A pulmonary artery thrombectomy device and a thrombus removal system

Abstract

This application relates to a pulmonary artery thrombectomy device and a thrombus removal system, including: a thrombectomy stent and a delivery catheter. The thrombectomy stent is connected with a stent tip; the stent tip is limited and exposed at the distal orifice of the delivery catheter. A guide wire channel is provided on the stent tip. The guide wire channel includes a tip inlet and a lateral outlet. The stent tip includes a conical tip, or the stent tip includes an eccentric bent tip. The stent tip is detachably connected to the distal end of the thrombectomy stent. The present invention can solve the problem that the outer diameter of the delivery catheter of the existing pulmonary artery thrombectomy stent is too large. By not providing a guide wire cavity on the thrombectomy stent and the delivery catheter, the outer diameter of the delivery catheter in the state where the thrombectomy stent is pressed and lying in the delivery catheter is reduced, and the thrombectomy stent and the delivery catheter can be delivered to a farther part of the pulmonary artery or the pulmonary artery branch vessel, and it is convenient to release the thrombectomy stent after passing through the thrombus, avoiding thrombus escape.

Description

Technical Field

[0001] The present application relates to the technical field of medical devices, and more specifically, to a pulmonary artery thrombectomy device and a thrombus removal system. Background Art

[0002] Pulmonary embolism refers to the pathological and clinical conditions caused by the embolus entering the pulmonary artery and its branches and blocking the blood supply of tissues. The common embolus is a thrombus, and the rest are rare neoplastic cells, fat droplets, air bubbles, drug particles input through veins, or even the pulmonary vascular blockage caused by the tip of a catheter.

[0003] Some patients with pulmonary embolism can dissolve on their own without treatment. However, studies have found that the mortality rate of patients with pulmonary embolism without treatment will exceed 20%. The conventional treatment methods for thromboembolism are anticoagulant therapy and thrombolytic therapy. These methods cannot achieve good treatment effects and have many restrictions on the patient's condition.

[0004] Currently, there are few thrombectomy devices used in the pulmonary artery. The current treatment method for pulmonary artery embolism is balloon dilation, which mechanically dilates the stenotic or occlusive pulmonary artery to improve the patency of blood flow passing through this area.

[0005] In the publicly available pulmonary artery thrombectomy stents, generally, they are all delivery devices with a guide wire lumen, resulting in a relatively large diameter of the delivery device. The diameter of the delivery tube of the marketed product is 12F. It is punctured through the femoral vein, passes through the lower limb veins, the right atrium, and the right ventricle to reach the pulmonary artery. The relatively large diameter directly affects the deliverability and increases the difficulty for the stent to reach the pulmonary artery embolism site. Summary of the Invention

[0006] The purpose of the present application is to provide a pulmonary artery thrombectomy device and a thrombus removal system, which can solve the problem of the too large outer diameter of the delivery catheter of the existing pulmonary artery thrombectomy stent. By not setting a guide wire lumen on the thrombectomy stent and the delivery catheter, the outer diameter of the delivery catheter in the state where the thrombectomy stent is compressed in the delivery catheter is reduced, enabling the thrombectomy stent and the delivery catheter to be delivered to a farther part of the pulmonary artery or the pulmonary artery branch vessel, and facilitating the release of the thrombectomy stent after passing through the thrombus to avoid thrombus escape.

[0007] To achieve the above purpose, in a first aspect, the present invention provides a pulmonary artery thrombectomy device, including: a thrombectomy stent made of nitinol alloy, and a delivery catheter, wherein the thrombectomy stent is connected with a stent tip;

[0008] The stent tip is limited and exposed outside the distal orifice of the delivery catheter. The thrombectomy stent can axially extend and retract relative to the distal orifice along the delivery catheter, so as to enable the thrombectomy stent to self-expand and release outside the distal orifice, and be elastically compressed inside the distal orifice;

[0009] A guide wire channel is provided on the tip of the stent. The guide wire channel includes a tip inlet and a lateral outlet. The tip inlet is opened on the tip surface of the stent tip, and the lateral outlet is opened on the side wall of the stent tip, so that the guide wire can be guided and extended outside the delivery catheter.

[0010] The stent tip includes a conical tip, and the conical tip is coaxially arranged with the thrombectomy stent. The guide wire channel includes a bent passage provided on the conical tip.

[0011] Alternatively, the stent tip includes an eccentric bent tip, the guide wire channel includes a straight passage provided at the eccentric bent portion, and the extending direction of the straight passage is parallel to the axial direction of the thrombectomy stent.

