Extended catheter and catheter system thereof

Abstract

The utility model relates to an extended catheter and a catheter system thereof. The utility model relates to an extended catheter and a catheter system thereof. The extended catheter comprises a catheter main body, a delivery rod and a catheter seat which are sequentially connected along the axial direction, an anchoring balloon is arranged on the outer side of the end, close to the delivery rod, of the catheter body, and the delivery rod is of a tubular structure. The delivery rod, the catheter seat and the anchoring balloon are communicated with one another; the catheter body comprises an inner-layer catheter body, a reinforcing-layer catheter body and an outer-layer catheter body which are arranged in a sleeving mode from inside to outside in the radial direction. The enhancement layer pipe body is a spiral cutting pipe layer or a stainless steel woven mesh layer or a spring layer. The extended catheter and the catheter system thereof have the advantages that the extended catheter can be used as a guiding instrument to be deeply inserted into the farther position of a blood vessel, the function of sucking thrombus and plaque can be achieved, exchange between instruments is reduced, and operation efficiency is improved.

Description

Technical Field

[0001] The utility model relates to the technical field of medical devices, in particular to an extension catheter and a catheter system thereof. Background Art

[0002] With the increasing number of patients undergoing percutaneous coronary intervention (PCI), especially with the aging of patients, the types of vascular lesions faced by interventional cardiologists are becoming increasingly complex. Many patients have severe tortuosity or calcification in their vessels, which can complicate stent implantation. Furthermore, patients with acute myocardial infarction often harbor significant thrombus in the affected vascular area. During anchored balloon angioplasty and stent implantation of occluded vessels, distal small vessels and microvessels can become blocked due to thrombus fragmentation and rupture of atherosclerotic plaques, leading to irreversible microcirculatory damage in the affected vascular territory. Compared with patients with stable angina, patients with acute myocardial infarction have a greater thrombus burden and risk of plaque rupture. During rapid revascularization, thrombus dislodgement can damage the microvascular network, compromising the efficacy of PCI. Therefore, when performing interventional therapy on vascular lesions in acute myocardial infarction, physicians must carefully assess the risks and adopt a comprehensive treatment strategy that rapidly opens the artery while protecting the distal microcirculation as much as possible to achieve optimal therapeutic outcomes.

[0003] Percutaneous coronary intervention (PCI) refers to the use of percutaneous puncture technology to deliver an anchored balloon catheter body or other related devices to relieve coronary artery stenosis or obstruction and reconstruct coronary blood flow. With the continuous development of medicine, medical interventional surgery has also made great progress. When the extension catheter in the related technology is placed in the inner lumen of the guiding catheter body, there will be a gap due to the fit, which not only causes the extension catheter to slip or even fall off, but also makes it impossible to achieve super-selective angiography in the coronary branch vessels. For complex PCI surgery, the catheter body needs to be replaced frequently, which not only prolongs the operation time, but also causes greater harm to the patient.

[0004] The current technical solutions for coronary interventional treatment mainly include extension catheters, thrombus aspiration catheter bodies and delivery catheter bodies. These catheter bodies often adopt the form of a mother-and-child catheter body. Although the mother-and-child catheter body can better solve the problem of deep insertion of the catheter body in complex lesions, for example, using the extension catheter as an extension of the guide catheter body can provide better stent delivery capabilities, there are some limitations. Specifically: there is a gap between the guide extension catheter body and the guide catheter body, which will reduce the negative pressure effect of aspirating thrombi and plaques, resulting in poor aspiration effect and failure to effectively solve the problem of microcirculation damage caused by thrombus and plaque detachment; the independent rapid exchange guidewire cavity of the thrombus aspiration catheter body will reduce the volume of the aspiration cavity, and large thrombi may be incompletely aspirated, increasing the risk of complications; the delivery catheter body adopts an integral exchange structure, which is more complicated and troublesome to operate and cannot achieve rapid exchange. Utility Model Content

[0005] Based on this, the purpose of the present invention is to provide an extension catheter and a catheter system thereof.

