A dilating catheter

Abstract

This invention discloses an expansion catheter, relating to the field of interventional medical device technology, comprising an inner tube, an outer tube, a tip tube, and a radial expansion assembly. The inner tube passes through the lumen of the outer tube, with its distal end extending outward from the distal opening of the outer tube. The tip tube is located at the distal end of the outer tube and is fixedly connected to the inner tube. The radial expansion assembly is a deformable structure capable of radially expanding outward relative to the outer tube. The radial expansion assembly includes multiple radial expansion elements arranged circumferentially around the inner tube, with the proximal ends of the multiple radial expansion elements connected to the outer tube and the distal ends connected to the tip tube. When the outer tube is subjected to an axial force toward the distal end, the multiple radial expansion elements expand outward under the action of the outer tube, which can expand the inner wall of the blood vessel instead of the balloon, avoiding damage to the blood vessel caused by the balloon bursting due to excessive inflation pressure, thus improving safety. Moreover, it eliminates the need for manual operation of a pressure pump to control the balloon inflation pressure, reducing the operational difficulty of vascular dilation surgery.

Description

Technical Field

[0001] This invention relates to the field of interventional medical device technology, specifically to an dilation catheter. Background Technology

[0002] In interventional treatment of arterial occlusion, an inflatable balloon placed on a catheter is typically used to dilate the blocked artery, and cutting tools on the periphery of the balloon are used to cut the plaque on the inner wall of the artery, thereby restoring arterial patency and improving blood flow.

[0003] Balloons are usually inflated using a pressure pump connected to the proximal end of the catheter. Because the balloon has a very small expansion volume, if the pressure pump is not operated manually, the pressure after inflation can easily become too high, which could lead to the balloon bursting and damaging the blood vessel.

[0004] Therefore, there is a need for a dilation catheter that can perform dilation treatment on the inner wall of blood vessels and has good safety. Summary of the Invention

[0005] In view of this, the present invention provides an dilation catheter to solve the problems of existing balloon dilation catheters, which use balloon inflation to dilate the inner wall of blood vessels for treatment, and the high risk of balloon rupture and easy damage to blood vessels if the operation is not careful.

[0006] To solve the above-mentioned technical problems, the technical solution of the present invention is as follows: An expansion catheter includes an inner tube, an outer tube, a tip tube, and a radial expansion assembly; the inner tube passes through the lumen of the outer tube, the distal end of the inner tube extends outward from the distal opening of the outer tube, and the tip tube is located at the distal end of the outer tube and is fixedly connected to the inner tube. The radial expansion assembly is a deformable structure capable of radially expanding outward relative to the outer tube. The radial expansion assembly includes a plurality of radial expansion elements arranged circumferentially around the distal end of the inner tube. The proximal ends of the plurality of radial expansion elements are all connected to the outer tube, and the distal ends of the plurality of radial expansion elements are all connected to the head end tube or the inner tube. When the inner tube is fixed in position and the outer tube is subjected to an axial force toward the distal end, the plurality of radial expansion elements of the radial expansion assembly expand radially outward, and after radial outward expansion, the plurality of radial expansion elements can expand the inner wall of the blood vessel.

[0007] Furthermore, the radial expansion element is a strip-shaped connector that is long and can elastically bend and deform in its middle when subjected to force. The proximal end of the strip-shaped connector is fixedly connected to the distal end of the outer tube, and the distal end of the strip-shaped connector is fixedly connected to the proximal end of the head tube.

[0008] Furthermore, a portion of the strip connector facing away from the inner tube or the entire strip connector forms a pressure focusing protrusion for cutting or squeezing the patch.

[0009] Furthermore, the length direction of the strip connector is in the same direction as the axial direction of the outer tube.

[0010] Furthermore, the pressure focusing protrusion is a cutting element for cutting patches, the cutting element having a triangular cross-section and having a blade and cutting edge for cutting the patches; or, the pressure focusing protrusion is a scoring element for squeezing patches, the scoring element having a triangular or trapezoidal cross-section and having a pressure-bearing apex or squeezing edge for squeezing patches to form scoring.

[0011] Furthermore, the strip connector is a straight strip connector with equal width at all points along the axial direction; or, The strip connector is a gradually widening strip connector with its width continuously increasing from the middle to both ends; or, the strip connector is a multi-step widening strip connector with its width gradually increasing from the middle to both ends. Both the gradually widening and multi-step widening strip connectors enhance the support strength of the strip connector by continuously increasing the width of the ends, thereby better cutting and compressing plaque on the vascular wall.

[0012] Furthermore, the strip connector is provided with a plurality of developing marks arranged at intervals along its own length.

[0013] Furthermore, the radial expansion element is a hinged support bracket composed of multiple rigid connectors hinged together. When the hinged support bracket is subjected to force, each rigid connector rotates relative to the hinge point to change the angle between each rigid connector, thereby realizing the radial expansion of the hinged support bracket relative to the outer tube.

