Stent delivery device and stent system comprising same

Abstract

A stent delivery device and a stent system comprising same. The stent delivery device comprises a force-functional component which is arranged at a distal end and is configured to reduce a passive force exerted axially on the distal end of the stent delivery device, wherein the force-functional component is designed to have a structure that dissipates and / or redirects the passive force, and the distance between a distal end of the force-functional component and the distal end of the whole stent delivery device is smaller than or equal to the nominal diameter of a stent delivered by the stent delivery device. By means of providing the force-functional component, the stent delivery device effectively dissipates or redirects the reactive force generated when the distal end of the delivery device touches a vascular wall during a stent implantation process, thereby significantly reducing the force exerted by the stent delivery device on the vascular wall during the stent implantation process. The setting of the distance between the distal end of the force-functional component and the distal end of the whole stent delivery device ensures a safe landing of the distal end of the stent upon initial release, thereby further reducing the possibility of vascular injury during a stent deployment process.

Description

A support conveying device and a support system including the same. Technical Field

[0001] This invention belongs to the field of medical devices, specifically relating to a stent delivery device and a stent system including the stent. Background Technology

[0002] Self-expanding stents are tubular implants widely used in interventional vascular treatments. They are typically delivered from the proximal external site (such as the radial or femoral artery) via a delivery system to the lesion site and expand radially within the lesion area to complete implantation. Relying on their self-expanding properties, self-expanding stents can expand and remain fixed within the vascular lumen after the delivery system is withdrawn, thereby guiding blood flow or maintaining vascular patency.

[0003] However, there are certain operational risks involved in the implantation of self-expanding stents. Particularly during microcatheter retraction, the stent undergoes axial shortening while expanding radially. In this situation, the distal end of the delivery system may extend beyond the distal end of the self-expanding stent, increasing the risk of distal perforation of the vessel wall, a risk that is particularly pronounced in complex, tortuous vessels.

[0004] While self-expanding stents expand radially, they typically contract axially to some extent. This contraction effect can cause the distal end of the guidewire or pusher within the delivery system to shift forward, especially during continuous proximal push or catheter retraction. This thrust can be transmitted to the distal end, causing a sudden forward movement of the distal structure of the delivery device. When the distal structure extends beyond the stent itself and contacts the vessel wall, it can cause mechanical irritation to the vessel wall, potentially leading to vascular damage. This phenomenon is particularly pronounced in complex, tortuous vascular environments. Due to the curvature of the vascular structure, the transmission of the pushing force is not linear, and changes in vascular morphology can lead to distal mechanical instability, making it easier for the distal guidewire or delivery device to extend beyond the stent and contact the vessel wall.

[0005] When lesions occur at vascular bifurcation sites, the distal segment of the delivery system that can be anchored to a normal vascular segment is typically short. In such cases, proximal pushing force may cause the distal end of the delivery device to remain close to the vessel wall, or even directly abut against the vessel wall, thereby causing local vascular stress or potential damage. For such complex vascular anatomy, the rigidity of existing delivery systems may exacerbate this problem, making it difficult to stably control the distal structure and thus affecting the accuracy of stent deployment. Furthermore, fluctuations in the distal pushing force of the delivery system may also affect the stability of stent deployment. Small fluctuations in force during the pushing process may be amplified to the distal end, leading to unstable movement of the stent during deployment, affecting stent apposition and the final implantation outcome.

[0006] On the other hand, when lesions such as aneurysms are present at the bifurcation of a blood vessel, the length of the normal blood vessel used for anchoring the distal end of the stent is limited. In such cases, after the distal end of the stent lands, the distal end of the delivery system can easily extend beyond the stent and touch the vessel wall. Especially in cases of thin vessel walls or narrow lumens, contact by the distal end of the delivery system may cause puncture or damage to the vessel wall, further increasing the surgical risk. To reduce the risk of distal puncture of the vessel wall, although shortening the length of the delivery system seems to reduce this risk, this approach will result in insufficient pushing force of the delivery system, thereby affecting the delivery performance and maneuverability of the self-expanding stent. Insufficient pushing force may lead to inaccurate stent positioning or even failure to deploy correctly, thus affecting the implantation outcome.

[0007] Therefore, there is a need in the field to develop a stent delivery device that reduces the risk of distal vascular puncture during self-expanding stent delivery, minimizes vascular stress, and can reduce the risk of distal vascular puncture while ensuring sufficient delivery capability, especially suitable for tortuous vascular lesions to meet clinical application needs in complex vascular diseases. Summary of the Invention

[0008] To address the shortcomings of existing technologies, one objective of this invention is to provide a support conveying device, wherein the conveying direction of the support is axial, the axial center is defined as the axis direction, and the intersection of the axis direction with any cross section perpendicular to the axis direction is the axis center point of the cross section.

[0009] The support conveying device includes a force-functional component disposed at the distal end for reducing the passive force acting on the distal end of the support conveying device along the axial direction. The passive force is a reaction force generated when the distal end of the support conveying device abuts against an obstacle and transmitted from the distal end to the proximal end along the axial direction. The force-functional component is designed to have a structure that decomposes and / or redirects the passive force.

[0010] The distance between the distal end of the force-function component and the distal end of the support conveying device as a whole is less than or equal to the nominal diameter of the support conveyed by the support conveying device.

[0011] During stent delivery, the force-functional component provided in this application is subjected to radial restraint (typically due to the constraint of the microcatheter). In this state, the force transmission direction of the force-functional component is primarily along the axial direction, ensuring the stability and transmission of the pushing force. During stent implantation, as the microcatheter retracts, the restraint disappears, and the force-functional component deforms, enabling it to decompose or redirect the passive force. This reduces the risk of damage to the vessel wall caused by the passive force, particularly in cases where the distal end of the stent delivery device extends beyond the stent and contacts the vessel wall during implantation, thus lowering the risk of vessel wall puncture.

[0012] For diseases such as hemangiomas and endovascular stenosis, lesions may appear in different locations within the body's vascular system, including the proximal, mid, or distal segment of a vessel. When a lesion is located in the distal segment of a vessel, it is usually accompanied by a bifurcation structure, meaning the lesion is near or located in the bifurcation area. Those skilled in the art should understand that regardless of the lesion's location within the vessel, the final landing point of the stent is always set distal to the lesion. That is, the stent must cross the lesion and be withdrawn distally or pushed forward to achieve precise implantation in the lesion area. This process typically relies on the manipulation of the withdrawing catheter and / or the pushing of the stent to ensure accurate stent coverage of the lesion during deployment, improving treatment efficacy and avoiding complications caused by misalignment.

[0013] When a hemangioma is located at a vascular bifurcation, the distal end of the stent typically lands at the bifurcation, with the stent opening perpendicular to the vessel wall on the opposite side of the bifurcation. Due to the anatomical structure at the vascular bifurcation, the space that the distal end of the delivery device can extend after stent deployment is extremely limited. The stent's distal landing point is located downstream of the hemangioma, where the vessel diameter is typically slightly smaller than the diameter of the vessel at the hemangioma's location, approximately the nominal diameter of the stent to be implanted. Therefore, setting the distance between the distal end of the force-functional component and the distal end of the stent delivery device as less than or equal to the nominal diameter of the stent delivered by the device ensures that the distal end of the force-functional component will not penetrate the vessel wall on the opposite side of the bifurcation during the initial stent deployment. As the stent is gradually deployed and the constriction gradually dissipates, the force-functional component gains more buffer space, further reducing the contact force on the vessel wall and avoiding the risk of puncturing it. This design not only ensures safe landing of the stent's distal end during initial deployment but also further reduces the possibility of vascular injury during stent deployment, thereby improving the safety and accuracy of stent implantation.

[0014] In one specific embodiment, the support conveying device includes a force transmission network centered on an axis point at a distal end, used to decompose the force applied at the axis point along the force transmission network; the force functional component is the force transmission network;

[0015] The force transmission network converges at the far end near the axis point to form a far end center;

[0016] The force transmission direction of the force transmission network is closer to the axial direction and towards the proximal end when subjected to radial restraint;

[0017] When the force transmission network is not restrained by external force, it deforms, causing the force transmission direction of the force transmission network to deviate further from the axis direction and move towards the proximal side.

[0018] The stent delivery device provided in this application features a force transmission network at its distal end. This force transmission network converges near its axis to form a distal center, serving as the first point of contact for the delivery device. During stent implantation, when the distal end of the stent delivery device extends beyond the stent and contacts the vessel wall, the position of the distal center of the force transmission network is the first point of contact with the vessel wall. Therefore, the force transmission network is crucial for reducing the contact force between the distal end and the vessel wall during stent implantation, thereby lowering the risk of vessel wall puncture. During stent implantation, as the microcatheter is withdrawn, the constraint of the force transmission network disappears, and the force transmission network deforms. In this process, the force transmission network, through its deformation, converts the reaction force into a decomposed force deviating from the axis, and the deformation of the force transmission network offsets part or all of this decomposed force.

[0019] In short, in the specific embodiment described, the stent delivery device, through the setting of the force transmission network, can effectively reduce the force acting on the blood vessel wall during stent implantation, thereby reducing the risk of puncture due to excessive force on the blood vessel wall. This is of great clinical significance, especially in the application of complex blood vessels or bifurcation sites.

[0020] Preferably, the force transmission network includes at least one circular array of lines arranged near the axis center; the distal ends of the array lines of the circular array converge at the axis center.

[0021] That is, the array elements of the line arrangement structure are lines (including straight lines, spirals, curves, wavy lines, Z-shaped lines, etc.) with the axis center as the endpoint, which are defined as array lines, and the array direction is a circular array with the axis center as the center.

[0022] The force transmission network may include one arrangement structure, or two or more arrangement structures, preferably two or more arrangement structures. When the force transmission network includes two or more arrangement structures, the array lines of different arrangement structures may intersect each other.

[0023] The arrangement structure can be understood as merely a restriction on the far end of the force transmission network.

[0024] Preferably, when the force transmission network is not constrained by external force, the angle between the force transmission direction at the distal end and the axial direction is 0° to 80° (excluding 0°), for example, 2°, 5°, 8°, 12°, 18°, 25°, 33°, 40°, 45°, 56°, 60°, 63°, 67°, 70°, 74°, 77°, 79°, etc., preferably 1° to 30°.

[0025] By setting the aforementioned angle, the force transmission network has an initial state that deviates from the axis when there is no radial restraint. On the one hand, this makes it easier for the force transmission network to deform (angle greater than 0°, especially greater than 1°) after being subjected to axial force, thereby counteracting the force. On the other hand, it ensures that the force transmission network has a large axial contraction space (e.g., less than 80°, especially less than 30°), thereby reducing pressure and damage to the blood vessel wall.

