Stent device

Abstract

To provide a stent device.SOLUTION: A stent device comprises a sleeve. The sleeve is formed with a plurality of compactable spring ring elements (21) arranged along its length, and has a compacted state and an expanded state. Each of the ring elements has an undulating profile at the surface of the sleeve so that adjacent ring elements at least partially overlap along the longitudinal extent of the device. The ring elements are compactable against natural resilience of the ring elements to reduce the outer diameter of the sleeve for making it possible to house the compacted stent device in a frangible sheath. Adjacent ring elements are inter-coupled to substantially maintain their axial spacing between the compacted and expanded states.SELECTED DRAWING: Figure 2A

Description

Technical Field

[0001] The present invention relates to a stent device.

Background Art

[0002] In relation to this, current treatment methods for aortic dissection and aneurysm mainly utilize conventional surgical grafts and open surgery. Endovascular treatment is also possible. However, it is complicated to maintain perfusion to all major branch vessels that radially extend from the top of the aortic arch purely by an endovascular approach. Therefore, endovascular treatment is currently very limited.

[0003] Furthermore, when using a conventional surgical graft, often a full thoracotomy, i.e., a large surgical opening of the chest cavity, is required. This typically requires coronary artery bypass surgery and also requires inducing hypothermia and cardiac arrest. Performing such surgical procedures is not without the risk of further complications.

[0004] Furthermore, known intravascular stent devices and their delivery systems rely on the use of an internal delivery support shaft, which typically features a tip integrally molded at its end to facilitate insertion, and also includes a mounting loop and release wire for supporting and deploying the stent device. In this type of device, the stent device can be suspended from the delivery system by its tip end. It remains there until withdrawal from the sheath is complete. It can then be released from the delivery system. Typically, after release by the release wire, the supporting internal central shaft and tip assembly must then be completely removed from inside the stent device by pulling these items through the inside of the device lumen. These items must be removed carefully to overcome the potential risk of unintentionally snagging and dislodging the previously deployed device. To provide this function, the delivery system typically requires other auxiliary elements, such as a guidewire passing through the internal lumen of the shaft and the tip molded part.

[0005] With such components, even if necessary, it is not possible to anastomose the non-stented end of the device to either an auxiliary device or the primary blood vessel before deploying the stented portion. [Overview of the project] [Problems that the invention aims to solve]

[0006] The object of the present invention is to provide an improved stent device that can mitigate the problems associated with currently available devices.

[0007] The present invention provides a stent device comprising a sleeve. The sleeve is formed of a plurality of compressible spring ring elements arranged along its length, having a compressed state and an expanded state. Each ring element has a wavy profile on the surface of the sleeve such that adjacent ring elements overlap at least partially along the longitudinal range of the device. The ring elements are compressible against the natural elasticity of the ring elements, reducing the outer diameter of the sleeve to allow the compressed stent device to be housed in a frangable sheath. Adjacent ring elements are interconnected such that they substantially maintain an axial spacing between the compressed and expanded states.

[0008] In this way, the stent device can be compressed to reduce its diameter for insertion. The sleeve is in a compressed, constrained state when housed within such a flangable sheath. When released from the sheath, the sleeve expands to a larger diameter through the ring element.

[0009] By providing a stent device in a compressible form, a unified column rigidity is achieved. This eliminates the need for an internal delivery mechanism to deploy the stent device. This simplifies the stent deployment process. Importantly, this avoids the risks associated with procedures to extract such internal delivery mechanisms, particularly the dislodgement of the newly inserted stent device. The externalization of stent device deployment enabled by the present invention further enhances the ability of the stent device to anastomose with other auxiliary devices or the primary blood vessel.

[0010] Preferably, the wavy profile of each ring element extends around the surface of the sleeve on its outer circumference. Different wavy ring element profiles, such as a "Z" shape, may be used. However, each ring element preferably has a hyperbolic parabolic profile, thereby being substantially saddle-shaped. In this way, in the compressed configuration, the ring elements can overlap in a scaly manner. Thus, in the overlapping configuration, the ring elements are stacked axially along the length of the sleeve. The overlapping nature of the ring elements in the compressed configuration facilitates the provision of column stiffness, which is easier to use in a developing device. In this respect, in the compressed configuration, the peaks of one ring element overlap the valleys of adjacent ring elements. In this way, in the compressed configuration, the close contact of portions of adjacent ring elements provides column stiffness to the device.

