Intravascular catheter and laser ablation catheter system

Abstract

The present application provides an intravascular catheter and a laser ablation catheter system, the intravascular catheter comprising a distal tube body and a fiber bundle; the distal tube body has a receiving cavity arranged in an axial eccentric manner, the distal tube body forms a thin cavity wall and a thick cavity wall in a radial opposite arrangement around the receiving cavity, and the cavity wall connected between the thin cavity wall and the thick cavity wall smoothly transitions in thickness; the fiber bundle is arranged in the receiving cavity and is arranged near the thin cavity wall in the axial eccentric manner of the receiving cavity. In this way, the receiving cavity is arranged eccentrically, the thick cavity wall provides support against radial collapse, avoiding the collapse of the distal tube body when bending; the thin cavity wall can reduce the bending resistance, so that the distal tube body is oriented to bend towards the side of the thin cavity wall, reducing or avoiding the occurrence of twisting and S-bending. The fiber bundle is arranged eccentrically in the receiving cavity and bends synchronously with the distal tube body, ensuring that the light output direction of the fiber bundle is consistent with the bending direction, and improving the stability of laser transmission.

Description

Technical Field

[0001] This invention relates to the field of medical device technology, and in particular to an intravascular catheter and laser ablation catheter system. Background Technology

[0002] Currently, interventional coronary laser ablation technology has become an important means of treating complex coronary artery lesions. Its core principle is to transmit laser to the lesion site through a coronary laser ablation catheter, and use the laser to precisely ablate plaque in the blood vessel and restore vascular patency.

[0003] Existing coronary laser ablation catheters mostly employ a single material and uniform rigidity design, with a predominantly symmetrical wall thickness cross-section and fiber bundles directly attached to the inner wall. As clinical demands increase, the treatment of complex coronary artery lesions (such as severely tortuous vessels, CTO lesions, and left circumflex artery lesions) is becoming increasingly challenging, placing higher demands on the catheter's bending ability, flexibility, and delivery stability. Existing coronary laser ablation catheters have gradually revealed numerous compatibility issues in clinical applications, and their structural design is no longer sufficient to meet the treatment needs of complex lesions. These issues are mainly manifested in insufficient bending ability, poor flexibility, and susceptibility of laser transmission to bending. Radial collapse and axial twisting easily occur during bending, affecting the catheter's structural stability and laser transmission accuracy. The direct attachment of the fiber bundle to the catheter wall also results in compression during bending, further impacting bending performance and laser transmission effectiveness. Summary of the Invention

[0004] The purpose of this invention is to provide an intravascular catheter and a laser ablation catheter system to solve the problems of poor bending performance and easy influence of bending on laser transmission in existing laser ablation catheters.

[0005] To solve the above-mentioned technical problems, the present invention provides an intravascular catheter, which includes a distal tube body and an optical fiber bundle;

[0006] The distal tube has an eccentrically arranged cavity along the axial direction. The distal tube forms a thin cavity wall and a thick cavity wall arranged radially opposite to each other around the cavity. The cavity wall connecting the thin cavity wall and the thick cavity wall has a smooth transition in thickness.

[0007] The optical fiber bundle passes through the accommodating cavity and is eccentrically arranged along the axial direction of the accommodating cavity on one side close to the thin cavity wall.

[0008] Optionally, the distal tube body includes a guide head section, a joint section, and a support section along the axial direction from the distal end to the proximal end; the material stiffness of the guide head section, the joint section, and the support section increases sequentially.

[0009] Optionally, the axial length of the guide head section is 8 mm to 10 mm, the axial length of the joint section is 12 mm to 15 mm, and the axial length of the support section is 20 mm to 25 mm; the guide head section and the joint section are integrally formed or hot-melt connected, and the joint section and the support section are hot-melt connected.

[0010] Optionally, the intravascular catheter includes a constraint wing for constraining the fiber bundle, one end of which is integrally formed and connected to the cavity wall of the receiving cavity, and the connection is located on the side close to the thin cavity wall; the other end of the constraint wing extends toward the interior of the receiving cavity.