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

[0013] In an alternative embodiment, the stent tip includes a flexible tip with a solid structure. The flexible tip is provided with a mounting portion. The mounting portion includes a connecting counterbore opened on the proximal surface of the flexible tip. The thrombectomy stent includes a distal connecting section. The distal connecting section elastically expands outward and radially presses in the connecting counterbore. The guide wire channel includes a through hole opened on the flexible tip, and there is at least a partial solid region between the through hole and the connecting counterbore.

[0014] In an alternative embodiment, the tip inlet includes a circular hole provided on the stent tip, and the lateral outlet includes an elliptical hole provided on the side wall of the stent tip. The elliptical hole includes at least a section of length.

[0015] In an alternative embodiment, the bent passage on the conical tip includes a straight passage and an inclined passage. The extending direction of the straight passage coincides with the axis of the thrombectomy stent and the stent tip. The inclined passage leads directly to the lateral outlet with the same hole diameter as the straight passage or a hole diameter larger than that of the straight passage, and the inclined passage extends obliquely outward from far to near relative to the axial direction of the stent tip.

[0016] In an alternative embodiment, a pushing guide wire is connected to the proximal end of the thrombectomy stent. The pushing guide wire is woven by multiple strands of stainless steel wires. Along the length direction of the pushing guide wire, a fixing block, a screwing section, a spiral section, and a connecting block are sequentially arranged from near to far. The spiral section includes a hollow cavity inside. The thrombectomy stent includes a proximal connecting section, and the proximal connecting section and the connecting block are fixedly connected through a connector.

[0017] In an alternative embodiment, the adapter includes a screwed taper head, a connecting column is provided at the distal end of the connecting block, and the connecting column is threadedly connected to the tapered barrel section of the screwed taper head;

[0018] The distal end of the screwed taper head is connected with an adapter sleeve, and the proximal connecting section passes through the adapter sleeve and extends into the straight barrel section fixed to the screwed taper head.

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

[0020] The outer diameter of the delivery catheter is not greater than 7F, a radiopaque marker 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 alternative embodiment, the thrombectomy stent in the released state comprises multiple sections in a gourd shape, and can cut 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-shaped connector, and the pulmonary artery thrombectomy device according to any one of the foregoing embodiments. The distal end of the delivery catheter is inserted into the aspiration catheter and extends out from the distal end of the aspiration catheter, and the proximal end of the delivery catheter is exposed outside the proximal end of the aspiration catheter;

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

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

[0025] During the use of the pulmonary artery thrombus removal system, the aspiration catheter and the dilator are assembled and then delivered to the thrombus position along a pre-set guide wire. After reaching the thrombus position, the dilator is removed;

[0026] The pulmonary artery thrombectomy device is delivered to the thrombus position along the inner guide wire of the aspiration catheter, and the stent tip of the thrombectomy stent penetrates through the thrombus;

[0027] The delivery catheter is retracted, the thrombectomy stent is released in the thrombus, and then, relative to the exposed release state relationship of the thrombectomy stent to the delivery catheter, the thrombectomy stent and the delivery stent are synchronously retracted, bringing the thrombus into the aspiration catheter, and the aspiration catheter is negatively aspirated by the suction device to complete the removal of the pulmonary artery thrombus.

[0028] In the pulmonary artery thrombectomy device of the present invention, by limiting the exposure of the stent tip outside the distal orifice of the delivery catheter and arranging the guide wire channel on the stent tip between the tip and the side wall of the stent tip, a straight-in and side-out of the guide wire on the stent tip can be formed, thereby constituting a lateral penetration of the guide wire, and further avoiding the additional setting of a catheter lumen on the thrombectomy stent and the delivery catheter. The diameter of the delivery catheter can be reduced to the greatest extent, enabling the thrombectomy stent elastically compressed inside the distal orifice of the delivery catheter to smoothly pass through the vascular path to the designated position.

[0029] Meanwhile, compared with the pulmonary artery vessels with a more branched tree-like structure, on the basis that the delivery catheter with a smaller diameter can smoothly pass the thrombectomy stent through the vascular path to the designated position, on the one hand, it is beneficial for the delivery catheter and the stent tip to penetrate through the thrombus, and on the other hand, it can avoid thrombus displacement. The thrombectomy stent after self-expansion release reaching the designated position can effectively cut the thrombus at the designated site, facilitating subsequent aspiration and removal.

[0030] The different types of shape structures included in the stent tip can help reduce the delivery resistance of the thrombectomy stent when not released, or enable the stent tip to more easily penetrate through the thrombus. Combined with the different forms of guide wire channels corresponding to the stent tips on different structures, it can better match the guide wire with the guide wire channel, enabling the stent tip to be pushed more smoothly under the guiding action of the guide wire.

