CN219271248U - Vascular stent - Google Patents

Abstract

The utility model provides a vascular stent, which comprises a stent main body, a flare section and a transition section positioned between the stent main body and the flare section, wherein the vascular stent meets at least one of the following conditions: the wave height of the transition section is smaller than the wave height of the bracket main body and/or the wave height of the horn mouth section; the rod width of the transition section is smaller than the rod width of the bracket main body and/or the rod width of the bell mouth section; the number of heads of the transition section is not less than that of the stent main body and/or that of the horn mouth section, so that the adherence performance of the transition section is improved, and the probability of occurrence of long-term thrombosis and restenosis in the stent is reduced.

Description

Vascular stent

Technical Field

The utility model relates to the technical field of medical appliances, in particular to a vascular stent with good adherence.

Background

The close end or far end of the vascular stent has a difference with the central part of the vascular stent in the adherence condition of the proximal end or the far end of the vascular stent, and the proximal end or the far end of the common vascular stent is cylindrical barrel-shaped (the diameters of the two ends of the stent are consistent with the diameter of the stent main body) or flared (the diameters of the two ends of the stent are larger than the diameter of the stent main body). After the vascular stent is implanted, the proximal end or the distal end wave rod of the cylindrical barrel-shaped stent has a tendency of converging inwards towards the central axis of the stent, namely, compared with the stent main body, the proximal end or the distal end of the vascular stent has poor adhesion, and thrombus risks exist in a long term. Therefore, the flaring (flaring) is arranged at the proximal end or the distal end of the vascular stent, so that the effect of enhancing the adhesion of the proximal end or the distal end of the vascular stent is achieved, and the flaring can also play a role of increasing the anchoring property in the release process of the vascular stent.

Common vascular stents with a flare, the flare section is consistent with the stent body wave form design. The design can solve the problem of poor adhesion of the end part of the vascular stent to a certain extent, but is unfavorable for adhesion of the transition section between the flare section and the stent main body. It is actually shown that the adhesion of the transition position between the flare section and the stent body is generally worse than that of the flare body and the stent body, and the poor adhesion of the transition section may be a cause of long-term thrombosis and restenosis in the stent.

Disclosure of Invention

The utility model aims to provide a vascular stent so as to improve the adherence performance of a transition section between a flare section and a stent main body and reduce the risk of long-term thrombosis and restenosis in the stent.

To achieve the above object, the present utility model provides a vascular stent comprising a stent body, a flare section and a transition section between the stent body and the flare section, wherein the vascular stent satisfies at least one of the following conditions:

the wave height of the transition section is smaller than the wave height of the bracket main body and/or the wave height of the horn mouth section;

the rod width of the transition section is smaller than the rod width of the bracket main body and/or the rod width of the bell mouth section;

the number of heads of the transition section is not smaller than that of the bracket main body and/or that of the bell mouth section.

Optionally, the vascular stent is provided with a plurality of stent circumferential rings which are sequentially arranged along the axial direction of the vascular stent, wherein the stent circumferential rings are composed of waverods which are sequentially connected end to end; in the axial direction of the vascular stent, the peaks and the troughs of any two adjacent circumferential rings of the stent are connected through connecting rods, and the number of the connecting rods at the same circumferential position in the transition section is smaller than or equal to the number of heads of the circumferential rings of the stent connected by the connecting rods.

Optionally, the number of connecting rods at the same circumferential position in the transition section is smaller than the number of heads of the stent circumferential rings in the stent body and/or the number of heads of the stent circumferential rings in the flare section.

Optionally, the number of connecting rods at the same circumferential position in the stent body is smaller than or equal to the number of heads of the stent circumferential rings to which the connecting rods are connected, and/or the number of connecting rods at the same circumferential position in the bell mouth section is smaller than or equal to the number of heads of the stent circumferential rings to which the connecting rods are connected.

Optionally, the number of the connecting rods at the same circumferential position is smaller than the number of heads of the circumferential rings of the bracket connected at the two axial sides of the connecting rod.

Optionally, the wave height of the bracket main body is a first wave height, the wave height of the horn mouth section is a third wave height, and the first wave height and the third wave height are equal or unequal.

Optionally, the first wave height and/or the third wave height is 1.2 mm-20 mm.

Optionally, the first wave height and/or the third wave height is 1.2 mm-1.8 mm.

Optionally, the wave height of the transition section is a second wave height, and the second wave height is 0.8 mm-20.0 mm.

Optionally, the second wave height is 1.0 mm-1.6 mm.

Optionally, the width of the stem of the bracket body is a first width of the stem, the width of the stem of the flare section is a third width of the stem, and the first width of the stem and the third width of the stem are equal or unequal.

Optionally, the first bar width and/or the third bar width is 35 μm to 120 μm.

Optionally, the first stem width and/or the third stem width is 40 μm to 60 μm.

