A stent delivery system

Abstract

The present disclosure relates to a stent delivery system, which comprises: a catheter and a delivery guide wire inside the catheter. The proximal end of the delivery guide wire is connected to an operating handle, and the distal end is connected to a hypotube and a braided tube. The distal end of the braided tube is connected to a tip portion to form a guide wire passage of a protective device. A connecting tube is installed at the distal end of the hypotube, and a clamping portion is installed on the connecting tube. One end of the clamping portion is fixed on the connecting tube, and the other end can slide on the connecting tube with a slider. The end of the stent is clamped with the clamping portion of the connecting tube to fix the stent on the connecting tube. The clamping teeth of the clamping portion lock the stent to prevent premature ejection during the release process of the stent, thereby improving the success rate of the operation. The clamping teeth of the clamping portion are rounded, and the clamping teeth stress can be released by sliding the slider when loading the stent, which greatly reduces the damage of the clamping teeth to the stent and avoids the damaged stent from causing harm to the human body. The clamping portion uses soft wire material, and the double wire structure and slider design make it not hinder the recovery of the delivery system.

Description

Technical Field

[0001] The present disclosure relates to the field of medical devices, and in particular to a stent delivery system. Background Art

[0002] The carotid artery is a large blood vessel that transports blood from the heart to the head, face, and neck. It is one of the main blood vessels supplying the brain. Carotid artery stenosis is the main risk factor and etiological basis for ischemic cerebrovascular disease. 25% of ischemic strokes are related to carotid artery stenosis or occlusion.

[0003] Carotid artery stenosis is a common disease, including congenital and acquired carotid artery stenosis. This disease can seriously affect the blood flow, resulting in insufficient blood and oxygen supply to the whole body. At present, the treatments for carotid artery stenosis mainly include medical medication, carotid endarterectomy (CEA) and carotid angioplasty and stenting (CAS). In the past 20 years, with the increasing maturity of neuroimaging and neurointerventional technology, the improvement of interventional materials and the improvement of operator skills, carotid artery stenting has become one of the main treatments for carotid artery stenosis due to its safety, effectiveness, minimal invasiveness and significant efficacy.

[0004] At present, there are two main types of carotid artery stents, one is a braided stent and the other is a laser-engraved stent. Compared with braided stents, laser-engraved stents provide better support to blood vessels. However, the high support causes the risk of the stent popping out of the delivery system prematurely near the end of its release. A stent that pops out prematurely cannot completely cover the lesion, easily causing surgical failure. Summary of the invention

[0005] In order to overcome the deficiencies of the prior art, the present invention aims to provide a stent delivery system to solve the above-mentioned technical problems.

[0006] In order to achieve the above object, the present disclosure provides a stent delivery system, the stent delivery system comprising:

[0007] catheter;

[0008] a delivery guidewire, the delivery guidewire being disposed in the catheter;

[0009] A hypotube, wherein the hypotube is disposed in the catheter, and the proximal end of the hypotube is connected to the distal end of the delivery guidewire;

[0010] A connecting tube, the connecting tube is arranged in the catheter, and the proximal end of the connecting tube is connected to the hypotube;

[0011] A clamping portion, at least a portion of which is fixedly disposed on the outer wall of the connecting pipe;

[0012] The bracket is sleeved on the connecting tube, the proximal end of the bracket is clamped with the clamping part, and the bracket is configured to be disengaged from the clamping part after being pushed out of the catheter.

[0013] In some embodiments, the stent delivery system further comprises:

[0014] A braided tube, wherein the braided tube is disposed in the hypotube, and the proximal end of the braided tube is connected to the distal end of the delivery guide wire;

[0015] A tip portion is arranged on the distal end side of the connecting tube, and a proximal end of the tip portion is connected to the distal end of the braided tube.

[0016] In some embodiments, the engaging portion includes a locking tooth and a sliding block;

[0017] The sliding block is sleeved on the connecting pipe and can slide along the connecting pipe;

[0018] An end portion of the latching tooth is at least partially fixed on the sliding block, and another end portion of the latching tooth is at least partially fixed on the connecting pipe.

[0019] In some embodiments, the material of the clamping teeth is stainless steel wire, platinum-tungsten alloy wire, platinum-iridium alloy wire, tungsten wire or polymer material wire.

[0020] In some embodiments, the stent includes end portions and a middle portion;

[0021] The stent wires at the end are sparser than the stent wires in the middle.

[0022] In some embodiments, the stent is in a compressed state and has a plurality of ring structures;

[0023] The annular structure at the end is connected to the annular structure in the middle via a first connecting bridge;

[0024] The multiple annular structures in the middle are connected by a second connecting bridge.

