Balloon catheter and cryoablation system

Abstract

The utility model relates to a balloon catheter and a cryoablation system. The balloon catheter comprises an outer tube, an inner tube, a balloon, a pull wire and a handle. The inner tube is sleeved with the outer tube, and the far end of the outer tube is fixedly connected with the near end of the balloon. The far end part of the inner tube is exposed out of the outer tube, and the far end of the inner tube is fixedly connected with the far end of the balloon; an air inlet cavity and an air return cavity which are respectively communicated with fluid of the balloon are arranged between the inner tube and the outer tube; the far end of the pull wire is fixed to the far end of the balloon, the near end of the pull wire extends out of the body, and the pull wire is used for controlling bending deformation of the balloon; the handle is connected to the near end of the outer tube and provided with an air inlet connector and an air return connector which are communicated with the air inlet cavity and the air return cavity respectively. The bending degree of the balloon can be adjusted through the pull wire, the balloon can be suitable for being attached to blood vessel walls of various shapes, and blood flow cannot be blocked.

Description

Technical Field

[0001] The present application belongs to the field of medical devices, and specifically relates to a balloon catheter and a cryoablation system. Background Art

[0002] The pulmonary artery is a blood vessel that carries blood from the heart to the lungs. Pulmonary hypertension (PH) is a chronic cardiovascular disease characterized by abnormally elevated pulmonary artery blood pressure (hypertension), which leads to changes in the patient's cardiopulmonary circulation hemodynamics, pulmonary artery vascular remodeling, right heart hypertrophy, and functional failure. The gold standard for the diagnosis of PH is a mean pulmonary artery pressure of ≥25 mmHg measured by right cardiac catheter at sea level and at rest, with a pulmonary artery wedge pressure of ≤15 mmHg and a pulmonary vascular resistance of >3 Wood units. Experimental data have shown that PH is associated with increased sympathetic nerve excitability around the pulmonary artery and abnormal activity of pulmonary artery baroreceptors. Blocking the sympathetic nerves around the pulmonary artery or permanently destroying the structure and function of the baroreceptors can reduce pulmonary artery pressure, which will become a breakthrough technology for the treatment of PH, such as pulmonary artery denervation (PADN), which is a method for reducing pulmonary vascular sympathetic nerve stimulation. Studies have shown that patients with PH have shown symptoms such as increased plasma norepinephrine levels, increased muscle sympathetic nerve excitability, and increased vascular sympathetic nerve endings. Therefore, the neurohormonal axis has been recognized as a potential therapeutic target. The principle of PADN is to use energy ablation to block the sympathetic nerves in the pulmonary vascular endothelium, thereby reducing pulmonary artery pressure and delaying disease progression. This minimally invasive interventional technique will provide a new means for interventional treatment of pulmonary hypertension.

[0003] In existing pulmonary artery denervation surgery using cryoablation, cryogenic energy is usually generated by spraying a cryogenic medium inside a balloon, causing the balloon to expand and adhere to the tissue. Therefore, traditional cryoballoons can block blood flow during ablation, especially in the main pulmonary artery, which can be life-threatening in severe cases.

[0004] For example: The patent application number is CN201911251793.3, and the patent name is a Chinese patent for a cryoballoon catheter for the treatment of clinical pulmonary hypertension. It mentions a catheter with an open circular balloon design at the distal end. After the balloon is inflated, it becomes a ring shape, and the blood flow inside it passes smoothly.

[0005] Some other patents propose to form multiple through-passages inside the balloon to allow blood to flow through, which will result in many nodes in the balloon catheter, which is difficult to achieve in actual processing.

[0006] Although the prior art provides a balloon design solution to avoid blood flow obstruction, it has the following main disadvantages:

[0007] 1. The adjustment is not flexible enough. After the balloon is expanded, it can only present a preset shape, which is difficult to adapt to the irregular lesion site;

[0008] 2. The feasibility is not high. The balloon catheter has many nodes, which is difficult to achieve in actual processing. Summary of the invention

[0009] Based on this, it is necessary to provide a balloon catheter and cryoablation system to address the problem that the balloon can only present a preset shape after expansion and is difficult to achieve in actual processing.

