Balloon dilatation catheter, balloon pre-dilatation system and balloon dilatation method

Abstract

The invention relates to a balloon dilatation catheter, a balloon pre-dilatation system and a balloon dilatation method. The balloon dilatation catheter comprises a catheter body structure and a balloon dilatation catheter, wherein the catheter body structure comprises a fluid conveying channel; the first balloon is fixed on the tube body structure and is communicated with the fluid conveying channel; the second balloon is fixed to the tube body structure, a gap is formed between the second balloon and the first balloon in the far and near end direction, and the second balloon communicates with the fluid conveying channel; the third balloon is fixed to the tube body structure, and the third balloon wraps the first balloon and the second balloon. The balloon dilatation catheter can be effectively clamped on a valve ring, and dilatation can be achieved.

Description

Technical Field

[0001] This application relates to the field of medical device technology, and in particular to balloon dilation catheters, balloon pre-dilation systems, and balloon dilation methods. Background Technology

[0002] In transcatheter aortic valve replacement (TAVR), pre-dilation of the aortic valve calcification stenosis lesion is a crucial step that determines the success of the procedure.

[0003] Balloons are commonly used for dilation, but the results are often less than ideal. While traditional straight-tube balloons can evenly dilate the valve leaflets, when inflated, they are prone to slipping forward into the ventricle or backward into the aorta due to blood flow impact and transvalvular pressure gradients. This necessitates repeated repositioning, prolonging the time the balloon obstructs the valve orifice, extending the procedure time, and increasing the risk of complications. Balloons are not adapted to the natural anatomical curvature of blood vessels, potentially leading to localized stress concentration. Furthermore, pre-shaped balloons have a fixed rated diameter, making it difficult to accommodate individual differences in vessel diameter. Too small a diameter results in incomplete blood flow obstruction, while too large a diameter can cause vascular tearing. They are particularly unsuitable for patients with calcified lesions or tortuous blood vessels.

[0004] To improve balloon usage, some new balloons feature a narrowed lumbar section with a diameter smaller than that of the two ends. However, this pre-fabricated shape cannot be well adapted to different needs. To ensure positioning effectiveness, the balloon diameter needs to be significantly larger than the lumbar diameter. However, if the lumbar diameter is too small, it cannot open the calcified leaflets, failing to achieve the desired dilation effect. Increasing the lumbar diameter also proportionally increases the diameters of the two ends, potentially causing damage to the ventricular wall and leading to complications. Summary of the Invention

[0005] Therefore, it is necessary to provide a balloon dilation catheter, a balloon pre-dilation system, and a balloon dilation method to address at least one of the above-mentioned problems.

[0006] In a first aspect, this application provides a balloon dilation catheter, which includes: a tube body structure including a fluid delivery channel; a first balloon fixed to the tube body structure and connected to the fluid delivery channel; a second balloon fixed to the tube body structure and spaced from the first balloon in a proximal-distal direction, the second balloon being connected to the fluid delivery channel; and a third balloon fixed to the tube body structure, the third balloon enclosing the first balloon and the second balloon.

[0007] By placing the first and second balloons inside the third balloon as inner balloons, and filling the first and second balloons with fluid to expand them, the first and second balloons are supported by the expansion of the spaced-apart first and second balloons, forming a third balloon with a dog bone-shaped waist structure.

[0008] The spacing between the first and second balloons allows the third balloon to be shaped like a dog's bone or a dumbbell. The portion of the third balloon located between the first and second balloons is expanded to resemble a hyperboloid, ensuring that the balloon dilation catheter can be effectively secured within the valve annulus and preventing catheter movement. Furthermore, the dilation of the first and second balloons allows for variations in the dog's bone shape, making it suitable for vessels of different diameters and offering greater flexibility.

[0009] In some embodiments, the first fluid delivery channel includes a first cavity and a second cavity, the first cavity being connected to a first balloon and the second cavity being connected to a second balloon.

[0010] This configuration allows for separate control of the first and second balloons, which helps to create a more adaptable dog bone shape.

[0011] In some embodiments, the burst pressure of the third balloon is greater than the burst pressure of at least one of the first and second balloons.

[0012] This setup allows the first and / or second balloons to be inflated to fill the third balloon with fluid. When the third balloon acts as the external balloon, it continues to expand in one step and two stages through the first and / or second cavities. This results in good stress release, accurate positioning, and minimal damage to blood vessels. It is also simple to operate, reduces pre-dilation time, and lowers the risk of pre-dilation during surgery.

