Short-head-end stent conveying system and stent system comprising same
By setting extreme positions at the distal end of the stent delivery system and adopting a closed-loop or open-loop design, combined with specific materials and structures, the risk of puncturing the vessel wall during stent implantation in tortuous blood vessels has been resolved, achieving safer stent delivery and implantation.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- ACCUMEDICAL BEIJING LTD
- Filing Date
- 2024-12-31
- Publication Date
- 2026-04-10
AI Technical Summary
In tortuous blood vessels, during the implantation of self-expanding stents, the relative movement between the distal end of the stent and the distal end of the delivery system may cause puncture of the blood vessel wall, increasing the risk of injury. Existing technologies are unable to effectively reduce this risk.
Design a short-end stent delivery system, setting the far end of the stent delivery system at the extreme position, that is, on the proximal side at 0.8 to 1 times the nominal diameter of the far end of the stent to be delivered, and adopting a far-end closed-loop or open-loop structure, combined with stent delivery systems of different materials and structures, to ensure that the stent maintains shape stability and pushability during delivery.
It reduces the risk of damage to the vessel wall during stent delivery, release and implantation, and improves operational safety and the stent's guidance capability in complex vascular pathways.
Smart Images
Figure CN224099519U_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The present application belongs to the field of medical devices, and particularly relates to a short head-end stent delivery system and a stent system comprising the same. BACKGROUND
[0002] Self-expanding stents rely on their self-expanding properties, which are loaded into the delivery system after being radially compressed, and are loaded into the microcatheter together with the delivery system. By applying a pushing force to the proximal end of the delivery system or other operations, the self-expanding stent is delivered from the proximal end outside the body (such as the radial artery or femoral artery) to the lesion site (such as a vascular tumor), and is radially expanded in the lesion area to complete the implantation of the stent. However, in tortuous blood vessels, during the implantation process, as the microcatheter is withdrawn, the radial constraint of the distal end of the self-expanding stent gradually disappears, and the distal end of the self-expanding stent expands. At the same time, the expansion degree of the delivery system is much smaller than that of the self-expanding stent, and even in some cases, the distal end of the delivery system does not self-expand. In this case, the relative movement between the distal end of the stent and the distal end of the delivery system can cause the distal end of the delivery system to contact and pierce the blood vessel wall, increasing the risk of blood vessel damage.
[0003] Therefore, there is a need in the art to develop a stent delivery system with low risk of blood vessel puncture, especially suitable for the implantation of self-expanding stents in tortuous blood vessel lesion areas. SUMMARY
[0004] In view of the deficiencies of the prior art, one of the purposes of the present application is to provide a short head-end stent delivery system, the delivery direction of the stent to be delivered is axial, the stent delivery system has an axial extension length, the stent to be delivered is loaded at the distal end of the stent delivery system, and the proximal end of the stent delivery system is used to receive a pushing force and transmit it to the distal end of the stent delivery system.
[0005] The position extending a predetermined distance in the axial direction from the distal end of the stent to be delivered is defined as the limit position, and the distal end of the stent delivery system is located on the proximal side of the limit position.
[0006] The predetermined distance is 0.8-1 times the nominal diameter of the stent to be delivered.
[0007] The present application achieves better operability and safety by setting the stent delivery system on the proximal side of the limit position (i.e. 0.8-1 times the nominal diameter of the distal end of the stent to be delivered). This setting reduces the potential risk of damage to the blood vessel wall by the stent delivery system during stent delivery, release and implantation.
[0008] In the process of selecting a stent, the stent is usually selected according to the diameter of the blood vessel at the lesion site, and the nominal diameter of the stent is usually slightly larger than the diameter of the diseased blood vessel, so as to ensure that the stent can effectively guide blood flow or restore the patency of the blood vessel after implantation. Human blood vessels branch out from the ventricle to increasingly finer blood vessels. Under this anatomical structure, the distal end of the stent delivery system is arranged at the limit position, which can not only provide sufficient pushing force and guiding effect to ensure accurate delivery of the stent to the target site, but also better utilize the space provided by the contralateral blood vessel at the bifurcation of the blood vessel in the bifurcated blood vessel lesion, thereby avoiding excessive pressure on the blood vessel wall.
