Pulmonary artery thrombus extraction device and thrombus removal system

Abstract

The invention relates to a pulmonary artery thrombus extraction device and a thrombus removing system. The pulmonary artery thrombus extraction device comprises a thrombus extraction support and a conveying catheter, and the thrombus extraction support is connected with a support tip; the stent tip is limited and exposed out of a far-end tube opening of the conveying catheter, a guide wire channel is formed in the stent tip, the guide wire channel comprises a tip inlet and a lateral outlet, and the stent tip comprises a conical tip or an eccentric bent tip. The stent tip is detachably connected to the distal end of the thrombectomy stent. The problem that an existing pulmonary artery thrombectomy stent conveying catheter is too large in outer diameter can be solved, guide wire cavities are not formed in the thrombectomy stent and the conveying catheter, and the outer diameter of the conveying catheter in the state that the thrombectomy stent is pressed in the conveying catheter in a lying mode is reduced; the thrombectomy stent and the conveying catheter can be conveyed to the farther part of the pulmonary artery or the pulmonary artery branch blood vessel, the thrombectomy stent can be conveniently released after penetrating through the thrombus, and the thrombus is prevented from escaping.

Description

Technical Field

[0001] The present application relates to the field of medical device technology, and in particular to a pulmonary artery thrombectomy device and a thrombus removal system. Background Art

[0002] Pulmonary embolism refers to a pathological and clinical condition caused by an impaction that enters the pulmonary artery and its branches, blocking the blood supply to the tissues. The most common emboli are blood clots, while others are rare neoplastic cells, fat droplets, air bubbles, intravenously injected drug particles, and even catheter tips that cause pulmonary vascular blockage.

[0003] Some patients with pulmonary embolism can dissolve on their own without treatment. However, studies have found that the mortality rate of patients with untreated pulmonary embolism is more than 20%. Conventional treatments for thrombosis are anticoagulation and thrombolysis, which do not achieve good therapeutic effects and have many limitations on the patient's condition.

[0004] There are very few thrombectomy devices used on the pulmonary artery now. The current medical treatment for pulmonary embolism is balloon dilatation, which mechanically dilates the narrowed or occluded pulmonary artery to improve the blood flow through it.

[0005] Among the publicly available pulmonary artery thrombectomy stents, most are delivery devices with a guidewire cavity, resulting in a larger diameter of the delivery device. The diameter of the delivery tube of the marketed product is 12F, which is punctured by the femoral vein, passes through the lower limb vein, right atrium and right ventricle to reach the pulmonary artery. The larger diameter directly affects the deliverability and increases the difficulty for the stent to reach the pulmonary artery embolism. Summary of the invention

[0006] The purpose of the present application is to provide a pulmonary artery thrombus removal device and a thrombus removal system, which can solve the problem of the existing pulmonary artery thrombus removal stent delivery catheter having an excessively large outer diameter. By not providing a guidewire cavity on the thrombus removal stent and the delivery catheter, the outer diameter of the delivery catheter when the thrombus removal stent is pressed inside the delivery catheter is reduced, and the thrombus removal stent and the delivery catheter can be delivered to a more distant part of the pulmonary artery or a branch vessel of the pulmonary artery, and the thrombus removal stent can be released after passing through the thrombus to prevent the thrombus from escaping.

[0007] In order to achieve the above-mentioned object, in a first aspect, the present invention provides a pulmonary artery thrombus removal device, comprising: a thrombus removal stent made of nickel-titanium alloy, and a delivery catheter, wherein the thrombus removal stent is connected to a stent tip;

[0008] The tip of the stent is limitedly exposed outside the distal tube opening of the delivery catheter, and the thrombus removal stent can be retracted forward and backward along the axial direction of the delivery catheter relative to the distal tube opening, so as to enable the thrombus removal stent to self-expand and release outside the distal tube opening, and elastically compress inside the distal tube opening;

[0009] The tip of the stent is provided with a guidewire channel, the guidewire channel comprising a tip inlet and a lateral outlet, the tip inlet is opened on the tip surface of the tip of the stent, and the lateral outlet is opened on the side wall of the tip of the stent, so as to enable the guidewire to be guided and extended outside the delivery catheter;

[0010] The stent tip comprises a conical tip, the conical tip is coaxially arranged with the thrombus removal stent, and the guidewire channel comprises a bent passage arranged on the conical tip;

[0011] Alternatively, the stent tip includes an eccentrically bent tip, the guidewire channel includes a straight path provided at the eccentrically bent portion, and the extension direction of the straight path is parallel to the axial direction of the thrombus removal stent;

[0012] The tip of the stent is detachably connected to the distal end of the thrombus removal stent, and the outer diameter of the proximal end of the tip of the stent is not less than the outer diameter of the distal end tube opening.

[0013] In an optional embodiment, the stent tip includes a flexible tip of a solid structure, the flexible tip is provided with a mounting portion, the mounting portion includes a connecting countersunk hole opened on the proximal surface of the flexible tip, the thrombus removal stent includes a distal connecting section, the distal connecting section elastically expands outward and is radially pressed in the connecting countersunk hole, the guide wire channel includes a through hole opened on the flexible tip, and at least a partially solid area is left between the through hole and the connecting countersunk hole.

