Pulmonary artery thrombectomy apparatus and thrombus removal system
By setting a guidewire channel at the stent tip and eliminating the guidewire lumen, the outer diameter of the delivery catheter is reduced, solving the problem of pulmonary artery thrombectomy stent delivery, achieving efficient cutting and removal of pulmonary artery thrombi, and improving treatment outcomes.
Patent Information
- Authority / Receiving Office
- WO · WO
- Patent Type
- Applications
- Current Assignee / Owner
- GUANQIAO MEDICAL CO LTD
- Filing Date
- 2025-12-31
- Publication Date
- 2026-05-15
AI Technical Summary
The delivery catheters of existing pulmonary artery thrombectomy stents have excessively large outer diameters, which increases the difficulty of delivery and makes conventional treatment methods ineffective in removing pulmonary artery thrombi.
A pulmonary artery thrombectomy device is designed. By setting a guidewire channel at the stent tip, eliminating the guidewire lumen, reducing the outer diameter of the delivery catheter, and using various shapes and structures at the stent tip to facilitate the passage of thrombi, the device combines an aspiration catheter and a dilator to cut and remove thrombi.
It achieves efficient cutting and removal of pulmonary artery thrombi, reduces transport resistance, prevents thrombus escape, and improves treatment outcomes.
Abstract
Description
A pulmonary artery thrombectomy device and thrombus removal system
[0001] Cross-references to related applications
[0002] This disclosure claims priority to Chinese Patent Application No. 2024116006196, filed on November 11, 2024, entitled "A Pulmonary Artery Thrombectomy Device and Thrombus Removal System", the entire contents of which are incorporated herein by reference. Technical Field
[0003] This disclosure relates to the field of medical device technology, and more specifically, to a pulmonary artery thrombectomy device and a thrombus removal system. Background Technology
[0004] Pulmonary embolism is a pathological and clinical condition caused by an impacted substance entering the pulmonary artery and its branches, blocking the blood supply to the tissues. The most common embolus is a thrombus, while other less common causes include neoplasms, fat droplets, air bubbles, intravenously administered drug particles, and even the tip of a catheter causing pulmonary vascular obstruction.
[0005] Some pulmonary embolisms can dissolve spontaneously without treatment. However, studies have found that the mortality rate for untreated pulmonary embolisms exceeds 20%. Conventional treatments for thromboembolism include anticoagulation and thrombolysis, but these methods are not very effective and have many limitations depending on the patient's condition.
[0006] Currently, there are very few thrombectomy devices used on the pulmonary artery. The current instrumental treatment for pulmonary embolism is balloon dilation, which mechanically dilates the narrowed or occluded pulmonary artery to improve the flow of blood through it.
[0007] In publicly available pulmonary artery thrombectomy stents, delivery devices with guidewire lumens are generally used, resulting in a large diameter delivery device. The delivery tube diameter of commercially available products is 12F, which is punctured through the femoral vein, passes through the lower limb vein, right atrium and right ventricle to reach the pulmonary artery. The large diameter directly affects delivery and increases the difficulty for the stent to reach the pulmonary embolism site. Summary of the Invention
[0008] The purpose of this disclosure is to provide a pulmonary artery thrombectomy device and thrombus removal system that can solve the problem of excessively large outer diameter of the pulmonary artery thrombectomy stent delivery catheter. By not setting a guidewire lumen on the thrombectomy stent and delivery catheter, the outer diameter of the delivery catheter is reduced when the thrombectomy stent is pressed inside the delivery catheter. This allows the thrombectomy stent and delivery catheter to be delivered to more distant parts of the pulmonary artery or pulmonary artery branches. Furthermore, it facilitates the release of the thrombectomy stent after it has passed through the thrombus, thus preventing thrombus escape.
[0009] To achieve the above objectives, in a first aspect, this disclosure provides a pulmonary artery thrombectomy device, comprising: a thrombectomy stent made of nickel-titanium alloy, and a delivery catheter, wherein the thrombectomy stent is connected to a stent tip;
[0010] The tip of the stent is limited to being exposed at the distal end of the delivery conduit. The thrombectomy stent can extend and retract relative to the distal end of the delivery conduit along the axial direction of the delivery conduit, so that the thrombectomy stent can be self-expanded and released outside the distal end of the delivery conduit, and elastically compressed inside the distal end of the delivery conduit.
[0011] The stent tip is provided with a guide wire channel, which includes a tip inlet and a lateral outlet. The tip inlet is located on the tip surface of the stent tip, and the lateral outlet is located on the side wall of the stent tip, so as to allow the guide wire to be guided and extended outside the delivery catheter.
[0012] The stent tip includes a tapered tip, which is coaxially arranged with the thrombectomy stent, and the guide wire channel includes a bent passage provided on the tapered tip;
[0013] Alternatively, the stent tip may include an eccentrically bent tip, and the guide wire channel may include a straight passage disposed at the eccentrically bent portion, wherein the extending direction of the straight passage is parallel to the axial direction of the thrombectomy stent.
[0014] The tip of the support is detachably connected to the distal end of the thrombectomy support, and the outer diameter of the proximal profile of the support tip is not less than the outer diameter of the distal end of the tube.
