Balloon dilatation catheter

Abstract

The utility model belongs to the technical field of balloon catheter, and relates to a balloon dilatation catheter, which comprises an outer tube, a balloon end assembly fixedly arranged at the front end of the outer tube, an inner tube coaxially sleeved in the inner part of the outer tube, an annular space formed by the outer tube and the inner tube, two isolators arranged between the outer tube and the inner tube along the axial direction, and the annular space is accurately divided into an inflation cavity and a reagent channel; a guide wire cavity tube penetrates through the whole tube body to provide a path for the movement of the guide wire; a catheter seat is fixedly sleeved at the proximal end of the tube body, the catheter seat is provided with an inner channel, and the two ends of the inner channel are respectively communicated with a second taper joint and the reagent channel; a guide wire is movably penetrated in the guide wire channel, the shape of a sealing assembly is matched with the cross-sectional shape of the connection part of the guide wire channel and the inflation cavity, the guide wire can be moved to the inlet of the inflation cavity in the guide wire channel under the driving of the guide wire, and the guide wire is movably sealed between the guide wire channel and the inflation cavity. The sealing property of the inflation cavity can be effectively maintained, the balloon can be continuously kept in the expanded state, and the treatment effect is improved.

Description

Technical Field

[0001] This utility model relates to the field of balloon catheter technology, and in particular to a balloon dilation catheter. Background Technology

[0002] In modern interventional medicine, balloon catheters play a crucial role as a key tool in endovascular angioplasty. In the treatment of coronary atherosclerotic heart disease and other vascular stenosis conditions, doctors, guided by precise medical imaging equipment, skillfully deliver a balloon catheter to the narrowed area of ​​the blood vessel using percutaneous puncture techniques. Here, by inflating the balloon, the previously narrowed blood vessel is effectively dilated, successfully restoring the lumen diameter and significantly increasing blood flow, creating favorable conditions for subsequent stent implantation. Furthermore, after successful stent implantation, post-dilation with the balloon is necessary to prevent restenosis and ensure the durability of the treatment effect.

[0003] However, the balloon catheters widely used in the market have revealed a series of prominent problems in practical applications. Existing balloon catheters have a relatively simple structural design, typically equipped with only two channels. One channel connects to the inside of the balloon and is specifically responsible for balloon inflation, ensuring the balloon can expand and contract as expected. The other channel serves to allow the guidewire or contrast agent / medication to pass through. However, in actual use, when the guidewire is placed inside the catheter, it inevitably blocks the contrast agent channel. This makes it impossible to simultaneously allow the guidewire to function normally inside the catheter and allow the contrast agent or medication to pass through smoothly. For example, in some complex vascular disease treatment scenarios, doctors need to guide the balloon catheter to a designated position with the guidewire while simultaneously using contrast agent to clearly observe the internal condition of the blood vessel for precise operation. This limitation of existing balloon catheters forces doctors to frequently switch procedures, first withdrawing the guidewire to inject contrast agent, observing, and then reinserting the guidewire to advance the balloon catheter. This significantly increases the complexity and time cost of the surgical procedure, and also increases the surgical risk to some extent, adversely affecting the patient's treatment outcome and safety. Despite previous explorations and attempts by industry professionals to address this issue—for example, some researchers have tried to improve the internal structure of the catheter and adopt special shunt designs to ensure the unobstructed flow of contrast agents even when the guidewire passes through—while these designs alleviate the problem to some extent, they have made the manufacturing process of balloon catheters extremely complex, significantly increasing production costs. Moreover, the increased structural complexity reduces the reliability of the catheter during use, making it prone to new problems such as blockage and leakage, failing to fundamentally achieve a balance between performance improvement and cost control. Therefore, developing a new type of balloon catheter that can effectively solve the functional limitations of existing balloon catheters while also being cost-effective is of vital practical significance and urgent market demand for promoting the further development of endovascular angioplasty and improving patient treatment outcomes and safety. Summary of the Invention

[0004] Therefore, the technical problem to be solved by this utility model is to overcome the problem of poor balloon retention force in the existing balloon catheter, which is not conducive to continuous use, and thus provides a balloon dilation catheter.

