Intravascular stent structural member and intravascular stent

Abstract

The utility model provides an intravascular stent structural member, which relates to the technical field of medical instruments and comprises a plurality of wave-shaped support rings and a plurality of connecting pieces, the wave-shaped support rings and the connecting pieces are arranged at intervals, and the connecting pieces are asymmetrically arranged at two ends of the wave-shaped support rings. The S-shaped connecting pieces with the opposite opening directions are arranged on the two sides of the wave-shaped supporting rings, so that circumferential stretching of the connecting pieces is counteracted, when the wave-shaped supporting rings expand, the adjacent wave-shaped supporting rings reversely rotate in the circumferential direction, and the situation that the intravascular stent structural piece rotates around the axis and drives a micro catheter is prevented; the problem that in the stent releasing process, the stent drives the micro-catheter to rotate, and consequently instability is caused is solved. The utility model further provides an intravascular stent comprising the intravascular stent structural member, and the intravascular stent has good flexibility and trafficability.

Description

Technical Field

[0001] The utility model belongs to the technical field of medical devices, and particularly relates to a vascular stent structural member and a vascular stent. Background Art

[0002] With the development of vascular interventional medical technology, minimally invasive interventional surgery has been widely used in the treatment of stroke, mainly including two types of intracranial vascular diseases: the first is the treatment of intracranial aneurysms. As shown in, the coil embolization technique is often used, that is, a microcatheter is used to deliver coils into the aneurysm cavity to block the blood circulation in the aneurysm and form thrombus to occlude the aneurysm. To prevent the coils from bulging out of the aneurysm cavity and causing vascular stenosis, doctors usually implant auxiliary stents to support the coils at the same time. The second is the vascular stenosis caused by atherosclerosis. Doctors usually implant stents to dilate the stenotic blood vessels to restore them to the required diameter, thereby repairing blood supply. Figure 1 As shown in, the coil embolization technique is often used, that is, a microcatheter is used to deliver coils into the aneurysm cavity to block the blood circulation in the aneurysm and form thrombus to occlude the aneurysm. To prevent the coils from bulging out of the aneurysm cavity and causing vascular stenosis, doctors usually implant auxiliary stents to support the coils at the same time. The second is the vascular stenosis caused by atherosclerosis. Doctors usually implant stents to dilate the stenotic blood vessels to restore them to the required diameter, thereby repairing blood supply.

[0003] The intracranial vascular stent is one of the main instruments for the treatment of intracranial vascular diseases, and its structure is usually connected by several waveform support rings. The commonly used connecting rod shapes at present are straight and curved. The straight connecting rod has a direct force transmission path. The stent using this kind of connecting rod has strong rigidity but insufficient flexibility and is easy to bend when subjected to a large force. The curved connecting rods include U-shaped, S-shaped, etc. Among them, the S-shaped connecting piece has good buffering ability in both the axial and circumferential directions and can significantly improve the flexibility of the stent.

[0004] However, the connection points of the S-shaped connecting piece are usually not parallel to the axis of the waveform support ring. As shown in, when the intracranial vascular stent is released from the microcatheter and starts to expand from the compressed state, the S-shaped connecting piece will also deform due to the change in force at this time, causing the circumferential distance at both ends of the S-shaped connecting piece to change, and further causing the wave peaks and wave valleys of adjacent waveform support rings to form a small-angle rotational misalignment. The displacement amounts of multiple waveform support rings are superimposed on each other, which will cause the stent to continuously rotate around its axis during the process of being released from the microcatheter to being completely released. When clinically releasing the stent, the distal end of the stent first contacts the blood vessel wall and is fixed to the blood vessel wall, while the proximal end is still in the microcatheter, which will drive the microcatheter to rotate and induce the microcatheter to become unstable in the blood vessel. Figure 1 、 2 As shown in, when the intracranial vascular stent is released from the microcatheter and starts to expand from the compressed state, the S-shaped connecting piece will also deform due to the change in force at this time, causing the circumferential distance at both ends of the S-shaped connecting piece to change, and further causing the wave peaks and wave valleys of adjacent waveform support rings to form a small-angle rotational misalignment. The displacement amounts of multiple waveform support rings are superimposed on each other, which will cause the stent to continuously rotate around its axis during the process of being released from the microcatheter to being completely released. When clinically releasing the stent, the distal end of the stent first contacts the blood vessel wall and is fixed to the blood vessel wall, while the proximal end is still in the microcatheter, which will drive the microcatheter to rotate and induce the microcatheter to become unstable in the blood vessel.