[0006] An extension catheter comprises a catheter body, a delivery rod and a catheter seat connected in sequence along the axial direction; an anchoring balloon is provided on the outer side of the catheter body near one end of the delivery rod, and the delivery rod has a tubular structure; the delivery rod, the catheter seat and the anchoring balloon are connected to each other; in the axial direction of the catheter body, the anchoring balloon is vacuum-flattened around the outer layer of the catheter body, and is tightly connected to the outer layer of the catheter body away from the end of the delivery rod, and is tightly connected to the catheter body and the delivery rod in pairs near the end of the delivery rod; a braided layer is provided on the outer side of the middle section of the delivery rod and a section near the catheter seat, and the braiding density of the braided layer of the middle section is greater than the braiding density of the braided layer of a section near the catheter seat, and the catheter body comprises an inner tube body, a reinforcement layer tube body and an outer tube body arranged radially from the inside to the outside; the reinforcement layer tube body is a spirally cut tube layer or a stainless steel braided mesh layer or a spring layer.

[0007] The extension catheter of the utility model delivers fluid media through the catheter seat and the delivery rod to inflate the anchoring balloon, fix the position of the catheter body, increase the axial stability of the catheter body, and at the same time have functions such as extension and suction, reduce the exchange between instruments, and improve surgical efficiency; the three-layer tube design allows the extension catheter to have strong negative pressure resistance and strong support.

[0008] Furthermore, the catheter body includes a catheter body channel and an instrument introduction port near the end of the delivery rod. The instrument introduction port is an oblique structure, forming a certain angle with the catheter body, and its cross-sectional area gradually decreases toward the delivery rod. The oblique structure provides better push delivery.

[0009] Furthermore, the catheter body further comprises a marker ring, which is arranged at one end of the catheter body away from the delivery rod and is used for imaging to show the position of the end of the catheter body.

[0010] Furthermore, the reinforcement layer includes a compliant section, a transition section, and a pushing section, which gradually approach the delivery rod along the axial direction and have decreasing flexibility. By changing the flexibility of the catheter body, the pushing requirement in the human blood vessel can be better met.

[0011] Furthermore, the reinforcement layer further comprises a metal connector; the metal connector is a metal ring arranged axially parallel to the catheter body and disposed within the reinforcement layer tube body near one end of the delivery rod. The metal connector is disposed parallel to the reinforcement layer on a side away from the delivery rod, and the metal connector is connected to the delivery rod on a side close to the delivery rod. The metal connector can effectively mitigate stress concentration at the connection between the catheter body and the delivery rod, while providing effective bending resistance for the catheter body and maintaining the integrity of the lumen when the anchoring balloon is inflated.

[0012] Furthermore, the delivery rod includes a through hole and a developing wire; the through hole is located in the middle of the anchoring balloon, connecting the delivery rod and the anchoring balloon; the developing wire plug is located in the through hole near one end of the catheter body and is disposed within the anchoring balloon. The developing wire is used to visualize the position of the anchoring balloon.

[0013] Furthermore, the delivery rod further comprises a spring wire, which is sleeved on the outside of the delivery rod and close to the metal connector. The spring wire reduces stress concentration after welding and improves the bending resistance of the end of the delivery rod.

[0014] Furthermore, the catheter body further includes a wire guide tube, which is disposed on the outer wall of the catheter body and connected in parallel with the catheter body along the direction of the catheter body. The provision of the wire guide tube allows the guide wire to pass through without occupying the area of ​​the catheter body, resulting in a relatively large effective area of ​​the catheter body and improved efficiency.

[0015] The present invention also provides a catheter system, comprising any of the above-described extension catheters, guide catheters and Y-type connecting valves; the Y-type connecting valve is provided with a first interface, a second interface and a third interface, the third interface is located on one side of the Y-type connecting valve and is connected to one end of the guiding catheter, the bifurcated first interface and second interface are located on the other side of the Y-type connecting valve and are respectively connected to the third interface; the first interface and the second interface are respectively connected to the guiding catheter through the third interface; the extension catheter extends into the guiding catheter from the first interface.

[0016] Furthermore, when the anchoring balloon is subjected to an inflation pressure of 0.8 bar to 1.5 bar, the anchoring balloon abuts against the inner wall of the guiding catheter, and the anchoring balloon can slide in the guiding catheter by moving the delivery rod.

