A multi-stage adjustable pulmonary vascular interventional balloon catheter

Abstract

The application provides a multi-stage adjustable pulmonary vascular intervention balloon catheter and belongs to the field of medical devices. The catheter is fixedly connected with a tube main body at one end, and the tube main body is fixedly connected with a pressure charging cavity, a guide wire cavity and a pressure relief cavity at the end away from the catheter, respectively. The pressure charging cavity, the guide wire cavity and the pressure relief cavity are in communication with the tube main body. The catheter is fixedly connected with a soft head at one end, and the pressure charging device is arranged at the end of the catheter close to the soft head. The application can trigger the opening of the corresponding valves of the inner, middle and outer three layers of balloons in sequence by means of precise control of the pressure charging pressure, realize the grading expansion effect of the precise shaping of the outer layer of balloons at 6 atm under the pre-expansion of the inner layer of balloons at 2 atm and the superimposed expansion of the middle layer of balloons at 4 atm, avoid the risk of overpressure by matching the spring safety valve opened at 8 atm in the pressure relief channel, enable the balloon to retract quickly and the valve to close automatically by negative pressure suction, reduce the risk of guide wire displacement, shorten the operation time and reduce the radiation exposure of patients.

Description

Technical Field

[0001] This invention relates to the field of medical devices, and more specifically, to a multi-level adjustable pulmonary vascular intervention balloon catheter. Background Technology

[0002] Pulmonary vascular interventional therapy is commonly used to treat conditions such as pulmonary artery stenosis and chronic thromboembolic pulmonary hypertension. Balloon angioplasty is a key technique in this treatment. Pulmonary artery stenosis, for example, causes the passage between the right ventricle and the pulmonary artery to narrow due to congenital malformations, resulting in symptoms such as chest tightness and shortness of breath. Chronic thromboembolic pulmonary hypertension is caused by the organization of pulmonary thrombi and vascular remodeling, leading to a continuous increase in pulmonary artery pressure and eventually causing right heart failure. Traditional treatment uses a single balloon stepwise dilation method. The doctor first uses a small balloon with a diameter of 2mm to pre-dilate the lesion, and then successively replaces it with larger balloons with diameters of 4mm and 6mm to gradually complete the treatment, in order to improve the vascular stenosis and restore normal blood flow to the lungs.

[0003] In traditional single-balloon stepwise dilation techniques for pulmonary vascular intervention, each change of balloon diameter (e.g., from 2mm to 4mm, then 6mm) necessitates guidewire repositioning, a process that takes an average of 15-20 minutes each time. This significantly prolongs the overall procedure time, increases the operator's workload, and the repeated guidewire adjustments increase the risk of displacement, potentially leading to surgical positioning errors and target vessel damage. Furthermore, multiple procedures extend the patient's exposure time under fluoroscopy, increasing radiation dose. The repeated instrument changes and guidewire adjustments also complicate the procedure and reduce treatment efficiency. To address these technical issues, existing technologies offer solutions such as patent publications CN219579689U and CN218793518U, which provide variable-diameter balloons to reduce the number of changes. However, balloon dilation still requires manual switching and may still necessitate multiple guidewire adjustments, resulting in instrument changes and complex procedures. Doctors need to repeatedly operate the pressurization channel switch or adjust the control components during the operation, which not only increases the number of manual operation steps, but also easily leads to delayed dilation timing or inaccurate pressure control due to deviation in the operation rhythm, resulting in over-dilation that damages the vascular endothelium or under-dilation that fails to achieve the treatment effect. Summary of the Invention

[0004] To address the problem that existing technologies still require manual switching of balloon dilation states, and that doctors need to repeatedly operate the inflation channel switch or adjust the control components during the procedure, the purpose of this invention is to provide a multi-level adjustable pulmonary vascular interventional balloon catheter.

[0005] To solve the above problems, the present invention adopts the following technical solution:

[0006] A multi-level adjustable pulmonary vascular interventional balloon catheter includes a catheter, an inflation device, and a pressure-linked contrast enhancement mechanism. One end of the catheter is fixedly connected to a main body. An inflation chamber, a guidewire chamber, and a depressurization chamber are fixedly connected to the end of the main body away from the catheter, respectively. These chambers communicate with the main body. A flexible tip is fixedly connected to one end of the catheter. The inflation device is located at the end of the catheter near the flexible tip, and the pressure-linked contrast enhancement mechanism is located at the end of the catheter away from the flexible tip. The inflation device includes an inner balloon, which is fixedly connected to the catheter. The inner balloon is covered with a middle balloon, and the middle balloon is covered with an outer balloon. Air vents are provided on the surfaces of the inner, middle, and outer balloons. A main sealing valve is rotatably connected to the surface of each air vent. A secondary sealing valve is rotatably connected to the end of each air vent near the main sealing valve. A sealing strip is fixedly connected to the upper surface of the secondary sealing valve. Four silicon nitride springs are symmetrically arranged, and the ends of the silicon nitride springs furthest from the air vents are fixedly connected to the main sealing valve and the secondary sealing valve, respectively.

[0007] The movement of the stop plate is driven by the pressure difference between the air pressure inside the inflation chamber and the external atmospheric pressure. The stop plate is fixed to one end of the slider on the inner wall of the inflation chamber. Under normal conditions, the tension of the rubber band keeps the stop plate in its initial position. When the inflation chamber inflates the balloon, the air pressure inside the chamber gradually becomes higher than the external atmospheric pressure, forming a pressure difference. When the pressure difference increases to a level sufficient to overcome the tension of the rubber band, the air pressure will push the stop plate to move away from the inflation device, thereby driving the slider and the ring fixed to the slider to move synchronously. Finally, the card on the ring and the strap rod cooperate to issue a prompt. The whole process does not rely on any additional parts. It only uses the natural air pressure difference inside and outside the inflation chamber after inflation, combined with the tension of the rubber band, to achieve the controllable movement of the stop plate.

[0008] Optionally, the surfaces of the inner balloon and the middle balloon are fixedly connected with protrusions, and there are multiple protrusions arranged in a circumferential array along the inner balloon and the middle balloon.