[0005] Therefore, it is necessary to provide an improved technical solution to address the deficiencies of the above-mentioned prior art. Summary of the Invention

[0006] The purpose of the utility model is to provide a vascular stent structural member that can overcome rotation around the axis when released from a microcatheter, so as to solve the problem that the stent will drive the microcatheter to rotate and become unstable during the process of releasing the stent from the microcatheter.

[0007] Another object of the present utility model is to provide a vascular stent having the above-mentioned vascular stent structural member.

[0008] To achieve the above object, the present utility model provides the following technical solutions:

[0009] A vascular stent structural member includes a plurality of corrugated support rings and a plurality of connecting members. The corrugated support rings and the connecting members are arranged at intervals, and the connecting members are asymmetrically arranged at both ends of the corrugated support rings.

[0010] Preferably, the connecting member is an S-shaped connecting member.

[0011] Preferably, the opening directions of the S-shaped connecting members on both sides of the corrugated support ring are opposite.

[0012] Preferably, the connecting line between the two ends of the S-shaped connecting member is not parallel to the axis of the corrugated support ring.

[0013] Preferably, the two ends of the S-shaped connecting member are respectively connected to the peak and valley of adjacent corrugated support rings.

[0014] Preferably, the circumferential rotation misalignment angle between the peak and valley connected by the S-shaped connecting member is less than 1 / 2 of the central angle corresponding to the wavelength of the corrugated support ring.

[0015] The present invention also provides a vascular stent, including any of the above-mentioned vascular stent structural members.

[0016] Preferably, it further includes ends, which are arranged on both sides of the vascular stent structural member and connected to the vascular stent structural member.

[0017] Preferably, the ends are connected to the vascular stent structural member by linear connecting members.

[0018] Advantageous effects:

[0019] (1) In the present utility model, S-shaped connecting members with opposite opening directions are arranged on both sides of the corrugated support ring, thereby offsetting the circumferential expansion and contraction of the connecting members. When the corrugated support ring expands, adjacent corrugated support rings rotate in the opposite direction circumferentially, preventing the vascular stent structural member from rotating around the axis and driving the microcatheter, and enabling the entire vascular stent to be pushed out of the microcatheter in a straight line form;

[0020] (2) The S-shaped connecting member used has better elasticity than the linear connecting member, and can compensate for the inner and outer diameter differences caused by bending, enabling the vascular stent to have good elasticity and flexibility for easy delivery, with better passability, easily passing through tortuous intracranial blood vessels, and being able to well adapt to the curvature of blood vessels after stent implantation. Description of the Drawings

[0021] The accompanying drawings of the specification, which form a part of this application, are used to provide a further understanding of the present utility model. The schematic embodiments of the present utility model and their descriptions are used to explain the present utility model and do not constitute an improper limitation to the present utility model. Among them:

[0022] Figure 1 It is a schematic diagram of an existing vascular stent using an S-shaped connector.

[0023] Figure 2 It is a deformation schematic diagram of the S-shaped connector during expansion.

[0024] Figure 3 It is a schematic diagram of the structural member of the vascular stent provided in Embodiment 1 of the present utility model.

[0025] Figure 4 It is a schematic diagram of the structural member of the vascular stent provided in Embodiment 2 of the present utility model.

[0026] Figure 5 It is a schematic diagram of the vascular stent provided in Embodiment 4 of the present utility model.

[0027] In the figure: 100, corrugated support ring; 200, S-shaped connector; 300, end; 400, straight connector. Detailed implementation manners

[0028] Next, the technical solutions in the embodiments of the present utility model will be described clearly and completely. Obviously, the described embodiments are only a part of the embodiments of the present utility model, rather than all the embodiments. Based on the embodiments in the present utility model, all other embodiments obtained by those of ordinary skill in the art belong to the scope protected by the present utility model.

