A vascular stent

Abstract

The present invention discloses a vascular stent, which comprises a plurality of single-ring stents arranged at intervals along the axial direction. While extending circumferentially, the single-ring stents undulate axially in a wavy shape; a plurality of connectors, with adjacent two single-ring stents connected by the connectors; wherein, the connectors include two circumferential connectors and at least one axial connector; one circumferential connector connects the peak of one single-ring stent circumferentially, and the other circumferential connector connects the valley of another single-ring stent circumferentially; the axial connector connects the peaks or valleys of adjacent two single-ring stents or the circumferential connectors axially. The vascular stent of the present invention has the characteristics of being able to increase the radial and axial support forces, effectively preventing eccentricity and collapse, being easy to produce various mechanical property specifications, having excellent bending performance, and a small shortening rate.

Description

Technical Field

[0001] The present invention relates to the technical field of biomedical engineering, and in particular to a blood vessel stent. Background Art

[0002] Thoracic Endovascular Aortic Repair (TEVAR) is a minimally invasive interventional treatment procedure that involves percutaneous puncture of the femoral artery, and the delivery of interventional devices such as stent grafts to the lesion site along the femoral artery under the guidance of imaging equipment, thereby isolating the dissection site in the vascular lumen. It is widely used in clinical practice because of its advantages such as less trauma, faster recovery, and avoidance of some complications of surgical operations.

[0003] The aorta has a certain taper in its axial direction, with a larger diameter at the proximal end and a smaller diameter at the distal end. After TEVAR, stent-induced new entry (SINE) may occur. SINE refers to the incomplete matching of the straight-cylindrical stent graft with the tapered vascular morphology. After the stent graft is inserted, the distal end of the stent opens excessively, generating a large shear stress on the aortic dissection diaphragm, thereby inducing a new tear. Usually, before the stent graft is released during TEVAR, a restrictive bare stent (RBS) is pre-placed at the distal end of the stent graft to limit the excessive opening of the distal end of the stent graft and prevent the occurrence of SINE.

[0004] Existing aortic stent grafts and restrictive stents have the following defects:

[0005] 1. The exposed area at the end of the existing partial covered stent may compress the inner wall of the blood vessel and increase the risk of endothelial rupture. The existing partial covered stents are usually made of multiple stent rings sewn together with a polymer film. A small section of the exposed stent ring will extend outward from the proximal or distal end of the covered stent to hook the delivery system and adapt to the loading, pushing and releasing of the delivery system. However, the blood vessels will peristalsis with the beating of the heart. When the covered stent is completely released at the lesion site, the exposed area of ​​the covered stent will squeeze against the inner wall of the blood vessel and even penetrate the weak endothelial membrane of the lesion area.

[0006] 2. The stent vertices at both ends of the bare stent may compress the inner wall of the blood vessel, increasing the risk of intimal rupture. The two ends of the bare stent are similar to the exposed sections of the above-mentioned covered stent. When the bare stent is completely released at the lesion site, the two ends of the bare stent will squeeze the inner wall of the blood vessel with the peristalsis of the blood vessel, and even penetrate the weak intima of the lesion area.

[0007] 3. The shortening rate of the stent is relatively large, that is, the length of the tubular stent in its axial direction is prone to decrease. The reason for this phenomenon is mostly due to the poor way of connecting the ring stents. Reason for shortening one: After the existing stent is axially stressed, the connector is extremely easy to reverse axially, causing the stent to shorten axially. Moreover, the greater the axial length of the connector, the greater the shortening rate. Reason for shortening two: The existing stents are mostly composed of multiple independent single-ring stents connected together, and the connectors are metal wires or polymer wires, etc. By winding or knotting the silk thread at the wave crests and troughs, multiple single-ring stents are then connected into a complete stent. However, the silk thread knots are prone to slide on the wave rods of the stent. When the knots slide from the wave crests and troughs to the middle section of the wave rod, the stent not only shortens as a whole, but also its shape will change unpredictably, thereby affecting the performance of the overall stent.

[0008] 4. The bending performance of some bare stents is poor. After some existing bare stents are bent greatly, the bending cross-section of the stent is distorted, and the cross-sectional shape changes from circular to an elliptical shape with acute angles. The major axis of the ellipse is larger than the inner diameter of the blood vessel at the diseased site, and the acute angles may scratch the inner wall of the blood vessel. At the same time, after some existing bare stents are bent greatly, internal folding occurs at the small bend, and the cross-sectional area becomes smaller, resulting in the outer surface of the stent being unable to fit well with the inner wall of the blood vessel.

[0009] 5. At present, there are few vascular stents specifically used for treating Debakey type II, especially for Debakey type II without the need for branch vessel reconstruction and the dissection not involving the aortic arch. Since the ascending aorta is short and close to the heart, to prevent the vascular stent inserted into this area from falling off, the stent needs to have a certain length to span the aortic arch and complete anchoring. If traditional covered stents are used for interventional treatment, the polymer film will block the blood supply of some branches of the aortic arch, so it is necessary to open holes in the film and complete the precise adaptation of the holes to the branch vessels, which greatly increases the difficulty of the surgical operation.

[0010] 6. The radial support force distribution of the whole of some bare stents is uneven in the axial direction, that is, the radial support forces of the single-ring stent and the connector are quite different. The existing stent's radial support force is provided by the single-ring stent, and the bending performance is provided by the silk thread of the connector, while the silk thread has almost no radial support force. This results in uneven radial support force distribution of the overall stent. The single-ring stent must have sufficient radial support force to stably anchor the overall stent in the blood vessel without sliding. Therefore, the pressure generated by the single-ring stent on the inner wall of the blood vessel is much greater than that of the connector part, and the inner wall of the patient's blood vessel is very weak. The single-ring stent generating a large pressure is very likely to cause secondary damage to the inner wall of the blood vessel.

[0011] 7. The mechanical property specifications of some existing bare stents are relatively single. According to the structural design and manufacturing technology of some existing stents, only the mechanical properties of the single-ring stent can be adjusted, and the mechanical properties of the single-ring stent mainly depend on two parts: the size of the wave rod cross-section and the performance of the manufacturing material itself. The size specification of the wave rod cross-section is relatively fixed, and the mechanical properties of the material itself need to be debugged through complex processes. Therefore, based on the structural design and manufacturing technology of the existing stent, it is very difficult to produce stents with a variety of different mechanical properties.

[0012] 8. Some existing bare stents are prone to phenomena such as eccentricity and collapse of the stent ring. After some existing bare stents are implanted, the probability of failures such as separation, fracture, and dislocation of the stent ring is as high as 9.2%. Especially for the bare stent part extending to the abdominal aorta, it is extremely prone to phenomena such as eccentricity and collapse, which is caused by the lack of radial support force and axial support of the stent. Summary of the Invention

[0013] In view of the above-mentioned disadvantages of the prior art, the purpose of the present invention is to provide a vascular stent that can increase radial and axial support forces, effectively prevent eccentricity and collapse, is easy to produce a variety of mechanical property specifications, has excellent bending performance, and a small shortening rate.