[0009] Optionally, the catheter has an exchange hole 15cm away from the soft tip, the total length of the catheter is 120cm, and the catheter is made of polyurethane composite material.

[0010] Optionally, the sealing valve opening pressure thresholds on the surfaces of the inner balloon, middle balloon, and outer balloon are different: the sealing valve opening pressure threshold of the inner balloon is 2±0.3 atm, the sealing valve opening pressure threshold of the middle balloon is 4±0.3 atm, and the sealing valve opening pressure threshold of the outer balloon is 6±0.3 atm.

[0011] First, the opening pressure thresholds of the sealing valves on the inner, middle, and outer balloon surfaces, including the main and secondary sealing valves, are clearly distinguished: 2±0.3 atm for the inner balloon, 4±0.3 atm for the middle balloon, and 6±0.3 atm for the outer balloon. During inflation, the air pressure is gradually increased through the inflation chamber. In the low-pressure stage (2±0.3 atm), only the inner balloon valve is opened by the air pressure; the middle and outer balloon valves remain closed due to the elastic support of the silicon nitride spring plates, as they have not reached the threshold. When the air pressure rises to 4±0.3 atm, the middle balloon valve opens against the elastic force of its own spring plate, while the outer balloon remains closed. The pressure continues to rise to 6±0.3 atm before the outer balloon valve opens, achieving graded expansion from the inside out. At the same time, when there is no air pressure or the air pressure drops, the silicon nitride spring plate will rebound and squeeze the main and secondary sealing valves to close. The sealing strip on the secondary sealing valve further enhances the sealing performance, preventing the backflow of gas inside the balloon and avoiding the problem of crossflow without additional structures.

[0012] Optionally, the inner wall of the soft tip is provided with an marking device, the marking device including a slider, the slider being slidably connected to the soft tip, a stop plate being fixedly connected to one end of the slider, the stop plate being located in the inner wall of the soft tip, a ring being sleeved on the surface of the soft tip, the ring being fixedly connected to the slider, a baffle being fixedly connected to the outer surface of the soft tip, a rubber band being fixedly connected to the lower surface of the baffle, the end of the rubber band away from the baffle being fixedly connected to the ring, there are three rubber bands, the three rubber bands are arranged in a circumferential array along the outer surface of the soft tip, and a bundle rod being fixedly connected to one end of the soft tip, there are three bundle rods.

[0013] Optionally, a rotating rod is fixedly connected to one end of the ring near the bundle rod, a card is rotatably connected to the surface of the rotating rod, an iron rod is fixedly connected to one end of the ring near the card, the iron rod is located on the lower surface of the card, and a torsion spring is sleeved on the surface of the rotating rod, with the two ends of the torsion spring fixedly connected to the card and the ring respectively.

[0014] Optionally, the inner wall of the pressure relief chamber is provided with a protective device, the protective device including a hollow tube, the hollow tube being fixed in the inner wall of the pressure relief chamber, a first partition being fixedly connected to the inner wall of the hollow tube, a second partition being fixedly connected to the end of the hollow tube near the first partition, through holes being opened on the surfaces of the first partition and the second partition, a frame being slidably connected to the through holes on the surfaces of the first partition and the second partition, a first cylinder and a second cylinder being fixedly connected to the surface of the frame, and air outlets being opened on the surfaces of the first partition and the second partition, the length of the first cylinder being shorter than the second cylinder.

[0015] The pressure relief is achieved through the difference in the elasticity of the pressure springs. The first and second partitions divide the hollow tube into different chambers. Both the first and second cylinders are fixed to the frame, and the frame is connected to the pressure springs. During pressure relief, the gas first enters the chamber of the hollow tube closest to the first partition. When the gas pressure overcomes the elasticity of the pressure spring corresponding to the first cylinder, the first cylinder is pushed open, and the gas enters the intermediate chamber through the outlet of the first partition. At this time, the gas pressure in the intermediate chamber needs to be further increased until it can overcome the elasticity of the pressure spring corresponding to the second cylinder in order to push open the second cylinder and complete the final pressure relief through the outlet of the second partition. Since the elasticity of the pressure springs in this case can be designed to adapt to the needs of different pressure relief stages, a graded effect is naturally formed, in which the first cylinder is pushed open by the small elasticity for slow relief, and then the second cylinder is pushed open by the large elasticity for fast relief.

[0016] Optionally, a bracket is fixedly connected to one side of the hollow tube, a pressure spring is fixedly connected to one end of the bracket, and the end of the pressure spring away from the bracket is fixedly connected to the frame.

[0017] Optionally, the pressure-linked imaging enhancement mechanism includes a linkage push rod, a wedge-shaped transmission block, an imaging marker slide, an elastic reset component, an enhanced imaging ring, and a sealing sleeve. One end of the linkage push rod is fixed to the inner wall of the ring. A sealing sleeve is fitted at the penetration point between the linkage push rod and the wall of the pressurization chamber. Both ends of the sealing sleeve are fixed to the outer and inner walls of the pressurization chamber with medical adhesive. The other end of the linkage push rod is threaded to the flat end of the wedge-shaped transmission block. The inclined surface of the wedge-shaped transmission block fits against the end face of the imaging marker slide. The imaging marker slide has a semi-annular structure and is detachably connected to the outer wall of the catheter through an elastic buckle on the inner wall.

[0018] Optionally, the enhanced imaging rings are respectively embedded in the grooves of the outer wall of the imaging mark slide, the enhanced imaging rings and the imaging mark slides are interference fit, the elastic reset member is sleeved on the outer wall of the conduit, the two ends of the elastic reset member abut against the side of the imaging mark slide and the fixing retaining ring on the conduit respectively, and the pressure chamber wall is provided with a through hole corresponding to the position of the linkage push rod.