[0014] Furthermore, the articulated support bracket includes a first bottom rigid connector, a second bottom rigid connector, a third bottom rigid connector, a middle rigid connector, a proximal shoulder rigid connector, a distal shoulder rigid connector, and an internal rigid connector; The first bottom rigid connector is fixed to the outside of the inner tube, the second bottom rigid connector is fixed to the outside of the outer tube, and the third bottom rigid connector is fixed to the outside of the outer tube and located between the first bottom rigid connector and the second bottom rigid connector. The proximal end of the proximal shoulder rigid connector is hinged to the second bottom rigid connector, the distal end of the distal shoulder rigid connector is hinged to the first bottom rigid connector, the proximal end of the intermediate rigid connector is hinged to the distal end of the proximal shoulder rigid connector, and the proximal end of the intermediate rigid connector is hinged to the proximal end of the distal shoulder rigid connector. The proximal end of the internal rigid connector is hinged to the third bottom rigid connector, and the distal end of the internal rigid connector is hinged to the distal shoulder rigid connector.

[0015] When the inner tube is fixed in position and the outer tube is subjected to an axial force toward the far end, the outer tube drives the second and third bottom rigid connectors to move toward the far end, thereby causing the proximal shoulder rigid connector and the inner rigid connector to open synchronously, and further causing the middle rigid connector and the far shoulder rigid connector to lift up. Through the combined action of the third bottom rigid connector and the proximal shoulder rigid connector, the middle rigid connector can expand radially outward relative to the outer tube.

[0016] Furthermore, the intermediate rigid connector has a pressure focusing protrusion on the side facing away from the inner tube for cutting or squeezing the plaque.

[0017] Furthermore, in the hinged support bracket, one of the two rigid connecting members that are hinged to each other is provided with a limiting groove, and the other is provided with a limiting platform that cooperates with the limiting groove. A limiting step surface that cooperates with the limiting platform and the limiting groove is provided. The limiting step surface is used to restrict the rigid connecting member with the limiting groove to rotate only on one side of the other rigid connecting member that is hinged to each other.

[0018] Furthermore, the bottom of the limiting groove is provided with a hemispherical groove, and the end of the limiting platform is provided with a hemispherical boss, the boss being rotatably engaged with the groove.

[0019] Furthermore, the dilation catheter also includes a sealing and limiting ring that is fixedly connected to the inside of the outer tube and movably sleeved on the outer periphery of the inner tube.

[0020] Furthermore, the sealing limiting ring is provided with a developing mark.

[0021] Furthermore, the dilation catheter also includes a handle, and the proximal ends of both the inner tube and the outer tube are connected to the handle. The handle is provided with an outer tube pusher for applying an axial force to the outer tube.

[0022] The dilation catheter provided by this invention has the following advantages: A radial dilation component capable of expanding radially outward relative to the outer tube is provided at the distal end of the outer tube. This radial dilation component includes multiple radial dilation elements arranged axially around the inner tube and possessing a deformable structure. When the outer tube is subjected to an axial force towards the distal end, the multiple radial dilation elements of the radial dilation component expand radially outward, thereby dilating the inner wall of the blood vessel. This radial dilation component can replace a balloon for vascular dilation treatment, avoiding damage to the blood vessel caused by balloon rupture due to excessive inflation pressure, thus improving safety. Furthermore, it eliminates the need for manual operation of a pressure pump to control the balloon inflation pressure, reducing the operational difficulty of vascular dilation surgery and lowering the technical requirements for operators. Attached Figure Description

[0023] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0024] Figure 1 This is a schematic diagram of the overall structure of the dilation catheter in Embodiment 1 of the present invention, wherein multiple strip connectors are in an expanded state; Figure 2 This is a partial structural diagram of the distal end of the dilation catheter in Embodiment 1 of the present invention, wherein multiple strip-shaped connectors are in an expanded state; Figure 3 This is a schematic diagram of the overall structure of the dilation catheter in Embodiment 1 of the present invention, wherein one half of the handle is hidden to show the internal structure of the handle; Figure 4 for Figure 3 A schematic diagram of a partial structure at the distal end of the dilation catheter, showing multiple strip connectors in an undilated state; Figure 5 for Figure 4 A cross-sectional view of the AA plane; Figure 6 This is a three-dimensional structural diagram of the strip connector in Embodiment 1 of the present invention; Figure 7 This is a schematic diagram of the structure of the strip connector after being bent under stress in Embodiment 1 of the present invention; Figure 8 This is a schematic diagram of the cross-section of the pressure focusing protrusion in Embodiment 1 of the present invention being triangular; Figure 9 This is a schematic diagram of the cross-section of the pressure focusing protrusion in Embodiment 1 of the present invention being trapezoidal; Figure 10This is a schematic diagram of the structure of the strip connector in Embodiment 1 of the present invention when it is straight; Figure 11 This is a schematic diagram of the structure of the strip connector in Embodiment 1 of the present invention when it has a gradually flared shape; Figure 12 This is a schematic diagram of the structure of the strip connector in Embodiment 1 of the present invention when it has a multi-step flared shape; Figure 13 This is a schematic diagram of the overall structure of the dilation catheter in Embodiment 2 of the present invention, wherein the hinged support bracket is in an undilated state; Figure 14 This is a schematic diagram of the structure of the distal articulated support stent of the dilation catheter in the undilated state in Embodiment 2 of the present invention; Figure 15 This is a simplified schematic diagram of the structure of the distal articulated support stent of the dilation catheter in the dilation state in Embodiment 2 of the present invention; Figure 16 This is a three-dimensional structural diagram of the hinged support bracket in the expanded state according to Embodiment 2 of the present invention; Figure 17 This is a three-dimensional structural diagram of the first bottom rigid connector in Embodiment 2 of the present invention; Figure 18 This is a three-dimensional structural diagram of the intermediate rigid connector in Embodiment 2 of the present invention; Figure 19 This is a cross-sectional view of the intermediate rigid connector in Embodiment 2 of the present invention; Figure 20 This is a three-dimensional structural diagram of the rigid connector at the proximal shoulder in Embodiment 2 of the present invention; Figure 21 This is a three-dimensional structural diagram of the rigid connector at the distal shoulder in Embodiment 2 of the present invention; Figure 22 This is a three-dimensional structural diagram of the internal rigid connecting member in Embodiment 2 of the present invention.