Optionally, the transition section has a second bar width of 15 μm to 60 μm.

Optionally, the second bar width is 20 μm to 35 μm.

Optionally, the wave head of the bracket main body is a first head number, the wave head of the bell mouth section is a third head number, and the first head number is equal to or unequal to the third head number.

Optionally, the wave head of the transition section is a second head number, the ratio of the second head number to the first head number is 1.0-2.0, and/or the ratio of the second head number to the third head number is 1.0-2.0.

Optionally, the ratio of the second number of heads to the first number of heads is 1.5, and/or the ratio of the second number of heads to the third number of heads is 1.5.

Optionally, only the proximal end of the stent body is provided with the flare section, or both the proximal and distal ends of the stent body are provided with the flare section.

Optionally, the connecting rod is a straight rod, a curved rod or a broken line rod.

Optionally, the material of the vascular stent is an elastic material, a shape memory alloy material or a degradable material.

Optionally, the flare section includes only a flare body, or the flare section includes a flare body and a flare tip, and a portion of the peak at the end of the flare body distal from the transition section protrudes axially to form the flare tip.

In the vascular stent provided by the utility model, the vascular stent comprises: a stent body, a flare section, and a transition section between the stent body and the flare section, the vascular stent satisfying at least one of the following conditions: the wave height of the transition section is smaller than the wave height of the bracket main body and/or the wave height of the horn mouth section; the rod width of the transition section is smaller than the rod width of the bracket main body and/or the rod width of the bell mouth section; the number of heads of the transition section is not smaller than that of the bracket main body and/or that of the bell mouth section. When the transition section is arranged according to any one or more conditions, the transition section has good adherence effect, and when the vascular stent is released into a blood vessel with the shape of tortuosity, the risk of long-term thrombosis of the vascular stent and the occurrence probability of restenosis in the stent can be reduced under the condition that the adherence effect of the transition section is good. Furthermore, the number of connecting rods at the same circumferential position in the transition section is smaller than the number of heads of circumferential rings of the stent connected with the connecting rods, so that the transition section is in an open-loop structure, the situation that the vascular stent is extremely not adhered to walls, such as 'king', bending kinking and the like, when the vascular stent is released to a bent blood vessel can be reduced, and the adhesion of the transition section is remarkably improved.

Drawings

Those of ordinary skill in the art will appreciate that the figures are provided for a better understanding of the present utility model and do not constitute any limitation on the scope of the present utility model. Wherein:

fig. 1 is a schematic structural view of a vascular stent according to a first embodiment of the present utility model when the vascular stent is cut and spread along the axial direction thereof;

fig. 2 is a partial enlarged view of a stent body when a vascular stent according to the first embodiment of the present utility model is cut and spread along the axial direction thereof, wherein the stent body has an open loop structure;

FIG. 3 is an enlarged view of a portion of a transition section between a flare section and a stent body when the stent of the first embodiment of the present utility model is cut open and spread in the axial direction of the stent itself;

fig. 4 is a partial enlarged view of a stent body when the vascular stent according to the first embodiment of the present utility model is cut and spread along the axial direction thereof, wherein the stent body has a closed loop structure;

fig. 5 is a schematic structural view of a vascular stent according to a second embodiment of the present utility model when the vascular stent is cut and spread along the axial direction thereof;

fig. 6 is a partial enlarged view of a transition section between a flare section and a stent body when the stent of the second embodiment of the present utility model is cut open and spread in the axial direction of the stent itself.

In the accompanying drawings:

1-a stent body; 11-protrusions; 2-transition section; 3-flare section; 31-a flare body; 32-flare tip; 4-a stent circumferential ring; 41-wave beam; 42-bending sections; 5-connecting rods; h 1-a first wave height; h 2-a second wave height; h 3-third wave height; b1-first pole width; b2-second pole width; b3-third bar width.

Detailed Description

The utility model is described in further detail below with reference to the drawings and the specific examples. The advantages and features of the present utility model will become more apparent from the following description. It should be noted that the drawings are in a very simplified form and are all to a non-precise scale, merely for convenience and clarity in aiding in the description of embodiments of the utility model. Furthermore, the structures shown in the drawings are often part of actual structures. In particular, the drawings are shown with different emphasis instead being placed upon illustrating the various embodiments. It should be further understood that the terms "first," "second," "third," and the like in this specification are used merely for distinguishing between various components, elements, steps, etc. in the specification and not for indicating a logical or sequential relationship between the various components, elements, steps, etc., unless otherwise indicated.

In this document, "proximal" and "distal" are relative orientations, relative positions, directions of elements or actions relative to one another from the perspective of a physician using the stent, although "proximal" and "distal" are not limiting, "proximal" generally refers to an end of the stent that is proximal to the physician during normal operation, and "distal" generally refers to an end that first enters the patient.