[0025] In some embodiments, the second connecting bridges between the multiple annular structures in the middle are distributed in a straight line in the axial direction.

[0026] In some embodiments, the second connecting bridges between the multiple annular structures in the middle portion are staggered in the axial direction.

[0027] In some embodiments, a first visualization marker is disposed at the distal end of the catheter;

[0028] A second development mark is arranged at the distal end of the hypotube.

[0029] In some solutions, a third imaging marker is provided at the proximal end of the tip portion.

[0030] The embodiments of the present disclosure provide a stent delivery system, including: a catheter, a delivery guide wire and a hypotube that are connected to each other and disposed inside the catheter. A connection tube is connected to the distal end of the hypotube, and a clamping portion is provided at the proximal end of the connection tube. The clamping portion includes a clamping tooth and a slider; the compressed stent is sleeved on the connection tube, and the stent wires at the end of the stent are sparser than those in the middle. The clamping teeth of the clamping portion are stuck in the sparse stent wires at the end of the stent, so that the stent will not slide axially. The stent is locked by the clamping teeth of the clamping portion to prevent the stent from popping out prematurely, improving the success rate of the operation; at the same time, the tips of the clamping teeth of the clamping portion are round, greatly reducing the damage of the clamping teeth to the stent and avoiding the harm caused to the human body by the damaged stent; the design of the clamping teeth with a double-wire structure and the slider can release the stress of the catheter on the clamping portion when the delivery system is retrieved, so that it can be smoothly withdrawn into the sheath tube and is not likely to damage the blood vessel. Description of the Drawings

[0031] Figure 1 is a schematic structural diagram of the stent delivery system provided by the embodiments of the present disclosure;

[0032] Figure 1a is Figure 1 a partial enlarged view of A in

[0033] Figure 2 is a schematic structural diagram one of the clamping portion provided by the embodiments of the present disclosure;

[0034] Figure 2a is a schematic structural diagram two of the clamping portion provided by the embodiments of the present disclosure;

[0035] Figure 2b is a schematic structural diagram three of the clamping portion provided by the embodiments of the present disclosure;

[0036] Figure 2c is a schematic structural diagram four of the clamping portion provided by the embodiments of the present disclosure;

[0037] Figure 3 is an axial schematic diagram of the clamping portion when the stent delivery system provided by the embodiments of the present disclosure delivers a stent;

[0038] Figure 4 is a schematic structural diagram of the stent in a compressed state provided by the embodiments of the present disclosure;

[0039] Figure 5 is a schematic structural diagram one of the braiding method of the stent provided by the embodiments of the present disclosure;

[0040] Figure 6 is a schematic structural diagram two of the braiding method of the stent provided by the embodiments of the present disclosure;

[0041] Figure 7 The third structural schematic diagram of the weaving method of the stent provided in the embodiment of the present disclosure. DETAILED DESCRIPTION

[0042] The technical solution of the present disclosure is further described in detail below through the accompanying drawings and embodiments.

[0043] The disclosed embodiment provides a stent delivery system, including: a catheter, a delivery guide wire and a hypotube that are interconnected and disposed in the catheter, the distal end of the hypotube is connected to a connecting tube, the proximal end of the connecting tube is provided with a clamping portion, the clamping portion includes a clamping tooth and a slider; the compressed stent is sleeved on the connecting tube, the stent wires at the end of the stent are sparser than the stent wires in the middle, the clamping teeth of the clamping portion are clamped in the sparse stent wires at the end of the stent, so that the stent does not slide axially. The clamping teeth of the clamping portion lock the stent to prevent the stent from popping out prematurely, thereby improving the success rate of the operation; at the same time, the clamping teeth of the clamping portion have rounded tips, which greatly reduces the damage of the clamping teeth to the stent, and avoids the damaged stent from causing harm to the human body; the clamping teeth of the double-wire structure and the slider design can release the stress of the catheter on the clamping portion when the delivery system is recovered, so that it can be smoothly withdrawn into the sheath tube without damaging the blood vessels.

[0044] The present disclosure is described in detail below through specific embodiments, but it should be understood that the following embodiments are not intended to limit the present disclosure, and those skilled in the art can conceive of arranging and combining the specific features in the embodiments to form other similar schemes based on the concept of the present disclosure.

[0045] As discussed in the present disclosure, the terms "distal" or "proximal" are used in the following descriptions of the position or direction relative to the handheld terminal of the treating physician or medical interventionist. "Distal" or "distal side" refers to the position away from the handheld terminal of the physician or interventionist, and the position is not limited to a specific endpoint, but can also be a position close to the endpoint. "Proximal" or "proximal side" refers to the position close to the handheld terminal of the physician or interventionist.