[0019] The usage method of the above-mentioned multi-level adjustable pulmonary vascular interventional balloon catheter is as follows:

[0020] S1. Preoperative Preparation: Inspect the integrity of all components of the multi-stage adjustable pulmonary vascular interventional balloon catheter, ensuring the catheter's outer diameter is 5Fr, total length is 120cm, made of polyurethane composite material without damage, guidewire lumen diameter is 0.035 inches, an exchange port with a stainless steel reinforcing ring is located 15cm from the tip, the inflation chamber inner diameter is 0.5mm, the connection of the three-layer balloon is unobstructed, the pressure relief channel has an embedded spring-loaded safety valve with an opening pressure of 8atm, the three-layer nested balloon has an inner diameter of 2mm, made of nylon-polyurethane composite membrane with a burst pressure of 2atm, a middle diameter of 4mm, made of semi-compliant polyamide with a burst pressure of 4atm, and an outer diameter of 6mm, made of non-compliant PET (polyethylene terephthalate) with a burst pressure of 6atm without leakage, the inner valve opening pressure is 2±0.3atm, the middle valve opening pressure is 4±0.3atm, and the outer valve opening pressure is 6±0.3atm, all are normal, and the balloon interlayer ePTFE (expanded) is in good condition. The polytetrafluoroethylene (ePTFE) isolation layer is 35-40μm thick with a dielectric constant of 2.1 and has a 100μm diameter bump array with a 1mm spacing and no peeling. The triple gold tungsten alloy imaging markers are 99.99% pure with a 5mm spacing and are clear. At the same time, prepare the appropriate guidewire, inflation equipment, and DSA (Digital Subtraction Angiography) imaging equipment. Connect the inflation equipment to the inflation chamber and perform a sealing test to ensure that there is no leakage in the gas path.

[0021] S2. Guidewire Positioning: Select an appropriate guidewire and slowly insert it through the exchange port 15cm from the tip of the catheter. With the assistance of DSA imaging equipment, guide the tip of the guidewire to the target vessel corresponding to the pulmonary vascular stenosis. Then, slowly push the catheter body along the guidewire. By observing the triple gold tungsten alloy imaging marks on the catheter, adjust the catheter position so that the three-layer nested balloon is accurately aligned with the lesion. After positioning, fix the guidewire position to prevent the guidewire from shifting during subsequent operations.

[0022] S3. Staged Dilation: Start the inflation device and slowly inflate the catheter inflation chamber. The initial inflation rate is controlled at 0.2-0.5 atm / s. When the inflation pressure reaches 2±0.3 atm, the sealing valve corresponding to the inner balloon opens under the action of air pressure, while the outer and middle valves remain closed. The inner balloon begins to inflate and expand. Maintain this pressure for 30-60 seconds to pre-dilate the narrowed vessel inlet to initially widen the vascular passage. Continue slow inflation. When the pressure rises to 4±0.3 atm, the sealing valve corresponding to the middle balloon opens, and the middle balloon overlaps the inner balloon. The outer balloon expands and expands, utilizing the properties of the middle layer of semi-compliant polyamide material to better adapt to the vascular morphology. This pressure is maintained for 45-90 seconds to further expand the blood vessel, continuously inflating to 6±0.3 atm. The corresponding sealing valve of the outer balloon opens, and the outer non-compliant PET balloon fully inflates, ensuring precise shaping of the narrowed area of ​​the blood vessel. This pressure is maintained for 60-120 seconds. During this process, if the pressure in the inflation chamber exceeds 8 atm, the spring-loaded safety valve in the pressure relief channel automatically opens to release excess gas, preventing damage to the blood vessel or balloon due to excessive pressure.

[0023] S4. Pressure Relief and Retraction: After vasodilation is complete, turn off the pressure function of the pressure device and start the negative pressure aspiration device. The three-layer balloon is aspirated under negative pressure through the pressure chamber. The aspiration pressure is set to -0.8 atm. Under the action of negative pressure, the three-layer balloon gradually retracts. Aspiration lasts for 15-30 seconds to ensure that the balloon is completely retracted to its initial state. At the same time, the sealing valves corresponding to the three-layer balloon automatically close under the elastic restoring force of the silicon nitride spring plate to prevent gas from entering or leaking in the absence of pressure.

[0024] S5. Instrument Removal: After confirming that the balloon has completely retracted, under the monitoring of DSA imaging equipment, slowly pull the guidewire until the tip of the guidewire exits the target blood vessel, then slowly remove the catheter body from the patient's body along the guidewire. Keep the movement smooth during the removal process to avoid scratching or damaging the blood vessel wall with the catheter or guidewire. After the instruments are removed, clean and disinfect the catheter, guidewire, and other instruments according to medical standards. If they need to be reused, further sterilization testing is required to ensure that they meet the usage standards.

[0025] Compared with the prior art, the technical solution provided by this invention has at least the following beneficial effects:

[0026] In the above scheme, by setting up a pressurization device, the corresponding valves of the inner, middle and outer balloons can be triggered sequentially by precisely controlling the pressurization pressure. This achieves a graded expansion effect, with the inner balloon pre-dilation at 2 atm, the middle balloon superposition expansion at 4 atm, and the outer balloon precise shaping at 6 atm. The spring-loaded safety valve that opens at 8 atm in the pressure relief channel can avoid the risk of overpressure. Negative pressure aspiration can make the balloon retract quickly and the valve close automatically. At the same time, the interlayer protrusion array prevents balloon adhesion. Ultimately, a single catheter can be inserted to complete three-stage dilation, which greatly reduces the number of instrument changes, reduces the risk of guidewire displacement, shortens the operation time, and reduces the patient's radiation exposure.

[0027] By setting up an indicator device that precisely links with the graded pressure thresholds of the inflation device, the opening status of the inner, middle, and outer balloons is fed back in real time via mechanical sound. This helps operators accurately control the inflation process without relying on additional monitoring equipment, reducing the risk of over-expansion damaging blood vessels or under-expansion failing to achieve the therapeutic effect due to pressure judgment errors. It also complements the overpressure relief function of the protection device. When the pressure approaches or exceeds the safety threshold, either the indicator device will remind the operator to stop inflation, or the protection device will automatically release pressure, providing double protection for surgical safety. Furthermore, combined with the single-catheter graded dilation advantage of the inflation device, it reduces instrument changes and operation steps, shortens surgical time, reduces the risk of patient radiation exposure, and improves the overall accuracy, safety, and efficiency of the surgery.