[0026] Normally, the direction of force transmission in a force transmission network is the tangent at the far end of the force transmission line.

[0027] In an optional specific embodiment, the force transmission network is formed by connecting elastic pillars or by overlapping elastic threads.

[0028] Preferably, the material of the force transmission network is a superelastic material and / or a shape memory material, preferably a nickel-titanium alloy.

[0029] The force transmission network is made of an elastic material, preferably a hyperelastic material and / or a shape memory material, so that it can deform when subjected to radial restraint and when there is no external force restraint.

[0030] Preferably, the elastic support connection is formed by laser engraving, chemical etching or electrical discharge machining.

[0031] Preferably, the size of the elastic support is 0.03~0.1mm, such as 0.05mm, 0.06mm, 0.07mm, 0.08mm, 0.09mm, etc.

[0032] Preferably, the elastic threads are overlapped by weaving.

[0033] Preferably, the size of the elastic thread is 0.001~0.1mm, such as 0.005mm, 0.007mm, 0.01mm, 0.03mm, 0.05mm, 0.07mm, 0.09mm, etc.

[0034] This application does not impose specific limitations on the convergence method of the convergence end. Any known or new methods of convergence of array lines that can be obtained by those skilled in the art can be used in this application.

[0035] As an optional specific implementation, the force transmission network converges near the axis point to form a converging end. The converging end can be formed by any one or a combination of at least two of the following methods: convergence, welding, bonding, and integral molding.

[0036] Preferably, the convergence is achieved by converging the distal end of the force transmission network into a convergence component.

[0037] Preferably, the convergence component includes a rigid convergence component and / or a flexible convergence component, with a flexible convergence component being more preferred.

[0038] Preferably, the rigid converging component includes a rigid ring, and more preferably, the rigid ring is made of a radiopaque material.

[0039] Preferably, the flexible convergence component includes a flexible ring and a spiral winding structure, preferably a spiral coil.

[0040] In a preferred embodiment, the length of the converging end is less than or equal to the nominal diameter of the support conveyed by the support conveying device.

[0041] In the specific embodiment, a converging end is provided between the distal end of the force function component and the distal end of the stent delivery device as a whole. The length of the converging end is less than or equal to the nominal diameter of the stent delivered by the stent delivery device. This is used to prevent the distal end of the stent delivery device from penetrating the vessel wall on the opposite side of the vessel bifurcation in the initial stage of stent release, thereby improving the safety of stent implantation.

[0042] Preferably, the ratio of the length of the converging end to the length of the force transmission network under the bound state is 0:1 to 0.8:1, excluding 0:1, and preferably 0.1:1 to 0.6:1.

[0043] By setting the above ratio, the converging tip has a suitable length range relative to the force transmission network, thus balancing two needs: on the one hand, it allows the force transmission network sufficient length and space to effectively decompose the force on the converging tip, thereby reducing the risk of puncturing blood vessels; on the other hand, it improves the guidance of the converging tip, making the delivery device more stable in a restrained state, thereby improving the distal delivery and guidance performance of the stent delivery device; in addition, when the converging tip is made of radiopaque material, the appropriate length of the converging tip can also optimize the imaging effect.

[0044] In a preferred embodiment, the support delivery device of this application includes a force transmission network disposed at the distal end. The force transmission network is preferably woven from 4 to 64 elastic threads intersecting in a mesh pattern. The Shore A hardness (D) of the elastic threads is preferably 30 to 50. The elastic threads converge at the distal end to form a converging end, and the ratio of the length of the converging end to the length of the force transmission network in its constrained state is preferably 0.1:1 to 0.6:1. The force transmission network expands in the unconstrained state, and the angle between the force transmission direction of the force transmission network (i.e., the extension direction of the elastic threads at the distal end) and the axial direction is 1 to 30°. The shape of the force transmission network in the unconstrained state can be achieved through a pre-designed form.

[0045] In the preferred embodiment described in this application, the length ratio of the converging end, the number of metal wires in the force transmission network, the Shore hardness D value, and the angle between the force transmission direction and the axial direction work together to enable the entire stent delivery device to maintain good pushability, stability, and guidance during stent delivery, and to more effectively reduce the risk of damage to the blood vessel wall during stent deployment and implantation.

[0046] Specifically, a suitable convergence ratio (0.1:1 to 0.6:1) ensures that the distal end of the stent delivery device has a convergence tip of a certain length. During delivery, the convergence tip can converge the dispersed force of the force transmission network, resulting in better performance in terms of pushability, stability, and guidance of the stent delivery device. The appropriate hardness and number of the force transmission network wires, as well as the angle between the force transmission direction and the axial direction, allow for easier deformation during stent deployment and implantation, offsetting the force on the convergence tip and reducing damage to the blood vessel wall. At the same time, during stent delivery, the convergence of the convergence tip maintains good axial thrust inside the delivery catheter.

[0047] In an optional specific implementation, the distal end of the converging end has a convex curved surface, such as an arc surface or a spherical cap surface.

[0048] The converging end is designed with a convex curved surface to ensure that the distal end of the delivery device makes smoother and more uniform contact with the blood vessel wall, thereby reducing local pressure and irritation to the blood vessel wall, meeting the requirements for blood vessel wall protection, and effectively reducing the risk of the distal end of the delivery device puncturing the blood vessel wall.

[0049] Preferably, a buffer end is provided at the far end of the converging end, and the Shore hardness D of the buffer end is 50~80, such as 51, 55, 58, 63, 67, 73, etc.

[0050] Preferably, the material of the buffer end is a biocompatible polymer adhesive or solder paste, and more preferably includes UV-curable adhesive, epoxy resin adhesive or other polymer adhesives.

[0051] The buffer tip is used to cover any sharp edges that may exist at the converging tip, thereby effectively avoiding or minimizing damage to the blood vessel wall. By selecting an appropriate Shore hardness range, the buffer tip has good flexibility and elasticity, further reducing local pressure and irritation to the blood vessel wall, effectively minimizing damage and impact on the blood vessel wall, and improving safety during the implantation process.

[0052] In one optional embodiment, the force transmission network includes at least one circular array of lines arranged near the axis; the distal ends of the array lines of the circular array converge at the axis; the extension of the array lines toward the proximal ends is either regularly arranged or irregularly arranged.

[0053] Preferably, the force transmission network converges into a proximal convergence portion at its proximal end.

[0054] Preferably, the proximal convergence portion is positioned along the axial direction.

[0055] The proximal convergence into a proximal constriction facilitates the retraction of the delivery device into the microcatheter after stent implantation, and its subsequent removal from the body.

[0056] Preferably, the support delivery device further includes a pushing component connected to the proximal end of the force transmission network.

[0057] The pushing component is used to transmit the pushing force to the force transmission network.

[0058] Preferably, the pushing component includes any one or a combination of at least two of the following: a pushing guide wire and an axially extending deformable component;

[0059] Preferably, the axially extending deformable component includes any one or a combination of at least two of the following: a segmented expansion component and a helical wire structure.

[0060] In another specific embodiment, the support conveying device includes:

[0061] Axially extending push rod;

[0062] A force buffer component is disposed at the distal end of the push rod; the force buffer component includes at least one force transmission member, the force transmission member forming a non-zero angle with the axial center line of the push rod; the distance between the distal end of the force buffer component and the distal end of the bracket conveying device as a whole is less than or equal to the nominal diameter of the bracket conveyed by the bracket conveying device.

[0063] The force buffer component is configured such that when the axial thrust applied to the proximal end of the push rod causes the proximal end of the support conveying device to move axially by no more than half the axial length of the force transmission component, the force transmission component absorbs thrust fluctuations through elastic deformation; the force functional component is the force buffer component and / or the force transmission component.

[0064] Preferably, the force buffer component has a guide portion at its distal end.

[0065] The stent delivery device provided in this specific embodiment includes an axially extending push rod, which provides power for stent delivery and propels the stent along the vascular pathway. The distal end of the push rod is provided with a force-buffering component near or located at the distal end of the stent delivery device, including at least one force-transmitting member. The force-transmitting member forms a non-zero angle with the axial centerline of the push rod to ensure that the thrust is transmitted to the force-buffering component as quickly as possible and is effectively decomposed and buffered by the force-buffering component.

[0066] The force transmission component is typically pre-designed so that, without external force constraint, it forms a predetermined non-zero angle with the axial centerline of the push rod and tends to maintain or approach this angle. Inside the conduit, the force transmission component is constrained by the conduit wall, but because it still has a tendency to return to the predetermined angle, and because the conduit has a non-zero inner diameter, the force transmission component will still form a non-zero angle with the axial centerline of the push rod inside the conduit, but this angle is smaller than the predetermined angle.

[0067] During stent delivery, the stent and stent delivery device are located inside the catheter. Clinical procedures typically involve withdrawing the catheter and pushing the stent delivery device to release the stent at the target location. Unavoidable fluctuations in pushing force during these maneuvers can cause sudden forward movement of the guidewire or delivery structure distal to the stent delivery device, resulting in mechanical stimulation of the vessel wall. Even with minimal fluctuations in pushing force, the tortuous nature of the vascular pathway means that the transmission of force during pushing or withdrawing is affected by the vessel's curvature and friction, preventing the force from being transmitted 100% evenly to the distal end and impacting distal maneuverability.

[0068] In short, in practice, distal structures are prone to uneven thrust, causing them to come into contact with the blood vessel wall and even apply excessive local pressure, increasing the risk of blood vessel damage.

[0069] For lesions in bifurcated vessels, the risk of vessel puncture is greater. This is mainly because when a hemangioma is located at a vessel bifurcation, the distal end of the stent lands at the bifurcation, and its opening is perpendicular to the vessel wall on the opposite side of the bifurcation (referred to as the downstream vessel wall). After the distal end of the stent is released, the space that the distal end of the delivery device can extend is extremely limited. When this space cannot accommodate the withdrawal catheter and / or the sudden forward movement of the guidewire or delivery structure during the push of the stent delivery device, the distal end of the stent delivery device will exert a large-angle puncture force on the downstream vessel wall, increasing the risk of vessel puncture. Normally, the landing point of the distal end of the stent is located in the downstream region of the hemangioma. The diameter of the vessel in this region is usually smaller than the diameter of the vessel at the location of the hemangioma, approximately the nominal diameter of the stent to be implanted. In other words, the length of space that the distal end of the delivery device can extend is approximately within the range of the nominal diameter of the stent to be implanted. This application configures the stent delivery device such that when the axial thrust applied to the proximal end of the push rod causes the proximal end of the stent delivery device to move axially by no more than half the axial length of the force transmission member, the force transmission member can absorb thrust fluctuations through elastic deformation to ensure the stability of the distal thrust. The force buffering component can effectively reduce the force changes at the distal end, avoid sudden forward movement of the distal guidewire or delivery structure, and reduce mechanical stimulation to the blood vessel wall. Simultaneously, the distance between the distal end of the force buffer component and the distal end of the stent delivery device as a whole is limited to less than or equal to the nominal diameter of the stent delivered by the stent delivery device. This shortens the structural length of the stent delivery device located on the distal side of the force buffer component, forming a compact "headless" stent delivery device. Thus, even before the force buffer component is released, the protruding length of the distal end of the stent delivery device is minimized. By controlling this length within the nominal diameter of the stent to be delivered, the operability and safety of the delivery device in confined spaces such as distal blood vessels and bifurcation areas can be effectively improved, reducing the risk of accidental contact with the blood vessel wall and enhancing navigation ability and adaptability in narrow or highly tortuous blood vessels. It is particularly suitable for high-requirement clinical application scenarios such as bifurcation hemangiomas.