[0015] In an optional embodiment, the stent tip includes a solid flexible tip, the flexible tip is provided with a mounting portion, the mounting portion includes a connecting countersunk hole formed on the proximal end face of the flexible tip, and the thrombectomy stent includes a distal connecting segment, the distal connecting segment elastically expanding outward and radially pressed into the connecting countersunk hole.
[0016] In an optional embodiment, the guidewire channel includes a through-hole formed on the flexible tip.
[0017] In an optional embodiment, at least a solid area is left between the through hole and the connecting countersunk hole.
[0018] In an optional embodiment, the tip inlet includes a circular hole disposed at the tip of the support, and the lateral outlet includes an elliptical hole disposed on the sidewall of the tip of the support, the elliptical hole including at least a length.
[0019] In an optional embodiment, the bend in the conical tip includes a straight path and an inclined path. The straight path extends in the direction of the thrombectomy bracket and the axis of the bracket tip. The inclined path extends to the lateral outlet with the same or larger diameter as the straight path.
[0020] In an optional embodiment, the inclined passage extends outward from far to near the axial direction of the support tip.
[0021] In an optional embodiment, the obtuse angle between the axis of the inclined path and the axis of the straight path is not less than 120°.
[0022] In an optional embodiment, the proximal end of the thrombectomy bracket is connected to a push guide wire, which is woven from multiple strands of stainless steel wire. Along the length of the push guide wire, from near to far, there are a fixing block, a screwing section, a spiral section, and a connecting block. The spiral section includes a hollow cavity located inside. The thrombectomy bracket includes a proximal connecting section, and the proximal connecting section and the connecting block are connected and fixed by an adapter.
[0023] In an optional embodiment, the adapter includes a threaded cone head, and a connecting post is provided at the distal end of the connecting block, the connecting post being threadedly connected to the tapered section of the threaded cone head;
[0024] The distal end of the threaded cone is connected to an adapter sleeve, and the proximal connecting section passes through the adapter sleeve and extends into the straight section fixed to the threaded cone.
[0025] In an optional embodiment, the delivery conduit includes a single-lumen conduit, the wall of which comprises multiple layers of material, including an outer layer of PEBAX material, a middle layer of stainless steel braided wire, and an inner layer of PTFE material.
[0026] In an optional embodiment, the outer diameter of the delivery conduit is no greater than 7F.
[0027] In an optional embodiment, a radiopaque marking ring is connected to the distal end of the delivery conduit.
[0028] In an alternative embodiment, the proximal end of the delivery conduit is connected to a handle with an attached Luer connector.
[0029] In an optional embodiment, the thrombectomy stent, in its released state, comprises multiple gourd-shaped segments, capable of cutting thrombi in the pulmonary artery through the stent mesh after release.
[0030] Secondly, this disclosure provides a pulmonary artery thrombectomy system, including an aspiration catheter, a dilator, a Y-type connector, and a pulmonary artery thrombectomy device as described in any of the foregoing embodiments, wherein 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.
[0031] The Y-type connector is connected to the proximal end of the delivery catheter, and the thrombectomy stent enters the delivery catheter through the Y-type connector.
[0032] In an optional embodiment, the proximal end of the suction conduit is connected to a suction tube, and a suction device is connected to the suction tube.
[0033] During use, the pulmonary artery thrombosis removal system is assembled with the aspiration catheter and dilator and then delivered to the thrombus location along the pre-placed guidewire. Once the thrombus location is reached, the dilator is removed.
[0034] The pulmonary thrombectomy device is delivered to the thrombus site along the guidewire inside the aspiration catheter, and the stent tip of the thrombectomy stent passes through the thrombus.
[0035] The delivery catheter is retracted, and the thrombectomy stent is released into the thrombus. Then, relative to the exposed release state of the thrombectomy stent and the delivery catheter, the thrombectomy stent and the delivery stent are retracted simultaneously to bring the thrombus into the aspiration catheter. The aspiration catheter is then subjected to negative pressure aspiration using an aspirator to complete the removal of the pulmonary thrombus.
[0036] The pulmonary artery thrombectomy device disclosed herein, by limiting the stent tip to be exposed at the distal end of the delivery catheter and by setting the guidewire channel on the stent tip between the tip and the sidewall of the stent tip, can form a straight-in, side-out guidewire on the stent tip, thereby constituting the lateral exit of the guidewire. This avoids the need to set additional catheter lumens on the thrombectomy stent and the delivery catheter, and can minimize the diameter of the delivery catheter to the greatest extent, allowing the thrombectomy stent, which is elastically compressed inside its distal end, to smoothly pass through the vascular path to the designated location.
[0037] Meanwhile, compared to the tree-like structure of pulmonary arteries with many branches, the smaller diameter delivery catheter can smoothly guide the thrombectomy stent through the vascular path to the designated location. On the one hand, it facilitates the passage of the delivery catheter and stent tip through the thrombus, and on the other hand, it can avoid thrombus displacement. The thrombectomy stent, after self-expanding and releasing upon reaching the designated location, can effectively cut the thrombus at the designated site, which is conducive to subsequent aspiration and removal.
