Balloon catheter assembly and delivery device

Abstract

The utility model provides a balloon catheter assembly and a conveying device. Different catheter sections of an inner catheter of the balloon catheter assembly are different in at least one of diameter and tensile yield force, and different catheter sections of an outer catheter are different in at least one of diameter and tensile yield force; the inner catheter is sleeved with the outer catheter, a fluid channel is formed by a catheter wall gap between the inner catheter and the outer catheter, the inner catheter is sleeved with the balloon body based on a balloon body inner cavity, and the balloon body inner cavity of the balloon body is communicated with the fluid channel. According to the balloon catheter assembly, the tensile yield force of the pipe section at the far end of the inner catheter or the outer catheter is improved, the safety of the small-diameter pipe section is ensured, and then the balloon catheter assembly can smoothly reach the target position.

Description

Balloon catheter assembly and delivery device Technical Field

[0001] This application relates to the field of medical device technology, and in particular to balloon catheter assemblies and delivery devices. Background Technology

[0002] Percutaneous coronary intervention (PCI) has developed rapidly and is one of the important methods for treating coronary heart disease. This treatment method mainly involves inserting a balloon dilator catheter through a guidewire to the lesion site in the coronary artery, and then inflating the balloon by applying pressure to dilate the blood vessel.

[0003] For distal coronary arteries, due to their tortuous nature and small diameter, interventional procedures have a lower success rate and a higher risk of restenosis compared to conventional coronary artery lesions, and are more prone to complications such as arrhythmias. Conventional products for treating calcified lesions, such as cutting balloons, spinous process balloons, plaque resection systems, and plaque rotational atherectomy systems, cannot easily reach the target location. In cases of severe coronary artery stenosis, such as CTO lesions, establishing a pathway for subsequent interventional treatment products presents a significant clinical challenge. Summary of the Invention

[0004] To address the aforementioned technical problems, embodiments of this application provide a balloon catheter assembly and a delivery device.

[0005] According to one aspect, this application provides a balloon catheter assembly comprising:

[0006] An internal conduit has an axially penetrating internal cavity, and at least one of the diameter and tensile yield strength of different sections of the internal conduit is different.

[0007] An outer conduit has an axially penetrating outer tube cavity inside. At least one of the diameter and tensile yield strength of different sections of the outer conduit is different. The outer conduit is sleeved on the outside of the inner conduit based on the outer tube cavity, and the gap between the outer tube wall of the inner conduit and the inner tube wall of the outer conduit forms a fluid channel.

[0008] The balloon body has an internal cavity and a distal and proximal port connecting the internal cavity. The balloon body is fitted over the internal catheter based on the internal cavity. The distal port of the balloon body is connected to the internal catheter. A guiding element is installed at the distal end of the internal catheter. The distal port of the balloon body is sealed to the guiding element. The proximal port of the balloon body is connected to the external catheter. The internal cavity of the balloon body is connected to the fluid channel.

[0009] In one embodiment, the inner catheter is provided with an inner guidewire hole, which communicates with the inner tube cavity of the inner catheter;

[0010] The external catheter is provided with an external guide wire hole, which is sealed and connected to the internal guide wire hole, and both the external guide wire hole and the internal guide wire hole are sealed and isolated from the fluid channel.

[0011] In one embodiment, the internal catheter includes an axially connected distal internal segment and a proximal internal segment, the diameter of the distal internal segment being smaller than the diameter of the proximal internal segment; and / or,

[0012] The external catheter consists of an axially connected distal external tube segment and a proximal external tube segment, with the diameter of the distal external tube segment being smaller than that of the proximal external tube segment.

[0013] In one embodiment, the inner catheter has a diameter reduction section between the distal and proximal inner catheter segments; and / or,

[0014] There is a diameter reduction section between the distal and proximal ends of the external catheter; and / or,

[0015] The tensile yield strength of the distal inner tube segment is greater than that of the proximal inner tube segment; and / or,

[0016] The tensile yield strength of the distal outer pipe section is greater than that of the proximal outer pipe section; and / or,

[0017] The diameter of the distal inner pipe section is less than or equal to 0.53 mm; and / or,

[0018] The diameter of the distal outer pipe section is less than or equal to 0.74 mm; and / or,

[0019] The ratio of the diameter of the proximal inner tube segment to the diameter of the distal inner tube segment is between 1.3 and 1.7; and / or,

[0020] The ratio of the diameter of the proximal outer pipe section to the diameter of the distal outer pipe section is between 1.3 and 1.7.