[0013] The two inner balloons can be the same or different; generally they are the same, but they can be different in special cases, depending on the actual situation. For example, in special circumstances, such as when the diameter of the ventricle differs greatly from that of the aorta, the two inner balloons can be different; or the two inner balloons can be the same, but with different filling velocities, to prevent the balloons from shifting due to differences in the cavity space, which could lead to inaccurate positioning.

[0014] In some embodiments, the nominal shapes of the first balloon and the second balloon are both circular or elliptical; when both the first balloon and the second balloon are inflated, the portion of the third balloon located between the first balloon and the second balloon can be pulled up.

[0015] With this configuration, the first and second balloons can expand uniformly; the portion of the third balloon located between the first and second balloons is supported in a shape that is close to a hyperboloid, preventing movement and ensuring uniform expansion.

[0016] In some implementations, the first, second, and third balloons are either compliant or non-compliant balloons.

[0017] In some implementations, the first and second balloons are compliant balloons, and the third balloon is a non-compliant balloon.

[0018] With this configuration, the non-compliant balloon provides strong support and high pressure, effectively forming the desired outer contour.

[0019] In some embodiments, the materials of the first and second balloons respectively include at least one selected from polyethylene, polyethylene terephthalate, polyamide, and polyether block polyamide. Exemplarily, the material of the third balloon includes at least one selected from polyethylene, polyethylene terephthalate, polyamide, and polyether block polyamide.

[0020] With this configuration, the third balloon achieves good non-compliance, high puncture resistance, and a certain pressure resistance.

[0021] In some embodiments, the fluid delivery channel includes a first cavity and a second cavity, the first cavity being connected to a first balloon and the second cavity being connected to a second balloon.

[0022] This configuration allows for separate control of the first and second balloons, which helps to create a more adaptable dog bone shape.

[0023] In some embodiments, the tubular structure further includes a third cavity that communicates with a third balloon.

[0024] This design allows for the direct injection of filling fluid into the third balloon through the third cavity, causing the third balloon to expand.

[0025] Optionally, when there is no third cavity connecting to the third balloon, the burst pressure of at least one of the first and second balloons is less than the burst pressure of the third balloon, so that the outer balloon can be inflated after the inner balloon ruptures. When the third balloon is connected to the third cavity, the burst pressure of the third balloon can be greater than, equal to, or less than the burst pressure of either the first or second balloon, because the inner balloon can be inflated without bursting, and the outer balloon can be inflated solely through the third cavity.

[0026] In some implementations, the first cavity, the second cavity, and the third cavity may be configured in the same or different fluid delivery channels.

[0027] In some embodiments, the first cavity and the second cavity are disposed in the first fluid delivery channel, and the third cavity is disposed in the second fluid delivery channel.

[0028] In some embodiments, the burst pressure of the first balloon and the burst pressure of the second balloon are both less than 2 atm; the burst pressure of the third balloon is greater than 3 atm.

[0029] This design ensures that the first and second balloons can be inflated and burst, while preventing the third balloon from being damaged when the inner balloon bursts.

[0030] For example, the burst pressure range of the first balloon and the burst pressure range of the second balloon are both 0.5 atm to 2 atm; the burst pressure of the third balloon is greater than 4 atm.

[0031] This configuration ensures that the first and second balloons have good support capabilities and can be reliably inflated when needed; the third balloon itself has strong support capabilities.

[0032] In some embodiments, the wall thickness of the first balloon and the wall thickness of the second balloon are both less than the wall thickness of the third balloon.

[0033] For example, the wall thickness of both the first balloon and the second balloon is less than 0.05 mm.

[0034] In some embodiments, the first and / or second balloons have weak areas. A weak area refers to a region whose mechanical properties are weaker than the rest of the balloon. During inflation, the weak area may rupture first. The weak area can be formed by reducing the wall thickness on the surface of the balloon. By setting the weak area, the first and / or second balloons can achieve complete or partial bursting.

[0035] In some embodiments, the critical pressure at which the first and / or second balloons expand to a critical state is less than the preset pressure for the rated expansion of the third balloon (i.e., the nominal pressure at which the third balloon is fully expanded). When the first and / or second balloons expand to the critical state and burst, the third balloon has not yet expanded to the preset pressure for rated expansion. This avoids the danger of the third balloon bursting along with the first and / or second balloons, thus improving the safety of the balloon dilation catheter.