[0014] To achieve the above object and other related objects, the present invention provides a vascular stent, which includes:

[0015] A plurality of single-ring stents arranged at intervals along the axis, and the single-ring stents extend circumferentially and undulate axially in a wave shape;

[0016] A plurality of connectors, and adjacent two single-ring stents are connected by the connectors;

[0017] Wherein, the connector includes two circumferential connectors and at least one axial connector;

[0018] One of the circumferential connectors connects the wave crest of one of the single-ring stents in the circumferential direction, and the other circumferential connector connects the wave trough of the other single-ring stent in the circumferential direction;

[0019] The axial connector connects the wave crests or wave troughs of two adjacent single-ring stents or the circumferential connectors in the axial direction.

[0020] In an optional embodiment of the present invention, the material of the single-ring stent is a shape memory alloy.

[0021] In an optional embodiment of the present invention, the single-ring stent includes a wave crest, a wave trough, and a wave rod connecting the wave crest and the wave trough, and the wave rod is tangent or non-tangent to the wave crest / wave trough.

[0022] In an alternative embodiment of the present invention, the relative positions of several of the single-ring stents are the same or different.

[0023] In an alternative embodiment of the present invention, the material of the connecting body is a shape memory alloy.

[0024] In an alternative embodiment of the present invention, the connecting body is in a mesh form.

[0025] In an alternative embodiment of the present invention, the axial connecting body is completely distributed circumferentially.

[0026] In an alternative embodiment of the present invention, the vascular stent further includes a membrane, and the membrane is attached to the single-ring stent and / or the connecting body.

[0027] In an alternative embodiment of the present invention, the circumferential connecting body is annular, and the circumferential connecting body is connected to the trough / crest of the single-ring stent by winding.

[0028] In an alternative embodiment of the present invention, the circumferential connecting body is a single-strand metal wire or a multi-strand twisted metal wire.

[0029] In an alternative embodiment of the present invention, the circumferential connecting body includes a first knot, and the first knot is a knot wound around the crest or trough of the single-ring stent.

[0030] In an alternative embodiment of the present invention, the axial connecting body is wound around the crest / trough and passes through the gap of the first knot.

[0031] In an alternative embodiment of the present invention, the number of the first knots of one circumferential connecting body is greater than or equal to half of the number of the crests / troughs of one single-ring stent.

[0032] In an alternative embodiment of the present invention, the circumferential connecting body further includes a second knot, and the second knot is a knot formed by the circumferential connecting body winding itself and located between adjacent crests or troughs of the single-ring stent. The axial connecting body is intertwined and wound around the crest, the first knot, the second knot, the trough, and the first knot.

[0033] In an alternative embodiment of the present invention, the axial connecting body is wound in the gap of the second knot.

[0034] In an alternative embodiment of the present invention, the circumferential connecting body is provided with a first knot on each crest / trough of the single-ring stent, and a second knot is provided between each adjacent crest / trough of the single-ring stent. The axial connecting body is wound around each first knot and the second knot once.

[0035] In an alternative embodiment of the present invention, the axial connectors include at least two. One axial connector is in an "N" shape, and the other axial connector is in a reverse "N" shape.

[0036] In an alternative embodiment of the present invention, the axial connectors are evenly distributed along the circumferential direction of the vascular stent.

[0037] In an alternative embodiment of the present invention, the cross-sectional dimension of the metal wire of the connector is smaller than the cross-sectional dimension of the wire of the single-ring stent.

[0038] In an alternative embodiment of the present invention, the ratio of the cross-sectional dimension of the wire of the single-ring stent to the cross-sectional dimension of the metal wire of the connector is between 2 and 20.

[0039] The two ends of the vascular stent of the present invention can be attached with a membrane, which can relieve the compression of the free apex at the end of the stent on the inner wall of the blood vessel and reduce the risk of intimal rupture.

[0040] The designed structure of the connector of the vascular stent of the present invention can greatly reduce the implantation shortening rate of the vascular stent.

[0041] The designed structure of the connector of the vascular stent of the present invention can provide a certain radial supporting force, ensuring the stability of the stent while guaranteeing the overall stent anchoring performance.

[0042] The designed structure of the connector of the vascular stent of the present invention can provide a certain axial supporting force, which can stabilize each single-ring stent.

[0043] After the vascular stent of the present invention is greatly bent, the cross-section of the arch part of the stent has a small distortion, and the reduction amount of the cross-sectional area of the arch part of the stent is small, and a good circular cross-section of the arch part can be maintained.

[0044] The combination of the local membrane covering of the vascular stent of the present invention and the excellent bending performance of the stent enables the vascular stent of the present invention to be used for the interventional treatment of Debakey type II without the need for branch vessel reconstruction and the dissection not involving the aortic arch.

[0045] The vascular stent of the present invention can be used as a restrictive bare stent to limit the excessive opening of the distal end of the covered stent and prevent the occurrence of SINE.

[0046] The vascular stent of the present invention can effectively relieve the problems of eccentricity and collapse of some existing bare stents.

[0047] The manufacturing technology of the vascular stent of the present invention can easily change the overall mechanical properties of the stent and produce more stents with different mechanical property specifications. BRIEF DESCRIPTION OF THE DRAWINGS

[0048] Figure 1Shows a schematic structural diagram of the vascular stent of the present invention.

[0049] Figure 2 Shows a three-dimensional structural schematic diagram of the single-ring stent of the vascular stent of the present invention.

[0050] Figure 3 Shows a front view of the single-ring stent of the vascular stent of the present invention.

[0051] Figure 4 Shows a schematic structural diagram when the lengths of the wave rods of the single-ring stent of the vascular stent of the present invention are not equal.

[0052] Figures 5a - 5c Shows a schematic diagram of three optional forms of the wave crest or wave trough of the vascular stent of the present invention.

[0053] Figure 6 Shows a schematic diagram of the relative positions of the single-ring stents of the vascular stent of the present invention.

[0054] Figure 7 Shows a three-dimensional structural schematic diagram of the connecting body of the vascular stent of the present invention.

[0055] Figure 8 Shows a front view of the connecting body of the vascular stent of the present invention.

[0056] Figure 9 Shows a winding schematic diagram of the connecting body of the vascular stent of the present invention.

[0057] Figures 10a - 10e Shows five optional schematic diagrams of the grid form of the connecting body of the vascular stent of the present invention.

[0058] Figure 11 Shows a schematic structural diagram of the film covering of the vascular stent of the present invention.

[0059] Figures 12a - 12c Respectively shows a comparison schematic diagram of a traditional covered stent, a traditional bare stent and the vascular stent of the present invention.