[0005] To solve the above-mentioned technical problems, this utility model provides a balloon dilation catheter, comprising: The outer tube has a balloon end assembly fixedly installed at its front end, and an inner tube coaxially sleeved inside the outer tube. The outer and inner tubes enclose an annular space, and two isolators are arranged axially between them to precisely divide the annular space into an inflation chamber and a reagent channel. The guidewire lumen runs through the entire tube body, providing a path for the guidewire's movement. A catheter seat is fixedly sleeved at the proximal end of the tube body. The catheter seat has an inner channel, and its two ends are connected to the second conical connector and the reagent channel, respectively.

[0006] A guidewire, which moves through the guidewire lumen, has a smooth coating on its surface to reduce friction when moving within the lumen. A tip is located at the distal end of the guidewire and is securely connected to the distal end of the tube via a specific welding process, ensuring the stability of the connection during operation. A sealing assembly is located at the proximal end of the guidewire. The shape of the sealing assembly matches the cross-sectional shape of the connection between the guidewire lumen and the inflation chamber. Driven by the guidewire, it moves within the guidewire lumen to the inlet of the inflation chamber, movably sealing between the guidewire lumen and the inflation chamber. The sealing assembly is made of a material with good flexibility and sealing properties, ensuring a tight seal. The injection mechanism includes: first conical connectors respectively disposed on both sides of the tube body, the ends of the first conical connectors being connected to a balloon.

[0007] In one embodiment of the present invention, the tube body includes a guide wire cavity tube and an outer tube coaxially sleeved together. An annular space is formed between the outer tube and the guide wire cavity tube. Two isolation members are arranged axially between the guide wire cavity tube and the outer tube, so that the annular space is divided into an inflation chamber and a reagent channel.

[0008] In one embodiment of this utility model, the reagent channel penetrates the side wall of the outer tube at its distal end; the proximal end of the reagent channel is connected to the second conical connector, thereby achieving effective connection between the channels.

[0009] In one embodiment of this utility model, both the first conical connector and the second conical connector are provided with interfaces. The interface of the first conical connector is used to connect an external inflation / deflation device to realize the inflation and deflation operations of the balloon; the interface of the second conical connector is used to connect an external contrast agent injection device or a drug injection device to meet the needs of clinical contrast imaging and drug delivery.

[0010] The above-mentioned technical solution of this utility model has the following advantages compared with the prior art: This invention relates to a balloon dilation catheter, specifically designed for guidewire passage via a guidewire lumen. The guidewire plays a crucial role, providing strong support for the balloon catheter to penetrate the blood vessel smoothly, laying the foundation for subsequent procedures. The distal tip precisely limits the guidewire's position, ensuring stable movement of the balloon catheter within the blood vessel. When the balloon catheter reaches the narrowed area, the connection between the first tapered connectors on both sides of the catheter and the balloon allows for convenient inflation, causing the balloon to rapidly expand and effectively dilate the narrowed blood vessel. Simultaneously, the sealing component located at the proximal end of the guidewire can be pushed to its contact position with the guidewire lumen during operation, forming a reliable seal for the inflation chamber. This design effectively maintains the airtightness of the inflation chamber, ensuring the balloon remains inflated and reshapes the vessel within a predetermined time, thus improving treatment efficacy. During this period, due to the presence of other channels such as the reagent channel, an external contrast agent injection device or drug injection device can be connected simultaneously to achieve synchronous injection of contrast agent or drug. This technological breakthrough enables parallel balloon inflation, angiography, and drug delivery operations, eliminating the need for repeated catheter insertion and removal from the vessel, greatly improving treatment efficiency, reducing patient discomfort and infection risks, and providing a more efficient and safer solution for interventional vascular treatment. Attached Figure Description

[0011] To make the content of this utility model easier to understand, the present utility model will be further described in detail below with reference to specific embodiments and accompanying drawings. Figure 1 This is a planar sectional view of the balloon catheter of this utility model; Figure 2 This is a side sectional view of the balloon catheter of this utility model; Figure 3 This is a front view of the balloon catheter of this utility model; Figure 4 This is a utility model Figure 1 Enlarged view of point A in the middle; Figure 5 This is a utility model Figure 1 Enlarged view of point B in the middle; Explanation of reference numerals in the accompanying drawings: 1. Balloon end assembly; 2. Guidewire lumen; 3. Tube body assembly; 4. Outer tube; 5. Inner tube; 6. Isolator; 7. Outer tube sidewall; 8. Balloon body; 9. Tip end; 10. Contrast ring; 11. Catheter seat; 12. Second conical connector; 13. Inflation chamber; 14. Reagent channel; 15. First conical connector; 16. Intermediate tube; 17. Bevel; 18. Sealing assembly; 19. Tapered groove. Detailed Implementation

