Delivery catheter and distal protection system

Abstract

The invention particularly relates to a delivery catheter and a far-end protection system.The delivery catheter comprises a catheter body and a guiding part, the guiding part is arranged at the far end of the catheter body, and a guiding face is arranged on the end face of the end, away from the catheter body, of the guiding part. The guide part is provided with a conveying channel, the conveying channel and the pipe body are coaxially arranged, the conveying channel has a first state and a second state which can be switched, the conveying channel has a first inner diameter in the first state, the conveying channel has a second inner diameter in the second state, and the first inner diameter is smaller than the second inner diameter and smaller than the inner diameter of the pipe body. According to the conveying catheter, in the recovery process of the protection umbrella assembly, the far-end protection device and the conveying catheter are always kept on the same axial center line through guiding of the guiding face and constraint of the conveying channel on the conveying rod, and then the problem that when the protection umbrella is collected into the conveying catheter, the conveying catheter cannot be damaged is solved. The conveying rod and the catheter cannot be centered due to a step difference, so that the conveying rod and the catheter are blocked or cannot be collected into the conveying catheter at one time.

Description

Technical Field

[0001] The present invention belongs to the technical field of medical devices, and in particular relates to a delivery catheter and a distal protection system. Background Art

[0002] Health is a common goal that humans need to face, and disease treatment is a common challenge for society. Neurological stroke is one of the major life-threatening diseases with a high incidence rate, mainly including ischemic stroke and hemorrhagic stroke.

[0003] Ischemic disease is one of the most common symptoms of stroke. The cause of ischemic stroke is small emboli on the inner wall of the blood vessels supplying the brain, which can cause arterial embolism after falling off. The heart valves of patients with coronary heart disease and atrial fibrillation are prone to mural thrombosis. After the emboli fall off, they can block the cerebral blood vessels and also cause ischemic stroke. Other factors include hypertension, diabetes, and hyperlipidemia. In addition, intimal hyperplasia and hypertrophy caused by collagen diseases, arterial changes in hypertension, rheumatic heart disease sugar or arteritis, blood diseases, metabolic diseases, etc., carotid artery trauma, tumor compression of the carotid artery, etc. can all cause stenosis and occlusion of the internal carotid artery, or cause stroke due to ruptured blood vessels and bleeding.

[0004] In recent years, stroke has become the second leading cause of death in the world after ischemic heart disease, and is the most important factor in human disability. Among them, more than 80% of strokes are ischemic strokes, and about 20% are hemorrhagic strokes. Ischemic strokes are mainly caused by insufficient blood supply to the brain or cerebral embolism due to carotid artery stenosis and intracranial vascular stenosis, while hemorrhagic strokes are mainly caused by subarachnoid hemorrhage caused by rupture of cerebral aneurysms. In recent years, interventional devices such as carotid artery stents, distal protection devices, and intracranial vascular stents have been developed for ischemic stroke, and coils and related stent technologies have been developed for interventional treatment of cerebral aneurysms, which play a major role in the safety and effectiveness of treatment.

[0005] Ischemic disease is one of the most common symptoms of stroke. The cause of ischemic stroke is the erosion or rupture of unstable plaques, followed by the flow of plaque fragments or thrombotic debris into the distal microcirculation, leading to embolism. The heart valves of patients with coronary heart disease and atrial fibrillation are prone to mural thrombosis. After the thrombus falls off, it can block the cerebral blood vessels and also cause ischemic stroke. Other factors include hypertension, diabetes, hyperlipidemia, etc. In addition, collagen diseases, arterial changes in hypertension, rheumatic heart disease, diabetes or arteritis, blood diseases, metabolic diseases, etc. cause intimal hyperplasia and hypertrophy, carotid artery trauma, tumor compression of the carotid artery, etc. can all cause stenosis and occlusion of the internal carotid artery, or cause stroke due to ruptured blood vessels and bleeding.

[0006] Distal protector: It is mainly used to collect plaques in the distal diseased blood vessels (intracranial internal carotid artery) during carotid artery stent intervention (CAS) to prevent distal cerebral vascular embolism. The product is pre-installed in a micro-delivery sheath (diameter 2.5~4F, about 0.83mm~1.33mm). After reaching the distal blood vessel, the sheath can automatically restore its umbrella shape after withdrawal, which can effectively capture the thrombus and atherosclerotic plaque that fall off during the stent intervention, thereby greatly increasing the safety of carotid artery stenting and reducing the incidence of postoperative complications.

[0007] At present, the proximal and distal ends of the protective umbrella of the distal protection device are mainly connected and fixed by clamping the filter screen with the inner ring and the outer ring, so that there is a large step difference between the fixed end face and the conveying rod (such as Figure 1 As shown in the figure, the difference in diameter between the delivery rod and the recovery end of the delivery catheter leads to a large gap and they are not on the same axial line. The two factors cause the protective umbrella to get stuck during the process of being retracted into the delivery catheter and cannot be retracted into the delivery catheter in one go. In severe cases, it may not be able to be retracted into the delivery catheter, which may easily lead to problems such as prolonged operation time and increase intraoperative risks. Summary of the invention

[0008] The purpose of the present invention is to at least solve the problem that when the protective umbrella of the existing distal protector is put into the delivery catheter, it cannot be aligned due to the step difference between the delivery rod and the catheter, resulting in jamming or failure to be put into the delivery catheter at one time. This purpose is achieved by the following technical solutions:

[0009] The present invention provides a delivery catheter for delivering a distal protection device, the delivery catheter comprising a tube body and a guide portion, the guide portion being arranged at the distal end of the tube body, the guide portion having a delivery channel for the distal protection device to pass through, and a guide surface being arranged on an end surface of the guide portion away from the tube body;

[0010] The delivery channel is coaxially arranged with the tube body, and has a switchable first state and a second state. In the first state, the delivery channel has a first inner diameter, and in the second state, the delivery channel has a second inner diameter. The first inner diameter is smaller than the second inner diameter and smaller than the inner diameter of the tube body.