[0025] Explanation of reference numerals: 100, Inner tube; 120, Inner tube development mark; 200, Outer tube; 300, Head end tube; 400, Handle; 410, Handle housing; 420, Outer tube pusher; 430, Outer tube fixing component; 440, Inner tube fixing component; 450, Stress relief tube; 500, Radial expansion assembly; 510, Strip connector; 510a, Straight strip connector; 510b, Gradient flared strip connector; 510c, Multi-step flared strip connector Components; 511, Development mark; 520, Hinged support bracket; 521, First bottom rigid connector; 522, Second bottom rigid connector; 523, Third bottom rigid connector; 524, Intermediate rigid connector; 525, Proximal shoulder rigid connector; 526, Distal shoulder rigid connector; 527, Internal rigid connector; 530, Pressure focusing protrusion; 530a, Cutting component; 530b, Scoring component; 600, Sealing limit ring; 700, Guide wire. Detailed Implementation

[0026] The technical solution of the present invention will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0027] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances. In the description of this invention, it should be understood that the terms "proximal" and "distal" throughout the text refer to near and far relative to the operator. In use, the end closer to the doctor or operator is the "proximal" end, i.e., the end where the operator is located, and the end farther from the doctor or operator is the "distal" end.

[0028] In current interventional treatments for arterial occlusion, an inflatable balloon placed at the distal end of a catheter is typically used to dilate the blocked artery. Cutting or scoring elements on the periphery of the balloon are then used to cut or compress the inner wall of the blood vessel, thereby restoring arterial patency and improving blood flow.

[0029] However, the balloon at the distal end of the catheter needs to be inflated using a pressure pump. Because the balloon's expansion volume is very small, even slight mishandling of the pressure pump can easily lead to excessive pressure after inflation, potentially causing the balloon to burst and damage the blood vessel. These balloon-equipped dilatation catheters require a high level of operator skill and pose certain safety risks. To address these problems, this invention provides a dilatation catheter that eliminates the need for a balloon, is simple to operate, and can dilate the inner wall of the blood vessel.

[0030] Example 1 like Figures 1 to 4 The illustrated dilator includes an inner tube 100, an outer tube 200, a tip tube 300, a handle 400, and a radial dilation assembly 500. The inner tube 100 passes through the lumen of the outer tube 200, and the outer tube 200 and inner tube 100 are axially movable relative to each other. The outer tube 200 can be made of metal or polymer material and has a certain rigidity; the outer tube 200 can reliably transmit the axial force received at its proximal end to its distal end. The proximal ends of both the inner tube 100 and the outer tube 200 are connected to the handle 400. The handle 400 is provided with an outer tube pusher 420 for applying axial force to the outer tube 200. The distal end of the inner tube 100 extends outward from the distal opening of the outer tube 200, and the tip tube 300 is located at the distal end of the outer tube 200 and is fixedly connected to the distal end of the inner tube 100.

[0031] like Figures 1 to 4 As shown, the proximal end of the radial dilation component 500 is connected to the distal end of the outer tube 200, and the distal end of the radial dilation component 500 is connected to the proximal end of the tip tube 300. The radial dilation component 500 is a deformable structure capable of radially expanding outward relative to the outer tube 200. The lumen of the inner tube 100 allows the guidewire 700 to pass through, and the radial dilation component 500 of the dilation catheter can be delivered along the guiding direction of the guidewire 700 to the location of the stenotic lesion.

[0032] like Figures 1 to 4As shown, after the radial dilation component 500 of the dilation catheter reaches the narrowed lesion, the inner tube 100 and the tip tube 300 are fixed in position. The outer tube pusher 420 is pushed distally, which drives the outer tube 200 distally. Under the axial thrust of the outer tube 200, the radial dilation component 500 expands radially outward along the inner tube 100, forming a spherical expansion body. After expansion, the radial dimension of the radial dilation component 500 increases, allowing it to dilate the inner wall of the blood vessel. After the vascular dilation treatment is completed, the outer tube pusher 420 is withdrawn proximally, and the expanded radial dilation component 500 returns to its initial state. At this point, the radial dimension of the radial dilation component 500 decreases, facilitating the withdrawal of the dilation catheter from the blood vessel. In actual operation, the displacement of the outer tube pusher 420 can be controlled to achieve different degrees of dilation in the radial dilation component 500, and the diameter of the radial dilation component 500 in the dilated state can be adjusted to meet the dilation treatment needs of different narrowed blood vessels in clinical practice.