[0021] In one embodiment, the balloon body comprises at least a distal balloon segment and a proximal balloon segment in the direction from the distal lumen to the proximal lumen, and the length of the distal balloon segment is greater than the length of the proximal balloon segment.

[0022] In one embodiment, the ratio of the length of the distal segment of the balloon to the length of the proximal segment is between 3 and 10; and / or,

[0023] From the distal to the proximal opening, the balloon body comprises a distal segment, a mid-segment, and a proximal segment, with the ratio of the length of the distal segment to the length of the mid-segment greater than 0.5; and / or,

[0024] From the distal end of the balloon sac to the proximal end, the cross-sectional profile of the distal segment gradually decreases; and / or,

[0025] From the distal end of the balloon to the proximal end, the cross-sectional profile of the balloon gradually increases.

[0026] In one embodiment, the distal segment of the balloon is configured as a cone, and the cone angle at the distal end of the distal segment is between 1° and 15°; and / or,

[0027] The distal segment of the balloon is configured as a cone, with its diameter gradually decreasing from the distal opening to the proximal opening; and / or,

[0028] The proximal segment of the balloon is configured as a cone, with the diameter of the proximal segment gradually increasing from the distal end to the proximal end.

[0029] In one embodiment, the capsule wall thickness is between 7 μm and 15 μm; and / or,

[0030] The length of the mid-segment of the balloon body is 0.5cm to 1.5cm from the distal to the proximal opening.

[0031] In one embodiment, the distal end of the balloon body is sealed to the distal end of the inner catheter, and the proximal end of the balloon body is sealed to the distal end of the outer catheter; and / or,

[0032] The internal catheter is equipped with a radiopaque element, which is located within the endoscopic cavity of the balloon body; and / or,

[0033] A thiocyanate tube is installed at the proximal end of the external catheter, and a support is installed at the proximal end of the thiocyanate tube. The support is connected to a grip handle.

[0034] According to another aspect, this application provides a delivery device that includes a balloon catheter assembly.

[0035] In the balloon catheter assembly and delivery device of this application, the diameters and tensile yield forces (tensile mechanical properties) of different segments of the inner or outer catheter are innovatively designed. This allows the inner or outer catheter to balance pushing force and compliance. For example, the distal inner and outer segments improve passability, while the proximal inner and outer segments enhance pushing force. This design of different diameters and tensile yield forces can be achieved through an oriented stretching process, increasing the tensile yield force of the distal segments of the inner or outer catheter by 1.5-2 times. That is, the tensile yield force of the stretched portion is 1.5 to 2 times higher than that of the unstretched portion. The smaller diameter of the distal segment enhances the passability of the product, allowing the balloon to reach the target location more smoothly; while the higher tensile mechanical properties avoid the risk of product breakage in the blood vessel due to the pull-back force applied by the operator during the withdrawal process, ensuring product safety and guaranteeing the smooth arrival of the product at the target location. Attached Figure Description

[0036] Other features and advantages of this application will be better understood through the following detailed description of optional embodiments in conjunction with the accompanying drawings, in which the same reference numerals denote the same or similar parts, wherein:

[0037] Figure 1 is a schematic diagram of the structure of a conveying device provided in one embodiment of this application.

[0038] Figure 2 is a partially enlarged schematic diagram of the conveying device shown in Figure 1.

[0039] Figure 3 is a schematic diagram of the structure of the balloon body of the delivery device shown in Figure 1.

[0040] Figure 4 is a schematic diagram of the folded structure of the balloon as shown in Figure 3.

[0041] Figure 5 is a rendering of the folded wing of the balloon as shown in Figure 3. Detailed Implementation

[0042] 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.

[0043] In this application, tensile yield strength refers to tensile mechanical properties, such as axial yield strength, etc. The reduction ratio refers to the ratio of the diameter before reduction to the diameter after reduction.