[0014] In an optional embodiment, the tip inlet includes a circular hole arranged at the tip of the support, and the lateral outlet includes an elliptical hole arranged on the side wall of the tip of the support, and the elliptical hole includes at least a length.

[0015] In an optional embodiment, the curved passage on the conical tip includes a straight passage and an inclined passage, the extension direction of the straight passage coincides with the axis of the thrombectomy stent and the stent tip, the inclined passage extends directly to the lateral outlet with the same channel diameter as the straight passage or with a channel diameter larger than that of the straight passage, and the inclined passage extends obliquely from far to near relative to the axial direction of the stent tip.

[0016] In an optional embodiment, the proximal end of the thrombus removal stent is connected to a pushing guide wire, which is formed by braiding multiple strands of stainless steel wires. A fixing block, a twisting section, a spiral section and a connecting block are sequentially arranged along the length direction of the pushing guide wire from near to far, and the spiral section includes a hollow cavity located inside. The thrombus removal stent includes a proximal connecting section, and the proximal connecting section is connected and fixed to the connecting block via an adapter.

[0017] In an optional embodiment, the adapter includes a screw-on cone head, and a connecting column is provided at the distal end of the connecting block, and the connecting column is threadedly connected to the cone barrel section of the screw-on cone head;

[0018] The distal end of the threaded cone head is connected with a transfer sleeve, and the proximal connecting section passes through the transfer sleeve and extends into the straight section fixed on the threaded cone head.

[0019] In an optional embodiment, the delivery catheter comprises a single-lumen catheter, the tube wall of the single-lumen catheter comprises multiple layers of material, including a PEBAX material at an outer layer, a stainless steel braided wire at a middle layer, and a PTFE material at an inner layer;

[0020] The outer diameter of the delivery catheter is no more than 7F, a radiopaque marking ring is connected to the distal end of the delivery catheter, and a handle with a Luer connector is connected to the proximal end of the delivery catheter.

[0021] In an optional embodiment, the thrombus removal stent comprises a multi-section gourd shape in a released state, and is capable of cutting the thrombus in the pulmonary artery through the stent mesh after release.

[0022] In a second aspect, the present invention provides a pulmonary artery thrombus removal system, comprising an aspiration catheter, a dilator, a Y-type connector, and a pulmonary artery thrombus removal device according to any one of the aforementioned embodiments, wherein the distal end of the delivery catheter is inserted into the aspiration catheter and extends from the distal end of the aspiration catheter, and the proximal end of the delivery catheter is exposed at the proximal end of the aspiration catheter;

[0023] The Y-shaped connector is connected to the proximal end of the delivery catheter, and the thrombus removal stent enters the delivery catheter through the Y-shaped connector.

[0024] In an optional embodiment, the proximal end of the suction catheter is connected to a suction tube, and the suction tube is connected to an aspirator;

[0025] During use of the pulmonary artery thrombus removal system, the suction catheter and the dilator are assembled and transported to the thrombus location along the preset guide wire, and the dilator is removed after reaching the thrombus location;

[0026] The pulmonary artery thrombectomy device is delivered to the thrombus location along the guide wire in the aspiration catheter and the tip of the thrombectomy stent is passed through the thrombus;

[0027] Withdraw the delivery catheter to release the thrombectomy stent into the thrombus. Then, relative to the exposed release state of the thrombectomy stent and the delivery catheter, simultaneously withdraw the thrombectomy stent and the delivery stent to bring the thrombus into the suction catheter, and use the aspirator to perform negative pressure suction on the suction catheter to complete the removal of the pulmonary artery thrombus.

[0028] The pulmonary artery thrombectomy device of the present invention can form a straight-in and side-out guidewire on the tip of the stent by limiting the tip of the stent to be exposed outside the distal tube opening of the delivery catheter, and the guidewire channel on the tip of the stent is arranged between the tip of the stent and the side wall, thereby forming a lateral penetration of the guidewire, thereby avoiding the need to additionally set up a catheter cavity on the thrombectomy stent and the delivery catheter, and can reduce the diameter of the delivery catheter to the greatest extent, so that the delivery catheter with the thrombectomy stent elastically compressed on the inner side of the distal tube opening can smoothly pass through the blood vessel path to reach the designated position.

[0029] At the same time, compared with the tree-like structure of pulmonary arteries with more branches, a delivery catheter with a smaller diameter can not only smoothly pass the thrombectomy stent through the vascular path to the designated position, but also facilitate the delivery catheter and the tip of the stent to pass through the thrombus, and on the other hand, avoid the displacement of the thrombus. The thrombus at the designated location can be effectively cut by the self-expanding and released thrombectomy stent that reaches the designated position, which is conducive to subsequent suction and removal.

[0030] The different types of shape structures included in the stent tip can help reduce the delivery resistance of the thrombus removal stent when it is not released, or can make it easier for the stent tip to pass through the thrombus. Combined with the different forms of guidewire channels corresponding to the stent tips on different structures, the guidewire and the guidewire channel can be better coordinated, allowing the stent tip to be pushed more smoothly under the guidance of the guidewire.