[0011] According to the delivery catheter of the present invention, a guide part is provided at the distal end of the tube body, and the delivery channel of the guide part is limited to be coaxially provided with the tube body, and the delivery channel has a first state and a second state with different inner diameters, so that the protection umbrella component of the distal protection device can utilize the delivery channel of the guide part to constrain the delivery rod when it is recovered to the delivery channel, thereby keeping the distal protection device and the delivery catheter on the same axis center line, and at the same time, a guide surface is provided on the guide part, so that the guidance of the guide surface can be utilized to cooperate with the constraint of the delivery catheter so that the protection umbrella component can be smoothly received into the delivery catheter, which can effectively solve the problem that when the protection umbrella is received into the delivery catheter, it cannot be centered due to the step difference between the delivery rod and the catheter, resulting in jamming or failure to be received into the delivery catheter at one time, thereby avoiding repeated retraction operations during the operation, effectively shortening the operation time, and reducing the intraoperative risks such as vascular spasm caused by excessive stimulation of the blood vessels by the operation.

[0012] In addition, the delivery catheter according to the present invention may also have the following additional technical features:

[0013] In some embodiments of the present invention, along the axial direction of the tube body, the guide portion has a first cavity and a second cavity arranged in sequence, the second cavity and the first cavity are connected to the tube body in sequence, the first cavity and the second cavity are coaxially arranged, and the inner diameter of the second cavity is smaller than the inner diameter of the first cavity, and the second cavity is formed with the first inner diameter and the second inner diameter.

[0014] In some embodiments of the present invention, the inner diameter of the second cavity gradually decreases and then gradually increases along a first direction, and the first direction is the direction from the proximal end of the tube body to the distal end of the tube body.

[0015] In some embodiments of the present invention, the guiding portion has a third cavity, and the third cavity is arranged outside the second cavity.

[0016] In some embodiments of the present invention, the guide portion has an outer mesh tube and an inner mesh tube, and the outer mesh tube and the inner mesh tube are connected to form the first cavity, the second cavity and the third cavity.

[0017] In some embodiments of the present invention, the guide portion is a metal braid.

[0018] In some embodiments of the present invention, the guide portion and the tube body are integrally formed, the outer diameter of the guide portion gradually decreases along a first direction, the first direction is the direction from the proximal end of the tube body toward the distal end of the tube body, and the inner diameter of the guide portion is larger than the outer diameter of the distal protection device.

[0019] In some embodiments of the present invention, the guide portion is a polymer component, and a plurality of communication holes are formed on the guide portion, and the plurality of communication holes are arranged around the axis of the tube body.

[0020] In some embodiments of the present invention, a developing member is disposed at the distal end of the tube body, and along the axial direction of the tube body, the developing member is spaced apart from the guiding portion.

[0021] The second aspect of the present invention further provides a distal protection system, which includes the delivery catheter described in the present invention.

[0022] Compared with the prior art, the distal protection system proposed in the present invention has the technical advantages possessed by the above-mentioned delivery catheter, which will not be described in detail here. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Various other advantages and benefits will become apparent to those of ordinary skill in the art by reading the detailed description of the preferred embodiments below. The accompanying drawings are only for the purpose of illustrating the preferred embodiments and are not to be considered as limiting the present invention. Moreover, the same reference numerals are used throughout the accompanying drawings to represent the same components. In the accompanying drawings:

[0024] Figure 1 It is a schematic diagram of the structure of the existing distal protection system when it is recovered in the blood vessel;

[0025] Figure 2 A schematic diagram of a remote protection system according to an embodiment of the present invention is shown schematically;

[0026] Figure 3 for Figure 2 The structural schematic diagram of the remote protection device shown in;

[0027] Figure 4 for Figure 3 A local enlarged structural schematic diagram of A shown in ;

[0028] Figure 5 for Figure 2 A schematic diagram of the structure of the delivery catheter shown in ;

[0029] Figure 6 for Figure 5 A schematic diagram of the local enlarged structure of B shown in FIG.

[0030] Figure 7 for Figure 2 A schematic diagram of the structure of the guide portion shown in ;

[0031] Figure 8 for Figure 2 A schematic structural diagram of the guide portion shown in FIG. 1 from another viewing angle;

[0032] Fig. 9 for Figure 2 A schematic structural diagram of the guide portion shown in FIG. 1 under a third viewing angle;

[0033] Fig.10 The structure diagram of the braided mesh tube according to the embodiment of the present invention is schematically shown;

[0034] Fig.11 for Fig.10 A schematic diagram of the local enlarged structure of C shown in FIG.

[0035] Fig.12 for Figure 2 A schematic diagram of the structure of the distal protection device shown in FIG. 1 entering the delivery catheter during retrieval;

[0036] Fig.13 for Fig.10 Schematic diagram of the structural change of the guide portion during the recovery process shown in ;

[0037] Fig.14 A schematic diagram of a remote protection system according to an embodiment of the present invention is shown schematically;

[0038] Fig.15 for Fig.14 A schematic diagram of the structure of the delivery catheter shown in ;

[0039] Fig.16 for Fig.15 A schematic diagram of the local enlarged structure of D shown in FIG.

[0040] Fig.17 for Fig.14 A schematic diagram of the structure of the guide portion shown in FIG. 1 at a certain viewing angle;

[0041] Fig.18 for Fig.14 Schematic diagram of the structure of the guide part shown in another perspective.