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

[0032] The outer diameter of the proximal contour of the stent tip is not less than the outer diameter of the contour of the distal orifice on the delivery catheter, which can form a necessary limiting relationship for the distal orifice of the delivery catheter, enabling the stent tip to be only limited and exposed outside the delivery catheter without retracting into the delivery catheter. Furthermore, it can ensure the effective cooperation between the stent tip and the guide wire outside the delivery catheter, and at the same time, the stent tip limited and exposed at the distal orifice can play a good opening 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 some embodiments of the present application, and therefore should not be regarded as limiting the scope. For those of ordinary skill in the art, other related drawings can be obtained based on these drawings without creative efforts.

[0035] Figure 1Schematic diagram of the overall structure of a pulmonary artery thrombectomy device and a Y-shaped connector;

[0036] Figure 2 Schematic diagram of the structure of the thrombectomy stent;

[0037] Figure 3 Schematic diagram of the structure of the delivery catheter;

[0038] Figure 4 Schematic diagram of the structure of the Y-shaped connector;

[0039] Figure 5 Schematic diagram of the structure of the conical tip;

[0040] Figure 6 Schematic diagram of the structure of the eccentrically bent tip;

[0041] Figure 7 Schematic diagram of the structure of the push wire;

[0042] Figure 8 Schematic diagram of the structure of the pulmonary artery thrombus removal system;

[0043] Figure 9 Schematic diagram of the assembled structure of the aspiration catheter and the dilator;

[0044] Figure 10 Schematic diagram of the state where the dilator creates an open path;

[0045] Figure 11 Schematic diagram of the state where the dilator is removed;

[0046] Figure 12 Schematic diagram of the state where the stent tip passes through the thrombus;

[0047] Figure 13 Schematic diagram of the state where aspiration is performed after the thrombectomy stent is released.

[0048] Icon:

[0049] 1 - Thrombectomy stent; 11 - Distal connection segment; 12 - Proximal connection segment;

[0050] 2 - Delivery catheter; 21 - Radiopaque marker ring; 22 - Handle; 23 - Luer connector;

[0051] 3 - Stent tip; 31 - Conical tip; 311 - Bent passage; 312 - Straight passage; 313 - Tapered passage;

[0052] 32 - Eccentrically bent tip;

[0053] 33 - Wire channel; 33a - Tip inlet; 33b - Lateral outlet; 34 - Connecting counterbore;

[0054] 4 - Pushing guide wire; 41 - Stainless steel wire; 42 - Fixed block; 43 - Screwing section; 44 - Spiral section; 45 - Connecting block; 45a - Connecting column; 46 - Adapter; 46a - Threaded taper head; 46b - Adapter sleeve;

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

[0056] 6 - Dilator;

[0057] 7 - Suction device;

[0058] 8 - Guide wire;

[0059] 9 - Y - type connector. Detailed implementation mode

[0060] To make the objectives, technical solutions and advantages of the embodiments of this application clearer, the technical solutions in the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings in the embodiments of this application. Obviously, the described embodiments are part of the embodiments of this application, rather than all of them. Usually, the components of the embodiments of this application described and illustrated in the accompanying drawings here can be arranged and designed in various different configurations.

[0061] In the description of this application, it should be noted that the orientation or positional relationship indicated by terms such as "inner", "outer", etc. is based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship in which the product of this application is usually placed when in use. It is only for the convenience of describing this application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation to this application. In addition, terms such as "first", "second", etc. are only used for descriptive distinction 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 "set", "connect" 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 directly connected, or indirectly connected through an intermediate medium, and it can be the communication inside two elements. For those of ordinary skill in the art, the specific meanings of the above terms in this application can be understood according to specific situations.

[0063] See Figure 1 and in combination with Figures 2 - 7, the pulmonary artery thrombectomy device in the present application is mainly used for the treatment and removal of thrombi in the pulmonary artery blood vessels. Specifically, by changing the threading 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 transport the thrombectomy stent 1 and the delivery catheter 2 to the thrombus site in the pulmonary artery blood vessels with more branches as much as possible, and the thrombus is cut by the in-situ release of the thrombectomy stent 1, and subsequent aspiration and removal are carried out.

[0064] By changing the guiding and threading form of the guide wire 8 for the thrombectomy stent 1 and the delivery catheter 2, the penetrability of the delivery catheter 2 in the pulmonary artery blood vessels is maximally improved, and the thrombectomy stent 1 can be effectively and reliably transported to the thrombus site.

[0065] See Figure 1 , the main structure of the pulmonary artery thrombectomy device in the present invention includes a thrombectomy stent 1 made of nitinol alloy and a delivery catheter 2 for transporting the thrombectomy stent 1. During the specific transportation process, the tip of the thrombectomy stent 1 is exposed outside the delivery catheter 2 to enhance the penetrability of the stent catheter combination formed by the thrombectomy stent 1 and the delivery catheter 2. The stent catheter combination especially refers to the combination when the thrombectomy stent 1 is elastically compressed in the delivery catheter 2.