[0029] Term description:

[0030] In the description of the present utility model, "crest" and "trough" refer to the bent parts of the metal wire or non-metal wire that constitutes the corrugated support ring, which are located at both ends of the corrugated support ring along its axis direction. On the same corrugated support ring, if the bend at one end is defined as "crest", then the bent parts at the other end opposite to the "crest" are all "troughs". In the description of the present invention, unless otherwise specified, "crest" refers to the bent part at the left end of the corrugated support ring in the accompanying drawings of the specification, and "trough" refers to the bent part at the right end of the corrugated support ring in the accompanying drawings of the specification.

[0031] In the description of the present invention, "circumferential direction" refers to the direction around the axis of the corrugated support ring.

[0032] In the description of the present utility model, it should be understood that when it comes to orientation descriptions, such as the orientations or positional relationships indicated by up, down, front, back, left, right, etc., they are based on the orientations or positional relationships shown in the drawings. This is only for the convenience of describing the present utility model and simplifying the description, rather than indicating or implying that the device or component referred to must have a specific orientation, be constructed and operated in a specific orientation. Therefore, it should not be construed as a limitation to the present utility model.

[0033] In the description of the present utility model, the meaning of "a number of" is one or more, the meaning of "a plurality of" is more than two, and understandings such as greater than, less than, exceeding, etc. do not include the recited number, while understandings such as above, below, within, etc. include the recited number. If there is a description of first and second, it is only for the purpose of distinguishing technical features and cannot be understood as indicating or implying relative importance or implicitly indicating the quantity of the indicated technical features or implicitly indicating the sequence relationship of the indicated technical features.

[0034] In addition, the terms "first" and "second" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly indicating the quantity of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include one or more features.

[0035] In the description of the present utility model, it should be noted that unless otherwise clearly specified and limited, the term "connection" should be understood in a broad sense. For example, it can be a fixed connection or a movable connection, and can also be a detachable connection or a non-detachable connection, or an integral connection; it can be a mechanical connection, an electrical connection or can communicate with each other; it can be directly connected, or indirectly connected through an intermediate medium, and can be the communication inside two components, indirect communication or the interaction relationship between two components.

[0036] The present utility model will be described in detail below in conjunction with embodiments. It should be noted that, without conflict, the embodiments in the present utility model and the features in the embodiments can be combined with each other.

[0037] Aiming at the problem that the stent rotates around the axis when using a U-shaped or S-shaped curved connector in the current vascular stent, the present utility model provides a structural member of a vascular stent. The structural member includes a number of waveform support rings 100 and a number of connectors. The waveform support rings 100 and the connectors are arranged at intervals, so that adjacent waveform support rings 100 are connected by the connectors, and the connectors are asymmetrically arranged at both ends of the waveform support ring 100.

[0038] In a preferred embodiment of the present utility model, the connector is an S-shaped connector 200, and the opening directions of the S-shaped connectors 200 on both sides of the waveform support ring 100 are opposite, and the connecting line of the two ends of the S-shaped connector 200 is not parallel to the axis of the waveform support ring 100.

[0039] With the above settings, when the vascular stent is released from the microcatheter, as Figure 3 , Figure 4 shown, the acting force directions applied by the same group of S-shaped connectors 200 to the waveform support rings 100 on both sides thereof are opposite, so that the adjacent waveform support rings 100 perform reverse circumferential movements, making the vascular stent structural member as a whole show static around the axis and not twist around the axis, thus solving the problem that the stent will drive the microcatheter to rotate and become unstable during the process of releasing the stent from the microcatheter. In the prior art, as Figure 1 shown, the acting force directions received by the adjacent waveform support rings 100 have no difference, which will cause the vascular stent to show torsion around the axis as a whole.

[0040] The S-shaped connectors 200 are arranged at intervals in the circumferential direction, so that the number of S-shaped connectors 200 is less than the number of wave peaks or wave valleys of the waveform support rings 100 connected thereto, thereby making the compliance of the vascular stent structural member better and easier to pass through the curved blood vessel. For example, one S-shaped connector 200 can be arranged at intervals of 1, 2, 3 or more wave peaks / valleys in the circumferential direction, or two, three or more S-shaped connectors 200 can be arranged at intervals of 1, 2, 3 or more wave peaks / valleys in the circumferential direction.

[0041] In a preferred embodiment of the present invention, the two ends of the S-shaped connector 200 are respectively connected to the wave peak and wave valley of the adjacent waveform support ring 100, which can avoid the S-shaped connector 200 being clamped by the wave peak or wave valley when the vascular stent is in the compressed and gripped state.