[0011] Preferably, the ring elements are arranged such that adjacent ring elements are mounted along the sleeve to maintain their relative ring positions. In this way, the ring positions are maintained across the compressed and uncompressed states of the stent device.

[0012] Conveniently, the ring elements are interconnected by being attached to the sleeve material. Preferably, in the portions where adjacent ring elements overlap axially, the circumferential spacing between them is less than or equal to the maximum change in the axial spread of each ring element when transitioning from an expanded configuration to a compressed configuration when the device is in an open configuration. Thus, when in a compressed state, tension is applied to the fabric between adjacent ring elements, preventing adjacent rings from colliding with each other axially.

[0013] Conveniently, the sleeve material is a fabric such as gel-coated polyester.

[0014] Preferably, the ring element is formed from nitinol wire. Conveniently, the wire has a diameter in the range of 0.08 to 0.24 mm.

[0015] Furthermore, the stent device may be equipped with a soft tip at its proximal end. In this regard, if the device is housed in a sheath, the soft tip may extend beyond the end of the sheath. The soft tip enhances the functionality of the stent device and provides a non-traumatic characteristic, allowing the stent device to be deployed without an internal delivery shaft, as is the case with known devices.

[0016] Thus, a portion of the proximal end of the stent device may be exposed and covered with one or more soft sutures or PTFE threads to form a non-traumatic tip. In this regard, the soft tip can be formed from the stent material at the end of the device. It may include heavy sutures on the saddle profile. Furthermore, it may be at the proximal end of the stent device The ring elements may be provided with one or more additional layers of sutures.

[0017] A further aspect of the present invention provides a stent device comprising a sleeve formed of a plurality of compressible spring ring elements arranged along its length. A soft end tip is formed at the proximal end of the sleeve. The soft end tip comprises a portion of the sleeve covered with one or more soft suture materials or PTFE threads.

[0018] In this regard, the soft end tip may be formed from stent material at the end of the device, folded into a ring shape, and held in place with sutures.

[0019] A soft-end tip may have heavy sutures on a ring element with a saddle profile. Furthermore, it may have one or more additional layers of sutures on one or more ring elements at the proximal end of the sleeve. The saddle or hyperbolic parabolic profile of the ring element naturally gives the soft tip a rounded shape, optimizing its non-traumatic properties.

[0020] Embodiments of the present invention are described by examples and with reference to the following drawings.

Brief Description of the Drawings

[0021] [Figure 1] It is a cross-sectional view of a compatibility deployment device in which the stent device with sheath of the present invention is disposed therein. [Figure 2A] It is a view showing the stent device of the present invention. [Figure 2B] It is a view showing the stent device of the present invention. [Figure 3] It is a schematic view showing adjacent ring elements of the stent device of the present invention.

Modes for Carrying Out the Invention

[0022] In this regard, FIG. 1 shows a cross-sectional view of the stent device of the present invention and a compatible deployment device 1. The deployment device includes a body 2 in which the sheath-equipped stent device 3 of the present invention is disposed.

[0023] In this regard, the body includes a bore 4. The bore 4 is dimensioned such that the sheath-equipped stent device 3 can be positioned within the bore, but not so tightly as to prevent the sheath material from moving relative to the bore and the stent device.

[0024] Regarding the stent device, as shown in FIGS. 2a and 2b without and with a sheath respectively, this preferably comprises a lumen or sleeve 20 made of a typically gel-coated polyester fabric and equipped with a series of springs such as "stent elements", typically a wavy "Z" - shaped stent, or in a preferred embodiment, a saddle ring, i.e., a ring element 21 formed from a nitinol wire in the shape of a hyperbolic paraboloid.

[0025] The plurality of ring elements 21 are arranged along the axis of the lumen. These are circumferentially attached to the fabric by sutures and form the stent mounting device portion. The stent mounting device portion has the ability to be constrained within a tube of significantly small diameter, i.e., the sheath 40.

[0026] As shown in Fig. 2b, when compressed within the small-diameter sheath 40, a stent device with a sheath (having a suitably selected oversize) can be easily inserted into the lumen of the branched blood vessel. When the sheath is removed from the stent device, the stent mounting portion radially expands outwardly to enable deployment of the stent device within the native blood vessel. The radially expanding stent elements contact and press against the blood vessel inner wall, forming a non-sewn sealed joint that fits snugly.