[0036] In some embodiments, the volume of the first and / or second balloon at its critical pressure is less than the volume of the third balloon at its preset pressure. It is not necessary to limit the critical pressure of the first and / or second balloons to be less than the preset pressure for the rated expansion of the third balloon. Because there is a volume difference between the inner and outer balloons when the first and / or second balloons burst, the pressure inside the first and / or second balloons will drop instantaneously due to the incompressibility of liquids. Therefore, setting the critical pressure of the inner balloon higher than the preset pressure for the rated expansion of the third balloon can also achieve safe use. This setting makes it easier to achieve the design target parameters and ensure the effectiveness of the balloon dilation catheter.

[0037] Secondly, this application provides a balloon pre-dilation system, including: the aforementioned balloon dilation catheter; and an inflation device connected to the tube body structure.

[0038] The balloon pre-dilation system of this application can be used for pre-dilation of cardiovascular diseases such as aortic valve calcification and stenosis.

[0039] Thirdly, this application provides a method for using a balloon dilation catheter, wherein the balloon dilation catheter is the aforementioned balloon dilation catheter or the balloon dilation catheter of the aforementioned balloon pre-dilation system. The method includes: inflating both a first balloon and a second balloon with filling fluid, causing the first and second balloons to dilate to support a third balloon.

[0040] In some embodiments, the method further includes: inflating the third balloon with filling fluid to inflate the third balloon.

[0041] Exemplarily, the method further includes: inflating at least one of a first balloon and a second balloon, and inflating a third balloon with filling fluid through a cavity connected to the first balloon and / or the second balloon. Exemplarily, filling fluid is inflated through a cavity connected to the third balloon.

[0042] The inflation of the inner balloon allows the filling fluid to directly enter the third balloon for expansion, enabling a one-step inflation operation.

[0043] The method for balloon dilation catheters described in this application is simple to operate and easy to execute; it can achieve a two-stage expansion change mode. Attached Figure Description

[0044] Figure 1 A schematic structural diagram of a balloon dilation catheter according to one or more embodiments;

[0045] Figure 2 A schematic cross-sectional view of a balloon dilation catheter according to one or more embodiments;

[0046] Figure 3 A schematic cross-sectional view of a balloon dilation catheter following the rupture of a first balloon according to one or more embodiments;

[0047] Figure 4 A schematic cross-sectional view of a balloon dilation catheter according to one or more embodiments;

[0048] Figure 5 A schematic diagram of the structure of a balloon dilation catheter in the first fluid filling stage according to one or more embodiments;

[0049] Figure 6 A schematic diagram of the structure of a balloon dilation catheter in the second fluid filling stage according to one or more embodiments;

[0050] Figure 7 A schematic structural block diagram of a balloon pre-dilation system according to one or more embodiments;

[0051] Figure 8 This is a schematic flowchart of a method for a balloon dilation catheter according to one or more embodiments.

[0052] Explanation of reference numerals in the attached drawings: 1. Tube structure; 110. Fluid transport channel; 111. First cavity; 112. Second cavity; 113. Third cavity; 120. Guide wire channel; 11. Outer tube; 12. Inner tube;

[0053] 21. First balloon; 22. Second balloon; 23. Third balloon; 231. First connecting segment; 232. Middle segment; 233. Second connecting segment;

[0054] 1000, Balloon dilation catheter; 2000, Balloon pre-dilation system; 2100, Inflation device. Detailed Implementation

[0055] To make the above-mentioned objectives, features, and advantages of this application more apparent and understandable, the specific embodiments of this application are described in detail below with reference to the accompanying drawings. Many specific details are set forth in the following description to provide a thorough understanding of this application. However, this application can be implemented in many other ways different from those described herein, and those skilled in the art can make similar modifications without departing from the spirit of this application. Therefore, this application is not limited to the specific embodiments disclosed below.

[0056] In the description of this application, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc., indicating the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application.

[0057] In this application, unless otherwise expressly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature is in indirect contact with the second feature through an intermediate medium. Furthermore, "above," "on top of," and "over" the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0058] Furthermore, the terms "first," "second," and "third," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. For example, a first balloon may also be referred to as a second balloon, and a second balloon may also be referred to as a first balloon. In the description of this application, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0059] In this application, unless otherwise expressly specified and limited, the terms "connected," "linked," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; a flexible connection or a rigid connection along at least one direction; a mechanical connection or an electrical connection; a direct connection or an indirect connection through an intermediate medium, or a direct connection with an intermediate medium present; and they can also refer to the internal communication of two components or the interaction between two components, unless otherwise expressly limited. The terms "installed," "set," "fixed," etc., can be broadly understood as connection. For those skilled in the art, the specific meaning of the above terms in this application can be understood according to the specific circumstances.

