A balloon expandable endovascular stent

Abstract

This utility model belongs to the field of balloon dilation catheter technology, and particularly relates to an internally restrained balloon dilation catheter. It includes a catheter assembly with a first inlet and a second inlet; an inner tube coaxially inserted inside the catheter assembly, with its distal end extending to the outer side of the distal end of the catheter assembly and forming a tip; the proximal end of the inner tube communicating with the first inlet to form a guidewire lumen; a balloon connected to the distal end of the catheter assembly, with its inner lumen communicating with the second inlet to form a pressure chamber; and an elastic restraint assembly having a compressed state and an inflated state. In the inflated state, the elastic restraint assembly is a tubular structure, with the balloon surrounding it, and the elastic restraint assembly fixedly connected to the inner wall of the balloon. Structurally, this dilation catheter retains the unique occipital and groove design of the balloon to leverage its unique advantages in treating vascular stenosis, and the elastic restraint assembly is internally placed inside the balloon, thereby avoiding the risk of the elastic restraint assembly damaging the blood vessel.

Description

Technical Field

[0001] This utility model belongs to the field of balloon dilation catheter technology, and particularly relates to an internally restrained balloon dilation catheter. Background Technology

[0002] Over the past two decades, the global burden of cardiovascular disease has continued to increase. According to relevant research, in 2019, the number of people suffering from cardiovascular disease worldwide reached 523 million, and the number of deaths from cardiovascular disease reached 18.6 million. In China, cardiovascular disease accounts for more than 40% of all deaths. Among various cardiovascular diseases, atherosclerotic cardiovascular disease accounts for more than 60% of all cardiovascular disease deaths.

[0003] Atherosclerosis begins with damage to the vascular intima caused by mechanical stress or biochemical irritation. This induces a large number of white blood cells to migrate to the damaged intima, where they transform into foam cells and are responsible for engulfing fatty substances. Simultaneously, smooth muscle cells migrate from the arterial media to the arterial intima and begin to proliferate. Fat-laden cells, smooth muscle cells, and other substances (such as connective tissue, cholesterol crystals, and calcium) accumulate here, eventually forming plaque-like deposits, known as atherosclerotic plaques. As these plaques gradually enlarge and protrude into the arterial vessels, they can cause narrowing or blockage of the arteries, affecting normal blood flow.

[0004] Currently, percutaneous transluminal angioplasty (PTA) using balloon dilatation catheters has become an important method for treating atherosclerotic diseases. This treatment method involves inflating a high-pressure balloon, which stretches the blood vessel wall and breaks up atherosclerotic plaques, thereby reducing vessel wall tension and widening the narrowed blood vessel lumen. However, when using ordinary balloon dilatation catheters to dilate narrowed arteries, it often causes tearing of the intima in the narrowed area, leading to varying degrees of vascular dissection. In severe cases, stent implantation may be necessary to salvage the condition.

[0005] In view of the aforementioned shortcomings of conventional balloon dilation catheters, existing technology has developed a restraint-type balloon dilation catheter, which improves upon conventional balloons by constructing a wire restraint assembly on the outside of the balloon. When the balloon is inflated, the wire restraint assembly segments the balloon into a series of occipital portions and grooves. The occipital portion of the balloon applies pressure to the lesion site, creating a micro-dissection, thereby achieving effective dilation; while the grooves buffer stress, preventing further dissection, thus reducing vascular damage and the occurrence of dissection to a certain extent.

[0006] However, the wire of a restraint-type balloon dilation catheter is located outside the balloon, which exposes several problems when used to dilate vascular stents or vessels with severe calcification. In severe calcification, the passage rate of the external wire is significantly reduced, and the frictional resistance between the wire and the calcified plaque is 2-3 times higher than that of a regular balloon, greatly limiting the balloon's passage. When dealing with vessels with severe calcification, restraint-type balloon dilation catheters struggle to pass smoothly through the lesion site. Furthermore, during clinical procedures, there is a risk of the wire becoming stuck during catheter withdrawal, potentially causing the balloon to detach from the wire restraint assembly or even break. This significantly limits the application range of restraint-type balloon dilation catheters.

[0007] In addition, the design of the balloon with external metal wires means that the external metal wires and other restraint elements will directly contact the blood vessel wall, which will cause significant damage to the intima and further increase the degree of restenosis at the damaged site.