[0009] Preferably, the distal end of the stent delivery system is located within the range of -5mm to + the nominal diameter of the stent to be delivered, with the distal end of the stent to be delivered as the 0 point.
[0010] The range of -5mm to + the nominal diameter of the stent to be delivered can better coordinate the pushing performance, guiding effect and safety of the stent delivery.
[0011] Preferably, the distal end of the stent delivery system is located proximal to the distal end of the stent to be delivered, with the distal end of the stent to be delivered as the 0 point, and the stent to be delivered is a stent with a closed loop at the distal end.
[0012] When the distal end of the stent delivery system is located proximal to the distal end of the stent to be delivered, the distal end of the stent is not supported by the delivery system during delivery, which can cause problems such as insufficient pushing performance and reduced guiding effect. To overcome this defect, the stent to be delivered is designed as a closed loop structure at the distal end, which can effectively improve the pushing performance and ensure better shape stability. Specifically, the closed loop design at the distal end of the stent can maintain excellent pushing performance during delivery, and can maintain shape stability without the load of the delivery system, thereby improving the guiding ability and ensuring smooth implantation of the stent in complex blood vessel paths.
[0013] The closed loop at the distal end means that the distal end of the stent is designed as a closed loop structure, i.e. the wire or other material at the distal end of the stent forms a closed loop structure in the axial direction through a specific design.
[0014] Preferably, the stent to be delivered is a cobalt-chromium alloy stent.
[0015] Preferably, the stent delivery system comprises any one or a combination of at least two of a guide wire, a wire braided structure, and a carved hollow structure.
[0016] The combination of at least two typically but not limitedly includes a combination of a proximal guide wire and a distal wire braided structure, a combination of a proximal guide wire and a distal carved hollow structure, etc.
[0017] The wire braiding structure and the engraved hollow structure can be formed by a heat setting process to have a shape of "large middle internal space and tight both ends".
[0018] The wire braiding structure is generally formed by crossing and braiding metal wires into a tube net structure, and then heat setting into a structure of large middle internal space and tight both ends. The crossing and braiding of the metal wires into a tube net structure can include any one of an over-under braiding method, a two-over-two braiding method, a double-strand composite braiding method, and a triple-strand composite braiding method.
[0019] The engraved hollow structure is formed by engraving a metal tube into a hollow structure, binding both ends, and then heat setting into a structure of large middle internal space and tight both ends. The engraving method can include laser engraving. The hollow pattern of the engraved hollow structure is not limited in the present application, and any hollow pattern that can be heat set into a structure of large middle internal space and tight both ends can be used in the present application.
[0020] In a preferred technical solution, at least the distal end of the stent delivery system is a wire braiding structure, and the elastic modulus of the wire is ≤180 GPa, preferably 30-80 GPa.
[0021] In another preferred technical solution, at least the distal end of the stent delivery system is an engraved hollow structure, and the elastic modulus of the strut constituting the hollow structure is ≤180 GPa, preferably 30-80 GPa.
[0022] In another preferred technical solution, the stent delivery system is a guide wire, and the elastic modulus of the distal end of the guide wire is ≤180 GPa.
[0023] In short, the present application does not limit the selection of the stent delivery system, and any known or new stent delivery system can be used in the present application, but it is preferred to select a structure composed of a basic structure (such as a wire or a strut) with an elastic modulus of 180 GPa or less as the distal end of the stent delivery system, which can better reduce the irritation and damage to the blood vessel wall.
[0024] Preferably, the stent delivery system includes a proximal pushing part and a distal soft part, and the elastic modulus of the distal soft part is ≤180 GPa.
[0025] The soft part has a lower elastic modulus, which can effectively reduce the irritation and damage to the blood vessel wall when contacting the blood vessel wall. The soft part can be composed of a wire braiding structure and / or an engraved hollow structure.
[0026] Preferably, the elastic modulus of the material of the distal end of the stent delivery system is less than the elastic modulus of the material of the proximal end of the stent delivery system. The materials of the distal end and the proximal end of the stent delivery system are selected to have different elastic modulus, so that the stent delivery system can improve the pushability of the stent delivery system while ensuring low irritation and low damage of the distal end to the blood vessel wall.
[0027] Preferably, the distal end of the stent delivery system comprises a radiopaque material structure for visualizing the distal end of the stent delivery system.