[0011] Optionally, the intravascular catheter includes two constraint wings, which are symmetrically distributed about the line connecting the thin lumen wall and the thick lumen wall, to constrain the optical fiber bundle between the two constraint wings.

[0012] Optionally, the constraint wing extends axially along the accommodating cavity and bends in the cross-sectional direction of the accommodating cavity, concave towards the fiber bundle.

[0013] Optionally, the intravascular catheter includes a flexible filler adhesive, which is injected into the receiving cavity to fill the space between the fiber bundle and the cavity wall.

[0014] Optionally, the intravascular catheter further includes an intermediate tube connected to the proximal end of the distal tube body; the distal tube body has a guidewire lumen, the distal portion of which is located within the receiving cavity and extends along the axis of the distal tube body; the proximal portion of which extends laterally from the connection between the distal tube body and the intermediate tube body and opens.

[0015] Optionally, the fiber bundle is located between the thin cavity wall and the guide wire cavity in the cross-sectional direction of the accommodating cavity; there is a gap between the fiber bundle and the cavity wall of the accommodating cavity.

[0016] To address the aforementioned technical problems, the present invention also provides a laser ablation catheter system, which includes an intravascular catheter as described above, and a laser; the proximal end of the intravascular catheter is connected to the laser; and the fiber bundle extends along the axial direction of the intravascular catheter to the proximal end.

[0017] In summary, in the intravascular catheter and laser ablation catheter system provided by the present invention, the intravascular catheter includes a distal tube body and an optical fiber bundle; the distal tube body has a receiving cavity arranged eccentrically along the axial direction, and the distal tube body forms a thin cavity wall and a thick cavity wall arranged radially opposite to each other around the receiving cavity, with the cavity wall connecting the thin cavity wall and the thick cavity wall having a smooth transition in thickness; the optical fiber bundle passes through the receiving cavity and is arranged eccentrically along the axial direction of the receiving cavity on the side close to the thin cavity wall.

[0018] This configuration, by eccentrically arranging the accommodating cavity, utilizes the thick cavity wall to provide support against radial collapse, preventing the distal tube from collapsing during bending. The thin cavity wall reduces bending resistance, causing the distal tube to bend directionally towards the thinner cavity wall, reducing or eliminating twisting and S-bends, resulting in a smooth and controllable bending trajectory and improved bending compliance. Furthermore, the fiber bundle is eccentrically positioned within the accommodating cavity near the thinner cavity wall, bending synchronously with the distal tube, ensuring that the fiber bundle's output direction aligns with the bending direction of the distal tube, thus enhancing laser transmission stability. Attached Figure Description

[0019] Those skilled in the art will understand that the accompanying drawings are provided to better understand the invention and do not constitute any limitation on the scope of the invention.

[0020] Figure 1 This is a schematic diagram of an intravascular catheter according to an embodiment of the present invention.

[0021] Figure 2 This is a schematic diagram of a distal portion of an intravascular catheter according to an embodiment of the present invention.

[0022] Figure 3 This is a schematic cross-sectional view of the distal tube body according to an embodiment of the present invention.

[0023] In the attached diagram: 1-distal tube; 10-accommodating cavity; 11-cavity wall; 11a-thin cavity wall; 11b-thick cavity wall; 12-guide head section; 13-joint section; 14-support section; 15-guide wire cavity; 2-intermediate tube; 3-proximal connector; 4-fiber bundle; 5-constraint wing; 6-flexible filler adhesive. Detailed Implementation

[0024] To make the objectives, advantages, and features of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. It should be noted that the drawings are all in a very simplified form and are not drawn to scale, and are only used to facilitate and clarify the explanation of the embodiments of this invention. Furthermore, the structures shown in the drawings are often part of the actual structures. In particular, different figures may emphasize different aspects and may sometimes use different scales.