[0070] Specifically, this application incorporates a force buffer component to buffer the force exerted on the blood vessel wall by the distal end of the stent delivery device. This ensures that during the pulling and / or pushing process, the distal thrust remains within a controllable low range, effectively reducing mechanical stimulation to the blood vessel wall, lowering the risk of vascular injury caused by fluctuations in distal thrust, and improving the safety of the stent implantation process.

[0071] The force buffer component of this application can be understood as a structure capable of converting and absorbing the pushing force into deformation energy. Typical, but not limited, forms include springs, deformable spheres, deformable cages, etc. These structures can absorb excess pushing force through elastic deformation during the pushing process, ensuring a smoother transmission of pushing force at the distal end, thereby optimizing the stent release process, improving implantation accuracy, and reducing surgical complications caused by pushing force fluctuations.

[0072] This application does not specify the specific structure of the force buffer component; any structure with mechanical buffering capability known in the art can be used in this application.

[0073] Preferably, the structure of the force buffer component includes any one of a lantern-shaped mesh structure, a spiral structure, or a wave-shaped structure.

[0074] Preferably, in the unrestrained state, the angle between the distal end of the force transmission member and the axial centerline is 5~70°, such as 8°, 13°, 18°, 25°, 28°, 32°, 37°, 42°, 48°, 54°, 60°, 64°, 69°, etc.

[0075] In an unconstrained state, the angle between the force transmission component and the axial centerline is set to 5-70° to ensure that the force transmission component can effectively decompose and buffer the axial thrust during the pushing process. When a thrust is applied to the proximal end of the pushing rod, the thrust is transmitted axially to the force transmission component. Since the force transmission component forms a non-zero angle with the axial centerline, part of the thrust is decomposed along the direction of the component, causing it to undergo elastic deformation, thereby absorbing some thrust fluctuations. If the angle is too small (e.g., less than 5°), the axial force on the force transmission component is strong, and the deformation requires a large starting force, which may still generate large thrust fluctuations at the distal end, thus increasing the risk of distal end protrusion. If the angle is too large (e.g., more than 70°), the elastic deformation space of the force buffer component becomes smaller, the range of distal thrust fluctuations increases, and the force transmission component becomes too soft, resulting in a decrease in the axial rigidity of the force buffer component, which in turn affects the pushing efficiency. Therefore, the angle range of 5-70° achieves an optimized balance between buffering thrust and maintaining pushing rigidity, effectively absorbing thrust fluctuations without reducing the pushing performance of the conveying device.

[0076] However, it should be noted that although the preferred angle between the force transmission component and the axial centerline is 5-70°, this does not mean that angles less than 5° or greater than 70° cannot be used in this application. In appropriate application scenarios, angles exceeding the 5-70° range can still be considered as alternative technical solutions. For example, structures with an angle less than 5° are generally more suitable for situations where the blood vessel wall is more resilient or the distal pushing space is larger, while structures with an angle greater than 70° are suitable for situations where the blood vessel wall is less resilient or the distal pushing space is smaller.

[0077] In one specific embodiment, the force transmission component is made of a filamentous material with an elastic modulus of 30~180 GPa (e.g., 35GPa, 40GPa, 46GPa, 58GPa, 70GPa, 90GPa, 105GPa, 120GPa, 130GPa, 140GPa, 150GPa, 165GPa, 170GPa, 178GPa, etc.), preferably any one or a combination of at least two of the following: hyperelastic material and shape memory material.

[0078] Preferably, when the axial thrust applied to the proximal end of the push rod causes the distance by which the proximal end of the support conveying device moves axially to no more than half the axial length of the force transmission member, the axial thrust fluctuation at the distal end of the support conveying device is kept within ≤50mN, such as 45mN, 40mN, 36mN, 32mN, 26mN, 20mN, 18mN, 12mN, 8mN, 5mN, 2mN, etc.

[0079] The axial thrust fluctuation at the distal end of the stent delivery device is kept within ≤50mN, which can greatly reduce damage to the blood vessel wall, improve the delivery safety of the stent delivery device, and broaden the application scenarios of the stent delivery device, making it suitable for the treatment of bifurcation vascular lesions.

[0080] This application does not specifically limit the method for measuring axial thrust fluctuation. Typical but non-limiting methods include:

[0081] Simulating the actual vascular environment, the stent delivery device is pushed so that the distal end abuts against the distal force test position, and then pushed a predetermined distance at the proximal end. The force value at the distal end of the stent delivery device is measured and recorded to obtain the fluctuation range of the distal force value.

[0082] For example, a full-module push-back force tester can be used to simulate the actual vascular environment, and the force value at the distal end of the stent delivery device can be measured by a distal force sensor, wherein the distal force test position is the probe of the distal force sensor.

[0083] As one of the optional embodiments, the force buffer component is made of a material including a Nitinol alloy.

[0084] This application preferably uses filamentous materials with an elastic modulus of 30~180 GPa as the material for force transmission components. The elastic modulus reflects the deformation resistance of a material; materials within this range can provide sufficient deformation capacity while ensuring good elastic recovery.

[0085] In terms of specific material selection, superelastic materials or shape memory materials, or a combination of both, are preferred. For example, Nitinol alloy is a typical superelastic and shape memory alloy, exhibiting strong elastic deformation capacity within a small deformation range, enabling it to quickly absorb and release thrust fluctuations. Furthermore, Nitinol alloy can recover its original shape within a certain temperature range, allowing the force-buffering component to maintain a stable shape and function after stent deployment. The material properties of Nitinol alloy enable stent delivery devices to adapt to complex vascular environments and maintain good mechanical properties during clinical use.

[0086] In one specific implementation, the force buffer component is a lantern-shaped mesh structure. The lantern-shaped mesh structure is obtained by weaving multiple elastic threads into a hollow tube network structure and then pre-forming it into a structure where the two ends converge and the middle cavity is hollow. The elastic threads are force transmission components. Alternatively, the lantern-shaped mesh structure is obtained by extending at least two elastic threads side by side and pre-forming them into a structure where the two ends converge and the middle cavity is hollow. The elastic threads are force transmission components.

[0087] The lantern-shaped mesh structure is composed of multiple strands of elastic threads forming force-transmitting components, and is shaped by a pre-forming process to converge at both ends and form a cavity in the middle. Preferably, the force-transmitting components are distributed along the warp direction on the surface of the lantern-shaped structure, or extend at an angle to the warp direction.

[0088] The force-transmitting components are distributed along the meridian direction, meaning they extend from one end of the space frame along the meridian direction to the other, forming a regular axial support structure. This arrangement provides high axial rigidity and allows for elastic deformation along the meridian direction under stress, thus buffering thrust fluctuations.

[0089] The force transmission components are distributed at an angle to the meridian direction, providing more flexible deformation characteristics. During the pushing process, this angle design allows the thrust to be more easily decomposed into forces in multiple directions, enabling the lantern-shaped grid structure to more effectively distribute the load and thus improve the efficiency of thrust buffering.

[0090] In one specific embodiment, the cross-braided perforated network structure is formed by cross-weaving multiple strands of elastic yarn, creating multiple regular perforated mesh openings during the weaving process. The force-transmitting components extend and distribute at an angle to the warp direction. These mesh structures provide sufficient space for elastic deformation, allowing the force-buffering components to evenly distribute the load and generate controlled deformation when subjected to thrust, thereby effectively absorbing and buffering thrust fluctuations. This design ensures that even if the proximal thrust changes during stent delivery, the distal force remains within a relatively stable range, reducing the impact of distal protrusion on the vessel wall.

[0091] In another specific embodiment, the mesh structure formed by side-by-side arrangement of elastic threads consists of at least two elastic threads arranged side-by-side, forming a hollow structure with converging ends through a pre-shaped process. Force transmission components can extend along the warp direction on the surface of the lantern-shaped structure, or they can extend at a certain angle to the warp on the surface of the lantern-shaped structure. In this method, the arrangement of force transmission components is more regular, providing more stable force buffering characteristics. During the pushing process, the axial thrust is transmitted along the direction of the elastic threads. However, because the threads are distributed at a certain angle to the axial direction, part of the thrust is converted into a lateral component, causing controlled deformation of the force buffer components, thereby absorbing thrust fluctuations and preventing sudden increases in force at the distal end.

[0092] Preferably, the guide portion and the converging end of the force transmission component are designed as an integral part.

[0093] To further optimize the stability of the distal end of the lantern-shaped space frame structure, this application preferably provides a guide portion at the distal end of the force buffer component. The guide portion serves to guide the support during transport, enhancing the stability of the distal end of the transport device and reducing the probability of lateral offset or uncontrolled displacement of the distal structure during support release. The guide portion described in this application can be connected to the distal end of the converging end of the force transmission component via a connection method (such as bonding or welding), or the converging end can be directly extended as the guide portion. Preferably, the guide portion is designed integrally with the converging end of the force transmission component, making the structure more compact, reducing additional component connections, and improving overall mechanical performance.

[0094] This application optimizes the construction method of the lantern-shaped mesh structure, the arrangement of force transmission components, and the design of the guide section to ensure that the stent delivery device can effectively buffer thrust fluctuations during stent release, improve distal stability, reduce the risk of vascular injury, and optimize the accuracy of stent implantation during delivery and release.

[0095] As another specific implementation, the lantern-shaped grid structure is obtained by carving a metal tube into a hollow grid structure and then pre-forming it into a structure in which the two ends converge and the middle cavity is hollow, so that the support columns of the hollow grid are connected end to end to form a force transmission component.