[0012] The present invention will be further described below with reference to the accompanying drawings and specific embodiments, so that those skilled in the art can better understand and implement the present invention. However, the embodiments are not intended to limit the present invention. Example

[0013] Reference Figure 1-4 As shown, a balloon catheter of this utility model includes: The outer tube 4 and outer tube 5 are fixedly equipped with a balloon end assembly 1 at their front ends, and an inner tube 5 is coaxially sleeved inside the outer tube 4. The outer tube 4 and inner tube 5 enclose an annular space, and two isolators 6 are arranged axially between them, precisely dividing the annular space into an inflation chamber 13 and a reagent channel 14. This multi-channel design gives the tube body 3 multiple functions to meet the needs of different treatment operations. The guidewire lumen 2 runs through the entire tube body 3, providing a path for the movement of the guidewire. The proximal end of the tube body 3 is fixedly fitted with a catheter seat 11, which has an internal channel. Its two ends are connected to the second tapered connector 12 and the reagent channel 14, respectively, playing an important role in operations such as guidewire retraction. At the same time, the tube body mechanism also has a tapered groove for fitting with the inclined surface 17 of the sealing assembly 18.

[0014] The injection mechanism includes first conical connectors 15 located on both sides of the tube body 3, with each end of the first conical connector 15 connected to a capsule 8. The capsule 8 covers the periphery of the outer wall of the tube body 3. The tube body 3 has a first through hole, with both ends connected to the capsule 8 and the inflation chamber 13, respectively, for controlling the inflation and deflation of the capsule 8. In addition, the tube body 3 also has a second through hole 15, consisting of at least two sets of porous mechanisms, respectively located on both sides of the capsule 8, with a pore size of 20µm-50µm, allowing for precise control of the flow of liquid or gas within the catheter. Both the first conical connector 15 and the second conical connector 12 have interfaces 3. The interface 3 of the first conical connector 15 is connected to an inflation / deflation device, and the interface 3 of the second conical connector 12 is connected to a contrast agent injection device or a drug injection device.

[0015] When using this balloon dilation catheter, the guidewire 4 passes through the guidewire lumen 2, and the tip end 9 limits the guidewire, supporting the balloon catheter's deep insertion into the blood vessel. Upon reaching the stenotic site, the balloon body 8 is inflated using the inflation / aspiration device connected to the first tapered connector 15, causing it to expand and open the blood vessel. At this time, the sealing assembly 19 is pushed to the point where the guidewire and guidewire lumen 2 meet, forming a seal in the inflation chamber 13 and maintaining the balloon body 8's inflated state to reshape the blood vessel. Simultaneously, contrast agent or drug can be released into the blood vessel through the reagent channel 14 and the second through-hole 15 via the contrast agent injection device or drug injection device connected to the second tapered connector 12. Because the reagent channel 14 opening is close to the edge of the balloon body 8, the edge of the balloon body 8 and the inner wall of the blood vessel form a receiving space, facilitating the release and positioning of drugs or contrast agents. During the procedure, the guidewire is pulled back while holding the catheter hub 11. Because the force on the guidewire is located within the catheter hub 11, it is offset by the supporting force of the catheter hub 11, preventing the catheter body 3 from being pulled back from the lesion. After pulling the guidewire back, inflation can continue, allowing for multiple consecutive vascular repairs or angiography. The capsule 8 is a compliant capsule with a drug-eluting coating on its outer surface. It releases medication upon expansion, improving the therapeutic effect.

[0016] See Figure 1 , Figure 4 As shown, the reagent channel 14 passes through the side wall of the outer tube 7 at its distal end, and the proximal end of the reagent channel 14 is connected to the second conical connector 2. The reagent channel 14 can release the contrast agent or drug into the blood vessel. At the same time, since the opening of the reagent channel 14 is close to the edge of the balloon 9, and the edge of the balloon 9 and the inner wall of the blood vessel form a accommodating space, the drug or contrast agent can be easily released into the accommodating space, reducing the release resistance. At the same time, the flow is restricted in the accommodating space, which is conducive to the absorption of the drug or the positioning of the contrast agent in this area.