[0042] In a preferred embodiment of the present invention, the rotational misalignment angle in the circumferential direction between the wave peak and wave valley connected by the S-shaped connector 200 is less than 1 / 2 of the central angle corresponding to the wavelength of the waveform support ring 100.

[0043] The present invention also provides a vascular stent, including any of the above-mentioned vascular stent structural members. The vascular stent further includes end portions 300, and the end portions 300 are arranged on both sides of the vascular stent structural member and are connected to the vascular stent structural member.

[0044] Specifically, the end portions 300 and the vascular stent structural member are connected by straight connectors 400. The connection method can be either an open loop, so that the number of straight connectors 400 is less than the number of wave valleys of the end portions 300, or a closed loop connection method, so that the number of straight connectors 400 is equal to the number of wave valleys of the end portions 300 to increase its support strength and be more stable when attaching to the wall and not easily generate displacement after attaching to the wall.

[0045] The following further details a vascular stent structural member and a vascular stent of the present invention through specific embodiments.

[0046] Embodiment 1

[0047] As Figure 3 shown, this embodiment provides a vascular stent structural member, which belongs to a partial structural unit of a vascular stent. Specifically, the vascular stent structural member includes two corrugated support rings 100 and S-shaped connectors 200 located at both ends of the corrugated support rings 100. The corrugated support rings 100 and the connectors are arranged at intervals, so that the corrugated support rings 100 are connected by the S-shaped connectors 200. Both ends of the S-shaped connector 200 are respectively connected to the peaks and valleys of adjacent corrugated support rings 100.

[0048] In this embodiment, the opening directions of the S-shaped connectors 200 at both ends of the corrugated support ring 100 are opposite, and the connection line between both ends of the S-shaped connector 200 is not parallel to the axis of the corrugated support ring 100. When the corrugated support ring 100 expands in a zigzag shape from the crimped state, the two ends of the S-shaped connectors 200 at both ends of the corrugated support ring 100 also expand slightly in the circumferential direction, generating a thrust force to push the corrugated support ring 100 to rotate circumferentially around its axis. At the same time, the adjacent corrugated support ring 100 rotates circumferentially in the opposite direction due to the opposite thrust force. The circumferential rotation angles of the two corrugated support rings 100 cancel each other out, so that the vascular stent structural member as a whole shows a state of no circumferential rotation.

[0049] In this embodiment, the circumferential rotation misalignment angle between the peak and valley connected by the S-shaped connector 200 is less than 1 / 2 of the central angle corresponding to the wavelength of the corrugated support ring 100.

[0050] In this embodiment, the number of S-shaped connectors 200 at any one end of the corrugated support ring 100 is less than the number of peaks or valleys of the corrugated support ring 100 on this side, so that the corrugated support rings 100 form an open-loop connection, thereby improving the flexibility of the corrugated support ring 100.

[0051] Embodiment 2

[0052] As Figure 4 shown, this embodiment provides a vascular stent structural member, which belongs to a partial structural unit of a vascular stent. Specifically, the vascular stent structural member includes four corrugated support rings 100 and S-shaped connectors 200 located at both ends of the corrugated support rings 100. The corrugated support rings 100 and the connectors are arranged at intervals, so that the corrugated support rings 100 are connected by the S-shaped connectors 200. Both ends of the S-shaped connector 200 are respectively connected to the peaks and valleys of adjacent corrugated support rings 100.

[0053] In this embodiment, the opening directions of the S-shaped connectors 200 at both ends of the corrugated support ring 100 are opposite, and the connecting line between the two ends of the S-shaped connector 200 is not parallel to the axis of the corrugated support ring 100. When the corrugated support ring 100 expands in a zigzag shape from the compressed state, the two ends of the S-shaped connectors 200 at both ends of the corrugated support ring 100 also expand slightly in the circumferential direction, generating a thrust force to push the corrugated support ring 100 to rotate circumferentially around its axis. At the same time, the adjacent corrugated support ring 100 rotates circumferentially in the opposite direction due to the opposite thrust force, so that the circumferential rotation angles of these two corrugated support rings 100 are offset, thereby making the vascular stent structure as a whole show a state of no circumferential rotation.