[0033] like Figures 1 to 4 As shown, the radial expansion assembly 500 includes a plurality of radial expansion elements arranged circumferentially at intervals around the distal end of the inner tube 100. The number of radial expansion elements can be set to three or more as needed, with the three or more radial expansion elements evenly spaced circumferentially around the distal end of the inner tube 100. In this embodiment, the radial expansion elements are specifically elongated strip-shaped connectors 510. The proximal ends of the plurality of strip-shaped connectors 510 are fixedly connected to the outer tube 200, and the distal ends of the plurality of strip-shaped connectors 510 are fixedly connected to the head end tube 300. (Combined with...) Figure 7 As shown, the strip connector 510 itself has bending elasticity. When the strip connector 510 is subjected to force, its middle part can undergo elastic bending deformation, forming an arched shape with the middle part arching outward. When the outer tube 200 is subjected to an axial force towards the distal end, the middle parts of the multiple strip connectors 510 expand radially outward, and the multiple strip connectors 510 form an arched shape with the middle part arched. The arched part of the middle part of the multiple strip connectors 510 can support and expand the inner wall of the blood vessel.

[0034] like Figures 1 to 4 As shown, the radial expansion assembly 500 also includes an expansion element coating layer (not shown) covering the periphery of the plurality of strip connectors 510. The material of the expansion element coating layer can be a polymer material that combines elasticity and biocompatibility, such as polyurethane or silicone rubber. The expansion element coating layer plays a sealing role, preventing blood from flowing into the gap between adjacent strip connectors 510 and preventing the strip connectors 510 from damaging blood vessels.

[0035] like Figure 3 and Figure 4As shown, the handle 400 includes a handle housing 410, an outer tube pusher 420, an outer tube fixator 430, an inner tube fixator 440, and a stress relief tube 450. The handle housing 410 is formed by joining a pair of handle half-housings. The outer tube fixator 430 is disposed within the handle housing 410 and fixedly connected to the proximal end of the outer tube 200, maintaining a relative axial sliding arrangement with the handle housing 410. The inner tube fixator 440 is disposed within the handle housing 410 and located near the proximal end of the outer tube fixator 430, maintaining a relative axial sliding arrangement with the outer tube fixator 430, and fixedly connected to the proximal end of the inner tube 100. The outer tube pusher 420 is connected to the outer tube fixator 430 and slidably connected to a groove on the handle housing 410, and the outer tube pusher 420 applies an axial force to the outer tube 200 through the outer tube fixator 430. The stress relief tube 450 is connected to the far end of the handle housing 410 and is sleeved on the outer periphery of the outer tube 200.

[0036] like Figure 3 , Figure 4 and Figure 5 As shown, the dilation catheter also includes a sealing and limiting ring 600 fixedly connected inside the outer tube 200. The sealing and limiting ring 600 is located at one end of the outer tube 200 near the strip connector 510, and is movably sleeved on the outer periphery of the inner tube 100. When the outer tube 200 is pushed axially, the sealing and limiting ring 600 moves axially relative to the inner tube 100 along with the outer tube 200. Specifically, the sealing and limiting ring 600 is fixed inside the outer tube 200 by welding, bonding, or other methods. The sealing and limiting ring 600 can seal the space between the inner tube 100 and the outer tube 200, preventing blood from flowing out through the gap between the inner tube 100 and the outer tube 200 after the dilation catheter enters the blood vessel. The sealing and limiting ring 600 can also keep the outer tube 200 and the inner tube 100 coaxial and fixed in relative position, preventing the distal end of the outer tube 200 from being crushed and deformed by the reaction force after the strip connector 510 is bent when it is under force, and can better maintain the expanded state of the bent strip connector 510, so as to achieve a continuous expansion effect on the inner wall of the blood vessel.

[0037] like Figure 3 and Figure 4 As shown, in some embodiments, the sealing and limiting ring 600 itself has a imaging function. The sealing and limiting ring 600 is relatively large in size, and the imaging effect is better, which makes it easier to locate the position of the strip connector 510 in the blood vessel.

[0038] like Figure 3 and Figure 4As shown, in some embodiments of this example, each strip connector 510 is provided with a plurality of development marks 511 arranged at intervals along its own length direction. For example, there are four development marks 511, which are evenly spaced along the length direction of the strip connector 510. One development mark 511 is located at the far end of the strip connector 510 closest to the head tube 300, another development mark 511 is located at the near end of the strip connector 510 closest to the outer tube 200, and the other two development marks 511 are located in the middle of the strip connector 510. When the strip connector 510 is not expanded, the four imaging marks 511 on the strip connector 510 are on the same straight line. When the middle part of the strip connector 510 arches outward, the two imaging marks 511 in the middle arch outward relative to the radial direction of the outer tube 200. The four imaging marks 511 are arranged in an arch shape. Clinically, the shape of the strip connector after bending under force can be judged by observing the shape of the four imaging marks 511. The degree of bending of the strip connector 510 can be reasonably controlled to achieve control of the vasodilatory effect.

[0039] like Figure 2 , Figure 6 and Figure 7 As shown, in this embodiment, the entire strip connector 510 or a portion of the strip connector 510 facing away from the inner tube 100 forms a pressure focusing protrusion 530 for cutting or squeezing patches. In some embodiments of this embodiment, the length direction of the pressure focusing protrusion 530 is in the same direction as the axial direction of the outer tube 200. In alternative embodiments, the shape of the pressure focusing protrusion 530 is not limited to a long strip, but can also be other complex shapes. Different shapes of pressure focusing protrusions 530 can achieve different squeezing and scoring effects.

