Interventional catheter

Abstract

The present application relates to an intervention catheter, which comprises a catheter body, a pressure sensor, a memory wire, a controller, the memory wire has a starting phase transition temperature and an ending phase transition temperature; the memory wire is electrically connected with the controller, when the pressure sensor signal detected by the controller is greater than a first pressure setting value, the controller reduces the current output to the memory wire to reduce the temperature of the memory wire, and then the hardness of the memory wire is reduced. The present application can actively adjust the hardness of the catheter according to the needs of the operation, and reduce the damage to the human body cavity.

Description

Technical Field

[0001] The present invention relates to a medical device, in particular to a catheter used for intervention in human body cavities such as the digestive tract and blood vessels. Background Art

[0002] Interventional catheters are typically used during interventional procedures in the digestive tract, blood vessels, and other body cavities to deliver medications or other surgical components through their hollow working channels, such as stents for cardiac surgery. Traditional catheters cannot balance the flexibility required to navigate narrow vessels or the digestive tract with the support required for lesions. For example, braided nickel-titanium alloy catheters have a consistent hardness, making them susceptible to torque transmission failure when navigating curved vessels or the digestive tract. Furthermore, the physician relies on experience to determine the contact pressure between the catheter and the vessel or digestive tract wall. Improper handling can lead to excessive pressure from the catheter contacting the vessel or digestive tract wall, potentially damaging the endothelium. This is particularly true during cardiac surgery, where the beating heart causes the catheter near the heart to follow the heartbeat within the blood vessels. Inappropriate compatibility of the catheter's hardness and shape with the blood vessels can further damage the endothelium. During digestive tract treatments, peristaltic movements can lead to inappropriate compatibility between the digestive tract and the catheter's shape.

[0003] WO2020199233A1 discloses a needle system and method for transcatheter cardiac ventricular septal puncture. When the needle temperature is above its phase transition temperature, the tip of the needle exhibits a smooth bend and increases in hardness. When the needle temperature is below its phase transition temperature, the needle becomes less flexible and less hard. During surgery, when the needle is inserted into the patient's ventricle, the patient's body temperature is used to raise the tip of the needle above its phase transition temperature, resulting in a memorized, smooth bend and increased hardness, thus facilitating ventricular septal puncture. However, this needle cannot actively adjust its hardness based on the physician's needs. Summary of the Invention

[0004] The object of the present invention is to provide an interventional catheter, the hardness of which can be actively adjusted according to the needs of the operation.

[0005] The technical solution of the present invention is:

[0006] An interventional catheter comprising:

[0007] A catheter body, wherein the center of the catheter body has an axially extending working channel;

[0008] A pressure sensor for generating a pressure sensing signal, wherein the pressure sensor is disposed on or adjacent to the outer surface of the catheter body;

[0009] a sensing signal line embedded in the catheter body, the sensing signal line being electrically connected to the pressure sensor, and the sensing signal line being electrically connected to a controller for receiving a pressure sensing signal;

[0010] A memory metal wire is embedded in the catheter body, the memory metal wire having a low starting phase transition temperature and a high ending phase transition temperature, the starting phase transition temperature and the ending phase transition temperature forming a phase transition temperature range of the memory metal wire. Within the phase transition temperature range, the hardness of the memory metal wire gradually increases with increasing temperature. The memory metal wire is electrically connected to a controller for providing current, and when the controller outputs current to the memory metal wire, the memory metal wire generates heat.

[0011] The controller reduces the current output to the memory wire to lower the temperature of the memory wire when the pressure sensing signal detected by the controller is greater than the first pressure setting value. The lowered temperature is within the phase change temperature range, thereby reducing the hardness of the memory wire.

