Thrombectomy system for transcatheter pulmonary artery embolization

Abstract

The present application belongs to the field of medical devices, and relates to a thrombus extraction system for transcatheter pulmonary artery embolization, comprising a suction catheter assembly and a delivery thrombus extraction assembly, the suction catheter assembly establishing a delivery channel for the delivery thrombus extraction assembly; the delivery thrombus extraction assembly comprising a thrombus extractor, a guide sheath and a control handle, the guide sheath being fixed with the control handle, the thrombus extractor being threaded out of the guide sheath and being controlled by the control handle; the thrombus extractor comprising a push tube, a connecting tube and a mesh disc, the push tube being sleeved on the outer periphery of the connecting tube, the mesh disc being connected and fixed with a head end guide of the connecting tube at a distal end, and being connected and fixed with a head end of the push tube at a proximal end, and the distal end and the proximal end of the mesh disc are both provided with a developing ring, and the push tube and the connecting tube are respectively connected with the control handle. The mesh disc diameter is controllable, more complex blood vessels can be compatible, the operability is strong during the operation process, the thrombus extraction system is avoided from being replaced halfway due to the mismatch between the stent and the blood vessel, the operation time is shortened, and the thrombus extraction operation of the patient can be better completed.

Description

Technical Field

[0001] This invention relates to a thrombectomy system for transcatheter pulmonary embolism, belonging to the field of medical devices. Background Technology

[0002] Acute pulmonary embolism (PE) is a common cardiovascular disease in my country. It is a clinical and pathophysiological syndrome caused by endogenous or exogenous emboli obstructing the pulmonary artery, leading to pulmonary circulatory disturbances. It is often caused by the detachment of thrombi from deep vein thrombosis in the lower extremities. It has a high mortality rate and seriously endangers patients' health and quality of life. Pulmonary thromboembolism is the most common type of acute pulmonary embolism (PE), and deep vein thrombosis is the main source of thrombi causing pulmonary thromboembolism.

[0003] Acute pulmonary embolism (API) is an acute, progressive disruption of pulmonary circulation, primarily manifesting as shortness of breath, chest tightness, and even death. Current clinical research indicates a high mortality rate for API. The main treatment for API is surgery, and timely intervention after onset is crucial to prevent recurrence and potential death.

[0004] Traditional surgical treatments for pulmonary embolism primarily involve open thrombectomy and pulmonary endarterectomy, but these methods are highly invasive. With advancements in medical technology, endovascular therapy has become an effective and important treatment for acute pulmonary embolism. Common treatment methods include guidewire catheter-based thrombectomy, thrombectomy, and endovascular thrombolysis. However, using existing instruments alone is not ideal for removing large pulmonary thrombi, while using multiple surgical methods results in complex procedures, longer operation times, and higher costs.

[0005] Patent CN114831698A discloses a double-layered thrombectomy stent. This device consists of a distal filtering disc, a proximal retrieval disc, and at least one intermediate thrombectomy disc, all coaxially connected in sequence. This structure has a large cross-sectional area in its contracted state, thus often requiring a large sheath diameter for the delivery device. Such a delivery device is unsuitable for cases with tortuous access routes and complex lesion structures. Furthermore, the double-layered stent exhibits significant radial support, leading to high pressure on the blood vessel. Patent CN112089477A discloses a thrombectomy stent that uses adjusted mesh density to capture small thrombi escaping to distal vessels. However, due to the gradient decrease in diameter from proximal to distal intermediate thrombectomy discs, the structure does not adhere well to the vessel wall, failing to adequately capture small thrombi and posing a risk of escape. Summary of the Invention

[0006] The technical problem to be solved by the present invention is to propose a thrombectomy system for transcatheter pulmonary embolism. The thrombectomy system for transcatheter pulmonary embolism has a controllable mesh diameter, can be compatible with more complex blood vessels, has strong operability during the operation, avoids the need to change the thrombectomy system midway due to stent and blood vessel mismatch, shortens the operation time, and can better cooperate with the patient to complete the thrombectomy operation.