[0028] By setting up a protective device, a graded pressure relief structure is formed by the first and second cylinders of different lengths during pressure relief. This ensures that the gas needs to reach different pressures before it can push open the cylinders and be discharged in sequence. This reduces the impact damage to blood vessels or balloons caused by excessively rapid pressure relief. Furthermore, after the air pressure is removed, the pressure spring can drive the cylinder to automatically close the air outlet, preventing external impurities from entering or gas from flowing back. This ensures a smooth and safe pressure relief process, further improving the safety and stability of the entire surgical procedure.

[0029] By linking the push rods to create dual feedback—high-brightness visual cues from DSA and audible metallic impact—doctors can accurately control the graded expansion status of the inner, middle, and outer balloons in real time. This reduces over-expansion or under-expansion caused by pressure misjudgment, lowers the risk of vascular injury, and further improves the accuracy of graded expansion and surgical safety, while not affecting the airtightness and core functional compatibility of the original equipment. Attached Figure Description

[0030] The accompanying drawings, which are incorporated herein and form part of the specification, illustrate embodiments of the invention and, together with the specification, further serve to explain the principles of the invention and enable those skilled in the art to practice and use the invention.

[0031] Figure 1 This is a three-dimensional structural diagram of the present invention;

[0032] Figure 2 For the present invention Figure 1 A cross-sectional structural diagram of the pressurization device;

[0033] Figure 3 For the present invention Figure 2 Enlarged structural diagram at point A;

[0034] Figure 4 For the present invention Figure 1 A schematic diagram of the structure of the Chinese identification device;

[0035] Figure 5 For the present invention Figure 4 An enlarged structural diagram at point B;

[0036] Figure 6 For the present invention Figure 4 A partial structural diagram of the signage device;

[0037] Figure 7 For the present invention Figure 4 A cross-sectional structural diagram of the signage device;

[0038] Figure 8 This is a schematic diagram of the protective device of the present invention;

[0039] Figure 9 This is a schematic diagram of the pressure-linked imaging enhancement mechanism of the present invention.

[0040] [Figure Labels]

[0041] 1. Catheter; 2. Catheter body; 3. Inflation chamber; 4. Guidewire chamber; 5. Decompression chamber; 6. Flexible tip;

[0042] 7. Pressurization device; 71. Outer balloon; 72. Middle balloon; 73. Inner balloon; 74. Air vent; 75. Main sealing valve; 76. Silicon nitride spring plate; 77. Secondary sealing valve; 78. Sealing strip; 79. Protrusion; 710. Exchange hole;

[0043] 8. Identification device; 81. Ring; 82. Baffle; 83. Rubber band; 84. Bundle rod; 85. Card; 86. Iron rod; 87. Rotating rod; 88. Torsion spring; 89. Slider; 810. Stop plate;

[0044] 9. Protective device; 91. Hollow tube; 92. First partition; 93. Second partition; 94. First cylinder; 95. Second cylinder; 96. Compression spring; 97. Bracket; 98. Frame;

[0045] 10. Linkage push rod; 11. Wedge-shaped transmission block; 12. Developing mark slide; 13. Elastic reset component; 14. Reinforced developing ring; 15. Sealing sleeve.

[0046] As shown in the figure, specific structures and devices are marked in the figure to clearly illustrate the structure of the embodiments of the present invention. However, this is only for illustrative purposes and is not intended to limit the present invention to this specific structure, device and environment. Those skilled in the art can adjust or modify these devices and environments according to specific needs. Detailed Implementation

[0047] The present invention will now be described in detail with reference to the accompanying drawings and specific embodiments. It should also be noted that, to make the embodiments more comprehensive, the following embodiments are the best and preferred embodiments, and those skilled in the art can use other alternative methods to implement some well-known technologies; moreover, the accompanying drawings are only for more specific description of the embodiments and are not intended to specifically limit the present invention.

[0048] It should be noted that the use of terms such as "an embodiment," "an embodiment," "an exemplary embodiment," and "some embodiments" in the specification indicates that the described embodiment may include a specific feature, structure, or characteristic, but not every embodiment necessarily includes that specific feature, structure, or characteristic. Furthermore, when describing a specific feature, structure, or characteristic in conjunction with embodiments, the implementation of such feature, structure, or characteristic in conjunction with other embodiments, whether or not explicitly described, should be within the knowledge of those skilled in the art.

[0049] Generally, terms can be understood at least partly from their use in context. For example, depending at least partly on the context, the term "one or more" as used herein can be used to describe any feature, structure, or characteristic in a singular sense, or a combination of features, structures, or characteristics in a plural sense. Additionally, the term "based on" can be understood not necessarily to convey an exclusive set of factors, but rather, alternatively, depending at least partly on the context, to allow for the presence of other factors that are not necessarily explicitly described.

[0050] It is understood that the meanings of “on”, “above”, and “above” in this invention should be interpreted in the broadest manner, such that “on” means not only “directly on” something, but also includes the meaning of being “on” something with an intervening feature or layer, and that “above” or “above” means not only “on” something, but also includes the meaning of being “on” something without an intervening feature or layer.

[0051] Furthermore, spatially related terms such as “below,” “under,” “lower,” “above,” and “upper” are used herein for convenience to describe the relationship of one element or feature to one or more other elements or features, as illustrated in the accompanying drawings. Spatially related terms are intended to cover different orientations in the use or operation of the device other than those depicted in the accompanying drawings. The device may be oriented in other ways, and the spatially related descriptive terms used herein can be interpreted similarly.

[0052] like Figures 1 to 9 As shown, this embodiment of the invention provides a multi-level adjustable pulmonary vascular intervention balloon catheter 1, including a catheter 1, an inflation device 7, and a pressure-linked contrast enhancement mechanism. One end of the catheter 1 is fixedly connected to a tube body 2. The end of the tube body 2 away from the catheter 1 is respectively fixedly connected to an inflation chamber 3, a guidewire chamber 4, and a pressure relief chamber 5. The inflation chamber 3, guidewire chamber 4, and pressure relief chamber 5 are connected to the tube body 2. One end of the catheter 1 is fixedly connected to a flexible tip 6. The inflation device 7 is located at the end of the catheter 1 near the flexible tip 6.