[0042] The symbols in the accompanying drawings are as follows:

[0043] 1000, distal protection system; 2000, blood vessels;

[0044] 100. delivery catheter; 200. distal protection device;

[0045] 10. catheter; 11. tube body; 12. inner membrane; 13. guide part;

[0046] 20. Connector;

[0047] 30. Development parts;

[0048] 40, metal braided piece; 401, outer mesh tube; 402, inner mesh tube;

[0049] 41. first cavity; 42. second cavity; 421. inner bell mouth; 422. outer bell mouth; 43. third cavity; 431. outer fillet; 432. inner fillet;

[0050] 50. polymer part; 51. inlet; 52. connecting hole; 53. guide surface;

[0051] 60. Guide wire assembly; 61. Delivery rod; 611. Breaking point; 62. Development spring;

[0052] 70. Limiting parts;

[0053] 80, protective umbrella assembly; 81, first developing ring; 82, second developing ring; 821, inner ring; 822, outer ring; 83, filter screen; 84, developing wire;

[0054] 90. Braided mesh tube; 91. Metal wire. DETAILED DESCRIPTION

[0055] The exemplary embodiments of the present disclosure will be described in more detail below with reference to the accompanying drawings. Although the exemplary embodiments of the present disclosure are shown in the accompanying drawings, it should be understood that the present disclosure can be implemented in various forms and should not be limited by the embodiments described herein. On the contrary, these embodiments are provided in order to enable a more thorough understanding of the present disclosure and to fully convey the scope of the present disclosure to those skilled in the art.

[0056] It should be understood that the terms used herein are only for the purpose of describing specific example embodiments and are not intended to be limiting. Unless the context clearly indicates otherwise, the singular forms "one", "an" and "said" as used herein may also be meant to include plural forms. The terms "include", "comprise", "contain", and "have" are inclusive, and therefore specify the existence of stated features, steps, operations, elements and / or parts, but do not exclude the existence or addition of one or more other features, steps, operations, elements, parts, and / or combinations thereof. The method steps, processes, and operations described herein are not interpreted as necessarily requiring them to be performed in the specific order described or illustrated, unless the execution order is clearly indicated. It should also be understood that additional or alternative steps may be used.

[0057] Although the terms first, second, third, etc. can be used in the text to describe multiple elements, components, regions, layers and / or sections, these elements, components, regions, layers and / or sections should not be limited by these terms. These terms can only be used to distinguish an element, component, region, layer or section from another region, layer or section. Unless the context clearly indicates, terms such as "first", "second" and other numerical terms do not imply order or sequence when used in the text. Therefore, the first element, component, region, layer or section discussed below can be referred to as the second element, component, region, layer or section without departing from the teaching of the example embodiments.

[0058] For ease of description, spatial relative terms may be used herein to describe the relationship of one element or feature relative to another element or feature as shown in the figure, such as "inside", "outside", "inner side", "outer side", "below", "below", "above", "above", etc. Such spatial relative terms are intended to include different orientations of the device in use or operation in addition to the orientation depicted in the figure. For example, if the device in the figure is turned over, then the elements described as "below other elements or features" or "below other elements or features" will subsequently be oriented as "above other elements or features" or "above other elements or features". Therefore, the example term "below..." can include both upper and lower orientations. The device can be oriented otherwise (rotated 90 degrees or in other directions) and the spatial relative descriptors used in the text are interpreted accordingly.

[0059] In order to more clearly describe the structure of the present application, the terms "proximal end" and "distal end" are defined herein as commonly used terms in the field of interventional medicine. Specifically, "distal end" refers to the end away from the operator during the surgical operation, "proximal end" refers to the end close to the operator during the surgical operation, "axial" refers to its length direction, and "radial" refers to the direction perpendicular to the "axial" direction.

[0060] like Figure 1-Figure 18 As shown, the present invention proposes a delivery catheter 100 for delivering a distal protection device 200, so as to solve the problem that when the protective umbrella of the existing distal protector is put into the delivery catheter 100, it cannot be aligned due to the step difference between the delivery rod 61 and the catheter 10, resulting in jamming or failure to be put into the delivery catheter 100 at one time.

[0061] In terms of overall design, the delivery catheter 100 includes a tube body 11 and a guide portion 13. The guide portion 13 is disposed at the distal end of the tube body 11. The guide portion 13 has a delivery channel for the distal protection device 200 to pass through. A guide surface 53 is disposed on the end surface of the guide portion 13 that is away from the tube body 11. At the same time, the delivery channel is coaxially disposed with the tube body 11, and the delivery channel has a switchable first state and a second state. In the first state, the delivery channel has a first inner diameter, and in the second state, the delivery channel has a second inner diameter, the first inner diameter is smaller than the second inner diameter, and the first inner diameter is smaller than the inner diameter of the tube body 11.

[0062] Specifically, by providing a guide portion 13 at the distal end of the tube body 11, and limiting the delivery channel of the guide portion 13 to be coaxially arranged with the tube body 11, the delivery channel has a first state and a second state with different inner diameters, so that the protection umbrella of the distal protection device 200 can utilize the delivery channel of the guide portion 13 to constrain the delivery rod 61 when it is recovered to the delivery channel, thereby maintaining the distal protection device 200 and the delivery catheter 100 on the same axial center line. At the same time, by providing a guide surface 53 on the guide portion 13, the guidance of the guide surface 53 can be utilized to cooperate with the constraint of the delivery catheter 100 so that the protection umbrella can be smoothly collected into the delivery catheter 100. This can effectively solve the problem that when the protection umbrella is collected into the delivery catheter 100, it cannot be centered due to the step difference between the delivery rod 61 and the delivery catheter 100, resulting in jamming or failure to be collected into the delivery catheter 100 at one time, thereby avoiding repeated retraction operations during the operation, effectively shortening the operation time, and reducing the intraoperative risks such as excessive stimulation of the blood vessel 2000 and spasm of the blood vessel 2000.

[0063] It should be understood that the delivery catheter 100 is used to deliver the distal protection device 200, such as Figure 2 and Figure 3 As shown, the distal protection device 200 includes a guide wire assembly 60, a stopper 70 and a protective umbrella assembly 80. The guide wire assembly 60 includes a delivery rod 61 and a developing spring 62 arranged in sequence along a first direction a. Along the first direction a, the delivery rod 61 has a first section and a second section arranged in sequence. The diameter of the first section is greater than the diameter of the second section. The first section is provided with a breaking point 611. The end of the second section away from the first section is connected with a developing spring 62, that is, the developing spring 62 is fixed to the distal end of the delivery rod 61. In this embodiment, the developing spring 62 is fixed to the delivery rod 61 by welding or bonding. The developing spring 62 is wound with high-density precious metals such as platinum iridium, platinum tungsten, tantalum, gold, silver, platinum silver, platinum gold, etc., so that the position of the blood vessel 2000 reached by the delivery rod 61 can be determined by DSA subtraction technology during surgery. At the same time, the distal end of the developing spring 62 is welded or bonded to the delivery rod 61 to form a hemispherical shape to prevent the blood vessel 2000 from being punctured when the protective umbrella assembly 80 is released.