[0038] The different shapes and structures of the stent tip can help reduce the delivery resistance of the stent when it is not deployed, or make it easier for the stent tip to pass through the thrombus. Combined with the different types of guidewire channels corresponding to the stent tip on different structures, the guidewire and guidewire channel can be better matched, and the stent tip can be pushed more smoothly under the guidance of the guidewire.
[0039] By detachably connecting the stent tip to the distal end of the thrombectomy stent, it can be flexibly replaced according to different application conditions, making it easy to adjust for different types of patients.
[0040] The outer diameter of the proximal profile of the stent tip is not less than the outer diameter of the distal end of the delivery catheter. This allows the distal end of the delivery catheter to form the necessary limiting relationship, ensuring that the stent tip is only limited to being exposed outside the delivery catheter and does not retract into the delivery catheter. This ensures effective cooperation between the stent tip and the guidewire outside the delivery catheter, while also enabling the stent tip, which is limited to being exposed at the distal end, to act as a good open circuit structure.
[0041] Other features and advantages of this disclosure will be described in detail in the following detailed description section. Attached Figure Description
[0042] To more clearly illustrate the technical solutions of the embodiments of this disclosure, the accompanying drawings used in the embodiments will be briefly described below. It should be understood that the following drawings only show some embodiments of this disclosure and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.
[0043] Figure 1 is a schematic diagram of the overall structure of the pulmonary artery thrombectomy device and the Y-type connector;
[0044] Figure 2 is a schematic diagram of the thrombectomy stent;
[0045] Figure 3 is a schematic diagram of the delivery conduit;
[0046] Figure 4 is a schematic diagram of the Y-type connector;
[0047] Figure 5 is a schematic diagram of the structure of the conical tip;
[0048] Figure 6 is a schematic diagram of the eccentrically bent tip;
[0049] Figure 7 is a schematic diagram of the structure for pushing the guidewire;
[0050] Figure 8 is a schematic diagram of the pulmonary artery thrombus removal system;
[0051] Figure 9 is a schematic diagram of the assembly structure of the suction catheter and the dilator;
[0052] Figure 10 is a schematic diagram of the open-circuit state structure of the expander;
[0053] Figure 11 is a schematic diagram of the state structure after the expander is removed;
[0054] Figure 12 is a schematic diagram of the structure with the stent tip passing through the thrombus;
[0055] Figure 13 is a schematic diagram of the aspiration state after the thrombectomy stent is released.
[0056] Icons: 1-Thrombectomy bracket; 11-Distal connection segment; 12-Proximal connection segment; 2-Delivery catheter; 21-Non-transparent marking ring; 22-Handle; 23-Luer connector; 3-Staff tip; 31-Conical tip; 311-Bent path; 312-Straight path; 313-Inclined path; 32-Eccentric bent tip; 33-Guidewire channel; 33a-Tip inlet; 33b-Lateral outlet; 34-Connecting countersunk hole; 4-Push guidewire; 41-Stainless steel wire; 42-Fixing block; 43-Twisting section; 44-Helical section; 45-Connecting block; 45a-Connecting post; 46-Adapter; 46a-Screwed cone; 46b-Adapter sleeve; 5-Aspiration catheter; 51-Aspiration tube; 6-Expander; 7-Aspirator; 8-Guidewire; 9-Y-connector. Detailed Implementation
[0057] To make the objectives, technical solutions, and advantages of the embodiments of this disclosure clearer, the technical solutions of the embodiments of this disclosure will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this disclosure. The components of the embodiments of this disclosure described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.
[0058] In the description of this disclosure, it should be noted that the terms "inner," "outer," etc., indicating the orientation or positional relationship are based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship commonly used when the product is in use. They are only for the convenience of describing this disclosure and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this disclosure. In addition, the terms "first," "second," etc., are only configured to distinguish the description and should not be construed as indicating or implying relative importance.
[0059] In the description of this disclosure, it should also be noted that, unless otherwise expressly specified and limited, the terms "setup" and "connection" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this disclosure based on the specific circumstances.
[0060] Referring to Figure 1, and in conjunction with Figures 2-7, the pulmonary artery thrombectomy device of this disclosure is mainly used for the treatment and removal of thrombi in pulmonary arteries. Specifically, by changing the connection method of the guidewire 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 many branches as much as possible. The thrombus is then cut by the in-situ release of the thrombectomy stent 1, and then the thrombus is removed by subsequent aspiration.
[0061] By changing the guiding and connection method of the guidewire 8 to the thrombectomy stent 1 and the delivery catheter 2, the permeability of the delivery catheter 2 in the pulmonary artery is maximized, and the thrombectomy stent 1 can be effectively and reliably delivered to the thrombus site.
[0062] Referring to Figure 1, the pulmonary artery thrombectomy device of this disclosure has a main structure including a thrombectomy stent 1 made of nickel-titanium alloy and a delivery catheter 2 configured to deliver the thrombectomy stent 1. During the delivery process, the tip of the thrombectomy stent 1 is exposed in the delivery catheter 2, which is configured to enhance the permeability of the stent-catheter assembly formed by the thrombectomy stent 1 and the delivery catheter 2. The stent-catheter assembly specifically refers to the assembly in which the thrombectomy stent 1 is elastically compressed in the delivery catheter 2.