[0008] Based on this, the present invention provides a novel built-in constraint balloon dilation catheter to overcome the above-mentioned defects. Utility Model Content

[0009] The purpose of this invention is to provide an internally restrained balloon dilatation catheter. On the one hand, the internally restrained balloon dilatation catheter retains the unique occipital and groove design of the balloon in terms of structure to give full play to its unique advantages in treating vascular stenosis. On the other hand, the elastic restraint component is built into the balloon, thereby avoiding the risk of the elastic restraint component damaging the blood vessel.

[0010] This utility model adopts the following technical solution: a built-in constraint balloon dilation catheter, comprising:

[0011] The catheter assembly has a first inlet and a second inlet;

[0012] The inner tube is coaxially inserted inside the catheter assembly. The distal end of the inner tube extends to the outside of the distal end of the catheter assembly and forms a tip. The proximal end of the inner tube communicates with the first inlet to form a guidewire lumen.

[0013] A balloon, the balloon being connected to the distal end of the catheter assembly, the inner lumen of the balloon communicating with the second inlet to form an inflation chamber;

[0014] An elastic restraint assembly has a compressed state and an inflated state. In the inflated state, the elastic restraint assembly is a tubular structure. The balloon surrounds the elastic restraint assembly, and the elastic restraint assembly is fixedly connected to the inner wall of the balloon.

[0015] Furthermore, when the outer diameter of the distal end of the balloon is equal to the outer diameter of the proximal end of the balloon, the elastic constraint assembly as a whole has the same preset deformation capacity.

[0016] As the outer diameter of the balloon gradually increases or decreases from the distal end to the proximal end, the pre-deformation capability of the elastic constraint component gradually increases or decreases synchronously from the distal end to the proximal end along the axial direction of the catheter assembly.

[0017] Furthermore, the elastic constraint component includes multiple parallel first-direction constraint members and multiple parallel second-direction constraint members. The first-direction constraint members and the second-direction constraint members are interwoven or connected at a preset angle to form multiple mesh holes. When the balloon is inflated, the outer surface of the balloon is restricted by the mesh holes, and a portion of the balloon protrudes outward from the mesh holes to form a occipital region.

[0018] Furthermore, the first directional constraint is disposed along the axial direction of the conduit assembly.

[0019] Furthermore, when the balloon expands, the shape of the mesh is one or more of the following: rectangular, rhomboid, parallelogram, and regular hexagon.

[0020] Furthermore, when the balloon expands, the height of the occipital region is 0.01mm-1mm.

[0021] Furthermore, the first directional constraint member is composed of multiple interconnected and spaced-apart bent segments;

[0022] When the outer diameter of the distal end of the balloon is equal to the outer diameter of the proximal end of the balloon, the number of bending segments or the bending radius in each segment of the first directional constraint member are the same.

[0023] As the outer diameter of the balloon gradually increases or decreases from the distal end to the proximal end, the number of bending segments or the bending arc of the first directional constraint member from the distal end to the proximal end gradually increases or decreases synchronously.

[0024] Furthermore, the second directional constraint is divided into multiple bending units, and the ends of the multiple bending units are connected sequentially to form a ring-shaped second directional constraint.

[0025] The bending units are all fixedly connected to the first directional constraint member.

[0026] Furthermore, when the outer diameter of the distal end of the balloon is equal to the outer diameter of the proximal end of the balloon, the number of bending units or the bending radius of the second directional constraint member are the same.

[0027] As the outer diameter of the balloon gradually increases or decreases from the distal end to the proximal end, the number of bending units or the bending radius of the second directional constraint member gradually increases or decreases synchronously from the distal end to the proximal end.

[0028] Furthermore, the bending unit is a horizontally arranged "Ω" shaped structure, wherein the vertical part is fixedly connected to the first direction constraint member.

[0029] Compared with the prior art, the beneficial effects of this utility model are as follows:

[0030] When in use, the balloon expands as it inflates, which in turn causes the elastic restraint component to expand. Once it reaches a certain outer diameter, the elastic restraint component can no longer expand, but the balloon can continue to expand. The local structure of the balloon will protrude from the restraint of the elastic restraint component to form a occipital region, while the part of the balloon restrained by the elastic restraint component forms a groove, thus making the outer surface of the balloon present a groove and an occipital region.