[0031] By detachably connecting the tip of the stent to the distal end of the thrombectomy stent, it can be flexibly replaced according to different application conditions, thereby facilitating adjustment for different types of patient conditions.

[0032] The proximal outer diameter of the stent tip is not less than the outer diameter of the distal tube opening on the delivery catheter, which can form a necessary limiting relationship with the distal tube opening of the delivery catheter, so that the stent tip can only be limited to be exposed outside the delivery catheter and does not retract into the delivery catheter, thereby ensuring the effective cooperation between the stent tip and the guide wire outside the delivery catheter, and at the same time, the stent tip that is limited to be exposed at the distal tube opening can play a good open-circuit structure.

[0033] Other features and advantages of the present application will be described in detail in the subsequent specific implementation section. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present application and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without paying creative work.

[0035] Figure 1It is a schematic diagram of the overall structure of the pulmonary artery thrombectomy device and the Y-type connector;

[0036] Figure 2 is a schematic diagram of the structure of the thrombectomy stent;

[0037] Figure 3 is a schematic diagram of the structure of the delivery catheter;

[0038] Figure 4 It is a schematic diagram of the structure of a Y-type connector;

[0039] Figure 5 is a schematic diagram of the structure of the conical tip;

[0040] Figure 6 It is a schematic diagram of the structure of the eccentric bending tip;

[0041] Figure 7 A schematic diagram of the structure of the push guide wire;

[0042] Figure 8 It is a schematic diagram of the structure of the pulmonary artery thrombus removal system;

[0043] Fig. 9 It is a schematic diagram of the assembly structure of the suction catheter and the dilator;

[0044] Fig.10 A schematic diagram of the state structure for establishing an open circuit for the expander;

[0045] Fig.11 A schematic diagram of the structure of the state in which the expander is removed;

[0046] Fig.12 This is a schematic diagram of the structure of the stent tip passing through the thrombus;

[0047] Fig.13 This is a schematic diagram of the structure of the suction state after the thrombectomy stent is released.

[0048] icon:

[0049] 1-thrombectomy stent; 11-distal connecting segment; 12-proximal connecting segment;

[0050] 2- delivery catheter; 21- radiopaque marker ring; 22- handle; 23- Luer connector;

[0051] 3- support tip; 31- conical tip; 311- curved passage; 312- straight passage; 313- inclined passage;

[0052] 32-eccentrically bent tip;

[0053] 33-guidewire channel; 33a-tip inlet; 33b-lateral outlet; 34-connecting counterbore;

[0054] 4-push guide wire; 41-stainless steel wire; 42-fixing block; 43-screwing section; 44-spiral section; 45-connecting block; 45a-connecting column; 46-adapter; 46a-screw cone head; 46b-adapter sleeve;

[0055] 5-suction catheter; 51-suction tube;

[0056] 6- Dilator;

[0057] 7- Aspirator;

[0058] 8-Guide wire;

[0059] 9-Y-type connector. DETAILED DESCRIPTION

[0060] In order to make the purpose, technical scheme and advantages of the embodiments of the present application clearer, the technical scheme in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, rather than all of the embodiments. The components of the embodiments of the present application described and shown in the drawings here can be arranged and designed in various different configurations.

[0061] In the description of this application, it should be noted that the terms "inside", "outside", etc. indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, or the orientation or positional relationship in which the product of the application is usually placed when in use, which is only for the convenience of describing this application and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on this application. In addition, the terms "first", "second", etc. are only used to distinguish the description, and cannot be understood as indicating or implying relative importance.

[0062] In the description of this application, it should also be noted that, unless otherwise clearly specified and limited, the terms "disposed" and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a direct connection, or an indirect connection through an intermediate medium, or it can be the internal communication of two elements. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0063] See also Figure 1 , and combined with Figure 2-Figure 7The pulmonary artery thrombectomy device in the present application is mainly used for the treatment and removal of thrombi in pulmonary artery vessels. Specifically, by changing the connection form of the existing guide wire 8 in the thrombectomy stent 1 and the delivery catheter 2, the diameter of the delivery catheter 2 is reduced, so as to deliver the thrombectomy stent 1 and the delivery catheter 2 to the thrombus site in the pulmonary artery with more branches as much as possible, and the thrombus is cut by the in-situ release of the thrombectomy stent 1, and then aspiration and removal are performed.

[0064] By changing the guiding and connecting form of the guide wire 8 for the thrombus removal stent 1 and the delivery catheter 2, the penetration of the delivery catheter 2 in the pulmonary artery is improved to the greatest extent, and the thrombus removal stent 1 can be effectively and reliably delivered to the thrombus site.

[0065] See also Figure 1 The pulmonary artery thrombectomy device of the present invention has a main structure including a thrombectomy stent 1 made of nickel-titanium alloy and a delivery catheter 2 for delivering the thrombectomy stent 1. During the specific delivery process, the tip of the thrombectomy stent 1 is exposed from the delivery catheter 2, which is used to enhance the permeability of the stent-catheter complex formed by the thrombectomy stent 1 and the delivery catheter 2. The stent-catheter complex particularly refers to a combination of the thrombectomy stent 1 elastically compressed in the delivery catheter 2.