[0064] In the present embodiment, the limiter 70 and the protective umbrella assembly 80 are both arranged on the first section. The protective umbrella assembly 80 can move along the first direction a on the conveying rod 61, and at the same time, the limiter 70 can limit the moving distance of the protective umbrella assembly 80. In actual use, when the operator applies a pushing force or a pulling force to the conveying rod 61, the pushing force or the pulling force will be transmitted to the protective umbrella assembly 80 by the limiter 70 on the conveying rod 61, so as to push or withdraw the protective umbrella assembly 80, thereby completing the above-mentioned release process and recovery process. In the present embodiment, the limiter 70 is a tubular structure and is sleeved on the first section. Optionally, there is a first spacing between the limiter 70 and the distal end of the conveying rod 61, and the value range of the first spacing is between 20mm-50mm.

[0065] Still Figure 2 and Figure 3 As shown, along the first direction a, the protective umbrella assembly 80 includes a first developing ring 81, a filter 83, a developing wire 84 and a second developing ring 82. The filter 83 is made of a nickel-titanium wire 91 with shape memory properties woven into a mesh tube, and is made by heat treatment and finalization using a special mold. The filter 83 is designed as a trumpet structure, which is used to capture substances such as emboli and plaques that block the blood vessel 2000 after release to prevent the blockage of the blood vessel 2000 from causing a stroke.

[0066] In this embodiment, if Figure 4 As shown, the distal end of the filter 83 is clamped and fixed by the inner ring 821 and the outer ring 822, and is melted together by welding the outer end surface to form a second developing ring 82. Among them, the inner ring 821 and the outer ring 822 are both made of developing materials. Optionally, the developing material can be one or more of high-density precious metals such as platinum iridium, platinum tungsten, tantalum, gold, silver, platinum silver, platinum gold, etc., so that the developing effect can be achieved under the DSA subtraction technology, so that the release position of the protective umbrella assembly 80 can be accurately determined during the operation. Optionally, the outer diameter of the outer ring 822 is 0.40mm-0.80mm, the inner diameter of the outer ring 822 is 0.30mm-0.60mm, and the length of the outer ring 822 is 1.0mm-2.0mm. The inner ring 821 is disposed inside the outer ring 822, the outer diameter of the inner ring 821 is 0.20 mm-0.50 mm, the inner diameter of the inner ring 821 is 0.10 mm-0.30 mm, and the length L of the inner ring 821 is 1.0-2.0 mm. In this embodiment, the first developing ring 81 has the same structure as the second developing ring 82, that is, the inner ring 821 and the outer ring 822 are clamped and melted by welding the end faces at the proximal ends, thereby fixing the filter 83 and the developing wire 84.

[0067] It should be further understood that the maximum mesh area of ​​the filter 83 is not greater than 0.10 mm 2 , so set, can effectively capture an area not less than 0.10mm 2At the same time, a circle of developing wire 84 is sutured at the bell mouth of the proximal end of the filter 83. In this embodiment, the material of the developing wire 84 is one or more of developing precious metals such as platinum iridium, tantalum, gold, platinum silver, cobalt chromium platinum, etc. The diameter of the developing wire 84 is 0.03mm-0.08mm. By limiting the diameter of the developing wire 84, it can be developed under the DSA subtraction technology during the operation, and then the opening condition of the filter 83 can be observed to determine whether the opening end (bell mouth) of the filter 83 is attached to the wall of the blood vessel 2000.

[0068] like Figure 2 , Figure 5 , Fig.14 and Fig.15 As shown, the delivery catheter 100 includes a connector 20, a catheter 10 and a guide portion 13 arranged in sequence along a first direction a, wherein the connector 20 is a standard Luer connector 20, which is made by injection molding and is bonded and fixed to the proximal end of the catheter 10. During surgery, it can be connected to connectors such as a Y-valve and a hemostatic valve, which will not be described in detail here.

[0069] In this embodiment, the inner diameter of the catheter 10 is 1.0 mm-1.2 mm, the outer diameter of the catheter 10 is 1.3 mm-1.5 mm, and the total length of the catheter 10 is 1800 ± 20 mm. Specifically, the catheter 10 includes a tube body 11 and an inner membrane 12. The inner membrane 12 is arranged on the inner wall of the tube body 11, which not only facilitates the transportation of the distal protection device 200, but also reduces the damage of the tube body 11 to the distal protection device 200 during the transportation process. Optionally, the material of the tube body 11 is PEBAX polymer material, and the inner membrane 12 is PTFE inner membrane 12.

[0070] It should be further understood that a developing member 30 is provided at the distal end of the tube body 11, and the developing member 30 is spaced apart from the guide portion 13 along the axial direction of the tube body 11. By providing the developing member 30, the position of the distal end of the delivery catheter 100 in the blood vessel 2000 can be accurately observed during the operation, which helps to further improve the accuracy of the operation. Figure 5 and Figure 6As shown, in this embodiment, the developing member 30 is arranged between the PTFE inner membrane 12 and the catheter 10, and is embedded in the inner wall of the catheter 10. Optionally, the developing member 30 is set as an annular structure, the outer diameter of the developing member 30 is 1.26mm-1.46mm, the wall thickness of the developing member 30 is 0.1mm-0.2mm, the width of the developing member 30 is 1.0mm, and the material of the developing member 30 is one or more high-density precious metals such as platinum iridium, platinum tungsten, tantalum, gold, silver, platinum silver, platinum gold, etc., so that the distal end of the catheter 10 can be visualized during the operation, so that the doctor can judge the position of the delivery catheter 100 through the developing member 30. It can be understood that the tube body 11 is an integrated structure formed by extrusion of PEBAX polymer material, PTFE inner membrane 12 and developing member 30.