[0063] With the stent tip 3 connected to the thrombectomy stent 1, the stent tip 3 in this disclosure is always in a limited, exposed state at 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. Especially during the delivery of the thrombectomy stent 1 in its compressed state to the distal end of the blood vessel, the stent tip 3 can establish a good pushing path, thereby reducing the pushing resistance.
[0064] The thrombectomy stent 1 can extend and retract along the axial direction of the delivery catheter 2 relative to the distal end of the delivery catheter 2, so that the thrombectomy stent 1 can be self-expanded and released on the outside of the distal end of the delivery catheter 2, and elastically compressed on the inside of the distal end of the delivery catheter 2.
[0065] Specifically, during the delivery of the stent catheter assembly, the thrombectomy stent 1 is elastically compressed on the inner side of the distal end of the catheter. When the stent catheter assembly is delivered to the thrombus site, especially when the stent tip 3 has just passed through and reached the distal end of the thrombus, the delivery catheter 2 is retracted to move relative to the thrombectomy stent 1, causing the thrombectomy stent 1 to extend out of the distal end of the delivery catheter 2. The thrombectomy stent 1 self-expands and releases at the thrombus site, and simultaneously cuts the thrombus in situ, thereby achieving the thrombus cutting treatment.
[0066] During the relevant delivery process, the thrombectomy stent 1 and the delivery catheter 2 are guided by the guidewire 8 passing through their internal guidewire lumen. Specifically, when the thrombectomy device is inserted into the blood vessel from outside the body, the tail end of the guidewire 8 exposed outside the body is inserted into the guidewire lumen and extends from the proximal end of the thrombectomy device. Under the guidance of the guidewire 8, the thrombectomy device is inserted into the blood vessel and reaches the predetermined target site.
[0067] This disclosure breaks through the relevant understanding by not inserting the guidewire 8 into the thrombectomy stent 1 and / or delivery catheter 2. Instead, it uses a lateral guidewire channel 33 on the stent tip 3, combined with the stent tip 3 being exposed outside the delivery catheter 2 at all times, as described above. This allows the guidewire 8 to be guided laterally and thus inserted outside the delivery catheter 2. This avoids the need to set a dedicated guidewire lumen inside the delivery catheter 2 or on the thrombectomy stent 1, thereby significantly reducing the outer diameter of the stent-catheter assembly, especially the delivery catheter 2, making it more suitable for delivery in smaller, more branched pulmonary arteries.
[0068] Meanwhile, from another perspective, although the relevant thrombectomy stent 1 also has some guidewire-less lumen settings, it is more often used for thrombectomy in cranial arteries. Compared to the cranial arteries 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 site of the cranial artery. However, this application scenario cannot be compared with the structure of the pulmonary artery with more branches in this disclosure. Without the guidance of the guidewire 8, the thrombectomy stent 1 has difficulty reaching the designated location of the pulmonary artery. In the relevant understanding, the application of the cranial artery guidewire-less thrombectomy stent 1 and the direct access to the designated lesion site of the cranial artery without the guidance of the guidewire 8 cannot be associated with the structure of the guidewire 8 and the guidewire channel 33 on the side of the stent tip 3 in this disclosure. Here, we will explain from the perspective of actual application.
[0069] As shown in Figure 6, the lateral guide wire channel 33 on the tip 3 of the support in this disclosure specifically includes a tip inlet 33a and a lateral outlet 33b. The tip inlet 33a referred to here is the reverse insertion inlet of the tail end of the guide wire 8. The tip inlet 33a is opened on the tip surface of the tip 3 of the support.
[0070] The lateral outlet 33b is the reverse insertion 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. The ultimate purpose of this arrangement is to combine the exposure of the stent tip 3 at the distal end of the delivery conduit 2 so that the guide wire 8 can be guided and extended outside the delivery conduit 2.
[0071] It is worth adding that most of the pulmonary artery thrombectomy stents 1 are delivery catheters 2 with guidewire lumens, which results in a large diameter of delivery catheter 2. The outer diameter of the delivery catheter 2 of the products already on the market is 12F. It is punctured through the femoral vein, passes through the lower limb vein, right atrium and right ventricle to reach the pulmonary artery. The large diameter directly affects the delivery and increases the difficulty for the thrombectomy stent 1 to reach the pulmonary embolism site, i.e., the pulmonary thrombus site.
[0072] By guiding the guidewire 8 to extend outside the delivery catheter 2, the outer diameter of the delivery catheter 2 is significantly reduced, keeping it within 7F. This allows the thrombectomy stent 1 to smoothly pass through the vascular pathway to the designated location. The reduced outer diameter of the delivery catheter 2 facilitates the overall stent-catheter assembly's passage through the thrombus, especially with the exposed open path of the stent tip 3, making it easier for the delivery catheter 2 to pass through the thrombus while preventing thrombus displacement. This allows the relatively stable thrombus to be effectively cut and processed after the thrombectomy stent 1 is released.