In this document, "axial" generally refers to a direction corresponding to a central axis of a stent, while "radial" generally refers to a diameter direction corresponding to a stent, and "circumferential" generally refers to a direction about a central axis of a stent; the wave height is the projection length of the wave rod and the bending sections on the two sides of the wave rod in the axial direction of the bracket main body, namely the height between the adjacent wave crests and wave troughs on the circumferential ring of the bracket; "rod width" generally refers to the rod width of a body of the wave rod that does not include a bending section (corresponding to a peak or trough) in the wave rod; if the vascular stent has the design of increasing the rod width such as grooving medicine carrying, developing point crimping and the like, the rod width is still the rod width of the wave rod main body; "number of heads" refers to the number of peaks or the number of valleys on a circumferential ring of a stent; the wave rod is a bracket edge or a bracket rod; "diameter" refers to the outer diameter of a vascular stent.

The utility model aims at providing a vascular stent to solve the problem of poor adhesion of a transition section between a bell mouth section and a stent main body in the existing vascular stent.

The vascular stent provided by the utility model can improve the adherence of the transition section, and further can reduce the occurrence rate of long-term adverse events such as thrombus, restenosis and the like to a certain extent.

The vascular stent provided by the utility model is mainly a cutting stent and comprises a stent main body, a horn mouth section and a transition section positioned between the stent main body and the horn mouth section. Wherein the bracket main body is provided with a flare section at least one end in the axial direction, and the diameter of the flare section is larger than that of the bracket main body. If only one axial end of the support body is provided with a flare section, the proximal axial end of the support body is preferably provided with a flare section. This is based mainly on the following considerations: for the operator (the operator), the release of the vascular stent is highly controllable in the position of the distal end, which is usually released in a relatively straight vascular position; the release position of the proximal end of the vascular stent is often influenced by factors such as stent shrinkage, vascular tortuosity and the like, and the actual release position may be different from the surgical scheme; the flare section is thus disposed at the proximal end of the stent to promote proximal apposition.

The following description refers to the accompanying drawings, and the following embodiments and features of the embodiments may be mutually complementary or combined without conflict.

[ embodiment one ]

Fig. 1 to 4 show an exemplary structure of a stent according to a first embodiment of the present utility model. As shown in fig. 1 to 4, the vascular stent comprises a stent body 1, a flare section 3, and a transition section 2 between the stent body 1 and the flare section 3.

In this embodiment, two ends of the bracket main body 1 in the axial direction are provided with a flare section 3. The diameter of the flare section 3 is larger than the diameter of the stent body 1. Since the diameter of the flare section 3 is different from the diameter of the holder body 1, a smooth transition between the flare section 3 and the holder body 1 is ensured by the arrangement of the transition section 2. It should be noted that, the schematic drawing in the present utility model is a schematic drawing in which the stent is cut and flattened along the axial direction thereof, the three-dimensional structure of the stent is not shown in the schematic drawing, and the flare is usually obtained by heat setting treatment and is usually shown in the three-dimensional drawing, so that the structure in which the diameter of the flare section 3 is larger than the diameter of the stent body 1 is not shown in the schematic drawing in which the stent is cut and flattened along the axial direction thereof.

In some embodiments, the flare section 3 comprises a flare body 31 and a flare tip 32, the flare body 31 being disposed between the flare tip 32 and the transition section 2, the flare body 31 being directly connected to the transition section 2. At this time, a developing structure such as a developing sleeve or a developing spring may be mounted on the flare tip 32. The flare tip 32 is understood to be the part of the peak at the end of the flare body 31 remote from the transition piece 2 that protrudes in the axial direction. In other embodiments, the flare section 3 comprises only the flare body 31 without the flare tip 32, in which case all peaks at the end of the flare body 31 remote from the transition section 2 are not axially protruding, which is also within the scope of the present utility model.

In some embodiments, the wave height of the transition section 2 is smaller than the wave height of the flare body 31 and/or the wave height of the transition section 2 is smaller than the wave height of the stent body 1; so that the transition section 2 can be better attached to the shape of the bent blood vessel, and the attachment property of the transition section 2 is improved.

In some embodiments, the stem width of the transition section 2 is less than the stem width of the flare body 31 and/or the stem width of the transition section 2 is less than the stem width of the bracket body 1; so that the transition section 2 can be better attached to the shape of the bent blood vessel, and the attachment property of the transition section 2 is improved. In the scheme, although the supporting force of the transition section 2 is slightly reduced, the flexibility is better, and the transition section 2 can be better attached to the shape of a blood vessel, so that the attachment property of the transition section 2 is improved.