[0017] In order to better understand and implement the present invention, the present invention is described in detail below with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 This is an overall schematic diagram of the catheter system of Example 1 of the present utility model;

[0019] Figure 2 This is an overall schematic diagram of the extension catheter of Example 1 of the present utility model;

[0020] Figure 3 This is a schematic diagram of the extension catheter of Example 1 of the present invention when the anchoring balloon is inflated;

[0021] Figure 4 for Figure 2 Schematic cross-section of the middle extension catheter at A;

[0022] Figure 5 This is a schematic cross-sectional view of a slit of the reinforcement layer of Example 1 of the present utility model;

[0023] Figure 6 This is a schematic diagram of the connection between the metal connector and the delivery rod in Example 1 of the present utility model;

[0024] Figure 7 This is a partially enlarged schematic diagram of the delivery rod of Example 1 of the present utility model;

[0025] Figure 8 This is a schematic diagram of the extension catheter of Example 2 of the present invention when the anchoring balloon is inflated. DETAILED DESCRIPTION

[0026] Example 1

[0027] Please refer to Figures 1 to 7A catheter system includes an extension catheter 1, a guiding catheter 2, a guide wire 3 and a Y-type connecting valve 4. The Y-type connecting valve 4 is provided with a first interface 41, a second interface 42 and a third interface 43. The third interface 43 is located on one side of the Y-type connecting valve 4 and is connected to one end of the guiding catheter 2. The bifurcated first interface 41 and second interface 42 are located on the other side of the Y-type connecting valve 4 and are respectively connected to the third interface 43. The first interface 41 and the second interface 42 are respectively connected to the guiding catheter 2 through the third interface 43, wherein the direction of the first interface 41 is the same as and coaxial with the direction of the opening of the guiding catheter 2 near the Y-type connecting valve 4. The extension catheter 1 extends into the guiding catheter 2 from the first interface 41, and the guide wire 3 extends into the extension catheter 1. During use, the end of the guiding catheter 2 away from the Y-type connecting valve 4 is inserted into the blood vessel, the guide wire 3 is preset in the guiding catheter 2, and passes through the guiding catheter 2 from the end of the guiding catheter 2 away from the Y-type connecting valve 4 to reach the thrombus 100, the extension catheter 1 is sleeved onto the outside of the guide wire 3 and enters the guiding catheter 2 along the guide wire 3, and at least a portion of the extension catheter 1 is located outside the first interface 41 so that it can be pushed to the designated position.

[0028] The extension catheter 1 includes a catheter body 11, a delivery rod 12 and a catheter seat 13, which are connected in sequence along the axial direction of the guiding catheter 2 from the end away from the Y-type connecting valve 4 to the end close to the Y-type connecting valve 4. The delivery rod 12 is close to the inner wall of the catheter body 11; the catheter seat 13 is flat in design, which is convenient for finger grip or rotation. The catheter seat 13 can drive the delivery rod 12 to rotate or translate along the guiding catheter 2. The delivery rod 12 applies force to move the catheter body 11 to the designated position. When in use, the catheter body 11 is sleeved on the outside of the guide wire 3 and is located in the guiding catheter 2, and the catheter seat 13 is located outside the first interface 41. Furthermore, a heparin cap or a one-way valve is provided at the open end of the catheter seat 13 to prevent the filled medium from flowing out of the catheter seat 13.

[0029] The catheter body 11 includes a catheter body channel 111 for delivering medical devices, an instrument introduction port 112 located at the end near the delivery rod 12, an anchoring balloon 113, an inner tube 114, a reinforcement layer 115, an outer tube 116, and a marker ring 117. The instrument introduction port 112 faces the catheter hub 13 and has an oblique structure, forming a certain angle with the catheter body 11, so that the cross-sectional area gradually decreases near the delivery rod 12, providing better push delivery. The anchoring balloon 113 is vacuum-wrapped and adhered to the outer layer of the catheter body 11; the anchoring balloon 113 on the side away from the delivery rod 12 is tightly welded to the outer layer of the catheter body 11 to form a sealed end, and the anchoring balloon 113, the catheter body 11 and the delivery rod 12 on the side close to the delivery rod 12 are tightly welded in pairs. The welding points at both ends of the entire anchoring balloon 113 have a smooth transition without obvious bumps and concave feels, and the entry into other channel instruments is smoother and with low resistance; the material of the anchoring balloon 113 is a mixture of one or more polyether front-end polyamide, polylaurolactam, and polyurethane elastomer.

