Delivery device and delivery system for delivering a stent

Abstract

This invention provides a delivery device and system for delivering stents. The delivery device includes a sheath for receiving the stent and a support member slidably disposed within the sheath. The support member includes a pushing portion and a plurality of supporting portions disposed within the pushing portion, wherein the distal ends of at least two supporting portions are not flush with each other, so that the proximal end of the stent can be released from the support member in stages. The delivery device of this invention can effectively prevent the proximal end of the vascular stent from simultaneously springing outwards at the same moment during release, thus avoiding further damage to the surrounding vascular wall.

Description

Technical Field

[0001] This invention relates to the field of medical devices, and more specifically to a delivery device and delivery system for delivering stents. Background Technology

[0002] Aortic diseases mainly include true aortic aneurysms, pseudoaneurysms, and dissecting aortic aneurysms. Currently, the main treatments for aortic diseases are surgical intervention and endovascular interventional therapy. Surgical intervention, also known as open surgery, involves thoracotomy or laparotomy depending on the location of the lesion. Surgical intervention is highly invasive and has a slow recovery time, posing a significant challenge for elderly, frail, or patients who cannot tolerate major surgery. Compared to surgical intervention, endovascular interventional therapy offers advantages such as minimal invasiveness, high safety, and rapid postoperative recovery, leading to its increasingly widespread application and rapid development.

[0003] The procedure of endovascular interventional therapy mainly includes: loading a vascular stent into the delivery sheath of the delivery device; establishing a surgical channel using a guidewire; allowing the delivery sheath to travel along the guidewire through the iliac artery, abdominal aorta, thoracic aorta, aortic arch, ascending aorta, or aortic valve to reach the designated lesion location; releasing the vascular stent; and after self-expansion, the vascular stent adheres tightly to the vessel wall, isolating the lesion location of the aneurysm, eliminating the impact of blood flow on the vessel wall at the lesion location, restoring the correct direction of blood flow, thereby achieving the therapeutic effect.

[0004] During stent deployment, blood flow within the blood vessel continues. With each heartbeat, the blood flow rhythmically impacts the deploying stent, resulting in high pressure and strong impact. To prevent or minimize stent displacement due to blood flow during deployment, the proximal end of the stent is often detachably and securely connected to the guide head of the delivery device. After the distal segment of the stent is deployed, the proximal end is then released, thus completely dispersing the stent.

[0005] However, the existing delivery device has a drawback: when the vascular stent is released, the proximal end of the stent will simultaneously spring outwards in an instant, increasing the risk of further damage to the physiological tissues around the stent. For example, the proximal end of the stent, which springs outwards in an instant, will compress the surrounding vascular wall, causing further damage to the vascular wall. Summary of the Invention

[0006] In view of this, in order to solve the problem that the proximal end of the vascular stent will bounce outward at the same time during release, causing further damage to the surrounding vascular wall, the present invention provides a delivery device and delivery system.

[0007] This invention is achieved through the following technical solutions:

[0008] A delivery device for delivering a stent includes a sheath for receiving the stent and a support slidably disposed within the sheath. The support includes a pushing portion and a plurality of supporting portions disposed in the pushing portion, wherein the distal ends of at least two supporting portions are not flush with each other, so that the proximal end of the stent can be released from the support in stages.

[0009] In some embodiments, a plurality of the support portions are distributed at circumferential intervals along the push portion.

[0010] In some embodiments, the support member includes 2 to 10 of the support portions.

[0011] In some embodiments, the support member includes 4 to 7 of the support portions.

[0012] In some embodiments, the support is constructed as a cylindrical, semi-cylindrical, or other irregularly shaped pillar.

[0013] In some embodiments, the pushing part includes a pushing tube and a fixing seat disposed on the pushing tube, and a plurality of the supporting parts are disposed on the fixing seat.

[0014] In some embodiments, the fixing base includes a connecting pipe disposed on the push tube and a fixing block disposed on the connecting pipe, and a plurality of the supporting parts are disposed on the fixing block.

[0015] In some embodiments, the plurality of support portions are distributed at intervals along the circumference of the fixing block.

[0016] In some embodiments, the conveying device further includes a core tube passing through the support member and a guide head disposed on the core tube, the guide head being located at the distal end of the support member, and the pushing portion being slidably sleeved on the core tube.

[0017] In some embodiments, the guide head is provided with a plurality of clearance holes, and the plurality of clearance holes includes at least one insertion hole capable of being inserted into one of the support portions.