[0040] like Figure 8 As shown, in some embodiments of this example, the pressure focusing protrusion 530 is a cutting element 530a for cutting patches. The cutting element 530a has a triangular cross-section and has a blade and cutting edge for cutting the patches. Figure 9 As shown, in some other embodiments of this example, the pressure focusing protrusion 530 is a scoring element 530b for compressing the plaque. The scoring element 530b has a trapezoidal cross-section and has a pressure-bearing apex or compression ridge for forming a score on the plaque. The cutting element 530a and the scoring element 530b can also be other shapes. The cutting element 530a can have the same structure as the cutting element on the periphery of the balloon in a conventional balloon dilation catheter, and the scoring element 530b can also have the same structure as the scoring element on the periphery of the balloon in a conventional balloon dilation catheter.

[0041] like Figure 10As shown, in the first embodiment of the strip connector 510, the strip connector 510 is a straight strip connector 510a with equal width at all points along the axial direction. The straight strip connector 510a has a simple structure and is easy to manufacture.

[0042] like Figure 11 As shown, in the second embodiment of the strip connector 510, the strip connector 510 is a gradually widening strip connector 510b with its width continuously increasing from the middle to both ends. The gradually widening strip connector 510b enhances the support strength of the strip connector 510 by continuously increasing the width of the two ends of the strip connector 510, thereby enabling it to better cut and compress plaque on the inner wall of the blood vessel.

[0043] like Figure 12 As shown, in the third embodiment of the strip connector 510, the strip connector 510 is a multi-step flared strip connector 510c with its width gradually increasing from the middle to both ends. The multi-step flared strip connector 510c enhances the support strength of the strip connector 510 by continuously and intermittently increasing the width of the two ends of the strip connector 510, and can also better cut and compress plaque on the inner wall of the blood vessel.

[0044] The dilating catheter provided in Embodiment 1 of this invention, when dilating the inner wall of a blood vessel, involves holding the handle 400 and pushing the outer tube pusher 420 distally. The outer tube pusher 420 drives the outer tube fixation member 430 and the outer tube 200 distally. Since the positions of the inner tube 100 and the tip tube 300 are fixed at this time, and the distal ends of the multiple strip connectors 510 are fixedly connected to the outer tube 200, the middle portions of the multiple strip connectors 510 are subjected to compressive force and arch radially outward. As the displacement of the outer tube pusher 420 increases, the height of the arch in the middle of the multiple strip connectors 510 increases until it supports the inner wall of the dilated blood vessel, achieving the effect of dilating the blood vessel. When the strip connectors 510 dilate the inner wall of the blood vessel, the pressure focusing protrusions 530 of the strip connectors 510 can compress or scratch the plaque on the inner wall of the blood vessel, further improving the dilation treatment effect of the inner wall of the blood vessel. After the vasodilation treatment is completed, the outer tube pusher 420 is retracted proximally, and the multiple strip connectors 510 gradually return to their initial straight state, making it easier to push out the dilation catheter.

[0045] Example 2 like Figures 13 to 22The difference between the expansion catheter shown and Embodiment 1 lies primarily in the structural form of the radial expansion element. In Embodiment 2, the radial expansion element is a hinged support bracket 520 composed of multiple rigid connectors hinged together. When the hinged support bracket 520 is subjected to force, each rigid connector rotates relative to the hinge point to change the angle between the rigid connectors, thereby achieving radial expansion of the hinged support bracket 520 relative to the outer tube 200. The multiple rigid connectors can be made of a material with imaging function. Each of the multiple rigid connectors itself possesses a certain degree of rigidity.

[0046] like Figures 13 to 15 As shown, an inner tube imaging marker 120 with imaging function is fixed to the distal end of the inner tube 100, and the inner tube imaging marker 120 is fixed to the proximal end of the tip tube 300. The distal end of the articulated support stent 520 is connected to the inner tube imaging marker 120, and the proximal end of the articulated support stent 520 is connected to the outer tube 200. The inner tube imaging marker 120 is used to indicate the position of the articulated support stent 520 within the blood vessel.

[0047] like Figure 15 As shown, in some embodiments of Embodiment 2, the articulated support bracket 520 includes a first bottom rigid connector 521, a second bottom rigid connector 522, a third bottom rigid connector 523, an intermediate rigid connector 524, a proximal shoulder rigid connector 525, a distal shoulder rigid connector 526, and an internal rigid connector 527.

[0048] like Figure 15 As shown, the first bottom rigid connector 521 is fixed to the outside of the distal end of the inner tube 100 by welding or bonding, and the first bottom rigid connector 521 is located near the end of the inner tube imaging mark 120. The second bottom rigid connector 522 is fixed to the outside of the outer tube 200 by welding or bonding. The third bottom rigid connector 523 is fixed to the outside of the distal end of the outer tube 200 by welding or bonding, and the third bottom rigid connector 523 is located between the first bottom rigid connector 521 and the second bottom rigid connector 522.

[0049] like Figure 15 As shown, the distal end of the distal shoulder rigid connector 526 is hinged to the proximal end of the first bottom rigid connector 521, and the distal shoulder rigid connector 526 is rotatable relative to the first bottom rigid connector 521 in one direction. The proximal end of the proximal shoulder rigid connector 525 is hinged to the distal end of the second bottom rigid connector 522, and the proximal shoulder rigid connector 525 is rotatable relative to the second bottom rigid connector 522 in one direction.