[0066] A stent tip 3 is connected to the thrombectomy stent 1. In the present invention, whether the thrombectomy stent 1 is elastically compressed inside the delivery catheter 2 or the thrombectomy stent 1 is relatively released outside the delivery catheter 2, the stent tip 3 is in a state of being limited and exposed outside the distal orifice of the delivery catheter 2. Especially during the process of transporting the thrombectomy stent 1 in the compressed state of the delivery catheter 2 to the distal end of the blood vessel, a good pushing and opening state can be established through the stent tip 3, achieving the effect of reducing the pushing resistance.

[0067] The thrombectomy stent 1 can axially move back and forth along the distal orifice of the delivery catheter 2 relative to the delivery catheter 2, so that the thrombectomy stent 1 can be self-expanded and released outside the distal orifice and elastically compressed inside the distal orifice.

[0068] Specifically, during the transportation of the stent catheter combination, the thrombectomy stent 1 is elastically compressed inside the distal orifice. When the stent catheter combination is transported to the thrombus site, especially when the stent tip 3 just passes through and reaches the distal side of the thrombus, by the retraction movement of the delivery catheter 2 relative to the thrombectomy stent 1, the thrombectomy stent 1 extends relative to the distal orifice of the delivery catheter 2, and the thrombectomy stent 1 is self-expanded and released at the thrombus site, and the thrombus is cut in-situ during the release, so as to realize the cutting treatment of the thrombus.

[0069] During the conventional delivery process, the thrombectomy stent 1 and the delivery catheter 2 are guided by a guide wire 8 passing through the internal guide wire lumen thereof. Specifically, when the thrombectomy device is inserted into the blood vessel from outside the body, the distal end of the guide wire 8 exposed outside the body is inserted into the guide wire lumen and extends from the proximal end of the thrombectomy device. Under the guiding action of the guide wire 8, the thrombectomy device is inserted into the blood vessel and reaches the predetermined target site.

[0070] However, in this application, the conventional cognition is broken through. The guide wire 8 does not pass through the thrombectomy stent 1 and / or the delivery catheter 2, but through a lateral guide wire channel 33 provided on the stent tip 3, and combined with the form that the stent tip 3 is always exposed outside the delivery catheter 2 as described above, the guide wire 8 is guided laterally, and then the guide wire 8 is threaded outside the delivery catheter 2, thus avoiding the need to provide a dedicated guide wire lumen inside the delivery catheter 2 or on the thrombectomy stent 1, and thus significantly reducing the outer diameter of the stent catheter assembly, especially significantly reducing the outer diameter of the delivery catheter 2, so that it can be more suitable for pushing and transmitting in the pulmonary artery with smaller size and more branches.

[0071] At the same time, from another perspective, although there is also a partial setting without a guide wire lumen in the existing thrombectomy stent 1, it is more applied to thrombectomy in the cranial artery. Compared with the form of fewer branches in the cranial artery, the number of branches in the pulmonary artery is extremely large. In the state without the guidance of the guide wire 8, the thrombectomy stent 1 can easily reach the designated site in the cranial artery. However, this application scenario cannot be compared with the structural form of more branches in the pulmonary artery in this application. Without the guiding effect of the guide wire 8, it is very difficult for the thrombectomy stent 1 to reach the designated position in the pulmonary artery. In the existing conventional cognition, the application of the cranial artery thrombectomy stent 1 without a guide wire lumen and directly reaching the designated lesion site in the cranial artery without the guidance of the guide wire 8 cannot be associated with the structural form of the cooperation between the guide wire 8 and the lateral guide wire channel 33 of the stent tip 3 in this application. Here, a description from the perspective of practical application is made.

[0072] The lateral guide wire channel 33 on the stent tip 3 in 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 for the distal 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 threading outlet for the distal end of the guide wire 8, and 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 orifice of the delivery catheter 2, so as to enable the guide wire 8 to be guided and extended outside the delivery catheter 2.

[0074] It should be supplemented again that for the existing conventional pulmonary artery thrombectomy stents 1, most of them are delivery catheters 2 with wire lumens, resulting in a relatively large diameter of the delivery catheter 2. The outer diameter of the delivery catheter 2 of the commercially available products is 12F. It is punctured from the femoral vein, passes through the lower limb veins, the right atrium and the right ventricle to reach the pulmonary artery. The relatively large diameter directly affects the deliverability and increases the difficulty for the thrombectomy stent 1 to reach the pulmonary artery embolism site, that is, the pulmonary artery thrombus site.