[0060] Figure 13 Shows a loading schematic diagram of a traditional covered stent.

[0061] Figure 14 Shows a loading schematic diagram of the vascular stent of the present invention.

[0062] Figure 15a Shows a schematic diagram of the connecting body of some existing stents reversing axially.

[0063] Figure 15b Shows a schematic diagram of the connecting body of some existing stents sliding along the wave crest or wave trough of the single-ring stent under the action of an axial force.

[0064] Figure 15c It shows a schematic diagram of the circumferential center of each single-ring stent of an existing partial bare stent deflecting.

[0065] Figure 16a and 16b respectively show a comparative schematic diagram of an existing partial stent and the vascular stent of the present invention in a large bending form.

[0066] Figure 17 It shows a schematic diagram of the vascular stent of the present invention for treating DeBakey type II dissection.

[0067] Figure 18 It shows a schematic diagram of the vascular stent of the present invention used as a restrictive bare stent.

[0068] Figure 19a and 19b respectively show schematic diagrams of an existing partial restrictive bare stent being eccentric and collapsing after intervention.

[0069] Label description

[0070] Vascular stent 100, existing restrictive bare stent 100', non-covered section 100a, covered section 100b, single-ring stents 10, 10', peak 101, wave rod 102, trough 103, sleeve 104, connectors 20, 20', 21 circumferential connectors, first circumferential connector 211, first knot 2111, second knot 2112, second circumferential connector 212, axial connector 22, first axial connector 22a, second axial connector 22b, film 30, sheath 40, fixed claw head 50, inner core tube 60, ascending aorta 701, aortic arch 702, descending aorta 703, branch vessel 704, dissection 705, abdominal aorta 706. Detailed implementation manners

[0071] The following uses specific specific examples to illustrate the implementation manners of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. The present invention can also be implemented or applied through other different specific implementation manners. Various details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of the present invention.

[0072] Please refer to Figures 1 - 1 9. It should be noted that the illustrations provided in this embodiment only schematically illustrate the basic concept of the present invention. Therefore, only the components related to the present invention are shown in the drawings, rather than being drawn according to the number, shape, and size of the components in actual implementation. The types, quantities, and proportions of the components in actual implementation can be arbitrarily changed, and the component layout type may also be more complex.

[0073] For ease of description, the following professional terms used in this text are explained:

[0074] Small bend: Blood vessels, stents, etc. are circular tubular in shape. When they are bent, the side with a smaller bending radius is the small-bend side.

[0075] Large bend: Blood vessels, stents, etc. are circular tubular in shape. When they are bent, the side with a larger bending radius is the large-bend side.

[0076] Proximal end: Arterial blood vessels that originate from the heart gradually branch into capillaries and then gradually converge into venous blood vessels and return to the heart. For any segment of these blood vessels, the end closer to the heart is called the proximal end.

[0077] Distal end: Arterial blood vessels that originate from the heart gradually branch into capillaries and then gradually converge into venous blood vessels and return to the heart. For any segment of these blood vessels, the end farther from the heart is called the distal end.

[0078] Axial direction: Blood vessels, interventional stents, etc. are circular tubular in shape. If they are regarded as cylinders, the axis of rotation of the cylinder is defined as the axial direction.

[0079] Radial direction: The "radial direction" is perpendicular to the "axial direction", that is, the radius or diameter direction of the circular end face of the cylinder. The radial direction is perpendicular to the axial direction in space.

[0080] Circumferential direction: The "circumferential direction" is the circumferential direction, which together with the "axial direction" and the "radial direction" constitutes three orthogonal directions of the cylindrical coordinate system.

[0081] The present invention introduces an interventional vascular stent 100 (which can also be referred to as a vascular stent). Among them, Figure 1 The structural schematic diagram of the vascular stent 100 of the present invention is shown. As Figure 1 shown, as the entire prosthesis for interventional treatment, the vascular stent 100 is an assembly composed of three components, namely, a single-ring stent 10, a connecting body 20, and a film 30, through a certain process.

[0082] It should be noted that in some embodiments, the vascular stent 100 may not include the film 30, but is directly an assembly composed of the single-ring stent 10 and the connecting body 20 through a certain process. Hereinafter, the case where the vascular stent 100 includes the single-ring stent 10, the connecting body 20, and the film 30 will be taken as an example for description.

[0083] As Figure 1As shown, in the present invention, the vascular stent 100 is composed of multiple rings of single-ring stents 10 and multiple rings of connectors 20. The overall vascular stent is a tubular network structure. The membrane 30 is a layer of flexible film material attached to the single-ring stent 10 or the connector 20. The multiple rings of single-ring stents 10 are arranged in parallel at intervals from the proximal end to the distal end of the vascular stent 100. There is one ring of connector 20 between every two adjacent rings of single-ring stents 10, that is, the single-ring stents 10 and the connectors 20 are distributed at intervals along the axial direction of the vascular stent 100. It should be noted that in some embodiments, the connector 20 may not be provided between two adjacent single-ring stents 10 connected by the membrane 30. The single-ring stent 10 has better bending resistance and supporting performance than the connector. When the vascular stent 100 is implanted into the diseased site, multiple single-ring stents 10 can be relied on to anchor and support at the diseased site to prevent the vascular stent 100 from shifting. The connector 20 has better bending performance and flexibility than the single-ring stent 10. When the vascular stent 100 is transported in a curved blood vessel and placed in a curved blood vessel, multiple connectors 20 can be relied on to bend. The membrane 30 has high sealing performance. When the vascular stent 100 is implanted into the diseased site, the membrane 30 can cover the diseased area and seal the diseased area, preventing the blood in the aorta from entering the media of the blood vessel from the tear of the intima, and preventing the continuous separation of the intima and media of the blood vessel, thereby alleviating the disease condition.

[0084] Figure 2 The three-dimensional structural schematic diagram of the single-ring stent 10 of the present invention is shown. Figure 3 The front view of the single-ring stent 10 of the present invention is shown. Please refer to Figure 2 and Figure 3 In the present invention, the single-ring stent 10 is one of the components constituting the vascular stent 100, and the vascular stent 100 includes several single-ring stents 10. Each single-ring stent 10 extends circumferentially along the vascular stent 100 to form a closed ring, and while extending circumferentially, it undulates along the axial direction of the vascular stent 100, that is, the single-ring stent 10 is wavy in its axial direction.