[0028] Preferably, the guide wire comprises a proximal end push part and a distal end soft part, the distal end soft part is made of a radiopaque material, or the distal end of the soft part is wound with a radiopaque coil.
[0029] The second object of the present application is to provide a stent system comprising:
[0030] The stent delivery system of the first object;
[0031] The stent to be delivered is loaded at the distal end or near the distal end of the stent delivery system of the first object.
[0032] The stent system provided in the second object of the present application has good pushability and low probability of blood vessel damage.
[0033] Preferably, the distal end of the stent to be delivered is an open loop structure, the distal end of the stent to be delivered is point 0, and the distal end of the stent delivery system is located within the range of 0 to + the nominal diameter of the stent to be delivered.
[0034] When the distal end of the stent to be delivered is an open loop structure, the radial pushability of the stent itself is relatively low, therefore, the length of the stent delivery system is set on the side of the distal end of the stent to be delivered, and the length is less than the nominal diameter of the stent to be delivered, so as to improve the pushability of the stent delivery system while ensuring sufficient safety.
[0035] Preferably, the distal end of the stent to be delivered is a closed loop structure, the distal end of the stent to be delivered is point 0, and the distal end of the stent delivery system is located within the range of -5 mm to + the nominal diameter of the stent to be delivered.
[0036] When the distal end of the stent to be delivered is a closed loop structure, the stent itself has good axial pushability, therefore, the length of the stent delivery system can be selected in a wider range. The distal end of the stent delivery system can be set on the proximal side of the distal end of the stent to be delivered, such as within the range of -5 mm to 0, or within the range of + the nominal diameter of the stent to be delivered to 0, which can ensure the pushability and meet the needs of different application scenarios.
[0037] Preferably, the stent to be delivered is a cobalt-chromium alloy stent.
[0038] Compared with the prior art, the present application has the following beneficial effects:
[0039] The short head end stent delivery system provided by the present application sets the stent delivery system on the proximal side of the extreme position (0.8-1 times the nominal diameter of the distal side of the stent to be delivered), which can better reduce the risk of damage to the blood vessel wall during the delivery, release and implantation of the stent delivery system. BRIEF DESCRIPTION OF DRAWINGS
[0040] Figure 1 The structure schematic diagram of the stent system provided for example 1 is shown in the figure;
[0041] Figure 2 The structure schematic diagram of the distal end closed loop stent is shown in the figure;
[0042] Figure 3 The structure schematic diagram of the stent system provided for example 2 is shown in the figure;
[0043] Figure 4 The structure schematic diagram of the distal end open loop stent is shown in the figure;
[0044] Figure 5 The structure schematic diagram of the stent system provided for example 3 is shown in the figure.
[0045] Figure 6 The structure schematic diagram of the stent system provided for example 4 is shown in the figure. DETAILED DESCRIPTION
[0046] The technical scheme of the present application will be further explained and described in the following combined with the specific embodiments. It should be explained that the specific embodiments described herein are only used to explain and describe the technical scheme of the present application, and should not be understood as a limitation on the protection scope of the present application.
[0047] The present application will be further described in detail in the following combined with the drawings and embodiments. It can be understood that the specific embodiments described herein are only used to explain the related utility model, and not to limit the utility model. In addition, it should be explained that only the parts related to the utility model are shown in the drawings for convenience of description.
[0048] In the description of the present application, it should be understood that the terms "distal end" and "proximal end" herein should be understood as observed from the direction of the surgical operator, the "distal end" is the end far away from the surgical operator, and the "proximal end" is the end close to the surgical operator. The term "axial direction" herein should be understood as the stent pushing direction, the length direction of the guide wire or the length direction of the stent, and the term "radial direction" should be understood as the perpendicular direction of the "axial direction".
[0049] In the description of the present application, it should be noted that the embodiments and the features in the embodiments in the present application can be combined with each other without conflict.
[0050] Embodiment 1
[0051] As shown in the structural schematic diagram of the stent system provided for Embodiment 1, Figure 1 ( Figure 1 As shown in the structural schematic diagram of the stent system provided for Embodiment 1, Figure 2 As shown in the structural schematic diagram of the stent system provided for Embodiment 1,
[0052] The stent delivery system comprises a proximal pushing guide wire 110 and a distal pushing guide wire 120, and the distal pushing guide wire 120 is arranged at the distal end of the proximal pushing guide wire 110.