[0031] In this invention, the built-in restraint balloon dilation catheter places the elastic restraint component inside the balloon cavity, avoiding direct contact with calcified plaques, greatly reducing frictional resistance, making the balloon pass through the blood vessels of severely calcified lesions more smoothly, and also eliminating the risk of the catheter getting stuck when withdrawing, ensuring the smooth progress of the operation.

[0032] Meanwhile, the elastic restraint component is built-in in this application, with the outer wall of the balloon contacting the blood vessel, avoiding scratching of the intima by external restraint elements. Furthermore, the elastic restraint component allows the balloon to apply pressure evenly, preventing excessive local pressure, better protecting the integrity of the intima, and reducing restenosis.

[0033] Furthermore, when the balloon inflates, it stretches the elastic restraint component to expand; and when the balloon deflates, the elastic restraint component automatically retracts to its initial state due to its own elasticity. This characteristic gives the elastic restraint component multiple functions: first, it ensures that the elastic restraint component always remains synchronized with the balloon's expansion and contraction; second, during balloon inflation, the elastic restraint component effectively prevents the balloon from over-inflating; and third, when the balloon needs to deflate, the elastic restraint component helps the balloon quickly return to its initial state. Attached Figure Description

[0034] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0035] Figure 1 This is a schematic diagram of the internal constraint-type balloon dilation catheter structure in a specific embodiment of the present invention. Figure 1 ;

[0036] Figure 2This is a schematic diagram of the internal constraint-type balloon dilation catheter structure in a specific embodiment of the present invention. Figure 2 ;

[0037] Figure 3 for Figure 1 , 2 A schematic diagram of the structure of the elastic constraint assembly consisting of two oblique constraint members;

[0038] Figure 4 for Figure 1 , 2 Side view of the central balloon;

[0039] Figure 5 for Figure 1 , 2 Schematic diagram of the elastic constraint component structure Figure 1 ;

[0040] Figure 6 for Figure 1 , 2 Schematic diagram of the elastic constraint component structure Figure 2 ;

[0041] The components include: catheter assembly 1, first inlet 10, second inlet 11; inner tube 2, tip 20; balloon 3; elastic restraint assembly 4, first direction restraint 41, bending section 411, second direction restraint 42, bending unit 421, vertical line portion 421-1; occipital portion 5; and groove 6. Detailed Implementation

[0042] The technical solutions of the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this utility model, and not all embodiments. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of this utility model.

[0043] In this article, the term "distal" refers to the end of the internally restrained balloon dilatation catheter inserted into the blood vessel, or the end closest to the treatment site. "Proximal" refers to the end of the internally restrained balloon dilatation catheter closest to the operator, or the end connected to the operating device.

[0044] The following is in conjunction with the appendix Figure 1 To be continued Figure 6 The present invention will be described in detail with reference to specific embodiments:

[0045] like Figure 1-6 As shown, this utility model provides an internally constrained balloon dilation catheter, which includes:

[0046] Catheter assembly 1, wherein the catheter assembly 1 is provided with a first inlet 10 and a second inlet 11;

[0047] Inner tube 2, which is coaxially inserted inside the catheter assembly 1, extends distally to the outside of the distal end of the catheter assembly 1 and forms a tip 20, and the proximal end of the inner tube 2 communicates with the first inlet 10 to form a guidewire lumen for inserting a guidewire.

[0048] Balloon 3 is connected to the distal end of the catheter assembly 1. The inner lumen of the balloon 3 is connected to the second inlet 11 to form an inflation chamber, that is, the second inlet 11 is connected to the inner lumen of the balloon 3 for filling or releasing a medium.

[0049] The elastic restraint component 4 has a compressed state and an inflated state. In the inflated state, the elastic restraint component 4 is a tubular structure, and the balloon 3 is surrounded by the elastic restraint component 4. At this time, the elastic restraint component 4 is placed in the inner cavity of the balloon 3 and is fixedly connected to the inner wall of the balloon 3. When the balloon 3 inflates, the elastic restraint component 4 plays a supporting and shaping role, making the balloon 3 form a structure similar to the occipital region 5 and the groove. The occipital region 5 applies pressure to create a micro-layer, achieving effective expansion, while the groove 6 buffers stress and prevents the layer from expanding.