[0007] The thrombectomy system for transcatheter pulmonary embolism of the present invention includes an aspiration catheter assembly and a delivery thrombectomy assembly. The aspiration catheter assembly establishes a delivery channel for the delivery thrombectomy assembly. The delivery thrombectomy assembly includes a thrombectomy device, an inlet sheath, and a control handle. The inlet sheath is fixed to the control handle, and the thrombectomy device extends out of the inlet sheath and is controlled by the control handle. The thrombectomy device includes a push tube, a connecting tube, and a mesh tray. The push tube is sleeved around the periphery of the connecting tube. The distal end of the mesh tray is connected and fixed to the guide head at the tip of the connecting tube, and the proximal end of the mesh tray is connected and fixed to the tip of the push tube. Both the distal and proximal ends of the mesh tray are provided with contrast rings. The push tube and the connecting tube are respectively connected to the control handle.

[0008] During use, a delivery channel is established through the aspiration catheter assembly based on the determined thrombectomy location. The guide sheath is inserted into the blood vessel through the aspiration catheter assembly. Then, the diameter of the mesh disc is gradually increased by adjusting the control handle until it completely conforms to the vessel wall. During adjustment, only the relative position between the push tube and the connecting tube needs to be adjusted. Adjusting the mesh disc diameter according to actual application allows for better conformation to the vessel wall, minimizing pressure on the vessel. The controllable diameter of the mesh disc can cover vessels from 5mm to 30mm. The mesh disc size is easily adjustable, accommodating more complex vessels, and offering high operability during surgery. This avoids the need to change the thrombectomy system mid-operation due to stent-vessel mismatch, thus shortening the operation time. The guide head is the TIP guide head.

[0009] Preferably, the control handle includes a grip handle one and a grip handle two. The inlet sheath is fixedly connected to the inside of the grip handle one. A rotating handle one is provided between the grip handle one and the grip handle two, and the rotating handle one is rotatably connected to both grip handle one and grip handle two respectively. The inner wall of the rotating handle one is connected to the push tube via a threaded drive. The rear end of the grip handle two is rotatably connected to the rotating handle two, and the inner wall of the rotating handle two is connected to the connecting tube via a threaded drive. A Luer connector is connected to the tail end of the rotating handle two. In specific operation, the rotating handle two and the rotating handle one can be rotated simultaneously. The rotating handle two and the rotating handle one drive the connecting tube and the push tube to move through the threaded drive, so that the connecting tube drives the push tube and the mesh tray into the blood vessel along the inlet sheath. Then, rotating the rotating handle one changes the relative position of the push tube and the connecting tube, thereby adjusting the diameter of the mesh tray. When the patient's blood vessel diameter is small, the push tube can be adjusted backward to increase the distance between the two contrasting rings and decrease the diameter of the mesh tray. When the patient's blood vessel diameter is relatively large, the push tube can be pushed forward to decrease the distance between the two contrasting rings and increase the diameter of the mesh tray.

[0010] Preferably, the grip handle has a fixed sheath connector inside, which has a stepped hole. A guide sheath is inserted into the larger end of the stepped hole and fixed to the fixed sheath connector. The push tube and the connecting tube extend from the smaller end of the stepped hole, and the smaller end of the stepped hole is connected to the hemostatic valve through the connecting tube. After the mesh tray, push tube, and connecting tube reach the designated position, heparinized saline and contrast agent are injected through the hemostatic valve. The heparinized saline and contrast agent enter the guide sheath through the smaller end of the stepped hole of the fixed sheath connector and finally reach the lesion site through the guide sheath.

[0011] Preferably, the rear end of the fixed sheath connector is connected to a screw cap via a thread, and a sealing ring is provided between the screw cap and the fixed sheath connector to prevent blood from seeping out of the inlet sheath during the operation and reduce blood loss.

[0012] Preferably, the aspiration catheter assembly includes an aspiration tube, one end of which is connected to a connector, and the connector is connected to a second hemostatic valve. The thrombus in the blood vessel is drawn out through the aspiration tube, the connector, and the second hemostatic valve, thus effectively removing large pulmonary emboli and small escaped thrombi.

[0013] Preferably, the braiding density at the distal end of the mesh is greater than that at the proximal end. The lower braiding density at the proximal end allows for the cutting of large thrombi; the higher braiding density at the distal end filters and intercepts broken thrombi to prevent them from escaping and blocking distal blood vessels, while also allowing most of the thrombi to be drawn back into the aspiration tube for removal from the body.

[0014] Preferably, the distal end of the mesh disc is sutured or covered with a polymer membrane, which can filter and intercept broken thrombi to prevent them from escaping and blocking distal blood vessels, and at the same time can also draw most of the thrombi back into the suction tube and remove them from the body.