[0066] The stent tip 3 is connected to the thrombectomy stent 1. The stent tip 3 of the present invention is in a limited position and exposed to the distal end of the delivery catheter 2, whether the thrombectomy stent 1 is elastically compressed inside the delivery catheter 2 or relatively released outside the delivery catheter 2. In particular, when the thrombectomy stent 1 in the compressed state of the delivery catheter 2 is delivered to the distal end of the blood vessel, a good push open state can be established through the stent tip 3, thereby achieving the effect of reducing the push resistance.

[0067] The thrombectomy stent 1 can be extended and retracted forward and backward along the axial direction of the delivery catheter 2 relative to the distal tube opening of the delivery catheter 2, so as to enable the thrombectomy stent 1 to self-expand and release outside the distal tube opening, and elastically compress inside the distal tube opening.

[0068] Specifically, during the delivery of the stent-catheter combination, the thrombus removal stent 1 is elastically compressed on the inner side of the distal tube opening. When the stent-catheter combination is delivered to the thrombus site, especially when the stent tip 3 just passes through and reaches the distal side of the thrombus, the delivery catheter 2 is retracted relative to the thrombus removal stent 1, so that the thrombus removal stent 1 is extended relative to the distal tube opening of the delivery catheter 2, and the thrombus removal stent 1 is self-expanded and released at the thrombus site, and the thrombus is cut in situ while being released, thereby achieving the cutting process of the thrombus.

[0069] During conventional delivery, the thrombus removal stent 1 and the delivery catheter 2 are guided by the guidewire 8 passing through the internal guidewire cavity. Specifically, when the thrombus removal device is inserted into the blood vessel from outside the body, the tail end of the guidewire 8 exposed outside the body is passed through the guidewire cavity and extended from the proximal end of the thrombus removal device. Under the guidance of the guidewire 8, the thrombus removal device is extended into the blood vessel and reaches the predetermined target site.

[0070] However, the present application breaks through the conventional understanding. The guidewire 8 is not passed through the thrombectomy stent 1 and / or the delivery catheter 2, but is guided laterally through a lateral guidewire channel 33 provided on the stent tip 3. Combined with the above-mentioned form that the stent tip 3 is always exposed on the delivery catheter 2, the guidewire 8 is guided laterally and then passed outside the delivery catheter 2, thereby avoiding the need to provide a special guidewire cavity inside the delivery catheter 2 or on the thrombectomy stent 1, thereby greatly reducing the stent-catheter complex, especially the outer diameter of the delivery catheter 2, so that it can be more suitable for push transmission in pulmonary arteries with smaller sizes and more branches.

[0071] At the same time, from another perspective, although the existing thrombectomy stent 1 also has a partial guidewire-free lumen setting, it is more often used for thrombectomy in cranial arteries. Compared with the form of cranial artery with fewer branches, the pulmonary artery has a large number of branches. Without the guidance of the guidewire 8, the thrombectomy stent 1 can easily reach the designated position of the cranial artery, but this application scenario cannot be compared with the structural form of the pulmonary artery with more branches in the present application. Without the guidance of the guidewire 8, it is difficult for the thrombectomy stent 1 to reach the designated position of the pulmonary artery. In the existing conventional cognition, the guidewire-free lumen thrombectomy stent 1 of the cranial artery and the application of reaching the designated lesion site of the cranial artery without the guidance of the guidewire 8 cannot be linked to the structural form of the present application in which the guidewire 8 cooperates with the lateral guidewire channel 33 of the stent tip 3. Here is an explanation of the actual application angle.

[0072] The lateral guide wire channel 33 on the stent tip 3 of the present invention specifically includes a tip inlet 33a and a lateral outlet 33b. The tip inlet 33a referred to here is the reverse plug-in inlet of the tail end of the guide wire 8, and the tip inlet 33a is opened on the tip surface of the stent tip 3.

[0073] The lateral outlet 33b is the reverse connection outlet of the tail end of the guide wire 8. The lateral outlet 33b is opened on the side wall of the stent tip 3. Through this setting method, the ultimate goal is to combine the exposure of the stent tip 3 at the distal end of the delivery catheter 2 to enable the guide wire 8 to be guided and extended outside the delivery catheter 2.

[0074] It needs to be added again that most of the existing conventional pulmonary artery thrombectomy stents 1 are delivery catheters 2 with guidewire lumens, resulting in a larger diameter of the delivery catheter 2. The outer diameter of the delivery catheter 2 of the marketed product is 12F, which is punctured by the femoral vein, passes through the lower limb vein, right atrium and right ventricle to reach the pulmonary artery. The larger diameter directly affects the deliverability, which increases the difficulty for the thrombectomy stent 1 to reach the site of pulmonary embolism, i.e., pulmonary artery thrombosis.

[0075] By guiding the guide wire 8 to extend outside the delivery catheter 2, the outer diameter of the delivery catheter 2 is greatly reduced, and the outer diameter is controlled within 7F. The thrombus removal stent 1 can smoothly pass through the blood vessel path to reach the designated position. The reduction in the outer diameter of the delivery catheter 2 can facilitate the overall stent-catheter combination to pass through the thrombus, especially under the exposed open circuit effect of the stent tip 3, making it easier for the delivery catheter 2 to pass through the thrombus, while not causing the thrombus to shift, so that the relatively stable thrombus can be effectively cut and processed after the thrombus removal stent 1 is released.