[0060] As used in this application, the terms "layer" and "region" refer to a material portion comprising a defined area and having a defined thickness. A layer can extend horizontally, vertically, and / or along a conical surface. A layer can be a region of uniform or non-uniform continuous structure, and its thickness perpendicular to the direction of extension may not exceed the thickness of the continuous structure. A layer can comprise multiple layers, which can be stacked layers or discretely extending layers. The shapes of the various regions and layers in the accompanying drawings, as well as their relative sizes and positional relationships, are merely illustrative and may deviate from actual dimensions due to manufacturing tolerances or technical limitations, and the design can be adjusted according to actual needs.

[0061] It should be noted that, in this application, the terms "distal" and "proximal" are used with the operator as the reference point. The end closer to the operator is called the proximal end or proximal portion, and the end farther from the operator is called the distal end or distal portion. The side facing the operator is called the proximal side or proximal side, and the side away from the operator is called the distal side or distal side. In addition, "distal direction" and "proximal direction" represent two directions; the proximal-distal direction is parallel to the distal direction and the proximal direction, and the proximal-distal direction does not specifically refer to forward or reverse directions.

[0062] A compliant balloon is defined as a balloon whose diameter at the rated burst pressure is greater than 30% of its nominal diameter, while a non-compliant balloon is defined as a balloon whose diameter at the rated burst pressure is no greater than 15% of its nominal diameter. When a balloon is filled with filling fluid at its nominal pressure, it will expand to a certain size, typically with a roughly circular cross-section. The outer diameter of the balloon at this point is its nominal diameter. Continuing to fill the balloon with filling fluid at its nominal diameter causes further expansion, eventually leading to rupture. The pressure inside the balloon at the moment of rupture is the burst pressure.

[0063] refer to Figure 1 , Figure 1 A balloon dilation catheter according to an embodiment of this application is illustrated. In an exemplary embodiment, the balloon dilation catheter 1000 includes a tube body structure 1 and a plurality of balloons. The tube body structure 1 may extend in a proximal-distal direction, for example parallel to... Figure 1 The X-axis direction. The distal end of the tube structure 1 can be a conical head, a round head, or a blunt head. The balloon is fitted onto the tube structure 1, and the tube structure 1 passes through the balloon. Along the proximal-distal direction, both ends of the balloon are sealed and connected to the tube structure.

[0064] These balloons include an inner balloon and an outer balloon that surrounds the inner balloon. The inner balloon may include a first balloon 21 and a second balloon 22, and the outer balloon may be a third balloon 23. In one example of this application, the balloon dilation catheter 1000 includes two balloon layers.

[0065] Combination Figure 2 As shown, Figure 2 The illustration shows a balloon dilation catheter 1000 in which the inner balloon supports the outer balloon in an embodiment of this application. In some embodiments, the tube body structure 1 has a fluid delivery channel 110 and may also have a guidewire channel 120 isolated from the fluid delivery channel 110.

[0066] refer to Figure 2 For example, the tube structure 1 may include an outer tube 11 and an inner tube 12, the inner tube 12 having a guide wire channel 120. The outer tube 11 is sleeved on the inner tube 12, and a fluid transport channel 110 may be formed between the outer tube 11 and the inner tube 12.

[0067] refer to Figure 1 The first balloon 21 is fixed to the tubular structure 1. The distance between the two fixing points of the proximal and distal ends of the first balloon 21 on the tubular structure 1 can be approximately equal to the natural distance between the two ends of the first balloon 21 in its uninflated state, or it can be slightly larger or smaller. The uninflated state refers to the balloon being in its naturally relaxed state when it is not filled with any filling fluid (liquid or gas). The first balloon 21 is connected to the fluid delivery channel 110. Optionally, the outlet of the fluid delivery channel 110 corresponding to the first balloon 21 can be approximately located at the center of the first balloon 21.

[0068] The second balloon 22 is fixed to the tubular structure 1. The distance between the two fixing points of the proximal and distal ends of the second balloon 22 on the tubular structure 1 can be approximately equal to the natural distance between the two ends of the second balloon 22 when it is in an uninflated state. The second balloon 22 is connected to the fluid delivery channel 110. Optionally, the outlet of the fluid delivery channel 110 corresponding to the second balloon 22 can be approximately located at the center of the second balloon 22.