[0053] like Figure 1 and Figure 3 As shown, the pressurization device 7 includes an inner balloon 73, which is fixedly connected to the conduit 1 and communicates with the conduit 1. A middle balloon 72 is fitted on the surface of the inner balloon 73, and an outer balloon 71 is fitted on the surface of the middle balloon 72. Air holes 74 are provided on the surfaces of the inner balloon 73, the middle balloon 72, and the outer balloon 71. A main sealing valve 75 is rotatably connected to the surface of the air hole 74. A secondary sealing valve 77 is rotatably connected to one end of the air hole 74 near the main sealing valve 75. A sealing strip 78 is fixedly connected to the upper surface of the secondary sealing valve 77. A silicon nitride spring plate 76 is fixedly connected to one end of the air hole 74. There are four silicon nitride spring plates 76, which are symmetrically arranged. The ends of the silicon nitride spring plates 76 away from the air holes 74 are fixedly connected to the main sealing valve 75 and the secondary sealing valve 77, respectively.

[0054] The inner balloon 73 and the middle balloon 72 are fixedly connected to the surfaces of protrusions 79. There are multiple protrusions 79, and the multiple protrusions 79 are arranged in a circumferential array along the inner balloon 73 and the middle balloon 72.

[0055] The catheter 1 has an exchange hole 710 located 15cm away from the soft tip 6. The total length of the catheter 1 is 120cm. The catheter 1 is made of polyurethane composite material.

[0056] The sealing valves on the surfaces of the inner balloon 73, the middle balloon 72, and the outer balloon 71 have different opening pressure thresholds. The sealing valve opening pressure threshold of the inner balloon 73 is 2±0.3 atm, the sealing valve opening pressure threshold of the middle balloon 72 is 4±0.3 atm, and the sealing valve opening pressure threshold of the outer balloon 71 is 6±0.3 atm.

[0057] This invention, by setting up a pressurization device 7, can sequentially trigger the opening of the corresponding valves of the inner, middle, and outer balloons by precisely controlling the pressurization pressure. This achieves a graded expansion effect, with the inner balloon pre-expanding at 2 atm, the middle balloon stacking expansion at 4 atm, and the outer balloon precisely forming at 6 atm. Combined with a spring-loaded safety valve that opens at 8 atm in the pressure relief channel, the risk of overpressure can be avoided. Negative pressure aspiration can cause the balloon to retract quickly and the valves to close automatically. At the same time, the interlayer protrusion array 79 prevents balloon adhesion. Ultimately, a single catheter 1 is inserted to complete three-stage expansion, which significantly reduces the number of instrument changes, reduces the risk of guidewire displacement, shortens the operation time, and reduces the patient's radiation exposure.

[0058] like Figure 4 and Figure 7 As shown, the inner wall of the soft tip 6 is provided with an marking device 8, which includes a slider 89. The slider 89 is slidably connected to the soft tip 6. One end of the slider 89 is fixedly connected to a stop plate 810, which is located in the inner wall of the soft tip 6. A ring 81 is sleeved on the surface of the soft tip 6 and is fixedly connected to the slider 89. A baffle 82 is fixedly connected to the outer surface of the soft tip 6. A rubber band 83 is fixedly connected to the lower surface of the baffle 82, and the end of the rubber band 83 away from the baffle 82 is fixedly connected to the ring 81.

[0059] There are three rubber bands 83, which are arranged in a circumferential array along the outer surface of the soft head 6. One end of the soft head 6 is fixedly connected to a tie rod 84, and there are three tie rods 84.

[0060] A rotating rod 87 is fixedly connected to one end of the ring 81 near the bundle rod 84. A card 85 is rotatably connected to the surface of the rotating rod 87. An iron rod 86 is fixedly connected to one end of the ring 81 near the card 85. The iron rod 86 is located on the lower surface of the card 85. A torsion spring 88 is sleeved on the surface of the rotating rod 87. The two ends of the torsion spring 88 are fixedly connected to the card 85 and the ring 81, respectively.

[0061] By setting up an indicator device 8, the present invention can generate a crisp metallic impact sound through mechanical linkage when the balloon is inflated to the pressure required for balloon expansion, such as 2 atm. This timely and clear reminder to the operator that the current pressure has reached the target threshold helps the operator to accurately control the inflation process, reduce the problem of over-expansion or under-expansion caused by inaccurate pressure judgment, and improve the accuracy and safety of surgical operation.

[0062] like Figure 8 and Figure 9 As shown, the inner wall of the pressure relief chamber 5 is provided with a protective device 9. The protective device 9 includes a hollow tube 91, which is fixed in the inner wall of the pressure relief chamber 5. A first partition 92 is fixedly connected to the inner wall of the hollow tube 91. A second partition 93 is fixedly connected to one end of the hollow tube 91 near the first partition 92. Through holes are opened on the surfaces of the first partition 92 and the second partition 93. A frame 98 is slidably connected to the through holes on the surfaces of the first partition 92 and the second partition 93. A first cylinder 94 and a second cylinder 95 are fixedly connected to the surface of the frame 98. An air outlet is opened on the surfaces of the first partition 92 and the second partition 93. The length of the first cylinder 94 is shorter than that of the second cylinder 95.

[0063] A bracket 97 is fixedly connected to one side of the hollow tube 91, and a pressure spring 96 is fixedly connected to one end of the bracket 97. The end of the pressure spring 96 away from the bracket 97 is fixedly connected to the frame 98.