[0050] like Figure 15As shown, the proximal end of the intermediate rigid connector 524 is hinged to the distal end of the proximal shoulder rigid connector 525, and the intermediate rigid connector 524 is rotatable relative to the proximal shoulder rigid connector 525 in one direction; the proximal end of the intermediate rigid connector 524 is hinged to the proximal end of the distal shoulder rigid connector 526, and the intermediate rigid connector 524 is rotatable relative to the distal shoulder rigid connector 526 in one direction. The proximal end of the inner rigid connector 527 is hinged to the distal end of the third bottom rigid connector 523, and the inner rigid connector 527 is rotatable relative to the third bottom rigid connector 523 in one direction; the distal end of the inner rigid connector 527 is hinged to the distal shoulder rigid connector 526, and the inner rigid connector 527 is rotatable relative to the distal shoulder rigid connector 526 in one direction. The internal rigid connector 527 is mainly used to adjust the opening angle of the distal shoulder rigid connector 526 and the proximal shoulder rigid connector 525 to be consistent, so that the intermediate rigid connector 524 can open horizontally.

[0051] In alternative embodiments, the hinged support bracket 520 is not limited to the above-mentioned combination of seven rigid connectors, as long as the multiple rigid connectors of the hinged support bracket 520 can expand radially outward under force.

[0052] like Figures 13 to 16 As shown, when the inner tube 100 and the head tube 300 are fixed in position and the outer tube 200 is subjected to an axial force toward the distal end, the outer tube 200 drives the second bottom rigid connector 522 and the third bottom rigid connector 523 to move distally, thereby driving the proximal shoulder rigid connector 525 and the inner rigid connector 527 to open synchronously, and further driving the intermediate rigid connector 524 and the distal shoulder rigid connector 526 to lift. Through the combined action of the distal shoulder rigid connector 526 and the proximal shoulder rigid connector 525, the intermediate rigid connector 524 can expand radially outward relative to the outer tube 200. After expansion, the intermediate rigid connector 524 can perform dilation treatment on the inner wall of the blood vessel.

[0053] like Figure 16 As shown, in some embodiments, all rigid connectors in the hinged support bracket 520 have arc-shaped cross-sections to better fit the outer wall of the inner tube 100, the outer wall of the outer tube 200, or the outer wall of the rigid connector located on the inside.

[0054] like Figure 16 As shown, the intermediate rigid connector 524, proximal shoulder rigid connector 525, and distal shoulder rigid connector 526 of the articulated support stent 520 can be designed to be of different lengths to accommodate diseased blood vessels with different stenosis diameters and stenosis lengths.

[0055] like Figure 16 and Figure 17As shown, the first bottom rigid connector 521, the second bottom rigid connector 522, and the third bottom rigid connector 523 have the same structure. One end of the first bottom rigid connector 521 has an outwardly protruding first limiting platform 5211, and the end of the first limiting platform 5211 has a first limiting step surface 5211a. One end of the second bottom rigid connector 522 has an outwardly protruding second limiting platform, and the end of the second limiting platform has a second limiting step surface. One end of the third bottom rigid connector 523 has an outwardly protruding third limiting platform, and the end of the third limiting platform has a third limiting step surface.

[0056] like Figure 18 and Figure 19 As shown, the intermediate rigid connector 524 has concave fourth limiting grooves 5241 at both ends, and a fourth limiting step surface 5241a at the bottom of the fourth limiting grooves 5241. The cross-section of the intermediate rigid connector 524 is arc-shaped. A pressure focusing protrusion 530 for cutting or compressing plaques is formed on the side of the intermediate rigid connector 524 facing away from the inner tube 100. The cross-section of the pressure focusing protrusion 530 is trapezoidal or triangular; the pressure focusing protrusion 530 can better cut or compress severely calcified lesions within the blood vessel. Combined with... Figure 15 and Figure 16 The length direction of the intermediate rigid connector 524 is parallel to the axial direction of the outer tube 200, and the length direction of the external pressure focusing protrusion 530 of the intermediate rigid connector 524 is also parallel to the axial direction of the outer tube 200. When the articulated support stent 520 expands radially outward, the linear intermediate rigid connector 524 and the pressure focusing protrusion 530 together compress the inner wall of the blood vessel. Compared with the arched strip connector in Embodiment 1, the intermediate rigid connector 524 has a larger compression area on the inner wall of the blood vessel, resulting in a better therapeutic effect on the expansion of the inner wall of the blood vessel.

[0057] like Figure 20 As shown, one end of the proximal shoulder rigid connector 525 is provided with an outwardly protruding fifth limiting platform 5251, and the end of the fifth limiting platform 5251 is provided with a fifth limiting step surface. The other end of the proximal shoulder rigid connector 525 is provided with an inwardly recessed fifth limiting groove 5252, and the end of the fifth limiting groove 5252 is provided with a fifth groove limiting step surface.

[0058] like Figure 21 As shown, one end of the distal shoulder rigid connector 526 is provided with an outwardly protruding sixth limiting platform 5261, and the end of the sixth limiting platform 5261 is provided with a sixth limiting step surface. The other end of the distal shoulder rigid connector 526 is provided with an inwardly recessed sixth limiting groove 5262, and the end of the sixth limiting groove 5262 is provided with a sixth groove limiting step surface.