[0050] Specifically, in this invention, there are no specific limitations on how the elastic restraint component 4 is fixed in the inner cavity of the balloon 3; welding, bonding, etc., are all acceptable methods. For example, the balloon 3 is first expanded, and then the elastic restraint component 4 is connected to form a preset shape. The elastic restraint component 4 is compressed on the outside of the small balloon of another small balloon dilation catheter, and adhesive is applied to the outer wall of the elastic restraint component 4. Next, the small balloon dilation catheter is advanced to send the small balloon and the elastic restraint component 4 into the balloon 3 together, expanding the small balloon so that the elastic restraint component 4 contacts the inner wall of the balloon 3 and is bonded to the inner wall of the balloon 3. After bonding is completed, the small balloon is contracted, and the connection between the elastic restraint component 4 and the balloon 3 is completed.

[0051] When in use, when the balloon 3 is expanded, the balloon 3 will expand due to inflation, which will drive the elastic restraint component 4 to expand. After it is inflated to a certain outer diameter, the elastic restraint component 4 can no longer expand, but the balloon 3 can continue to expand. The local structure of the balloon 3 will protrude from the restraint of the elastic restraint component 4 to form the occipital region 5, and the part of the balloon 3 restrained by the elastic restraint component 4 will form a groove 6, so that the outer surface of the balloon 3 presents a groove and an occipital region.

[0052] In this invention, the built-in constraint balloon dilation catheter places the elastic constraint component 4 inside the balloon 3, avoiding direct contact with calcified plaques, greatly reducing frictional resistance, making the balloon 3 pass through the blood vessels of severely calcified lesions more smoothly, and eliminating the risk of the catheter getting stuck when withdrawing, thus ensuring the smooth progress of the operation.

[0053] Meanwhile, in this application, the elastic restraint component 4 is built-in, and the outer wall of the balloon 3 contacts the blood vessel, avoiding scratching of the intima by external restraint elements. Furthermore, the elastic restraint component 4 allows the balloon 3 to apply pressure evenly, preventing excessive local pressure, better protecting the integrity of the intima, and reducing restenosis.

[0054] Furthermore, when balloon 3 inflates, it stretches the elastic restraint component 4 to expand; and when balloon 3 contracts, the elastic restraint component 4 can automatically retract to its initial state (the initial state of the elastic restraint component 4 is a compressed state) due to its own elasticity. This characteristic gives the elastic restraint component 4 multiple functions: first, it ensures that the elastic restraint component 4 always remains synchronized with the expansion and contraction of balloon 3; second, during the inflation of balloon 3, the elastic restraint component 4 can effectively prevent balloon 3 from over-inflating; and third, when balloon 3 needs to retract, the elastic restraint component 4 helps balloon 3 quickly return to its initial state.

[0055] In one embodiment of this application, the outer diameter of the distal end of the balloon 3 is equal to the outer diameter of the proximal end of the balloon 3, and the outer diameters of the two ends of the balloon 3 are equal after inflation.

[0056] In one embodiment of this application, the outer diameter of balloon 3 gradually decreases from proximal to distal. Since the inner diameter of a blood vessel is not fixed, along the direction of movement of the dilating catheter within the vessel, the inner diameter of the distal end of the vessel is smaller than that of the proximal end. By gradually decreasing the outer diameter of balloon 3 from proximal to distal, it can better conform to the shape of the blood vessel and adapt to lower limb blood vessels, including but not limited to the iliac artery, femoral artery, popliteal artery, infrageninal artery, and tibial artery, thereby enhancing the therapeutic effect. Of course, the outer diameter of balloon 3 can also gradually increase from proximal to distal.

[0057] Furthermore, in some specific embodiments, when the outer diameter of the distal end of the balloon 3 is equal to the outer diameter of the proximal end of the balloon 3, the elastic constraint component 4 as a whole has the same preset deformation capability.

[0058] As the outer diameter of the balloon 3 gradually increases or decreases from the distal end to the proximal end, the pre-deformation capability of the elastic constraint component 4 gradually increases or decreases synchronously from the distal end to the proximal end along the axial direction of the catheter assembly 1, so as to adapt to the needs of different expansion and contraction amounts at different positions.