[0064] The pressure-linked imaging enhancement mechanism includes a linkage push rod 10, a wedge-shaped transmission block 11, an imaging mark slide 12, an elastic reset component 13, an enhanced imaging ring 14, and a sealing sleeve 15. One end of the linkage push rod 10 is fixed to the inner wall of the ring 81. The sealing sleeve 15 is fitted at the penetration point between the linkage push rod 10 and the wall of the pressurization chamber 3. Both ends of the sealing sleeve 15 are fixed to the outer and inner walls of the pressurization chamber 3 with medical adhesive. The other end of the linkage push rod 10 is threaded to the flat end of the wedge-shaped transmission block 11. The inclined surface of the wedge-shaped transmission block 11 is in contact with the end face of the imaging mark slide 12. The imaging mark slide 12 has a semi-annular structure and is detachably connected to the outer wall of the catheter 1 through an elastic buckle on the inner wall.

[0065] The enhanced developing rings 14 are respectively embedded in the grooves on the outer wall of the developing mark slide 12. The enhanced developing rings 14 and the developing mark slide 12 are pressurized together. The elastic reset member 13 is sleeved on the outer wall of the conduit 1. The two ends of the elastic reset member 13 abut against the side of the developing mark slide 12 and the fixing retaining ring on the conduit 1, respectively. The wall of the pressurizing chamber 3 has a through hole corresponding to the position of the linkage push rod 10.

[0066] The usage method of the above-mentioned multi-level adjustable pulmonary vascular interventional balloon catheter is as follows:

[0067] S1. Preoperative preparation: Inspect the integrity of each component of the multi-stage adjustable pulmonary vascular interventional balloon catheter 1, ensuring that the catheter 1 has an outer diameter of 5Fr, a total length of 120cm, is made of polyurethane composite material without damage, the guidewire lumen 4 has a diameter of 0.035 inches, an exchange port 710 with a stainless steel reinforcing ring is located 15cm from the tip, the inflation chamber 3 has an inner diameter of 0.5mm, connecting the three-layer balloon, and the pressure relief channel has an embedded spring-loaded safety valve with an opening pressure of 8atm that is unobstructed. The inner layer of the three-layer nested balloon has a diameter of 2mm, is made of nylon-polyurethane composite membrane, and has a burst pressure of 2atm; the middle layer has a diameter of 4mm, is made of semi-compliant polyamide, and has a burst pressure of 4atm. m, outer layer diameter 6mm, material is non-compliant PET, burst pressure 6atm with no leakage, inner valve opening pressure 2±0.3atm, middle layer 4±0.3atm, outer layer 6±0.3atm, normal condition, interlayer ePTFE isolation layer thickness 35-40μm, dielectric constant 2.1, and bump 79 array diameter 100μm, spacing 1mm with no detachment, triple gold tungsten alloy imaging mark purity 99.99%, spacing 5mm clear, at the same time, prepare the matching guide wire, pressurization equipment and DSA imaging equipment, connect the pressurization equipment to the pressurization chamber 3 and perform a sealing test to ensure no gas leakage.

[0068] S2. Guidewire Positioning: Select a suitable guidewire and slowly insert it through the exchange port 710, 15cm from the tip of catheter 1. With the assistance of DSA imaging equipment, guide the tip of the guidewire to the target vessel corresponding to the pulmonary vascular stenosis. Then, slowly push the main body of catheter 1 along the guidewire. By observing the triple gold tungsten alloy imaging marks on catheter 1, adjust the position of catheter 1 so that the three-layer nested balloon is accurately aligned with the lesion site. After positioning, fix the position of the guidewire to prevent it from shifting during subsequent operations.

[0069] S3. Staged Dilation: Start the inflation device and slowly inflate the inflation chamber 3 of catheter 1. The initial inflation rate is controlled at 0.2-0.5 atm / s. When the inflation pressure reaches 2±0.3 atm, the sealing valve corresponding to the inner balloon 73 opens under air pressure, while the outer and middle valves remain closed. The inner balloon 73 begins to inflate and expand. Maintain this pressure for 30-60 seconds to pre-dilate the narrowed vessel entrance, initially widening the vascular passage. Continue slow inflation. When the pressure rises to 4±0.3 atm, the sealing valve corresponding to the middle balloon 72 opens, and the middle balloon 72 overlaps with the inner balloon. The outer balloon 73 expands and inflates, utilizing the properties of the middle layer of semi-compliant polyamide material to better adapt to the vascular morphology. This pressure is maintained for 45-90 seconds to further dilate the blood vessel, continuously inflating to 6±0.3 atm. The sealing valve corresponding to the outer balloon 71 opens, and the outer non-compliant PET balloon fully inflates, ensuring precise shaping of the narrowed area of ​​the blood vessel. This pressure is maintained for 60-120 seconds. During this process, if the pressure in the inflation chamber 3 exceeds 8 atm, the spring-loaded safety valve in the pressure relief channel automatically opens to release excess gas, preventing damage to the blood vessel or balloon due to excessive pressure.

[0070] S4. Pressure Relief and Retraction: After vasodilation is completed, turn off the pressure function of the pressure device and start the negative pressure suction device. The three-layer balloon is suctioned under negative pressure through the pressure chamber 3. The suction pressure is set to -0.8 atm. Under the action of negative pressure, the three-layer balloon gradually retracts. The suction lasts for 15-30 seconds to ensure that the balloon is completely retracted to its initial state. At the same time, the sealing valves corresponding to the three-layer balloon automatically close under the elastic restoring force of the silicon nitride spring plate 76 to prevent gas from entering or leaking in the absence of pressure.

[0071] S5. Instrument Removal: After confirming that the balloon has completely retracted, under the monitoring of DSA imaging equipment, slowly pull the guidewire first. After the tip of the guidewire exits the target blood vessel, slowly remove the main body of catheter 1 from the patient's body along the guidewire. Keep the movement smooth during the removal process to avoid scratching or damaging the blood vessel wall with catheter 1 or guidewire. After the instrument is removed, clean and disinfect catheter 1, guidewire and other instruments according to medical standards. If reuse is required, further sterilization testing is required to ensure that it meets the usage standards.