[0018] In some embodiments, the clearance hole is located on the proximal end face of the guide head, and the clearance hole extends axially from the proximal end face of the guide head toward the distal end of the guide head.

[0019] In some embodiments, the delivery device further includes a fixing portion for connecting the core tube and the guide head. The proximal end face of the guide head has a protrusion that protrudes from the proximal end face of the guide head toward the proximal end of the delivery device. The outer diameter of the protrusion is smaller than the outer diameter of the proximal end face of the guide head, such that the proximal end face of the guide head forms a stepped surface. The clearance hole is located on the stepped surface. The protrusion is located at the distal end of the fixing portion, and there is a gap between the protrusion and the fixing portion, which forms an annular groove for receiving the proximal end of the support.

[0020] On the other hand, the present invention also provides a conveying system including the aforementioned conveying device and the bracket housed within the sheath, the bracket including a plurality of connecting portions, the plurality of connecting portions of the bracket being releasably connected to corresponding support portions.

[0021] In some embodiments, a support tube is provided between the support member and the sheath, and a gap is provided between the distal end of the support tube and the proximal end of the support member, the gap forming an annular space for accommodating the stent, and the distal end of the support tube is used to contact the distal end of the stent to support the stent.

[0022] During the procedure, when the stent is released by sliding the support of the delivery device provided by the present invention, each connection of the stent can be released from the corresponding support in stages, rather than being released outwards all at once. That is, at least a part of the stent is released first, and then the other part is released, thereby reducing the risk of further damage to the blood vessel wall around the stent. Attached Figure Description

[0023] Figure 1 A schematic diagram of the delivery system structure after partial cross-section of the sheath according to an embodiment of the present invention is shown;

[0024] Figure 2 It shows Figure 1 A schematic diagram of the vascular stent structure of the delivery system shown;

[0025] Figure 3 It shows Figure 1 A schematic diagram showing the positional relationships of the various components of the conveying device in the conveying system shown.

[0026] Figure 4 It shows Figure 3 A schematic diagram of the structure of the conveying device after the support component is concealed behind the push tube;

[0027] Figure 5 A schematic diagram of the support portion of the conveying device according to another embodiment of the present invention is shown;

[0028] Figure 6 The present invention is shown. Figure 3A schematic diagram showing the positional relationship between the guide head, protrusion, core tube, and push tube of the conveying device.

[0029] Figure 7 The partial connection of the vascular stent is shown. Figure 3 A partial schematic diagram of the release of the support member of the conveying device shown;

[0030] Figure 8 The connection points of the vascular stents are shown to be attached to... Figure 3 A schematic diagram of the support portion of the conveying device shown;

[0031] Figure 9 The partial connection of the vascular stent is shown. Figure 3 A schematic diagram of the structure for releasing the support member of the conveying device shown.

[0032] Figure Labels

[0033] 10. Delivery device; 20. Vascular stent; 201. Main body section; 202. Connecting section; 2021. Connecting part; 203. Covering membrane; 204. Metal ring; 30. Sheath; 40. Annular space; 41. Support; 50. Pushing part; 501. Push tube; 502. Fixing seat; 5021. Connecting tube; 5022. Fixing block; 60. Support part; 601. First support part; 602. Second support part; 70. Support tube; 80. Core tube; 90. Guide head; 100. Clearance hole; 1001. Insertion hole; 110. Protrusion; 120. Stepped surface; 130. Fixing part; 140. Annular groove. Detailed Implementation

[0034] The present invention will now be described in detail with reference to the accompanying drawings and specific embodiments, so that the technical solution and beneficial effects of the present invention will be clearer. It should be understood that the accompanying drawings are provided for reference and illustration only, and are not intended to limit the present invention. The dimensions shown in the accompanying drawings are only for the purpose of clear description and are not intended to limit the scale relationship.

[0035] It's important to clarify beforehand that in endovascular interventional therapy, the end of the delivery device closer to the operator is typically defined as the proximal end, and the end farther from the operator is defined as the distal end. For vascular stents, the end closer to the heart is defined as the proximal end, and the end farther from the heart is defined as the distal end. A peak refers to the highest point formed by two curves in a sine wave, similar to an "n" shape, while a trough refers to the lowest point formed by two curves in a sine wave, similar to a "v" shape.

[0036] refer to Figure 1An embodiment of the present invention provides a conveying system including a conveying device 10 and a support 20 housed within the conveying device 10. The conveying device 10 includes a sheath 30 and a support 41 slidably housed within the sheath 30. The sheath 30 and the support 41 together enclose an annular space 40 for housing the support 20. The support 41 is used to releasably connect the support 20.

