Intravascular plugging device

Abstract

The utility model provides an intravascular occluder which comprises an occluder body, a catheter part and a control mechanism, the occluder body is a plurality of frameworks which can be opened to form an umbrella-shaped structure, and a layer of covering is attached to the occluder body; the catheter part is used for accommodating the plugging device and the connecting rod part of the control mechanism; the control mechanism comprises a connecting rod part and a handle control part, and is used for controlling the pushing and withdrawing of the plugging device; after the plugging device is unfolded to completely plug the inner diameter of the blood vessel, the function of cutting off blood flowing can be achieved, a space for blood flowing can be reserved at the position close to the inner wall of the blood vessel by properly retracting the plugging device into the catheter, and the plugging device can be completely retracted into the catheter by completely retracting the plugging device. The utility model has the beneficial effects that unfolding and folding are completely reversible, controllable opening and cutting of blood flow can be realized, complications caused by long-time ischemia of blocked blood vessels can be avoided, and a long-time operation becomes possible.

Description

Technical Field

[0001] The utility model relates to the field of interventional medical devices, in particular to an intravascular occluder. Background Art

[0002] In the prior art, there are two solutions for blocking the inner diameter of blood vessels:

[0003] The first solution uses a balloon, which is inserted through a sheath into the inner diameter of the blood vessel to be blocked, and the balloon is infused and maintained at a certain pressure, so that the balloon expands to block the inner diameter of the blood vessel, thereby cutting off the blood flow in the blood vessel to meet the needs of some surgeries. After the operation is completed, the blood flow can be restored by relieving the pressure of the inflated balloon, and the balloon can be shrunk to withdraw the sheath from the human blood vessel.

[0004] However, there are many complications in this way:

[0005] First, the balloon expansion performance of existing products is limited, and the initial diameter cannot be made very thin, commonly 11-12F (F is the abbreviation of French, 1F≈0.33mm), which is only suitable for blood vessels with larger inner diameters. The thicker the product diameter, the greater the risk of damage to the blood vessels at the puncture site. Some balloons have a thin initial diameter, but their maximum expansion diameter is not large, which limits their use scenarios and cannot effectively block some blood vessels with larger inner diameters.

[0006] Second, it cannot be completely blocked. For patients with plaques on the blood vessel wall, the plaques will not shrink along with the blood vessels, and even a highly compliant balloon cannot guarantee complete fit.

[0007] Third, there is a risk of balloon rupture. In order for the balloon to block the inner diameter of the blood vessel, a certain pressure must be maintained. Due to the manufacturing process of balloon products, there is no perfect way to ensure the balloon's bursting performance, so there is a risk of balloon rupture. Once the balloon ruptures, it may cause blood vessel rupture, and in severe cases, even serious complications such as gas embolism, massive bleeding, and death.

[0008] Another solution is to use a stent with a partial cover to block certain specific blood vessels. The stent is delivered to a designated location in the blood vessel, and the stent is deployed so that the cover attached to the stent covers the side branches of the blood vessel where the stent is located, thereby playing a blocking role. When withdrawing the stent, the stent and the cover are withdrawn into the catheter together by pulling the connecting rod connected to the stent.

[0009] However, this approach has many limitations:

[0010] First, it can only block the side branch vessels, and there must be a main vessel for stent deployment.

[0011] Secondly, even if this type of occlusion can effectively block blood flow, if the operation time is too long and the occlusion must be temporarily lifted to restore blood flow during the process, then this type of occlusion will not be able to meet the needs.

[0012] Therefore, in order to solve the problems of many complications and short operation time in the prior art, it is urgently necessary to provide an intravascular occluder with a small initial diameter, reversible deployment and folding process, and controllable deployment area. Utility Model Content

[0013] The utility model aims to solve the problems of many complications and short operation time in existing methods, and provides an intravascular occluder with a small initial diameter, reversible expansion and folding processes, and controllable expansion area.