[0025] As used herein, the singular forms “a,” “an,” “one,” and “the” include plural objects; the term “or” is generally used to mean “and / or”; the term “a number” is generally used to mean “at least one”; and the term “at least two” is generally used to mean “two or more”. Furthermore, the terms “first,” “second,” and “third” are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined as “first,” “second,” or “third” may explicitly or implicitly include one or at least two of that feature; “one end” and “the other end,” and “proximal end” and “distal end” generally refer to two corresponding portions, which include not only the endpoints. The terms “proximal end” and “distal end” are defined herein in relation to an intravascular catheter having an end for insertion into the human body and a control end extending outside the body. The term "proximal" refers to the position closer to the manipulatory end of the intravascular catheter protruding outside the body, and the term "distal" refers to the position closer to the end of the intravascular catheter inserted into the body and therefore further away from the manipulatory end. Optionally, in manual or hand-operated applications, the terms "proximal" and "distal" are defined herein relative to the operator, such as a surgeon or clinician. The term "proximal" refers to the position closer to the operator, and the term "distal" refers to the position closer to the patient's affected area and therefore further away from the operator. Furthermore, as used in this invention, "installed," "connected," "attached," or "set" of one element on another should be interpreted broadly, generally indicating only a connection, coupling, cooperation, or transmission relationship between the two elements, which can be direct or indirect through an intermediate element, and should not be construed as indicating or implying a spatial positional relationship between the two elements, i.e., one element can be located inside, outside, above, below, or to one side of the other element, unless otherwise explicitly stated. Those skilled in the art will understand the specific meaning of the above terms in this invention according to the specific circumstances. Furthermore, directional terms such as above, below, up, down, upward, downward, left, right, etc., are used relative to exemplary embodiments as they are shown in the figures, with upward or up direction pointing towards the top of the corresponding figure, and downward or down direction pointing towards the bottom of the corresponding figure.

[0026] The purpose of this invention is to provide an intravascular catheter and a laser ablation catheter system to solve the problems of poor bending performance and easy influence of bending on laser transmission in existing laser ablation catheters. The following description refers to the accompanying drawings.

[0027] Please refer to Figures 1 to 3 This invention provides an intravascular catheter, comprising a distal end ( Figure 1 and Figure 2(left end) to proximal end ( Figure 1 and Figure 2 The distal tube 1, intermediate tube 2, and proximal connector 3 are sequentially connected at the right end of the tube. The distal tube 1 is used for interventional vascularization, while the proximal connector 3 is used for connection to an external laser. In one example, the axial length of the distal tube 1 is 40mm~50mm, and the axial length of the intermediate tube 2 is 2000mm~3000mm.

[0028] The intravascular catheter also includes an optical fiber bundle 4; the distal tube body 1 has a receiving cavity 10 arranged eccentrically along the axial direction, and the distal tube body 1 forms a thin cavity wall 11a and a thick cavity wall 11b arranged radially opposite to each other around the receiving cavity 10, and the cavity wall 11 connecting the thin cavity wall 11a and the thick cavity wall 11b has a smooth transition in thickness; the optical fiber bundle 4 passes through the receiving cavity 10 and is arranged eccentrically along the axial direction of the receiving cavity 10 on the side close to the thin cavity wall 11a.

[0029] The inventors discovered that many existing laser ablation catheters employ a symmetrical wall thickness design in their cross-section. While this design ensures uniform stress distribution when the catheter is straight, it can lead to radial collapse and axial twisting when the catheter enters a tortuous blood vessel or bends. This reduces the structural stability of the catheter, hindering the transmission of pushing force and making precise control of the catheter's trajectory difficult, thus increasing the complexity of the procedure. Furthermore, it can compress the internal fiber bundle, causing it to shift. This can result in decreased laser transmission efficiency and a deviation in the light emission direction, making it impossible to accurately target the lesion. This not only affects the ablation effect but may also damage surrounding healthy blood vessels, increasing the risk of postoperative complications.

[0030] Therefore, in this embodiment, the endovascular catheter has an eccentrically positioned lumen 10. Thus, for the distal tube body 1, the lumen wall 11 of the lumen 10 is not a uniformly thick cross-section with asymmetrical wall thickness, but rather exhibits a shape where some parts of the lumen wall 11 are thinner (thin lumen wall 11a) and some parts are thicker (thick lumen wall 11b). The transition between the thin lumen wall 11a and the thick lumen wall 11b is smooth, without obvious steps, avoiding stress concentration.