[0076] The tip 3 of the stent in the present invention plays a substantial role in establishing an open circuit and penetrating a thrombus, and can be selected and set according to specific actual needs in different application scenarios.

[0077] Specifically, the stent tip 3 includes a commonly used conical tip 31, which is coaxially arranged with the thrombus removal stent 1, and the guidewire channel 33 includes a bent passage 311 arranged on the conical tip 31. Through this arrangement, the stent tip 3 can more easily pass through the thrombus, which is suitable for the treatment of larger pulmonary artery thrombi.

[0078] At the same time, the stent tip 3 also includes an eccentric bent tip 32, and the guidewire channel 33 includes a straight path set at the eccentric bent position, and the extension direction of the straight path is parallel to the axial direction of the thrombectomy stent 1. Obviously, the straight path of the eccentric bent tip 32 can reduce the resistance during transportation along the guidewire 8, and minimize the friction interference between the guidewire 8 and the stent tip 3. It is suitable for branch pulmonary arteries and can be more easily inserted and passed through curved blood vessels.

[0079] Regardless of the form, the guide wire 8 can be extended outside the delivery catheter 2 to achieve the technical purpose of reducing the outer diameter of the delivery catheter 2.

[0080] In order to better select different types of stent tips 3, the stent tip 3 is detachably connected to the distal end of the thrombectomy stent 1, and the proximal outer diameter of the stent tip 3 is not less than the outer diameter of the distal tube mouth, so that the stent tip 3 can be limited and exposed in the application of the distal tube mouth of the delivery catheter 2.

[0081] The stent tip 3 is detachably connected, which is also determined by the specific application scenario of the delivery catheter 2 and the thrombectomy stent 1 in this application. Specifically, when the stent-catheter combination reaches the thrombus site, especially when the stent tip 3 passes through the thrombus, the thrombectomy stent 1 does not move and is in the in-situ release state, while the delivery catheter 2 moves back relative to the thrombectomy stent 1 to avoid the relative release space.

[0082] After the thrombus removal stent 1 is released and completes the in-situ cutting of the thrombus, the thrombus removal stent 1 and the delivery catheter 2 are withdrawn together and synchronously, and enter the suction catheter 5 of the thrombus removal system synchronously. Therefore, since the delivery catheter 2 is not pushed forward relative to the thrombus removal stent 1, it is only necessary to consider the tight fit between the stent tip 3 and the thrombus removal stent 1. At the same time, since the stent body on the proximal side of the stent tip 3 has already released and cut the thrombus, the thrombus has been minimized. The resistance of the stent tip 3 to the withdrawal of the stent tip 3 is minimized. Therefore, the tight fit between the distal part of the thrombus removal stent 1 and the stent tip 3 can ensure the overall combination of the two, and fundamentally avoid the separation of the stent tip 3 and the thrombus removal stent 1.

[0083] In one specific embodiment, the stent tip 3 includes a flexible tip of a solid structure, which enables the stent tip 3 to bend in accordance with the curvature of the blood vessel, thereby enhancing the passing performance.

[0084] From the perspective of the connection and cooperation between the stent tip 3 and the thrombus removal stent 1, the flexible tip is provided with a mounting portion, which includes a connecting countersunk hole 34 opened on the proximal surface of the flexible tip. The thrombus removal stent 1 includes a distal connecting section 11. Since the thrombus removal stent 1 is made of nickel-titanium alloy and has a certain elasticity, the distal connecting section 11 can be elastically expanded and radially pressed in the connecting countersunk hole 34 to achieve a tight connection and cooperation between the two.

[0085] The guidewire channel 33 includes a through hole opened on the flexible tip, which can allow the guidewire 8 to pass through effectively. At the same time, the through hole can avoid friction interference of the guidewire 8 in the guidewire channel 33 through sufficient radial space, thereby preventing friction resistance between the guidewire 8 and the stent tip 3.

[0086] On the basis of the blood vessel permeability and thrombus permeability of the stent tip 3, at least a partially solid area is left between the through-hole and the connecting counterbore 34, which can form a certain solid structure, avoid affecting the structural strength of the stent tip 3 due to the opening of the through-hole, and prevent the stent tip 3 from bending when passing through the blood vessel and the thrombus.

[0087] In order to ensure that the guidewire 8 passes through the guidewire channel 33 effectively and to avoid friction between the guidewire 8 and the stent tip 3 to the greatest extent, it is necessary to consider the movable space of the guidewire channel 33 relative to the guidewire 8. Specifically, the tip inlet 33a includes a circular hole arranged at the stent tip 3, and the lateral outlet 33b includes an elliptical hole arranged on the side wall of the stent tip 3, and the elliptical hole includes at least a length. Through this arrangement, sufficient movable space can be provided for the guidewire 8 in the guidewire channel 33, thereby avoiding the risk of friction interference between the guidewire 8 and the stent tip 3.

[0088] The guiding of the guide wire 8 in the present application must fully consider the straight guiding state of the guide wire 8. At this angle, the straight path on the eccentric bent tip 32 can be better realized.