[0014] In order to achieve this purpose, the utility model provides an intravascular occluder, including an occluder, a catheter part and a control mechanism. The occluder is a plurality of skeletons that can be expanded to form an umbrella-like structure, and a layer of covering material is attached; the end of the occluder that can be expanded is called the distal end, and the other end is called the proximal end; the catheter part is connected to the control mechanism, which is used to store the occluder and the connecting rod part of the control mechanism; the control mechanism includes a connecting rod part and a handle control part, which controls the pushing and retraction of the occluder; the distal end of the connecting rod part is connected to the proximal end of the occluder, and the proximal end of the connecting rod part is connected to the handle control part; after being expanded to completely block the inner diameter of the blood vessel, it can play the role of cutting off blood flow, and appropriately retracting the occluder into the catheter can leave space for blood flow near the inner wall of the blood vessel, and complete recovery can return all the occluders to the catheter.

[0015] The occluder uses nickel-titanium alloy as the skeleton, with 3-36 skeletons. The cross-sectional area of ​​the skeleton is 0.1-6 square millimeters, and the length of the skeleton ranges from 2-20 mm. The skeleton is streamlined and uniform, and the size of the distal end of the skeleton is slightly smaller than the proximal end of the skeleton to reduce the disturbance of blood flow to the occluder.

[0016] The covering of the occluder is one-piece or multi-piece, and is manufactured by electrospinning or dipping. The thickness of the covering ranges from 5 to 100 μm.

[0017] The catheter part has a certain hardness, and the outer diameter of the catheter remains basically unchanged when the occluder is deployed and recovered. The catheter can move smoothly in the blood vessel and can be adjusted. The catheter part has one or more lumens; the catheter has reserved lumens / holes for the use of developer. There are multiple catheter marks on the catheter part to indicate the length of the distal end of the catheter entering the blood vessel. The catheter part uses a braiding process or a spring winding process to strengthen it.

[0018] The deployment and recovery process of the occluder is reversible. The control mechanism has an indication function, indicating that the occluder is fully recovered, partially deployed, partially recovered, and fully deployed.

[0019] The handle control part includes: a pressure block, a handle, a knob, a cover and a handle; the proximal end of the catheter part is connected to the handle, and the proximal end of the connecting rod part is connected to the pressure block; the handle is connected to the knob; the cover is connected to the handle; there is a channel with a changing cross-section in the handle, which allows the connecting rod, the pressure block and the handle to pass through and move in sequence from the distal end to the proximal end; there is a channel in the handle, the diameter of which is slightly larger than that of the pressure block, and the distal part of the handle is an internal thread, which engages with the external thread of the pressure block; the pressure block is a structure with flattened sides of a cylinder and an external thread on the arc side, which converts the rotation of the handle into axial forward and backward movement; the cover is installed at the tail end of the handle to limit the axial freedom of the handle; the cover is hollow, allowing the connection between the handle and the knob to pass through and rotate in it.

[0020] The beneficial effect of the utility model is that it greatly increases the expansion and contraction ratio of the occluder, that is, the ratio of the maximum expansion diameter to the initial state diameter, which can maximize the occlusion area while minimizing the risk of damaging the inner wall of the blood vessel; in addition, there will be no rupture, which can greatly reduce the impact of vascular plaques. Furthermore, due to the completely reversible characteristics of the expansion and contraction of the utility model, it can achieve controllable opening and cutting of blood flow, avoid complications caused by long-term ischemia of the blocked blood vessels, and make long-term surgery possible.

[0021] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, preferred embodiments are given below and described in detail with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] In order to more clearly illustrate the specific implementation methods of the utility model or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the utility model. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0023] Figure 1A It is a schematic diagram of the utility model in a folded state.

[0024] Figure 1B It is a schematic diagram of the unfolded state of the utility model.

[0025] Figure 2A It is a partially enlarged schematic diagram of the folded state of the utility model.

[0026] Figure 2BIt is a partially enlarged schematic diagram of the unfolded state of the utility model.

[0027] Figure 2C It is a partially enlarged schematic diagram of the folded state of the utility model.

[0028] Figure 3A It is a perspective view of the stowed state control mechanism of the present invention.