[0096] By carving a hollowed-out space frame structure into metal tubes, the structural integrity of the space frame can be maintained, ensuring good mechanical properties and making force transmission more stable. In the hollowed-out space frame, the supports are connected end to end to form force transmission components. When a thrust is applied to the near end of the push rod, the thrust is transmitted along these supports. Due to the special design of the support structure, it can undergo elastic deformation during the stress process, thereby absorbing thrust fluctuations and reducing the instability of the thrust at the far end.

[0097] Preferably, the guide portion is integrated with the converging end of the force transmission component. To further enhance the remote stability of the conveying device, this application preferably provides a guide portion at the remote end of the force buffer component. The function of the guide portion is to stabilize the front trajectory of the conveying device and prevent deviation or uncontrolled displacement during the conveying process.

[0098] The guide section and the force transmission component are preferably designed as an integrated unit. That is, the guide section can be formed by extending the force transmission component or directly processed as an integrated structure, which improves the overall mechanical stability of the support conveying device and makes the conveying device more controllable during pushing and releasing.

[0099] Preferably, the hollowed-out mesh frame is prepared by laser engraving and / or chemical etching.

[0100] Laser engraving technology is applicable to a variety of high-performance metal materials, such as nickel-titanium alloys and cobalt-chromium alloys, and can ensure that force-absorbing components have excellent elastic deformation capabilities and long-term durability.

[0101] This application uses a lantern-shaped mesh structure formed by carving metal tubes, which can provide more stable and precise thrust control during stent delivery and release, reduce the risk of distal protrusion, and improve the safety and controllability of stent implantation.

[0102] In another specific embodiment, the force buffer component is an elastic structure pre-shaped into a spiral structure and / or a wave structure, and a guide portion is provided at the distal end of the force buffer component, the guide portion extending axially.

[0103] Preferably, the spiral structure and / or wavy structure are obtained through a predetermined process.

[0104] Both helical and / or wavy structures can undergo elastic deformation under axial force, thereby absorbing part of the thrust during the pushing process and reducing the fluctuation range of the far-end thrust.

[0105] The spiral structure consists of spiral components made of elastic material, which can be compressed or stretched axially during the pushing process, allowing the thrust to be decomposed and buffered within the spiral structure. The spiral shape design enables the force buffer component to gradually release the accumulated energy after being subjected to force, thereby avoiding the sudden transmission of thrust and improving the remote stability of the support conveying device.

[0106] The wave-like structure consists of multiple elastic components arranged in a wave pattern. During delivery, it undergoes controlled lateral deformation, distributing the thrust along the wave structure and absorbing thrust fluctuations through deformation. The wave-like structure provides a gentler force buffering effect, making it particularly suitable for stent delivery in tortuous blood vessels or areas of stenosis.

[0107] Compared to rigid linear force buffer structures, spiral or wave-shaped structures have superior flexible buffering characteristics, so that the proximal thrust is not directly and abruptly transmitted to the distal end, but is gradually released through the deformation of the buffer structure, thereby reducing the force fluctuation at the distal end and preventing the distal end of the delivery device from protruding or causing mechanical damage to the blood vessel wall.

[0108] To improve the trajectory stability of the support conveying device during the pushing and releasing process, especially the stability at the far end, this application provides an axially extending guide portion at the far end of the force buffer component, making it easier for the far end of the conveying device to maintain a stable pushing direction and reducing the probability of deviation or rotation.

[0109] Both the spiral and wave-shaped structures are obtained through a pre-designed process to ensure good deformation recovery during the pushing process and to maintain stable mechanical properties.

[0110] Preferably, the length of the guide portion is less than or equal to the nominal diameter of the support conveyed by the support conveying device. More preferably, the length of the guide portion is 0 to 0.8 times the nominal diameter of the support conveyed by the support conveying device, where 0 indicates that no guide portion is provided.

[0111] Preferably, the guide portion is sleeved on the distal end of the force buffer component, that is, the force transmission component of the force buffer component forms an extension portion at the converging end, and the guide portion is fixed to the outside of the extension portion.

[0112] This design improves the mechanical coordination between the guide section and the force buffer component. The guide section, fitted onto the distal end of the force buffer component, provides additional structural support, reducing the probability of unexpected lateral displacement or torsion of the distal structure during transport and release, thus improving the predictability and accuracy of the transport process. The presence of the guide section helps to evenly distribute the pushing force at the distal end, enabling the force buffer component to more stably absorb thrust fluctuations, further reducing thrust fluctuations at the distal end.

[0113] Preferably, the guide portion includes a rigid ring and / or a flexible ring; in specific implementations, the guide portion can adopt a rigid or flexible structure, the specific choice depending on the requirements of the target application scenario. Generally, in high-precision stent delivery requirements, a more rigid guide portion can be used to provide a more stable delivery trajectory; in tortuous vascular environments, a more compliant guide structure can be used to adapt to complex vascular morphology and reduce stress on the vascular wall.

[0114] Preferably, the rigid ring is a radiopaque ring; the rigid ring is typically made of radiopaque material, and its main function is to provide more stable distal support and enhance visibility under intraoperative image guidance. The rigid ring ensures that the guide portion is not easily deformed during delivery, thereby improving the distal rigidity of the delivery device and making stent release more controllable.

[0115] This application does not specifically limit the radiopaque material used; any radiopaque material available to those skilled in the art can be used to prepare the radiopaque ring, typically but not limited to platinum, platinum alloys, etc. These materials can be clearly visualized under X-rays or other medical imaging equipment, helping doctors to monitor the position of the delivery device and the release of the stent in real time during surgery, thus improving surgical precision.

[0116] Preferably, the flexible ring is a flexible single ring with a spiral winding structure, and more preferably a spiral coil.

[0117] The flexible ring is designed to provide better compliance and flexibility to accommodate the delivery needs of tortuous or vulnerable vessels. The flexible single ring can be made of highly elastic materials, providing some deformation capacity during delivery to reduce pressure on the vessel wall. Alternatively, a helical coil can be used as the primary form of the flexible ring. This structure offers excellent axial compliance and radial support, making it easier for the delivery device to pass through tortuous vessels while providing adequate support during stent deployment to prevent excessive distal protrusion.

[0118] Preferably, the guide portion is made of a radiopaque material. During interventional surgery, the radiopaque material allows the surgeon to observe the specific position of the guide portion in real time using imaging equipment such as X-rays, CT, or MRI, ensuring that the delivery device and stent are in the ideal implantation position, thereby improving the accuracy of implantation and the safety of the surgery.

[0119] In the preferred embodiment of this application, the structural design of the guide section is optimized to enable it to play an important role in stent delivery, intraoperative positioning, stent release, and vascular protection, thereby improving the overall performance of the stent delivery device and ensuring the efficiency and safety of interventional surgery.

[0120] In an optional embodiment, the distal end of the guide portion is provided with a buffer end, the buffer end having a Shore hardness D of 50~80, such as 55, 58, 63, 68, 75, etc., and a tensile property of 2%~150%, such as 3%, 16%, 33%, 55%, 73%, 95%, 113%, 135%, 148%, etc.

[0121] With a Shore hardness in the range of 50 to 80, the buffer end can maintain its shape when the guide is under load, while also having sufficient flexibility to deform when subjected to impact, absorb energy, and reduce damage to surrounding structures or biological tissues.

[0122] Tensile properties indicate a material's ability to stretch under tensile force. A range of 2% to 150% allows the material to meet deformation requirements, withstanding both minor deformations and significant tensile stresses without fracture. This enables the buffer end to move more easily through tortuous blood vessels during transport, improving its adaptability under dynamic loads and overall durability.

[0123] Preferably, the material of the buffer end is a biocompatible polymer adhesive or solder paste, and more preferably includes UV-curable adhesive or epoxy resin adhesive.

[0124] The second objective of this application is to provide a support system, comprising:

[0125] One of the purposes is the support conveying device described above;

[0126] The support is mounted at the distal end or near the distal end of the support delivery device according to any one of claims 1 to 16.

[0127] The distal end of the support delivery device is positioned as close as possible to the distal end of the support to provide better pushing performance.

[0128] Preferably, the bracket is fitted onto the bracket conveying device described in the purpose of the conveying state, and the distal end of the bracket is disposed outside the force-functioning component.

[0129] The stent has a self-expanding characteristic, and its distal end is located outside the force function component, which enables a radial force to be generated on the stent at the moment the force function component is released, thus assisting the stent to open.

[0130] Preferably, in the conveying state, the distal end of the bracket is located on the outside near the distal end of the force-function component.

[0131] In a preferred embodiment, the position extending axially a predetermined distance from the distal end of the support is defined as the extreme position, and the distal end of the support delivery device is located on the proximal side of the extreme position; the predetermined distance is 0.8 to 1 times the nominal diameter of the support.

[0132] This application achieves improved operability and safety by positioning the stent delivery device at an extreme position (i.e., 0.8 to 1 times the nominal diameter of the distal side of the stent to be delivered) on the proximal side. This positioning reduces the potential risk of damage to the vessel wall from the stent delivery device during stent delivery, deployment, and implantation.

[0133] During stent selection, a stent is typically chosen based on the diameter of the vessel at the lesion site. The nominal diameter of the stent is usually slightly larger than the diameter of the diseased vessel to ensure that it can effectively guide blood flow or restore vascular patency after implantation. Human blood vessels originate from the ventricles and branch into increasingly smaller vessels. Given this anatomical structure, placing the distal end of the stent delivery device at its extreme position provides sufficient pushing force and guidance to ensure precise stent delivery to the target site. It also allows for better utilization of the space provided by the vessel on the opposite side of the bifurcation in cases of bifurcation lesions, avoiding excessive pressure on the vessel wall.

[0134] Preferably, with the far end of the support to be transported as the zero point, the far end of the support transport device is located within the range of -5mm to + the nominal diameter of the support to be transported.

[0135] Optionally, the distal end of the support to be transported has an open-loop structure, with the distal end of the support to be transported as the 0 point, and the distal end of the support transport device is located within the range of 0~+5mm from the distal end of the support to be transported.

[0136] Optionally, the distal end of the support to be transported is a closed-loop structure, with the distal end of the support to be transported as the 0 point, and the distal end of the support transport device is located within the range of -5mm to +5mm from the distal end of the support to be transported.

[0137] Preferably, with the far end of the support to be transported as the zero point, the far end of the support transport device is located near the far end of the support to be transported, and the support to be transported is a support with a closed loop at the far end; the support to be transported is preferably a cobalt-chromium alloy support.

[0138] When the distal end of the stent delivery device is located proximal to the distal end of the stent to be delivered, insufficient delivery and reduced guidance may occur because the distal end of the stent is not supported by the delivery device during delivery. To overcome this deficiency, this application designs the stent to be delivered as a distal closed-loop structure, which can effectively improve delivery performance and ensure better shape stability. Specifically, with a closed-loop design at the distal end of the stent, excellent delivery performance can be maintained during delivery, and shape stability can be maintained without the load of the delivery device, avoiding stent deformation, thereby improving guidance capability and ensuring successful stent implantation in complex vascular pathways.