[0059] This design directly adapts to the deformation characteristics of the balloon 3 during inflation. When the outer diameter of the balloon 3 differs at different locations (gradually increasing or decreasing from the distal to the proximal end), the pre-set deformation capacity of each segment of the elastic restraint component 4 can change synchronously. This allows the elastic restraint component 4 to precisely fit the expansion and contraction requirements of the balloon 3 at different locations, ensuring that the elastic restraint component 4 always fits tightly with the balloon 3 during inflation, avoiding localized loosening or excessive tightness due to mismatch.

[0060] When the distal and proximal outer diameters of balloon 3 are equal, the elastic constraint component 4 as a whole has the same pre-deformation capacity, ensuring that the balloon 3 is subjected to uniform force in all parts when it is inflated. This helps balloon 3 to better perform its function, such as in interventional treatment, enabling balloon 3 to expand blood vessels or other cavities more stably and achieve a more ideal treatment effect.

[0061] Furthermore, in some specific embodiments, the elastic constraint component 4 includes multiple parallel first-direction constraint members 41 and multiple parallel second-direction constraint members 42. The first-direction constraint members 41 and the second-direction constraint members 42 are interwoven or connected at a preset angle to form multiple mesh openings. When the balloon 3 is inflated, the outer surface of the balloon 3 is constrained by the mesh openings, and a portion of the balloon 3 protrudes outward from the mesh openings to form a posterior portion 5. When the balloon 3 expands, the shape of the mesh openings can be one or more of rectangles, rhombuses, parallelograms, and regular hexagons, which can be designed and selected by those skilled in the art based on actual conditions.

[0062] In one embodiment of this application, the shape and size of the mesh determine the height of the pillow portion 5. For example, when the mesh shape is the same, the larger the mesh size, the higher the pillow portion 5 protrudes from the elastic restraint component 4. In this embodiment, when the balloon 3 expands, the height of the pillow portion 5 is 0.01mm-1mm.

[0063] Specifically, in Scheme 1, the first directional constraint member 41 is an axial constraint member, arranged along the axial direction of the catheter assembly 1, and multiple first directional constraint members 41 are arranged at equal intervals along the circumference of the balloon 3; the second directional constraint member 42 is a radial constraint member, arranged at equal intervals along the axial direction of the balloon 3; correspondingly, after the balloon 3 expands, a portion of the balloon 3 protrudes outward from the mesh to form a pillow portion 5, which is rectangular in shape. Preferably, the number of axial constraint members is three, spaced at 120° angles. Of course, the number of axial constraint members can also be four, five, six, etc., and this utility model does not impose a specific limitation.

[0064] In Scheme 2, the first directional constraint member 41 is an axial constraint member, that is, it is arranged along the axial direction of the catheter assembly 2, and multiple first directional constraint members 41 are arranged at equal intervals along the circumference of the balloon 3; the second directional constraint member 42 is an oblique constraint member, which is arranged at equal intervals along the axial direction of the balloon 3; correspondingly, after the balloon 3 expands, a part of the balloon 3 protrudes outward from the mesh to form a occipital portion 5, and the shape of the occipital portion 5 is a parallelogram occipital portion.

[0065] In Option 3, such as Figure 3As shown, the first directional constraint member 41 is an oblique constraint member, which is arranged at equal intervals along the axial direction of the balloon 3; the second directional constraint member 42 is an oblique constraint member, which is arranged at equal intervals along the axial direction of the balloon 3, and the arrangement directions of the two intersect; correspondingly, after the balloon 3 expands, a part of the balloon 3 protrudes outward from the mesh to form a pillow 5, and the shape of the pillow 5 is a rhomboid pillow.

[0066] Specifically, the first directional constraint member 41 is composed of multiple interconnected and spaced-apart bent segments 411, such as... Figure 6 As shown.

[0067] When the outer diameter of the distal end of the balloon 3 is equal to the outer diameter of the proximal end of the balloon 3, the number or bending curvature of each segment of the first directional constraint member 41 is the same.