[0071] It can be understood that the guide portion 13 is arranged at the distal end of the tube body 11, and a guide surface 53 is arranged on the end surface of the guide portion 13 away from the tube body 11. The guide portion 13 and the tube body 11 can be a split structure, in which case the guide portion 13 can be fixed to the tube body 11 by hot melt technology and a removable heat shrink tube. Of course, the guide portion 13 and the tube body 11 can be an integrated structure, which helps to further reduce the difficulty of manufacturing the delivery catheter 100. The guide portion 13 has a delivery channel for the distal protection device 200 to pass through, and the delivery channel is coaxially arranged with the tube body 11. The delivery channel has a first state and a second state. When the distal protection device 200 is not inserted into the catheter 10, the guide portion 13 is in a natural state, that is, the first state. At this time, the delivery channel has a first inner diameter. When the distal protection device 200 is inserted into the catheter 10, since the outer diameter of the first developing ring 81 or the second developing ring 82 is greater than the first inner diameter, when the first developing ring 81 or the second developing ring 82 passes through the guide portion 13, the inner diameter of the delivery channel will be changed to ensure that the first developing ring 81 or the second developing ring 82 can pass through the guide portion 13. At this time, the delivery channel has a second inner diameter, that is, the delivery channel is in the second state. At the same time, the guide portion 13 has a restoring force for switching from the second state to the first state. It can be seen that when the distal protection device 200 passes through the delivery channel, the delivery channel can be switched between the first state and the second state. In the first state, the delivery channel has a first inner diameter, and in the second state, the delivery channel has a second inner diameter. The first inner diameter is smaller than the second inner diameter, and smaller than the inner diameter of the tube body 11.

[0072] During the operation for treating ischemic diseases, the delivery catheter 100 is used to place the distal protection device 3-5 cm away from the lesion and then release it, so that the distal protection device 200 can capture and recover the thrombus and plaque dropped during the operation, and prevent the distal blood vessel 2000 from being blocked and causing a stroke. At the same time, the distal protection device 200 can be delivered to the target location by pushing the delivery catheter 100, and released and recovered from the target location. During recovery, the distal protection device 200 can retract the protective umbrella assembly 80 into the delivery catheter 100 under the pulling action of the delivery rod 61. At this time, the guide portion 13 of the delivery catheter 100 can guide the protective umbrella assembly 80 into the delivery catheter 100, and constrain the delivery catheter 100 and the delivery rod 61 to remain on the same axial center line, thereby solving the problem of the protective umbrella being stuck or unable to be retracted into the delivery catheter 100 at one time due to the step difference between the delivery rod 61 and the catheter 10 when the protective umbrella is retracted into the delivery catheter 100, avoiding repeated retraction operations during the operation, effectively shortening the operation time, and reducing intraoperative risks such as spasm of the blood vessel 2000 caused by excessive stimulation of the operation.

[0073] It should be understood that when the guide portion 13 and the tube body 11 are configured as a separate structure, the guide portion 13 can be configured as a metal material or a polymer material. Figure 2-Figure 13 As shown, in this embodiment, the guide part 13 is set as a metal braided member 40. At this time, by utilizing the characteristics of metal and the braided structure, the guide part 13 can have better restraint, which helps to further ensure that during the recovery of the protective umbrella assembly 80, the delivery rod 61 and the delivery catheter 100 can always be on the same central axis, which helps to avoid the problem of multiple recovery or failure to recover due to jamming. Fig.10 and Fig.11 As shown, the metal braided member 40 includes a plurality of metal wires 91 , and the plurality of metal wires 91 are interlaced and woven into a braided mesh tube 90 , and then the braided mesh tube 90 is fixed in a special mold and subjected to heat treatment to obtain the above-mentioned guide portion 13 .

[0074] Furthermore, if Figure 7 As shown, along the axial direction of the tube body 11, the guide portion 13 has a first cavity 41 and a second cavity 42 arranged in sequence, the second cavity 42 and the first cavity 41 are connected to the tube body 11 in sequence, the first cavity 41 and the second cavity 42 are coaxially arranged, the inner diameter of the second cavity 42 is smaller than the inner diameter of the first cavity 41, and the second cavity 42 is formed with a first inner diameter and a second inner diameter.

[0075] Specifically, by limiting the guide portion 13 to have a first cavity 41 and a second cavity 42 arranged in sequence, the first cavity 41 can transition the connection between the interior of the tube body 11 and the second cavity 42, and the second cavity 42 has sufficient deformation space, as well as a force driving the second cavity 42 to return to the first state, which helps to ensure that the second cavity 42 constrains the guide wire assembly 60, so that the delivery rod 61 and the catheter 10 maintain the same axial center line.

[0076] It is important to understand that Figures 6 to 9 As shown, the guide portion 13 is made by a braided mesh tube 90 and has a first cavity 41 and a second cavity 42. In this embodiment, the inner diameter of the first cavity 41 is the same as the outer diameter of the tube body 11, and there is a tapered structure arranged along the first direction a between the first cavity 41 and the second cavity 42. At this time, the distal end of the tube body 11 can be inserted into the first cavity 41 of the guide portion 13, and connected together through hot melt technology and a removable heat shrink tube. Optionally, the first cavity 41 is entirely sleeved on the tube body 11 and is adapted to be connected with the distal end of the tube body 11. Of course, in addition to this, the first cavity 41 can be partially sleeved on the tube body 11, and the connection between the guide portion 13 and the tube body 11 can also be achieved. At the same time, the setting of the tapered structure can ensure that during the movement of the guide wire assembly 60, the second cavity 42 has a tendency to move radially toward the tube body 11 or along the first direction a, which helps to avoid the second cavity 42 moving in a direction away from the tube body 11, thereby blocking the distal end of the tube body 11.