[0015] Preferably, the mesh disc is made of super-elastic memory material or expandable polymer fiber electrospun and woven, serving as a thrombus protection device to prevent thrombi from escaping to distal sites and minimize secondary embolic events. The mesh disc is pear-shaped, and the diameter of the braided filaments is 0.08mm-0.15mm.

[0016] Preferably, the screen contains at least two or more developing fibers, which are woven together in a cross pattern on the screen. The developing fibers can be platinum-based, platinum-tungsten, DFT, etc.

[0017] Preferably, the near end of the mesh disk is heat-fused to the push tube, and the far end of the mesh disk is connected to the connecting tube and the guide head by riveting, heat fusion or adhesive.

[0018] The beneficial effects of this invention compared to the prior art are:

[0019] This invention features a simple and rationally designed structure with a controllable mesh diameter, accommodating a wider range of complex blood vessels. It offers high operability during surgery, avoiding the need to change the thrombectomy system mid-operation due to stent-vessel mismatch, thus shortening surgical time. It effectively facilitates the removal of large pulmonary emboli and escaped small thrombi, providing an efficient, safe, and non-invasive method for thrombus removal. The distal mesh has a higher weaving density than the proximal mesh, which filters and intercepts broken thrombi to prevent them from escaping and blocking distal vessels, minimizing secondary embolic events. Attached Figure Description

[0020] Figure 1 This is a schematic diagram of a thrombectomy system used for transcatheter pulmonary embolism;

[0021] Figure 2 This is a schematic diagram of the thrombus delivery and thrombus removal assembly.

[0022] Figure 3 This is a schematic diagram of the suction catheter assembly structure;

[0023] Figure 4 This is a schematic diagram of the thrombectomy device;

[0024] Figure 5 This is a schematic diagram of the structure at the sheath joint;

[0025] Figure 6 This is a schematic diagram of a screw thread drive structure;

[0026] Figure 7 This is a diagram showing the state of the thrombectomy device as it is released into the blood vessel.

[0027] Figure 8 This is a diagram showing the state of the thrombectomy device after adjusting the mesh diameter according to the condition of the blood vessel.

[0028] Figure 9 This is a diagram illustrating the density of data storage at the remote and near ends of the cloud drive.

[0029] Figure 10 This is a schematic diagram of the interlacing of the developing wire and the screen.

[0030] In the diagram: 1. Control handle; 2. Aspiration catheter assembly; 3. Thrombus retriever; 4. Introducing sheath; 5. Wire tray; 6. Handle 1; 7. Rotary handle 1; 8. Handle 2; 9. Rotary handle 2; 10. Luer connector; 11. Hemostatic valve 1; 12. Aspiration tube; 13. Connector seat; 14. Hemostatic valve 2; 15. Connecting tube; 16. Push tube; 17. Guide head; 18. Contrast ring; 19. Sheath connector; 20. Sealing ring; 21. Cap; 22. Contrast wire; 23. Thread; 24. Blood vessel. Detailed Implementation

[0031] The present invention will now be further described with reference to the accompanying drawings:

[0032] like Figures 1-10 The thrombectomy system for transcatheter pulmonary embolism of the present invention includes an aspiration catheter assembly 2 and a delivery thrombectomy assembly. The aspiration catheter assembly 2 establishes a delivery channel for the delivery thrombectomy assembly. The delivery thrombectomy assembly includes a thrombectomy device 3, an inlet sheath 4, and a control handle 1. The inlet sheath 4 is fixed to the control handle 1. The thrombectomy device 3 passes through the inlet sheath 4 and is controlled by the control handle 1. The thrombectomy device 3 includes a push tube 16, a connecting tube 15, and a mesh tray 5. The push tube 16 is sleeved on the outer periphery of the connecting tube 15. The distal end of the mesh tray 5 is connected and fixed to the guide head 17 at the head end of the connecting tube 15. The proximal end of the mesh tray 5 is connected and fixed to the head end of the push tube 16. Both the distal and proximal ends of the mesh tray 5 are provided with contrast rings 18. The push tube 16 and the connecting tube 15 are respectively connected to the control handle 1.