[0069] refer to Figure 1 The fixed distance between the distal and proximal ends of the third balloon 23 is L1, and the distance between the proximal end of the first balloon 21 and the distal end of the second balloon 22 is L2. L2 can be 20% to 50% of L1, such as 30% or 40%. If this distance is too long, it may cause the outer diameter of the two inner balloons to be too small when they are filled. If this distance is too short, it may cause the indentation in the middle of the outer balloon to be indistinct. Neither of these can achieve a good positioning effect.

[0070] The two inner balloons can have the same nominal diameter, which makes manufacturing easier, and they can be interchanged before being fixed in place. The two inner balloons can also have different nominal diameters. When the space used is special, such as when the diameter of the ventricle differs greatly from that of the aorta, a specific first balloon 21 and a second balloon 22 can be designed according to the requirements.

[0071] The nominal diameter ratio of the third balloon 23 to the first balloon 21 or the second balloon 22 is 1.5 to 3.0.

[0072] The second balloon 22 and the first balloon 21 are spaced apart along the proximal-distal direction. The size of the first gap, L2, can be smaller than the span between the proximal and distal ends of either of the two inner balloons. Exemplarily, the second balloon 22 is located proximal to the first balloon 21. The third balloon 23 is fixed to the tube structure 1. The third balloon 23 encloses the first balloon 21 and the second balloon 22. The distal end of the third balloon 23 may have a second gap with the distal end of the first balloon 21, and the proximal end of the third balloon 23 may have a third gap with the proximal end of the second balloon 22. Exemplarily, the first connecting segment 231 and the second connecting segment 233 of the third balloon 23 can both be convex conical in shape.

[0073] The third balloon 23 may include a first connecting segment 231, an intermediate segment 232 and a second connecting segment 233 arranged sequentially along the proximal-distal direction. For example, the first connecting segment 231 is located distal to the intermediate segment 232. Figure 1 and Figure 2 The third balloon 23 may not yet be inflated. Supported by the two inner balloons, the third balloon 23 is under low pressure. Figure 3 , Figure 6 The third balloon 23 in the middle can be in an expanded state.

[0074] The burst pressure of the third balloon 23 is greater than that of at least one of the first balloon 21 and the second balloon 22. When at least one of the first balloon 21 and the second balloon 22 is ruptured, at least one of the first cavity 111 and the second cavity 112 in the fluid delivery channel 110 can be connected to the third balloon 23.

[0075] Figure 1 , Figure 2 and Figure 3 The filling fluid is not shown; it can be a gas or a liquid. A liquid may have better resistance to deformation and be more stable when the inner balloon bursts. Specifically, a contrast agent can be injected to allow instruments to observe the position and status of the balloon dilation catheter 1000.

[0076] The balloon dilation catheter 1000 provided in this application embodiment can be used in transcatheter aortic valve replacement surgery. The balloon dilation catheter 1000 can be passed through the femoral artery along the guidewire until the balloon dilation catheter 1000 reaches the aortic valve annulus.

[0077] The first balloon 21 and the second balloon 22 are inside the third balloon 23. During use, the first balloon 21 and the second balloon 22 can respectively contact and support the corresponding two parts of the third balloon 23. The part of the third balloon 23 located between the first balloon 21 and the second balloon 22 is pulled up. The first balloon 21 and the second balloon 22 are spaced apart so that the outer shape of the third balloon 23 is dog bone-shaped. The supported shape of the third balloon 23 ensures that the balloon dilation catheter 1000 can be effectively locked in the valve annulus, preventing the balloon dilation catheter 1000 from moving.

[0078] During the stage of using the inner balloon to support the outer balloon, the outer balloon is subjected to external force, which allows stress to be released between it and the inner balloon. The third balloon 23 is accurately positioned as the outer balloon, thus minimizing damage to blood vessels.

[0079] refer to Figure 3 The third balloon 23 can be expanded by inflating at least one of the first balloon 21 and the second balloon 22 and continuing to inflate with filling fluid. When the third balloon 23 is used as an external balloon, it can be expanded in one step and two stages through the same cavity as the first balloon 21 and / or the second balloon 22, which can conform to the natural anatomical curvature of the blood vessel and help avoid local stress concentration.