[0139] The term "remote closed loop" refers to the use of a closed loop structure at the distal end of the stent, which means that through a specific design, the metal wires or other materials at the distal end of the stent form a closed loop structure in the axial direction.

[0140] Preferably, the support to be transported is a cobalt-chromium alloy support.

[0141] Preferably, the support conveying device includes any one or a combination of at least two of the following: a wire braided structure and a carved hollow structure.

[0142] The combination of at least two typically, but not limited to, includes combinations of proximal guidewire distal wire braided structures and combinations of proximal guidewire distal engraved hollow structures. The braided and engraved hollow structures can, exemplarily, be formed into a structure with a "large internal space in the middle and tightened ends" shape through a heat-setting process.

[0143] The braided structure is typically created by cross-weaving metal wires into a tubular network, which is then heat-set to form a structure with a large internal space and constricted ends. Examples of the cross-weaving of the metal wires into a tubular network structure include any one of the following: a one-up-one-down braiding method, a two-up-two-down braiding method, a double-strand composite braiding method, or a three-strand composite braiding method.

[0144] The engraved hollow structure is constructed by engraving a metal tube into a hollow structure, binding both ends, and then heat-setting it into a structure with a large internal space in the middle and bound ends. The engraving method exemplarily includes laser engraving. This application does not specifically limit the hollow pattern of the engraved hollow structure; any hollow pattern that can be heat-set into a structure with a large internal space in the middle and bound ends can be used in this application.

[0145] In one alternative technical solution, at least the distal end of the support conveying device is a braided structure with the elastic modulus of the braid ≤180 GPa, preferably 30~80 GPa.

[0146] In another alternative technical solution, at least the distal end of the support conveying device is a carved hollow structure, and the elastic modulus of the support column constituting the hollow structure is ≤180 GPa, preferably 30~80 GPa.

[0147] In short, this application does not impose specific limitations on the selection of stent delivery devices. Any known or new delivery device that can achieve stent delivery can be used in this application. However, selecting a structure composed of a basic structure (such as a wire or strut) with an elastic modulus of less than 180 GPa as the preferred option for the distal end of the stent delivery device can better reduce stimulation and damage to the blood vessel wall.

[0148] Preferably, the stent delivery device includes a proximal pushing part and a distal flexible part, wherein the elastic modulus of the distal flexible part is ≤180 GPa.

[0149] The flexible portion has a low elastic modulus, which effectively reduces irritation and damage to the blood vessel wall upon contact. The flexible portion may be composed of a woven yarn structure and / or a sculpted, openwork structure.

[0150] Preferably, the elastic modulus of the material at the distal end of the stent delivery device is lower than that of the material at the proximal end of the stent delivery device. Using different elastic moduli for the materials at the distal and proximal ends of the stent delivery device allows for improved delivery capability while ensuring low irritation and minimal damage to the blood vessel wall at the distal end.

[0151] Preferably, the distal end of the stent delivery device includes a non-transparent material structure to enable visualization of the distal end of the stent delivery device.

[0152] In yet another preferred embodiment, the support system includes:

[0153] Self-expanding stent;

[0154] catheter;

[0155] A stent delivery device according to one embodiment of the objective is disposed within the conduit and extends axially, wherein the stent delivery device loads the stent at its distal end and is used to receive a pushing force and transmit the pushing force to the distal end; the distal end of the stent is defined as point X.

[0156] On the stent delivery device, a force change point A is provided at a predetermined axial distance from the proximal side of point X; a force buffer component is provided at the distal side of the force change point A, so that after the force change point A of the stent delivery device extends beyond the distal end of the conduit, the pushing force fluctuation range transmitted to the distal end is ≤50mN within a range of no more than 1.5mm of the proximal end advance displacement of the stent delivery device; the predetermined distance is ≥1.5mm.

[0157] During stent delivery, once the stent reaches the vicinity of the lesion, stent release is typically controlled by withdrawing the catheter and advancing the stent delivery device. However, during this process, the pulling and / or pushing forces applied to the stent delivery device proximally are transmitted to the distal end. Due to the tortuous nature of the blood vessel, these forces are lost during transmission, resulting in a weakened distal response and reduced controllability. Furthermore, the tortuous vascular structure may cause the distal end of the stent delivery device to come into contact with the vessel wall or even apply additional pressure, thereby increasing the risk of vascular injury. This application addresses this issue by incorporating a force-buffering component at the distal end of the stent delivery device to buffer the forces applied to the vessel wall, controlling their fluctuation to ≤50mN. This ensures that the force on the distal end remains within a controllable range during advancement or withdrawal, reducing irritation and damage to the vessel wall and improving the safety of stent implantation.

[0158] When the stent delivery device is advanced a specific distance Y proximally, factors such as vascular tortuosity often cause a loss in the advancement stroke, resulting in the actual distal advancement distance being less than Y. To ensure the effectiveness of the force buffer component, this application limits the predetermined distance to ≥1.5mm to ensure that the force buffer component can be fully released and function. When point A of the stent delivery device extends beyond the distal end of the catheter, as long as the distal advancement displacement is within the range of 0~1.5mm, the force fluctuation on the vessel wall can be ensured to be ≤50mN. Furthermore, considering the existence of advancement stroke loss, the actual proximal advancement distance can usually exceed 1.5mm without affecting the function of the force buffer component.

[0159] In the stent system, the force buffer component of the stent delivery device is positioned near the distal end. After the stent is delivered to the distal end of the lesion, the operator begins pushing and / or withdrawing the stent, gradually releasing the stent and the distal end of the stent delivery device. When the force change point A extends beyond the distal end of the catheter, the force buffer component is fully released. At this point, as long as the proximal advancement displacement does not exceed 1.5 mm, the fluctuation range of the pushing force transmitted to the distal end can be ensured to be ≤50 mN. Simultaneously, since the force buffering range of the force buffer component does not exceed half the axial length of the force transmission component, the distal end of the stent is typically flush with the distal end of the force buffer component, or located between the proximal and distal ends of the force buffer component. This assists in better stent deployment during the initial stage of stent release. More importantly, the predetermined distance of ≥1.5 mm ensures that after the force change point A extends beyond the distal end of the catheter, there is sufficient axial space for the force buffer component, giving the force transmission component sufficient length to buffer and distribute the force on the distal end of the stent delivery device.

[0160] It should be noted that during stent delivery, the stent delivery device is typically under axial tension and radial compression. Only when the stent delivery device extends partially or completely beyond the catheter will the release portion undergo axial contraction and radial expansion to adapt to the intravascular environment and complete stent implantation.

[0161] Preferably, the axial length of the force transmission component is ≥3.0mm.

[0162] The axial length of the force transmission component is ≥3.0mm. After the force change point A extends beyond the conduit, the distance between X and A will be greater than or equal to 3.0mm. This can effectively ensure that after the force change point A of the stent delivery device extends beyond the far end of the conduit, the advance displacement of the stent delivery device at the proximal end is within the range of no more than 1.5mm and does not exceed half the axial length of the force transmission component.

[0163] Preferably, the distal end X of the stent to be delivered is located between the force change point A and the distal end of the force buffer component. Positioning the distal end of the stent to be delivered in a suitable location can, on the one hand, reduce the risk of the stent delivery device extending too far beyond the stent's distal end during stent release, thus preventing damage to the blood vessel wall and increasing the operational space of the distal end of the stent delivery device; on the other hand, it can improve the controllability of stent delivery, especially the controllability of the distal end.

[0164] Compared with the prior art, this application has the following beneficial effects:

[0165] (1) This application provides a stent delivery device, which, by setting a force function component, effectively decomposes or redirects the reaction force generated when the distal end of the delivery device touches the blood vessel wall during stent implantation, significantly reducing the force exerted by the stent delivery device on the blood vessel wall during stent implantation and reducing the risk of blood vessel wall puncture.

[0166] (2) Setting the distance between the distal end of the force function component and the distal end of the stent delivery device as less than or equal to the nominal diameter of the stent delivered by the stent delivery device not only ensures that the distal end of the stent can land safely when it is initially released, but also further reduces the possibility of vascular injury during the stent release process, thereby improving the safety and accuracy of stent implantation. Attached Figure Description

[0167] Figure 1 is a structural schematic diagram of the force transmission network 200 of the support conveying device provided in Embodiment 1 from the perspective of the axis point;

[0168] Figure 2 is a structural schematic diagram of the support conveying device provided in Embodiment 1;

[0169] Figure 3 is a structural schematic diagram of the force transmission network 200 of the support conveying device provided in Embodiment 2 from the perspective of the axis point;

[0170] Figure 4 is a structural schematic diagram of the support conveying device provided in Embodiment 2;

[0171] Figure 5 is a structural schematic diagram of the force transmission network 200 of the support conveying device provided in Embodiment 3 from the perspective of the axis point;

[0172] Figure 6 is a structural schematic diagram of the support conveying device provided in Embodiment 4;

[0173] Figure 7 is a schematic diagram of the stent delivery device in the stent system provided in Application Example 1, where the catheter is not extended.

[0174] Figure 8 is a schematic diagram of the stent delivery device extending from the conduit in the stent system provided in Application Example 1.

[0175] Figure 9 shows the measurement results of the pushing force fluctuation range at the distal end of the support conveying device provided in Example 4;

[0176] Figure 10 is a structural schematic diagram of the support conveying device provided in Embodiment 5;

[0177] Figure 11 shows the measurement results of the pushing force fluctuation range at the distal end of the support conveying device provided in Example 5;

[0178] Figure 12 is a structural schematic diagram of the support conveying device provided in Embodiment 6;

[0179] Figure 13 shows the measurement results of the pushing force fluctuation range at the far end of the support conveying device provided in Example 6;

[0180] Figure 14 is a structural schematic diagram of the support system provided in Embodiment 7;

[0181] Figure 15 is a schematic diagram of the distal open-loop stent;

[0182] Figure 16 is a structural schematic diagram of the support system provided in Embodiment 8. Detailed Implementation

[0183] The technical solution of the present invention will be further explained and described below with reference to specific embodiments. However, it should be noted that the specific embodiments are only a specific implementation and explanation of the essence of the technical solution of the present invention, and should not be construed as a limitation on the scope of protection of the present invention.

[0184] In the description of this invention, it should be understood that the terms "distal" and "proximal" should be understood as referring to the end viewed from the surgeon's perspective; "distal" is the end furthest from the surgeon, while "proximal" is the end closest to the surgeon. The term "axial" refers to the direction of stent delivery, "axial direction" refers to the axial extension direction, and "center point" is the intersection of the axial direction and any cross-section perpendicular to the axial direction.