[0031] This configuration utilizes the thick cavity wall 11b to provide support against radial collapse, preventing the distal tube 1 from collapsing during bending. The thin cavity wall 11a reduces bending resistance, allowing the distal tube 1 to bend directionally towards the thin cavity wall 11a, reducing or avoiding twisting and S-bends. The bending trajectory is smooth and controllable, improving bending compliance. Furthermore, due to the improved structural stability of the distal tube 1, and with the fiber bundle 4 eccentrically positioned in the accommodating cavity 10 near the thin cavity wall 11a, bending synchronously with the distal tube 1, the light output direction of the fiber bundle 4 is consistent with the bending direction of the distal tube 1. This effectively reduces the compression of the fiber bundle 4 inside the accommodating cavity 10 caused by the bending of the distal tube 1, reducing or avoiding displacement of the fiber bundle 4 and improving laser output stability.

[0032] The distal tube 1 comprises a guide section 12, a joint section 13, and a support section 14 along the axial direction from the distal end to the proximal end; the material stiffness of the guide section 12, the joint section 13, and the support section 14 increases sequentially. It should be noted that the guide section 12, the joint section 13, and the support section 14 are distinguished by the material and stiffness of the cavity wall 11 of the distal tube 1 in the axial direction, and the cross-sectional structural shape of the guide section 12, the joint section 13, and the support section 14 can be consistent.

[0033] Further research by the inventors revealed that some existing intravascular catheters, if the distal end is too soft, lack sufficient pushing force and cannot smoothly pass through dense plaques or CTO lesions, easily leading to problems such as jamming or failure to reach the correct position. Conversely, if the distal end is too hard, it lacks flexibility, easily protruding against the vessel wall during pushing, causing damage such as scratches or tears to the vascular intima, increasing surgical risks. Some intravascular catheters may also have an unreasonable rigidity design, leading to stress concentration during bending, resulting in the risk of twisting or kinking.

[0034] In this embodiment, the distal tube 1 adopts a three-segment continuous variable stiffness design, with the stiffness gradually changing from soft to hard from the distal end to the proximal end, without any steps or abrupt changes. In one embodiment, the axial length of the guide head 12 is 8 mm to 10 mm, and its material can be high-elasticity biocompatible polyurethane or medical-grade silicone, characterized by being extremely soft, hydrophilic, and without support. The function of the guide head 12 is to explore and adhere to the vessel wall, smoothly entering the tortuous section of the blood vessel and avoiding damage to the vascular intima. Optionally, the inner wall of the distal end of the guide head 12 is printed with a 1 mm to 2 mm wide band of contrast-enhancing ink, which serves as a positioning tool during surgery.

[0035] The axial length of the joint segment 13 is 12 mm to 15 mm. Its material can be a medium-elasticity polymer, such as thermoplastic elastomer (TPE), characterized by its ability to easily bend in the eccentrically arranged accommodating cavity 10, good flexibility, and strong fatigue resistance. The function of the joint segment 13 is to act as a "joint" of the distal tube body 1, adaptively bending according to the vessel morphology to achieve smooth bending and transmit part of the pushing force. Optionally, the joint segment 13 has an annular groove inside.

[0036] The axial length of the support section 14 is 20 mm to 25 mm. Its material can be a semi-rigid polymer, such as polycarbonate (PC), which is characterized by moderate rigidity, can provide stable axial pushing force, and has good torsional resistance. The function of the support section 14 is to connect the joint section 13 and the intermediate tube 2, ensuring that it does not bend during pushing, that the force is transmitted smoothly, and that the distal tube 1 and the intermediate tube 2 do not become disengaged.