[0012] Another technical solution is:

[0013] An interventional catheter comprising:

[0014] At least two sections of a catheter body connected directly or indirectly, wherein the center of the catheter body has an axially extending working channel;

[0015] A pressure sensor for generating a pressure sensing signal, wherein the pressure sensors are respectively arranged on the outer surface of the at least two sections of the catheter body or adjacent to the outer surface thereof;

[0016] a sensing signal line embedded in the catheter body, the sensing signal line being electrically connected to each of the pressure sensors, and the sensing signal line being electrically connected to a controller for receiving pressure sensing signals;

[0017] Memory metal wires are respectively embedded in the at least two sections of the catheter body, each section of the memory metal wire having a different or the same low starting phase transition temperature and a different or the same high ending phase transition temperature. The starting phase transition temperature and the ending phase transition temperature form a phase transition temperature range for each section of the memory metal wire. Within the phase transition temperature range, as the temperature rises, the hardness of the corresponding section of the memory metal wire gradually increases. Each section of the memory metal wire is electrically connected to a controller for providing current. When the controller outputs current to each section of the memory metal wire, the corresponding section of the memory metal wire generates heat.

[0018] The controller controls the output current of each segment of the memory metal wire respectively. When the controller detects that the pressure sensing signal of the corresponding segment is greater than the first pressure setting value, the controller reduces the current output to the corresponding segment of the memory metal wire to lower the temperature of the segment of the memory metal wire. The lowered temperature is within the phase change temperature range of the segment of the memory metal wire, thereby reducing the hardness of the segment of the memory metal wire.

[0019] Furthermore, when the pressure sensing signal detected by the controller is less than the second pressure setting value, the controller increases the current output to the memory metal wire to increase the temperature of the memory metal wire. The increased temperature is within the phase change temperature range, thereby increasing the hardness of the memory metal wire.

[0020] Furthermore, a temperature sensor is embedded in the catheter body, which is used to detect the temperature of the catheter body and generate a temperature sensing signal. The temperature sensor is electrically connected to the controller through the sensing signal line; when the controller detects that the temperature sensing signal is higher than the first temperature setting value, the controller reduces the current output to the memory metal wire to lower the temperature of the memory metal wire.

[0021] Furthermore, when the controller detects that the temperature sensing signal is lower than the second temperature setting value, the controller increases the current output to the memory metal wire to increase the temperature of the memory metal wire.

[0022] Furthermore, the memory metal wire is embedded in the catheter body in a spiral shape.

[0023] Compared with the prior art, the present invention has the following advantages:

[0024] When the catheter is advanced or advanced through a human body cavity, the patient's body temperature exceeds the low-value initial phase transition temperature of the memory wire, rendering the catheter soft and easily traversable through curved human cavities. When traversing a curved human cavity or reaching a lesion, the controller transmits current to the memory wire to raise its temperature, allowing it to enter the phase transition temperature range and increase its hardness, making it easier to traverse the curved human cavity or to take shape within the lesion, facilitating the delivery of medication or surgical instruments within the catheter's working channel. When the controller detects that the pressure sensor signal is greater than a first set pressure value, indicating that the catheter is applying pressure exceeding a safe value to the human cavity, the controller reduces the current output to the memory wire to lower the temperature of that section of the memory wire, thereby reducing its hardness and ensuring the safety of the interventional procedure. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Attachment Figure 1 This is a schematic diagram of the structure of the present invention with a handle;

[0026] Attachment Figure 2 is a front view of the catheter of the present invention;

[0027] Attachment Figure 3 For attachment Figure 2 AA direction cross-sectional view;

[0028] Attachment Figure 4 For attachment Figure 3 Enlarged view of point B;

[0029] Attachment Figure 5 This is a schematic diagram of the present invention with a handle, wherein the catheter is fixed in a human body cavity, such as a blood vessel;

[0030] Attachment Figure 6 A circuit block diagram of the present invention;

[0031] Attachment Figure 7 is the control flow block diagram of the controller; where:

[0032] 1. Catheter body; 2. Working channel; 3. Power cord; 4. Sensing signal line; 5. Pressure sensor; 6. Controller; 7. Memory wire; 8. Temperature sensor; 9. Three-way valve; 10. Control button; 11. Handle; 12. First section of catheter body; 13. Second section of catheter body; 14. Stainless steel braided wire; 15. First section of memory wire; 16. Second section of memory wire; 17. First section of pressure sensor; 18. Second section of pressure sensor; 19. First section of temperature sensor; 20. Second section of temperature sensor; 21. Human cavity (blood vessel); 22. Thermal insulation layer; 23. Lining layer. DETAILED DESCRIPTION

[0033] See also Figure 1 The present invention is provided with a handle 11. The handle 11 is provided with a control button 10 for starting and stopping the controller 6, or for selecting a program or parameter. The sensing signal line 4 and the power line 3 for supplying power to the memory wire 7 are connected to the controller 6. The three-way valve 9 is used to deliver drugs into the working channel 2 of the catheter. Figure 2 The front view of the interventional catheter is shown. The catheter body 1 is made of a transparent material, such as polyamide (nylon), Pebax (polyether block amide), etc., and has soft and electrically insulating properties. A stainless steel braided wire 14 is embedded in the catheter body 1 at the proximal end of the catheter (close to the operating physician). The catheter body 1 at the distal end of the catheter (away from the operating physician) has two directly connected sections, namely a first section of the catheter body 12 and a second section of the catheter body 13. The two sections of the catheter body 1 are respectively provided with a first section of memory wire 15 and a second section of memory wire 16. The controller 6 uses a control chip such as a PLC (programmable logic controller). Its program control logic can be found in the attached figure. Figure 7The control flow chart of FIG. 1 is as follows: the controller 6 is electrically connected to the memory wire 7 through the power line 3 to provide current to the memory wire 7; the temperature sensor 8 and the pressure sensor 5 are as shown in FIG. Figure 6 The circuit block diagram is connected to the controller 6 via a sensor signal line 4. The memory wire 7 is made of nickel-titanium alloy. The inner wall of the working channel 2 in the center of the catheter body 1 is provided with an inner lining layer 23 made of PTFE, which has a low coefficient of friction. A thermal insulation layer 22 made of PI material is placed closely to the outside of the inner lining layer 23 to isolate heat from the catheter body 1 and the cavity of the working channel 2.

[0034] See also Figure 3 and Figure 4 In the first embodiment, if the first and second memory wires 15, 16 are connected in series and powered by the controller 6 via the power line 3, the first and second memory wires 15, 16 have the same heating temperature under the premise of the same resistance, and the hardness of the first and second catheter bodies 12, 13 of the first embodiment remains consistent. Referring to the drawings, the interventional catheter includes:

[0035] A catheter body 1 having an axially extending working channel 2 at its center for delivering drugs or surgical instruments through the working channel 2;

[0036] A pressure sensor 5 is used to detect a pressure sensing signal exerted by the catheter body 1 on a human cavity, such as the inner wall of a blood vessel. The pressure sensor is disposed on or near the outer surface of the catheter body to accurately sense the pressure borne by the catheter body 1.

[0037] A sensing signal line 4 is embedded in the catheter body 1 and electrically connected to the pressure sensor 5. The sensing signal line 4 is also electrically connected to a controller 6 for receiving a pressure sensing signal.

[0038] A memory wire 7 is embedded in the catheter body 1. The memory wire 7 has a low initial phase transition temperature (e.g., 40°C) and a high final phase transition temperature (45°C). The initial and final phase transition temperatures define a phase transition temperature range for the memory wire 7. Within this phase transition temperature range, the hardness of the memory wire 7 gradually increases as the temperature rises. The initial and final phase transition temperatures can be controlled by customizing the composition of the nickel-titanium alloy. The memory wire 7 is electrically connected to a controller 6 for providing current via a power line 3. When the controller 6 outputs current to the memory wire 7, the memory wire generates heat.