[0185] The present application will now be described in further detail with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and not intended to limit it. Furthermore, it should be noted that, for ease of description, only the parts relevant to the invention are shown in the accompanying drawings.

[0186] Example 1

[0187] As shown in Figures 1 and 2 (Figure 1 is a structural schematic diagram of the force transmission network 200 of the support conveying device provided in Embodiment 1 from the angle of the axis point, and Figure 2 is a structural schematic diagram of the support conveying device provided in Embodiment 1), a support conveying device includes a push rod 110 (1.5m in length) and a force transmission network 200 disposed at the far end of the push rod 110;

[0188] The force transmission network 200 includes six straight array lines 202 (3 mm in length), with the distal end bound by a spiral coil to form a converging end 203 (2.3 mm in length), and the proximal end converging within the developing ring 300. Both the proximal and distal ends of the force transmission network 200 are positioned along the axial direction. The array lines 202 are made of nitinol alloy wire (0.046 mm in diameter, Shore hardness D of 60). The force transmission network 200 is heat-set to form a structure with a large internal space in the middle and constricted ends, thus obtaining the shape of the force transmission network 200.

[0189] The support conveying device can convey supports of any nominal diameter, preferably supports with a nominal diameter of 2.3~5.6mm. The ratio of the length of the converging end to the length of the force transmission network under constrained state is 0.77:1.

[0190] The distal force of the stent delivery device provided in Example 1 was tested using a full-module push-pull force meter (model RXDZ-TLN02G 10MMW, including a distal force sensor). The test method involved measuring the proximal push force and distal force when the proximal end was pushed 2mm. The results showed that the proximal push force ranged from 40 to 100 mN, and the distal force ranged from 10 to 17 mN. It can be seen that the stent delivery device provided in this application effectively reduces the distal force and minimizes damage to blood vessels.

[0191] In other embodiments, the length of the converging end 203 may be less than or equal to the nominal diameter of the support to be transported.

[0192] In other schemes, the angle between the extension direction of the elastic thread at the distal end and the axial direction can be selected to be any angle from 0 to 80° (excluding 0°); the ratio of the length of the converging end to the length of the force transmission network under the bound state can also be any value in the range of 0:1 to 0.8:1 (excluding 0:1).

[0193] In a preferred embodiment, the distal end of the converging end 203 is provided with a buffer end 123, which is formed by shaping a convex surface from a biocompatible polymer adhesive, and the Shore hardness D of the buffer end 123 is 50~80.

[0194] The support conveying device provided in Example 1 achieves an angle α of 24° between the array line 202 and the axial direction when there is no external force constraint. This is achieved through heat setting, that is, the array line 202 is shaped to have an angle of 24° with the axial direction through heat setting.

[0195] Example 2

[0196] As shown in Figures 3 and 4 (Figure 3 is a structural schematic diagram of the force transmission network 200 of the support conveying device provided in Embodiment 2 from the angle of the axis point, and Figure 4 is a structural schematic diagram of the support conveying device provided in Embodiment 2), a support conveying device includes a push rod 110 (1.5m in length) and a force transmission network 200 disposed at the far end of the push rod 110. The force transmission network 200 includes a first arrangement structure 210 and a second arrangement structure 220.

[0197] The first arrangement structure 210 includes four first curved array lines 212 (5 mm in length), and the second arrangement structure 220 includes four second curved array lines 222 (5 mm in length). The distal ends of the first curved array lines 212 and the second curved array lines 222 are bound together and converge at a point 203 (1.5 mm in length) by a spiral coil. The proximal ends of the first curved array lines 212 and the second curved array lines 222 are bound together and converged within the developing ring 300. The first curved array lines 212 and the second curved array lines 222 are interwoven into a grid pattern.

[0198] The first curved array line 212 and the second curved array line 222 are made of nickel-titanium alloy wire (wire diameter 0.046 mm, Shore hardness D 60). The force transmission network 200 is heat-set into a structure with a large internal space in the middle and tightened at both ends to obtain the shape of the force transmission network.

[0199] The support conveying device can convey supports of any nominal diameter, preferably supports with a nominal diameter of 1.5~5.6mm. The angle between the extension direction of the array line at the distal end and the axial direction is 10°, and the ratio of the length of the converging end to the length of the force transmission network under constrained state is 0.30:1.

[0200] The distal force of the stent delivery device provided in Example 2 was tested using a full-module push-pull force meter and a distal force sensor. The test method involved measuring the proximal push force and distal force values ​​when the proximal end was pushed 2 mm. The results showed that the proximal push force was 45-60 mN, and the distal force value was 10-13 mN. It can be seen that the stent delivery device provided in this application effectively reduces the distal force value, reduces damage to blood vessels, and significantly reduces the fluctuation range of its distal push force and distal force value, exhibiting a more stable pushing effect.

[0201] In an optional embodiment, the push rod 110 includes a proximal push rod and an axially extending deformation member disposed at the distal end of the push rod. The proximal end of the force transmission network 200 is connected to the distal end of the axially extending deformation member. The axially extending deformation member can be configured as a segmental convergence member, achieved by convergence of a pre-shaped tubular structure. The tubular structure can be obtained by pre-shaping and convergence at both ends of a metal tube after weaving or laser engraving. In an optional embodiment, the array lines of the force transmission network can be extended and woven based on the above dimensions.

[0202] In a preferred embodiment, the length of the converging end 203 is less than or equal to the nominal diameter of the support to be transported.

[0203] In other schemes, the angle between the extension direction of the array line at the far end and the axial direction can be selected to be any angle from 0 to 80° (excluding 0°); the ratio of the length of the converging end to the length of the force transmission network under the bound state can also be any value in the range of 0:1 to 0.8:1 (excluding 0:1).

[0204] In a preferred embodiment, the distal end of the converging end 203 is provided with a buffer end 123, which is formed by shaping a convex surface from a biocompatible polymer adhesive. The Shore hardness D of the buffer end 123 is 50~80, and the tensile properties are 2%~150%.

[0205] Example 3

[0206] As shown in Figure 5 (Figure 5 is a structural schematic diagram of the force transmission network 200 of the support conveying device provided in Embodiment 3 from the angle of the axis point), a support conveying device includes a push guide wire (1.5m in length, not shown in the figure) and a force transmission network 200 disposed at the distal end of the push guide wire;

[0207] The force transmission network 200 includes five straight array lines 202 (7 mm in length), with the distal end bound by a spiral coil to form a converging end 203 (1.05 mm in length), and the proximal end converging within the developing ring 300. Both the proximal and distal ends of the force transmission network 200 are positioned along the axial direction. The array lines 202 are made of nitinol alloy wire (0.046 mm in diameter, Shore hardness D of 60). The force transmission network 200 is heat-set to form a structure with a large internal space in the middle and constricted ends, thus obtaining the shape of the force transmission network 200.

[0208] The support conveying device can convey supports of any nominal diameter, preferably supports with a nominal diameter of 1.05~5.6mm. The angle between the extension direction of the array line at the distal end and the axial direction is 80°, and the ratio of the length of the converging end to the length of the force transmission network under constrained state is 0.15:1.

[0209] The distal force of the stent delivery device provided in Example 3 was tested using a full-module push-pull force meter and a distal force sensor. The test method involved measuring the proximal push force and distal force values ​​when the proximal end was pushed 2 mm. The results showed that the maximum proximal push force was 40~100 mN, and the maximum distal force was 9~18 mN. The stent delivery device provided in this application effectively reduces the distal force value and reduces damage to blood vessels.

[0210] In other embodiments, the length of the converging end 203 may be less than or equal to the nominal diameter of the support to be transported.

[0211] In other schemes, the angle between the extension direction of the array line at the far end and the axial direction can be selected to be any angle from 0 to 80° (excluding 0°); the ratio of the length of the converging end to the length of the force transmission network under the bound state can also be any value in the range of 0:1 to 0.8:1 (excluding 0:1).

[0212] In a preferred embodiment, the distal end of the converging end 203 is provided with a buffer end, which is formed by shaping a convex surface from a biocompatible polymer adhesive, and the Shore hardness D of the buffer end is 50~80.

[0213] The support conveying device provided in Example 3 achieves an 80° angle between the array line 202 and the axial direction when there is no external force constraint through heat setting, that is, the array line 202 is shaped to have an 80° angle with the axial direction through heat setting.

[0214] For comparison, a full-module push-back force meter and a distal force sensor were used to test the distal force of the stent delivery device provided by the 1.6m delivery guidewire. The test method was to measure the proximal push force and distal force when the proximal end was pushed 2mm. The results showed that the maximum proximal push force was 140~170mN, and the maximum distal force was 48~90mN. It can be seen that the distal force value is significantly higher when relying solely on the guidewire for stent delivery, which increases the risk of vascular puncture.

[0215] The stent delivery device with force transmission network 200 described in this application is used in the treatment of bifurcation hemangiomas as follows:

[0216] (1) The stent 900 is held against the force transmission network 200 at the distal end of the stent delivery device and is loaded inside the microcatheter 800; the push rod 110 of the stent delivery device extends proximally outside the body;

[0217] (2) Pushing rod 110 of the stent delivery device pushes the stent 900 to the hemangioma lesion. After the distal end of the stent 900 reaches the stent anchoring point (normal blood vessel) at the distal end of the lesion, the microcatheter 800 is withdrawn. The stent 900 expands radially, and the force transmission network 200 undergoes radial expansion deformation. However, since the radial expansion of the force transmission network 200 is smaller than the radial expansion size of the stent 900, the distal end of the stent delivery device is likely to extend beyond the distal end of the stent 900 and approach the downstream blood vessel wall of the bifurcation hemangioma. Since the force transmission network 200 is provided with several array lines that deviate from the axial direction, the force generated by approaching is decomposed into axial force and deviated axial force, which reduces the damage to the blood vessel wall. At the same time, the deformation of the array lines also cancels out the corresponding force, further reducing the damage to the blood vessel wall.

[0218] Example 4

[0219] As shown in Figure 6 (Figure 6 is a structural schematic diagram of the support conveying device provided in Embodiment 4), Embodiment 4 provides a support conveying device 100, including:

[0220] Axially extending push rod 110;

[0221] A force buffer component is disposed at the distal end of the push rod 110; the force buffer component is a lantern-shaped mesh structure 120, which in its natural state has a structure in which the two ends converge and the middle cavity is hollow. The lantern-shaped mesh structure 120 is formed by laser engraving a hollow pattern on a metal tube, and then pre-shaping it by heating to obtain a structure in which the two ends converge and the middle expands. The frame pillars of the hollow pattern are connected end to end to form a force transmission component 1211; the proximal end of the lantern-shaped mesh structure 120 is fixedly connected to the distal end of the push rod 110, and a spiral coil 132 is wound around the distal end of the lantern-shaped mesh structure 120. The distal end of the spiral coil 132 is cured with ultraviolet light curing adhesive (model S2000-XLA) to serve as a buffer end 123. The spiral coil 132 and the buffer end 123 together serve as a guide.