[0029] Figure 3B It is a perspective view of the unfolded state control mechanism of the utility model.

[0030] Figure 4A This is a schematic diagram of a stowed state of an embodiment of the utility model.

[0031] Figure 4B The figure is a schematic diagram of a typical occluder of the utility model.

[0032] Figure 4C The utility model is a schematic diagram of an occluder with a cover opening.

[0033] Figure 4D The utility model is a schematic diagram of an occluder with a hole in the connecting rod part.

[0034] Figure 4E The figure is a schematic diagram of an unfolded state of an embodiment of the utility model.

[0035] Figure 5 The figure is a schematic diagram of the skeleton shape of an embodiment of the utility model.

[0036] Figure 6 This is a schematic diagram of a catheter marking according to an embodiment of the present utility model.

[0037] Fig. 7A This is a schematic diagram of a cover structure of an embodiment of the utility model.

[0038] Figure 7B The figure is a schematic diagram of a pressing block structure of an embodiment of the utility model. DETAILED DESCRIPTION

[0039] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only a part of the embodiments of the utility model, rather than all the embodiments. The components of the embodiments of the utility model generally described and shown in the drawings here can be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of the utility model provided in the drawings is not intended to limit the scope of the utility model claimed for protection, but merely represents the selected embodiments of the utility model. Based on the embodiments of the utility model, all other embodiments obtained by those skilled in the art without making creative work belong to the scope of protection of the utility model.

[0040] The present invention is further described in detail below so that those skilled in the art can implement the invention with reference to the description.

[0041] First, please refer to Figure 1A and Figure 1B , Figure 1A is a schematic diagram of the folded state of the utility model, Figure 1B Schematic diagram of the utility model in the unfolded state. Figure 1A and Figure 1B As shown, the intravascular occluder 1 includes three important parts: an occluder 12 , a catheter part 13 and a control mechanism 14 . Figure 1A The occluder is shown in the state of being retracted (not in use). Figure 1B The image shows the occluder being deployed (cutting off blood flow in a blood vessel).

[0042] Then please refer to Figure 2A , Figure 2B and Figure 2C , Figure 2A It is a partially enlarged schematic diagram of the folded state of the utility model. Figure 2B It is a partially enlarged schematic diagram of the unfolded state of the utility model. Figure 2C It is a partially enlarged schematic diagram of the folded state of the utility model. Figure 2A The diagram shows the state of the vascular occluder being retracted (when not in use). In this state, the occluder 12 is in the retracted state 12A and is completely received in the catheter portion 13. In most cases, the distal end 13D of the catheter should exceed the occluder 12 in the axial direction to provide complete covering protection. Figure 2B and Figure 2CThe state of the vascular occluder being deployed (cutting off blood flow) is shown. In this state, the occluder 12 is in the deployed state 12B. The connecting portion 121 of the occluder 12 should be partially or completely received in the catheter portion 13. The skeleton 122 and the covering 123 of the occluder 12 are deployed in the blood vessel to cut off the blood flow. The direction of the blood flow should be from left to right as shown in the embodiment. Placing the device in the opposite direction will also have the effect of cutting off the blood flow, but the effect is generally not as good as the normal direction. The occluding performance is best when the occluder 12 is fully deployed (the skeleton 122 is fully deployed to the maximum, and the covering 123 is opened). When part of the blood flow needs to pass through, the occluder 12 can be appropriately retracted into the catheter portion 13, that is, the skeleton 122 is not fully deployed, so that the occluder 12 creates space with the inner wall of the blood vessel. The connecting portion 121 of the occluder is connected to the distal end 141D of the connecting rod 141.