In some embodiments, the wave height of the transition section 2 is smaller than the wave height of at least one of the bell mouth body 31 and the bracket body 1, while the rod width of the transition section 2 is smaller than the rod width of at least one of the bell mouth body 31 and the bracket body 1, thereby adjusting the wave height and the rod width of the transition section 2 at the same time. So configured, on the basis of ensuring that the supporting force of the transition section 2 is consistent with that of the stent main body 1 or the bell mouth main body 31, the performance of the transition section 2 attached to the vessel wall is improved to the greatest extent.

When at least one of the wave height and the rod width of the transition section 2 is configured as described above, the transition section 2 has a good adherence effect. When the vascular stent is released into the blood vessel with the shape of tortuosity, the risk of long-term thrombosis of the vascular stent and the occurrence probability of restenosis in the vascular stent can be reduced under the condition that the adherence effect of the transition section 2 is good. Therefore, the wave design of the transition piece 2 is different from the wave design of the bracket body 1 and/or the flare body 31, thereby improving the adherence performance of the transition piece 2.

In addition to the above, in another embodiment, the number of heads of the transition section 2 is not less than that of the stent body 1, and/or the number of heads of the transition section 2 is not less than that of the flare section 3, so that the adhesion of the vascular stent is better, especially the adhesion in the circumferential direction is better. In other words, the number of heads of the stent circumferential ring 4 in the transition section 2 is not less than the number of heads of the stent circumferential ring 4 in the stent body 1, and/or the number of heads of the stent circumferential ring 4 in the transition section 2 is not less than the number of heads of the stent circumferential ring 4 in the flare section 3.

Optionally, the number of heads of the transition section 2 is 16 more than the number of heads of the bracket body 1 and/or the bell mouth body 31, preferably no more than 16 more. Further, the number of heads of the bell mouth body 31 is equal to that of the bracket body 1, or the number of heads of the bell mouth body 31 is equal to that of the transition section 2.

The vascular stent is typically a cutting stent having a plurality of circumferential rings 4 of the stent (i.e. annular stent segments) arranged in sequence along its own axis. The shape of the waveform of the stent circumferential ring 4 is not limited and is generally a zigzag or sinusoidal waveform. The bracket circumferential ring 4 is composed of a plurality of wave rods 41 which are connected end to end in sequence. In the axial direction of the vascular stent, the peaks and the troughs of any two adjacent stent circumferential rings 4 are connected through a connecting rod 5. The support circumferential ring 4 is unfolded to be in a certain wavy shape, two adjacent wave rods 41 on the support circumferential ring 4 are connected through a bending section 42, and finally, wave crests and wave troughs are formed and are staggered in the circumferential direction of the support circumferential ring 4. It will be appreciated that the stent body 1, transition section 2 and flare section 3 are each comprised of a stent circumferential ring 4. The number of carrier circumferential rings 4 in the transition section 2 may be one or more, and the number may be two or more, preferably two.

As mentioned above, the wave height of the transition section 2 being smaller than the wave height of the bell mouth body 31 and/or the wave height of the holder body 1 means that: the wave height of the carrier circumferential ring 4 in the transition section 2 is smaller than the wave height of the carrier circumferential ring 4 in the bell mouth body 31 and/or the wave height of the carrier circumferential ring 4 in the transition section 2 is smaller than the wave height of the carrier circumferential ring 4 in the carrier body 1. The fact that the stem width of the transition piece 2 is smaller than the stem width of the bell mouth body 31 and/or the stem width of the holder body 1 means that: the width of the wave rod 41 of the transition section 2 is smaller than the width of the wave rod 41 of the bell mouth body 31, and/or the width of the wave rod 41 of the transition section 2 is smaller than the width of the wave rod 41 of the bracket body 1.

For convenience of description, the wave height of the stent circumferential ring 4 in the stent body 1 is defined as a first wave height h1, the width of the wave rod 41 in the stent body 1 is defined as a first rod width b1, the wave height of the stent circumferential ring 4 in the transition section 2 is defined as a second wave height h2, the width of the wave rod 41 in the transition section 2 is defined as a second rod width b2, and the wave height of the stent circumferential ring 4 in the bell mouth body 31 is defined as a third wave height h3, and the width of the wave rod 41 in the bell mouth body 31 is defined as a third rod width b3.

The wave form design of the flare body 31 may be the same as or different from the wave form design of the holder body 1. In view of the convenience of design and process, the wave design of the bell mouth body 31 is preferably identical to the wave design of the holder body 1, and the wave design may be at least one of wave height, rod width, and head number.

The number of the connecting rods 5 at the same circumferential position in the transition section 2 is smaller than or equal to the number of heads of the support circumferential rings 4 connected with the connecting rods 5, so that the transition section 2 is in an open-loop structure or a closed-loop structure. The closed-loop structure means that the number of connecting rods 5 at the same circumferential position in the transition section 2 is equal to the number of heads of the bracket circumferential ring 4 to which the connecting rods 5 are connected, see fig. 4. The open-loop structure means that the number of connecting rods 5 at the same circumferential position in the transition section 2 is smaller than the number of heads of the circumferential ring 4 of the bracket to which the connecting rods 5 are connected, see fig. 3. If the transition section 2 is of an open-loop structure, at this time, a connecting rod 5 is connected to a part of the peak or trough of the circumferential ring 4 of the support in the transition section 2. If the transition section 2 is of an open loop structure, the situation that the vascular stent is extremely not adhered to the wall such as "king" and bending kink when released to a bent blood vessel can be reduced, and the adhesion of the transition section 2 is obviously improved.