[0077] It should be noted that the guide portion 13 can be set as Figures 6 to 9 The structure shown can also be set to other structures. When set to other structures, the gradual change of the tapered structure can be uniform or uneven, so as to ensure that the movement of the second cavity 42 is radially toward the tube 11 or along the first direction a. At the same time, the first cavity 41 can also be accommodated inside the tube 11, and in this case, the second cavity 42 is located outside the tube 11.

[0078] Furthermore, the inner diameter of the second cavity 42 first gradually decreases and then gradually increases along a first direction, and the first direction is a direction from the proximal end of the tube body 11 toward the distal end of the tube body 11 .

[0079] Specifically, by limiting the inner diameter of the second cavity 42 to gradually decrease and then gradually increase along the first direction, guide surfaces can be formed at both ends of the second cavity 42 to facilitate the passage of the protective umbrella assembly 80 in the second cavity 42, thereby helping to improve the efficiency of the operation.

[0080] It is important to understand that Figures 5 to 7As shown, along the first direction a, the inner diameter of the second cavity 42 first gradually decreases and then gradually increases, so that the two ends of the second cavity 42 form a trumpet-shaped guide surface 53. For the convenience of description, the guide surface 53 of the second cavity 42 facing the end of the tube body 11 is called the inner trumpet 421, and the guide surface 53 of the second cavity 42 away from the end of the tube body 11 is called the outer trumpet 422. Such a setting is not only convenient for the rapid guidance and restraint of the protective umbrella assembly 80 when the guide wire assembly 60 is recovered, but also can ensure the rapid output of the protective umbrella assembly 80 when pushing. Combined with the constraint of the second cavity 42 on the pushing rod, it helps to reduce the contact between the guide wire assembly 60 and the inner wall of the blood vessel 2000, thereby improving the safety of the operation.

[0081] It should be pointed out that, in addition to being configured as a trumpet-mouth shape, the two ends of the second cavity 42 can also be configured as a truncated cone structure to ensure rapid guidance of the protective umbrella assembly 80 .

[0082] Furthermore, the guiding portion 13 has a third cavity 43 , and the third cavity 43 is disposed outside the second cavity 42 .

[0083] Specifically, the provision of the third cavity 43 helps to further constrain the movement tendency of the guide portion 13 when the delivery channel switches between the first state and the second state, that is, the distal end of the guide portion 13 moves in a direction away from the tube body 11, and the second cavity 42 moves along the radial direction of the tube body 11, which helps to avoid the guide portion 13 blocking the tube body 11, and can effectively improve the use effect of the delivery catheter 100.

[0084] It is important to understand that Figures 5 to 7 As shown, after the braided mesh tube 90 is fixed by a special mold and heat-treated, the above-mentioned three-cavity two-bell mouth structure is formed, wherein the three cavities refer to the first cavity 41 and the second cavity 42 arranged in sequence, and the third cavity 43 arranged outside the second cavity 42. The two bell mouths refer to the bell mouth structure formed at both ends of the second cavity 42 along the axial direction of the tube body 11. Optionally, the outer diameter of the third cavity 43 is less than or equal to the outer diameter of the tube body 11. On the one hand, it can avoid the radial dimension of the distal end of the catheter 10 being too large, affecting the use of the catheter 10. On the other hand, when the guide wire assembly 60 passes through the second cavity 42, the third cavity 43 has a smaller moving space in the radial direction, thereby reducing the contact between the guide part 13 and the blood vessel 2000.

[0085] It should be further understood that the guide portion 13 has an outer mesh tube 401 and an inner mesh tube 402, which are connected to form a first cavity 41, a second cavity 42 and a third cavity 43. Setting the guide portion 13 as a two-layer structure helps to improve the restraining effect of the guide portion 13 itself and ensure that the second cavity 42 has a tendency to move toward the first direction a. It can also improve the connection effect between the guide portion 13 and the tube body 11. Since the guide portion 13 is a metal braid 40, the outer mesh tube 401 and the inner mesh tube 402 can be formed by folding and fixed together on the tube body 11, which helps to further ensure the fixing, guiding and restraining effects of the guide portion 13.

[0086] It should be noted that along the radial direction of the tube body 11, two correspondingly arranged outer fillets 431 and inner fillets 432 are formed at the distal end of the third cavity 43, wherein the inner fillet 432 is formed into the above-mentioned bell mouth structure, i.e., the guide surface 53. At the same time, the setting of the outer fillet 431 helps to further reduce the friction between the guide portion 13 and the blood vessel 2000, thereby ensuring the use effect of the guide portion 13.

[0087] Specifically, if Figures 6 to 11 As shown, the guide portion 13 is a Tip head arranged at the distal end of the delivery catheter 100. The Tip head is a ring-shaped mesh tube Tip head structure obtained by folding and fixing the braided mesh tube 90 on a special mold and then heat-treating it. Among them, the braided mesh tube 90 is a metal part. After folding, the braided mesh tube 90 forms an inner layer mesh tube 402 and an outer layer mesh tube 401. The free ends of the inner layer mesh tube 402 and the outer layer mesh tube 401 are connected together to enclose the above-mentioned first cavity 41, second cavity 42 and third cavity 43. At this time, the third cavity 43 is a hollow cavity (similar to the inflatable cavity of a lifebuoy) that is radially rotated 360° around the central axis of the braided mesh tube 90. The outer side of the third cavity 43 is the outer braided mesh tube 90 that has been folded and shaped. The end of the third cavity 43 that is away from the first cavity 41 is formed with a guide structure, which is the outer mesh tube 401 folded inward to form an outer fillet 431 transition arc surface, and then transitions to the second cavity 42 inward, and at the same time forms an arc surface with an inner fillet 432 transition, that is, a bell-mouth structure (guide surface 53). The bell-mouth structure is conducive to guiding the umbrella assembly 80 into the delivery catheter 100 when the umbrella is recovered. The diameter of the second cavity 42 is greater than the diameter of the delivery rod 61. The inner mesh tube 402 at the position of the second cavity 42 restrains the delivery rod 61 in the radial direction, so that the delivery rod 61 of the guide wire assembly 60 and the delivery catheter 100 are on the same axis center line.