[0010] On one hand, the present application provides a balloon catheter, comprising: an outer tube, an inner tube, a balloon, a pull wire and a handle; the outer tube is sleeved outside the inner tube, and the distal end of the outer tube is fixedly connected to the proximal end of the balloon; the distal end of the inner tube partially exposes the outer tube, and the distal end of the inner tube is fixedly connected to the distal end of the balloon; wherein an air inlet cavity and an air return cavity respectively connected to the balloon fluid are arranged between the inner tube and the outer tube;

[0011] The distal end of the pull wire is fixed to the distal end of the balloon, and the proximal end of the pull wire extends out of the body, and the pull wire is used to control the bending deformation of the balloon;

[0012] The handle is connected to the proximal end of the outer tube, and is provided with an air inlet joint and an air return joint. The air inlet joint is communicated with the air inlet cavity, and the air return joint is communicated with the air return cavity.

[0013] In an optional embodiment, the balloon catheter further includes: a bending adjustment wire, the bending adjustment wire is located in the tube wall of the outer tube, the distal end of the bending adjustment wire is fixedly connected to the distal end of the outer tube, and the proximal end of the bending adjustment wire is connected to the handle.

[0014] In an optional embodiment, the outer tube has a pull wire cavity, and the pull wire extends from the pull wire cavity out of the body.

[0015] In an optional embodiment, a circular hole communicating with the pull wire cavity is provided on the distal end of the outer tube or the outer wall of the distal end portion of the outer tube, and the proximal end of the pull wire enters the pull wire cavity from the circular hole and extends out of the body.

[0016] In an optional embodiment, the balloon catheter further comprises a sheath tube, wherein the sheath tube is sleeved on the outside of the outer tube, and the pull wire extends out of the body from a gap between the sheath tube and the outer tube.

[0017] In an optional embodiment, a collar is fixed on the tube wall of the distal end portion of the outer tube, and the pull wire passes through the collar and extends out of the body.

[0018] In an optional embodiment, a pull ring is fixed on the tube wall of the distal end portion of the outer tube, and the pull wire passes through the pull ring and extends out of the body.

[0019] In an optional embodiment, the pull wire is one of nickel-titanium wire, stainless steel wire or polymer fiber braided wire.

[0020] On the other hand, an embodiment of the present application provides a cryoablation system, including a cryoablation device and the above-mentioned balloon catheter, wherein the balloon catheter is connected to the cryoablation device via a connector, and is used to deliver the refrigerant in the cryoablation device to the balloon via the air inlet connector, and perform cryoablation.

[0021] In an optional embodiment, the cryoablation system further includes: a bending adjustment wire, the bending adjustment wire is located in the tube wall of the outer tube, the distal end of the bending adjustment wire is fixedly connected to the distal end of the outer tube, and the proximal end of the bending adjustment wire is connected to the handle.

[0022] Compared with the prior art, the advantages of the embodiments of the present application are:

[0023] 1. In the embodiment of the present application, the distal end of the pull wire is fixed together with the distal end of the balloon. The balloon is bent and deformed under the action of the pull wire traction force. The outer side of the balloon is in an arc-shaped surface and is in contact with the tissue. The curvature of the balloon can be controlled by adjusting the pull wire traction force, so that the balloon can be in contact with various irregular shapes and different sizes of blood vessel walls, improving the fit and ablation efficiency. The inner side forms an arc-shaped gap for blood flow to pass through and avoid blocking blood flow.

[0024] 2. The bending deformation of the balloon can be controlled by fixing a pull wire at the distal end of the balloon, which is very easy to implement and process. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 This is a schematic structural diagram of a balloon catheter according to one embodiment of the present application;

[0026] Figure 2 This is a schematic diagram of a balloon catheter in one embodiment of the present application being attached to the wall of a blood vessel tissue;

[0027] Figure 3 This is a schematic cross-sectional view of an outer tube according to an embodiment of the present application;

[0028] Figure 4 This is a schematic diagram of a balloon bending when a circular hole is located at the distal end of an outer tube according to an embodiment of the present application;

[0029] Figure 5 A top view of a balloon when a circular hole is located at the distal end of an outer tube according to an embodiment of the present application;

[0030] Figure 6 This is a schematic structural diagram of a balloon catheter with a sheath according to an embodiment of the present application;

[0031] Figure 7 This is a schematic structural diagram of a balloon catheter with a collar according to an embodiment of the present application;

[0032] Figure 8 This is a schematic structural diagram of a balloon catheter with a pull ring according to an embodiment of the present application;

[0033] Fig. 9 This is a schematic diagram of the state of a balloon catheter when a bending wire and a pull wire are used together to adjust the bending according to one embodiment of the present application;

[0034] Fig.10 A schematic diagram of a cryoablation system according to an embodiment of the present application. DETAILED DESCRIPTION

[0035] In order to make the above-mentioned purposes, features and advantages of the present application more obvious and easy to understand, the specific implementation methods of the present application are described in detail below in conjunction with the accompanying drawings. In the following description, many specific details are set forth to facilitate a full understanding of the present application. However, the present application can be implemented in many other ways different from those described herein, and those skilled in the art can make similar improvements without violating the connotation of the present application, so the present application is not limited by the specific embodiments disclosed below.