[0222] The hollowed-out pattern includes four meridional columns 121a and connecting beams 121b connecting adjacent meridional columns 121a. The connecting beams 121b are S-shaped, and both ends of the connecting beams 121b are connected to the adjacent meridional columns 121a. The meridional columns 121a are force transmission components 1211.

[0223] In the lantern-shaped grid structure 120 formed after pre-molding, the angle between the force transmission member 1211 and the axial centerline is 40°. The metal tube is a nickel-titanium alloy metal tube with an elastic modulus of 30~75GPa.

[0224] Application Example 1

[0225] As shown in Figures 7 and 8 (Figure 7 is a schematic diagram of the stent delivery device in the stent system provided in Application Example 1 before it extends out of the conduit, and Figure 8 is a schematic diagram of the stent delivery device in the stent system provided in Application Example 1 with the stent delivery device extended out of the conduit), Application Example 1 provides a stent system, including:

[0226] The stent 900 (nominal diameter 3.2 mm), the catheter 300, and the stent delivery device 100 provided in Embodiment 4 extend inside the catheter 300, and the self-expanding stent 900 is mounted on the distal end of the stent delivery device 100; the proximal end of the force buffer component of the stent delivery device 100 is point A, and the length of the force buffer component in the expanded state is 3.0 mm; the distal end of the self-expanding stent 900 is point X, and the distal end (point X) of the self-expanding stent 900 is located near the location of the buffer end 123.

[0227] During operation, the operator pushes the push rod 110 of the stent delivery device 100 or retracts the conduit 300, causing the distal end of the stent delivery device 100, which carries the self-expanding stent 900, to extend beyond the conduit 300. When point A of the stent delivery device 100 extends beyond the distal end of the conduit, the force buffer component is fully released and enters a natural state (both ends are constricted and the middle cavity is empty). At this time, when the proximal end of the push rod 110 pushes a distance within 1.5mm, the pushing force fluctuation range of the distal end of the stent delivery device 100 is 0~20mN, which can be controlled within 50mN.

[0228] The pushing force transmission characteristics of the support conveying device provided in the following embodiments were tested using a full-module pushing and pulling force tester (model RXDZ-TLN02G 10MMW). The specific steps are as follows:

[0229] (1) Assembly test system: Assemble the stent delivery device to be tested into the distal end of the microcatheter; fix the microcatheter in the test path of the full module push-back force tester to ensure that its path simulates the bending characteristics of the actual vascular environment, arrange the distal force sensor at the distal end of the test path, push the stent delivery device to be tested so that the force buffer component just extends out of the microcatheter and its distal end abuts against the probe of the distal force sensor to detect the change in the push force transmitted to the distal end.

[0230] (2) Test execution: The proximal pushing mechanism of the full module push-back force tester applies an axial thrust to the stent delivery device, and records the force value detected by the remote force sensor when the far end of the stent delivery device reaches the remote force sensor. The push displacement is within half the axial length of the force transmission component (1.5 mm in Examples 1 to 3, and 2.5 mm in Example 4).

[0231] According to the test method, the measurement results of the pushing force fluctuation range at the distal end of the stent delivery device provided in Example 4 are shown in Figure 9. The Proximal line is the proximal force value detection value, and the Distal line is the distal force value detection value.

[0232] Example 5

[0233] As shown in Figure 10 (Figure 10 is a structural schematic diagram of the support conveying device provided in Embodiment 5), Embodiment 5 provides a support conveying device 100, which differs from Embodiment 4 only in the structural arrangement of the force buffer component, specifically:

[0234] A force buffer component is located at the distal end of the push rod 110 (the full length of the push rod 110 is not shown in Figure 10). The lantern-shaped mesh structure 120 has a structure in its natural state where the two ends converge and the middle cavity is hollow. The lantern-shaped mesh structure 120 is formed by cross-weaving eight elastic threads 121c into a hollow tube structure. After the two ends are gathered and brought close together to expand the middle cavity, it is pre-shaped by heating. The unbound part of the elastic threads 121c is the force transmission component 1211. After the two ends of the tube structure are gathered, the proximal end is fixed to the distal end of the push rod 100. The distal end is wound with a spiral coil 132, and the distal end of the spiral coil 132 is cured with UV-curable adhesive (model S2000-XLA) to serve as a buffer end 123. The spiral coil 132 and the buffer end 123 together serve as a guide.

[0235] In the lantern-shaped mesh structure 120 formed after pre-molding, the force transmission member 1211 has an angle of 20° with the axial center line, and the force transmission member 1211 extends and is distributed at a certain angle (60°) with the warp direction of the lantern-shaped mesh structure. The elastic wire 121c is a nickel-titanium metal wire with an elastic modulus of 30-75 GPa.

[0236] The buffer end 123 has a Shore hardness D of 50~75 and a tensile strength of 50%~150%; the spiral coil 132 is made of radiopaque material and has an axial length of 3mm.

[0237] In other optional embodiments, the elastic filament 121c may also be selected from filamentous materials with an elastic modulus of 30~180 GPa, such as superelastic materials, shape memory materials, etc., typically but not limited to metal filaments such as nickel-titanium alloys and cobalt-chromium alloys, polymer filaments with shape memory, or metal filaments or polymer filaments coated with functional coatings.

[0238] Application Example 2

[0239] The only difference from Application Example 1 is that the support conveying device 100 provided in Example 4 is replaced with the support conveying device provided in Example 5.

[0240] The test method is the same as the test example, except that the stent delivery device provided in Example 4 is replaced with the stent delivery device provided in Example 5. When the proximal end of the push rod 110 is pushed within a distance of 1.5 mm, the pushing force fluctuation range of the distal end of the stent delivery device 100 is 0~10 mN, which can be controlled within 50 mN. According to the test method of the test example, the measurement results of the pushing force fluctuation range of the distal end of the stent delivery device provided in Example 5 are shown in Figure 11. The Proximal line is the proximal force value detection value, and the Distal line is the distal force value detection value.

[0241] Example 6

[0242] As shown in Figure 12 (Figure 12 is a structural schematic diagram of the support conveying device provided in Embodiment 6), Embodiment 6 provides a support conveying device 100, which differs from Embodiment 1 only in the structural arrangement of the force buffer component, specifically:

[0243] A force buffer component is located at the distal end of the push rod 110. The force buffer component is a lantern-shaped mesh structure 120. In its natural state, the lantern-shaped mesh structure 120 has a structure in which the two ends converge and the middle cavity is hollow. The lantern-shaped mesh structure 120 is formed by arranging 6 elastic threads 121c side by side into a tubular structure. After the two ends are gathered together and brought close together to expand the middle cavity, it is pre-shaped by heating. The unbound part of the elastic threads 121c is the force transmission component 1211. After the two ends of the tubular structure are gathered together, the proximal end is fixed to the distal end of the push rod 100. The distal end is wound with a spiral coil 132, and the distal end of the spiral coil 132 is cured with UV-curable adhesive (model S2000-XLA) to serve as a buffer end 123. The spiral coil 132 and the buffer end 123 together serve as a guide.

[0244] In the pre-formed lantern-shaped mesh structure 120, the force transmission member 1211 forms an angle of 30° with the axial centerline, and the force transmission member 1211 is distributed along the warp direction on the surface of the lantern-shaped mesh structure. The elastic wire 121c is a nickel-titanium metal wire with an elastic modulus of 30-75 GPa.

[0245] Application Example 3

[0246] The only difference from Application Example 1 is that the support conveying device 100 provided in Example 1 is replaced with the support conveying device provided in Example 6.

[0247] The test method is the same as in Application Example 1, except that the stent delivery device provided in Example 1 is replaced with the stent delivery device provided in Example 6. When the proximal end of the push rod 110 is pushed a distance of 1.5 mm, the pushing force fluctuation range of the distal end of the stent delivery device 100 is 0~33 mN, which can be controlled within 50 mN. According to the test method of the test example, the measurement results of the pushing force fluctuation range of the distal end of the stent delivery device provided in Example 6 are shown in Figure 13. The Proximal line is the proximal force value detection value, and the Distal line is the distal force value detection value.

[0248] Example 7

[0249] As shown in Figure 14 (Figure 14 is a structural schematic diagram of the stent system provided in Embodiment 7, and Figure 15 is a structural schematic diagram of the distal open-loop stent), a stent system includes:

[0250] The stent delivery device includes a proximal push guide wire 110 and a distal flexible part 130. The distal flexible part includes a braided wire structure 131 connected to the distal end of the proximal push guide wire 110 and a non-transparent spiral coil 132 disposed at the distal end of the braided wire structure 131. The braided wire structure 131 is formed by cross-braiding metal wires into a tubular network structure, binding the two ends, and then heat-setting it into a structure with a large internal space in the middle and tight ends. The elastic modulus of the wires in the braided wire structure 131 is 60 GPa (in other embodiments, any wire in the range of 50~70 GPa can be selected). The elastic modulus of the non-transparent spiral coil 132 is 165 GPa.

[0251] The support 900 to be transported (nominal diameter of 2.3 mm) is pressed onto the distal flexible part 130, and in the transport state, the distal end of the distal flexible part 130 is located 2.3 mm from the distal end of the support 900 to be transported; the support 900 to be transported is a distal open-loop support.

[0252] Preferably, the support 900 to be transported is a cobalt-chromium alloy support.

[0253] In Example 7, the cross-braiding of metal wires into a tubular structure can, for example, include any one of the following: one-up-one-down braiding, two-up-two-down braiding, double-strand composite braiding, or three-strand composite braiding.

[0254] In other embodiments, the stent delivery device includes a proximal push guide wire 110 and a plurality of sequentially connected distal wire braided structures 130.

[0255] In other embodiments, the distal flexible portion 130 may omit the distal non-transmissible spiral coil 132.

[0256] Example 8

[0257] As shown in Figure 16 (Figure 16 is a structural schematic diagram of the support system provided in Embodiment 8), a support system includes:

[0258] The stent delivery device includes a proximal push guide wire 110 and a distal engraved hollow structure 140. The distal engraved hollow structure 140 is disposed at the distal end of the proximal push guide wire 110. The distal engraved hollow structure 140 is laser-engraved into a hollow structure from a metal tube, then bound at both ends, and then heat-set into a structure with a large internal space in the middle and tightened 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).