[0088] When the protective umbrella assembly 80 is recovered and the delivery catheter 100 is pushed close to the first developing ring 81 of the protective umbrella assembly 80, the protective umbrella assembly 80 is guided and constrained by the trumpet structure of the Tip head so that the delivery rod 61 is aligned with the head end of the catheter 10, thereby being smoothly received into the catheter 10, effectively solving the problem of jamming or failure to recover caused by the step difference between the delivery rod 61 and the developing ring of the protective umbrella assembly 80, and the delivery rod 61 and the catheter 10 not being on the same axial center line, thereby avoiding intraoperative complications such as spasm of blood vessels 2000 caused by excessively long surgery time and reducing surgical risks.

[0089] The first cavity 41 is a cavity formed by the inner layer mesh tube 402 and the outer layer mesh tube 401 diverging from the second cavity 42 after being finalized. The size of the first cavity 41 is similar to the size of the inner cavity of the tube body 11. At this time, the radial outer side of the first cavity 41 is the Tip head mesh tube body composed of the inner layer mesh tube 402 and the outer layer mesh tube 401. The Tip head mesh tube body and the tube body 11 are melted by the hot melt technology to melt the polymer material of the tube body 11. After cooling, the Tip head mesh tube body is connected and fixed to the tube body 11 to form the Tip head of the delivery catheter 100. The first cavity 41 and the inner cavity of the tube body 11 together constitute the inner cavity of the delivery catheter 100. When the guidewire assembly 60 is recovered, the protective umbrella assembly 80 and the recovered thrombus plaque can be accommodated, and they can be withdrawn out of the body together with the delivery catheter 100 to prevent the thrombus plaque from flowing to the distal end of the blood vessel 2000 and causing a stroke.

[0090] When fixing the Tip head to the delivery catheter 100, first use the core shaft mold to support the inner cavity of the catheter 10, then put the Tip head on the outside of the distal end of the tube body 11, and then put a tearable heat shrink tube on the outside, and then use the hot melt technology to melt the polymer material of the tube body 11 and adhere it to the metal wire 91 of the Tip head. After cooling and shaping, fix the Tip head to the distal end of the tube body 11, and then tear off the tearable heat shrink tube to complete the fixation of the Tip head and the catheter 10.

[0091] like Fig.12 and Fig.13FIG. 1 shows the recovery process of the protective umbrella assembly 80 into the delivery catheter 100 . Before retrieving the protective umbrella assembly 80, the Tip head is in a naturally open state. At this time, the delivery rod 61 is restrained by the braided Tip head, and the position of the delivery rod 61 at the Tip head is on the same axis as the catheter 10; when the operator applies a pulling force to the delivery rod 61, the pulling force is transmitted to the protective umbrella assembly 80 through the limiter 70, so that the protective umbrella assembly 80 moves into the catheter 10 and retracts the first developing ring 81 into the catheter 10. At this time, the first developing ring 81 is smoothly retracted into the catheter 10 under the guidance of the trumpet structure (inner fillet 432) of the Tip head, and at the same time, the inner ring of the Tip head is expanded after being squeezed, so that the protective umbrella is smoothly retracted into the catheter 10, which solves the jamming problem caused by the distal protection device 200 not being on the same axial midline when being retracted into the catheter 10, thereby smoothly realizing one-time retraction into the catheter 10, avoiding repeated retraction operations during the operation, effectively shortening the operation time, and reducing the intraoperative risks such as spasm of the blood vessel 2000 caused by excessive operations. At the same time, when the protective umbrella component 80 is put into the catheter 10, the tip head is squeezed and the mesh becomes smaller, which can block the thrombus in the catheter 10 and prevent it from flowing to the distal end of the blood vessel 2000 again, effectively preventing the blockage of the distal blood vessel 2000 and causing a stroke.

[0092] It should be pointed out that in addition to being set as the above-mentioned ring-shaped network management Tip head structure, the guide portion 13 can also be set as other structures so as to have a tendency to recover from the second state to the first state, that is, a restraining force, and a guide surface 53 (external bell mouth 422 structure) located at the far end of the guide portion 13, and no further restrictions are imposed here.

[0093] In some other embodiments of the present application, when the guide portion 13 and the tube body 11 are integrally formed, such as Figure 14-18 As shown, the outer diameter of the guide portion 13 gradually decreases along the first direction a, and the inner diameter of the guide portion 13 is larger than the outer diameter of the distal protection device 200. By arranging the guide portion 13 and the tube body 11 to be integrally formed, it is convenient to reduce the difficulty of manufacturing the catheter 10. At the same time, limiting the outer diameter of the guide portion 13 to gradually decrease along the first direction a helps to ensure that the inlet 51 at the distal end of the guide portion 13 is coaxially arranged with the tube body 11, thereby ensuring the restraint of the guide portion 13 on the distal protection device 200.

[0094] Still Figure 14-18As shown, along the first direction a, the outer diameter change of the guide portion 13 per unit length gradually decreases. Optionally, the guide portion 13 is a hemispherical structure, which helps to reduce the damage to the blood vessel 2000 when the catheter 10 is pushed. At this time, the inlet 51 at the distal end of the guide portion 13 is larger than the outer diameter of the distal protection device 200, which helps to ensure the delivery effect of the guide wire assembly 60. Along the first direction a, both ends of the inlet 51 are provided with rounded corners, which form the above-mentioned guide surface 53 to ensure the rapid guidance of the guide wire assembly 60 by the guide portion 13, further improving the use effect of the delivery catheter 100.

[0095] It should be pointed out that the material of the guide portion 13 and the tube body 11 may be the same or different. At the same time, the inlet 51 of the guide portion 13 is the above-mentioned first inner diameter. At this time, the guide portion 13 has deformation ability, and when the protective umbrella assembly 80 passes through the inlet 51, the movement of the protective umbrella assembly 80 can drive the inlet 51 to expand along the radial direction of the tube body 11 and form a second inner diameter, thereby ensuring the transportation of the protective umbrella assembly 80.