[0044] Referring to Figures 1 to 5, this application provides a delivery device including a balloon catheter assembly. The delivery device integrates a balloon catheter, guidewire channel, and pressurization system, and is compatible with standard interventional instruments. An ergonomic handle can be designed to support precise delivery and pressure control. Regarding the balloon catheter assembly, it may include an inner catheter 1000, an outer catheter 2000, and a balloon body 3000. The inner catheter 1000 has an axially penetrating inner tube cavity, and at least one of the diameter and tensile yield strength of different segments of the inner catheter 1000 is different. The outer catheter 2000 has an axially penetrating outer tube cavity, and at least one of the diameter and tensile yield strength of different segments of the outer catheter 2000 is different. The outer catheter 2000 is sleeved outside the inner catheter 1000 based on the outer tube cavity, and the wall gap between the outer wall of the inner catheter 1000 and the inner wall of the outer catheter 2000 forms a fluid channel 1300.

[0045] The balloon body 3000 has an inner cavity and a distal port 3001 and a proximal port 3002 communicating with the inner cavity. The balloon body 3000 is fitted over the inner catheter 1000 based on the inner cavity. The distal port 3001 of the balloon body 3000 is connected to the inner catheter 1000, and the proximal port 3002 of the balloon body 3000 is connected to the outer catheter 2000. The inner cavity of the balloon body 3000 is in communication with the fluid channel 1300. In one embodiment, the inner catheter 1000 has an inner guidewire hole that communicates with the inner tube cavity of the inner catheter 1000. The outer catheter 2000 has an outer guidewire hole that is sealed and communicates with the inner guidewire hole, and both the outer and inner guidewire holes are sealed and isolated from the fluid channel 1300. The inner and outer guide wire holes can be sealed by laser welding or hot air welding to form an independent guide wire channel (inner tube cavity) and a physical isolation between the fluid channel 1300 (tube wall gap), avoiding cross-contamination. Both the inner and outer guide wire holes can be smoothed after cutting to reduce the resistance of the guide wire passage.

[0046] In the structural design of the inner conduit 1000 and the outer conduit 2000 described above, the inner conduit 1000 and the outer conduit 2000 can be designed in segments, so that different segments of the inner conduit 1000 have different diameters and tensile yield forces, and different segments of the outer conduit 2000 also have different diameters and tensile yield forces. It should be noted that since the inner conduit 1000 and the outer conduit 2000 are assembled by interlocking, the diameters of different segments of the inner conduit 1000 and the outer conduit 2000 can be designed to match each other, so that the corresponding segments of the inner conduit 1000 and the outer conduit 2000 can be adapted to each other.

[0047] For example, in one embodiment, if the inner catheter 1000 is defined to include an axially connected distal inner catheter segment 1100 and a proximal inner catheter segment 1200, the diameter of the distal inner catheter segment 1100 is smaller than the diameter of the proximal inner catheter segment 1200. If the outer catheter 2000 is defined to include an axially connected distal outer catheter segment 2100 and a proximal outer catheter segment 2200, the diameter of the distal outer catheter segment 2100 is smaller than the diameter of the proximal outer catheter segment 2200.

[0048] Therefore, referring to Figure 2, in the inner catheter 1000 and the outer catheter 2000, the distal segment diameter of the inner catheter 1000 or the outer catheter 2000 is smaller (e.g., the distal segment diameter D1 of the outer catheter 2000 is ≤0.74 mm, and the distal segment diameter D2 of the inner catheter 1000 is ≤0.53 mm), while the proximal segment diameter of the inner catheter 1000 or the outer catheter 2000 is larger (diameter ratio 1.3-1.7). In one embodiment, the diameter of the distal inner segment 1100 is less than or equal to 0.53 mm, the diameter of the distal outer segment 2100 is less than or equal to 0.74 mm, the ratio of the diameter of the proximal inner segment 1200 to the diameter of the distal inner segment 1100 is between 1.3 and 1.7, and the ratio of the diameter of the proximal outer segment 2200 to the diameter of the distal outer segment 2100 is between 1.3 and 1.7.