[0037] Optionally, the guide head section 12 and the joint section 13 are integrally formed or thermally fused together, and the joint section 13 is thermally fused together with the support section 14. The guide head section 12, the joint section 13, and the support section 14 work together to solve the defects of unreasonable rigidity design of existing intravascular catheters, while taking into account guidance, bending, and pushing force, which helps to achieve high flexibility in bending and provides a basic condition for the stability of the fiber bundle 4.

[0038] Optionally, the intravascular catheter includes a restraining wing 5 for constraining the fiber bundle 4. Optionally, the restraining wing 5 extends axially along the receiving cavity 10, with its axial extension length consistent with the axial length of the distal tube body 1. In the cross-sectional direction, one end of the restraining wing 5 is integrally formed and connected to the cavity wall 11 of the receiving cavity 10, with the connection point located near the thin cavity wall 11a; the other end of the restraining wing 5 extends toward the interior of the receiving cavity 10. Further, the intravascular catheter includes a flexible filler 6 (such as medical silicone or medical flexible adhesive), which is injected into the receiving cavity 10 to fill the space between the fiber bundle 4 and the cavity wall 11 of the receiving cavity 10.

[0039] The functions of the constraint wing 5 mainly include the following aspects: First, it forms a coplanar constraint on the fiber bundle 4, ensuring that all fibers within the fiber bundle 4 maintain the same light output plane and preventing twisting, warping, or misalignment of the fibers in the fiber bundle 4; second, it forms a directional constraint on the fiber bundle 4, ensuring that the fiber bundle 4 is always located on the side close to the thin cavity wall 11a (i.e., the lesion plaque side), ensuring precise laser directional ablation; third, it limits the fiber displacement of the fibers in the fiber bundle 4, preventing the fibers from bending laterally and sticking to the cavity wall 11 when the distal tube 1 bends; fourth, in conjunction with the filling of the flexible filler adhesive 6, it enables the fibers in the fiber bundle 4 to achieve suspension buffering, making the entire distal tube 1 structurally integrated, ensuring that the fiber bundle 4 bends synchronously with the distal tube 1, thereby ensuring the stability of the light output direction of the fiber bundle 4 and ensuring smooth laser transmission.

[0040] Preferably, the intravascular catheter includes two constraint wings 5, which are symmetrically distributed about line A connecting the thin cavity wall 11a and the thick cavity wall 11b, to constrain the fiber bundle 4 between the two constraint wings 5. Further, the constraint wings 5 ​​are curved in the cross-sectional direction of the accommodating cavity 10, concave towards the fiber bundle 4. In one example, the constraint wing 5 is an arc-shaped elastic structure, its material being the same as the material of the cavity wall 11 corresponding to its axial direction, and preferably integrally formed. Taking the axial section of the guide head segment 12 corresponding to the constraint wing 5 as an example, it uses the same material as the guide head segment 12 and is integrally formed with the cavity wall 11 of the guide head segment 12; the axial sections of the joint segment 13 and the support segment 14 corresponding to the constraint wing 5 are similarly formed. Preferably, the spacing between the two constraint wings 5 ​​matches the cross-sectional size of the fiber bundle 4, and a small gap is maintained between the constraint wings 5 ​​and the optical fibers of the fiber bundle 4, allowing only the optical fibers to be arranged in the same plane, forcing the light outlets of each optical fiber to maintain a coplanar orientation, and preventing the optical fibers from twisting, warping, or shifting. Preferably, the two constraint wings 5 ​​present a semi-encircling and limiting shape for the fiber bundle 4, so that there is a gap between the fiber bundle 4 and the cavity wall 11 of the accommodating cavity 10 (mainly the thin cavity wall 11a side), so that the fiber does not directly contact the cavity wall 11, but forms a suspension buffer by filling with flexible filler 6.

[0041] In the accommodating cavity 10, the gaps between the constraining wings 5 ​​and the optical fibers of the fiber bundle 4, the space outside the constraining wings 5, and all other remaining cavities inside the accommodating cavity 10 are filled and cured with flexible filler 6. With this configuration, when the distal tube 1 bends, the distal end of the fiber bundle 4 can float slightly and automatically make way under the wrapping of the flexible filler 6, reducing or avoiding pushing against the cavity wall 11, while not increasing the rigidity of the distal tube 1 and avoiding compression of the optical fibers.