[0075] By guiding and extending the guide wire 8 outside the delivery catheter 2, the outer diameter of the delivery catheter 2 is greatly reduced and controlled within 7F. This enables the thrombectomy stent 1 to smoothly pass through the vascular path to the designated position. The reduction of the outer diameter of the delivery catheter 2 is beneficial for the overall stent catheter assembly to pass through the thrombus. Especially under the open-circuit effect of the exposed stent tip 3, it makes the delivery catheter 2 easier to pass through the thrombus without causing thrombus displacement, so that the relatively stable thrombus can be effectively cut and processed immediately after the thrombectomy stent 1 is released.

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

[0077] Specifically, the stent tip 3 includes a common conical tip 31. The conical tip 31 is coaxially arranged with the thrombectomy stent 1. The guide wire channel 33 includes a bent path 311 arranged on the conical tip 31. Through this setting method, the stent tip 3 can more easily pass through the thrombus and is suitable for the treatment of relatively large-sized pulmonary artery thrombi.

[0078] At the same time, the stent tip 3 also includes an eccentric bent tip 32. The guide wire channel 33 includes a straight path arranged at the eccentric bent part, and the extending direction of the straight path is parallel to the axis of the thrombectomy stent 1. Obviously, the straight path of the eccentric bent tip 32 can reduce the resistance during the delivery along the guide wire 8 and minimize the frictional interference between the guide wire 8 and the stent tip 3. It is suitable for the branch pulmonary artery and is more likely to penetrate and pass through in the curved blood vessels.

[0079] No matter in what form, it can make the guide wire 8 extend 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 outer diameter of the proximal contour of the stent tip 3 is not less than the contour outer diameter of the distal end orifice, which can achieve the application that the stent tip 3 is limited and exposed at the distal end orifice 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 assembly reaches the thrombus site, especially after 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 backward relative to the thrombectomy stent 1 to avoid the relative release space.

[0082] When the thrombectomy stent 1 is released and the in-situ cutting of the thrombus is completed, the thrombectomy stent 1 and the delivery catheter 2 are retracted together and synchronously so that they enter the aspiration catheter 5 of the thrombus removal system synchronously. Therefore, since the delivery catheter 2 does not push forward relative to the thrombectomy stent 1, only the tight fit degree between the stent tip 3 and the thrombectomy stent 1 needs to be considered. At the same time, since the proximal side stent body of the stent tip 3 has already released and cut the thrombus, the resistance of the thrombus to the retraction of the stent tip 3 is reduced to the lowest level. Therefore, the overall combination of the two can be ensured through the tight fit between the distal part of the thrombectomy stent 1 and the stent tip 3, and the detachment of the stent tip 3 from the thrombectomy stent 1 is fundamentally avoided.

[0083] In one specific embodiment, the stent tip 3 includes a flexible tip with a solid structure, which can make the stent tip 3 bend along with the curvature of the blood vessel to enhance the passing performance.

[0084] From the perspective of the connection and cooperation between the stent tip 3 and the thrombectomy stent 1, the flexible tip is provided with a mounting part, and the mounting part includes a connecting counterbore 34 opened on the proximal surface of the flexible tip. The thrombectomy stent 1 includes a distal connecting section 11. Since the thrombectomy stent 1 is made of nitinol material and has a certain elasticity itself, the distal connecting section 11 can be elastically expanded outward and radially pressed in the connecting counterbore 34 to realize the tight connection and cooperation between the two.

[0085] The guide wire channel 33 includes a through hole opened on the flexible tip, which can effectively allow the guide wire 8 to pass through, and at the same time, enough radial space can be provided through the through hole to avoid the frictional interference of the guide wire 8 in the guide wire channel 33 and prevent the occurrence of frictional resistance between the guide wire 8 and the stent tip 3.

[0086] Based on the blood vessel passing performance and thrombus passing performance of the stent tip 3, at least a part of the solid region is left between the through hole and the connecting counterbore 34, which can form a certain solid structure to 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] From the perspective of ensuring that the guide wire 8 effectively passes through the guide wire channel 33 and, to the greatest extent possible, avoiding friction between the guide wire 8 and the stent tip 3, it is necessary to consider the movement space of the guide wire channel 33 relative to the guide wire 8. Specifically, the tip inlet 33a includes a circular hole provided in the stent tip 3, and the lateral outlet 33b includes an elliptical hole provided on the side wall of the stent tip 3. The elliptical hole includes at least a certain length. Through this setting method, a sufficient amount of movement space can be provided for the guide wire 8 in the guide wire channel 33, thereby avoiding the risk of frictional interference between the guide wire 8 and the stent tip 3.

[0088] When threading the guide wire 8 in this application, it is necessary to fully consider the straight threading state of the guide wire 8. From this perspective, the straight passage on the eccentrically bent tip 32 can better achieve this.