[0068] As the outer diameter of the balloon 3 gradually increases or decreases from the distal end to the proximal end, the number or bending arc of the first directional constraint member 41 bending segment 411 from the distal end to the proximal end gradually increases or decreases, so that the pre-set deformation capacity of the first directional constraint member 41 achieves a gradual change effect, meets the needs of different positions for expansion and contraction, and adapts to the deformation characteristics of the balloon 3 during expansion.

[0069] More specifically, such as Figure 5 , 6 As shown, the second directional constraint 42 is divided into multiple bending units 421, which are connected end-to-end to form a ring-shaped second directional constraint 42. Each bending unit 421 is fixedly connected to the first directional constraint 41 to prevent the first directional constraint 41 from slipping on the balloon 3 and to prevent the first directional constraint 41 from becoming entangled. The bending unit 421 can stretch or contract the bending portion to achieve the stretching or contraction of the second directional constraint 42. It should be noted that the second directional constraint 42 can be a split structure, i.e., formed by sequentially bonding or welding multiple bending units 421 end-to-end, or it can be designed as a one-piece structure for ease of manufacturing.

[0070] The bending unit 421 can be made of different types, such as springs, sheet springs, and spiral springs. By selecting different materials, it can be adapted to various application scenarios. When dealing with high-pressure calcified lesions, a spring is selected as the bending unit 421. When the high-pressure balloon is inflated, the spring absorbs energy through linear elastic deformation, thereby evenly distributing the stress and effectively avoiding local overload. This high elastic deformation matches the high-pressure inflation of the balloon, which can evenly disperse the reaction force generated by the calcified plaque, significantly reducing the risk of vascular rupture.

[0071] In scenarios requiring precise limiting of balloon expansion, such as for fragile blood vessels, a spring clip should be used as the bending unit 421. In such cases where precise limitation of balloon expansion is necessary, an expansion threshold can be set based on the stiffness of the spring clip to prevent over-inflation of the balloon. The spring clip, relying on a rigid threshold, limits excessive balloon expansion, thus protecting the fragile diseased blood vessel while ensuring that the narrowed area is adequately dilated.

[0072] For interventions involving tortuous vessels, such as neurointerventions or procedures within tortuous vessels, the hairspring is a suitable bending unit 421 choice. The hairspring's multi-directional bending characteristics allow it to adapt to complex anatomical structures while maintaining a low outer diameter and high throughput. Its ultra-flexible and miniaturized design reduces frictional resistance when navigating tortuous sections, effectively preventing vascular spasm or perforation.

[0073] Correspondingly, when the outer diameter of the distal end of the balloon 3 is equal to the outer diameter of the proximal end of the balloon 3, the number or bending radius of the bending units 421 of the second directional constraint member 42 are the same, so as to adapt to the deformation characteristics of the balloon 3 during expansion.

[0074] As the outer diameter of the balloon 3 gradually increases or decreases from the distal end to the proximal end, the number or bending radius of the bending unit 421 in the second directional constraint member 42 gradually increases or decreases from the distal end to the proximal end, so that the preset deformation capacity of the second directional constraint member 42 achieves a gradual change effect, meets the needs of different positions for expansion and contraction, and adapts to the deformation characteristics of the balloon 3 during expansion.

[0075] In this embodiment, the bending unit 421 is a horizontally arranged "Ω"-shaped structure, wherein the vertical portion 421-1 is fixedly connected to the first directional constraint member 41. When the balloon 3 inflates, the apex of the "Ω"-shaped structure expands outward, releasing radial expansion space; when it contracts, it elastically returns to its original shape, synchronizing with the expansion / contraction dynamics of the balloon 3 and reducing hysteresis effects. In addition, the symmetry and arc-shaped contour of the "Ω"-shaped structure can buffer repeated deformation energy, and the end-to-end connection between units forms a continuous support ring, further dispersing alternating stress and improving the durability of the constraint member.

[0076] When treating stenotic lesions, a guidewire is first inserted into the target location of the blood vessel. Then, the in-situ constriction balloon dilation catheter of this application is inserted through the guidewire, which extends from the tip 20 to the first inlet 10, and the balloon 3 is inserted into the lesion site. Subsequently, a filling medium is introduced through the second inlet 11 to inflate the balloon 3. When the balloon 3 inflates to the nominal pressure, it protrudes from the mesh of the elastic constriction component 4 to form a occipital portion 5. The elastic constriction component 4 is located within a groove 6 between two adjacent occipital portions 5. During action on the blood vessel, the occipital portion 5 generates stress, while the adjacent groove releases stress, preventing disordered tearing of the vascular intima. Due to the material of the elastic constriction component 4 and its connection method with the balloon 3, the risk of the elastic constriction component 4 becoming entangled with calcified plaques or stent structures is reduced.