[0089] When the bent passage 311 on the conical tip 31 is in a state, the present application avoids the influence of the bent passage 311 on the insertion of the guide wire 8 by setting a necessary guide wire channel 33 structure.

[0090] Specifically, when the tip 3 of the stent is a conical tip 31, the bent passage 311 on the conical tip 31 includes a straight passage 312 and an inclined passage 313. On the basis that the tip 3 of the stent is coaxially arranged with the thrombus removal stent 1, the extension direction of the straight passage 312 coincides with the axis of the thrombus removal stent 1 and the tip 3 of the stent, which can promote the guide wire 8 to be inserted at an angle parallel to the axes of the two, thereby avoiding frictional contact interference of the guide wire 8 on the straight passage 312.

[0091] Most importantly, the inclined passage 313 is directly connected to the lateral outlet 33b with the same channel diameter as the straight passage 312, or more preferably, the inclined passage 313 is directly connected to the lateral outlet 33b with a channel diameter larger than that of the straight passage 312, so as to provide a larger amount of moving space for the guide wire 8 in the inclined passage 313, thereby minimizing the risk of frictional contact interference between the guide wire 8 and the stent tip 3 at the bending portion.

[0092] Furthermore, the inclined passage 313 is radially inclined and extended from far to near relative to the axial direction of the stent tip 3, so that the obtuse angle between the axis of the inclined passage 313 and the axis of the straight passage 312 is not less than 120°, thereby reducing the bending degree of the guide wire 8 in the bent passage 311 and reducing the risk of frictional contact interference between the guide wire 8, especially the bent part of the guide wire 8, and the stent tip 3.

[0093] In another specific embodiment, in order to facilitate the pushing and retraction control of the thrombus removal stent 1, the proximal end of the thrombus removal stent 1 is connected to a pushing guide wire 4, which is woven from multiple strands of stainless steel wires 41. Along the length direction of the pushing guide wire 4, a fixing block 42, a twisting section 43, a spiral section 44 and a connecting block 45 are sequentially arranged from near to far. The fixing block 42 is mainly used to fix the multiple strands of stainless steel wires 41, and is convenient for hand-held operation.

[0094] The twisting section 43 can maintain the twisted connection of multiple strands of stainless steel wires 41, which is conducive to the integration of different stainless steel wires 41. The spiral section 44 includes a hollow cavity located inside, which can enhance the overall flexibility of the pushing guide wire 4 and make it easier to perform bending-adaptive directional pushing.

[0095] The thrombus removal stent 1 includes a proximal connecting section 12 , which is fixedly connected to the connecting block 45 via an adapter 46 , and can control the forward and backward movement of the thrombus removal stent 1 by pushing and pulling the guide wire 4 forward and backward.

[0096] It should be pointed out that the thrombus removal stent 1 and the pushing guide wire 4 are fixedly connected to ensure the stability and reliability of the connection between the thrombus removal stent 1 and the pushing guide wire 4 .

[0097] On the basis of the above-mentioned description, the adapter 46 includes a screw-on cone head 46a, which includes a cone section located on the proximal side and a straight section located on the distal side. A connecting column 45a is fixedly provided at the distal end of the connecting block 45. The connecting column 45a is threadedly connected to the cone section of the screw-on cone head 46a to achieve the connection and fixation between the push guide wire 8 and the adapter 46.

[0098] From the connection angle between the thrombus removal bracket 1 and the adapter 46, the distal end of the screw-on cone head 46a is connected to the adapter sleeve 46b, and the proximal connecting section 12 of the thrombus removal bracket 1 passes through the adapter sleeve 46b and extends into the straight section fixed on the screw-on cone head 46a. Through this setting method, the proximal connecting section 12 can be fixedly installed on the adapter sleeve 46b and the screw-on cone head 46a, thereby ensuring the stability and reliability of the connection.

[0099] With this arrangement, the thrombus removal stent 1 can be reliably connected to the push guide wire 8 through the adapter 46 , thereby fundamentally preventing the thrombus removal stent 1 from being separated.

[0100] Based on the insertion of the thrombectomy stent 1 in the delivery catheter 2 and the ability for the thrombectomy stent 1 to telescopically move relative to the delivery catheter 2, the delivery catheter 2 in the present invention includes a single-lumen catheter and no additional guidewire lumen is provided.

[0101] The tube wall of the single-lumen catheter includes multiple layers of material, including PEBAX material in the outer layer, stainless steel braided wire in the middle layer and PTFE material in the inner layer, which ensures the passability of the delivery catheter 2 in the blood vessel through the outer layer, ensures the smoothness of the telescopic sliding of the thrombectomy stent 1 relative to the inner wall of the outer tube through the inner layer, and ensures the pushing performance of the outer tube as a whole in the blood vessel through the middle layer, while also taking into account the strength and flexibility of the overall structure.

[0102] Since there is no separate guidewire cavity, the outer diameter of the delivery catheter 2 is no more than 7F, and a radiopaque marker ring 21 is connected to the distal end of the delivery catheter 2, so that the positional relationship of the thrombectomy stent 1 relative to the distal end of the delivery catheter 2 can be examined, thereby ensuring accurate release of the thrombectomy stent 1. The proximal end of the delivery catheter 2 is connected to a handle 22 with a Luer connector 23, which can be easily pulled out.