[0080] When the portion of the third balloon 23 located between the first balloon 21 and the second balloon 22 is pulled up, the diameter of this portion in the first stage can be influenced by a combination of factors, adapting to individual differences in vessel diameter and avoiding problems such as vascular tearing due to an excessively large diameter or incomplete blood flow obstruction due to an insufficiently large diameter caused by the use of a fixed-diameter dilation balloon. In the second stage, the third balloon 23 can further dilate the autologous valve in an appropriate posture and relative position to complete pre-dilation. The balloon dilation catheter 1000 can also be used in cases where the patient has calcified lesions or tortuous vessels.

[0081] The balloon dilation catheter 1000 is easy to operate, reduces pre-dilation time, and can reduce the risks of pre-dilation during surgery.

[0082] For example, the tube structure 1 may have a fluid delivery channel 110 and a guide wire channel 120. The fluid delivery channel 110 may include a first cavity 111 and a second cavity 112. The first cavity 111 may be connected to a first balloon 21, and the second cavity 112 may be connected to a second balloon 22, which can control the first balloon 21 and the second balloon 22 respectively, which is beneficial for forming a more adaptable dog bone shape.

[0083] The burst pressure of the first balloon 21 and the burst pressure of the second balloon 22 can be approximately equal; when controlled separately, they can also be different. By expanding the first balloon 21 and the second balloon 22, the diameter of the waist of the dog's bone can be adjusted, which is beneficial for adapting to blood vessels of different diameters.

[0084] refer to Figure 4 The balloon dilation catheter 1000 may further include a third cavity 113 communicating with the third balloon 23. When the first balloon 21 and the second balloon 22 respectively support the first connecting segment 231 and the second connecting segment 233, directly inflating the third balloon 23 with filling fluid through the third cavity 113 can further increase the volume of the intermediate segment 232. By directly inflating the third balloon 23 with filling fluid through the third cavity 113 without bursting the inner balloon, the risk of cardiac complications caused by the impact of the inner balloon bursting can be avoided.

[0085] One of the first balloons 21 and the second balloon 22 used for blasting may have a weak zone, which may be a thinner section or a slit. The weak zone may be positioned along the proximal-distal direction to avoid being directly aligned radially with the third balloon 23.

[0086] refer to Figure 5The nominal shapes of the first balloon 21 and the second balloon 22 can both be circular or elliptical, and both balloons 21 and 22 can expand uniformly. The nominal shapes of the first balloon 21 and the second balloon 22 can be the same or different; for example, the distal balloon can be elliptical. Their nominal diameters can be the same or different; for example, the distal balloon can be larger. Under operating pressure, both balloons can maintain a near-elliptical shape. Figure 5 In the case of a longitudinal section, the nominal shape of the first balloon 21 and the nominal shape of the second balloon 22 can both be circular, and the first balloon 21 and the second balloon 22 can have the same size.

[0087] The third balloon 23 may be spindle-shaped. (Reference) Figure 6 When the third balloon 23 is filled with fluid until it is fully expanded, the middle section 232 is a straight section and can be cylindrical.

[0088] The intermediate segment 232 can be cylindrical when directly filled with fluid, and approximates a hyperboloid when supported by the inner balloon but at lower pressure, thus achieving different shapes for different working stages. The intermediate segment 232 can be used to expand the lesion site, while preventing displacement and ensuring uniform expansion.

[0089] The first balloon 21 and the second balloon 22 are compliant balloons, which can be gradually expanded by filling with fluid. The third balloon 23 is a non-compliant balloon, which provides strong support and high pressure, and can effectively form the desired outer contour. The first balloon 21 and the second balloon 22 can be ruptured while providing effective support.

[0090] The material of the third balloon 23 may include at least one of polyethylene (PE), polyethylene terephthalate (PET), polyamide (PA), and polyether block polyamide (Pebax), such as polyethylene. The third balloon 23 satisfies good noncompliance, high puncture resistance, and certain pressure resistance.

[0091] The materials of the first balloon 21 and the second balloon 22 include at least one of polyethylene, polyethylene terephthalate, polyamide, and polyether block polyamide. The materials of the two balloons can be the same or different; for example, both can be polyamide.

[0092] The tubular structure 1 can be flexible and bendable. The material of the tubular structure 1 includes nylon. The tubular structure 1 and the balloon can be fixed together by adhesive bonding. Optionally, the tubular structure 1 and the third balloon 23 can be fixed together by laser welding.