[0259] The support 900 to be transported (nominal diameter of 3.5mm) is pressed onto the distal engraved hollow structure 140, and in the transport state, the distal end of the distal engraved hollow structure 140 is located 3.0mm away from the distal end of the support 900 to be transported; the support 900 to be transported is a distal open-loop support.

[0260] Preferably, the support 900 to be transported is a cobalt-chromium alloy support.

[0261] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A support conveying device, characterized in that, The conveying direction of the bracket is axial, the axial center is defined as the axis direction, and the intersection of the axis direction and any cross section perpendicular to the axis direction is the axis center point of the cross section. The support conveying device includes a force-functional component disposed at the distal end for reducing the passive force acting on the distal end of the support conveying device along the axial direction. The passive force is a reaction force generated when the distal end of the support conveying device abuts against an obstacle and transmitted from the distal end to the proximal end along the axial direction. The force-functional component is designed to have a structure that decomposes and / or redirects the passive force. The distance between the distal end of the force-function component and the distal end of the support conveying device as a whole is less than or equal to the nominal diameter of the support conveyed by the support conveying device.

2. The support conveying device as described in claim 1, characterized in that, The support conveying device includes a force transmission network centered on the axis point at the distal end, used to decompose the force applied at the axis point along the force transmission network; the force functional component is the force transmission network. The force transmission network converges at the far end near the axis point to form a far end center; The force transmission direction of the force transmission network is closer to the axial direction and towards the proximal end when subjected to radial restraint; When the force transmission network is not restrained by external force, it deforms, causing the force transmission direction of the force transmission network to deviate further from the axis direction and move towards the proximal side.

3. The support conveying device as described in claim 2, characterized in that, The force transmission network includes at least one circular array of lines arranged near the axis; the distal ends of the array lines of the circular array converge at the axis. Preferably, when the force transmission network is not constrained by external force, the angle between the force transmission direction at the distal end and the axial direction is 0~80°, excluding 0°, and preferably 1~30°.

4. The support conveying device as described in claim 2, characterized in that, The force transmission network is formed by connecting elastic pillars or by overlapping elastic threads; Preferably, the material of the force transmission network is a superelastic material and / or a shape memory material, preferably a nickel-titanium alloy; Preferably, the elastic support connection is formed by laser engraving, chemical etching or electrical discharge machining; Preferably, the size of the elastic support is 0.03~0.1mm; Preferably, the elastic threads are overlapped by weaving; Preferably, the size of the elastic thread is 0.001~0.1mm.

5. The support conveying device as described in claim 2, characterized in that, The force transmission network converges near the axis point to form a converging end. The converging end can be formed by any one or a combination of at least two of the following methods: convergence, welding, bonding, and integral molding. Preferably, the convergence is achieved by bringing the distal end of the force transmission network into a convergence component; Preferably, the convergence component includes a rigid convergence component and / or a flexible convergence component, with a flexible convergence component being more preferred; Preferably, the rigid convergence component includes a rigid ring, and more preferably, the rigid ring is made of a non-transparent material; Preferably, the flexible convergence component includes a flexible ring and a spiral winding structure, preferably a spiral coil.

6. The support conveying device as described in claim 5, characterized in that, The length of the converging end is less than or equal to the nominal diameter of the support conveyed by the support conveying device; Preferably, the ratio of the length of the converging end to the length of the force transmission network under constrained state is 0:1 to 0.8:1, excluding 0:1, and preferably 0.1:1 to 0.6:

1.

7. The support conveying device as described in claim 5, characterized in that, The distal end of the converging end has a convex curved surface; Preferably, a buffer end is provided at the distal end of the converging end, and the Shore hardness D of the buffer end is 50~80; Preferably, the material of the buffer end is a biocompatible polymer adhesive or solder paste, and more preferably includes UV-curable adhesive, epoxy resin adhesive or other polymer adhesives.

8. The support conveying device as described in claim 2, characterized in that, The force transmission network includes at least one circular array of lines arranged near the axis; the array lines of the circular array converge at the axis at their distal ends; the extension of the array lines toward the proximal ends is either regularly arranged or irregularly arranged. Preferably, the force transmission network converges into a proximal convergence portion at its proximal end; Preferably, the proximal convergence portion is positioned along the axial direction.

9. The support conveying device as described in claim 2, characterized in that, The support delivery device further includes a pushing component connected to the proximal end of the force transmission network; Preferably, the pushing component includes any one or a combination of at least two of the following: a pushing guide wire and an axially extending deformable component; Preferably, the axially extending deformable component includes any one or a combination of at least two of the following: a segmented expansion component and a helical wire structure.

10. The support conveying device as claimed in claim 1, characterized in that, The support conveying device includes: Axially extending push rod; A force buffer component is disposed at the distal end of the push rod; the force buffer component includes at least one force transmission member, the force transmission member forming a non-zero angle with the axial center line of the push rod; the distance between the distal end of the force buffer component and the distal end of the bracket conveying device as a whole is less than or equal to the nominal diameter of the bracket conveyed by the bracket conveying device. The force buffer component is configured such that when the axial thrust applied to the proximal end of the push rod causes the proximal end of the support conveying device to move axially by no more than half the axial length of the force transmission component, the force transmission component absorbs thrust fluctuations through elastic deformation; the force functional component is the force buffer component and / or the force transmission component. Preferably, the force buffer component has a guide portion at its distal end.

11. The support conveying device as described in claim 10, characterized in that, The structure of the force buffer component includes any one of the following: lantern-shaped mesh structure, spiral structure, and wave-shaped structure. Preferably, in an unrestrained state, the angle between the distal end of the force transmission member extending from its starting point and the axial centerline is 5 to 70°. Preferably, the force transmission component is made of a filamentous material with an elastic modulus of 30~180 GPa, and is preferably any one or a combination of at least two of the following: hyperelastic material and shape memory material; Preferably, when the axial thrust applied to the proximal end of the push rod causes the proximal end of the support conveying device to move axially by no more than half the axial length of the force transmission member, the axial thrust fluctuation at the distal end of the support conveying device is kept within ≤50mN.

12. The support conveying device as described in claim 11, characterized in that, The lantern-shaped mesh structure is obtained by weaving multiple elastic threads into a hollowed-out tube network structure and then pre-forming it into a structure where the two ends converge and the middle cavity is hollow, wherein the elastic threads are force transmission components; or, the lantern-shaped mesh structure is obtained by extending at least two elastic threads side by side and pre-forming them into a structure where the two ends converge and the middle cavity is hollow, wherein the elastic threads are force transmission components. Preferably, the guide portion and the converging end of the force transmission component are designed as an integral part; Preferably, the force transmission components are distributed along the meridian direction on the surface of the lantern-shaped structure, or extended at an angle to the meridian direction.

13. The support conveying device as described in claim 11, characterized in that, The lantern-shaped mesh structure is obtained by carving metal tubes into a hollow mesh structure and then pre-forming it into a structure where the two ends converge and the middle cavity is hollow. The support columns of the hollow mesh structure are connected end to end to form a force transmission component. Preferably, the guide portion and the converging end of the force transmission component are designed as an integral part; Preferably, the hollowed-out mesh frame is prepared by laser engraving and / or chemical etching.

14. The support conveying device as described in claim 11, characterized in that, The force buffer component is an elastic structure pre-formed into a spiral and / or wave-like structure, and the guide portion extends axially. Preferably, the spiral structure and / or wavy structure are obtained through a predetermined process.

15. The support conveying device as described in claim 11, characterized in that, The length of the guide portion is less than or equal to the nominal diameter of the support conveyed by the support conveying device; Preferably, the guide portion is sleeved on the distal end of the force buffer component; Preferably, the guide portion includes a rigid ring and / or a flexible ring; Preferably, the rigid ring is a non-transparent ring; Preferably, the flexible ring is a flexible single ring with a spiral winding structure, and more preferably a spiral coil; Preferably, the guide portion is made of a non-transparent material.

16. The support conveying device as described in claim 11, characterized in that, The guide portion is provided with a buffer end at its distal end. The buffer end has a Shore hardness D of 50 to 80 and a tensile strength of 2% to 150%.

17. A support system, characterized in that, The support system includes: The support conveying device according to any one of claims 1 to 16; The support is mounted at the distal end or near the distal end of the support delivery device according to any one of claims 1 to 16.

18. The support system as claimed in claim 17, characterized in that, The bracket is sleeved on the bracket conveying device according to any one of claims 1 to 16 in the conveying state, and the distal end of the bracket is disposed outside the force function component. Preferably, in the conveying state, the distal end of the bracket is located on the outside near the distal end of the force-function component.

19. The support system as claimed in claim 17, characterized in that, The position extending axially a predetermined distance from the distal end of the support is defined as the extreme position, and the distal end of the support delivery device is located on the proximal side of the extreme position; the predetermined distance is 0.8 to 1 times the nominal diameter of the support; Preferably, with the far end of the support to be transported as the 0 point, the far end of the support transport device is located within the range of -5mm to + the nominal diameter of the support to be transported. Optionally, the distal end of the support to be transported is an open-loop structure, with the distal end of the support to be transported as the 0 point, and the distal end of the support transport device is located within the range of 0~+5mm from the distal end of the support to be transported. Optionally, the distal end of the support to be transported is a closed-loop structure, with the distal end of the support to be transported as the 0 point, and the distal end of the support transport device is located within the range of -5mm to +5mm of the distal end of the support to be transported. Preferably, with the far end of the support to be transported as the zero point, the far end of the support transport device is located near the far end of the support to be transported, and the support to be transported is a support with a closed loop at the far end; the support to be transported is preferably a cobalt-chromium alloy support.

20. The support system as claimed in claim 19, characterized in that, The elastic modulus of the material at the distal end of the support conveying device is less than that of the material at the proximal end of the support conveying device. Preferably, the distal end of the support delivery device includes a structure made of a non-transparent material.

21. The support system as claimed in claim 17, characterized in that, include: Self-expanding stent; catheter; The stent delivery device as described in any one of claims 10 to 16 is disposed within the conduit and extends axially, wherein the stent is loaded at its distal end and the proximal end is used to receive the pushing force and transmit the pushing force to the distal end; the distal end of the stent is defined as point X. On the stent delivery device, a force change point A is provided at a predetermined axial distance from the proximal side of point X; a force buffer component is provided at the distal side of the force change point A, so that after the force change point A of the stent delivery device extends beyond the distal end of the catheter, the pushing force fluctuation range transmitted to the distal end is ≤50mN within a range of no more than 1.5mm of the proximal end advancement displacement of the stent delivery device; the predetermined distance is ≥1.5mm; Preferably, the axial length of the force transmission component is ≥3.0mm.

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