[0103] From the perspective of facilitating the in-situ release of the thrombus retriever stent 1 so as to accurately cut the thrombus of the pulmonary artery embolism, since the thrombus retriever stent 1 is a nickel-titanium alloy with memory elasticity, the thrombus retriever stent 1 in the present invention includes a multi-section gourd shape in the released state. After the tip 3 of the stent passes through the mass thrombus, the thrombus can be divided into the annular waist groove between the multi-section gourd segments after the thrombus retriever stent 1 is released, and then combined with the overall withdrawal of the pulmonary artery thrombus retriever device, the thrombus is brought into the suction catheter 5 of the removal system and removed from the blood vessel under the action of the suction negative pressure.

[0104] It is important to point out that, in addition to having a certain degree of permeability, the thrombus removal stent 1 can also impart a certain fixation function to the thrombus through its in situ release, thereby effectively preventing the thrombus from escaping.

[0105] See also Figure 8 , and combined with Figure 9-13 The present invention also provides a pulmonary artery thrombus removal system, including a suction catheter 5, a dilator 6, a Y-type connector 9 and the above-mentioned pulmonary artery thrombus removal device. The distal end of the delivery catheter 2 is inserted into the suction catheter 5 and extends out from the distal end of the suction catheter 5. Furthermore, the delivery catheter 2 is movably inserted in the suction catheter 5, so that the delivery catheter 2 can drive the thrombus removal stent 1 to reach the distal end of the thrombus, and can enable the thrombus removal stent 1 and the delivery catheter 2 to have a relatively wide and flexible expansion space.

[0106] The proximal end of the delivery catheter 2 is exposed at the proximal end of the suction catheter 5, so that the delivery catheter 2 can be pushed and pulled flexibly and conveniently, and different working conditions can be accurately controlled.

[0107] The Y-shaped connector 9 is connected to the proximal end of the delivery catheter 2 , and the thrombus removal stent 1 enters the lumen of the delivery catheter 2 through the Y-shaped connector 9 .

[0108] The proximal end of the suction catheter 5 is connected to a suction tube 51 , and the suction tube 51 is connected to an aspirator 7 . Through the setting of the aspirator 7 , a suction operation can be performed to establish a stable and reliable suction negative pressure for the suction catheter 5 .

[0109] The pulmonary artery thrombus removal system includes the following steps during use:

[0110] After the suction catheter 5 and the dilator 6 are assembled, they are transported to the location of the thrombus along the preset guide wire 8. Under the guidance of the guide wire 8, the dilator 6 can accurately reach the location of the thrombus, and then the dilator 6 is taken out to obtain a good expansion pathway. When the dilator 6 establishes the pathway, the distal end of the dilator 6 does not pass through the thrombus, and stays on the proximal side of the thrombus, indicating that the circuit is opened, and then the dilator 6 is withdrawn.

[0111] The tail end of the guide wire 8 is passed through the guide wire channel 33 of the stent tip 3, and the stent-catheter partner of the pulmonary artery thrombectomy device is transported to the thrombus location along the guide wire 8 in the suction catheter 5, and the stent tip 3 of the thrombectomy stent 1 is passed through the thrombus, completing the penetration of the thrombus and fixing the thrombus from another angle.

[0112] The delivery catheter 2 is withdrawn to release the thrombus removal stent 1 in situ in the thrombus, so that the thrombus removal stent 1 cuts the thrombus in situ, and then the thrombus removal stent 1 and the delivery stent are withdrawn synchronously relative to the exposed release state of the thrombus removal stent 1 and the delivery catheter 2, so that the thrombus removal stent 1 is elastically compressed at the distal end of the suction catheter 5. Since the diameter of the suction catheter 5 is larger than the diameter of the delivery catheter 2, the elastic compression amount is much smaller than the elastic compression amount when it is compressed in the delivery catheter 2. Therefore, the thrombus can be cut and intercepted in a smaller compression deformation state, and the cut and intercepted thrombus is brought into the suction catheter 5 at the same time. The suction catheter 5 is suctioned under negative pressure in combination with the suction device 7, so that the cut small-sized thrombus is collected into the suction device 7 through the suction catheter 5, and the removal of the pulmonary artery thrombus is completed.

[0113] The pulmonary artery thrombus removal system of the present invention can fundamentally ensure the effect of removing thrombi in pulmonary artery vessels, and provide technical guarantee for timely and reliable treatment of pulmonary embolism.

[0114] It should be noted that, in the absence of conflict, the features in the embodiments of this application may be combined with each other.