It should be noted that, except for the stent circumferential rings 4 at the two ends of the vascular stent, the two axial sides of the stent circumferential ring 4 in the middle are respectively provided with connecting rods 5 connected with the stent circumferential rings 4, and the number of the connecting rods 5 at the two sides may be smaller than the number of heads of the corresponding stent circumferential rings 4, or the number of the connecting rods 5 at the two sides may be equal to the number of heads of the corresponding stent circumferential rings 4, or the number of the connecting rods 5 at one side may be smaller than the number of heads of the corresponding stent circumferential rings 4 and the number of the connecting rods 5 at the other side may be equal to the number of heads of the corresponding stent circumferential rings 4. In addition, the connecting rods 5 at the same circumferential position connect adjacent two of the stent circumferential rings 4, the number of the connecting rods 5 at the same circumferential position may be both smaller than the number of heads of the stent circumferential rings 4 at both sides to which they are connected, or the number of the connecting rods 5 at the same circumferential position may be both equal to the number of heads of the stent circumferential rings 4 at both ends to which they are connected, or the number of the connecting rods 5 at the same circumferential position is equal to the number of heads of the stent circumferential rings 4 at one side to which they are connected and smaller than the number of heads of the stent circumferential rings 4 at the other side to which they are connected.

When the second wave height h2 is smaller than the first wave height h1 and/or the third wave height h3, that is, the transition section 2 adopts the small-waveform support circumferential ring 4, and the support main body 1 and the bell mouth main body 31 adopt the large-waveform support circumferential ring 4. Because transition section 2 adopts the support circumference ring 4 of wavelet shape, this kind of shortwave is easier to transition the circular arc, and the adherence is better. Preferably, the first wave height h1 and/or the third wave height h3 are/is 1.2 mm-20 mm, at this time, the supporting force of the vascular stent is ensured, and meanwhile, the processing difficulty and the rejection rate are also considered. More preferably, the first wave height h1 and/or the third wave height h3 is 1.2 mm-1.8 mm. Preferably, the second wave height h2 is 0.8 mm-20.0 mm, more preferably 1.0 mm-1.6 mm, so as to balance the supporting force, flexibility and processing difficulty. The third wave height h3 and the first wave height h1 may be equal or unequal. On the basis of satisfying the physical properties of the vascular stent, in order to reduce the design and processing difficulty, the third wave height h3 and the first wave height h1 are preferably equal.

Referring to fig. 3, in a specific embodiment, the third wave height h3 and the first wave height h1 are equal and are both 1.6mm, and the ratio of the first wave height h1 to the second wave height h2 is 4:3.

When the second rod width b2 is smaller than the first rod width b1 and/or the third rod width b3, that is, the transition section 2 adopts a thin wave rod with smaller rod width, and the bracket body 1 and the bell mouth body 31 adopt thick wave rods with larger rod width. Preferably, the first rod width b1 and/or the third rod width b3 is 35 μm-120 μm, and at this time, in order to ensure that the sufficient supporting force of the vascular stent plays a role in rebound of the supporting lumen, and simultaneously reduce the size (profile) of the vascular stent after being pressed and held, so as to meet the requirement of delivery through a microcatheter. More preferably, the first bar width b1 and/or the third bar width b3 is 40 μm to 60 μm. Preferably, the second stem width b2 is 15 μm to 60 μm, more preferably 20 μm to 35 μm, for example 30 μm. The third bar width b3 and the first bar width b1 may be equal or unequal. In order to ensure uniformity of physical properties of the bracket body 1 and the bell mouth body 31 and to reduce processing difficulty, it is preferable that the first bar width b1 is equal to the third bar width b3.

Referring to FIG. 3, in one embodiment, the third bar width b3 and the first bar width b1 are equal and are each 50 μm, and the ratio of the first bar width b1 to the second bar width b2 is 5:3.

As herein, the number of heads of the stent circumferential ring 4 in the stent body 1 is defined as a first number of heads, the number of heads of the stent circumferential ring 4 in the transition section 2 is defined as a second number of heads, and the number of heads of the stent circumferential ring 4 in the bell mouth body 31 is defined as a third number of heads. The second head number is greater than or equal to the first head number, and/or the second head number is greater than or equal to the third head number, so that the flexibility of the transition section 2 is improved, and the transition section 2 between the bell mouth section 3 and the bracket main body 1 is better attached to the inner wall of the bent blood vessel in the circumferential direction. The first number of heads and the third number of heads may be equal or unequal. Optionally, the first number of heads and/or the third number of heads is 6-12.