[0046] Figure 1 A schematic diagram of the structure of a stent delivery system provided in an embodiment of the present disclosure; Figure 1a for Figure 1 A local enlarged view of the middle A; Figure 1 and Figure 1a As shown, the stent delivery system includes: a catheter 1, a delivery guide wire 2, a hypotube 3, a connecting tube 4, a clamping portion 5, a stent 6, a braided tube 7, a tip portion 8, a Y-type valve 9 and a handle 10.

[0047] The catheter 1 is a commonly used medical catheter used to establish a delivery pathway for a stent delivery system. A Y-shaped valve 9 is connected to the proximal end of the catheter 1 , and a first development marker 11 is provided at the distal end of the catheter 1 .

[0048] The delivery guide wire 2 for delivery operation is arranged inside the catheter 1. A hypotube 3 is arranged at the distal end of the delivery guide wire 2. A second imaging marker 31 is arranged at the distal end of the hypotube 3. The hypotube 3 is arranged inside the catheter 1, and the proximal end of the hypotube 3 is connected to the distal end of the delivery guide wire 2; a connecting tube 4 is arranged at the distal end of the hypotube 3. The connecting tube 4 is arranged inside the catheter 1, and the proximal end of the connecting tube 4 is connected to the distal end of the hypotube 3; a clamping portion 5 is arranged on the outer wall of the connecting tube 4 for locking the stent 6 to be delivered; the stent 6 is a reticulated open-loop structure. During delivery, the stent 6 is compressed inside the catheter 1 and sleeved on the connecting tube 4. One end of the stent 6 is clamped on the clamping portion 5, and the stent 6 is clamped on the connecting tube 4 through the clamping portion 5 to prevent the stent 6 from popping out prematurely during the delivery process.

[0049] A braided tube 7 is further arranged inside the hypotube 3. The proximal end of the braided tube 7 is connected to the distal end of the delivery guide wire 2. The distal end of the braided tube 7 is connected to a tip portion 8. A third imaging marker 81 is arranged at the proximal end of the tip portion 8, which can be used to observe and locate the distal end of the stent 6 during the operation. The tip portion 8 is made of silicone material with a hardness of 30-60A. Compared with other carotid artery stent products, its hardness is smaller, which can effectively reduce the damage to blood vessels; the tip portion 8 is connected to the braided tube 7 to form a protection device wire passage.

[0050] Figure 2 One of the structural schematic diagrams of the clamping portion provided by the embodiment of the present disclosure Figure 3 The axial schematic diagram of the clamping portion during stent delivery of the stent delivery system provided by the embodiment of the present disclosure is as Figure 2 and Figure 3 shown. The clamping portion 5 is fixedly arranged at the proximal end of the connecting tube 4. The clamping portion 5 includes a clamping tooth 51 and a slider 52. Among them, the slider 52 is a ring structure sleeved on the proximal end of the connecting tube 4 and can slide along the connecting tube 4; the clamping tooth 51 is a double-wire structure formed by bending a wire. The clamping tooth 51 can be made of metal wires such as stainless steel wire, platinum-tungsten alloy wire, platinum-iridium alloy wire, nitinol alloy wire or tungsten wire, or can also be made of a polymer material wire with a certain strength and flexibility. The proximal end of the clamping tooth 51 is fixed on the slider 52 and can slide with the slider 52. The distal end of the clamping tooth 51 is fixed on the connecting tube 4.

[0051] Figures 2a - 2c Schematic diagrams of several other different structures of the clamping portion provided by the embodiment of the present disclosure. This structure is easier to implement compared to the structure shown in Figure 2 shown, but appropriate materials should be selected to ensure that the expected effect is achieved without damaging the blood vessels and the stent. As Figure 2aThe clamping portion 5 shown is fixedly arranged at the proximal end of the connecting tube 4. The clamping portion 5 only includes a clamping tooth 51 and no slider. The clamping tooth 51 is a double-wire structure formed by bending a wire. Both ends of the clamping tooth 51 are fixed on the connecting tube 4. The clamping tooth 51 can be embedded in the bracket 6 to lock the bracket 6 on the connecting tube 4.

[0052] like Figure 2b The clamping portion 5 shown is fixedly arranged at the proximal end of the connecting tube 4. The clamping portion 5 only includes a clamping tooth 51 and no slider. The clamping tooth 51 is a monofilament structure. The distal end of the clamping tooth 51 is fixed on the connecting tube 4, and the proximal end is not fixed. There is a certain angle between the clamping tooth 51 and the connecting tube 4, which is in a barb shape and can clamp the bracket 6 to lock the bracket 6 on the connecting tube 4.