[0059] like Figure 22As shown, the internal rigid connector 527 has a recessed seventh limiting groove 5271 at both ends, and one of the seventh limiting grooves 5271 has a seventh groove limiting step surface at its end.

[0060] Combination Figure 16 , Figure 17 and Figure 21 As shown, the first limiting platform 5211 of the first bottom rigid connector 521 and the sixth limiting groove 5262 of the distal shoulder rigid connector 526 are shaped to match. The first limiting step surface 5211a at the end of the first limiting platform 5211 and the sixth limiting step surface at the end of the sixth limiting groove 5262 are in a concave-convex fit to restrict the distal shoulder rigid connector 526 to rotate only in one direction relative to the first bottom rigid connector 521.

[0061] Combination Figure 16 , Figure 17 and Figure 20 As shown, the second limiting platform of the second bottom rigid connector 522 and the fifth limiting groove 5252 of the proximal shoulder rigid connector 525 are shaped to match. The second limiting step surface at the end of the second limiting platform and the fifth limiting step surface at the end of the fifth limiting groove 5252 are in concave-convex fit to restrict the proximal shoulder rigid connector 525 to rotate only in one direction relative to the second bottom rigid connector 522.

[0062] Combination Figure 16 , Figure 18 and Figure 20 As shown, the fifth limiting platform 5251 of the proximal shoulder rigid connector 525 and one of the fourth limiting grooves 5241 of the intermediate rigid connector 524 are shaped to match. The fifth limiting step surface at the end of the fifth limiting platform 5251 and the fourth limiting step surface 5241a at the end of one of the fourth limiting grooves 5241 engage in a concave-convex fit to restrict the proximal shoulder rigid connector 525 to rotate relative to the intermediate rigid connector 524 in only one direction. The fifth limiting platform of the distal shoulder rigid connector 526 is also hinged to the seventh limiting groove 5271 of the same internal rigid connector 527.

[0063] Combination Figure 16 , Figure 18 and Figure 21 As shown, the sixth limiting platform 5261 of the distal shoulder rigid connector 526 and the fourth limiting groove 5241 of the intermediate rigid connector 524 are shaped to match. The sixth limiting step surface at the end of the sixth limiting platform 5261 and the fourth groove limiting step surface 5241a at the end of the fourth limiting groove 5241 are in a concave-convex fit to restrict the distal shoulder rigid connector 526 to rotate only in one direction relative to the intermediate rigid connector 524.

[0064] Combination Figure 16 and Figure 22 As shown, the third limiting platform of the third bottom rigid connector 523 and one of the seventh limiting grooves 5271 of the internal rigid connector 527 are shaped to match. The third limiting step surface at the end of the third limiting platform and the seventh groove limiting step surface at the end of one of the seventh limiting grooves 5271 are in concave-convex fit to restrict the internal rigid connector 527 to rotate only in one direction relative to the third bottom rigid connector 523.

[0065] like Figures 16 to 22 As shown, in all rigid connectors of the hinged support bracket 520, the groove sidewall of the limiting groove in all rigid connectors is provided with a hemispherical groove, and the opposite sides of the limiting platform in all rigid connectors are provided with outwardly protruding hemispherical bosses. The hemispherical bosses and the hemispherical grooves are spherically matched so that the rigid connector with the limiting groove can rotate relative to the rigid connector with the limiting platform.

[0066] The dilation catheter provided in Embodiment 2 of the present invention, when dilating the inner wall of a blood vessel, involves holding the handle 400 and pushing the outer tube pusher 420 distally. The outer tube pusher 420 drives the outer tube 200 distally. Since the position of the inner tube 100 is fixed at this time, and the second bottom rigid connector 522 and the third bottom rigid connector 523 of the hinged support 520 are fixedly connected to the outer tube 200, the outer tube 200 drives the second bottom rigid connector 522 and the third bottom rigid connector 523 distally. The bottom rigid connector 522 compresses the proximal shoulder rigid connector 525, and the third bottom rigid connector 523 compresses the inner rigid connector 527. The proximal shoulder rigid connector 525 and the inner rigid connector 527 simultaneously open outwards, further lifting the intermediate rigid connector 524 and the distal shoulder rigid connector 526. This allows the intermediate rigid connector 524 to expand radially outwards relative to the outer tube 200, enabling it to dilate the inner wall of the blood vessel. In actual operation, the displacement of the outer tube pusher 420 can control the articulated stent 520 to achieve different degrees of expansion, and the diameter of the articulated stent 520 in its expanded state can be adjusted to meet the clinical needs for dilation treatment of different stenotic blood vessels.

[0067] In summary, the dilation catheter provided by this invention features a radial dilation component at the distal end of the outer tube 200, capable of radially expanding outward relative to the outer tube 200. This radial dilation component includes multiple radial dilation elements arranged axially at intervals around the distal end of the inner tube 100 and possessing a deformable structure. When the outer tube 200 is subjected to an axial force towards the distal end, the multiple radial dilation elements of the radial dilation component expand radially outward, thereby dilating the vascular wall. This dilation catheter eliminates the need for balloon dilation, completely avoiding damage to the blood vessel caused by excessive balloon inflation and rupture, resulting in better surgical safety. Furthermore, it eliminates the need for manual operation of a pressure pump to control the balloon inflation pressure, reducing the operational difficulty of the vascular dilation surgery and lowering the technical requirements for the operator. Moreover, the pressure focusing protrusion 530 on the side of the radial dilation element facing away from the inner tube 100 further improves the dilation treatment effect on vascular wall plaques.

