Medical catheter

Abstract

The present invention provides a medical catheter, the medical catheter comprising: a catheter body, a bending wire channel is provided in the catheter body, the bending wire channel extends from the first end of the catheter body and passes through the second end face of the catheter body; a bending wire, the first end of the bending wire is located in the catheter body and connected to the first end of the catheter body, the second end of the bending wire passes through the bending wire channel and is located outside the catheter body; the bending wire is a shape memory alloy wire, and the first end of the bending wire is pre-shaped by heat treatment to form a bending portion; the bending degree of the first end of the catheter body can be adjusted by applying a force to the second end of the bending wire. The embodiment of the present invention solves the problem that the safety of the medical catheter is reduced due to the large traction force required when the bending degree of the medical catheter is adjusted by using the bending wire.

Description

Technical Field

[0001] The present invention relates to the technical field of medical devices, and in particular to a medical catheter. Background Art

[0002] Artificial heart valve implantation is a common method for treating valvular heart disease. Generally speaking, when implanting an artificial heart valve, a guide wire is first inserted along a designated route, and then a medical catheter equipped with an artificial valve is inserted along the guide wire and the artificial valve is released in the area of ​​the native valve, and finally the guide wire and medical catheter are withdrawn.

[0003] During the catheter's entry, it will pass through the curved or thin sections of the human body's blood vessels. In order to ensure the smooth entry of the catheter, a bending wire is usually embedded in the catheter, and the bending of the front end of the catheter is controlled by pulling the bending wire. However, due to the long length of the catheter, a large force needs to be applied when pulling the bending wire, so it is easy for the bending wire to be disconnected from the catheter or break, thereby reducing the safety of the medical catheter.

[0004] Therefore, the prior art has the problem that when using the bending wire to adjust the bending degree of the medical catheter, the required traction force is relatively large, which reduces the safety of the medical catheter. Summary of the invention

[0005] The embodiments of the present invention provide a medical catheter and a method for using the medical catheter to solve the problem that the safety of the medical catheter is reduced due to the large traction force required when the bending degree of the medical catheter is adjusted using a bending wire.

[0006] In order to achieve the above-mentioned object, in a first aspect, an embodiment of the present invention provides a medical catheter, comprising:

[0007] A catheter body, wherein a bending wire channel is provided in the catheter body, and the bending wire channel extends from the first end of the catheter body and passes through the second end surface of the catheter body;

[0008] A bending adjustment wire, wherein a first end of the bending adjustment wire is located in the catheter body and connected to the first end of the catheter body, and a second end of the bending adjustment wire passes through the bending adjustment wire channel and is located outside the catheter body;

[0009] The bending wire is a shape memory alloy wire, and the first end of the bending wire is pre-shaped by heat treatment to form a bending portion; the bending degree of the first end of the catheter body can be adjusted by applying a force to the second end of the bending wire.

[0010] Optionally, the medical catheter further comprises an adjustment handle, the adjustment handle comprising a sleeve and a push rod, the push rod is located in the sleeve and can move axially along the sleeve; the sleeve is connected to the second end of the catheter body, and the push rod is connected to the second end of the bending adjustment wire.

[0011] Optionally, the adjustment handle also includes a limit piece, the outer wall portion of the push rod is recessed inward to form a groove, the groove is arranged along the axial direction of the push rod, and the outer wall of the sleeve is provided with a first through hole corresponding to the groove, one end of the limit piece is located in the groove, and the other end is at least partially located in the first through hole, and the size of the limit piece matches the groove to limit the push rod to move only along the axial direction of the sleeve.

[0012] Optionally, the limiting member can move along the axial direction of the first through hole, and when the limiting member moves to the first position, one end of the limiting member abuts against the bottom of the groove to fix the push rod.

[0013] Optionally, the limiting member includes a fixing member and an elastic member, one end of the fixing member is located in the groove, and the other end passes through the first through hole and is located outside the sleeve, the elastic member is sleeved on the fixing member, and the fixing member can move axially along the first through hole. When the fixing member moves to the first position, one end of the fixing member abuts against the bottom of the groove to fix the push rod and put the elastic member in a compressed state.

[0014] Optionally, a stroke mark is provided on the outer wall of the push rod, and the stroke mark is used to mark the distance that the push rod moves along the axial direction of the sleeve.

[0015] Optionally, the adjustment handle also includes a sealing ring, which is sleeved on the push rod, and one end of the sealing ring abuts against the end face of the first end of the sleeve, wherein the first end of the sleeve is the end of the sleeve farther from the second end of the catheter body, and when the push rod moves along the axial direction of the sleeve, the inner wall of the sealing ring is always in contact with the outer wall of the push rod.