[0037] For ease of explanation, this embodiment uses... Figure 2 The vascular stent 20 shown is illustrated as an example. The vascular stent 20 includes an expandable structure and a compressible structure. In the expandable structure, the vascular stent 20 includes a hollow cylindrical main body segment 201 and an annular connecting segment 202 fixedly connected to one end of the main body segment 201. The main body segment 201 is provided with a covering 203, while the connecting segment 202 is not covered. The main body segment 201 can be formed by stitching multiple shape-memory metal rings 204 to the covering 203. The metal rings 204 can also be disposed on the covering 203 by means of lamination, stamping, attaching, inlaying, or hot pressing, without limitation. The coating 203 can be made of one or more of PU, PET, PTFE, e-PTFE, or other polymer materials. The metal ring 204 and the connecting section 202 can be made of one or more of nickel-titanium alloy, nickel-titanium superelastic alloy, cobalt-chromium-nickel-molybdenum alloy, copper-based shape memory alloy, iron-based shape memory alloy, medical stainless steel alloy, or various polymers (e.g., polynorbornene, polyurethane, polylactic acid copolymer, etc.), which are not limited herein. The connecting section 202 includes multiple connecting portions 2021 for connecting with the support member 41 of the delivery device 10. In this embodiment, the connecting portion 2021 can be an n-shaped or V-shaped structure formed by bending elastic metal wires, and multiple connecting portions 2021 can be connected by stitching or weaving to form a connecting section 202 with crests and troughs; or the connecting section 202 can also be cut from a ring-shaped metal sheet, which is not limited. It is understood that in other embodiments, other types or structures of suitable supports can also be used.

[0038] refer to Figure 3 In this embodiment, the delivery device 10 further includes a core tube 80 passing through the support member 41 and a guide head 90 fixedly connected to the distal end of the core tube 80. The support member 41 is slidably arranged between the sheath 30 and the core tube 80. Preferably, a support tube 70 is slidably sleeved on the support member 41, the support tube 70 is located inside the sheath 30, and the distal end of the support tube 70 is used to contact the distal end of the vascular stent 20, serving to support the vascular stent 20. During the release process, the pushing action of the distal end of the support tube 70 on the distal end of the vascular stent 20 ensures the stability of the release process of the vascular stent 20. It is understood that in other embodiments, the support tube 70 may be omitted. Reference Figure 3 and Figure 4 In this embodiment, the support member 41 includes a pushing part 50 and a plurality of (i.e., no less than two) support parts 60 disposed at the distal end of the pushing part 50. The plurality of support parts 60 are used to releasably connect to the vascular stent 20. In particular, the distal ends of at least two of the plurality of support parts 60 are not flush with each other, so that when the support member 41 is slid during the operation to release the vascular stent 20, the proximal end of the vascular stent 20 can be released from the corresponding support part 60 in stages, avoiding the entire proximal end of the vascular stent 20 from popping outward at the same moment. That is, at least a part of the proximal end of the vascular stent 20 is released first, and the other part is released later, thereby reducing the risk of further damage to the surrounding physiological tissues by the vascular stent 20.

[0039] Preferably, the plurality of support portions 60 are distributed at intervals along the circumference of the push portion 50 to better accommodate each connecting portion 2021 of the stent in two adjacent support portions 60. More preferably, the plurality of support portions 60 are evenly distributed at intervals along the circumference of the push portion 50 to connect and release the vascular stent 20 more evenly and stably.

[0040] This embodiment illustrates the use of six support portions 60 in the support member 41, but the number of support portions 60 is not limited. It is understood that in other embodiments, the support member 41 may include other numbers of support portions 60. Preferably, the support member 41 includes 2 to 10 support portions 60, more preferably 4, 5, 6, or 7 support portions 60, and most preferably 6 support portions 60 as in this embodiment.

[0041] For ease of distinction, three of the support portions 60 are designated as first support portions 601, and the other three support portions 60 are designated as second support portions 602. The distal ends of the three first support portions 601 protrude beyond the distal ends of the three second support portions 602, and the first support portions 601 and second support portions 602 are arranged alternately along the circumference of the pushing portion 50. This arrangement ensures that when the connecting portions 2021 of the vascular stent 20 are released from the such distributed support portions 60, a portion of the connecting portions 2021 of the vascular stent 20 are released from the three second support portions 602 first, followed by another portion of the connecting portions 2021 of the vascular stent 20 from the three first support portions 601. This makes the entire release process of the vascular stent 20 more uniform and stable, and more effectively reduces or avoids the risk of multiple connecting portions 2021 of the vascular stent 20 simultaneously springing outward and causing further damage to surrounding physiological tissues.