[0085] In the present invention, the single-ring stent 10 is formed by bending and heat-treating a metal wire with a circular cross-section into a circular or approximately circular ring. While the single-ring stent 10 extends circumferentially, it undulates axially in a wavy shape. The material for making the single-ring stent 10 is a shape memory alloy, such as nickel-titanium alloy (NiTi). The overall height H1 of the single-ring stent 10 ranges from 5 to 20 mm, such as 5 mm, 10 mm, 15 mm or 20 mm; the overall diameter D1 of the single-ring stent 10 ranges from 10 to 50 mm, such as 10 mm, 20 mm, 30 mm, 40 mm or 50 mm; the cross-sectional diameter d1 of the metal wire of the single-ring stent 10 ranges from 0.1 to 1 mm, such as 0.1 mm, 0.2 mm, 0.4 mm, 0.6 mm, 0.8 mm or 1 mm.

[0086] In an alternative embodiment, the cross-section of the metal wire of the single-ring stent 10 can also be square, trapezoidal or other suitable shapes. When the cross-section of the metal wire of the single-ring stent 10 is square, the diagonal dimension of the square is defined as d1, and its range is 0.1 to 1 mm, such as 0.1 mm, 0.2 mm, 0.4 mm, 0.6 mm, 0.8 mm or 1 mm.

[0087] In an alternative embodiment, the single-ring stent 10 can also be made by laser cutting a metal tube and then expanding and shaping it through heat treatment. In an alternative embodiment, the single-ring stent 10 can also be made in one step by 3D metal printing.

[0088] Please refer to Figure 2 and Figure 3 , in the present invention, the single-ring stent 10 includes a wave crest 101, a wave trough 103 and a wave rod 102 connecting the wave crest 101 and the wave trough 103. One wave crest 101 and two adjacent wave rods 102 form a wave. The wave crest 101 and the wave trough 103 are relative. When the single-ring stent 10 is inverted axially, the wave crest becomes the wave trough and the wave trough becomes the wave crest. The number of waves of a single-ring stent 10 is not fixed and should be set according to the values of the overall height H1 of the single-ring stent 10 and the overall diameter D1 of the single-ring stent 10 to conform to the aortic physiological anatomical structure. As an example, the number of waves of a single-ring stent 10 is between 3 and 12, where Figure 2 shows a case where the number of waves of the single-ring stent 10 is 6.

[0089] In the present invention, the radius R of the transition fillet between the wave crest 101 or the wave trough 103 ranges from 0 to 5 mm, such as 0 mm (corresponding to the case where two adjacent wave rods 102 are directly connected without a fillet), 1 mm, 2 mm, 3 mm, 4 mm or 5 mm. The several R values of a single-ring stent 10 are not necessarily the same, that is, the sizes of the several wave crests 101 or wave troughs 103 of the same single-ring stent 10 may be the same or different. The size of each R value should be set according to the requirements of functions such as the later crimping of the vascular stent 100. As an example, Figure 3 shows the case where the sizes of the several wave crests 101 or wave troughs 103 of the same single-ring stent 10 are the same.

[0090] In the present invention, the opening angle of the wave crest 101 (i.e., the angle α between two adjacent wave rods 102) ranges from 10° to 70°, such as 10°, 20°, 30°, 40°, 50°, 60° or 70°. The opening angles α of the several wave crests 101 in the same single-ring stent 10 may be the same or different. The size of each α value should be set according to the requirements of functions such as the later crimping of the vascular stent 100.

[0091] Figure 2 And Figure 3 shows the case where all the wave rods 102 of the single-ring stent 10 are tangent to their adjacent wave crests 101 or wave troughs 103, and all the α values are the same acute angle (of course, it can also be an obtuse angle). It can be understood that the wave rod 102 and the wave crest 101 or the wave trough 103 can also adopt one of the wave forms such as Figures 5a - 5c . Among them, in Figure 5a , the wave rod 102 is not tangent to the wave crest 101 or the wave trough 103, and α is an acute angle, and the wave crest 101 or the wave trough 103 presents a major arc shape; in Figure 5b , the wave rod 102 is not tangent to the wave crest 101 or the wave trough 103, and α is an obtuse angle, and the wave crest 101 or the wave trough 103 presents a minor arc shape; in Figure 5c , the wave crest 101 or the wave trough 103 can be in the shape of "M" or "W", etc.

[0092] Please refer to Figures 2 - 4 as shown. In the present invention, the wave rod 102 is a straight rod connecting the wave crest 101 and the wave trough 103. The length L1 of the wave rod 102 ranges from 1 to 30 mm, and the length L1 of the wave rod 102 ranges from 1 to 30 mm, such as 1 mm, 5 mm, 10 mm, 15 mm, 20 mm, 25 mm or 30 mm. In the same single-ring stent 10, the lengths L1 of several wave rods 102 may be the same or different. As an example, Figure 3 shows the case where the lengths L1 of all the wave rods 102 of each single-ring stent 10 are equal. As an example, Figure 4A schematic diagram of the structure of a single-ring stent 10 is shown when the lengths L1 of the wave rods 102 are unequal. When the lengths L1 of the wave rods 102 are unequal, the waves in the single-ring stent 10 present shapes of different sizes. Waves of different sizes have different bending properties, which can better adapt to curved blood vessels. It should be noted that in addition to the straight rod shape, the wave rod 102 can also be in the shape of an "S"-shaped rod, a "Z"-shaped rod, etc.

[0093] See also Figure 2 In the present invention, the single-ring stent 10 further includes a sleeve 104 , which may be a thin-walled metal sleeve having an inner diameter slightly larger than the cross-sectional diameter d1 of the metal wire of the single-ring stent 10 . Figure 2 The single-ring stent 10 includes two sleeves 104. One sleeve 104 is used to connect the ends of the metal wires of the single-ring stent 10. By clamping or welding, one metal wire becomes a ring connected end to end. The other sleeve 104 is inserted into the wave rod 102, and the wire ends of the connector 20 are buried in the sleeve 104. The sleeve 104 is clamped to fix the sleeve 104 and the wire ends on the wave rod 102. The sleeve 104 is made of suitable metals such as stainless steel and NiTi. It is understandable that only one sleeve 104 can be used to connect the ends of the metal wires of the single-ring stent 10, and the wire ends of the connector 20 are trimmed instead of being buried in the sleeve 104.

[0094] It is understandable that when the single-ring stent 10 is manufactured by cutting or metal printing, the sleeve 104 is not required.

[0095] like Figure 6 As shown, the relative positions of the multiple single-ring stents 10 in the vascular stent 100 can be the same or different. Figure 6 In the middle and lower elliptical area, the wave crests 101 of the two adjacent single-ring stents 10 are staggered, and the wave crest 101 of one single-ring stent 10 is located between the two wave crests 101 of the other single-ring stent 10. For example, of the two adjacent single-ring stents 10, the wave crest 101 of one single-ring stent 10 may be vertically opposite to the wave trough 103 of the other single-ring stent 10 in the axial direction; Figure 6 In the upper middle elliptical area, between two adjacent single-ring brackets 10, the wave crest 101 of one single-ring bracket 10 may be axially inclined relative to the wave trough 103 of the other single-ring bracket 10, that is, the wave crest 101 of one single-ring bracket 10 is located between the two wave troughs 103 of the other single-ring bracket 10, for example, the wave crests 101 of the two adjacent single-ring brackets 10 are aligned.