[0043] Then please refer to Figure 3A and Figure 3B , Figure 3A It is a perspective view of the stowed state control mechanism of the utility model. Figure 3B It is a perspective view of the unfolded state control mechanism of the utility model. Figure 3A It is the state of the control mechanism 14 when the occluder 12 is retracted. Figure 3B It is the state of the control mechanism 14 when the occluder 12 is deployed. The proximal end 13P of the catheter is connected to the handle 143, and the proximal end 141P of the connecting rod 141 is connected to the pressing block 142. The rotary handle 144 is connected to the knob 146. The cover 145 is connected to the handle 143. There is a channel with a changing cross-section in the handle 143, which allows the connecting rod 141, the pressing block 142, and the rotary handle 144 to pass through and move in it from the distal end to the proximal end. There is a channel in the rotary handle 144, the diameter of which is slightly larger than that of the pressing block 142, and the distal end of the rotary handle 144 is an internal thread that meshes with the external thread of the pressing block 142.

[0044] When the device is used, the control mechanism 14 is operated to drive the connecting rod 141 to move forward / backward, and the connecting rod 141 drives the occluder 12 to extend / retract into the catheter part 13, so that the occluder 12 is expanded / retracted in the blood vessel, thereby playing a role in intravascular occlusion with a controllable occlusion area.

[0045] The proximal end 13P of the catheter part 13 is connected to the control mechanism 14, and is used to accommodate the occluder 12 and the connecting rod 141 part of the control mechanism 14. The catheter should have a certain hardness, and the outer diameter of the catheter should remain basically unchanged when the occluder is inside or outside it; the catheter should be able to move smoothly in the blood vessel; the catheter can have adjustable bending performance; the catheter can have one or more lumens; the catheter can have reserved lumens / holes for use of developer; the catheter may use weaving / spring winding and other processes to play a strengthening role.

[0046] Then please refer to Figure 4A , Figure 4B , Figure 4C , Figure 4D and 4E , Figure 4A This is a schematic diagram of a folded state of an embodiment of the utility model. Figure 4B FIG. 1 is a schematic diagram of a typical occluder of the utility model. Figure 4C This is a schematic diagram of an occluder with a cover opening according to the utility model. Figure 4D This is a schematic diagram of an occluder with a hole in a connecting rod portion of the utility model. Figure 4E The figure is a schematic diagram of an unfolded state of an embodiment of the utility model. Figure 4B It is a typical occluder 12, which should be composed of multiple skeletons 122 (the number of skeletons is preferably 3-36, but other numbers can also be used). Fewer skeletons can increase the rigidity of the occluder, but it may not be able to support the inner wall of the blood vessel at multiple points and sacrifice some occluding performance; on the contrary, more skeletons can fit the inner wall of the blood vessel to the greatest extent, but the rigidity decreases and the ability to withstand blood flow impact decreases. Therefore, it is necessary to select a suitable number based on the size of the blocked blood vessel and blood flow data.

[0047] In some embodiments, the occluder 12 may have an opening 126 to reserve a channel for the developer so that the developer can be sprayed during surgery to check the occlusion effect. Figure 4C As shown, the developer can be ejected from the blocked area. If the developer stops at the blocker 12 and does not flow backward, it means that the blockage is complete. The opening can also appear on the connecting portion 121, such as Figure 4D As shown, the developer can be ejected from the blocked area. If the developer does not flow rapidly, it also indicates that the blocking is complete and successful.

[0048] The multi-bone expandable structure of the occluder 12 is not limited to Figure 4B The umbrella-shaped form, Figure 4E This is another embodiment of the occluder 12, showing a form of closing at both ends and opening in the middle. When the control mechanism is used to operate, the expansion and folding of the controllable occlusion area can also be achieved.