[0049] The aforementioned structural design of the inner catheter 1000 or outer catheter 2000 balances pushing force and flexibility. Specifically, the distal inner catheter segment 1100 and distal outer catheter segment 2100 improve throughput, while the proximal inner catheter segment 1200 and proximal outer catheter segment 2200 enhance pushing force. Furthermore, the distal inner catheter segment 1100 and distal outer catheter segment can employ a gradually transitioning diameter design to reduce stress concentration. This design with different diameters can be achieved through an oriented stretching process, increasing the tensile yield strength of the distal catheter segment. For example, increasing the tensile yield strength by 1.5-2 times ensures the safety of the small-diameter segment. The balloon body 3000 is pressurized and inflated through the fluid channel 1300, and its segmented connection design also optimizes sealing and pressure transmission efficiency.

[0050] In one embodiment, the inner conduit 1000 has a diameter-changing section between its distal inner tube segment 1100 and proximal inner tube segment 1200, causing a gradual change in diameter between the two segments to avoid stress concentration. Similarly, the outer conduit 2000 has a diameter-changing section between its distal outer tube segment 2100 and proximal outer tube segment 2200, causing a gradual change in diameter between the two segments to avoid stress concentration.

[0051] In one embodiment, the tensile yield force of the distal inner pipe section 1100 may be greater than that of the proximal inner pipe section 1200, and the tensile yield force of the distal outer pipe section 2100 may be greater than that of the proximal outer pipe section 2200. Therefore, in the inner and outer pipe sections, the distal inner pipe section 1100 and the distal outer pipe section 2100 can be stretched and formed by a mold (e.g., at a temperature of 70-160°C and a diameter reduction ratio of about 1.5), so that the molecular chains of the material are aligned and the tensile strength of the distal inner pipe section 1100 and the distal outer pipe section 2100 is improved. Furthermore, since the ratio of the diameter of the proximal inner pipe section 1200 to the diameter of the distal inner pipe section 1100 is between 1.3 and 1.7, and the ratio of the diameter of the proximal outer pipe section 2200 to the diameter of the distal outer pipe section 2100 is between 1.3 and 1.7, controlling the above diameter ratio within the range of 1.3-1.7 can effectively balance mechanical properties and dimensional adaptability.

[0052] Regarding the aforementioned balloon body 3000, in one embodiment, the balloon body 3000 may include at least a distal balloon segment 3100 and a proximal balloon segment 3300 in the direction from the distal opening 3001 to the proximal opening 3002, and the length of the distal balloon segment 3100 may be greater than the length of the proximal balloon segment 3300. For example, in one embodiment, the ratio of the length of the distal balloon segment 3100 to the length of the proximal balloon segment 3300 is between 3 and 10. Furthermore, the direction from the distal opening 3001 to the proximal opening 3002 can be defined. The balloon body 3000 includes a distal balloon segment 3100, a mid-balloon segment 3200, and a proximal balloon segment 3300. Referring to Figure 3, the length of the distal balloon segment 3100 can be represented by L1, the length of the mid-balloon segment 3200 can be represented by L2, and the length of the proximal balloon segment 3300 can be represented by L3. The approximate proportions in Figure 3 can then be observed based on L1, L2, and L3.

[0053] At this point, the aforementioned three-segment balloon design (distal, mid, and proximal) optimizes pressure distribution. The distal segment 3100 tapers (e.g., a cone) to facilitate access to the stenosis, the mid segment 3200 provides stable support, and the proximal segment 3300 expands (e.g., a reverse cone angle) to prevent balloon displacement. The ratio of the length of the distal segment 3100 to the length of the mid segment 3200 is greater than 0.5, ensuring uniform expansion. Based on this design, it facilitates penetration into the stenotic lesion, and the gradual expansion of the distal segment 3100 during inflation creates a progressive dilation effect, reducing the risk of vascular injury.

[0054] Furthermore, from the distal opening 3001 to the proximal opening 3002, the cross-sectional profile of the distal segment 3100 of the balloon gradually decreases; for example, the distal segment 3100 is configured as a cone, and its diameter gradually decreases from the distal opening 3001 to the proximal opening 3002. Conversely, from the distal opening 3001 to the proximal opening 3002, the cross-sectional profile of the proximal segment 3300 of the balloon gradually increases; for example, the proximal segment 3300 is configured as a cone, and its diameter gradually increases from the distal opening 3001 to the proximal opening 3002.