[0096] Figure 7 shows a three-dimensional schematic diagram of a connector 20 of the present invention, Figure 8 FIG. 2 shows a front plan view of a connector 20 of the present invention. Figure 9The winding schematic diagram of the connector of the vascular stent of the present invention is shown.

[0097] Please refer to Figures 7 - 9 , in the present invention, the connector 20 is composed of several cord-like flexible bodies. The several cord-like flexible bodies are wound around a plurality of single-ring stents 10 to play a role in connecting adjacent single-ring stents 10. At the same time, the several cord-like flexible bodies will also be intertwined with each other to jointly form a connector 20. Among them, the cord-like flexible body is, for example, a metal wire, and the material of the connector 20 is a shape memory alloy, such as nickel-titanium alloy (NiTi). The axial cross-sectional dimension d2 of the metal wire used for the connector 20 is smaller than the axial cross-sectional dimension d1 of the metal wire used for the single-ring stent 10, and d1:d2 = 2 - 20, such as 2, 5, 8, 11, 14, 17, 20. The connector 20 includes a circumferential connector 21 and an axial connector 22.

[0098] Please refer to Figures 7 - 9 , in the present invention, the circumferential connector 21 includes a first circumferential connector 211 and a second circumferential connector 212. The first circumferential connector 211 is a metal wire that is wound around the trough 103 or peak 101 of the single-ring stent 10 in sequence in the circumferential direction. Through bending, winding, and heat treatment setting of the metal wire, its circumferential shape is the same as that of the single-ring stent 10, and it is a circular or approximately circular loop. The first circumferential connector 211 can be a single-strand metal wire or a multi-strand twisted metal wire.

[0099] The first circumferential connector 21 includes a first knot 2111 formed by winding around the peak 101 or trough 103 and a second knot 2112 that winds around itself and is located between adjacent peaks 101 or troughs 103. The first knot 2111 can be any suitable knot form such as a Prusik knot, a single knot, a figure-eight knot, a double fisherman's knot, or a direct loop; the second knot 2112 can be any suitable knot form such as a Prusik knot, a single knot, a figure-eight knot, a double fisherman's knot, or a direct loop.

[0100] The number of the first knots 2111 on each first circumferential connector 21 is not limited, nor is it limited that they must be evenly distributed circumferentially, that is, the first knots 2111 may not be tied on some of the peaks 101 or troughs 103. The maximum number of the first knots 2111 is the same as the number of the peaks 101 or troughs 103, but the minimum number should not be less than half of the number of the peaks 101 or troughs 103 of each first circumferential connector 21.

[0101] The number of the second knots 2112 on a first circumferential connector 21 is not limited, that is, there may be no self-wound knots between adjacent peaks 101 or troughs 103, or there may be multiple knots. The number of the second knots 2112 should match the required shape of the axial connector 22.

[0102] The axial connecting body 22 is interwoven around the wave crest 101, the first knot 2111, the second knot 2112, the wave trough 103 and the first knot 2111. The axial connecting body 22 is formed by bending, winding and heat treatment shaping of a metal wire, and its circumferential shape is the same as that of the single-ring bracket 10, which is a circular or approximately circular loop. When the axial connecting body 22 is wound around the wave crest 101 or the wave trough 103, it needs to pass through the gap of the first knot 2111 to ensure that the axial connecting body 22 binds itself, the first knot 2111 and the wave crest 101 or the wave trough 103 together, so as to limit the sliding of the winding point of the first knot 2111 and the axial connecting body 22 on the single-ring bracket 10. The axial connecting body 22 needs to be wound through the gap of the second knot 2112 to limit the sliding of the axial connecting body 22 on the first circumferential connecting body 211.

[0103] It should be noted that in the present invention, the axial connecting bodies 22 are evenly arranged in the circumferential direction, that is, the density of the axial connecting bodies 22 in the circumferential direction is the same.

[0104] It should be noted that in the present invention, at the first knot 2111 or the second knot 2112 of the axial connecting body 22, in addition to using Figure 9 the directly winding method shown, it can also be tied into knot forms such as Prusik knot, single knot, figure-eight knot, double fisherman's knot, etc. For example: when the first knot 2111 is a Prusik knot, the axial connecting body 22 can tie a reverse Prusik knot here to form an interpenetrating double Prusik knot. When the second knot 2112 is a single knot, the axial connecting body 22 can tie a single knot here to form a double knot.

[0105] It should be noted that in the present invention, the number and uniformity of the winding points of the axial connecting body 22 on the wave crest 101, the wave trough 103 or the circumferential connecting body 21 are not fixed, that is, winding may not be performed on some wave crests 101, wave troughs 103 or a certain section of the circumferential connecting body 21.

[0106] As shown in Figure 9 the figure, the connecting body 20 includes two axial connecting bodies 22a and 22b. One axial connecting body 22b is an "N" shape with staggered heights, and the other axial connecting body 22a is a reverse "N" shape with staggered heights.

[0107] Figure 9 It shows a situation where the first knot 2111 is a Prusik knot and the second knot 2112 is a single knot for example. The first knot 2111 is provided on each wave crest 101 or wave trough 103, and a second knot 2112 is provided between each adjacent wave crest 101 or wave trough 103. The axial connecting body 22 is wound once on each first knot 2111 and second knot 2112.

[0108] As Figure 9As shown, in the present invention, the second circumferential connector 212 is located between two adjacent first circumferential connectors 211 and can be circumferentially connected to the axial connector 22 in a winding manner. In Figure 9 , the connector 20 includes three circumferential connectors 21, namely two first circumferential connectors 211 and one second circumferential connector 212. One first circumferential connector 211 is wound around the peak 101 of the single-loop stent 10 on one side, and the other first circumferential connector 211 is wound around the valley 103 of the single-loop stent 10 on the other side; one second circumferential connector 212 is located on the intermediate plane of the axial connector 22 in the axial direction, and it is wound around the axial connector 22. Optionally, it can also be tied to the axial connector 22 in a suitable knotting manner.

[0109] It should be noted that in the present invention, the number and shape of the axial connectors 22 between two adjacent single-loop stents 10 are not limited to Figure 9 the situation shown. The number and shape of the axial connectors 22 should match the required support performance and compliance performance of the vascular stent 100. As an example, the number of circumferential connectors 21 between two adjacent single-loop stents 10 is 2-5, that is, in addition to one first circumferential connector 211 wound around the opposite peaks 101 and valleys 103 of the two adjacent single-loop stents 10 on both sides, there are also 0-3 second circumferential connectors 212 distributed in the axial direction of the axial connector 22. That is to say, in some embodiments, the connector may not be provided with a second circumferential connector 212. The number of axial connectors 22 between two adjacent single-loop stents 10 can be 1-3, and the shape is "N" type, reverse "N" type, or "Z" type.