[0089] In the state of the bent passage 311 on the conical tip 31, in this application, the necessary structure of the guide wire channel 33 is set to avoid the influence of the bent passage 311 on the threading of the guide wire 8.

[0090] Specifically, when the stent tip 3 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 stent tip 3 and the thrombectomy stent 1 are coaxially arranged, the extending direction of the straight passage 312 coincides with the axis of the thrombectomy stent 1 and the stent tip 3, which can promote the guide wire 8 to thread at an angle parallel to the axis of both, avoiding frictional contact interference of the guide wire 8 on the straight passage 312.

[0091] Most importantly, the inclined passage 313 leads directly to the lateral outlet 33b with the same channel diameter as the straight passage 312, or more preferably, the inclined passage 313 leads directly 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 movement space for the guide wire 8 in the inclined passage 313, thereby reducing the risk of frictional contact interference between the guide wire 8 and the stent tip 3 at the bent passing part to the minimum.

[0092] Furthermore, the axis of the inclined passage 313 extends radially and obliquely from far to near relative to the stent tip 3, so that the 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 conveniently push and retract the thrombectomy stent 1, a pushing guide wire 4 is connected to the proximal end of the thrombectomy stent 1. The pushing guide wire 4 is woven by a plurality of stainless steel wires 41. Along the length direction of the pushing guide wire 4, a fixing block 42, a screwing section 43, a spiral section 44 and a connecting block 45 are arranged in sequence from near to far. The fixing block 42 mainly fixes the plurality of stainless steel wires 41 and is convenient for hand-held operation.

[0094] The screwing section 43 can maintain the screwing connection of the plurality of stainless steel wires 41, which is beneficial to integrating different stainless steel wires 41. The spiral section 44 includes a hollow cavity inside, which can enhance the overall flexibility of the pushing guide wire 4 and is more conducive to bending and adapting for variable-direction pushing.

[0095] The thrombectomy stent 1 includes a proximal connecting section 12. The proximal connecting section 12 and the connecting block 45 are fixedly connected through an adapter 46, and the front and back actions of the thrombectomy stent 1 can be controlled by pushing and pulling the pushing guide wire 4 back and forth.

[0096] It should be noted that the thrombectomy stent 1 and the pushing guide wire 4 are fixedly connected to ensure the stable and reliable connection between the thrombectomy stent 1 and the pushing guide wire 4.

[0097] Based on the above description, the adapter 46 includes a screwed taper head 46a. The screwed taper head 46a includes a tapered cylinder section on the proximal side and a straight cylinder section on the distal side. A connecting column 45a is fixedly arranged at the distal part of the connecting block 45. The connecting column 45a is threadedly connected to the tapered cylinder section of the screwed taper head 46a to realize the connection and fixation between the pushing guide wire 8 and the adapter 46.

[0098] From the connection angle between the thrombectomy stent 1 and the adapter 46, a connecting sleeve 46b is connected to the distal end of the screwed taper head 46a. The proximal connecting section 12 of the thrombectomy stent 1 passes through the connecting sleeve 46b and extends into and is fixed in the straight cylinder section of the screwed taper head 46a. Through this setting method, the proximal connecting section 12 can be fixedly installed on the connecting sleeve 46b and the screwed taper head 46a, thereby ensuring the stable and reliable connection.

[0099] Through this setting method, the reliable connection between the thrombectomy stent 1 and the pushing guide wire 8 can be realized through the adapter 46, and the detachment of the thrombectomy stent 1 can be fundamentally avoided.

[0100] Based on the threading of the thrombectomy stent 1 in the delivery catheter 2 and the ability to make the thrombectomy stent 1 telescopically move relative to the delivery catheter 2, the delivery catheter 2 in the present invention includes a single-lumen catheter and does not provide an additional guide wire lumen.

[0101] The wall of the single-lumen catheter comprises multiple layers of materials, including a PEBAX material on the outer layer, a stainless steel braided wire in the middle layer, and a PTFE material on the inner layer, which takes into account ensuring the passage of the delivery catheter 2 in the blood vessel through the outer layer, ensuring the smooth telescopic sliding of the thrombectomy stent 1 relative to the inner wall of the outer tube through the inner layer, and ensuring the pushing performance of the outer tube as a whole in the blood vessel through the middle layer. At the same time, the strength and flexibility of the overall structure are also comprehensively considered.

[0102] Since there is no separate guide wire lumen, the outer diameter of the delivery catheter 2 is not greater than 7F. A radio-opaque marker ring 21 is connected to the distal end of the delivery catheter 2, which can examine the positional relationship of the thrombectomy stent 1 relative to the distal end of the delivery catheter 2, so as to ensure the accurate release of the thrombectomy stent 1. A handle 22 with a luer connector 23 is connected to the proximal end of the delivery catheter 2, which facilitates the pulling operation.