[0039] Controller 6, when the pressure sensor signal detected by controller 6 is greater than a first pressure setting value (the first pressure setting value is the maximum pressure value that the human body cavity, such as the blood vessel or digestive tract, can withstand, and is set to not damage the human body cavity), controller 6 reduces the current output to memory wire 7 to lower the temperature of memory wire 7. The lowered temperature falls within the phase transition temperature range, thereby reducing the hardness of memory wire 7. The catheter becomes more flexible and can better adapt to the shape of a human body cavity with large angles. When the pressure sensor signal detected by controller 6 is less than a second pressure setting value (the second pressure setting value is less than the first pressure setting value, and the pressure range formed by the second pressure setting value and the first pressure setting value is a reasonable pressure range that the human body cavity can withstand), controller 6 increases the current output to memory wire 7 to raise the temperature of memory wire 7. The raised temperature falls within the phase transition temperature range, causing the hardness of memory wire 7 to harden as the temperature increases within the phase transition temperature range, thereby allowing the memory wire 7 to have a better shape and better adapt to the human body cavity.

[0040] A temperature sensor 8 is also embedded in the catheter body 1. The temperature sensor 8 is used to detect the temperature of the catheter body 1 and generate a temperature sensing signal. The temperature sensor 8 is electrically connected to the controller 6 via the sensing signal line 4. When the controller 6 detects that the temperature sensing signal is higher than the first temperature setting value (for example, 43°C, which is the upper limit of the temperature that the human body cavity can withstand), the controller 6 reduces the current output to the memory wire 7 to lower the temperature of the memory wire. When the controller 6 detects that the temperature sensing signal is lower than the second temperature setting value (for example, 38°C, which is the lower limit of the reasonable temperature during interventional treatment of the human body cavity), the controller 6 increases the current output to the memory wire 7 to increase the temperature of the memory wire 7. Figure 2 As shown, the memory metal wire 7 is embedded in the catheter body 1 in a spiral shape, which facilitates the bending and uniform heating of the catheter body 1.

[0041] See also Figure 3 and Figure 4 In the second embodiment, if the first section of memory metal wire 15 and the second section of memory metal wire 16 in the accompanying drawings are connected in parallel and are independently powered by the controller 6, when the current values ​​of the supplied power are different, the first section of memory metal wire 15 and the second section of memory metal wire 16 have different heating temperatures, and the first section of the catheter body 12 and the second section of the catheter body 13 of this second embodiment can be controlled to have different hardnesses.

[0042] See attached Figure 3 and attached Figure 4 , an interventional catheter comprising:

[0043] at least two directly or indirectly connected catheter bodies 1, the central of which has an axially extending working channel 2;

[0044] a pressure sensor 5 for generating a pressure sensing signal, which is arranged on or adjacent to the outer surface of the at least two catheter bodies 1 respectively;

[0045] a sensing signal line 4 embedded in the catheter bodies 1, which is electrically connected to the respective pressure sensor 5 and to a controller 6 for receiving the pressure sensing signal;

[0046] a memory wire 7 embedded in the at least two catheter bodies 1 respectively, each of which has a different or the same low value of starting phase transition temperature and a different or the same high value of ending phase transition temperature, which form a phase transition temperature interval of the memory wire 7, in which the hardness of the corresponding memory wire 7 gradually increases with the increase of temperature; each of the memory wires 7 is electrically connected to the controller 6 for providing current, and when the controller 6 outputs current to each of the memory wires 7, the corresponding memory wire 7 generates heat at different temperatures when receiving different currents;

[0047] a controller 6, which controls the output current of each of the memory wires 7, and when the controller 6 detects that the pressure sensing signal of the corresponding memory wire 7 is greater than a first pressure setting value, the controller 6 reduces the output current of the corresponding memory wire 7 to reduce the temperature of the memory wire, and the first pressure setting value of each of the pressure sensing signals is different to adapt to the human body cavity with different positions and curvatures, and the reduced temperature is within the phase transition temperature interval of the memory wire 7, so as to reduce the hardness of the memory wire. In this way, the first memory wire 15 and the second memory wire 16 independently receive the current output by the controller 6, and the hardness of the first catheter body 12 and the second catheter body 13 can be independently adjusted.