[0110] As Figure 9 shown, the connector 20 is in a grid shape composed of several triangles with different orientations. It can be understood that according to the above-mentioned setting method of the circumferential connector 21 and the axial connector 22, the final grid shape of the connector 20 can also be Figures 10a - 10e the various grid shapes shown. The grid shape of the same connector 20 can be single or different in segments. The grid shapes of several connectors 20 on the same vascular stent 100 can be the same or different.

[0111] Due to the structural design of the connector 20 of the present invention, the circumferential connector 21 and the axial connector 22 limit each other to prevent the knot from sliding on the wave rod of the stent.

[0112] The connecting body of the existing bare stent can only use the vertex of the stent ring of the single-ring stent as the winding point of the knot; while in the structural design of the connecting body 20 of the present invention, the circumferential connecting body 21 can be used as the winding point of the axial connecting body at any position within 360° in the circumferential direction. The axial connecting body 22 has more knot winding points, which enables the axial connecting body 22 to have a diversified structural design, thereby increasing the axial support force and better preventing the blood vessel stent 100 from shortening.

[0113] In the structural design of the connecting body 20 of the present invention, while having a certain axial support force, the axial length of the connecting body 20 can be increased. Thus, when the stent is bent, it can prevent cross-section distortion caused by the too small axial length of the connecting body 20, improving the bending performance of the existing bare stent.

[0114] As Figure 1 shown, in the present invention, the film 30 is one of the components of the blood vessel stent 100, and the blood vessel stent 100 may include several films 30. The film 30 is a layer of flexible film material attached to the single-ring stent 10 or the connecting body 20. The material of the film 30 may be, for example, PET (polyester fiber, terylene) or EPTFE (polytetrafluoroethylene) and other materials. The film 30 is attached to at least one single-ring stent 10 or one connecting body 20, and at most to all the single-ring stents 10 and connecting bodies 20.

[0115] As Figure 11 shown, the setting position of the film 30 is selectable and can be attached to different single-ring stents 10 or connecting bodies 20 of the blood vessel stent 100 as required. The film 30 can be attached to the outside, inside or both inside and outside of the single-ring stent 10 or the connecting body 20. The film 30 can be attached to the single-ring stent 10 or the connecting body 20 by any suitable method such as adhesion (such as heat melting) or sewing.

[0116] Next, the beneficial effects of the blood vessel stent 100 of the present invention will be described by comparing it with the existing stents.

[0117] 1. The two ends of the blood vessel stent 100 of the present invention can be attached with the film 30, which can relieve the compression of the free vertex at the end of the stent on the blood vessel inner wall and reduce the risk of intimal rupture.

[0118] Figures 12a - 12c The comparison schematic diagrams of the traditional covered stent, the traditional bare stent and the blood vessel stent of the present invention are respectively shown. Among them, Figure 12a is a traditional covered stent, and one end (the right end in the figure) is designed with a bare area without the film. There is a free vertex FV in this area. When this traditional covered stent is intervened, the free vertex FV will continuously and intermittently compress the blood vessel inner wall with the pulsation of the blood vessel. The reason for the existence of the bare area in this traditional covered stent is as Figure 13As shown in the figure, when a traditional covered stent is compressed and loaded into the sheath 40, it requires an exposed area that can be grasped by the fixing claw head 50 provided at the end of the inner catheter 60 to complete the fixation of the stent to the delivery device, and then the stent can be dragged and pulled.

[0119] Figure 12b As shown in the figure, a traditional bare stent is shown. There are free vertices FV at both ends of it. When this traditional bare stent is intervened, the free vertices FV will continuously and intermittently compress the inner wall of the blood vessel along with the pulsation of the blood vessel.

[0120] Figure 12c As shown in the figure, the blood vessel stent 100 of the present invention is shown. The film 30 can be attached to both ends of it, thereby eliminating the free stent ring vertices, using the film to relieve the compression of the vertices on the inner wall of the blood vessel, and reducing the risk of intimal rupture. As Figure 14 As shown in the figure, when the blood vessel stent 100 of the present invention is compressed and loaded into the sheath 40, the fixing claw head 50 provided at the end of the inner catheter 60 can grasp the exposed area of the blood vessel stent 100 where the film is not attached to complete the fixation of the blood vessel stent 100 to the delivery device, and then the blood vessel stent 100 can be dragged and pulled.

[0121] 2. The design structure of the connecting body 20 of the blood vessel stent 100 of the present invention can greatly reduce the implantation shortening rate of the blood vessel stent.

[0122] As Figure 15a As shown in the figure, for a traditional bare stent, since there is no circumferential connecting body, the axial connecting body 20' can only use the trough or peak of the single-ring stent 10' as the connecting and winding point. After the stent is axially stressed, the connecting body 20' is extremely easy to reverse axially, causing the stent to axially shorten, and the larger the axial dimension of the connecting body, the greater the shortening rate. As Figure 7 As shown in the figure, in the present invention, the axial connecting body 22 of the connecting body 20 can use the peak 101, trough 103 of the single-ring stent 10 or the own knot points (the first knot 2111 and / or the second knot 2112) of the circumferential connecting body 21 as the connecting and winding points. Thus, the axial connecting body 21 has more axial vertical segments or inclined segments in the circumferential direction, which makes the connecting body 20 have stronger axial support force and can further resist the axial shortening of the blood vessel stent 100.

[0123] As Figure 15b As shown in the figure, for the existing bare stent, due to the lack of the limitation of the circumferential connecting body, the knot of the axial connecting body 20' of the stent is extremely easy to slide under the axial force at the trough or peak of the single-ring stent 10', and at the same time, the axial length of the overall stent becomes shorter. While in the present invention, as Figure 7As shown in the figure, the connector 20 of the present invention limits each other through the circumferential connector 21 and the axial connector 22, so that the knot is completely limited at the peak or trough of the single-ring stent 10, and it is not easy to slide under the axial force, reducing the axial shortening rate of the overall stent. 3. The design structure of the connector 20 of the vascular stent 100 of the present invention can provide a certain radial supporting force.

[0124] 3. The design structure of the connector of the vascular stent 100 of the present invention can provide a certain radial supporting force.

[0125] As Figure 15a shown, the existing bare stent has no circumferential connector, and the radial supporting force of the overall stent is almost completely provided by each single-ring stent 10', and the connector 20' has almost no supporting force in the radial direction. As Figure 7 shown, the connector 20 of the present invention has several circumferential connectors 21, which can provide partial supporting force in the radial direction, while ensuring the anchoring performance of the overall stent, ensuring the stability of the stent.