[0103] From the perspective of facilitating the accurate cutting of the thrombus in the pulmonary artery thromboembolism after the in-situ release of the thrombectomy stent 1, since the thrombectomy stent 1 is a nickel-titanium alloy with memory elasticity, the thrombectomy stent 1 in the present invention includes multiple gourd-shaped sections in the released state. After the stent tip 3 passes through the mass thrombus, the thrombus can be divided into the annular waist grooves between multiple gourd sections after the release of the thrombectomy stent 1. Then, combined with the overall withdrawal of the pulmonary artery thrombectomy device, the thrombus is brought into the aspiration catheter 5 of the clearance system and removed from the blood vessel under the action of aspiration negative pressure.

[0104] It should be emphasized that in addition to having a certain degree of penetrability, the thrombectomy stent 1 can also endow a certain fixation function for the thrombus through its in-situ release, effectively avoiding the escape of the thrombus.

[0105] See Figure 8 and in combination with Figures 9 - 13 The present invention also provides a pulmonary artery thrombus clearance system, which includes an aspiration catheter 5, a dilator 6, a Y-shaped connector 9, and the above-mentioned pulmonary artery thrombectomy device. The distal end of the delivery catheter 2 is inserted into the aspiration catheter 5 and extends out from the distal end of the aspiration catheter 5. Further, the delivery catheter 2 is movably inserted into the aspiration catheter 5, which can drive the thrombectomy stent 1 to reach the distal part of the thrombus by the delivery catheter 2, and can make the thrombectomy stent 1 and the delivery catheter 2 have a relatively wide and flexible telescopic space.

[0106] The proximal end of the delivery catheter 2 is exposed outside the proximal end of the aspiration catheter 5, which can facilitate the pushing and pulling operation of the delivery catheter 2 and accurately control different working conditions.

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

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

[0109] During the use of the pulmonary artery thrombus removal system, the following steps are included:

[0110] After the aspiration catheter 5 and the dilator 6 are assembled, they are delivered to the thrombus position along the pre - placed guide wire 8. Under the guiding action of the guide wire 8, the dilator 6 can accurately reach the thrombus position. Then the dilator 6 is removed to obtain a good dilation path. When the dilator 6 establishes the path, the distal end of the dilator 6 does not pass through the thrombus. After staying on the proximal side of the thrombus, it indicates that the path - opening is completed. Then the dilator 6 is retracted.

[0111] Make the tail end of the guide wire 8 pass through the guide wire channel 33 of the stent tip 3, and along the guide wire 8 in the aspiration catheter 5, deliver the stent catheter assembly of the pulmonary artery thrombectomy device to the thrombus position, and make the stent tip 3 of the thrombectomy stent 1 pass through the thrombus, completing the penetration of the thrombus and fixing the thrombus from another angle.

[0112] Retract the delivery catheter 2, release the thrombectomy stent 1 in situ in the thrombus, so that the thrombectomy stent 1 cuts the thrombus in situ. Then, relative to the exposed release state relationship of the delivery catheter 2 with respect to the thrombectomy stent 1, synchronously retract the thrombectomy stent 1 and the delivery stent, so that the thrombectomy stent 1 undergoes elastic compression at the distal end opening of the aspiration catheter 5. Since the diameter of the aspiration catheter 5 is larger than that of the delivery catheter 2, the elastic compression amount is extremely smaller than the elastic compression amount when lying in the compression volume in the delivery catheter 2. Therefore, it can maintain the cutting and interception of the thrombus in a state of smaller compression deformation, and at the same time bring the cut - intercepted thrombus into the aspiration catheter 5. Combine with the aspirator 7 to perform negative pressure aspiration on the aspiration catheter 5, so that the small - sized cut thrombus is collected into the aspirator 7 through the aspiration catheter 5, completing the removal of the pulmonary artery thrombus.

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

[0114] It should be noted that, without conflict, the features in the embodiments of this application can be combined with each other.

[0115] The above are only the preferred embodiments of this application, and are not used to limit this application. For those skilled in the art, this application can have various changes and modifications. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of this application shall be included in the protection scope of this application.