[0055] Referring again to Figure 3, if the distal segment 3100 of the balloon is configured as a cone, the cone angle α at the distal end of the distal segment 3100 can be limited to between 1° and 15°. A very small cone angle (e.g., α = 1°) allows the distal end of the distal segment 3100 to form a "drill" effect, which, combined with high-mechanical-performance catheter advancement, can penetrate CTO lesions. The reverse cone angle (gradually increasing diameter) of the proximal segment 3300 of the balloon enhances the anchoring effect and prevents balloon retraction. In one embodiment, the balloon body 3000 has a wall thickness between 7 μm and 15 μm. Compared to other parts, the balloon body 3000 is relatively flexible. Because the balloon body 3000 is located at the most distal end, the longer this flexible end, the stronger its ability to navigate the tortuous and bifurcated parts of the blood vessel. The length of the balloon body 3000 from the distal lumen 3001 to the proximal lumen 3002 is 1 cm to 3 cm. The mid-segment of the balloon (3200) has a length of 0.5cm to 1.5cm. The ultra-thin balloon wall (less than 30μm thick in both sections) of the balloon body (3000) enhances flexibility, and the total length of 1cm to 3cm can accommodate distal vascular anatomy.

[0056] The distal lumen 3001 of the balloon body 3000 is sealed and connected to the distal end of the inner catheter 1000, and the proximal lumen 3002 of the balloon body 3000 is sealed and connected to the distal end of the outer catheter 2000. A guiding element 4000 is located at the distal end of the inner catheter 1000, and the distal lumen 3001 of the balloon body 3000 is sealed and connected to the guiding element 4000. A contrast-enhancing element 5000 is located within the balloon body 3000's internal cavity. The contrast-enhancing element 5000 (e.g., a platinum-iridium ring) is located within the internal cavity of the balloon body 3000 for easy intraoperative positioning. A hypotube 6000 is located proximally at the outer catheter 2000, and a support 7000 is located proximally at the hypotube 6000. The support 7000 is connected to a handle 8000. The hypotube 6000 and the handle 8000 are fixed together with adhesive to provide operational stability.

[0057] This application provides a method for manufacturing a balloon catheter assembly, wherein at least one of the inner catheter 1000 and the outer catheter 2000 of the balloon catheter assembly is subjected to orientation stretching treatment, such that at least one of the diameter and tensile yield force of different segments of the inner catheter 1000 is different, or such one of the diameter and tensile yield force of different segments of the outer catheter 2000 is different.

[0058] By employing the principle of oriented stretching, targeted self-reinforcement treatment can be applied to different segments of the inner catheter 1000 or outer catheter 2000. After oriented stretching treatment, the segment's tensile yield strength is increased while its outer diameter is reduced, allowing the balloon catheter assembly to be safely pushed to the distal end of smaller blood vessels and facilitating access to lesion stenosis. Therefore, the above steps mainly involve oriented stretching treatment of certain segments of the inner catheter 1000 and outer catheter 2000, creating differences in diameter and tensile yield strength among different segments.

[0059] For the above-mentioned orientation stretching process, please refer to the following steps:

[0060] The mandrel is inserted into the original tube, and the front end is pre-treated (cut or pre-stretched). The tapered section is inserted into the mold (the aperture is set according to the target outer diameter). It is heated (70-160℃) and stretched, with a diameter reduction ratio of approximately 1.5, at a medium to high traction speed. After cooling and shaping, a high-strength, small-diameter tube section is formed. This process reduces the distal outer diameter to 0.53mm (inner tube 1000) or 0.74mm (outer tube 2000), while increasing the tensile yield strength by 1.5-2 times.

[0061] In one embodiment, a mandrel with a size smaller than the inner diameter of the inner conduit 1000 and the outer conduit 2000 can be selected according to processing requirements and inserted into the inner conduit 1000 or the outer conduit 2000. Then, the distal end of the inner conduit 1000 or the outer conduit 2000 is pre-treated by cutting or stretching to make the distal segment of the inner conduit 1000 or the outer conduit 2000 thinner. The thinned segment constitutes the distal inner segment 1100 of the inner conduit 1000 or the distal outer segment 2100 of the outer conduit 2000.