[0072] By adopting the above technical solution, the valves of the inner, middle, and outer balloons can be opened sequentially by precisely controlling the inflation pressure. This achieves a graded expansion effect, with the inner balloon pre-expanding at 2 atm, the middle balloon stacking expansion at 4 atm, and the outer balloon precisely formed at 6 atm. The spring-loaded safety valve that opens at 8 atm in the pressure relief channel can avoid the risk of overpressure. Negative pressure aspiration can make the balloon retract quickly and the valve close automatically. At the same time, the 79 array of interlayer protrusions prevents balloon adhesion. Ultimately, a single catheter can be inserted to complete three-stage dilation, which greatly reduces the number of instrument changes, reduces the risk of guidewire displacement, shortens the operation time, and reduces the patient's radiation exposure.

[0073] The working process of the technical solution provided by this invention is as follows:

[0074] By setting up the inflation device 7, during use, the guidewire is first positioned. The guidewire is inserted into the target vessel through the exchange port 710 on the catheter 1. The catheter 1 is advanced along the guidewire to the lesion site. Positioning is achieved through gold-tungsten alloy triple contrast markers under DSA. Then, the graded dilation stage begins. When the inflation reaches 2 atm, only the main sealing valve 75 and the secondary sealing valve 77 corresponding to the inner balloon 73 are opened by air pressure. The inner balloon 73 dilates to adapt to the pre-dilation requirements of the stenosis inlet. When the inflation reaches 4 atm, the main sealing valve 75 and the secondary sealing valve 77 corresponding to the middle balloon open. The middle balloon dilates in a superimposed manner, and its semi-compliant material can adapt to the vascular morphology. When the inflation reaches 6 atm, the outer balloon corresponding to... The main sealing valve 75 and the secondary sealing valve 77 open, and the outer balloon is fully inflated to ensure precise shaping. The pressure chamber 3 of catheter 1 connects to the three balloon layers. The pressure relief channel is embedded with a spring-loaded safety valve with an opening pressure of 8 atm to release gas in case of overpressure. Finally, the pressure relief and retraction stage is entered. The three balloon layers are fully retracted by negative pressure suction of -0.8 atm. At the same time, the three main sealing valves 75 and the secondary sealing valves 77 automatically close. They are reset and closed by the elastic compression of the silicon nitride spring plate 76. When there is no pressure, they fit tightly due to the elastic restoring force. Each balloon layer is provided with an array of protrusions 79 to prevent adhesion and maintain the uniformity of the gap. The whole process realizes three-stage dilation with a single catheter 1 insertion without the need to change instruments.

[0075] By setting up the protection device 9, when the pressure is released, the gas enters the hollow tube 91 and impacts the first cylinder 94 to open the air outlet and enter the gap between the first partition 92 and the second partition 93. Since the length of the first cylinder 94 is shorter than that of the second cylinder 95, the air pressure needs to be greater after the first cylinder 94 is pushed open in order to push the second cylinder 95 open again to discharge. When the air pressure disappears, the pressure spring 96 loses its restraint and squeezes the frame 98 to drive the first cylinder 94 and the second cylinder 95 to close the air outlet again.

[0076] By setting up the marking device 8 and the linkage push rod 10, in the initial state, the ring 81 of the marking device 8 is in the proximal initial position under the tension of the rubber band 83, the linkage push rod 10 is not subjected to axial thrust, the wedge-shaped transmission block 11 and the developing mark slide 12 are not squeezed, the developing mark slide 12 maintains the initial spacing under the support of the elastic reset member 13, the nano-reflective coating of the enhanced developing ring 14 is in a natural state, and the three equidistant marking points with normal brightness are presented under DSA. When the pressurizing device 7 performs graded pressurization, the air pressure of the soft head 6 gradually increases. When the pressure reaches the opening threshold of the balloon 73 inside the pressurizing device 7 (2±0.3 atm), the air pressure overcomes the tension of the rubber band 83 in the marking device 8, and pushes the resist plate 810 and the connected slide plate on the inner wall of the soft head 6. 89. The ring 81 moves, pushing the ring 81 to the far end and driving the linkage push rod 10 to move axially in sync. The wedge-shaped transmission block 11 moves with the push rod and its inclined surface presses the first developing mark slide 12, causing the slide to expand slightly radially along the guide tube 1 and compress the elastic reset member 13. The developing ring spacing remains in the initial state, but the radial expansion stretches the nano-reflective coating. The brightness of the first developing mark point under DSA is significantly enhanced. At the same time, the card 85 on the ring 81 of the marking device 8 moves with the ring 81 to abut against the first tie rod 84. The tie rod 84 presses the card 85 to tilt. After passing through the card 85, the torsion spring 88 drives the card 85 to reset and collide with the iron rod 86 to produce a metallic impact sound. The card 85 collides with the first tie rod 84 to produce the first metallic impact sound.

[0077] When the inflation continues to the middle balloon 72 opening threshold of 4±0.3 atm, the air pressure continues to rise, further pushing the stop plate 810, the slider 89, and the ring 81 to move further distally. The linkage push rod 10 drives the wedge-shaped transmission block 11 to squeeze the second imaging mark slide 12. The second imaging slide expands radially and its imaging ring reflectivity increases. The first slide remains in an enhanced state under the continuous action of the elastic reset member 13 and the wedge-shaped transmission block 11. The brightness of the two imaging mark points increases. At the same time, the card 85 of the marking device 8 collides with the second bundle rod 84, producing a second metallic impact sound, forming a double prompt. When the inflation reaches the outer balloon 71 opening threshold of 6±0.3 atm, the ring 81 moves to its maximum stroke, and the wedge-shaped transmission block 11 squeezes the third imaging mark slide. The three developing rings of seat 12 are in a highly reflective state, and under DSA, they appear as three equally spaced bright marking points. At the same time, the card 85 collides with the third bundle rod 84, producing a third metallic impact sound. After depressurization, the negative pressure suction causes the ring 81 to reset under the tension of the rubber band 83. The linkage push rod 10 drives the wedge-shaped transmission block 11 to return to the initial position. The developing marking slide 12 contracts under the elastic force of the elastic reset member 13, restoring the initial spacing and reflectivity, ready for the next use. The entire process is triggered by the graded pressure threshold of the pressurization device 7. When the pressurization pressure exceeds the opening pressure of the 8atm spring-type safety valve embedded in the pressure relief channel of the protection device 9, the protection device 9 automatically depressurizes. At this time, the marking device 8 no longer triggers the sound, forming a pressure linkage protection.