[0042] Understandably, in other embodiments, the distal ends of each support portion 60 may not be flush with each other, as long as the step-by-step release of each connecting portion 2021 of the vascular stent 20 is ensured; for example, the distal end of at least one support portion 60 may protrude beyond the distal ends of other support portions 60; for example, the distal ends of at least two support portions 60 may protrude beyond the distal ends of other support portions 60, and the at least two support portions 60 may be arranged adjacently or spaced apart; for example, the distal ends of at least three support portions 60 may protrude beyond the distal ends of other support portions 60, and the at least three support portions 60 may be arranged adjacently or spaced apart; for example, the distal ends of at least four support portions 60 may protrude beyond the distal ends of other support portions 60, and the at least four support portions 60 may be arranged adjacently or spaced apart; for example, the distal ends of at least seven support portions 60 may protrude beyond the distal ends of other support portions 60, and the at least seven support portions 60 may be arranged adjacently or spaced apart, etc. This embodiment is only for illustrative purposes and does not limit the degree of protrusion between the distal ends of each support portion 60.

[0043] Preferably, the multiple support portions 60 are constructed as multiple solid cylindrical pillars, which provides a simple and stable structure. In other examples, the support portions 60 may also be formed as solid semi-cylinders or hollow semi-cylinders, without limitation. Figure 5 As shown, in some other examples, the support 60 may also take the form of a hollow semi-cylindrical shape formed by bending a sheet.

[0044] refer to Figure 3 and Figure 4 In this embodiment, the pushing part 50 includes a longitudinally elongated pushing tube 501 and a fixing seat 502 disposed on the pushing tube 501, and a plurality of support parts 60 disposed on the fixing seat 502. More specifically, the fixing seat 502 includes a connecting tube 5021 disposed on the pushing tube 501 and a fixing block 5022 disposed on the connecting tube 5021. The plurality of support parts 60 are spaced apart circumferentially along the fixing block 5022. The fixing block 5022 may be hollow hemispherical, conical, or other shapes. It is understood that in other embodiments, the pushing part 50 may also adopt other structures.

[0045] refer to Figure 6 and Figure 7Furthermore, in this embodiment, the guide head 90 is provided with at least one clearance hole 100, which includes at least one insertion hole 1001 capable of engaging with one of the support portions 60, thereby more stably confining the vascular stent 20 connected to the support portion 60 within the delivery device 10 and preventing the connection portion 2021 of the vascular stent 20 from sliding out of the support portion 60. The clearance hole 100 is located on the proximal end face of the guide head 90 and extends axially from the proximal end face of the guide head 90 toward the distal end of the guide head 90. It is understood that in other embodiments, the clearance hole 100 may also take other forms. For example, the clearance hole 100 may also be formed as a circular or square groove, etc. It is also understood that in other embodiments, the clearance hole 100 may be omitted.

[0046] In this embodiment, the number of insertion holes 1001 is the same as the number of support portions 60, and each support portion 60 corresponds to one insertion hole 1001 that can be inserted and engaged with it. It can be understood that the number of insertion holes 1001 may be less than the number of support portions 60, or the number of insertion holes 1001 may be more than the number of support portions 60; for example, some support portions 60 may be provided with insertion holes 1001 for insertion and engagement with support portions 60; for example, each support portion 60 may be provided with insertion holes 1001 for insertion and engagement with support portions 60, etc. This embodiment is only for illustrative purposes and does not limit the number and form of insertion and engagement of support portions 60 and insertion holes 1001.

[0047] Preferably, the proximal end face of the guide head 90 is provided with a protrusion 110, which protrudes from the proximal end face of the guide head 90 toward the delivery device 10. The outer diameter of the protrusion 110 is smaller than the outer diameter of the proximal end face of the guide head 90, so that the proximal end face of the guide head 90 forms a stepped surface 120, and the clearance hole 100 is located on the stepped surface 120. The distal end of the core tube 80 is fixedly connected to a fixing part 130 for connecting the core tube 80 and the guide head 90; the protrusion 110 is located at the distal end of the fixing part 130, and there is a gap between the protrusion 110 and the fixing part 130. This gap forms an annular groove 140 for receiving the proximal end of the stent, so as to further stably confine the vascular stent 20 connected to the support part 60 within the delivery device 10 and prevent the connection part 2021 of the vascular stent 20 from sliding out of the support part 60.