[0016] Optionally, the bent portion is a U-shaped structure.

[0017] Optionally, the sleeve comprises a sleeve body and a connecting portion, and the connecting portion is connected to an end of the sleeve body closer to the second end of the catheter body;

[0018] The push rod is located in the sleeve body and can move along the axial direction of the sleeve body; the connecting portion is provided with a second through hole along the axial direction, and the second end of the catheter body is located in the second through hole and is bonded and fixed to the connecting portion.

[0019] In a second aspect, an embodiment of the present invention further provides a method for using a medical catheter, comprising:

[0020] During the process of the medical catheter entering the catheter, continuously observing the structure of the human blood vessel at the location of the first end of the medical catheter;

[0021] According to the human vascular structure at the real-time location of the first end of the medical catheter, the bending adjustment wire is controlled to adjust the bending degree of the bending portion of the first end of the bending adjustment wire until the first end of the medical catheter reaches the human vascular where the native valve is located;

[0022] Controlling the bending wire to adjust the bending degree of the bending portion until the first end of the medical catheter is coaxial with the human vessel where the native valve is located, and then releasing the artificial valve;

[0023] During the withdrawal of the medical catheter, continuously observing the structure of the human blood vessel at the location of the first end of the medical catheter;

[0024] According to the human vascular structure where the first end of the medical catheter is located in real time, the bending adjustment wire is controlled to adjust the bending degree of the bending portion until the medical catheter is withdrawn from the human vascular.

[0025] In this embodiment, the bending adjustment wire is a shape memory alloy wire, and the first end of the bending adjustment wire is pre-shaped by heat treatment to form a bending portion. Since the bending portion itself has a certain degree of bending, when the actual required bending degree of the bending portion is less than the bending degree formed by the pre-shaped bending portion, the bending degree of the bending portion can be adjusted to the required degree by simply pushing the bending adjustment wire. And since the bending portion has a tendency to restore to a natural state when not under force, the bending portion can be restored to its original state from a state with a smaller bending degree by simply stopping the force applied to the bending adjustment wire. Therefore, in this process, the bending adjustment wire is only subjected to a force along the axial direction of the bending adjustment wire and toward the first end of the bending adjustment wire. The bending degree formed by the pre-shaped bending portion after heat treatment can be adjusted according to the maximum bending degree actually required, so that the bending degree formed by the pre-shaped bending portion after heat treatment is greater than the maximum bending degree actually required, thereby reducing the probability of the connection between the bending adjustment wire and the catheter body being disconnected or the bending adjustment wire being broken due to excessive traction, thereby improving the safety of the medical catheter. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings required for use in the description of the embodiments of the present invention will be briefly introduced below. Obviously, the accompanying drawings in the following description are only some embodiments of the present invention. For ordinary technicians in this field, other accompanying drawings can be obtained based on these accompanying drawings without paying creative labor.

[0027] Figure 1 is a schematic structural diagram of a medical catheter provided by an embodiment of the present invention;

[0028] Figure 2is a schematic structural diagram of a curved portion of a medical catheter provided by an embodiment of the present invention;

[0029] Figure 3 is a schematic structural diagram of an adjustment handle of a medical catheter provided by an embodiment of the present invention;

[0030] Figure 4 is a schematic cross-sectional structure diagram of an adjustment handle of a medical catheter provided by an embodiment of the present invention;

[0031] Figure 5 is a schematic flow chart of a method for using a medical catheter provided by an embodiment of the present invention;

[0032] Figure 6 It is a schematic diagram of a situation in which the artificial valve is released by the medical catheter provided by an embodiment of the present invention and the human body blood vessel in which the native valve is located is not coaxial;

[0033] Figure 7 It is a schematic diagram of the situation when the medical catheter provided by an embodiment of the present invention releases an artificial valve and is coaxial with the human blood vessel where the native valve is located. DETAILED DESCRIPTION

[0034] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0035] Unless otherwise defined, the technical terms or scientific terms used in the present invention shall have the usual meanings understood by persons with ordinary skills in the field to which the present invention belongs. The words "first", "second" and similar words used in the present invention do not indicate any order, quantity or importance, but are only used to distinguish different components. "Up", "down", "left", "right" and the like are only used to indicate relative positional relationships. When the absolute position of the described object changes, the relative positional relationship also changes accordingly.