[0030] Furthermore, a hydrophilic coating is provided on the surface of the anchoring balloon 113. When the anchoring balloon 113 is subjected to an inflation pressure of 0.8 bar to 1.5 bar, the anchoring balloon 113 abuts against the inner wall of the guiding catheter 2, and the anchoring balloon 5 can slide in the guiding catheter 2 by moving the delivery rod 12.

[0031] The inner tube body 114, the reinforcement layer tube body 115, and the outer tube body 116 are arranged in sequence along the radial direction of the guiding catheter 2 from the inside to the outside. The three-layer composite tube structure provides support, pressure resistance, and flexural resistance. The inner tube body 114 is made of one of polytetrafluoroethylene and high-density polyethylene, which provides low friction for other instruments to pass through. The reinforcement layer tube body 115 is a spiral cut tube layer or a stainless steel braided mesh layer or a spring layer. Its design gives the catheter body 11 strong negative pressure resistance and strong support. The outer tube body 116 is made of a mixture of one or more of polyether front-end polyamide, polylaurolactam, and polyurethane elastomer, giving the outer surface a smoother appearance and feel, fully protecting the blood vessels from thrombosis, dissection, etc. The stainless steel braided mesh layer and the spring layer are respectively stainless steel braided mesh or spring in the prior art, and the reinforcement layer 115 can be a stainless steel braided mesh layer tube or spring structure.

[0032] In this embodiment, the reinforced layer tube body 115 is a spirally cut tube layer, and includes a compliant section 1151, a transition section 1152, a push section 1153, and a metal connector 1154, each with decreasing axial flexibility. The compliant section 1151, the transition section 1152, and the push section 1153 are arranged in sequence and gradually approach the delivery rod 12. The outer circumferences of the flexible section 1151, the transition section 1152, and the pushing section 1153 are spirally surrounded with slits of different lengths extending axially along the guiding catheter 2. Different flexibility can be obtained by controlling the slit length, cutting angle, cutting spacing, and cutting pitch; the longer the slit, the smaller the cutting angle, the smaller the cutting spacing, and the smaller the cutting pitch, the higher the flexibility and the stronger the passability; the slit length of the flexible section 1151 is the longest, the cutting angle is the smallest, the cutting spacing is the smallest, and the cutting pitch is the smallest; the slit length of the pushing end 1153 is the shortest, the cutting angle is the largest, the cutting spacing is the largest, and the cutting pitch is the largest. In this embodiment, the slit width is 0.02mm, the overall length of the flexible section 1151 is 90mm, the slit length is 0.6mm, the cutting spacing is 0.1mm, the cutting angle is 95°, and the pitch is 0.09mm; the overall length of the transition section 1152 is 100mm, the slit length is 0.4mm, the cutting spacing is 0.3mm, the cutting angle is 105°, and the pitch is 0.12mm; the overall length of the pushing section 1153 is 160mm, the slit length is 0.1mm, the cutting spacing is 0.6mm, the cutting angle is 115°, and the pitch is 0.30mm. The metal connector 1154 is a metal ring arranged axially side by side along the guiding catheter 2, and is arranged in the reinforcing layer tube body 115 near one end of the delivery rod 12. Its cross-sectional shape is the same as the cross-sectional shape of the reinforcing layer tube body 115. In the axial direction of the guiding catheter 2, the metal connector 1154 is parallel to the reinforcing layer 115 on the side away from the delivery rod 12 but is not connected. The metal connector 1154 is connected to the delivery rod 12 on the side close to the delivery rod 12. The metal connector 1154 is superimposed and welded to the end of the delivery rod 12, and is designed to be hidden in the middle of the catheter body 11 so as not to cause damage to the blood vessels. The metal connector 1154 is a spiral structure as a whole, which can effectively buffer the stress concentration at the connection between the catheter body 11 and the delivery rod 12, while providing effective bending resistance for the catheter body 11, and can also keep the lumen intact when the anchoring balloon 113 is inflated. In this embodiment, the metal connector has a length of 19 mm, a spiral width of 0.35 mm, a pitch of 0.6 mm, and a welding area with the delivery rod of 0.1 mm to 1 mm.