[0062] The tapered tube segment is inserted into a metal mold with a defined aperture, the inner diameter of which is determined by the desired outer diameter of the inner conduit 1000 or outer conduit 2000. The metal mold is then fixed within the heating jacket of a stretching machine. The distal tapered tube segment of the inner conduit 1000 or outer conduit 2000 is held by the stretching machine's traction head. Stretching parameters are set, and stretching is then performed. For example, the stretching parameters can be set as follows: temperature approximately 70°C to 160°C, speed adjusted to medium-high, and a reduction ratio of approximately 1.5.

[0063] Using the above processing method, the outer diameter of the outer catheter 2000 can be controlled to below 0.74 mm, and the outer diameter of the inner catheter 1000 can be controlled to below 0.53 mm. At the same time, the yield strength of the inner catheter 1000 or the outer catheter 2000 increases to 1.5 to 2 times the original value.

[0064] In a specific embodiment, the orientation stretching treatment method for the inner catheter 1000 and the outer catheter 2000 can refer to the following steps:

[0065] Select a mandrel with a size smaller than the inner diameter of the inner conduit 1000 and the outer conduit 2000, insert it into the original, unstretched inner conduit 1000 or outer conduit 2000, then cut or cold-draw the front end of the inner conduit 1000 or outer conduit 2000 to make the front end of the inner conduit 1000 or outer conduit 2000 thinner, and then insert the thinned part of the front end of the inner conduit 1000 or outer conduit 2000 into a metal mold with a defined aperture. The inner diameter of the metal mold is determined according to the expected outer diameter of the inner conduit 1000 or outer conduit 2000.

[0066] The metal mold is fixed in the heating jacket of the stretching machine. The front end of the inner guide tube 1000 or the outer guide tube 2000 is held by the traction head of the stretching machine. After setting the stretching parameters, stretching is performed. For example, the stretching parameter range can be referenced as follows: temperature is about 70℃ to 160℃, speed is adjusted to medium to high, and the diameter reduction ratio is about 1.5.

[0067] Under these conditions, the molecular chains and segments of block polyether amide, which are the main components of the inner conduit 1000 and the outer conduit 2000, will rearrange along the direction of the force under the action of external tension. Macroscopically, this manifests as the inner conduit 1000 and the outer conduit 2000 becoming thinner and longer, and the tensile strength of the inner conduit 1000 and the outer conduit 2000 increasing.

[0068] Using this method, the outer diameter of the outer catheter 2000 can be controlled to below 0.74 mm, and the outer diameter of the inner catheter 1000 can be controlled to below 0.53 mm, while the tensile yield strength of the inner catheter 1000 and the outer catheter 2000 increases to 1.5 to 2 times the original value.

[0069] It should be noted that the orientation process typically generates residual stress. After the external force is removed, this residual stress causes the straightened and elongated chains in the stretched inner conduit 1000 and outer conduit 2000 to tend to return to their original free state with changes in operating and ambient temperatures; that is, the molecular chains curl, and the inner conduit 1000 and outer conduit 2000 deform. To overcome this problem, in one example of this application, after the inner conduit 1000 and outer conduit 2000 undergo orientation treatment, the stretched inner conduit 1000 and outer conduit 2000 are inserted into a mandrel of appropriate size and placed in a drying oven for annealing at a temperature of 65°C to 100°C for approximately 0.5 hours.

[0070] Referring to Figures 4 and 5, after the balloon body 3000 is folded, it can be in the state shown in Figure 5, with the folded wings tightly wrapped around the inner catheter 1000. Because the inner catheter 1000 has undergone orientation stretching treatment, the outer diameter D3 of the inner catheter 1000 can be less than 0.6 mm. At the same time, the length of the balloon body 3000 can be represented by L4, and the length of this soft segment is more than 1.5 times that of a conventional balloon.