Claims

1. A pulmonary artery thrombectomy device, characterized in that Comprising: A thrombectomy stent made of nitinol alloy and a delivery catheter, the thrombectomy stent being connected with a stent tip; The stent tip is limited and exposed at the distal nozzle of the delivery catheter, and the thrombectomy stent can axially extend forward and backward relative to the distal nozzle along the delivery catheter, so as to enable the thrombectomy stent to self-expand and release outside the distal nozzle and be elastically compressed inside the distal nozzle; A guide wire channel is provided on the stent tip, and the guide wire channel includes a tip inlet and a lateral outlet. The tip inlet is opened on the tip surface of the stent tip, and the lateral outlet is opened on the side wall of the stent tip, so as to enable the guide wire to guide and extend outside the delivery catheter; The stent tip includes a conical tip, the conical tip is coaxially arranged with the thrombectomy stent, and the guide wire channel includes a bent passage arranged on the conical tip; Alternatively, the stent tip includes an eccentric bent tip, the guide wire channel includes a straight passage arranged at the eccentric bent part, and the extending direction of the straight passage is parallel to the axis of the thrombectomy stent; The stent tip is detachably connected to the distal end of the thrombectomy stent, and the outer diameter of the proximal contour of the stent tip is not less than the outer diameter of the contour of the distal nozzle; The stent tip includes a flexible tip with a solid structure. The flexible tip is provided with a mounting part. The mounting part includes a connecting counterbore opened on the proximal surface of the flexible tip. The thrombectomy stent includes a distal connecting section. The distal connecting section elastically expands outward and radially presses in the connecting counterbore. The guide wire channel includes a through hole opened on the flexible tip, and there is at least a part of a solid area between the through hole and the connecting counterbore; The tip inlet includes a circular hole arranged on the stent tip, and the lateral outlet includes an elliptical hole arranged on the side wall of the stent tip. The elliptical hole includes at least one length; The bent passage on the conical tip includes a straight passage and an inclined passage. The extending direction of the straight passage coincides with the axis of the thrombectomy stent and the stent tip. The inclined passage leads directly to the lateral outlet with the same hole diameter as the straight passage or with a hole diameter larger than that of the straight passage, and the inclined passage extends obliquely from far to near relative to the axis of the stent tip. The included obtuse angle between the axis of the inclined passage and the axis of the straight passage is not less than 120°; 2. The pulmonary artery thrombectomy device according to claim 1, wherein A push guide wire is connected to the proximal end of the thrombectomy stent. The push guide wire is woven by multiple strands of stainless steel wires. A fixing block, a screwing section, a spiral section and a connecting block are sequentially arranged from near to far along the length direction of the push guide wire. The spiral section includes a hollow cavity inside. The thrombectomy stent includes a proximal connecting section, and the proximal connecting section and the connecting block are fixedly connected through a adapter; 3. The pulmonary artery thrombectomy device according to claim 2, wherein The adapter includes a screwed taper head. A connecting column is arranged at the distal end of the connecting block, and the connecting column is threadedly connected with the tapered cylinder section of the screwed taper head; The distal end of the screwed taper head is connected with an adapter sleeve, and the proximal connecting section passes through the adapter sleeve and extends into and is fixed in the straight cylinder section of the screwed taper head.

4. The pulmonary artery thrombectomy device according to claim 1, wherein The delivery catheter includes a single-lumen catheter. The wall of the single-lumen catheter comprises multiple layers of materials, including a PEBAX material in the outer layer, a stainless steel braided wire in the middle layer, and a PTFE material in the inner layer; The outer diameter of the delivery catheter is not greater than 7F. A radiopaque marker 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.

5. The pulmonary artery thrombectomy device according to claim 1, characterized in that, In the released state, the thrombectomy stent comprises multiple sections in a gourd shape and can cut the thrombus in the pulmonary artery through the stent mesh after release.

6. A pulmonary artery thrombus removal system, characterized in that, It includes a suction catheter, a dilator, a Y-shaped connector, and the pulmonary artery thrombectomy device according to any one of claims 1-5. The distal end of the delivery catheter is inserted into the suction catheter and extends out from the distal end of the suction catheter, and the proximal end of the delivery catheter is exposed outside the proximal end of the suction catheter; The Y-shaped connector is connected to the proximal end of the delivery catheter, and the thrombectomy stent enters the delivery catheter through the Y-shaped connector.

7. The pulmonary artery thrombus removal system according to claim 6, wherein, A suction tube is connected to the proximal end of the suction catheter, and a suction device is connected to the suction tube; During the use of the pulmonary artery thrombus removal system, the suction catheter and the dilator are assembled and then transported to the thrombus position along a pre-set guide wire. After reaching the thrombus position, the dilator is removed; The pulmonary artery thrombectomy device is transported to the thrombus position along the inner guide wire of the suction catheter, and the stent tip of the thrombectomy stent is passed through the thrombus; The delivery catheter is withdrawn, the thrombectomy stent is released in the thrombus, and then, relative to the exposed release state relationship of the thrombectomy stent to the delivery catheter, the thrombectomy stent and the delivery stent are synchronously withdrawn to bring the thrombus into the suction catheter, and the suction catheter is subjected to negative pressure suction by the suction device to complete the removal of the pulmonary artery thrombus.

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