[0048] refer to Figure 8 and Figure 9When the vascular stent 20 needs to be released, the sheath 30 can be pulled towards the proximal end (rearward) of the delivery device 10 to allow the main body section 201 of the vascular stent 20 to expand. At this time, the connecting section 202 of the vascular stent 20 is still attached to the supporting parts 60 of the support member 41. Then, the push tube 501 is pulled towards the proximal end (rearward) of the delivery device 10, so that a portion of the supporting parts 60 (i.e., the second supporting part 602 in this embodiment) is released from the corresponding clearance hole 100 until a portion of the connecting part 2021 of the vascular stent 20 is released from the second supporting part 602. Finally, the push tube 501 is pulled further towards the proximal end (rearward), so that another portion (i.e., the first supporting part 601 in this embodiment) is released from the corresponding clearance hole 100 until the remaining connecting part 2021 of the vascular stent 20 is released from the first supporting part 601, thereby completing the stepwise release of the vascular stent 20.

[0049] The delivery device 10 enables the step-by-step release of the connecting section 202 of the vascular stent 20, thereby dispersing and unloading the force of the connecting section 202 springing outward in multiple steps, reducing the risk of further damage to physiological tissues such as the blood vessel wall during the release of the vascular stent 20, making the surgical procedure safer and more stable.

[0050] The above are merely preferred embodiments of the present invention. The scope of protection of the present invention is not limited to the embodiments listed above. Any simple changes or equivalent substitutions of the technical solutions that can be obviously obtained by those skilled in the art within the scope of the technology disclosed in the present invention shall fall within the scope of protection of the present invention.

Claims

1. A conveying device for conveying supports, characterized in that, The delivery device includes a sheath for housing a stent and a support slidably disposed within the sheath. The support includes a pushing portion and a plurality of supporting portions disposed on the pushing portion, wherein the distal ends of at least two supporting portions are not flush with each other, so that the proximal end of the stent can be released from the support in stages. The delivery device also includes a core tube passing through the support and a guide head disposed on the core tube. The guide head is located at the distal end of the support, and the pushing portion is slidably sleeved on the core tube. The guide head is provided with a plurality of clearance holes, each supporting portion corresponding to a clearance hole that can be inserted and mated with it. The supporting portion includes a first supporting portion and a second supporting portion, wherein the distal end of the first supporting portion protrudes beyond the distal end of the second supporting portion, and the first supporting portion and the second supporting portion are arranged alternately in the circumferential direction. The conveying device further includes a fixing part for connecting the core tube and the guide head. The proximal end face of the guide head is provided with a protrusion. The protrusion protrudes from the proximal end face of the guide head toward the proximal end of the conveying device. The outer diameter of the protrusion is smaller than the outer diameter of the proximal end face of the guide head, so that the proximal end face of the guide head forms a stepped surface. The clearance hole is located on the stepped surface. The protrusion is located at the distal end of the fixing part. The protrusion and the fixing part are spaced apart. The space forms an annular groove for receiving the proximal end of the support.

2. The delivery device of claim 1, wherein, The multiple support portions are distributed at intervals along the circumference of the push portion.

3. The delivery device of claim 1, wherein, The support member includes 2 to 10 of the aforementioned support portions.

4. The delivery device of claim 1, wherein, The pushing part includes a pushing tube and a fixing seat disposed on the pushing tube, and a plurality of the supporting parts are disposed on the fixing seat.

5. The delivery device of claim 4, wherein, The fixing base includes a connecting pipe disposed on the push tube and a fixing block disposed on the connecting pipe, and the plurality of support parts are disposed on the fixing block.

6. The delivery device of claim 1, wherein, The clearance hole extends axially from the proximal end face of the guide head toward the distal end of the guide head.

7. A delivery system characterized by, The delivery system includes a delivery device according to any one of claims 1 to 6 and a support for housing within the sheath, the support having a plurality of connecting portions at its proximal end, the plurality of connecting portions being releasably connected to corresponding support portions.

8. The conveying system according to claim 7, characterized in that, A support tube is provided between the support member and the sheath. An annular space for accommodating the stent is formed between the distal end of the support tube and the proximal end of the plurality of support parts. The distal end of the support tube is used to contact the distal end of the stent to support the stent.

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