[0071] In the embodiments of this application, the balloon catheter assembly has a minimum outer diameter and a relatively long, flexible segment at the lesion site, making it easier to reach the stenosis through tortuous, bifurcated, and small blood vessels, and more easily through narrow blood vessel stenosis. The distal long conical structure of the balloon body 3000 has a minimum cone angle (the cone angle α when the balloon is inflated can be controlled to a minimum of 1°), making it easier to penetrate the vascular stenosis. In other words, through the balloon catheter assembly design of this application, the goal of opening more clinically complex vascular stenosis sites through balloon dilation is achieved.

[0072] Although the outer diameter of the portion passing through the lesion site is reduced, its mechanical properties are improved to more than 1.5 times the original, overcoming the risk of breakage of small-diameter pipes and improving the safety and effectiveness of the product in clinical use.

[0073] To demonstrate this, a simulated usage study was conducted, and the results are as follows:

[0074] (1) It has a stronger ability to bifurcate blood vessels.

[0075] Under identical conditions—a 37°C water bath, identical simulated blood vessels (with bifurcations at different angles: 90°, 120°, and 150°)—and guided by the same guidewire, the balloon catheter assembly of this application and a conventional product were traversed through bifurcations at different angles. The results showed that the balloon catheter assembly of this application could successfully traverse the 90° and 120° bifurcations; the conventional product could successfully traverse the 90° bifurcation, but when traversing the 120° bifurcation, the balloon would become stuck at the bifurcation. Therefore, the balloon catheter provided by this application has a better ability to traverse blood vessel bifurcations. Repeating the experiment with different operators yielded the same results.

[0076] (2) Capable of treating severe stenosis of distal blood vessels

[0077] Under identical conditions—a 37°C water bath, the same simulated blood vessel (with a CTO lesion simulation block), and the same guidewire—the balloon catheter assembly of this application and a conventional product were tested using a tunneling method to pass through a severely stenotic area (CTO lesion simulation block) in the distal end of the simulated blood vessel. The balloon catheter assembly provided by this application could successfully pass through the CTO lesion simulation block, while the conventional product could not. This demonstrates that the balloon catheter assembly provided by this application has the ability to pass through severely stenotic distal blood vessels. Repeating the test with different operators yielded the same results.

[0078] The tunneling method employed involves pushing the balloon catheter assembly to the CTO lesion simulation block until it can no longer be pushed, inflating the balloon body 3000, slightly enlarging the CTO lesion area that contacts the distal cone of the balloon body 3000, and then withdrawing the balloon body 3000 to return it to its original clamped state. The balloon catheter assembly is then pushed deeper into the CTO lesion until it can no longer be pushed, and the inflation and withdrawal of the balloon body 3000 is repeated.

[0079] The above results demonstrate that the balloon catheter assembly provided in this application can successfully navigate through tortuous and bifurcated vessels to reach the distal stenosis in cases of severe distal vascular stenosis. Furthermore, it can penetrate severely stenotic areas using a tunneling method, establishing a pathway for subsequent interventional treatment products. Simulation experiments show that the catheter of this application achieves a 100% success rate in penetrating 90° and 120° bifurcated vessels, while traditional catheters only penetrate at 90°. In a CTO lesion model, the balloon catheter assembly provided in this application successfully penetrated the lesion using a tunneling method (inflation-retraction cycle), while traditional catheters failed. Data confirms that the balloon catheter assembly of this application combines the advantages of small outer diameter and high mechanical performance with an optimized balloon structure, significantly improving clinical applicability and providing a solution for complex lesions such as severe vascular stenosis.

[0080] The technical features of the above 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.

[0081] The embodiments described above are merely illustrative of 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 the patent 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 protection scope of this application. Therefore, the protection scope of this patent application should be determined by the appended claims.

Claims

1. A balloon catheter assembly, characterized in that, The balloon catheter assembly includes: an inner catheter having an axially penetrating inner cavity, wherein at least one of the diameter and tensile yield strength of different segments of the inner catheter is different; an outer catheter having an axially penetrating outer cavity, wherein at least one of the diameter and tensile yield strength of different segments of the outer catheter is different; the outer catheter is sleeved on the outside of the inner catheter based on the outer cavity, and the wall gap between the outer wall of the inner catheter and the inner wall of the outer catheter forms a fluid channel; and a balloon body having an inner cavity and a distal orifice and a proximal orifice communicating with the inner cavity, the balloon body being sleeved on the outside of the inner catheter based on the inner cavity, the distal orifice of the balloon body being connected to the inner catheter, a guide element being disposed at the distal end of the inner catheter, the distal orifice of the balloon body being sealed to the guide element, the proximal orifice of the balloon body being connected to the outer catheter, and the inner cavity of the balloon body communicating with the fluid channel.