[0033] The hardness of the catheter body 11 gradually decreases from one end close to the delivery rod 12 to the other end, which better meets the needs of pushing in human blood vessels, allowing doctors to operate more accurately and conveniently, and reducing the pain of patients during the operation.

[0034] The marking ring 117 is provided at one end of the catheter body 11 away from the delivery rod 12 and is used for visualization to show the position of the end of the catheter body 11 .

[0035] The delivery rod 12 can have a radial cross-section of one of elliptical, circular, or semi-arc shapes and is made of hypotube. The delivery rod 12 is a single-channel tubular structure, forming a fluid passageway. The section where the delivery rod 12 connects to the metal connector 1154 has a smaller diameter. Once connected to the metal connector 1154, the outer diameter of the entire connection is reduced.

[0036] The delivery rod 12 includes a through hole 121, a developing wire 122, a spring wire 123, a braided layer 124 and a delivery rod outer layer 125. The through hole 121 is arranged in the middle position of the anchoring balloon 113 and extends axially along the guiding catheter 2 to form the fluid channel. The through hole 121 is connected to the anchoring balloon 113. In this embodiment, the size of the through hole 121 is 0.1-0.2 mm. The developing wire 122 is plugged into the through hole 121 near one end of the catheter body 11 and is arranged in the anchoring balloon 113 for development, showing the position of the anchoring balloon 113, and accurately positioning it in the patient's body under X-rays, reducing the difficulty of operation. The developing wire 122 is one or more of gold wire, tungsten wire, platinum wire, and platinum-iridium alloy wire. In this embodiment, the length of the developing wire 122 is 5 mm. The spring wire 123 is sleeved on the outside of a section of the delivery rod 12 connected to the metal connector 1154, and is close to the metal connector 1154, to reduce stress concentration after welding, and at the same time improve the bending resistance of the end of the delivery rod 12, to prevent the end of the delivery rod 12 from bending during pushing. The diameter of the spring wire 123 is 0.05mm, the spacing is 0.07mm, and the material is nickel-titanium alloy or stainless steel. The braided layer 124 is respectively arranged on the middle section of the delivery rod 12 and the outside of a section close to the catheter seat. The braiding density of the braided layer 124 in the middle section is greater than the braiding density of the braided layer 124 in a section close to the catheter seat. The delivery rod outer layer 125 is sleeved on the entire outer layer of the delivery rod 12.

[0037] In this embodiment, the middle section of the delivery rod 12 uses a braided layer 124 with a stitch count of 100 per inch, which provides good lumen retention, torque transmission, and certain pushing performance. The end of the delivery rod 12 near the catheter adapter 13 uses a braided layer 124 with a stitch count of 50 per inch, which provides good pushing ability. The braided layer 124 can be woven with stainless steel wire. The outer layer 125 of the delivery rod is a polytetrafluoroethylene layer, which provides low friction on the surface and reduces the probability of thrombus entrapment in the body. The polytetrafluoroethylene layer can be prepared using a polytetrafluoroethylene coating.

[0038] Furthermore, in order to facilitate medical personnel to know the depth to which the catheter body 11 and the anchoring balloon 113 are inserted into the human body, a scale or marking band is provided on the surface of the delivery rod 12 .

[0039] During welding, the metal of the delivery rod 12 is welded to the reinforcement layer tube 115 of the catheter body 11 . During the welding process, the polymer will melt, allowing the two metals to contact and weld.

[0040] The catheter adapter 13 is interconnected with the fluid channel. The catheter adapter 13, the delivery rod 12, and the anchoring balloon 113 are interconnected to form a single-lumen channel. A physician can connect an injector fluid or other medium to the catheter adapter 13 to inflate the anchoring balloon 113, allowing it to quickly anchor within the lumen of the guiding catheter 2 and provide a closure.