[0033] In this embodiment:

[0034] The control handle 1 includes a grip handle 6 and a grip handle 8. The guide sheath 4 is fixedly connected to the grip handle 6. A rotating handle 7 is provided between the grip handle 6 and the grip handle 8. The rotating handle 7 is rotatably connected to the grip handle 6 and the grip handle 8 respectively, and the inner wall of the rotating handle 7 is connected to the push tube 16 by a thread 23. The rear end of the grip handle 8 is rotatably connected to a rotating handle 9. The inner wall of the rotating handle 9 is connected to the connecting tube 15 by a thread 23. The tail end of the rotating handle 9 is connected to a Luer connector 10. In specific operation, the rotating handle 9 and the rotating handle 7 can be rotated simultaneously. The rotating handle 9 and the rotating handle 7 drive the connecting tube 15 and the push tube 16 to move through the thread 23. The connecting tube 15 drives the push tube 16 and the mesh tray 5 to enter the blood vessel 24 along the guide sheath 4. Then, the rotating handle 7 is rotated to change the relative position of the push tube 16 and the connecting tube 15, thereby adjusting the diameter of the mesh tray 5. When the diameter of the patient's blood vessel 24 is small, the push tube 16 can be adjusted backward to increase the distance between the two imaging rings 18 and decrease the diameter of the mesh 5; when the diameter of the patient's blood vessel 24 is relatively large, the push tube 16 can be pushed forward to decrease the distance between the two imaging rings 18 and increase the diameter of the mesh 5.

[0035] The handle 16 has a fixed sheath connector 19 inside. The fixed sheath connector 19 has a stepped hole, and an inlet sheath 4 is inserted into the larger end of the stepped hole. The inlet sheath 4 is fixed to the fixed sheath connector 19. The push tube 16 and the connecting tube 15 pass through the smaller end of the stepped hole. One side of the smaller end of the stepped hole is connected to the hemostatic valve 11 through the connecting tube 15. After the mesh tray 5, the push tube 16, and the connecting tube 15 reach the designated position, heparinized saline and contrast agent are injected through the hemostatic valve 11. The heparinized saline and contrast agent enter the inlet sheath 4 through the smaller end of the stepped hole of the fixed sheath connector 19 and finally reach the lesion site through the inlet sheath 4.

[0036] The rear end of the fixed sheath connector 19 is connected to a screw cap 21 via a thread, and a sealing ring 20 is provided between the screw cap 21 and the fixed sheath connector 19 to prevent blood from seeping out of the inlet sheath during the operation and reduce blood loss.

[0037] The suction catheter assembly 2 includes a suction tube 12, one end of which is connected to a connector 13. The connector 13 is connected to a second hemostatic valve 14. The thrombus in the blood vessel 24 is extracted through the suction tube 12, connector 13 and second hemostatic valve 14, thus effectively removing large pulmonary embolism thrombi and escaped small thrombi.

[0038] The distal braiding density of the mesh disk 5 is greater than that of the proximal braiding density. The lower braiding density of the proximal braiding density of the mesh disk 5 allows for the cutting of large thrombi; the higher braiding density of the distal braiding density of the mesh disk 5, or the distal braiding density of the mesh disk 5 being sutured (PET) or covered with (ePTFE) polymer membrane, is used to filter and intercept broken thrombi to prevent them from escaping and blocking distal blood vessels 24. At the same time, it can also draw most of the thrombi back into the aspiration tube 12 for removal from the body.

[0039] The mesh disc 5 is made of super-elastic memory material or expandable polymer fiber electrospun and woven, acting as a thrombus protection device to prevent thrombi from escaping to distal sites and minimize secondary embolic events. The mesh disc 5 is pear-shaped, with braided filaments ranging from 0.08mm to 0.15mm in diameter. Super-elastic memory material can be made of materials such as NIT (nickel-titanium alloy), and expandable polymer fibers can be made of materials such as SMP.

[0040] The stencil 5 includes at least two strands of developing wire 22, which are cross-woven onto the stencil 5. The developing wire 22 can be made of platinum, platinum-tungsten, DFT, etc.; the developing wire can directly replace a corresponding number of stencil braiding wires (e.g., nickel-titanium alloy wire), or it can be directly wound onto the stencil braiding wires (e.g., nickel-titanium alloy wire), achieving both developing and maintaining the elasticity of the stencil 5. The proximal end of the stencil 5 is heat-fused to the push tube 16, and the distal end of the stencil 5 is connected to the connecting tube 15 and the guide head 17 by riveting, heat fusion, or adhesive.