[0036] In the description of the present application, it should be understood that if the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc. appear, the orientation or position relationship indicated by these terms is based on the orientation or position relationship shown in the accompanying drawings, which is only for the convenience of describing the present application and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present application.

[0037] In addition, if the terms "first" or "second" appear, these terms are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include at least one of the features. In the description of this application, if the term "plurality" appears, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0038] In this application, unless otherwise clearly specified and limited, if the terms "installed", "connected", "connected", "fixed" and the like appear, these terms should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integrated connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to the specific circumstances.

[0039] In the present application, unless otherwise clearly specified and limited, if there is a description that a first feature is "above" or "below" a second feature, etc., or similar descriptions appear, it may mean that the first and second features are in direct contact, or that the first and second features are in indirect contact through an intermediate medium. Moreover, the first feature being "above", "above" and "above" the second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. The first feature being "below", "below" and "below" the second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

[0040] It should be noted that if an element is referred to as being "fixed to" or "disposed on" another element, it may be directly on the other element or there may be a central element. If an element is considered to be "connected to" another element, it may be directly connected to the other element or there may be a central element at the same time. If any, the terms "vertical", "horizontal", "upper", "lower", "left", "right" and similar expressions used in this application are for illustrative purposes only and do not represent the only implementation method.

[0041] The technical solution provided by the embodiments of the present application is described below in conjunction with the accompanying drawings.

[0042] The proximal end mentioned in the present application refers to the end close to the surgical operator, and the distal end refers to the end far away from the surgical operator.

[0043] like Figure 1 and Figure 2As shown, the present application provides a balloon catheter 100, comprising: an outer tube 1, an inner tube 2, a balloon 3, a pull wire 4 and a handle 5; the outer tube 1 is sleeved on the outside of the inner tube 2, and the distal end of the outer tube 1 is fixedly connected to the proximal end of the balloon 3; the distal end portion of the inner tube 2 is exposed from the outer tube 1, and the distal end of the inner tube 2 is fixedly connected to the distal end of the balloon 3; wherein, an air inlet cavity 6 and an air return cavity 7 which are respectively connected to the fluid of the balloon 3 are arranged between the inner tube 2 and the outer tube 1; the distal end of the pull wire 4 is fixed to the distal end of the balloon 3, and the proximal end of the pull wire 4 extends out of the body, and the pull wire 4 is used to control the bending deformation of the balloon 3; the handle 5 is connected to the proximal end of the outer tube 1, and the handle 5 is provided with an air inlet connector 51 and an air return connector 52, the air inlet connector 51 is connected to the air inlet cavity 6, and the air return connector 52 is connected to the air return cavity 7.

[0044] In the embodiment of the present application, the air inlet connector 51 and the air return connector 52 on the handle 5 are both connected to the cryoablation device to deliver refrigerant to the ablation catheter or recover the refrigerant. The refrigerant in the cryoablation device enters the air inlet cavity 6 through the air inlet connector 51, and then enters the balloon 3 through the air inlet cavity 6, filling and expanding the balloon 3, and the freezing energy is released in the balloon 3, thereby achieving ablation of the target position. After the ablation is completed, the refrigerant in the balloon 3 enters the recovery device of the cryoablation device through the air return cavity 7 and the air return connector 52, and the refrigerant is recovered to form a cold source circuit. In this embodiment, the distal end of the pull wire 4 can be fixed to the distal end of the balloon 3 by welding, gluing, etc., and the proximal end of the pull wire 4 extends out of the body. Before performing the ablation operation, the pull wire 4 can be pulled to adjust the curvature of the balloon 3 to better fit the blood vessel wall, such as Figure 2 Preferably, a wire pull knob may also be provided on the handle 5, and when the curvature of the balloon 3 needs to be adjusted, the wire pull knob can be turned.

[0045] In this embodiment, the distal end of the pull wire 4 is fixed together with the distal end of the balloon 3. When the pull wire 4 is pulled, the balloon 3 bends and deforms under the action of the traction force of the pull wire 4. The outer side of the balloon 3 is an arc-shaped surface that is in contact with the tissue. The curvature of the balloon 3 can be controlled by adjusting the magnitude of the traction force of the pull wire 4, so that the balloon 3 can be in contact with various irregular shapes and blood vessel walls of different sizes to improve the fit and ablation efficiency. An arc-shaped gap is formed on the inner side for blood flow to pass through and avoid blocking blood flow. In addition, a pull wire 4 is fixedly connected to the distal end of the balloon 3 to control the bending deformation of the balloon 3, which is very easy to implement and easy to process.