[0073] The stent tip 3 in this disclosure specifically serves to establish an open circuit and facilitate the passage of the thrombus. It can be selected and configured according to specific needs in different application scenarios.
[0074] Specifically, as shown in Figure 5, the stent tip 3 includes a commonly used tapered tip 31, which is coaxially arranged with the thrombectomy stent 1. The guidewire channel 33 includes a bent passage 311 arranged on the tapered tip 31. This arrangement allows the stent tip 3 to pass through the thrombus more easily, making it suitable for the treatment of larger pulmonary thrombi.
[0075] Meanwhile, the stent tip 3 also includes an eccentrically bent tip 32, and the guidewire channel 33 includes a straight passage located at the eccentrically bent part, and the extension direction of the straight passage is parallel to the axis of the thrombectomy stent 1. Obviously, the straight passage of the eccentrically bent tip 32 can reduce the resistance when delivering along the guidewire 8, minimize the frictional interference between the guidewire 8 and the stent tip 3, and is suitable for branch pulmonary arteries, making it easier to pass through tortuous blood vessels.
[0076] Regardless of the method used, the guidewire 8 can be extended on the outside of the delivery catheter 2, thereby achieving the technical objective of reducing the outer diameter of the delivery catheter 2.
[0077] 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 profile of the stent tip 3 is not less than the outer diameter of the distal end of the tube, so as to limit the stent tip 3 to be exposed at the distal end of the delivery catheter 2.
[0078] The stent tip 3 is detachably connected, which is determined by the specific application scenario of the delivery catheter 2 and the thrombectomy stent 1 in this disclosure. 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 situ released, while the delivery catheter 2 moves back relative to the thrombectomy stent 1 to avoid the relative release space.
[0079] After the thrombectomy stent 1 is deployed and completes in-situ dissection of the thrombus, the thrombectomy stent 1 and delivery catheter 2 are simultaneously withdrawn, allowing them to enter the aspiration catheter 5 of the thrombus removal system together. Since the delivery catheter 2 is not pushed forward relative to the thrombectomy stent 1, only the tightness of the fit between the stent tip 3 and the thrombectomy stent 1 needs to be considered. Simultaneously, because the proximal stent body of the stent tip 3 has already released and dissected the thrombus, the thrombus's resistance to the withdrawal of the stent tip 3 is minimized. Therefore, the tight fit between the distal portion of the thrombectomy stent 1 and the stent tip 3 ensures the overall integration of the two, fundamentally preventing the stent tip 3 from detaching from the thrombectomy stent 1.
[0080] In one specific embodiment, the stent tip 3 includes a flexible tip with a solid structure, which enables the stent tip 3 to bend in accordance with the curvature of the blood vessel, thereby enhancing the passage performance.
[0081] As shown in Figures 5 and 6, regarding the connection and fit between the flexible tip 3 and the thrombectomy bracket 1, the flexible tip is provided with a mounting portion, which includes a countersunk hole 34 formed on the proximal end face of the flexible tip. As shown in Figure 2, the thrombectomy bracket 1 includes a distal connecting section 11. Since the thrombectomy bracket 1 is made of nickel-titanium alloy, it has a certain degree of elasticity, which allows the distal connecting section 11 to expand elastically outward and be radially pressed into the countersunk hole 34, achieving a tight connection and fit between the two.
[0082] The guide wire channel 33 includes a through-hole formed on the flexible tip, which allows the guide wire 8 to be effectively passed through. At the same time, the through-hole provides sufficient radial space to avoid frictional interference of the guide wire 8 in the guide wire channel 33 and prevent frictional resistance between the guide wire 8 and the support tip 3.
[0083] Based on the vascular passability and thrombus penetration of the stent tip 3, at least a solid area is left between the through-hole and the connecting countersunk hole 34 to form a certain solid structure, so as to avoid the structural strength of the stent tip 3 being affected by the opening of the through-hole and to prevent the stent tip 3 from bending when passing through the blood vessel and thrombus.
[0084] To ensure the guidewire 8 can effectively pass through the guidewire channel 33 at a certain angle, and to minimize friction between the guidewire 8 and the stent tip 3, the relative movement space of the guidewire channel 33 and the guidewire 8 needs to be considered. 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 in the sidewall of the stent tip 3, the elliptical hole including at least a certain length. This arrangement provides sufficient movement space for the guidewire 8 in the guidewire channel 33, thereby avoiding the risk of frictional interference between the guidewire 8 and the stent tip 3.
[0085] In this disclosure, the straight-line insertion state of the guidewire 8 must be fully considered. At this angle, the straight path on the eccentric bend tip 32 can be better realized.
[0086] In the case of the bent passage 311 on the conical tip 31, this disclosure avoids the influence of the bent passage 311 on the guide wire 8 by setting the necessary guide wire channel 33 structure.
[0087] Specifically, as shown in Figure 5, when the tip 3 of the support is a tapered tip 31, the bent passage 311 on the tapered tip 31 includes a straight passage 312 and an inclined passage 313. Based on the coaxial arrangement of the tip 3 of the support and the thrombectomy support 1, the extension direction of the straight passage 312 coincides with the axis of the thrombectomy support 1 and the tip 3 of the support, which can cause the guide wire 8 to be inserted at an angle parallel to the axis of both, avoiding frictional contact interference of the guide wire 8 on the straight passage 312.