[0049] Then please refer to Figure 5 , Figure 5 The skeleton 122 is a schematic diagram of an embodiment of the present invention. The skeleton 122 should be streamlined and uniform, preferably as follows Figure 5As shown, the size of the distal end 122D of the skeleton can be slightly smaller than the proximal end 122P of the skeleton. According to the Bernoulli principle, the flow velocity of the inner wall of the blood vessel is the smallest and the flow velocity of the center is the largest, so this can reduce the disturbance of the blood flow to the occluder 12. The relationship between the skeleton 122 and the connecting portion 121 can be integrated or separated. The shape of the skeleton is streamlined and smoothly transitioned. Preferably, it can be integrally formed by laser cutting of nickel-titanium tubes, and then fixed with a designed mold and heat treated to form a predetermined shape. The skeleton should contact the inner wall of the blood vessel in a smooth and tangential manner as much as possible at the point where it contacts the inner wall of the blood vessel to avoid damage to the inner wall of the blood vessel. Preferably, the occluder can also be surface treated by electrochemical polishing, hydrophilic coating, etc. The size design of the skeleton 122 is a key factor in determining the "expansion and contraction ratio" of the occluder 12. Due to the special design of the utility model, a higher "expansion and contraction ratio" can be easily achieved. The longer the length of the skeleton 122, the larger the maximum diameter that can be expanded, but at the same time, due to the length increase, the rigidity will be correspondingly weakened, and deflection is easy to occur. Preferably, the cross-sectional area of ​​the skeleton is 0.1-6 square millimeters, and the length of the skeleton is 2-20 mm.

[0050] The covering 123 is generally made of polymer materials, but other materials can also be used. It can be a whole piece or multiple pieces spliced ​​together, and its size varies with the size of the frame 122. When the occluder is in the retracted state 12A, the covering 123 needs to be able to be completely stored in the frame 122, and can be folded, squeezed, etc. Therefore, the covering is preferably made of a material with good elasticity, and needs to be as thin as possible, preferably 5-100 μm.

[0051] The covering 123 needs to be connected to the frame 122 to ensure that the covering 123 does not fall off the frame 122 when impacted by blood flow. The connection method can be bonding, welding, etc. Preferably, each frame should have 1-2 contact points with the covering it contacts. If the covering is multi-piece, the connection points with the frame should be appropriately increased.

[0052] Then please refer to Figure 6 , Figure 6 FIG. 1 is a schematic diagram of a catheter marking of an embodiment of the present utility model. Figure 6 As shown, the length of the catheter portion 13 is determined by actual use requirements. There are multiple catheter markings 132 on the catheter 13, which can be used to indicate the length of the catheter distal end 13D entering the blood vessel.

[0053] Then please refer to Fig. 7A , Fig. 7ASchematic diagram of a cover structure of an embodiment of the utility model. As shown in FIG7 , the cover 145 is installed at the tail end of the handle 143 to limit the axial freedom of the knob 144. The cover 145 is hollow, allowing the connection between the knob 144 and the knob 146 to pass through and rotate therein.

[0054] Then please refer to Figure 7B , Figure 7B FIG. 1 is a schematic diagram of a block structure of an embodiment of the utility model. Figure 7B As shown, the pressure block 142 is a cylindrical structure with flattened sides (the channel that the handle 143 cooperates with is also of such a cross-sectional shape, thereby limiting the rotational freedom of the pressure block 142 and the connecting rod 141), and the arc edge has an external thread to convert the rotation of the handle 144 into axial forward and backward movement.

[0055] When operating the control mechanism 14, the knob 146 is rotated, and the knob 146 drives the handle 144 to rotate together. The rotation of the handle 144 drives the pressing block 142 and the connecting rod 141 to move axially in the corresponding channel of the handle 143 (in this embodiment, the distal end surface of the pressing block channel of the handle 143 and the distal end surface of the cover 145 provide axial movement limits for the pressing block 142). The connecting rod 141 transmits the axial displacement to the occluder 12 (the distal end 141D of the connecting rod is connected to the occluder connecting part 121), so that the occluder 12 is pushed out of the catheter part 13 and gradually unfolded in the blood vessel. The occluder 12 can be retracted by rotating the knob 146 in the opposite direction, and the whole process is controllable and reversible.

[0056] In some other embodiments, the control mechanism 14 can be driven by various means such as gears, electromagnetic force, etc., and can be powered manually or actively. The control mechanism 14 can have an indication function, indicating that the occluder is completely retracted, partially opened / deployed (partially retracted), and completely opened / deployed. The indication of partial deployment can be quantitative or qualitative, and can be achieved by providing a scale, an occluder deployment diameter, etc.