[0041] Taking the example of entering a small blood vessel to aspirate a thrombus 100, the catheter system of the present invention operates as follows: The end of the guiding catheter 2, distal to the Y-shaped connecting valve 4, is delivered to a larger blood vessel in the human body near the small vessel. The guidewire 3 is then passed through the first interface 41 of the Y-shaped connecting valve 4 and along the guiding catheter 2 to the thrombus 100 in the small vessel. The extension catheter 1 is then delivered along the guidewire 3, extending into the guiding catheter 2 from the first interface 41. The end of the catheter body 11, distal to the delivery rod 12, emerges from the guiding catheter 2. The other end of the catheter body 11 is located within the guiding catheter 2. One end of the delivery rod 12 is located within the guiding catheter 2, and the other end emerges from the first interface 211. Guided by the guidewire 3, the catheter body 11 enters the finger anchoring position, and the delivery rod 12 applies force, making it easier to enter branch vessels and narrow blood vessels. A fluid medium is delivered through the catheter adapter 13 and the fluid channel to fill the anchoring balloon 113. After the anchoring balloon 113 is inflated and expanded, it is anchored in the guiding catheter 2. The anchoring balloon 113 blocks the gap between the guiding catheter 2 and the catheter body 11. The first interface 211 is blocked, and contrast agent / drug is delivered through the second interface 212. The contrast agent / drug flows along the guiding catheter 2 into the catheter body channel 111 of the catheter body 11, and then flows out along the catheter body 11 to small blood vessels, thereby performing super-selective angiography / targeted drug administration. The first interface 211 is blocked, and an aspirator is externally connected to the second interface 212 to aspirate thrombus 100 or plaque. The thrombus 100 or calcified plaque, etc., flows back into the guiding catheter 2 along the catheter body channel 111 of the catheter body 11 under the action of negative pressure until it is withdrawn from the body. An external pressure pump is used to withdraw the medium in the anchoring balloon 113 . Through fluoroscopy with other equipment, it is confirmed that the anchoring balloon 113 is deflated and no medium remains. The guide wire 3 and the extension catheter 1 are withdrawn as a whole until they are out of the body.

[0042] Example 2

[0043] See also Figure 8 The structure of this embodiment is basically the same as that of the first embodiment, except that the extension catheter 1 further includes a guide wire tube 14. The guide wire tube 14 is disposed on the outer wall of the catheter body 11 and is connected to the catheter body 11 in parallel along the direction of the catheter body 11; one end of the guide wire tube 14 is located at the end of the anchoring balloon 113 close to the delivery rod 12, and the other end extends to the end of the catheter body 11 away from the delivery rod 12. The guide wire 3 is passed through the guide wire tube 14.

[0044] By providing the guidewire tube 14, the guidewire 3 can pass through the guidewire tube 14 without occupying the area of ​​the catheter body channel 111. This ensures a smooth suction path through the catheter body channel 111, a relatively large effective suction area, and improved suction efficiency. Simultaneously, the guidewire 3 passing through the guidewire tube 14 can guide and anchor the catheter body 11, ensuring that the catheter body 11 can be accurately delivered to the target area. Furthermore, because the guidewire 3 does not occupy the area of ​​the catheter body channel 111 of the catheter body 11, the effective suction area is relatively large, improving suction performance for large thrombi 300 and reducing complications.

[0045] In the catheter system of the present invention, when the anchoring balloon 113 is not inflated, the extension catheter 1 slides inside the guiding catheter 2, and the guidewire 3 can movably pass through the guiding catheter 2 and the guidewire cavity; when the anchoring balloon 113 is inflated, the anchoring balloon 113 expands and abuts against the inner wall of the guiding catheter 2 and the guidewire 3, and the catheter body 11 is connected to the guiding catheter 2, thereby enhancing the axial stability of the extension catheter 1 in the guiding catheter 2, and the anchoring balloon 5 can be made to slide inside the guiding catheter 2 by moving the delivery rod 12. The extension catheter 1 of the present invention can be used as a guiding instrument to be deeply inserted into a more distant position in the blood vessel, and can also achieve super-selective angiography or thrombus 100 and plaque aspiration functions, reducing thrombotic events caused by thrombus 100 aspiration, reducing the exchange between instruments, and improving surgical efficiency.