[0093] The burst pressure of both the first balloon 21 and the second balloon 22 is less than 2 atm. For example, the burst pressure range of both the first balloon 21 and the second balloon 22 is from 0.5 atm to 2 atm, such as 0.6 atm, 0.7 atm, 0.8 atm, or 0.9 atm. This ensures that the first balloon 21 and the second balloon 22 have good support capabilities and can be reliably inflated and deflated when needed.

[0094] The burst pressure of the third balloon 23 is greater than 3 atm. This ensures that the first balloon 21 and the second balloon 22 can be inflated and burst, while preventing the third balloon 23 from being damaged when the inner balloon bursts. For example, the burst pressure of the third balloon 23 is greater than 4 atm; further, it is greater than 6 atm. The third balloon 23 has strong self-supporting capacity.

[0095] For example, the burst pressure of the first balloon 21 is 2 atm, and the nominal pressure of the third balloon 23 is 6 atm.

[0096] The wall thickness of the first balloon 21 and the second balloon 22 are both less than the wall thickness of the third balloon 23, making it easier to achieve the design target parameters. The wall thickness of the first balloon 21 and the second balloon 22 are both less than 0.05 mm, and can be the same or different, to ensure the effectiveness of the balloon dilation catheter 1000.

[0097] In other embodiments, such as when inflating the inner balloon is not required, the wall thickness of the first balloon 21 can be equal to the wall thickness of the third balloon 23, and the wall thickness of the second balloon 22 can also be equal to the wall thickness of the third balloon 23. The wall thickness of the inner balloon can also be greater than the wall thickness of the outer balloon. The wall thickness of the first balloon 21 and the wall thickness of the second balloon 22 can be the same or different. Exemplarily, the inner and outer balloons can be based on the same material or different materials. When the wall thickness of the inner balloon is greater than or equal to the wall thickness of the outer balloon, the inner balloon can still be inflated by selecting the material.

[0098] refer to Figure 7 This application provides a balloon pre-dilation system 2000. The balloon pre-dilation system 2000 may include a balloon dilation catheter 1000 and an inflation device 2100. The balloon dilation catheter 1000 may be the aforementioned balloon dilation catheter 1000. The inflation device 2100 is connected to a fluid delivery channel 110. The balloon pre-dilation system 2000 can be used for pre-dilation of aortic valve calcification stenosis lesions. The balloon pre-dilation system 2000 may also include a controller, etc.

[0099] refer to Figure 2 The outer tube 11 may be connected to the filling device 2100. The process of using the balloon dilation catheter 1000 or the balloon pre-dilation system 2000 may include the following stages.

[0100] During the preoperative preparation phase, each balloon of the balloon dilation catheter 1000 is folded to expel air from the balloons. A standard volume of contrast agent can be prepared into the inflation device 2100, and all components that need to be assembled and connected can be completed.

[0101] During the approach phase, the balloon dilation catheter 1000 passes through the femoral artery along the guidewire until the third balloon 23 reaches the aortic valve annulus.

[0102] During the positioning phase, a certain volume of contrast agent is slowly inflated into the first balloon 21 and the second balloon 22 via the inflation device 2100. The first balloon 21 and the second balloon 22 expand into a dog bone shape, allowing the waist of the third balloon 23 to be secured at the autologous valve annulus. The balloon dilation catheter 1000 remains fixed relative to the valve annulus and will not move up or down.

[0103] During the expansion phase, the developing solution continues to be filled through the filling device 2100. After reaching the burst pressure of the first balloon 21 and the second balloon 22, the first balloon 21 and the second balloon 22 rupture respectively, and the developing solution flows into the third balloon 23. A standard volume of developing solution is pumped into the third balloon 23 to fully inflate the third balloon 23, thereby expanding the autologous valve.

[0104] During the withdrawal phase, after pre-dilation is completed, the fluid in the third balloon 23 is withdrawn, for example, by drawing it to negative pressure, and then the balloon dilation catheter 1000 is withdrawn.

[0105] refer to Figure 3 and Figure 4 Different cavities can be connected to the filling device 2100. The process of use can also include a preoperative preparation stage, an access stage, a positioning stage, an expansion stage, and a withdrawal stage. When filling fluid using the filling device 2100, it can be controlled separately according to the different cavities.

[0106] refer to Figure 8 This application provides a method for using a balloon dilation catheter. The balloon dilation catheter is the aforementioned balloon dilation catheter 1000 or the balloon dilation catheter 1000 of the aforementioned balloon pre-dilation system 2000. This method is used to dilate a balloon, and this method can be an operational method or a method for quality inspection.

[0107] The method S3000 for using a balloon dilation catheter may include steps S310 to S330.