Further, the ratio of the second number of heads to the first number of heads is 1.0 to 2.0, preferably 1.5, and/or the ratio of the second number of heads to the third number of heads is 1.0 to 2.0, preferably 1.5. If the ratio is too large, the number of heads of the transition section 2 is too large, the processing difficulty of the transition section 2 is increased or the transition section 2 cannot be cut and formed, and in addition, the heat treatment, polishing and pressing holding difficulty of the vascular stent are all increased; if the ratio is too small, the number of heads of the transition section 2 is the same as that of the bracket main body 1 or the bell mouth main body 31, and the circumferential adherence of the transition section 2 cannot be improved. In order to reduce the difference in physical properties between the stent body 1 and the flare body 31 and to reduce the difficulty in designing and processing the stent, it is preferable that the first number of heads and the third number of heads are equal.

In a specific embodiment, the number of heads of the stent circumferential ring 4 in the stent body 1 and the number of heads of the stent circumferential ring 4 in the bell mouth body 31 are both 8, and the ratio of the second number of heads to the first number of heads is 1.5.

Preferably, the number of connecting rods 5 in the transition piece 2 is smaller than the number of heads of the stent circumferential rings 4 in the stent body 1 and/or the number of connecting rods 5 in the transition piece 2 is smaller than the number of heads of the stent circumferential rings 4 in the flare body 31, enabling the transition piece 2 to better conform to the vessel wall.

The number of the connecting rods 5 at the same circumferential position in the bracket main body 1 can be smaller than or equal to the number of heads of the bracket circumferential ring 4 connected with the connecting rods 5, so that the bracket main body 1 is in an open-loop structure or a closed-loop structure. Likewise, the number of connecting rods 5 at the same circumferential position in the bell mouth body 31 may be smaller than or equal to the number of heads of the bracket circumferential ring 4 to which the connecting rods 5 are connected, so that the bell mouth body 31 is in an open-loop structure or a closed-loop structure. When the number of connecting rods 5 at the same circumferential position is smaller than the number of heads of the bracket circumferential ring 4 to which the connecting rods 5 are connected, the bracket circumferential ring 4 forms an open-loop structure. When the number of connecting rods 5 at the same circumferential position is equal to the number of heads of the bracket circumferential ring 4 to which the connecting rods 5 are connected, the bracket circumferential ring 4 forms a closed-loop structure. The adherence of the open loop structure is better than that of the closed loop structure.

Preferably, the number of connecting rods 5 at the same circumferential position in the bracket body 1 and the bell mouth body 31 is smaller than the number of heads of the bracket circumferential ring 4 to which the connecting rods 5 are connected, so that the bracket body 1 and the bell mouth body 13 are both in an open-loop structure, as shown in fig. 1 to 3. Wherein the number of heads of the respective stent circumferential rings 4 includes adjacent stent circumferential rings 4 connected at both sides in the axial direction of the connecting rod 5, the number of heads of the stent circumferential rings 4 connected at both sides of the connecting rod 5 may be the same or different, so that in some cases, the number of connecting rods 5 may be equal to the number of heads of the stent circumferential rings 4 connected at one side and smaller than the number of heads of the stent circumferential rings 4 connected at the other side. The number of connecting rods 5 at the same circumferential position is preferably smaller than the number of heads of the circumferential rings 4 of the stent connected at the two axial sides, so that the flexibility of the vascular stent is better.

In a specific embodiment, the number of connecting rods 5 at the same circumferential position in the transition section 2 is 4, which is smaller than the number of heads of the circumferential rings 4 of the support on the two axial sides connected by the connecting rods 5, i.e. the transition section 2 is in an open-loop structure.

In a specific embodiment, the number of connecting rods 5 at the same circumferential position in the bracket body 1 and the bell mouth body 31 is 3, and is also smaller than 8 heads of the bracket circumferential ring 4 connected with the connecting rods 5, that is, the bracket body 1 and the bell mouth body 31 are both in an open loop structure.

In other embodiments, as shown in fig. 4, the number of connecting rods 5 at the same circumferential position in the stent body 1 is equal to the number of heads of the stent circumferential rings 4 to which the connecting rods 5 are connected, so that the stent body 1 is in a closed-loop structure, for example, the number of connecting rods 5 at the same circumferential position in the stent body 1 and the number of heads of the stent circumferential rings 4 to which the connecting rods 5 are connected are both 8. As an embodiment, the transition section 2 and the bell mouth body 31 are both in an open loop structure, and the bracket body 1 is in a closed loop structure.