[0027] The overlapping nature of the ring elements in the compressed configuration provides a sleeve having column rigidity that facilitates use in a conforming deployment device as shown in Fig. 1.

[0028] More specifically, by providing the stent device in a radially compressible form, integral column rigidity is obtained. Thereby, an internal delivery mechanism for deploying the stent device can be made unnecessary. This simplifies the stent deployment process. Also importantly, this can avoid the risks associated with the procedure of withdrawing such an internal delivery mechanism, particularly the dislodgment of the newly inserted stent device.

[0029] In this regard, the ring elements are preferably arranged within the sleeve such that the axial spacing of adjacent elements is maintained. In this way, the position of the ring elements is maintained across the compressed and deployed states of the stent device.

[0030] As shown in Fig. 3, the ring element 21 has adjacent ring elements axially DuplicateIn this configuration, the circumferential spacing a-b between the ring elements is connected to the sleeve material such that the circumferential spacing a-b is less than or equal to the maximum change dL in the axial spread of each ring element when transitioning from an expanded configuration to a compressed configuration when the device is in an open configuration. Therefore, when in a compressed state, tension is applied to the fabric between adjacent ring elements, preventing adjacent rings from colliding with each other axially.

[0031] In this regard, the device can be configured with a relatively high saddle height, i.e., a relatively large axial difference between the peaks and valleys of the rings. Furthermore, preferably, the ring spacing is made smaller than the saddle height, so that the peaks and valleys of adjacent rings overlap. This characteristic, in combination with adjacent portions of the supported fabric, is used to maintain the position of the stent device relative to the body 2 before and during the process of removing it from the sheath.

[0032] As shown in Figure 1, a portion of a stretchable, crimped fabric 15, typically made of gel-coated polyester, can be provided at or near the distal end of the stent placement area. This portion is joined and attached by sutures to form a blood-tight, continuous lumen of the endoprosthesis. In some embodiments, this portion may also include a "Y" shaped branched lumen. without The attachment area is designed to allow the endoprosthesis to be joined by suturing it to either the prosthesis body or, alternatively, to a healthy portion of the original blood vessel, thereby restoring blood flow to the original branch vessels.

[0033] Preferably, the sheath is a thin wall (typically made of PTFE material) with a pre-positioned location for linear fracture without requiring additional grooves or perforations. The sheath may comprise three parts: a proximal circular portion slightly longer than the length of the compressed stent-implanted portion, a tail portion at its distal end, and an intermediate portion where the circular portion splits and propagates into two tail elements.

[0034] In the adaptability deployment device shown in Figure 1, these flat, ribbon-shaped tail elements 7 originate from the ends of the circular section and can be formed by folding. The formed tails are fed through or via the restriction 5 within the body 2 of the adaptability deployment device to individual strap elements. There, they can be tied together to remove the sheath. It can form a single user interface.

[0035] As shown in Figure 1, the restriction 5 within the bore 2 is configured to obstruct the movement of the stent device. However, this restriction allows the stent device sheath material, i.e., the tail 7, to pass through this restriction for access at the distal end of the body 2.

[0036] Any suitable means can be employed to allow the sheath material to pass through the restriction. However, the adaptability deployment device has two arc-shaped openings 13 facing the restriction 5. The openings extend longitudinally in the axial direction of the body. The openings are substantially circumferential and form an angle of 90 to 120 degrees. In this regard, each opening provides a passage for the tail of the sheath material 7. The sheath material is divided at point 9 in the bore 4.

[0037] The main body is the crimp structure of the stent device. fabric The device is equipped with a side window 10 that allows a sheathed stent device to be placed inside the main body with 15 protruding laterally from the main body through the window. without Attachment It is a part The fabric 15 provides a path for passing out of the body 2 substantially perpendicular to the axis of the sheathed sheath within the bore, allowing access to the distal end of the stent device. This end can then be trimmed to a length that matches the individual patient's anatomical structure, facilitating suturing to an auxiliary graft or the original blood vessel.

[0038] Once the stent device is fully deployed, it can be removed from the main body 2 of the adaptation device.

[0039] In the above-described compatibility deployment device, the main body 2 holds and supports the sheathed stent device 3, allowing the proximal compressed portion to be inserted into either the primary blood vessel or the auxiliary stent device body. As a result, it can be held for subsequent withdrawal from the sheath and deployment, and then perfusion to the blood vessel can be resumed.