[0041] In use, based on the determined thrombectomy location, a delivery channel is established through the aspiration catheter assembly 2. The insertion sheath 4 is inserted into the blood vessel 24 through the aspiration catheter assembly 2. Then, the diameter of the mesh disc 5 is gradually increased by adjusting the control handle 1 until it completely conforms to the wall of the blood vessel 24. During the adjustment process, only the relative position between the push tube 16 and the connecting tube 15 needs to be adjusted. Adjusting the diameter of the mesh disc 5 according to the actual application situation can better conform to the wall of the blood vessel 24, reduce pressure on the blood vessel 24, and the controllable diameter of the mesh disc 5 can cover blood vessels 24 from 5mm to 30mm. The size of the mesh disc 5 is easy to adjust, which can accommodate more complex blood vessels 24. It has high operability during the operation and avoids the need to change the thrombectomy system due to the mismatch between the stent and the blood vessel 24, thus shortening the operation time. The guide head 17 is the TIP guide head 17.

Claims

1. A thrombectomy system for transcatheter pulmonary embolism, characterized in that: The device includes an aspiration catheter assembly (2) and a delivery thrombectomy assembly. The aspiration catheter assembly (2) establishes a delivery channel for the delivery thrombectomy assembly. The delivery thrombectomy assembly includes a thrombectomy device (3), an inlet sheath (4), and a control handle (1). The inlet sheath (4) is fixed to the control handle (1). The thrombectomy device (3) passes through the inlet sheath (4) and is controlled by the control handle (1). The thrombectomy device (3) includes a push tube (16), a connecting tube (15), and a mesh tray (5). The push tube (16) is sleeved around the outer periphery of the connecting tube (15). The distal end of the mesh tray (5) is connected and fixed to the guide head (17) at the head end of the connecting tube (15). The proximal end of the mesh tray (5) is connected and fixed to the head end of the push tube (16). The diameter of the mesh tray is adjusted according to the actual application. The distal and proximal ends of the mesh tray (5) are provided with imaging rings (18). The push tube (16) and the connecting tube (15) are respectively connected to the control handle (1). The control handle (1) includes a grip handle one (6) and a grip handle two (8). The guide sheath (4) is fixedly connected to the inside of the grip handle one (6). A rotating handle one (7) is provided between the grip handle one (6) and the grip handle two (8). The rotating handle one (7) is rotatably connected to the grip handle one (6) and the grip handle two (8) respectively. The inner wall of the rotating handle one (7) is connected to the push tube (16) through the thread (23). The rear end of the grip handle two (8) is rotatably connected to a rotating handle two (9). The inner wall of the rotating handle two (9) is connected to the connecting tube (15) through the thread (23). The tail end of the rotating handle two (9) is connected to a Luer connector (10). The handle (6) has a fixed sheath connector (19) inside. The fixed sheath connector (19) has a stepped hole. An inlet sheath (4) is inserted into the large end of the stepped hole. The inlet sheath (4) is fixed to the fixed sheath connector (19). The push tube (16) and the connecting tube (15) pass through the small end of the stepped hole. The small end of the stepped hole is connected to the hemostatic valve (11) through the connecting tube (15). The rear end of the fixed sheath connector (19) is connected to a screw cap (21) by a thread, and a sealing ring (20) is provided between the screw cap (21) and the fixed sheath connector (19). The aspiration catheter assembly (2) includes an aspiration tube (12), one end of which is connected to a connector (13), and the connector (13) is connected to a hemostatic valve (14).

2. The thrombectomy system for transcatheter pulmonary embolism according to any one of claims 1, characterized in that: The remote compilation density of cloud storage (5) is greater than that of the near compilation density of cloud storage (5).

3. The thrombectomy system for transcatheter pulmonary embolism according to any one of claims 1, characterized in that: (5) The distal end of the mesh disk is sutured or covered with a polymer membrane.

4. The thrombectomy system for transcatheter pulmonary embolism according to any one of claims 1, characterized in that: The network disk (5) is made of super-elastic memory material or expandable polymer fiber electrospinning weaving.

5. The thrombectomy system for transcatheter pulmonary embolism according to any one of claims 1, characterized in that: The screen (5) contains at least two or more developing strands (22), which are woven together in a cross pattern on the screen (5).

6. The thrombectomy system for transcatheter pulmonary embolism according to any one of claims 1, characterized in that: The near end of the network disk (5) is heat-fused to the push tube (16), and the far end of the network disk (5) is connected to the connecting tube (15) and the guide head (17) by riveting, heat fusion or adhesive.

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