[0017] The balloon 9 covers the periphery of the distal end of the tube 3. The tube 3 has a first through hole, the two ends of which are connected to the balloon 9 and the inflation chamber 13, respectively. The balloon 9 is usually inflatable or expandable and is used to expand or fill when needed. The tube 3 has a first through hole, the two ends of which are connected to the balloon 9 and the inflation chamber 13, respectively. When needed, such as for vasodilation or channel clearing, the inflation and deflation of the balloon 9, as well as the flow of liquid or gas in the inflation chamber 13, are controlled through the first through hole.

[0018] Through a multi-channel design and collaborative operation of various mechanisms, this system integrates multiple functions such as balloon inflation, contrast agent injection, and drug delivery to meet the needs of different medical scenarios and patient pathologies. It can be used continuously without repeated vascular intervention, reducing vascular damage and improving treatment efficiency. The compliant design of the balloon body 8 and the drug coating, combined with precise drug or contrast agent release, effectively enhance treatment outcomes.

[0019] The guidewire lumen 2 and outer tube 4 of the tube body 3 are made of polymer materials with good flexibility and biocompatibility, ensuring the safety and reliability of intravascular operations. The guidewire 4 is made of high-strength alloy material to ensure its strength and toughness. The sealing assembly 19 is made of rubber material with good sealing performance and elasticity. During assembly, each component is installed strictly according to the design requirements to ensure that the connections of each mechanism are tight and the functions are normal. For example, the position of the isolator 6 in the annular space is precisely controlled to ensure the dimensional accuracy and separation effect of the inflation chamber 13 and reagent channel 14; the intermediate tube 16 fits well with the guidewire lumen 2, etc. In clinical use, medical staff follow the operating procedures, first passing the guidewire through the guidewire lumen 2, guiding the balloon catheter into the blood vessel, and then performing balloon inflation, sealing assembly operation, and contrast agent or drug administration according to the degree of vascular stenosis.

[0020] The new balloon catheter is made of medical-grade polyurethane material, which has good flexibility and biocompatibility. The outer diameter of the catheter is designed to be 2.5 mm, and the length is available in three specifications: 120 cm, 150 cm and 180 cm, depending on different clinical needs.

[0021] This balloon catheter features three independent channels. The first channel is the balloon inflation channel, with an inner diameter of 0.5 mm, extending from the proximal end of the catheter into the balloon. A standard Luer tapered connector is attached proximally for easy connection to external inflation devices. The second channel is the guidewire lumen, with an inner diameter of 0.8 mm. This channel utilizes a special inner wall coating technology using polytetrafluoroethylene (PTFE) to reduce friction during guidewire passage. An adjustable hemostatic valve is located proximally at the guidewire lumen to prevent backflow and maintain a good seal when adjusting the guidewire position. The third channel is the contrast agent / drug channel, with an inner diameter of 1 mm. This channel is separated from the guidewire lumen by a 0.1 mm thick medical-grade polyethylene insulating layer, ensuring that the guidewire does not interfere with the delivery of contrast agent or medication during passage. A Luer tapered connector is also attached proximally to the contrast agent / drug channel for connecting a contrast agent injector or drug infusion device.

[0022] The balloon, located at the distal end of the catheter, is made of ultra-thin, high-strength polyethylene terephthalate (PET) material. The balloon has a diameter of 2mm when uninflated and can expand to a maximum diameter of 4mm, with a length of 20mm. The balloon is tightly connected to the catheter body via a heat-sealing process to ensure a tight seal during inflation.

[0023] In some embodiments, a radiopaque ring 10 is fitted onto the end of the guidewire 4 and / or the side of the tube 3 near the proximal end of the balloon 9 to facilitate radiopaque observation.

[0024] Before the procedure begins, the doctor inserts a guidewire through the guidewire lumen into the balloon catheter until it reaches the distal end. Simultaneously, the doctor checks the balloon inflation channel and contrast agent / drug channel for patency, ensuring there are no blockages or leaks. The balloon catheter is then connected to the appropriate inflation device, contrast agent injector, or drug infusion device and adjusted accordingly.

[0025] Guided by medical imaging equipment (such as an angiography machine), doctors use percutaneous puncture techniques to slowly insert a balloon catheter with a guidewire into a blood vessel through a puncture site in the femoral or radial artery. Guided by the guidewire, the doctor monitors the position of the balloon catheter in real time using medical imaging, gradually advancing it to the narrowed area of ​​the blood vessel. During advancement, the doctor can inject a small amount of contrast agent through the contrast agent / drug channel as needed to more clearly observe the course of the blood vessel and the extent of stenosis, ensuring the balloon catheter accurately reaches the target location.