[0046] In order to better limit the position of the pull wire 4, in one embodiment, a pull wire cavity 11 can be provided on the outer tube 1, referring to Figure 3 The wire drawing cavity 11 may be a cavity opened on the wall of the outer tube 1, or may be a separate pipeline. Figure 31 shows the situation of the wire pulling cavity 11 opened on the tube wall of the outer tube 1. The wire pulling cavity 11 is located in the wire pulling cavity 11 and extends out of the body from the wire pulling cavity 11. This can avoid damaging the blood vessel when the wire pulling cavity 11 is pulled.

[0047] Furthermore, a circular hole 12 connected to the wire-pulling cavity 11 can be provided at the distal end of the outer tube 1 or on the outer wall of the distal part of the outer tube 1, and the proximal end of the wire 4 enters the wire-pulling cavity 11 from the circular hole 12 and extends out of the body. Specifically, the curvature of the balloon 3 when being pulled is related to the position of the circular hole 12. For example, when the circular hole 12 is located at the distal end of the outer tube 1, that is, the wire-pulling cavity 11 runs through the entire outer tube 1, in this case, the balloon 3 can be bent into a circle when being pulled, such as Figure 4 and Figure 5 When the circular hole 12 is located on the outer wall of the distal end of the outer tube 1, the wire drawing cavity 11 penetrates part of the outer tube 1, and the balloon 3 can be bent into an arc when being pulled, as shown in FIG. Figure 1 and Figure 2 as shown in .

[0048] In another optional embodiment, the balloon catheter 100 further includes a sheath tube 13, such as Figure 6 The sheath tube 13 is sleeved on the outside of the outer tube 1, and the pull wire 4 extends out of the body from the gap between the sheath tube 13 and the outer tube 1. The sheath tube 13 can be provided to limit the pull wire 4 to avoid damaging the blood vessel when the pull wire 4 is pulled.

[0049] In another optional embodiment, a collar 14 is fixed on the tube wall of the distal end portion of the outer tube 1, such as Figure 7 As shown, the pull wire 4 passes through the ring 14 and extends out of the body. The ring 14 is provided to limit the pull wire 4 to avoid damaging the blood vessel when the pull wire 4 is pulled.

[0050] In another optional embodiment, a pull ring 15 is fixed on the tube wall of the distal end of the outer tube 1. Figure 8 As shown, the pull wire 4 passes through the pull ring 15 and extends out of the body. The pull ring 15 can also limit the pull wire 4, and the size is smaller, saving the volume of the catheter.

[0051] The material of the pull wire 4 can be a thin, soft metal wire with small elastic deformation when stretched, such as nickel-titanium wire, stainless steel wire, etc., or a polymer fiber braided wire, such as nylon, aramid, Kuraray fiber braided wire, etc., so as to achieve traction of the distal end of the balloon 3, and then achieve efficient bending of the balloon 3.

[0052] In a preferred embodiment, the balloon catheter 100 may further include a bending adjustment wire (not shown in the figure), which is located in the wall of the outer tube 1, and the distal end of the bending adjustment wire is fixedly connected to the distal end of the outer tube 1, and the proximal end of the bending adjustment wire is connected to the handle 5. By setting the bending adjustment wire, the curvature of the outer tube 1 can be adjusted, and the bending of the balloon 3 can be adjusted at various angles in combination with the pull wire 4, so as to be applicable to more application scenarios. When the bending adjustment wire and the pull wire 8 are adjusted together, the structure of the balloon catheter 100 is referred to as Fig. 9 More preferably, a bending knob may be provided on the handle 5, which makes the bending operation more convenient.

