and angles to ensure a certain support stability; the protruding points of the open loop are gradually narrowed, so that the number of protruding points gradually increases, and the support force of the open-loop stent segment from left to right gradually increases, further ensuring the support stability of the overall stent. When the vascular stent is extended from the catheter and follows the guide wire into the blood vessel, the vascular stent has its own elasticity and expands outward. At this time, the closed-loop stent segment is first extended into the blood vessel. When it is determined that the plaque position is inconsistent with the actual position, the guide wire can be retracted. The setting of the closed-loop stent can also facilitate the retraction of the entire vascular stent into the catheter. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In order to more clearly illustrate the technical solution of the embodiment of the present invention, the following briefly introduces the drawings required for use in the embodiment:

[0021] Figure 1 It is a schematic structural diagram of a specific embodiment of the open-loop and closed-loop hybrid vascular stent of the present invention;

[0022] Figure 2 for Figure 1 A local enlarged view of point A;

[0023] Figure 3 for Figure 1 The layout diagram of the vascular stent in the blood vessel;

[0024] Figure 4 It is a schematic structural diagram of an embodiment of a bracket assembly involved in the present invention.

[0025] Explanation of the reference numerals: 1 - open-loop stent segment; 2 - closed-loop stent segment; 3 - support segment; 4 - protruding point; 5 - developing part; 6 - grid; 7 - support rib; 8 - grid edge; 9 - guide wire; 10 - catheter. DETAILED DESCRIPTION

[0026] In order to make the technical purpose, technical solution and beneficial effects of the present invention more clear, the technical solution of the present invention is further described below in conjunction with the accompanying drawings and specific embodiments.

[0027] The specific embodiments of the open-loop and closed-loop hybrid vascular stent involved in the present invention are as follows: Figure 1 , Figure 2 and Figure 3 As shown, the main structure of the vascular stent is basically consistent with the prior art, including multiple rows of support rings arranged in the longitudinal direction, the support rings have a plurality of mesh edges 8, each mesh edge 8 is sequentially connected end to end in the transverse direction, and each mesh edge 8 is a straight edge or a sine wave edge or an arc edge. Two adjacent mesh edges 8 are arranged at a certain angle, so that the support rings have a plurality of connection points protruding in the axial direction in opposite directions, and the two adjacent support rings are connected to the above connection points through support ribs 7 to form the final vascular stent.

[0028] The vascular stent in this embodiment includes an open-loop stent segment 1 and a closed-loop stent segment 2 connected in sequence from right to left. The open-loop stent segment 1 is defined as having multiple groups of support ribs arranged from right to left, each of which has one row of support ribs 7 or more than two rows of support ribs 7 arranged from right to left, the number of support ribs 7 in each row in the same group is the same, and in two adjacent groups of support ribs, the number of support ribs 7 in each row in the support rib group on the right is less than the number of support ribs 7 in each row in the support rib group on the left, so that the open-loop stent segment 1 is gradually closed from right to left; the left end of the closed-loop stent segment 2 constitutes a probing end for extending from the catheter 10.

[0029] As for the closed-loop support segment 2, each row of support ribs 7 of the closed-loop support segment 2 and the adjacent mesh edges 8 together form a grid 6, and the closed-loop support segment 2 is defined as having multiple grid groups, each grid group having a row of grids 6 or at least two rows of grids 6 arranged in sequence left and right, and the number of grids 6 in each row in the same grid group is the same. In two adjacent grid groups, the number of grids 6 in the grid group on the right is greater than the number of grids 6 in the grid group on the left, so that the grids 6 of the closed-loop support segment 2 are gradually sparse from right to left.

[0030] That is to say, the overall structure of the open-loop stent segment 1 gradually shrinks from right to left; the structure of the closed-loop stent segment 2 is free to gradually sparse the mesh opening to the left, thereby forming a gradual stent structure between the overall blood vessels. With this arrangement, for the open-loop stent segment 1, the gradually shrinking structure of the open-loop stent can have enough protrusions 4 against the inner wall of the blood vessel extending at different positions and angles, ensuring a certain support stability; the open-loop protrusions 4 are gradually shrinking, so that the number of protrusions 4 gradually increases, and the support force of the open-loop stent segment 1 from left to right gradually increases, further ensuring the support stability of the overall stent. For the closed-loop stent segment 2, the structure of the closed-loop stent segment 2 with gradually sparse mesh openings can avoid excessive opening of the blood vessel wall due to the large expansion support force on the normal blood vessel wall during actual use, and can also avoid interference with the braided blood vessels, branch blood vessels, and especially the areas with dense perforators.

[0031] At the same time, the rightmost grid group of each grid group of the closed-loop stent segment 2 constitutes a support segment 3 for supporting the plaque in the blood vessel. In this embodiment, the rightmost grid group of the closed-loop stent segment 2 includes several rows of grids 6, and the number of each row of grids 6 is the same, so as to ensure that the radial support force at each position of the support group during radial expansion in the blood vessel is consistent, thereby achieving stable support for the plaque. The length of the grid group is 2 / 5 of the length of the entire vascular stent. In addition to ensuring effective support for the plaque, this arrangement can also ensure effective support for the blood vessel wall by the open-loop stent segment 1 as a whole and the sparse and gradually changing mesh part of the closed-loop stent segment 2.