[0040] This simplifies the delivery system in terms of its complexity. As a result, the number of components is reduced, the number of procedural steps and potential risks for the user are decreased, and a more time-efficient and simplified device deployment becomes possible.

[0041] The internal arrangement within the device allows the splitting of the sheath to be controlled when the user pulls the strap element. As the sheath is pulled beyond the internal borestriction, the circular lumen surface of the sheath continues to split, propagating along the two tail elements 7. Simultaneously, the movement applied to the strap is transmitted to the proximal end of the sheath, causing it to slide over the stent device, allowing the compressed stent device to be released from its radial constraints. In doing so, the stent device opens and engages with the lumen of the blood vessel.

[0042] As shown in Figures 1, 2a, and 2b, the stent may have the features of an integrated stent device tip 24. This can be provided at the proximal end of the stent placement area of ​​the stent device 3. When compressed within the constraints of the sheath, it is capable of protruding beyond the end of the sheath, partially exposing the compressed stent device element covered with soft sutures (or PTFE sutures) to provide a non-traumatic tip-like feature.

Claims

1. A stent deployment device, The main body, A bore defined within the main body, A restrictor placed within the bore, The restriction comprises at least one opening extending in the longitudinal direction, A window located inside the side of the main body and The main body having, A sheath extending along the length of the main body, A stent device having a proximal end and a distal end that define the stent axis, wherein the stent device is disposed within the bore of the main body, A fabric sleeve having a plurality of compressible spring ring elements arranged along its length, wherein the sleeve has a compressed state and an expanded state, Each of the ring elements has a wavy profile on the surface of the sleeve such that it overlaps axially along the length of the sleeve in a configuration in which adjacent ring elements are compressed. The ring element is compressible against the natural elasticity of the ring element, and the outer diameter of the sleeve is reduced in order to allow the compressed stent device to be compressed within the sheath. The stent device has adjacent ring elements that are interconnected such that they substantially maintain longitudinal and axial spacing between the compressed state and the expanded state. The sheath is positioned to cover at least a portion of the stent device, the restriction being configured to obstruct the movement of the stent device and allow passage through the sheath, and at least a portion of the fabric passing through the window in the side of the body and exiting the body perpendicular to the stent axis, and the sheath A stent deployment device equipped with [a specific feature].

2. The stent deployment device according to claim 1, wherein the at least one opening has a shape that is circumferential to the restriction.

3. The stent deployment device according to claim 1, wherein the sheath is configured to be divided within the bore.

4. The stent deployment device according to claim 3, wherein the at least one opening provides a passage for the tail of the sheath material.

5. The wavy profile of each ring element extends around the outer circumference of the sleeve and around the surface of the sleeve, according to claim 1.

6. The stent deployment device according to claim 1, wherein each ring element has a hyperbolic paraboloid profile.

7. The stent deployment device according to claim 1, wherein, in a compressed configuration, multiple peaks of one ring element axially penetrate multiple valleys of axially adjacent ring elements along the length of the sleeve.

8. The stent deployment device according to claim 1, wherein the ring elements are interconnected by being attached to the material of the sleeve.

9. The stent deployment device according to claim 1, wherein, in the portion where adjacent ring elements overlap in the axial direction, the ring elements are interconnected such that the circumferential spacing between the adjacent ring elements is less than or equal to the displacement in the axial spreading of the ring elements when transitioning from an expanded configuration to a compressed configuration.

10. The stent deployment device according to claim 1, wherein the ring element is formed from a nitinol wire and has a diameter in the range of 0.08 to 0.24 mm.

11. A stent deployment device according to claim 1, comprising a tip covered with suture or PTFE thread at its proximal end, wherein, when the compressed device is housed in a sheath, the tip extends beyond the end of the sheath.

12. The stent deployment device according to claim 11, wherein the tip is formed at the proximal end of the sleeve from a plurality of sutures in one or more ring elements.

13. The stent deployment device according to claim 1, wherein the ring element has an arc-shaped profile.

14. The stent deployment device according to claim 1, wherein the ring element comprises a saddle profile.

15. The stent deployment device according to claim 1, further comprising a non-stent portion at its distal end.

16. The stent deployment device according to claim 15, wherein the non-stent portion has a fabric with an elastic crimped structure.

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