2. The balloon catheter assembly according to claim 1, characterized in that, The inner catheter is provided with an inner guide wire hole, which is connected to the inner tube cavity of the inner catheter; the outer catheter is provided with an outer guide wire hole, which is sealed and connected to the inner guide wire hole, and both the outer guide wire hole and the inner guide wire hole are sealed and isolated from the fluid channel.

3. The balloon catheter assembly according to claim 1, characterized in that, The inner catheter comprises an axially connected distal inner tube segment and a proximal inner tube segment, the diameter of the distal inner tube segment being smaller than the diameter of the proximal inner tube segment; and / or, the outer catheter comprises an axially connected distal outer tube segment and a proximal outer tube segment, the diameter of the distal outer tube segment being smaller than the diameter of the proximal outer tube segment.

4. The balloon catheter assembly according to claim 3, characterized in that, The inner catheter has an inner diameter transition section between its distal and proximal inner segments; and / or, the outer catheter has an outer diameter transition section between its distal and proximal outer segments; and / or, the tensile yield strength of the distal inner segment is greater than that of the proximal inner segment; and / or, the tensile yield strength of the distal outer segment is greater than that of the proximal outer segment; and / or, the diameter of the distal inner segment is less than or equal to 0.53 mm; and / or, the diameter of the distal outer segment is less than or equal to 0.74 mm; and / or, the ratio of the diameter of the proximal inner segment to the diameter of the distal inner segment is between 1.3 and 1.7; and / or, the ratio of the diameter of the proximal outer segment to the diameter of the distal outer segment is between 1.3 and 1.

7.

5. The balloon catheter assembly according to claim 1, characterized in that, From the distal opening to the proximal opening, the balloon body includes at least a distal balloon segment and a proximal balloon segment, and the length of the distal balloon segment is greater than the length of the proximal balloon segment.

6. The balloon catheter assembly according to claim 5, characterized in that, The ratio of the length of the distal segment of the balloon to the length of the proximal segment is between 3 and 10; and / or, in the direction from the distal opening to the proximal opening, the balloon body includes a distal segment, a middle segment, and a proximal segment, and the ratio of the length of the distal segment to the length of the middle segment is greater than 0.5; and / or, in the direction from the distal opening to the proximal opening, the cross-sectional profile of the distal segment of the balloon gradually decreases; and / or, in the direction from the distal opening to the proximal opening, the cross-sectional profile of the proximal segment of the balloon gradually increases.

7. The balloon catheter assembly according to claim 6, characterized in that, The distal segment of the balloon is configured as a cone, and the cone angle at the distal end of the distal segment is between 1° and 15°; and / or, the distal segment of the balloon is configured as a cone, and the diameter of the distal segment gradually decreases from the distal opening to the proximal opening; and / or, the proximal segment of the balloon is configured as a cone, and the diameter of the proximal segment gradually increases from the distal opening to the proximal opening; and / or, the length of the mid-segment of the balloon is between 0.5 cm and 1.5 cm.

8. The balloon catheter assembly according to claim 1, characterized in that, The balloon body has a wall thickness between 7 μm and 15 μm; and / or, the length of the balloon body is between 1 cm and 3 cm in the direction from the distal end to the proximal end.

9. The balloon catheter assembly according to claim 1, characterized in that, The distal end of the balloon body is sealed to the distal end of the inner catheter, and the proximal end of the balloon body is sealed to the distal end of the outer catheter; and / or, the inner catheter is provided with a radiopaque element, which is located in the inner cavity of the balloon body. And / or, a thiocyanate tube is provided at the proximal end of the external catheter, and a support portion is provided at the proximal end of the thiocyanate tube, the support portion being connected to a grip handle.

10. A conveying device, characterized in that, The delivery device includes a balloon catheter assembly as described in any one of claims 1-9.

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