[0053] The present application also provides a cryoablation system, including a cryoablation device 200 and the above-mentioned balloon catheter 100, Fig.10 , the balloon catheter 100 is connected to the cryoablation device 200 through the connector 300, and is used to deliver the refrigerant in the cryoablation device 200 to the balloon 3 through the air inlet connector 51, and perform cryoablation. Specifically, in this embodiment, the cryoablation device 200 includes a human-machine interaction module 201, a control module 202, and an air circuit module 203. The human-machine interaction module 201 is electrically connected to the control module 202, and the control module 202 is electrically connected to the air circuit module 203. The air circuit module 203 can be connected to the handle 5 of the cryoablation catheter 100 through the connector 300. Specifically, the air circuit module 203 is respectively connected to the air inlet connector 51 and the air return connector 52 on the handle 5 through the connector 300, and is used to deliver refrigerant to the ablation catheter 100 or recover refrigerant. During the operation, the cryoablation device 200 is first started, the balloon catheter 100 is operated to enter the patient's body, and then the control module 202 controls the gas circuit module 203 to start delivering refrigerant to the balloon catheter 100. After the balloon 3 is filled with refrigerant, it is deployed in the patient's body. The pull line 4 is pulled to adjust the curvature of the balloon 3, so that the balloon 3 is close to the lesion, and then the ablation operation is started. The ablation parameters are returned to the control module 202, processed by the control module 202 and finally fed back to the human-computer interaction module 201. After the ablation is completed, the control module 202 is operated to make the gas circuit module 203 stop delivering the refrigerant.

[0054] The above is an exemplary description of the cryoablation system. In actual applications, the cryoablation device 200 may also adopt other technical means in the prior art, which will not be described in detail here.

[0055] Preferably, the cryoablation system further comprises: a bending adjustment wire (not shown in the figure), which is located in the tube wall of the outer tube 1, the distal end of the bending adjustment wire is fixedly connected to the distal end of the outer tube 1, and the proximal end of the bending adjustment wire is connected to the handle 5.

[0056] Finally, it should be noted that the above is only a preferred embodiment of the present application and is not intended to limit the present application. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present application should be included in the scope of protection of the present application.

Claims

1. A balloon catheter, characterized in that: include: An outer tube, an inner tube, a balloon, a pull line and a handle; the outer tube is sleeved outside the inner tube, and the distal end of the outer tube is fixedly connected to the proximal end of the balloon; the distal end of the inner tube partially exposes the outer tube, and the distal end of the inner tube is fixedly connected to the distal end of the balloon; wherein an air inlet cavity and an air return cavity are respectively connected to the balloon fluid between the inner tube and the outer tube; The distal end of the pull wire is fixed to the distal end of the balloon, and the proximal end of the pull wire extends out of the body, and the pull wire is used to control the bending deformation of the balloon; The handle is connected to the proximal end of the outer tube, and is provided with an air inlet joint and an air return joint. The air inlet joint is communicated with the air inlet cavity, and the air return joint is communicated with the air return cavity.

2. The balloon catheter according to claim 1, characterized in that: The balloon catheter further includes: a bending adjustment wire, which is located in the tube wall of the outer tube, the distal end of the bending adjustment wire is fixedly connected to the distal end of the outer tube, and the proximal end of the bending adjustment wire is connected to the handle.

3. The balloon catheter according to claim 1, characterized in that: The outer tube has a pull wire cavity, and the pull wire extends out of the body from the pull wire cavity.

4. The balloon catheter according to claim 3, characterized in that: A circular hole communicating with the pull-wire cavity is provided on the distal end of the outer tube or the outer wall of the distal end portion of the outer tube, and the proximal end of the pull-wire enters the pull-wire cavity from the circular hole and extends out of the body.

5. The balloon catheter according to claim 1, characterized in that: The balloon catheter further comprises a sheath tube, wherein the sheath tube is sleeved on the outside of the outer tube, and the pull wire extends out of the body from a gap between the sheath tube and the outer tube.

6. The balloon catheter according to claim 1, characterized in that: A collar is fixed on the tube wall of the distal end of the outer tube, and the pull wire passes through the collar and extends out of the body.

7. The balloon catheter according to claim 1, characterized in that: A pull ring is fixed on the tube wall of the distal end portion of the outer tube, and the pull wire passes through the pull ring and extends out of the body.

8. The balloon catheter according to claim 1, characterized in that: The pull wire is one of nickel-titanium wire, stainless steel wire or polymer fiber braided wire.

9. A cryoablation system, characterized in that: It comprises a cryoablation device and a balloon catheter as described in any one of claims 1 to 8, wherein the balloon catheter is connected to the cryoablation device via a joint, and is used to deliver the refrigerant in the cryoablation device to the balloon via the air inlet joint, and perform cryoablation.

10. The cryoablation system according to claim 9, characterized in that: The cryoablation system further includes: a bending adjustment wire, which is located in the tube wall of the outer tube, the distal end of the bending adjustment wire is fixedly connected to the distal end of the outer tube, and the proximal end of the bending adjustment wire is connected to the handle.

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