[0088] Optionally, the inclined passage 313 extends directly to the lateral outlet 33b with the same channel diameter as the straight passage 312, or the inclined passage 313 extends directly to the lateral outlet 33b with a larger channel diameter than the straight passage 312, so as to provide a larger amount of room for the guidewire 8 to move in the inclined passage 313, thereby minimizing the risk of frictional contact interference between the guidewire 8 and the support tip 3 at the bending passage.
[0089] Optionally, the inclined passage 313 extends radially outward from the far end to the near end 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 guidewire 8 in the bending passage 311 and reducing the risk of frictional contact interference between the guidewire 8, especially the bending part of the guidewire 8, and the stent tip 3.
[0090] In another specific embodiment, as shown in Figures 2 and 7, in order to facilitate the pushing and retraction control of the thrombectomy bracket 1, a push guide wire 4 is connected to the proximal end of the thrombectomy bracket 1. The push guide wire 4 is woven from multiple strands of stainless steel wire 41. Along the length direction of the push guide wire 4, from near to far, a fixing block 42, a twisting section 43, a spiral section 44, and a connecting block 45 are arranged in sequence. The fixing block 42 mainly fixes the multiple strands of stainless steel wire 41 and facilitates hand operation.
[0091] The twisting section 43 can maintain the twisted connection of multiple stainless steel wires 41, which is conducive to the integration of different stainless steel wires 41. The spiral section 44 includes an internal hollow cavity, which can enhance the overall flexibility of the guide wire 4 and make it easier to perform bending and directional pushing.
[0092] The thrombectomy stent 1 includes a proximal connecting section 12, which is connected and fixed to the connecting block 45 via an adapter 46. The forward and backward movement of the thrombectomy stent 1 can be controlled by pushing and pulling the guide wire 4.
[0093] It should be noted that the thrombectomy bracket 1 and the push guide wire 4 are fixedly connected to ensure the stability and reliability of the connection between the thrombectomy bracket 1 and the push guide wire 4.
[0094] Based on the above description, the adapter 46 includes a threaded cone 46a, which includes a conical section on the proximal side and a straight section on the distal side. A connecting post 45a is fixedly provided at the distal end of the connecting block 45. The connecting post 45a is threadedly connected to the conical section of the threaded cone 46a, thereby realizing the connection and fixation between the push guide wire 8 and the adapter 46.
[0095] From the connection angle between the bolt pick bracket 1 and the adapter 46, the distal end of the screw-connected cone 46a is connected to the adapter sleeve 46b, and the proximal connecting section 12 of the bolt pick bracket 1 passes through the adapter sleeve 46b and extends into the straight section fixed to the screw-connected cone 46a. With this arrangement, the proximal connecting section 12 can be fixedly installed on the adapter sleeve 46b and the screw-connected cone 46a, thereby ensuring the stability and reliability of the connection.
[0096] With this configuration, a reliable connection between the thrombectomy bracket 1 and the push guide wire 8 can be achieved through the adapter 46, fundamentally preventing the thrombectomy bracket 1 from detaching.
[0097] Based on the insertion of the thrombectomy stent 1 into the delivery catheter 2, and the ability of the thrombectomy stent 1 to extend and retract relative to the delivery catheter 2, the delivery catheter 2 in this disclosure includes a single-lumen catheter and does not have an additional guidewire lumen.
[0098] The single-lumen catheter has a wall made of multiple layers, including an outer layer of PEBAX material, a middle layer of stainless steel braided wire, and an inner layer of PTFE material. This design balances the need for the outer layer to ensure the passage of the delivery catheter 2 through the blood vessel, the inner layer to ensure the smooth sliding of the thrombectomy stent 1 relative to the inner wall of the outer tube, and the middle layer to ensure the overall pushing performance of the outer tube in the blood vessel. It also takes into account the strength and flexibility of the overall structure.
[0099] Since there is no separate guidewire lumen, the outer diameter of the delivery catheter 2 is no greater than 7F. Furthermore, as shown in Figure 3, a radiopaque marking ring 21 is connected to the distal end of the delivery catheter 2, allowing for examination of the positional relationship between the thrombectomy stent 1 and the distal end of the delivery catheter 2, thereby ensuring 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, facilitating easy pull-out operation.
[0100] From the perspective of facilitating the in-situ release of the thrombectomy stent 1, it is possible to precisely cut the thrombus in the pulmonary thrombosis. Since the thrombectomy stent 1 is a nickel-titanium alloy with memory elasticity, the thrombectomy stent 1 in the released state includes multiple gourd-shaped segments. After the stent tip 3 passes through the clump of thrombus, the thrombus can be divided into the annular groove between the multiple gourd segments after the thrombectomy stent 1 is released. Then, combined with the overall retraction of the pulmonary 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 suction negative pressure.
[0101] It is important to note that, in addition to having a certain degree of permeability, the thrombectomy stent 1 can also provide a certain degree of fixation for the thrombus through its in-situ release, effectively preventing the thrombus from escaping.