[0077] The present invention has been further described above with reference to specific embodiments. However, it should be understood that the specific description herein should not be construed as limiting the substance and scope of the present invention. Various modifications made by those skilled in the art to the above embodiments after reading this specification are all within the scope of protection of the present invention.

Claims

1. A built-in restraint balloon dilation catheter, characterized in that: It includes: The catheter assembly has a first inlet and a second inlet; The inner tube is coaxially inserted inside the catheter assembly. The distal end of the inner tube extends to the outside of the distal end of the catheter assembly and forms a tip. The proximal end of the inner tube communicates with the first inlet to form a guidewire lumen. A balloon, the balloon being connected to the distal end of the catheter assembly, the inner lumen of the balloon communicating with the second inlet to form an inflation chamber; An elastic restraint assembly has a compressed state and an inflated state. In the inflated state, the elastic restraint assembly is a tubular structure. The balloon surrounds the elastic restraint assembly, and the elastic restraint assembly is fixedly connected to the inner wall of the balloon.

2. The built-in restraint balloon dilation catheter according to claim 1, characterized in that: When the outer diameter of the distal end of the balloon is equal to the outer diameter of the proximal end of the balloon, the elastic constraint assembly as a whole has the same preset deformation capacity. As the outer diameter of the balloon gradually increases or decreases from the distal end to the proximal end, the pre-deformation capability of the elastic constraint component gradually increases or decreases synchronously from the distal end to the proximal end along the axial direction of the catheter assembly.

3. The built-in restraint balloon dilation catheter according to claim 1, characterized in that: The elastic constraint component includes multiple parallel first-direction constraint members and multiple parallel second-direction constraint members. The first-direction constraint members and the second-direction constraint members are interwoven or connected at a preset angle to form multiple mesh holes. When the balloon is inflated, the outer surface of the balloon is restricted by the mesh holes, and a part of the balloon protrudes outward from the mesh holes to form a occipital region.

4. The built-in restraint balloon dilation catheter according to claim 3, characterized in that: The first directional constraint is disposed along the axial direction of the conduit assembly.

5. The built-in restraint balloon dilation catheter according to claim 3, characterized in that: When the balloon expands, the shape of the mesh is one or more of the following: rectangular, rhomboid, parallelogram, and regular hexagon.

6. The built-in restraint balloon dilation catheter according to claim 3, characterized in that: When the balloon is inflated, the height of the occipital region is 0.01mm-1mm.

7. The built-in restraint balloon dilation catheter according to any one of claims 3-6, characterized in that: The first directional constraint member is composed of multiple interconnected and spaced-apart bent segments; When the outer diameter of the distal end of the balloon is equal to the outer diameter of the proximal end of the balloon, the number of bending segments or the bending radius in each segment of the first directional constraint member are the same. As the outer diameter of the balloon gradually increases or decreases from the distal end to the proximal end, the number of bending segments or the bending arc of the first directional constraint member from the distal end to the proximal end gradually increases or decreases synchronously.

8. The built-in restraint balloon dilation catheter according to claim 7, characterized in that: The second directional constraint is divided into multiple bending units, and the first and last ends of the multiple bending units are connected in sequence to form a ring-shaped second directional constraint. The bending units are all fixedly connected to the first directional constraint member.

9. The built-in restraint balloon dilation catheter according to claim 8, characterized in that: When the outer diameter of the distal end of the balloon is equal to the outer diameter of the proximal end of the balloon, the number of bending units or the bending radius of the entire second directional constraint member are the same. As the outer diameter of the balloon gradually increases or decreases from the distal end to the proximal end, the number of bending units or the bending radius of the second directional constraint member gradually increases or decreases synchronously from the distal end to the proximal end.

10. The built-in restraint balloon dilation catheter according to claim 8, characterized in that: The bending unit is a horizontally arranged "Ω" shaped structure, wherein the vertical part is fixedly connected to the first direction constraint member.

Images