[0126] At the same time, due to the lack of radial supporting force of the connector of the existing bare stent, this leads to uneven distribution of the radial supporting force of the overall stent. Therefore, the single-ring stent 10' must have sufficient radial supporting force to stably anchor the overall stent in the blood vessel without sliding, which will cause the pressure generated by the single-ring stent 10' on the inner wall of the blood vessel to be much greater than that of the connector 20' part. The inner wall of the patient's blood vessel is very weak, and the single-ring stent 10' with a large pressure is very likely to cause secondary damage to the inner wall of the blood vessel. However, the connector 20 of the vascular stent 100 of the present invention has a certain radial supporting force, so that the radial supporting force of the single-ring stent can be appropriately weakened while ensuring that the radial force of the overall vascular stent 100 remains unchanged.

[0127] 4. The design structure of the connector 20 of the vascular stent 100 of the present invention can provide a certain axial supporting force.

[0128] As Figure 15c shown, the connector 20' of some existing bare stents lacks a support member in the axial direction, and the circumferential centers of each single-ring stent 10' originally on the axial center line are prone to deflection, and the overall stent will then be eccentric and collapse. As Figure 7 shown, in the present invention, the axial connector 22 of the vascular stent 100 can have several axial vertical rods, which can be used as axial support members to increase the axial supporting force of the connector and stabilize each single-ring stent 10.

[0129] 5. After the vascular stent 100 of the present invention generates a large bend, the cross-section of the arch part of the stent has a small distortion, and the reduction amount of the cross-sectional area of the arch part of the stent is small, and a good circular arch cross-section can be maintained.

[0130] Figure 16a and16b Respectively shown are the comparative schematic diagrams of an existing partial stent and the vascular stent of the present invention in a large bending configuration. As Figure 16a shown, the axial dimension of the connecting body of the existing stent is small or the connecting body has no axial height. When the overall stent undergoes a large bend, the cross-section of the stent arch is distorted, the circular cross-section shrinks into an ellipse, and the minor axis a of the ellipse is much smaller than the major axis D1 (i.e., the diameter D1 of the single-ring stent).

[0131] As Figure 16b shown, the connecting body 20 of the vascular stent 100 of the present invention has a large axial dimension, and the axial support force of the connecting body 20 is large. When the overall vascular stent 100 undergoes a large bend, the connecting body 20 is not easily deformed, and the cross-section distortion of the stent arch is small. Although the circular cross-section also shrinks into an ellipse, the minor axis b of the ellipse is slightly smaller than D1 (i.e., the diameter D1 of the single-ring stent). Therefore, after the vascular stent 100 of the present invention generates a large bend, the impact on the blood flow rate is small, the inner diameter shape of the bend is good, and it can better fit the inner wall of the blood vessel with a large bend.

[0132] In addition, if the axial dimension of the connecting body of the existing stent shown in Figure 16a is increased, although the problem of cross-section distortion can be significantly improved, it will simultaneously bring the problem of an increased axial shortening rate as shown in Figure 15a shown.

[0133] 6. As Figure 17 shown, the local film covering of the vascular stent of the present invention and the excellent bending performance of the stent are combined, enabling the vascular stent 100 of the present invention to be used for interventional treatment of Debakey type II without the need for branch vessel reconstruction and without the dissection involving the aortic arch.

[0134] At the present stage, there are few vascular stents specifically used for treating Debakey type II, especially for Debakey type II without the need for branch vessel 704 reconstruction and without the dissection 705 involving the aortic arch 702. Since the ascending aorta 701 is short and close to the heart, to prevent the vascular stent inserted into this part from falling off, the stent needs to have a certain length sufficient to cross the aortic arch 702 for anchoring. If a traditional covered stent is used for interventional treatment, the polymer film will block the blood supply of the branch vessel 704 at the aortic arch 702, so holes need to be opened in the film and precise adaptation between the holes and the branch vessel 704 needs to be completed, which greatly increases the difficulty of the surgical operation.

[0135] When the vascular stent 100 of the present invention is used for the interventional treatment of Debakey type II without the need for branch vessel reconstruction and the dissection does not involve the aortic arch, a film 30 is attached to the proximal end of the vascular stent 100. This section can seal the break of the dissection 705 on the ascending aorta 701, achieving the purpose of treating Debakey type II dissection. The non-film section 100a of the vascular stent 100 of the present invention that spans the aortic arch 702 can not only allow blood to freely flow from the thoracic aortic vessel to the branch vessel 704, but also prevent the break of the dissection 705 from expanding towards the aortic arch 702. At the same time, the film 30 attached to the distal end of the vascular stent 100 can relieve the compression of the apex of the free end of the stent on the vascular inner wall and reduce the risk of intimal rupture.

[0136] 7. As Figure 18 shown, the vascular stent 100 of the present invention can be used as a restrictive bare stent to limit the excessive opening of the distal end of the covered stent and prevent the occurrence of SINE.

[0137] As Figure 18 shown, when using a traditional covered stent to treat Debakey type III dissection, the vascular stent 100 of the present invention with a slightly smaller specification than the covered stent is pre-placed at the distal end of the descending aorta 703 and a part of the abdominal aorta 706 as a restrictive bare stent. It can not only limit the excessive opening of the distal end of the covered stent (not shown) and prevent the occurrence of SINE, but also the exposed stent part of the vascular stent 100 of the present invention will not interfere with the blood flow of multiple branch vessels 704 in the abdominal aorta 706.

[0138] At the same time, while the proximal end of the restrictive bare stent restricts the excessive swelling of the distal end of the covered stent, the distal end of the covered stent also has a certain outward expansion reaction force on the proximal end of the restrictive bare stent. If a traditional bare stent is used, the reaction force will increase the compression of the free apex on the vascular inner wall. When using the vascular stent 100 of the present invention as a restrictive bare stent, since the film 30 is attached to the proximal end of the vascular stent 100, this greatly relieves the compression of the apex on the vascular inner wall and reduces the risk of intimal rupture.

[0139] 8. The vascular stent 100 of the present invention can effectively alleviate the problems of eccentricity and collapse of some existing bare stents.

[0140] Figure 19a And 19b respectively show schematic diagrams of eccentricity and collapse of the existing restrictive bare stent 100' after intervention. Among them, Figure 19a shows the eccentricity and collapse of the distal end of the restrictive bare stent 100', Figure 19b shows the eccentricity and collapse of the proximal end of the restrictive bare stent 100'.

[0141] Existing bare stents lack radial support force and columnar support members axially, so some existing bare stents are prone to eccentricity and collapse at the curved parts of blood vessels. At the same time, the thrust and tension generated during the loading and releasing of the stent may cause the connection nodes to slide on the stent rods, which may also lead to distortion of the stent morphology.