[0102] Referring to Figure 8, and in conjunction with Figures 9-13, this disclosure also provides a pulmonary artery thrombectomy system, including an aspiration catheter 5, a dilator 6, a Y-type connector 9, and the aforementioned 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. Optionally, the delivery catheter 2 is movably inserted into the aspiration catheter 5, which enables the delivery catheter 2 to drive the thrombectomy stent 1 to the distal part of the thrombus, and enables the thrombectomy stent 1 and the delivery catheter 2 to have a relatively wide and flexible range of extension and retraction.
[0103] The proximal end of the delivery conduit 2 is exposed outside the proximal end of the suction conduit 5, allowing for flexible and convenient pushing and pulling operations of the delivery conduit 2, and precise control of different working conditions.
[0104] Y-type connector 9 is connected to the proximal end of delivery catheter 2, and thrombectomy stent 1 enters the lumen of delivery catheter 2 through Y-type connector 9.
[0105] The proximal end of the suction catheter 5 is connected to a suction tube 51, and a suction device 7 is connected to the suction tube 51. With the suction device 7, suction operation can be performed to establish a stable and reliable suction negative pressure for the suction catheter 5.
[0106] The pulmonary thrombus removal system includes the following steps during use:
[0107] After the aspiration catheter 5 and the dilator 6 are assembled, they are delivered to the thrombus location along the pre-placed guidewire 8. Under the guidance of the guidewire 8, the dilator 6 can accurately reach the thrombus location. Then the dilator 6 is removed to obtain a good dilation pathway. When the pathway is established, the distal end of the dilator 6 does not pass through the thrombus. Instead, it stays on the proximal side of the thrombus, indicating that the opening is complete. Then the dilator 6 is withdrawn.
[0108] The tail end of the guidewire 8 is passed through the guidewire channel 33 of the stent tip 3, and the stent catheter assembly of the pulmonary artery thrombectomy device is delivered to the thrombus location along the guidewire 8 inside the aspiration catheter 5. The stent tip 3 of the thrombectomy stent 1 passes through the thrombus, completing the passage of the thrombus and fixing the thrombus from another angle.
[0109] The delivery catheter 2 is retracted, and the thrombectomy stent 1 is released in situ within the thrombus, allowing the stent 1 to cut the thrombus in situ. Then, relative to the exposed release state of the stent 1 and the delivery catheter 2, the stent 1 and the delivery stent are retracted simultaneously, causing the stent 1 to undergo elastic compression at the distal end of the aspiration catheter 5. Since the diameter of the aspiration catheter 5 is larger than that of the delivery catheter 2, the amount of elastic compression is much smaller than that when the catheter is compressed and placed in the delivery catheter 2. Therefore, the stent 1 can maintain the cutting and interception of the thrombus with a smaller compression deformation state. At the same time, the cut and intercepted thrombus is brought into the aspiration catheter 5. Combined with the aspiration device 7, the aspiration catheter 5 is subjected to negative pressure aspiration, allowing the small-sized thrombus after cutting to be collected into the aspiration device 7 through the aspiration catheter 5, thus completing the removal of the pulmonary thrombus.
[0110] The pulmonary thrombus removal system disclosed herein can fundamentally guarantee the removal of thrombi in pulmonary arteries, providing technical support for the timely and reliable treatment of pulmonary embolism.
[0111] It should be noted that, where there is no conflict, the features in the embodiments of this disclosure can be combined with each other.
[0112] The above description is merely a preferred embodiment of this disclosure and is not intended to limit the scope of this disclosure. Various modifications and variations can be made to this disclosure by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this disclosure should be included within the scope of protection of this disclosure. Industrial applicability
[0113] In summary, this disclosure provides a pulmonary artery thrombectomy device and thrombus removal system, which can solve the problem of excessively large outer diameter of the pulmonary artery thrombectomy stent delivery catheter. By eliminating the need for a guidewire lumen in the thrombectomy stent and delivery catheter, the outer diameter of the delivery catheter is reduced when the thrombectomy stent is compressed within the catheter. Therefore, this disclosure allows the thrombectomy stent and delivery catheter to be delivered to more distal locations in the pulmonary artery or its branches, and facilitates stent release after passing through the thrombus, preventing thrombus escape.
Claims
1. A pulmonary artery thrombectomy device, characterized in that, include: A thrombectomy stent made of nickel-titanium alloy and a delivery conduit, wherein the thrombectomy stent is connected to a stent tip; The tip of the stent is limited to being exposed at the distal end of the delivery conduit. The thrombectomy stent can extend and retract relative to the distal end of the delivery conduit along the axial direction of the delivery conduit, so that the thrombectomy stent can be self-expanded and released outside the distal end of the delivery conduit, and elastically compressed inside the distal end of the delivery conduit. The stent tip is provided with a guide wire channel, which includes a tip inlet and a lateral outlet. The tip inlet is located on the tip surface of the stent tip, and the lateral outlet is located on the side wall of the stent tip, so as to allow the guide wire to be guided and extended outside the delivery catheter. The stent tip includes a tapered tip, which is coaxially arranged with the thrombectomy stent, and the guide wire channel includes a bent passage provided on the tapered tip; Alternatively, the stent tip may include an eccentrically bent tip, and the guide wire channel may include a straight passage disposed at the eccentrically bent portion, wherein the extending direction of the straight passage is parallel to the axial direction of the thrombectomy stent. The tip of the support is detachably connected to the distal end of the thrombectomy support, and the outer diameter of the proximal profile of the support tip is not less than the outer diameter of the distal end of the tube.