[0053] The stent to be delivered 200 is crimped at the distal end of the stent delivery system, and in the delivery state, the distal end of the distal pushing guide wire 120 is arranged at the proximal side-5mm of the distal end of the stent to be delivered 200; the stent to be delivered 200 is a distal end closed loop stent. The elastic modulus of the distal pushing guide wire 120 is 165GPa.
[0054] Preferably, the stent to be delivered 200 is a cobalt-chromium alloy stent.
[0055] Embodiment 2
[0056] As shown in the structural schematic diagram of the stent system provided for Embodiment 1, Figure 3 ( Figure 3 As shown in the structural schematic diagram of the stent system provided for Embodiment 1, Figure 4 As shown in the structural schematic diagram of the stent system provided for Embodiment 1,
[0057] The stent delivery system comprises a proximal pushing guide wire 110 and a distal soft part 130, and the distal soft part comprises a wire braided structure 131 connected to the distal end of the proximal pushing guide wire 110 and a radiopaque spiral coil 132 arranged at the distal end of the wire braided structure 131; the wire braided structure 131 is braided into a pipe network structure by crossing the metal wires, the two ends are bound, and then it is heat set into a structure with a large internal space in the middle and tight ends; the elastic modulus of the wire of the wire braided structure 131 is 60GPa (any wire in the range of 50-70GPa can be selected in other embodiments); the elastic modulus of the radiopaque spiral coil 132 is 165GPa.
[0058] The stent to be delivered 200 (with a nominal diameter of 2.3mm) is crimped on the distal soft part 130, and in the delivery state, the distal end of the distal soft part 130 is arranged at the distal end of the distal end of the stent to be delivered 200; the stent to be delivered 200 is a distal end open loop stent.
[0059] Preferably, the stent to be delivered 200 is a cobalt-chromium alloy stent.
[0060] In embodiment 2, the metal wire cross-woven tube net structure exemplarily can include any one of the following weaving methods: one over one, two over two, double-strand composite weaving, and three-strand composite weaving.
[0061] In other embodiments, the stent delivery system includes a proximal push wire 110 and a plurality of sequentially connected distal wire woven structures 130.
[0062] In other embodiments, the distal soft part 130 can also omit the distal radiopaque spiral coil 132.
[0063] Embodiment 3
[0064] As shown in the structural schematic diagram of the stent system provided for embodiment 3, a stent system includes: Figure 5 Figure 5 As shown in the structural schematic diagram of the stent system provided for embodiment 3, a stent system includes:
[0065] The stent delivery system includes a proximal push wire 110 and a distal engraved hollow structure 140, which is arranged at the distal end of the proximal push wire 110; the distal engraved hollow structure 140 is laser-engraved into a hollow structure by a metal tube, both ends are bound, and then heat set into a structure with a large internal space in the middle and tight ends; the elastic modulus of the distal engraved hollow structure 140 is 63 GPa (in other embodiments, any wire in the range of 50-70 GPa can be selected);
[0066] The stent to be delivered 200 (with a nominal diameter of 3.5 mm) is pressed and held on the distal wire woven structure 130, and in the delivery state, the distal end of the distal wire woven structure 130 is arranged at the distal end of the distal end of the stent to be delivered 200 by 3.0 mm; the stent to be delivered 200 is a distal open-loop stent.
[0067] Preferably, the stent to be delivered 200 is a cobalt-chromium alloy stent.
[0068] Embodiment 4
[0069] As shown in the structural schematic diagram of the stent system provided for embodiment 4, a stent system includes: Figure 6 Figure 6 As shown in the structural schematic diagram of the stent system provided for embodiment 4, a stent system includes:
[0070] The stent delivery system includes a proximal push wire 110 and a distal push wire 120, which is arranged at the distal end of the proximal push wire 110;
[0071] The stent to be delivered 200 (with a nominal diameter of 3.5 mm) is pressed in the distal end of the stent delivery system, and in the delivery state, the distal end of the distal pushing guide wire 120 is arranged at a position 3.2 mm distal to the distal end of the stent to be delivered 200; the stent to be delivered 200 is a distal end open loop stent. The elastic modulus of the distal pushing guide wire 120 is 130 GPa.