In the illustrated embodiment, both the proximal and distal ends of the stent body 1 are provided with a flare section 3. At this point, the operator (or operator) often places the distal end in a relatively straight vessel position, and the distal flare 3 can act to enhance the anchoring of the stent. In addition, the proximal implantation position of the vascular stent is often affected by factors such as the bending degree of the blood vessel, the deviation of the stent shrinkage rate and the like, and the possibility of deviation from the preoperative scheme of an operator (operator) exists, so that the probability of releasing the proximal end of the vascular stent to a vascular tortuosity section is higher, and the poor adherence caused by poor release position of the vascular stent can be compensated to a certain extent by the horn mouth design of the proximal end.

The connecting rod 5 may be of various suitable shapes, for example, the connecting rod 5 may be a straight rod, a curved rod, a broken line rod, and the curved rod and the broken line rod may be such as: s-shape, omega-shape, W-shape, etc. In order to reduce the shortening rate of the vascular stent, the connecting rod 5 is preferably a straight rod. The connecting rod 5 can be integrally cut and formed when the pipe is cut. In this embodiment, the connecting rod 4 is used as a straight rod for illustration.

The material for preparing the vascular stent can be a metal elastic material or a shape memory alloy material with a self-expansion effect, the shape memory alloy material is generally nickel-titanium alloy, or a traditional metal elastic material commonly used for a spherical stent such as stainless steel, cobalt-chromium alloy and the like, or a polymer degradable material commonly used for a degradable absorption stent such as polylactic acid, polypropylene ester and the like. It should be noted that the material for preparing the vascular stent is a common medical material understood by those skilled in the art, and thus the material for preparing the vascular stent is not particularly limited in this application.

In summary, the vascular stent provided in this embodiment has good radial support performance and good opening performance, and the adhesion performance of the transition section 2 between the bell mouth section 3 of the vascular stent and the stent body 1 is good when released to a tortuous blood vessel.

[ example two ]

Fig. 5 is a schematic structural diagram of a vascular stent according to a second embodiment of the present utility model, and fig. 6 is a partially enlarged view of a transition section 2 between a stent body 1 and a flare section 3 according to a second embodiment of the present utility model. The following description will be mainly directed to the differences from the first embodiment, and the same parts will not be described in detail, but reference is made to the first embodiment.

As shown in fig. 5 and 6, the vascular stent of the present embodiment is of a one-sided flare design, in which the flare section 3 is provided only at the proximal end of the stent body 1, at this time, a part of the peaks at the distal end of the stent body 1 protrude in the axial direction to form protruding portions 11, the protruding portions 11 being mountable with a developing structure, and in other cases, all the peaks at the distal end of the stent body 1 are free of protruding portions 11 in the axial direction. A transition section 2 is arranged between the proximal flare section 3 and the bracket main body 1. Optionally, the third wave height and the first wave height are both 1.6mm, and the second wave height is 1.2mm. In this embodiment, the first rod width, the second rod width and the third rod width are equal, and the number of first heads, the number of second heads and the number of third heads are all 8. In addition, the transition section 2, the bracket body 1 and the bell mouth body 31 are all of an open-loop structure. It should be understood that when the vascular stent is over-bent, a large curved side and a small curved side are formed, the path length difference between the large curved side and the small curved side leads to the increase of the adhesion difficulty, and the degree of freedom of the curved section wave rod of the open loop structure is higher, so that the adhesion effect is better.

Finally, the embodiment of the utility model also provides a preparation method of the vascular stent, which is used for manufacturing the vascular stent provided by any embodiment of the application, and comprises the following steps:

providing an original tube, cutting the original tube to obtain a vascular stent comprising a stent main body, a bell mouth section and an excess section, and enabling the vascular stent to have at least one of the following characteristics in the cutting process:

the wave height of the transition section is smaller than the wave height of the bracket main body and/or the wave height of the horn mouth section;

the rod width of the transition section is smaller than the rod width of the bracket main body and/or the rod width of the bell mouth section;

the number of heads of the transition section is not smaller than that of the bracket main body and/or that of the bell mouth section.

In summary, the utility model improves the adherence performance of the transition section by adjusting the waveform structure of the transition section, at least one structure of the wave height, the rod width and the head number of the transition section can be adjusted to improve the adherence performance of the transition section, and the number of connecting rods of the transition section can be further adjusted, so that the transition section has good adherence effect, and when the vascular stent is released into a blood vessel with a shape-changeable and tortuous, the risk of long-term thrombosis of the vascular stent can be effectively reduced and the occurrence probability of restenosis in the stent can be reduced under the condition that the adherence effect of the transition section is good.

It should be noted that, in the present description, each embodiment is described in a progressive manner, and each embodiment is mainly described in a different manner from other embodiments, and identical and similar parts between the embodiments are all enough to refer to each other. For the system disclosed in the embodiment, the description is relatively simple because of corresponding to the method disclosed in the embodiment, and the relevant points refer to the description of the method section.