Claims

1. An interventional catheter, characterized in that: It includes: A catheter body, wherein the center of the catheter body has an axially extending working channel; A pressure sensor for generating a pressure sensing signal, wherein the pressure sensor is disposed on or adjacent to the outer surface of the catheter body; a sensing signal line embedded in the catheter body, the sensing signal line being electrically connected to the pressure sensor, and the sensing signal line being electrically connected to a controller for receiving a pressure sensing signal; A memory metal wire is embedded in the catheter body, the memory metal wire having a low starting phase transition temperature and a high ending phase transition temperature, the starting phase transition temperature and the ending phase transition temperature forming a phase transition temperature range of the memory metal wire. Within the phase transition temperature range, the hardness of the memory metal wire gradually increases with increasing temperature. The memory metal wire is electrically connected to a controller for providing current, and when the controller outputs current to the memory metal wire, the memory metal wire generates heat. The controller reduces the current output to the memory wire to lower the temperature of the memory wire when the pressure sensing signal detected by the controller is greater than the first pressure setting value. The lowered temperature is within the phase change temperature range, thereby reducing the hardness of the memory wire.

2. An interventional catheter, characterized in that: It includes: At least two sections of a catheter body connected directly or indirectly, wherein the center of the catheter body has an axially extending working channel; A pressure sensor for generating a pressure sensing signal, wherein the pressure sensors are respectively arranged on the outer surface of the at least two sections of the catheter body or adjacent to the outer surface thereof; a sensing signal line embedded in the catheter body, the sensing signal line being electrically connected to each of the pressure sensors, and the sensing signal line being electrically connected to a controller for receiving pressure sensing signals; Memory metal wires are respectively embedded in the at least two sections of the catheter body, each section of the memory metal wire having a different or the same low-value starting phase transition temperature and a different or the same high-value ending phase transition temperature. The starting phase transition temperature and the ending phase transition temperature form a phase transition temperature range for each section of the memory metal wire. Within the phase transition temperature range, as the temperature rises, the hardness of the corresponding section of the memory metal wire gradually increases. Each section of the memory metal wire is electrically connected to a controller for providing current. When the controller outputs current to each section of the memory metal wire, the corresponding section of the memory metal wire generates heat. The controller controls the output current of each segment of the memory metal wire respectively. When the controller detects that the pressure sensing signal of the corresponding segment is greater than the first pressure setting value, the controller reduces the current output to the corresponding segment of the memory metal wire to lower the temperature of the segment of the memory metal wire. The lowered temperature is within the phase change temperature range of the segment of the memory metal wire, thereby reducing the hardness of the segment of the memory metal wire.

3. The interventional catheter according to claim 1 or 2, characterized in that: When the pressure sensing signal detected by the controller is less than the second pressure setting value, the controller increases the current output to the memory wire to increase the temperature of the memory wire. The increased temperature is within the phase change temperature range, thereby increasing the hardness of the memory wire.

4. The interventional catheter according to claim 1 or 2, characterized in that: A temperature sensor is also embedded in the catheter body. The temperature sensor is used to detect the temperature of the catheter body and generate a temperature sensing signal. The temperature sensor is electrically connected to the controller through the sensing signal line. When the controller detects that the temperature sensing signal is higher than the first temperature setting value, the controller reduces the current output to the memory metal wire to lower the temperature of the memory metal wire.

5. The interventional catheter according to claim 4, characterized in that: When the controller detects that the temperature sensing signal is lower than the second temperature setting value, the controller increases the current output to the memory metal wire to increase the temperature of the memory metal wire.

6. The interventional catheter according to claim 1 or 2, characterized in that: The memory metal wire is embedded in the catheter body in a spiral shape.

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