[0096] In addition, the inlet 51 at the far end of the guide portion 13 is slightly larger than the outer diameters of the first developing ring 81 and the second developing ring 82. Slightly larger means that the outer diameter of the first developing ring 81 is 85%-95% of the minimum inner diameter (inlet 51) of the guide portion 13. Optionally, the outer diameter of the first developing ring 81 is 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95% of the inner diameter of the inlet 51. In this embodiment, the outer diameter of the first developing ring 81 is 85% of the inner diameter of the inlet 51.

[0097] In addition, the guide portion 13 may be configured as other shapes, such as a cone, in addition to being configured as a hemispherical structure. Moreover, the guide portion 13 may be configured as a combination of a plurality of guide bars, which structure is not shown in the figure, wherein the first ends of the plurality of guide bars are connected to the conduit 10, the second ends of the plurality of guide bars extend toward the axis of the conduit 10, and the second ends of the plurality of guide bars are bent to form a guide surface 53 to ensure that the first developing ring 81 can be recovered into the conduit 10.

[0098] It should be further understood that the guide portion 13 is a polymer part 50 and is a hemispherical structure. At the same time, a plurality of connecting holes 52 are provided on the guide portion 13, and the plurality of connecting holes 52 are arranged around the axis of the tube body 11. The arrangement of the connecting holes 52 enables the guide portion 13 to form a carved hollow structure. At this time, under the action of external force, the connecting holes 52 will deform, thereby causing the guide portion 13 to deform, and allowing the protective umbrella assembly 80 to pass through the inlet 51.

[0099] Specifically, when the guide portion 13 and the tube body 11 are an integrally formed part, a Tip head with a hollow structure is provided at the distal end of the catheter 10, the inner diameter of the Tip head is 0.12mm-0.22mm, the bending radius of the distal end of the Tip head is 0.4mm-0.6mm, and the curved portion is laser engraved with a hollow pattern. Optionally, the pattern shape is designed to be a polygon. Of course, in addition to this, the pattern shape can also be a quadrilateral, a pentagon, or other shape structures. This embodiment is described with a quadrilateral. The diamond-shaped hollow pattern structure helps to reduce the hardness of the Tip head.

[0100] During the recovery process, by pulling the protective umbrella assembly 80, the first developing ring 81 at the proximal end of the protective umbrella assembly 80 squeezes the Tip head, thereby deforming the Tip head, increasing the diameter of the Tip inlet 51, and allowing the protective umbrella assembly 80 to smoothly enter the catheter 10. At the same time, the Tip head is designed with an arc structure, that is, a rounded structure, which can play a guiding role during the withdrawal process, making it easier for the protective umbrella to enter the delivery catheter 100, thereby solving the problem of jamming caused by the delivery rod 61 and the delivery catheter 100 not being on the same center, avoiding repeated recovery operations during the operation, reducing the operation time, and reducing the intraoperative risks such as spasm of the blood vessel 2000 caused by excessive recovery. At the same time, when the protective umbrella assembly 80 is collected in the catheter 10, the Tip head is squeezed, and the four hollow holes become smaller, which can prevent the thrombus in the catheter 10 from flowing to the distal end of the blood vessel 2000 again, and effectively prevent the blockage of the distal blood vessel 2000 from causing a stroke.

[0101] The second aspect of the present invention further proposes a distal protection system 1000, which includes the delivery catheter 100 of the present invention. Compared with the prior art, the distal protection system 1000 of the present invention has the technical advantages of the delivery catheter 100, which will not be described in detail here.

[0102] The above is only a preferred specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any changes or substitutions that can be easily thought of by a person skilled in the art within the technical scope disclosed by the present invention should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the claims.

Claims

1. A delivery catheter for delivering a distal protection device, characterized in that: The delivery catheter comprises a tube body and a guide portion, wherein the guide portion is arranged at the distal end of the tube body, the guide portion has a delivery channel for the distal protection device to pass through, and a guide surface is arranged on the end surface of the guide portion away from the tube body; The delivery channel is coaxially arranged with the tube body, and has a switchable first state and a second state. In the first state, the delivery channel has a first inner diameter, and in the second state, the delivery channel has a second inner diameter. The first inner diameter is smaller than the second inner diameter and smaller than the inner diameter of the tube body.

2. The delivery catheter according to claim 1, characterized in that: Along the axial direction of the tube body, the guide portion has a first cavity and a second cavity arranged in sequence, the second cavity and the first cavity are connected to the tube body in sequence, the first cavity and the second cavity are coaxially arranged, and the inner diameter of the second cavity is smaller than the inner diameter of the first cavity, and the second cavity is formed with the first inner diameter and the second inner diameter.

3. The delivery catheter according to claim 2, characterized in that: The inner diameter of the second cavity gradually decreases and then gradually increases along a first direction, and the first direction is a direction from the proximal end of the tube body to the distal end of the tube body.

4. The delivery catheter according to claim 2, characterized in that: The guiding part has a third cavity, and the third cavity is arranged outside the second cavity.

5. The delivery catheter according to claim 4, characterized in that: The guide part comprises an outer layer mesh tube and an inner layer mesh tube, and the outer layer mesh tube and the inner layer mesh tube are connected to form the first cavity, the second cavity and the third cavity.

6. The delivery catheter according to claim 1, characterized in that: The guide part is a metal braided piece.

7. The delivery catheter according to claim 1, characterized in that: The guide portion and the tube body are integrally formed, the outer diameter of the guide portion gradually decreases along a first direction, the first direction is the direction from the proximal end of the tube body toward the distal end of the tube body, and the inner diameter of the guide portion is greater than the outer diameter of the distal protection device.

8. The delivery catheter according to claim 1, characterized in that: The guide part is a polymer part, and a plurality of communication holes are opened on the guide part. The plurality of communication holes are arranged around the axis of the tube body.

9. The delivery catheter according to any one of claims 1 to 8, characterized in that: A developing member is disposed at the distal end of the tube body, and along the axial direction of the tube body, the developing member is spaced apart from the guiding portion.

10. A remote protection system, characterized in that: The distal protection system comprises a delivery catheter according to any one of claims 1-9.

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