[0032] At the same time, in order to determine the position of each part of the intravascular stent placement position, different from the existing method of arranging the development structure only at the two ends of the stent, the two ends of the vascular stent and the protruding points 4 of the open-loop stent segment 1 in this embodiment are provided with development parts 5. In this way, after the vascular stent is extended into the blood vessel, the position of each part of each vascular stent can be accurately located through the development part 5, thereby ensuring the accuracy of the support position of the stent for the plaque.

[0033] At the same time, in order to prevent the end of the vascular stent from puncturing or scratching the corner of the vascular wall or the vascular wall of the branch blood vessel during the extension process when the vascular stent is extended into the blood vessel, each protruding point 4 at the left and right ends of the vascular stent smoothly transitions with the two adjacent mesh edges 8 to form a curved support structure. This arrangement has no sharp protrusions, ensuring smooth extension of the vascular stent.

[0034] Of course, in the actual insertion process, the probing end of the closed-loop stent segment 2, that is, the left end, is inserted into the blood vessel. If the plaque cannot be detected after being far away from the plaque, the open-loop stent segment 1 is still in the catheter 10, and the protruding points 4 are not exposed. At this time, the closed-loop stent segment 2 can be directly received into the catheter 10, and the catheter 10 can continue to move to the plaque position; after reaching the plaque position, the sparse and gradual section of the closed-loop stent segment 2 can effectively pass through the plaque area and avoid affecting the collateral and branch vessels. After the vascular stent is placed in the blood vessel as a whole, the protruding points 4 of the open-loop stent segment 1 on the right side gradually increase, and the adhesion to the blood vessel wall also gradually increases, ensuring the support stability of the stent.

[0035] The embodiment of the bracket assembly involved in the present invention is as follows Figure 4 As shown, it includes a catheter 10 and a guide wire 9 installed in the catheter 10. The guide wire 9 is wrapped with a vascular stent. The structure of the vascular stent is consistent with the structure of the above-mentioned embodiment of the vascular stent, and will not be described in detail.

[0036] Finally, it should be noted that the above embodiments are only used to illustrate but not limit the technical solutions of the present invention, and any equivalent substitutions of the present invention and any modifications or partial substitutions that do not depart from the spirit and scope of the present invention should be included in the scope of protection of the claims of the present invention.

Claims

1. An open-loop and closed-loop segment hybrid vascular stent, characterized in that: The invention comprises an open-loop support segment and a closed-loop support segment connected in sequence from right to left. The open-loop support segment is defined as having a plurality of support rib groups arranged from right to left. Each support rib group has a row of transversely arranged support ribs or at least two rows of support ribs arranged from right to left. The number of support ribs in each row in the same group is the same. In two adjacent groups of support rib groups, the number of support ribs in each row in the support rib group on the right is less than the number of support ribs in each row in the support rib group on the left, so that the open-loop support segment is gradually closed from right to left. The left end of the closed-loop support segment constitutes a probing end for extending from a catheter. The rows of support ribs in the closed-loop support segment and the adjacent mesh edges are combined to form a grid. The closed-loop support segment is defined as The segment has multiple grid groups, each grid group has a row of grids or at least two rows of grids arranged in sequence on the left and right, the number of grids in each row in the same grid group is the same, and in two adjacent grid groups, the number of grids in the grid group located on the right is greater than the number of grids in the grid group located on the left, so that the grids of the closed-loop stent segment are gradually sparse from right to left; the grid group located in the middle position of each grid group of the closed-loop stent segment constitutes a support segment for supporting the plaque in the blood vessel, and the length of the support segment is 1 / 3 to 1 / 2 of the overall length of the vascular stent; each protruding point on the left and right ends of the vascular stent smoothly transitions with the two adjacent mesh edges to form a curved support structure.

2. The open-loop and closed-loop segment hybrid vascular stent according to claim 1, characterized in that: The two ends of the blood vessel stent and the protruding points of the open-loop stent segment are arranged with developing parts.

3. A stent assembly, comprising a catheter and a guide wire inserted into the catheter, wherein the guide wire is wrapped with a vascular stent, wherein the left end of the catheter is defined as an insertion end for inserting into a blood vessel, and wherein: The vascular stent comprises an open-loop stent segment and a closed-loop stent segment connected in sequence from right to left. The open-loop stent segment is defined as having a plurality of support rib groups arranged from right to left, each support rib group having a row of transversely arranged support ribs or at least two rows of support ribs arranged from right to left, the number of support ribs in each row in the same group being the same, and the number of support ribs in each row in the support rib group on the right side of two adjacent support rib groups being less than the number of support ribs in each row in the support rib group on the left side, so that the open-loop stent segment forms a gradually closed structure; the left end of the closed-loop stent segment is close to the insertion end of the catheter to form a probing end; the rows of support ribs in the closed-loop stent segment are connected to the adjacent mesh. The edges are surrounded to form a grid, and the closed-loop stent segment is defined as having multiple grid groups, each grid group has a row of grids or at least two rows of grids arranged in sequence from left to right, the number of grids in each row in the same grid group is the same, and in two adjacent grid groups, the number of grids in the grid group located on the right is greater than the number of grids in the grid group located on the left, so that the grid of the closed-loop stent segment is gradually sparse from right to left; the grid group located on the far right of each grid group of the closed-loop stent segment constitutes a support segment for supporting the plaque in the blood vessel; each protruding point on the left and right ends of the blood vessel stent smoothly transitions with the two adjacent mesh edges to form a curved support structure.

4. The bracket assembly according to claim 3, characterized in that: The two ends of the blood vessel stent and the protruding points of the open-loop stent segment are arranged with developing parts.

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