[0068] Obviously, the above embodiments are merely illustrative examples for clear explanation and are not intended to limit the implementation. Those skilled in the art will recognize that other variations or modifications can be made based on the above description. It is neither necessary nor possible to exhaustively list all possible implementations here. However, obvious variations or modifications derived therefrom are still within the scope of protection of this invention.

Claims

1. A dilation catheter, characterized in that, It includes an inner tube (100), an outer tube (200), a head end tube (300), and a radial expansion assembly (500); the inner tube (100) passes through the inner cavity of the outer tube (200), the distal end of the inner tube (100) extends outward from the distal opening of the outer tube (200), and the head end tube (300) is located at the distal end of the outer tube (200) and is fixedly connected to the inner tube (100); The radial expansion assembly (500) is a deformable structure capable of radially expanding outward relative to the outer tube (200). The radial expansion assembly (500) includes a plurality of radial expansion elements arranged circumferentially around the inner tube (100). The proximal ends of the plurality of radial expansion elements are connected to the outer tube (200), and the distal ends of the plurality of radial expansion elements are connected to the head end tube (300) or the inner tube (100). When the inner tube (100) is fixed in position and the outer tube (200) is subjected to an axial force toward the distal end, the plurality of radial expansion elements of the radial expansion assembly (500) expand radially outward, and after expansion, the plurality of radial expansion elements can expand the inner wall of the blood vessel.

2. The dilation catheter according to claim 1, characterized in that, The radial expansion element is a strip-shaped connector (510) that is long and can undergo elastic bending deformation in its middle when subjected to force. The proximal end of the strip-shaped connector (510) is fixedly connected to the distal end of the outer tube (200), and the distal end of the strip-shaped connector (510) is fixedly connected to the proximal end of the head tube (300).

3. The dilation catheter according to claim 2, characterized in that, The strip connector (510) is formed, either as a portion of the inner tube (100) or as an integral part of the strip connector (510), as a pressure focusing protrusion (530) for cutting or squeezing the patch.

4. The dilation catheter according to claim 2, characterized in that, The strip connector (510) is a straight strip connector (510a) with equal width at all points along the axial direction; or, The strip connector (510) is a gradually flared strip connector (510b) with a width that gradually increases from the middle to both ends; or, The strip connector (510) is a multi-step flared strip connector (510c) whose width increases progressively from the middle to both ends.

5. The dilation catheter according to claim 2, characterized in that, The strip connector (510) is provided with a plurality of developing marks (511) arranged at intervals along its own length.

6. The dilation catheter according to claim 1, characterized in that, The radial expansion element is a hinged support bracket (520) composed of multiple rigid connectors hinged together. When the hinged support bracket (520) is subjected to force, each rigid connector rotates relative to the hinge point to change the angle between the rigid connectors, thereby realizing the radial expansion of the hinged support bracket (520) relative to the outer tube (200).

7. The dilation catheter according to claim 6, characterized in that, The articulated support bracket (520) includes a first bottom rigid connector (521), a second bottom rigid connector (522), a third bottom rigid connector (523), a middle rigid connector (524), a proximal shoulder rigid connector (525), a distal shoulder rigid connector (526), ​​and an internal rigid connector (527). The first bottom rigid connector (521) is fixed to the inner tube (100), the second bottom rigid connector (522) is fixed to the outer tube (200), and the third bottom rigid connector (523) is fixed to the outer tube (200) and located between the first bottom rigid connector (521) and the second bottom rigid connector (522). The proximal end of the proximal shoulder rigid connector (525) is hinged to the second bottom rigid connector (522), the distal end of the distal shoulder rigid connector (526) is hinged to the first bottom rigid connector (521), the proximal end of the intermediate rigid connector (524) is hinged to the distal end of the proximal shoulder rigid connector (525), and the proximal end of the intermediate rigid connector (524) is hinged to the proximal end of the distal shoulder rigid connector (526). The proximal end of the internal rigid connector (527) is hinged to the third bottom rigid connector (523), and the distal end of the internal rigid connector (527) is hinged to the distal shoulder rigid connector (526).

8. The dilation catheter according to claim 7, characterized in that, The intermediate rigid connector (524) has a pressure focusing protrusion (530) on the side opposite to the inner tube (100) for cutting or squeezing patches.

9. The dilation catheter according to claim 7, characterized in that, In the hinged support bracket (520), one of the two rigid connecting members that are hinged to each other is provided with a limiting groove, and the other is provided with a limiting platform that cooperates with the limiting groove. A limiting step surface that cooperates with the limiting platform and the limiting groove is provided. The limiting step surface is used to restrict the rigid connecting member with the limiting groove to rotate only on one side of the other rigid connecting member that is hinged to each other.

10. The dilation catheter according to any one of claims 1-9, characterized in that, The dilation catheter also includes a handle (400) and a sealing and limiting ring (600); the proximal ends of the inner tube (100) and the outer tube (200) are both connected to the handle (400), and the handle (400) is provided with an outer tube pusher (420) for applying axial force to the outer tube (200); the sealing and limiting ring (600) is fixedly connected to the inside of the outer tube (200) and movably sleeved on the outer periphery of the inner tube (100).

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