[0042] Optionally, the distal tube 1 has a guidewire lumen 15, the distal portion of which is located within the receiving cavity 10 and extends along the axis of the distal tube 1; the proximal portion of which extends laterally from the connection between the distal tube 1 and the intermediate tube 2 and opens. In this embodiment, the guidewire lumen 15 is a distally open guidewire lumen, which does not need to extend along the intermediate tube 2 to a proximal external opening, facilitating rapid replacement of the guidewire and intravascular catheter. The lumen wall of the guidewire lumen 15 can be made of materials such as polytetrafluoroethylene (PTFE) to reduce friction between the guidewire and the lumen wall. Understandably, although the distal portion of the guidewire lumen 15 is also located within the receiving cavity 10, it is not filled with flexible filler 6 to facilitate guidewire insertion. The flexible filler 6 fills the outer side of the guidewire lumen 15, thereby fixing the guidewire lumen 15 at the center of the distal tube 1. The fiber bundle 4 is located between the thin cavity wall 11a and the guide wire cavity 15 in the cross-sectional direction of the accommodating cavity 10.

[0043] This invention also provides a laser ablation catheter system, which includes an intravascular catheter as described above, and a laser (not shown); the proximal end of the intravascular catheter is connected to the laser; the fiber bundle 4 extends along the axial direction of the intravascular catheter to the proximal end. Please refer to the references. Figure 1 In an alternative example, the intermediate tube 2 of the intravascular catheter is made of flexible nylon or medium-hardness Pebax, with a wall thickness of 0.10 mm to 0.15 mm. An axial fiber optic channel is axially routed through the intermediate tube 2 to allow the fiber optic bundle 4 to extend through it. The intermediate tube 2 is thermally fused to the proximal end of the distal tube 1 (i.e., the proximal end of the support segment 14). Furthermore, the fiber optic bundle 4 extends along the axial direction of the intravascular catheter through the fiber optic channel of the intermediate tube 2 to the proximal end, and is connected to the laser via a proximal connector 3. In one example, the proximal connector 3 is inserted into the corresponding interface of the laser, allowing the laser emitted by the laser to be transmitted to the distal end via the fiber optic bundle 4.

[0044] In summary, in the endovascular catheter and laser ablation catheter system provided by this invention, the endovascular catheter includes a distal tube body and an optical fiber bundle. The distal tube body has a receiving cavity arranged eccentrically along the axial direction. The distal tube body forms a thin cavity wall and a thick cavity wall arranged radially opposite to each other around the receiving cavity, and the cavity wall connecting the thin cavity wall and the thick cavity wall has a smooth transition in thickness. The optical fiber bundle passes through the receiving cavity and is arranged eccentrically along the axial direction of the receiving cavity, close to the side of the thin cavity wall. With this configuration, by eccentrically arranging the receiving cavity, the thick cavity wall provides support against radial collapse, preventing the distal tube body from collapsing when bending. The thin cavity wall reduces bending resistance, allowing the distal tube body to bend directionally towards the thin cavity wall side, reducing or avoiding twisting and S-bends, resulting in a smooth and controllable bending trajectory and improved bending flexibility. Furthermore, the fiber bundle is eccentrically positioned on one side of the cavity near the thin cavity wall, and bends synchronously with the distal tube, ensuring that the light output direction of the fiber bundle is consistent with the bending direction of the distal tube, thereby improving the stability of laser transmission.