2. The pulmonary artery thrombectomy device according to claim 1, characterized in that, The tip of the support includes a solid flexible tip, the flexible tip is provided with a mounting part, the mounting part includes a connecting countersunk hole opened on the proximal end face of the flexible tip, and the thrombectomy support includes a distal connecting section, the distal connecting section elastically expands outward and is radially pressed into the connecting countersunk hole.
3. The pulmonary artery thrombectomy device according to claim 2, characterized in that, The guidewire channel includes a through-hole formed on the flexible tip.
4. The pulmonary artery thrombectomy device according to claim 3, characterized in that, At least a solid area is left between the through hole and the connecting countersunk hole.
5. The pulmonary artery thrombectomy device according to any one of claims 1 to 4, characterized in that, The tip inlet includes a circular hole disposed at the tip of the support, and the lateral outlet includes an elliptical hole disposed on the sidewall of the tip of the support, the elliptical hole including at least a length.
6. The pulmonary artery thrombectomy device according to any one of claims 1 to 5, characterized in that, The bend in the conical tip includes a straight path and an inclined path. The straight path extends in the same direction as the thrombectomy bracket and the axis of the bracket tip. The inclined path extends to the lateral outlet with the same or larger diameter as the straight path.
7. The pulmonary artery thrombectomy device according to claim 6, characterized in that, The inclined passage extends outward from the far end to the near end relative to the axial direction of the support tip.
8. The pulmonary artery thrombectomy device according to claim 7, characterized in that, The obtuse angle between the axis of the inclined path and the axis of the straight path is not less than 120°.
9. The pulmonary artery thrombectomy device according to any one of claims 1 to 8, characterized in that, The proximal end of the thrombectomy bracket is connected to a push guide wire, which is made of multiple strands of stainless steel wire. Along the length of the push guide wire, from near to far, there are a fixing block, a screwing section, a spiral section, and a connecting block. The spiral section includes an internal hollow cavity. The thrombectomy bracket includes a proximal connecting section, which is connected and fixed to the connecting block by an adapter.
10. The pulmonary artery thrombectomy device according to claim 9, characterized in that, The adapter includes a threaded cone head, and the far end of the connecting block is provided with a connecting post, which is threadedly connected to the cone section of the threaded cone head. The distal end of the threaded cone is connected to an adapter sleeve, and the proximal connecting section passes through the adapter sleeve and extends into the straight section fixed to the threaded cone.
11. The pulmonary artery thrombectomy device according to any one of claims 1 to 10, characterized in that, The delivery conduit includes a single-lumen conduit, the wall of which comprises multiple layers of material, including an outer layer of PEBAX material, a middle layer of stainless steel braided wire, and an inner layer of PTFE material.
12. The pulmonary artery thrombectomy device according to any one of claims 1 to 11, characterized in that, The outer diameter of the delivery conduit is no greater than 7F.
13. The pulmonary artery thrombectomy device according to any one of claims 1 to 12, characterized in that, A radiopaque marking ring is connected to the distal end of the delivery conduit.
14. The pulmonary artery thrombectomy device according to any one of claims 1 to 13, characterized in that, The proximal end of the delivery conduit is connected to a handle with an attached Luer connector.
15. The pulmonary artery thrombectomy device according to any one of claims 1 to 14, characterized in that, The thrombectomy stent, in its deployed state, comprises multiple gourd-shaped segments and can cut thrombi in the pulmonary artery through the stent mesh after deployment.
16. A pulmonary artery thrombus removal system, characterized in that, The device includes an aspiration catheter, a dilator, a Y-connector, and a pulmonary thrombectomy device according to any one of claims 1 to 15, wherein 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. The Y-type connector is connected to the proximal end of the delivery catheter, and the thrombectomy stent enters the delivery catheter through the Y-type connector.
17. The pulmonary thrombus removal system according to claim 16, characterized in that, The proximal end of the suction conduit is connected to a suction tube, and a suction device is connected to the suction tube. During use, the pulmonary artery thrombosis removal system is assembled with the aspiration catheter and dilator and then delivered to the thrombus location along the pre-placed guidewire. Once the thrombus location is reached, the dilator is removed. The pulmonary thrombectomy device is delivered to the thrombus site along the guidewire inside the aspiration catheter, and the stent tip of the thrombectomy stent passes through the thrombus. The delivery catheter is retracted, and the thrombectomy stent is released into the thrombus. Then, relative to the exposed release state of the thrombectomy stent and the delivery catheter, the thrombectomy stent and the delivery stent are retracted simultaneously to bring the thrombus into the aspiration catheter. The aspiration catheter is then subjected to negative pressure aspiration using an aspirator to complete the removal of the pulmonary thrombus.