[0046] The above-described embodiments merely represent several implementation methods of the present invention. While the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the patent. It should be noted that a person skilled in the art would be able to make numerous modifications and improvements without departing from the concept of the present invention, and the present invention is intended to encompass such modifications and variations.

Claims

1. An extension catheter, characterized in that: It comprises a catheter body, a delivery rod and a catheter seat connected in sequence along the axial direction; an anchoring balloon is provided on the outer side of one end of the catheter body near the delivery rod, and the delivery rod has a tubular structure; the delivery rod, the catheter seat and the anchoring balloon are connected to each other; in the axial direction of the catheter body, the anchoring balloon is vacuum-flattened and wrapped around the outer layer of the catheter body, and is tightly connected to the outer layer of the catheter body away from the end of the delivery rod, and the anchoring balloon is tightly connected to the catheter body and the delivery rod in pairs at one end near the delivery rod; a woven layer is provided on the outer side of the middle section of the delivery rod and a section near the catheter seat, and the woven density of the woven layer of the middle section is greater than the woven density of the woven layer of the section near the catheter seat, and the catheter body comprises an inner tube body, a reinforcement layer tube body and an outer tube body arranged radially from the inside to the outside; the reinforcement layer tube body is a spirally cut tube layer or a stainless steel woven mesh layer or a spring layer.

2. The extension catheter according to claim 1, characterized in that: The catheter body includes a catheter body channel and an instrument introduction port near the end of the delivery rod; the instrument introduction port is an oblique structure, forming a certain angle with the catheter body, and the cross-sectional area gradually decreases near the delivery rod.

3. The extension catheter according to claim 2, characterized in that: The catheter body further comprises a marker ring; the marker ring is arranged at one end of the catheter body away from the delivery rod.

4. The extension catheter according to claim 1, wherein: The reinforcing layer comprises a compliant section, a transition section and a pushing section which gradually approach the delivery rod along the axial direction and whose flexibility decreases successively.

5. The extension catheter according to claim 4, characterized in that: The reinforcing layer also includes a metal connector; the metal connector is a metal ring arranged side by side along the axial direction of the catheter body, and is arranged in the reinforcing layer tube body close to one end of the delivery rod. The metal connector is arranged side by side with the reinforcing layer away from the delivery rod, and the metal connector is connected to the delivery rod on the side close to the delivery rod.

6. The extension catheter according to claim 5, characterized in that: The delivery rod includes a through hole and a developing wire; the through hole is arranged in the middle of the anchoring balloon, connecting the delivery rod and the anchoring balloon; the developing wire plug is located in the through hole near one end of the catheter body and is arranged in the anchoring balloon.

7. The extension catheter according to claim 6, characterized in that: The delivery rod further comprises a spring wire; the spring wire is sleeved on the outside of the delivery rod and is close to the metal connecting piece.

8. The extension catheter according to claim 1, characterized in that: A heparin cap or a one-way valve is provided at the open end of the catheter seat.

9. The extension catheter according to claim 1, characterized in that: The surface of the delivery rod is provided with scales or marking strips.

10. The extension catheter according to any one of claims 1 to 9, characterized in that: The catheter body further comprises a wire guide tube; the wire guide tube is arranged on the outer wall of the catheter body and is connected to the catheter body in parallel along the direction of the catheter body.

11. A catheter system, characterized in that: It includes the extension catheter, guiding catheter and Y-type connecting valve according to any one of claims 1 to 10; the Y-type connecting valve is provided with a first interface, a second interface and a third interface, the third interface is located on one side of the Y-type connecting valve and is connected to one end of the guiding catheter, the forked first interface and second interface are located on the other side of the Y-type connecting valve and are respectively connected to the third interface; the first interface and the second interface are respectively connected to the guiding catheter through the third interface; the extension catheter extends from the first interface into the guiding catheter.

12. The catheter system according to claim 11, wherein When the anchoring balloon is subjected to an inflation pressure of 0.8 bar to 1.5 bar, the anchoring balloon abuts against the inner wall of the guiding catheter, and the anchoring balloon can be slid inside the guiding catheter by moving the delivery rod.

Images