[0045] The intravascular catheter and laser ablation catheter system provided in this embodiment significantly reduces the minimum bending radius compared to existing intravascular catheters, allowing for easy passage through complex vascular sites such as tortuous coronary arteries, left circumflex arteries, and CTO lesions, thus greatly improving the clinical surgical success rate. Through a three-segment variable stiffness design, an eccentric cavity wall design, and a fiber optic suspension design, the flexibility of the distal tube 1 is significantly improved, making it smoother to push and less likely to abut against the vessel wall, greatly reducing surgical risks. The distal tube 1 is less prone to collapse, twisting, or kinking when bent, facilitating precise control of the intravascular catheter's trajectory and reducing the difficulty of surgical procedures. The fiber optic suspension design prevents the fiber from being squeezed or displaced when the distal tube 1 bends, ensuring laser transmission efficiency, enabling precise plaque ablation, reducing damage to normal vascular tissue, and improving surgical outcomes. Combined with the coplanar limiting effect of the constraint wings 5 ​​and the filling of flexible filler adhesive 6, the orientation of the fiber bundle 4 is locked, ensuring that all fibers are always on the same light-emitting plane, avoiding light emission disorder caused by fiber twisting or warping, further improving ablation accuracy. Meanwhile, the optical fiber has no direct contact with the cavity wall 11, which reduces the wear of the optical fiber and extends the service life of the intravascular catheter.

[0046] It should be noted that the above embodiments can be combined with each other. The above description is only a description of preferred embodiments of the present invention and is not intended to limit the scope of the present invention in any way. Any changes or modifications made by those skilled in the art based on the above disclosure shall fall within the protection scope of the present invention.

Claims

1. An intravascular catheter, characterized in that, Includes the distal tube and fiber bundle; The distal tube has an eccentrically arranged cavity along the axial direction. The distal tube forms a thin cavity wall and a thick cavity wall arranged radially opposite to each other around the cavity. The cavity wall connecting the thin cavity wall and the thick cavity wall has a smooth transition in thickness. The optical fiber bundle passes through the accommodating cavity and is eccentrically arranged along the axial direction of the accommodating cavity on one side close to the thin cavity wall.

2. The intravascular catheter according to claim 1, characterized in that, The distal tube body includes a guide head section, a joint section, and a support section along the axial direction from the distal end to the proximal end; the material stiffness of the guide head section, the joint section, and the support section increases sequentially.

3. The intravascular catheter according to claim 2, characterized in that, The axial length of the guide head section is 8 mm to 10 mm, the axial length of the joint section is 12 mm to 15 mm, and the axial length of the support section is 20 mm to 25 mm; the guide head section and the joint section are integrally formed or hot-melt connected, and the joint section and the support section are hot-melt connected.

4. The intravascular catheter according to claim 1, characterized in that, The intravascular catheter includes a constraint wing for constraining the fiber bundle. One end of the constraint wing is integrally formed and connected to the cavity wall of the receiving cavity, and the connection is located on the side close to the thin cavity wall. The other end of the constraint wing extends toward the interior of the receiving cavity.

5. The intravascular catheter according to claim 4, characterized in that, The intravascular catheter includes two constraint wings, which are symmetrically distributed about the line connecting the thin lumen wall and the thick lumen wall, for constraining the optical fiber bundle between the two constraint wings.

6. The intravascular catheter according to claim 4, characterized in that, The constraint wing extends axially along the accommodating cavity and bends in the cross-sectional direction of the accommodating cavity, concave towards the fiber bundle.

7. The intravascular catheter according to claim 1, characterized in that, The intravascular catheter includes a flexible filler adhesive, which is injected into the receiving cavity to fill the space between the optical fiber bundle and the cavity wall.

8. The intravascular catheter according to claim 1, characterized in that, The intravascular catheter also includes an intermediate tube connected to the proximal end of the distal tube body; the distal tube body has a guidewire lumen, the distal portion of which is located within the receiving lumen and extends along the axis of the distal tube body; the proximal portion of which extends laterally from the connection between the distal tube body and the intermediate tube body and opens.

9. The intravascular catheter according to claim 8, characterized in that, The optical fiber bundle is located between the thin cavity wall and the guide wire cavity in the cross-sectional direction of the accommodating cavity; there is a gap between the optical fiber bundle and the cavity wall of the accommodating cavity.

10. A laser ablation catheter system, characterized in that, The intravascular catheter includes any one of claims 1 to 9, and further includes a laser; the proximal end of the intravascular catheter is connected to the laser; the fiber bundle extends along the axial direction of the intravascular catheter to the proximal end.

Images