[0115] The above description is only the preferred embodiment of the present application and is not intended to limit the present application. For those skilled in the art, the present application may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A pulmonary artery thrombectomy device, It is characterized in that include: A thrombectomy stent made of nickel-titanium alloy, and a delivery catheter, wherein the thrombectomy stent is connected to a stent tip; The tip of the stent is limitedly exposed outside the distal tube opening of the delivery catheter, and the thrombus removal stent can be retracted forward and backward along the axial direction of the delivery catheter relative to the distal tube opening, so as to enable the thrombus removal stent to self-expand and release outside the distal tube opening, and elastically compress inside the distal tube opening; The tip of the stent is provided with a guidewire channel, the guidewire channel comprising a tip inlet and a lateral outlet, the tip inlet is opened on the tip surface of the tip of the stent, and the lateral outlet is opened on the side wall of the tip of the stent, so as to enable the guidewire to be guided and extended outside the delivery catheter; The stent tip comprises a conical tip, the conical tip is coaxially arranged with the thrombus removal stent, and the guidewire channel comprises a bent passage arranged on the conical tip; Alternatively, the stent tip includes an eccentrically bent tip, the guidewire channel includes a straight path provided at the eccentrically bent portion, and the extension direction of the straight path is parallel to the axial direction of the thrombus removal stent; The tip of the stent is detachably connected to the distal end of the thrombus removal stent, and the outer diameter of the proximal end of the tip of the stent is not less than the outer diameter of the distal end tube opening.

2. The pulmonary artery thrombectomy device according to claim 1, It is characterized in that The tip of the stent includes a flexible tip of a solid structure, the flexible tip is provided with a mounting portion, the mounting portion includes a connecting countersunk hole opened on the proximal surface of the flexible tip, the thrombus removal stent includes a distal connecting section, the distal connecting section elastically expands outward and is radially pressed in the connecting countersunk hole, the guide wire channel includes a through hole opened on the flexible tip, and at least a partial solid area is left between the through hole and the connecting countersunk hole.

3. The pulmonary artery thrombectomy device according to claim 1, It is characterized in that The tip inlet comprises a circular hole arranged at the tip of the support, and the lateral outlet comprises an elliptical hole arranged on the side wall of the tip of the support, and the elliptical hole comprises at least a length.

4. The pulmonary artery thrombectomy device according to claim 1, It is characterized in that The curved passage on the conical tip includes a straight passage and an inclined passage, the extension direction of the straight passage coincides with the axis of the thrombus removal bracket and the bracket tip, the inclined passage extends directly to the lateral outlet with the same channel diameter as the straight passage or with a channel diameter larger than that of the straight passage, and the inclined passage extends obliquely from far to near relative to the axial direction of the bracket tip.

5. The pulmonary artery thrombectomy device according to claim 1, It is characterized in that The proximal end of the thrombus removal bracket is connected to a pushing guide wire, which is woven from multiple strands of stainless steel wire. A fixing block, a twisting section, a spiral section and a connecting block are sequentially arranged along the length direction of the pushing guide wire from near to far, and the spiral section includes a hollow cavity located inside. The thrombus removal bracket includes a proximal connecting section, and the proximal connecting section is connected and fixed to the connecting block via an adapter.

6. The pulmonary artery thrombectomy device according to claim 5, It is characterized in that The adapter comprises a screw-on cone head, a connecting column is provided at the distal end of the connecting block, and the connecting column is threadedly connected to the cone barrel section of the screw-on cone head; The distal end of the threaded cone head is connected with a transfer sleeve, and the proximal connecting section passes through the transfer sleeve and extends into the straight section fixed on the threaded cone head.

7. The pulmonary artery thrombectomy device according to claim 1, It is characterized in that The delivery catheter comprises a single-lumen catheter, the tube wall of which comprises multiple layers of material, including a PEBAX material at an outer layer, a stainless steel braided wire at a middle layer, and a PTFE material at an inner layer; The outer diameter of the delivery catheter is no more than 7F, a radiopaque marking ring is connected to the distal end of the delivery catheter, and a handle with a Luer connector is connected to the proximal end of the delivery catheter.

8. The pulmonary artery thrombectomy device according to claim 1, It is characterized in that The thrombus removal stent comprises a multi-section gourd shape in the released state, and can cut the thrombus in the pulmonary artery through the stent mesh after release.

9. A pulmonary artery thrombus removal system, It is characterized in that The device comprises a suction catheter, a dilator, a Y-type connector, and a pulmonary artery thrombectomy device according to any one of claims 1 to 8, wherein the distal end of the delivery catheter is inserted into the suction catheter and extends from the distal end of the suction catheter, and the proximal end of the delivery catheter is exposed at the proximal end of the suction catheter; The Y-shaped connector is connected to the proximal end of the delivery catheter, and the thrombus removal stent enters the delivery catheter through the Y-shaped connector.

10. The pulmonary artery thrombus removal system according to claim 9, It is characterized in that The proximal end of the suction catheter is connected to a suction tube, and the suction tube is connected to a suction device; During use of the pulmonary artery thrombus removal system, the suction catheter and the dilator are assembled and transported to the thrombus location along the preset guide wire, and the dilator is removed after reaching the thrombus location; The pulmonary artery thrombectomy device is delivered to the thrombus location along the guide wire in the aspiration catheter and the tip of the thrombectomy stent is passed through the thrombus; Withdraw the delivery catheter to release the thrombectomy stent into the thrombus. Then, relative to the exposed release state of the thrombectomy stent and the delivery catheter, simultaneously withdraw the thrombectomy stent and the delivery stent to bring the thrombus into the suction catheter, and use the aspirator to perform negative pressure suction on the suction catheter to complete the removal of the pulmonary artery thrombus.

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