[0057] Although the embodiments of the present invention have been disclosed above, they are not limited to the applications listed in the specification and the embodiments. It can be fully applied to various fields suitable for the present invention. For those familiar with the art, additional modifications can be easily realized. Therefore, without departing from the general concept defined by the claims and the scope of equivalents, the present invention is not limited to the specific details and the illustrations shown and described here.

Claims

1. An intravascular occluder, comprising an occluder, a catheter portion and a control mechanism, characterized in that: The occluder is composed of multiple frames that can be expanded to form an umbrella-like structure, and is attached with a layer of covering; the end of the occluder that can be expanded is called the distal end, and the other end is called the proximal end; the catheter part is connected to the control mechanism, which is used to accommodate the occluder and the connecting rod part of the control mechanism; the control mechanism includes a connecting rod part and a handle control part, which control the pushing and retraction of the occluder; the distal end of the connecting rod part is connected to the proximal end of the occluder, and the proximal end of the connecting rod part is connected to the handle control part; after being expanded to completely block the inner diameter of the blood vessel, it can cut off the blood flow, and properly retracting the occluder into the catheter can leave space for blood flow near the inner wall of the blood vessel, and complete retrieval can put the occluder back into the catheter.

2. An intravascular occluder according to claim 1, characterized in that The occluder uses nickel-titanium alloy as a skeleton.

3. The intravascular occluder according to claim 1, characterized in that The number of skeletons of the occluder is 3-36.

4. The intravascular occluder according to claim 1, characterized in that The cross-sectional area of ​​the skeleton is 0.1-6 square millimeters, and the length of the skeleton is 2-20 mm.

5. The intravascular occluder according to claim 1, characterized in that The skeleton has a uniform streamline shape, and the size of the distal end of the skeleton is smaller than that of the proximal end of the skeleton, so as to reduce the disturbance of blood flow to the occluder.

6. The intravascular occluder according to claim 1, characterized in that The covering of the occluder is integral or composed of multiple pieces.

7. The intravascular occluder according to claim 1, characterized in that The covering of the occluder is manufactured by an electrostatic spinning process or a dipping process.

8. The intravascular occluder according to claim 1, characterized in that The thickness of the covering material is in the range of 5-100 μm.

9. The intravascular occluder according to claim 1, characterized in that The catheter part has a certain hardness, and the outer diameter of the catheter remains substantially unchanged when the occluder is in the unfolded and recovered state.

10. The intravascular occluder according to claim 1, characterized in that The catheter can move smoothly in the blood vessel and can be adjusted to bend.

11. The intravascular occluder according to claim 1, characterized in that The catheter part has one or more cavities; the catheter has reserved cavities / holes for use by the developer.

12. The intravascular occluder according to claim 1, characterized in that The catheter is provided with a plurality of catheter marks for indicating the length of the distal end of the catheter entering the blood vessel.

13. The intravascular occluder according to claim 1, characterized in that The catheter part is reinforced by using a braiding process or a spring winding process.

14. The intravascular occluder according to claim 1, characterized in that The deployment and recovery process of the occluder is reversible.

15. The intravascular occluder according to claim 1, characterized in that The control mechanism has an indication function, indicating that the occluder is fully retracted, partially deployed, partially retracted, and fully deployed.

16. The intravascular occluder according to claim 1, characterized in that The handle control part includes: a pressure block, a handle, a knob, a cover and a handle; the proximal end of the catheter part is connected to the handle, and the proximal end of the connecting rod part is connected to the pressure block; the handle and the knob are connected; the cover is connected to the handle; there is a channel with a changing cross-section in the handle, which allows the connecting rod, the pressure block and the handle to pass through and move in sequence from the distal end to the proximal end; there is a channel in the handle, the diameter of which is larger than that of the pressure block, and the distal part of the handle is an internal thread, which engages with the external thread of the pressure block; the pressure block is a structure with flattened sides of a cylinder and an external thread on the arc side, which converts the rotation of the handle into axial forward and backward movement; the cover is installed at the tail end of the handle to limit the axial freedom of the handle; the cover is hollow, allowing the connection between the handle and the knob to pass through and rotate in it.

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