[0026] Once the balloon catheter reaches the narrowed area, the doctor slowly injects sterile saline into the balloon through the inflation device connected to the balloon's inflation channel, causing the balloon to gradually inflate. During inflation, the doctor closely monitors the balloon's expansion and the effectiveness of the blood vessel dilation using medical imaging until the narrowed area is sufficiently dilated to achieve the desired lumen diameter. Then, the doctor guides the stent through a guidewire to the dilated blood vessel and releases it, completing the stent implantation procedure.

[0027] After stent implantation, the doctor inflates the balloon again through the balloon inflation channel to perform post-inflation, ensuring a tight fit between the stent and the vessel wall. After inflation, the gas or fluid inside the balloon is aspirated, causing it to deflate. Finally, the doctor carefully withdraws the balloon catheter and guidewire. During withdrawal, contrast agent / drug administration may be repeated through the contrast agent / drug channel as needed to monitor the stent's position and vessel patency. Post-operatively, the patient receives routine care and observation to prevent complications.

[0028] This multi-channel, independently separated design successfully solves the problem that existing balloon catheters cannot simultaneously achieve guidewire passage and contrast agent / drug delivery. During the procedure, the surgeon can simultaneously inject contrast agent or medication through the contrast agent / drug channels while the guidewire guides the balloon catheter to the designated location, greatly improving the convenience and precision of the surgical procedure.

[0029] The balloon is made of ultra-thin, high-strength PET material, which ensures effective dilation of narrowed blood vessels while minimizing damage to the vessel wall. The PTFE coating and independently compartmentalized design of the guidewire lumen reduce friction during guidewire passage, improves the smoothness of guidewire operation, and reduces the risk of guidewire jamming or entanglement within the catheter.

[0030] Although the new balloon catheter is relatively complex in its structural design, its production cost has not increased significantly due to the use of mature medical materials and manufacturing processes. Compared with existing balloon catheters, the new balloon catheter can improve surgical efficiency, reduce operation time and the occurrence of complications, thereby reducing overall medical costs and demonstrating good cost-effectiveness.

[0031] Obviously, the above embodiments are merely examples for clear illustration and are not intended to limit the implementation. Those skilled in the art will recognize that other variations or modifications can be made based on the above description. It is neither necessary nor possible to exhaustively list all possible implementations. However, obvious variations or modifications derived therefrom are still within the protection scope of this invention.

Claims

1. A balloon dilation catheter, characterized in that, include: The outer tube has a balloon end assembly fixedly installed at its front end, and an inner tube coaxially sleeved inside the outer tube. The outer and inner tubes enclose an annular space, and two axially spaced isolators precisely divide the annular space into an inflation chamber and a reagent channel. The guidewire lumen runs through the entire tube body, providing a path for the guidewire's movement. A catheter seat is fixedly sleeved at the proximal end of the tube body, and the catheter seat has an internal channel, with its two ends communicating with the second conical connector and the reagent channel, respectively. The guidewire moves through the guidewire lumen, and the shape of the sealing assembly matches the cross-sectional shape of the connection between the guidewire lumen and the inflation chamber. It can move within the guidewire lumen to the inflation chamber inlet under the drive of the guidewire, and movably seal between the guidewire lumen and the inflation chamber.

2. The balloon dilation catheter according to claim 1, characterized in that: The tube body includes a guidewire cavity tube and an outer tube coaxially sleeved together. An annular space is formed between the outer tube and the guidewire cavity tube. Two isolation elements are arranged axially between the guidewire cavity tube and the outer tube, dividing the annular space into an inflation chamber and a reagent channel.

3. The balloon dilation catheter according to claim 2, characterized in that: The reagent channel penetrates the side wall of the outer tube at its distal end; the proximal end of the reagent channel is connected to the second conical connector, realizing effective connection between the channels.

4. A balloon dilation catheter according to claim 3, characterized in that: Both the first and second conical connectors are equipped with interfaces; the interface of the first conical connector is used to connect an external inflation / deflation device to realize the inflation and deflation operations of the balloon; the interface of the second conical connector is used to connect an external contrast agent injection device or a drug injection device to meet the needs of clinical contrast imaging and drug delivery.

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