[0053] Furthermore, if Figure 2c The illustrated engaging portion 5 comprises multiple circles of monofilament structured engaging teeth 51 , and the engaging teeth 51 of each circle may be aligned with each other or staggered at a certain angle.

[0054] Figures 4 - 7 A schematic diagram of the structure of the bracket provided in the embodiment of the present disclosure, as shown in Figures 4 - 7 As shown, the bracket 6 includes an end portion 61 and a middle portion 62, wherein, in order to enable the bracket 6 to be clamped with the clamping portion 5, the bracket wires at the end portion 61 are sparser than the bracket wires at the middle portion 62, so that when the bracket 6 is compressed, there are gaps between the bracket wires at the end portion 61, which facilitates the insertion of the clamping teeth 51 of the clamping portion 5 to clamp the bracket 6.

[0055] The stent 6 is a mesh open-loop structure, which is laser engraved and made of nickel-titanium alloy. During production, a multi-segment structure of "sparse-dense-sparse" is adopted, that is, the number of stent wires at the two ends 61 is small, and the number of stent wires in the middle part 62 is large, so that the end 61 is more sparse. The sparse end 61 is convenient for clamping with the clamping teeth 51 of the clamping part 5, so that the stent 6 can be clamped on the connecting tube 4 to prevent premature ejection during the release process; the dense middle part 62 can provide a higher metal coverage rate and improve the success rate of the operation. The stent 6 is presented as a plurality of annular structures, and the plurality of annular structures are connected by connecting bridges. Specifically, the annular structure of the end 61 is connected to the annular structure of the middle 62 by a plurality of first connecting bridges 611, and the plurality of annular structures in the middle 62 are connected by a plurality of second connecting bridges 621.

[0056] In some preferred embodiments, Figures 5 - 7 As shown, the metal wires of the ring structure of the end 61 are 24 metal wires, and the metal wires of the ring structure of the middle part 62 are 36 metal wires. The metal wires of the end 61 are longer than the metal wires of the middle part 62, so as to produce a stent with sparse ends and dense middle.

[0057] The annular structure of the end portion 61 is connected to the annular structure of the middle portion 62 by six first connecting bridges 611, and every two annular structures of the middle portion 62 can be connected by six second connecting bridges 621, or nine second connecting bridges 621. The second connecting bridges 621 between the multiple annular structures of the middle portion 62 can be connected to each other in a straight line in the axial direction, that is, the multiple second connecting bridges 621 are distributed in a straight line in the axial direction, and this structure can reduce the shortening of the stent while ensuring the flexibility of the stent; the second connecting bridges 621 between the multiple annular structures of the middle portion 62 can also be connected in a wave-like manner, that is, the multiple second connecting bridges 621 are staggered in the axial direction, and the stent with this structure can increase the flexibility of the stent.

[0058] When the bracket 6 is loaded, Figure 2 As shown, the arrow direction in the figure is the loading direction of the stent 6. The stent 6 is compressed into a bundle and is sleeved on the connecting tube 4 from the distal end to the proximal end. When the stent 6 is sleeved to the clamping portion 5, the clamping teeth 51 are squeezed inward by the stent 6. At this time, the slider 52 slides in the opposite direction of the sleeve direction of the stent 6 to prevent the clamping teeth 51 from being excessively squeezed and damaging the inner surface of the stent 6; when the stent 6 is loaded in place, the clamping teeth 51 and the slider 52 return to their original state, and the clamping teeth 51 are clamped into the sparse mesh at the end of the stent 6, thereby locking the stent 6 and fixing it. A plurality of clamping teeth 51 can be set around the slider 52, and the specific number can be set as needed. The clamping teeth 51 of the double-wire structure can lock the stent 6 more firmly, and its tip is rounded, which can reduce damage to the stent 6. At the same time, when the stent delivery system is recovered, the design of the clamping teeth 51 and the slider 52 combined with the double-wire structure is easier to release the stress in contact with the catheter 1, so that it is easier to withdraw into the catheter 1.

[0059] When the stent 6 is transported, it is confirmed that the stent 6 is transported to the optimal position by observing the first development mark 11 , the second development mark 31 , and the third development mark 81 .