[0142] As Figure 15a shown, due to the lack of circumferential connection body limitation in the existing bare stent, the knots of the axial connection body 20' are extremely prone to sliding under axial force at the trough or peak of the single-ring stent 10'. When the sliding amount of the node is large, the morphology of the stent will produce irreversible distortion, resulting in eccentricity and collapse. As Figure 7 shown, the connection body 20 of the present invention limits each other through the circumferential connection body 21 and the axial connection body 22, so that the knot is completely limited at the peak or trough and is not prone to sliding under axial force, increasing the stability of the stent.

[0143] 9. The manufacturing technology of the vascular stent 100 of the present invention can relatively easily change the overall mechanical properties of the stent and produce more stents with different mechanical property specifications.

[0144] According to the structural design method of the vascular stent 100 of the present invention, by appropriately adjusting the structure of its connection body 20, overall stents with different support performances and compliance performances can be obtained. For example: appropriately increasing the number of circumferential connection bodies 21 can appropriately increase the support performance of the overall vascular stent 100; appropriately modifying the grid morphology of the connection body 20 can relatively easily change the compliance performance and support performance of the overall vascular stent 100.

[0145] In the description herein, numerous specific details are provided, such as examples of components and / or methods, to provide a complete understanding of embodiments of the present invention. However, those skilled in the art will recognize that embodiments of the present invention may be practiced without one or more of the specific details or by other devices, systems, components, methods, parts, materials, articles, etc. In other instances, well-known structures, materials, or operations are not specifically shown or described in detail to avoid obscuring aspects of embodiments of the present invention.

[0146] It should also be understood that one or more of the elements shown in the drawings may also be implemented in a more separated or more integrated manner, or even removed because they cannot be operated in some cases or provided because they may be useful for a particular application.

[0147] In addition, unless otherwise expressly specified, any reference signs in the drawings shall be construed as merely exemplary and not as limiting. Further, unless otherwise indicated, the term "or" as used herein is generally intended to mean "and / or". Where terms are anticipated to be unclear because of the separative or combinative capabilities provided, the combination of components or steps will also be regarded as being specified.

[0148] The foregoing description of the embodiments of the invention (including the content in the abstract) is not intended to be exhaustive or to limit the invention to the precise forms disclosed herein. Although specific embodiments of the invention and examples of the invention have been described herein for illustrative purposes only, various equivalent modifications will be within the spirit and scope of the invention as will be recognized and understood by those skilled in the art. As noted, these modifications of the invention may be made in accordance with the foregoing description of the embodiments of the invention and these modifications will be within the spirit and scope of the invention.

[0149] The systems and methods have been described generally herein to assist in understanding the details of the invention. In addition, various specific details have been given to provide a general understanding of embodiments of the invention. However, those skilled in the relevant art will recognize that embodiments of the invention may be practiced without one or more of the specific details, or with other devices, systems, accessories, methods, components, materials, parts, etc. In other instances, well-known structures, materials, and / or operations have not been shown or described in detail to avoid obscuring aspects of the embodiments of the invention.

[0150] Accordingly, while the invention has been described herein with reference to its specific embodiments, modifications, various changes and substitutions are also within the foregoing disclosure, and it should be understood that in some instances, some features of the invention will be employed without corresponding use of other features without departing from the scope and spirit of the claimed invention. Accordingly, many modifications may be made to adapt a particular environment or material to the essential scope and spirit of the invention. The invention is not intended to be limited to the specific terms and / or specific embodiments disclosed as the best mode contemplated for carrying out the invention, but the invention will include any and all embodiments and equivalents falling within the scope of the appended claims. Accordingly, the scope of the invention will be determined only by the appended claims.

Claims

1. A vascular stent, characterized in that, it includes: A number of single - loop stents, arranged at intervals along the axis. While the single - loop stents extend circumferentially, they undulate axially in a wavy shape; A number of connectors, connecting adjacent two single - loop stents through the connectors; Among them, the connector includes two annular first circumferential connectors and at least one axial connector; one of the first circumferential connectors successively winds around the wave crests of one of the adjacent two single - loop stents in the circumferential direction, and the other first circumferential connector successively winds around the wave troughs of the other of the adjacent two single - loop stents in the circumferential direction. The first circumferential connector includes a first knot formed by winding around the wave crest or the wave trough and a second knot formed by its own winding and located between adjacent wave crests or wave troughs; The axial connector is located between adjacent two first circumferential connectors. While the axial connector extends circumferentially, it interweaves and winds around the wave crest, the first knot wound on it, the second knot, the wave trough, and the first knot wound on it to limit the sliding of the winding points of the first knot and the axial connector on the single - loop stent, and to limit the sliding of the axial connector on the first circumferential connector.

2. The vascular stent according to claim 1, characterized in that, the material of the single - loop stent is shape - memory alloy.

3. The vascular stent according to claim 1, characterized in that, the single - loop stent includes wave crests, wave troughs, and wave rods connecting the wave crests and the wave troughs, and the wave rods are tangent or non - tangent to the wave crests / wave troughs.

4. The vascular stent according to claim 1, characterized in that, the relative positions of the single - loop stents of the vascular stent are the same or different.

5. The vascular stent according to claim 1, characterized in that, the material of the number of connectors is shape - memory alloy.

6. The vascular stent according to claim 1, characterized in that, the number of connectors is in a mesh form.

7. The vascular stent according to claim 1, characterized in that, the axial connector is completely distributed in the circumferential direction.

8. The vascular stent according to claim 1, characterized in that, the vascular stent further includes a film, and the film is attached to the single - loop stent and / or the number of connectors.

9. The vascular stent according to claim 1, characterized in that, the number of the first knots of one of the first circumferential connectors is greater than or equal to half of the number of wave crests / wave troughs of one single - loop stent.

10. The vascular stent according to claim 1, characterized in that, the circumferential connector is a single - strand metal wire or a multi - strand twisted metal wire.

11. The vascular stent according to claim 1, characterized in that, the first circumferential connector is provided with a first knot on each wave crest / wave trough of the single - loop stent, and a second knot is provided between each adjacent wave crest / wave trough of the single - loop stent, and the axial connector winds around each first knot and the second knot once.

12. The vascular stent according to claim 1, characterized in that, The axial connectors include at least two. One of the axial connectors is in an "N" shape, and the other axial connector is in a reverse "N" shape.

13. The vascular stent according to claim 1, wherein, the axial connectors are evenly distributed along the circumferential direction of the vascular stent.

14. The vascular stent according to claim 1, wherein, the cross-sectional dimension of the metal wire of the plurality of connectors is smaller than the cross-sectional dimension of the wire of the single-ring stent.

15. The vascular stent according to claim 14, wherein, the ratio of the cross-sectional dimension of the wire of the single-ring stent to the cross-sectional dimension of the metal wire of the plurality of connectors is between 2 and 20.

Images