[0078] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A multi-level adjustable pulmonary vascular intervention balloon catheter, comprising a catheter, an inflation device, and a pressure-linked contrast enhancement mechanism, characterized in that, One end of the catheter is fixedly connected to the tube body, and the end of the tube body away from the catheter is fixedly connected to a pressurizing chamber, a guidewire chamber and a pressure relief chamber respectively. The pressurizing chamber, guidewire chamber and pressure relief chamber are connected to the tube body. One end of the catheter is fixedly connected to a flexible tip. The pressurizing device is located at the end of the catheter close to the flexible tip. The pressure-linked imaging enhancement mechanism is located at the end of the catheter away from the flexible tip. The pressurization device includes an inner balloon, which is fixedly connected to a catheter and communicates with the catheter. A middle balloon is fitted over the surface of the inner balloon, and an outer balloon is fitted over the surface of the middle balloon. Air holes are provided on the surfaces of the inner, middle, and outer balloons. A main sealing valve is rotatably connected to the surface of each air hole. A secondary sealing valve is rotatably connected to the end of each air hole near the main sealing valve. A sealing strip is fixedly connected to the upper surface of the secondary sealing valve. A silicon nitride spring is fixedly connected to one end of each air hole. The end of the silicon nitride spring away from the air hole is fixedly connected to both the main and secondary sealing valves. The opening pressure thresholds of the sealing valves on the surfaces of the inner, middle, and outer balloons are different. By setting up a pressurization device, the corresponding valves of the inner balloon, middle balloon, and outer balloon can be triggered sequentially by controlling the pressurization pressure, so as to achieve pre-expansion of the inner balloon at 2 atm, superimposed expansion of the middle balloon at 4 atm, and graded expansion of the outer balloon at 6 atm. A spring-loaded safety valve is installed in the pressure relief channel, and negative pressure suction can make the balloon retract quickly and the valve close automatically.

2. The multi-stage adjustable pulmonary vascular intervention balloon catheter according to claim 1, characterized in that, The inner and middle balloons are fixedly connected to protrusions, which are arranged in a circumferential array along the inner and middle balloons.

3. The multi-stage adjustable pulmonary vascular intervention balloon catheter according to claim 2, characterized in that, The conduit has an exchange port and is made of polyurethane composite material.

4. The multi-stage adjustable pulmonary vascular interventional balloon catheter according to claim 1, characterized in that, The inner wall of the soft tip is provided with an marking device, which includes a slider that is slidably connected to the soft tip. One end of the slider is fixedly connected to a stop plate, which is located in the inner wall of the soft tip. A ring is sleeved on the surface of the soft tip and is fixedly connected to the slider. A baffle is fixedly connected to the outer surface of the soft tip. A rubber band is fixedly connected to the lower surface of the baffle. The end of the rubber band away from the baffle is fixedly connected to the ring. The rubber bands are arranged in a circumferential array along the outer surface of the soft tip. One end of the soft tip is fixedly connected to a bundle rod.

5. The multi-stage adjustable pulmonary vascular intervention balloon catheter according to claim 4, characterized in that, A rotating rod is fixedly connected to one end of the ring near the bundle rod. A card is rotatably connected to the surface of the rotating rod. An iron rod is fixedly connected to one end of the ring near the card. The iron rod is located on the lower surface of the card. A torsion spring is sleeved on the surface of the rotating rod. The two ends of the torsion spring are fixedly connected to the card and the ring, respectively.

6. The multi-stage adjustable pulmonary vascular intervention balloon catheter according to claim 1, characterized in that, The inner wall of the pressure relief chamber is provided with a protective device, which includes a hollow tube fixed in the inner wall of the pressure relief chamber. A first partition is fixedly connected to the inner wall of the hollow tube, and a second partition is fixedly connected to the end of the hollow tube near the first partition. Through holes are opened on the surfaces of the first and second partitions. A frame is slidably connected to the through holes on the surfaces of the first and second partitions. A first cylinder and a second cylinder are fixedly connected to the surface of the frame. Air outlets are opened on the surfaces of the first and second partitions. The length of the first cylinder is shorter than that of the second cylinder.

7. The multi-stage adjustable pulmonary vascular intervention balloon catheter according to claim 6, characterized in that, A bracket is fixedly connected to one side of the hollow tube, and a pressure spring is fixedly connected to one end of the bracket. The end of the pressure spring away from the bracket is fixedly connected to the frame.

8. The multi-stage adjustable pulmonary vascular intervention balloon catheter according to claim 1, characterized in that, The pressure-linked imaging enhancement mechanism includes a linkage push rod, a wedge-shaped transmission block, an imaging marker slide, an elastic reset component, an enhanced imaging ring, and a sealing sleeve. One end of the linkage push rod is fixed to the inner wall of the ring. A sealing sleeve is fitted at the penetration point between the linkage push rod and the wall of the pressure chamber. Both ends of the sealing sleeve are fixed to the outer and inner walls of the pressure chamber with medical adhesive. The other end of the linkage push rod is threaded to the flat end of the wedge-shaped transmission block. The inclined surface of the wedge-shaped transmission block fits against the end face of the imaging marker slide. The imaging marker slide has a semi-annular structure and is detachably connected to the outer wall of the catheter through an elastic buckle on the inner wall.

9. The multi-stage adjustable pulmonary vascular intervention balloon catheter according to claim 8, characterized in that, The enhanced imaging rings are respectively embedded in the grooves on the outer wall of the imaging mark slide. The enhanced imaging rings and the imaging mark slide are interference-fitted. The elastic reset member is sleeved on the outer wall of the conduit. The two ends of the elastic reset member abut against the side of the imaging mark slide and the fixing ring on the conduit, respectively. The pressure chamber wall is provided with a through hole corresponding to the position of the linkage push rod.

Images