[0054] In this embodiment, the circumferential rotation misalignment angle between the wave crest and the wave trough connected by the S-shaped connector 200 is less than 1 / 2 of the central angle corresponding to the wavelength of the corrugated support ring 100.

[0055] In this embodiment, the number of S-shaped connectors 200 at any one end of the corrugated support ring 100 is less than the number of wave crests or wave troughs of the corrugated support ring 100 on this side, so that an open-loop connection is formed between the corrugated support rings 100, thereby improving the flexibility of the corrugated support ring 100.

[0056] Embodiment 3

[0057] This embodiment provides a vascular stent, which includes the vascular stent structure provided in Embodiment 1, and further includes an end portion 300. The end portion 300 is disposed on both sides of the vascular stent structure and is connected to the vascular stent structure.

[0058] In this embodiment, the end portion 300 is connected to the vascular stent structure by a straight connector 400, and each wave crest or wave trough of the end portion 300 is connected to a straight connector 400, thereby forming a closed-loop connection, so that the end portion 300 has relatively higher support strength, is not easily deformed when the vascular stent is pushed in the catheter, and can form an effective support with the blood vessel wall after being released.

[0059] Embodiment 4

[0060] This embodiment provides a vascular stent, as Figure 5 shown, which includes a plurality of vascular stent structures provided in Embodiment 1 or Embodiment 2, and further includes an end portion 300. The end portion 300 is disposed on both sides of the vascular stent structure and is connected to the vascular stent structure.

[0061] In this embodiment, the end portion 300 is connected to the vascular stent structure by a straight connector 400, and each wave crest or wave trough of the end portion 300 is connected to a straight connector 400, thereby forming a closed-loop connection, so that the end portion 300 has relatively higher support strength, is not easily deformed when the vascular stent is pushed in the microcatheter, and can form an effective support with the blood vessel wall after being released.

[0062] In summary:

[0063] In the present utility model, S-shaped connectors 200 with opposite opening directions are arranged on both sides of the corrugated support ring 100, so as to offset the circumferential expansion of the connectors. When the corrugated support ring 100 expands, adjacent corrugated support rings 100 rotate in the opposite direction circumferentially, preventing the structural members of the vascular stent from rotating around the axis and driving the microcatheter, and enabling the entire vascular stent to be pushed out of the microcatheter in a straight line form, thereby solving the problem that when a vascular stent uses a curved connector, it is easy to rotate around the axis during the release process and drive the microcatheter to twist.

[0064] The above are only the preferred embodiments of the present utility model and are not intended to limit the present utility model. For those skilled in the art, the present utility model can have various changes and modifications. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present utility model shall be included within the protection scope of the present utility model.

Claims

1. A vascular stent structure, comprising a plurality of corrugated support rings and a plurality of connecting members, wherein the corrugated support rings and the connecting members are arranged at intervals, characterized in that: When the corrugated support ring expands by itself, the adjacent corrugated support rings rotate in opposite directions in the circumferential direction.

2. A vascular stent structure according to claim 1, characterized in that: The connecting piece is an S-shaped connecting piece.

3. A vascular stent structure according to claim 2, characterized in that: The opening directions of the S-shaped connecting pieces on both sides of the corrugated support ring are opposite.

4. A vascular stent structure according to claim 2 or 3, characterized in that: The connecting line between the two ends of the S-shaped connecting piece is not parallel to the axis of the corrugated support ring.

5. A vascular stent structure according to claim 2 or 3, characterized in that: The two ends of the S-shaped connecting piece are respectively connected to the wave crests and wave troughs of adjacent wave-shaped supporting rings.

6. A vascular stent structure according to claim 5, characterized in that: The rotational misalignment angle of the wave crest and the wave trough connected by the S-shaped connecting piece in the circumferential direction is less than 1 / 2 of the central angle corresponding to the wavelength of the wave support ring.

7. A vascular stent, characterized in that: It comprises the vascular stent structure as claimed in any one of claims 1 to 6.

8. A vascular stent according to claim 7, characterized in that: It also includes end portions, which are arranged on both sides of the blood vessel support structure and connected to the blood vessel support structure.

9. The vascular stent according to claim 8, characterized in that: The end portion is connected to the blood vessel support structure through a straight-line connector.

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