[0108] In step S310, both the first balloon 21 and the second balloon 22 are inflated with filling fluid, causing both balloons 21 and 22 to expand and support the third balloon 23. Optionally, refer to... Figure 2 When both the first balloon 21 and the second balloon 22 are connected to the fluid delivery channel 110, the expansion of the first balloon 21 and the expansion of the second balloon 22 can occur simultaneously. (Reference) Figure 3 The first balloon 21 and the second balloon 22 are connected to different cavities, and different inflation flow rates can be set so that one inflates quickly and the other slowly. When the nominal diameters of the first balloon 21 and the second balloon 22 are different, different inflation fluid flow rates can also be used.

[0109] For example, without the third cavity 113, step S320 can be performed before step S330 to inflate the first balloon 21 and / or the second balloon 22, so that fluid flows from the fluid delivery channel 110 through the inner balloon into the outer balloon. This then achieves step S330, where the third balloon 23 is filled with inflation fluid, causing the third balloon 23 to expand.

[0110] In some other embodiments, where the balloon dilation catheter 1000 includes a third cavity 113, step S330 can be performed directly after step S310 without bursting the first balloon 21 and / or the second balloon 22, and filling fluid is introduced into the third balloon 23 through the third cavity 113 to dilate the third balloon 23.

[0111] Exemplarily, it may also include the step of extracting fluid from the third balloon 23.

[0112] The method for balloon dilation catheters described in this application is simple to operate and easy to execute. It can achieve one-step or two-stage expansion changes.

[0113] The technical features of the above-disclosed embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0114] In the embodiments disclosed above, unless otherwise explicitly specified and limited, the execution order of each step is not restricted. For example, they can be executed in parallel or sequentially in different orders. The sub-steps of each step can also be executed alternately. Various forms of processes described above can be used, and steps can be reordered, added, or deleted, as long as the desired result of the technical solution provided in this application can be achieved, and this application does not impose any restrictions here.

[0115] The embodiments disclosed above merely illustrate several implementation methods of this application, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of patent protection of this application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the scope of patent protection claimed by this application. Therefore, the scope of patent protection of this application should be determined by the appended claims.

Claims

1. A balloon dilation catheter, characterized in that, include: Pipe structure, including fluid transport channels; The first balloon is fixed to the tubular structure and connected to the fluid delivery channel; The second balloon is fixed to the tubular structure and is spaced from the first balloon along the proximal-distal direction; the second balloon is connected to the fluid delivery channel. as well as A third balloon is fixed to the tubular structure, and the third balloon encloses the first balloon and the second balloon.

2. The balloon dilation catheter according to claim 1, characterized in that, The burst pressure of the third balloon is greater than the burst pressure of at least one of the first balloon and the second balloon.

3. The balloon dilation catheter according to claim 1, characterized in that, The nominal shapes of the first balloon and the second balloon are both circular or elliptical; when both the first balloon and the second balloon are inflated, the portion of the third balloon located between the first balloon and the second balloon can be pulled up.

4. The balloon dilation catheter according to claim 1, characterized in that, The fluid delivery channel includes a first cavity and a second cavity, the first cavity being connected to the first balloon and the second cavity being connected to the second balloon.

5. The balloon dilation catheter according to claim 1, characterized in that, The fluid delivery channel further includes a third cavity, which is connected to the third balloon.

6. The balloon dilation catheter according to any one of claims 1 to 5, characterized in that, The wall thickness of the first balloon and at least one of the second balloons is less than the wall thickness of the third balloon.

7. A balloon pre-dilation system, characterized in that, include: The balloon dilation catheter as described in any one of claims 1 to 6; and A filling device is connected to the tube structure.

8. A method for using a balloon dilation catheter, wherein the balloon dilation catheter is a balloon dilation catheter according to any one of claims 1 to 6 or a balloon dilation catheter of the balloon pre-dilation system as described in claim 7, characterized in that, include: Both the first and second balloons are inflated with filling fluid, causing the first and second balloons to expand and support the third balloon.

9. The method for using a balloon dilation catheter according to claim 8, characterized in that, Also includes: The third balloon is inflated with filling fluid to cause it to expand.

10. The method for a balloon dilation catheter according to claim 9, characterized in that, Also includes: Inflate at least one of the first and second balloons, and inflate the third balloon with filling fluid through a cavity connected to the first and / or second balloons; Alternatively, filling fluid can be introduced through a cavity connected to the third balloon.

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