[0060] When the stent 6 is released, the latching teeth 51 of the clamping part 5 can firmly lock the stent 6. Only when the clamping part 5 releases the catheter 1, the stent 6 is separated from the clamping part 5, and the stent 6 is completely released. This design can effectively avoid the problem of the stent 6 popping out prematurely during the release process. The latching teeth 51 of the clamping part 5 are soft wires with rounded heads, which do not affect the recovery of the stent delivery system and will not puncture the blood vessels. When performing the release operation, the Y-type valve 9 is withdrawn while the handle 10 is fixed. The Y-type valve 9 drives the catheter 1 to withdraw, gradually exposing the stent 6. When the stent 6 and the clamping part 5 are completely exposed at the distal end of the catheter 1, the stent 6 automatically opens and disengages from the clamping part 5, sticks to the inner wall of the blood vessel, and then withdraws the handle 10 to withdraw the sea wave tube 3, the connecting tube 4 and the tip 8 into the catheter 1, and the entire stent delivery system is withdrawn from the body with the catheter 1.

[0061] The disclosed embodiment provides a stent delivery system, including: a catheter, a delivery guide wire and a hypotube that are interconnected and disposed in the catheter, the distal end of the hypotube is connected to a connecting tube, the proximal end of the connecting tube is provided with a clamping portion, the clamping portion includes a clamping tooth and a slider; the compressed stent is sleeved on the connecting tube, the stent wires at the end of the stent are sparser than the stent wires in the middle, the clamping teeth of the clamping portion are clamped in the sparse stent wires at the end of the stent, so that the stent does not slide axially. The clamping teeth of the clamping portion lock the stent to prevent the stent from popping out prematurely, thereby improving the success rate of the operation; at the same time, the clamping teeth of the clamping portion have rounded tips, which greatly reduces the damage of the clamping teeth to the stent, and avoids the damaged stent from causing harm to the human body; the clamping teeth of the double-wire structure and the slider design can release the stress of the catheter on the clamping portion when the delivery system is recovered, so that it can be smoothly withdrawn into the sheath tube without damaging the blood vessels.

[0062] The specific implementation methods described above further illustrate the objectives, technical solutions and beneficial effects of the present disclosure in detail. It should be understood that the above description is only the specific implementation methods of the present disclosure and is not intended to limit the protection scope of the present disclosure. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present disclosure should be included in the protection scope of the present disclosure.

Claims

1. A stent delivery system, characterized in that, The stent delivery system comprises: catheter; a delivery guidewire, the delivery guidewire being disposed in the catheter; A hypotube, wherein the hypotube is disposed in the catheter, and the proximal end of the hypotube is connected to the distal end of the delivery guidewire; A connecting tube, the connecting tube is arranged in the catheter, and the proximal end of the connecting tube is connected to the hypotube; A clamping portion, at least part of which is fixedly disposed on the outer wall of the connecting pipe; the clamping portion comprises a clamping tooth and a sliding block; The sliding block is sleeved on the connecting pipe and can slide along the connecting pipe; The end of the latch tooth is at least partially fixed on the slider, and the other end of the latch tooth is at least partially fixed on the connecting tube; the latch tooth is a double-wire structure, formed by bending a wire, and the tip of the latch tooth is rounded; The stent is a mesh open-loop structure formed by laser engraving, the stent is sleeved on the connecting tube, the proximal mesh of the stent is engaged with the engaging teeth of the engaging portion, and the stent is configured to be disengaged from the engaging portion after being pushed out of the catheter; A braided tube, wherein the braided tube is disposed in the hypotube, and the proximal end of the braided tube is connected to the distal end of the delivery guide wire; A tip portion is arranged on the distal end side of the connecting tube, and a proximal end of the tip portion is connected to the distal end of the braided tube.

2. The stent delivery system according to claim 1, wherein The material of the clamping teeth is stainless steel wire, platinum-tungsten alloy wire, platinum-iridium alloy wire, tungsten wire or polymer material wire.

3. The stent delivery system according to claim 1, characterized in that, The bracket includes an end portion and a middle portion; The stent wires at the end are sparser than the stent wires in the middle.

4. The stent delivery system according to claim 3, wherein The stent is in a compressed state and presents a plurality of ring-shaped structures; The annular structure at the end is connected to the annular structure in the middle via a first connecting bridge; The multiple annular structures in the middle are connected by a second connecting bridge.

5. The stent delivery system according to claim 4, wherein The second connecting bridges between the multiple annular structures in the middle are distributed in a straight line in the axial direction.

6. The stent delivery system according to claim 4, wherein The second connecting bridges between the multiple annular structures in the middle are staggeredly distributed in the axial direction.

7. The stent delivery system according to claim 1, wherein The distal end of the catheter is provided with a first development mark; A second development mark is arranged at the distal end of the hypotube.

8. The stent delivery system according to claim 1, wherein A third developing mark is disposed at the proximal end of the tip portion.

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