[0072] Preferably, the stent to be delivered 200 is a cobalt-chromium alloy stent.
[0073] Finally, it should be noted that: the above embodiments are only used to illustrate the technical solutions of the present application, and not to limit them; although the present application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that: it can still modify the technical solutions recorded in the foregoing embodiments, or make equivalent replacement for part or all of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present application.
Claims
1. A short tip stent delivery system, characterized by, The delivery direction of the stent to be delivered is axial, the stent delivery system has an axial length, the stent to be delivered is loaded at the distal end of the stent delivery system, and the proximal end of the stent delivery system is used to receive a pushing force and transmit it to the distal end of the stent delivery system; A position extending a predetermined distance in the axial direction from the distal end of the stent to be delivered is defined as a limit position, and the distal end of the stent delivery system is located on the proximal side of the limit position. The predetermined distance is 0.8-1 times the nominal diameter of the stent to be delivered.
2. The stent delivery system of claim 1, wherein, Taking the distal end of the stent to be delivered as the 0 point, the distal end of the stent delivery system is located within the range of -5 mm from the distal end of the stent to be delivered to the nominal diameter of the stent to be delivered.
3. The stent delivery system of claim 1 or 2, wherein, Taking the distal end of the stent to be delivered as the 0 point, the distal end of the stent delivery system is located on the proximal side of the distal end of the stent to be delivered, and the stent to be delivered is a distal end closed loop stent; the stent to be delivered is a cobalt-chromium alloy stent.
4. The stent delivery system of claim 1, wherein the stent delivery system is configured to deliver the stent to a target site in a patient's body. The stent delivery system includes any one or a combination of at least two of a guide wire, a wire braided structure, and a carved hollow structure.
5. The stent delivery system of claim 1, wherein the stent delivery system is configured to deliver the stent to a target site in a patient's body. At least the distal end of the stent delivery system is a wire braided structure, and the elastic modulus of the wire is ≤180 GPa.
6. The stent delivery system of claim 5, wherein the stent is a self-expanding stent. The elastic modulus of the wire is 30-80 GPa.
7. The stent delivery system of claim 1, wherein the stent delivery system is configured to deliver the stent to a target site in a patient's body. At least the distal end of the stent delivery system is a carved hollow structure, and the elastic modulus of the strut constituting the hollow structure is ≤180 GPa.
8. The support conveying system as described in claim 7, characterized in that, The elastic modulus of the strut constituting the hollow structure is 30-80 GPa.
9. The stent delivery system of claim 1, wherein, The stent delivery system is a guide wire, and the elastic modulus of the distal end of the guide wire is ≤180 GPa.
10. The stent delivery system of claim 1, wherein, The stent delivery system includes a proximal pushing part and a distal soft part, and the elastic modulus of the distal soft part is ≤180 GPa.
11. The stent delivery system of claim 1, wherein, The elastic modulus of the material at the distal end of the stent delivery system is less than the elastic modulus of the material at the proximal end of the stent delivery system.
12. The stent delivery system of claim 1, wherein, The distal end of the stent delivery system includes a radiopaque material structure.
13. The stent delivery system of claims 4 or 9, wherein, The guide wire includes a proximal pushing part and a distal soft part, the distal soft part is a radiopaque material, or the distal end of the soft part is wrapped with a radiopaque coil.
14. A stent system characterized by, The stent system includes: The stent delivery system of any one of claims 1-13; The stent to be delivered is loaded at the distal end or near the distal end of the stent delivery system of any one of claims 1-13.
15. The support system of claim 14, wherein, The distal end of the stent to be delivered is an open loop structure, the distal end of the stent to be delivered is 0 point, and the distal end of the stent delivery system is located within the range of 0-+5 mm from the distal end of the stent to be delivered.
16. The support system of claim 14, wherein, The distal end of the stent to be delivered is a closed loop structure, the distal end of the stent to be delivered is 0 point, and the distal end of the stent delivery system is located within the range of -5 mm to +5 mm from the distal end of the stent to be delivered.
17. The support system of claim 14, wherein, The stent to be delivered is a cobalt-chromium alloy stent.