It should be further noted that although the present utility model has been disclosed in the preferred embodiments, the above embodiments are not intended to limit the present utility model. Many possible variations and modifications of the disclosed technology can be made by anyone skilled in the art without departing from the scope of the technology, or the technology can be modified to be equivalent. Therefore, any simple modification, equivalent variation and modification of the above embodiments according to the technical substance of the present utility model still fall within the scope of the technical solution of the present utility model.

It should be further understood that the terms "first," "second," "third," and the like in this specification are used merely for distinguishing between various components, elements, steps, etc. in the specification and not for indicating a logical or sequential relationship between the various components, elements, steps, etc., unless otherwise indicated.

Claims (22)

1. A vascular stent comprising a stent body, a flare section and a transition section between the stent body and the flare section, characterized in that the vascular stent meets at least one of the following conditions:

the wave height of the transition section is smaller than the wave height of the bracket main body and/or the wave height of the horn mouth section;

the rod width of the transition section is smaller than the rod width of the bracket main body and/or the rod width of the bell mouth section;

the number of heads of the transition section is not smaller than that of the bracket main body and/or that of the bell mouth section.

2. The vascular stent of claim 1, wherein the vascular stent has a plurality of stent circumferential rings arranged in sequence along the axial direction thereof, the stent circumferential rings being composed of waverods connected in sequence end to end; in the axial direction of the vascular stent, the peaks and the troughs of any two adjacent circumferential rings of the stent are connected through connecting rods, and the number of the connecting rods at the same circumferential position in the transition section is smaller than or equal to the number of heads of the circumferential rings of the stent connected by the connecting rods.

3. The vascular stent of claim 2, wherein the number of connecting rods at the same circumferential position in the transition section is less than the number of stent circumferential rings in the stent body and/or the number of stent circumferential rings in the flare section.

4. The vascular stent of claim 2, wherein the number of connecting rods at the same circumferential position in the stent body is less than or equal to the number of heads of the stent circumferential rings to which the connecting rods are connected, and/or the number of connecting rods at the same circumferential position in the flare section is less than or equal to the number of heads of the stent circumferential rings to which the connecting rods are connected.

5. The vascular stent of claim 2, wherein the number of connecting rods at the same circumferential location is less than the number of circumferential rings of the stent to which the axial sides of the connecting rods are connected.

6. The vascular stent of claim 1 or 2, wherein the stent body has a wave height of a first wave height and the horn section has a wave height of a third wave height, the first wave height and the third wave height being equal or unequal.

7. The vascular stent of claim 6, wherein the first wave height and/or the third wave height is 1.2mm to 20mm.

8. The vascular stent of claim 7, wherein the first wave height and/or the third wave height is 1.2mm to 1.8mm.

9. The vascular stent of claim 1 or 2, wherein the transition section has a wave height of a second wave height of 0.8mm to 20.0mm.

10. The vascular stent of claim 9, wherein the second wave height is 1.0mm to 1.6mm.

11. The vascular stent of claim 1 or 2, wherein the stent body has a first stem width and the flare section has a third stem width, the first and third stem widths being equal or unequal.

12. The vascular stent of claim 11, wherein the first stem width and/or the third stem width is 35 μιη to 120 μιη.

13. The vascular stent of claim 12, wherein the first stem width and/or the third stem width is 40 μιη to 60 μιη.

14. The vascular stent of claim 1 or 2, wherein the transition section has a stem width of a second stem width of 15 μιη to 60 μιη.

15. The vascular stent of claim 14, wherein the second stem width is 20 μιη to 35 μιη.

16. The vascular stent of claim 1 or 2, wherein the stent body has a first number of apices, the horn section has a third number of apices, and the first number of apices is equal to or unequal to the third number of apices.

17. The vascular stent of claim 16, wherein the transition section has a second number of heads, wherein the ratio of the second number of heads to the first number of heads is 1.0 to 2.0, and/or wherein the ratio of the second number of heads to the third number of heads is 1.0 to 2.0.

18. The vascular stent of claim 17, wherein the ratio of the second number of heads to the first number of heads is 1.5 and/or the ratio of the second number of heads to the third number of heads is 1.5.

19. A vascular stent as claimed in claim 1 or claim 2, wherein only the proximal end of the stent body is provided with the flare section, or wherein both the proximal and distal ends of the stent body are provided with the flare section.

20. The vascular stent of any of claims 2-5, wherein the connecting rod is a straight rod, a curved rod, or a broken line rod.

21. The vascular stent of any of claims 1-5, wherein the vascular stent material is an elastic material, a shape memory alloy material, or a degradable material.

22. The vascular stent of any of claims 1-5, wherein the flare section includes only a flare body or the flare section includes a flare body and a flare tip, a portion of the peak at the end of the flare body distal from the transition section protruding axially to form the flare tip.

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