[0036] like Figure 1 and Figure 2 As shown, an embodiment of the present invention provides a medical catheter, comprising:

[0037] A catheter body 1, wherein a bending wire channel is provided in the catheter body 1, and the bending wire channel extends from a first end of the catheter body 1 and passes through a second end surface of the catheter body 1;

[0038] A bending adjustment wire 2, wherein a first end of the bending adjustment wire 2 is located inside the catheter body 1 and connected to the first end of the catheter body 1, and a second end of the bending adjustment wire 2 passes through the bending adjustment wire channel and is located outside the catheter body 1;

[0039] The bending wire 2 is a shape memory alloy wire, and the first end of the bending wire 2 is pre-shaped by heat treatment to form a bending portion; the bending degree of the first end of the catheter body 1 can be adjusted by applying a force to the second end of the bending wire 2.

[0040] It should be understood that since the bending wire 2 is a shape memory alloy wire, and the first end of the bending wire 2 is pre-shaped by heat treatment to form a curved portion, the shape of the curved portion can be changed arbitrarily under the action of external force, and when the external force disappears, the curved portion will automatically return to the predetermined shape according to the shape memory characteristics of the shape memory alloy wire.

[0041] It should be understood that the first end of the bending wire 2 is pre-shaped by heat treatment to form a bending portion, and the bending degree of the bending portion is not limited here.

[0042] Optionally, the bending wire 2 is a nickel-titanium alloy wire.

[0043] The medical catheter provided by the embodiment of the present invention can be used in transcatheter aortic valve replacement. In actual use, medical staff usually first insert the guide wire into the femoral artery and anchor it in the human blood vessel where the native valve is located, and then push the medical catheter into the path along the guide wire. During the process of the medical catheter entering the path, the medical staff can observe the structure of the human blood vessel where the first end of the medical catheter is located based on the medical image, and the operator can also judge the structure of the human blood vessel where the first end of the medical catheter is located based on the hand feel and resistance during the process of pushing the medical catheter into the path.

[0044] Since the first end of the bending adjustment wire 2 is located in the catheter body 1 and connected to the first end of the catheter body 1, when the shape of the curved portion changes, the shape of the first end of the catheter body 1 will also change accordingly. When the actual required bending degree of the curved portion is less than the bending degree formed by the predetermined shaping of the curved portion, the operator can apply a force along the axial direction of the bending adjustment wire 2 and toward the first end of the bending adjustment wire 2 to the second end of the bending adjustment wire 2, that is, the operator can adjust the bending degree of the curved portion to a desired state by pushing the bending adjustment wire 2. At the same time, since the bending adjustment wire 2 has a shape memory property, when the second end of the bending adjustment wire 2 is not subjected to an external force, the curved portion has a tendency to automatically return to the predetermined bending state. When the operator reduces the bending degree of the curved portion, when the operator releases the bending adjustment wire 2, the bending degree of the curved portion will automatically increase until the curved portion returns to a natural state. At this time, the operator only needs to re-apply a force to the bending adjustment wire 2 when the bending degree of the curved portion returns to the desired degree, so that the bending adjustment wire 2 can be fixed and the bending degree of the curved portion can be maintained at the desired degree. At this time, if the bending degree of the bending portion needs to be adjusted to a smaller value, the bending adjustment wire 2 can be pushed again. When the actual required bending degree of the bending portion is greater than the bending degree formed by the pre-forming of the bending portion, the operator needs to pull the bending adjustment wire 2 to make the bending degree of the bending portion greater than the pre-forming bending degree. Since the bending portion itself has a certain bending degree, the required pulling force at this time is less than the pulling force required to adjust the bending portion from a straight state to a desired bending state. In actual use, the bending degree of the pre-forming of the bending portion can be adjusted so that the pre-forming bending degree of the bending portion is greater than the maximum bending degree required in actual use.

[0045] The operator can adjust the direction and magnitude of the force applied to the bending wire 2 in real time according to the curvature of the human blood vessel where the first end of the medical catheter is located, so that the shape of the medical catheter is adapted to the shape of the human blood vessel to be passed through, thereby ensuring that the first end of the medical catheter can smoothly reach the human blood vessel where the native valve is located.

[0046] Usually, the artificial valve is loaded on the first end of the medical catheter. When the part of the medical catheter loaded with the artificial valve is not coaxial with the human blood vessel where the native valve is located, there is a risk that the artificial valve will be released inaccurately. Figure 6As shown, after the artificial valve is released, if the part of the medical catheter loaded with the artificial valve is not coaxial with the human blood vessel where the native valve is located, interference may occur between the medical catheter and the artificial valve, making it impossible for the medical catheter to be withdrawn smoothly or affecting the stability of the artificial valve during the withdrawal process. Therefore, when the first end of the medical catheter reaches the human blood vessel where the native valve is located, the operator observes the medical image, and when the part of the medical catheter loaded with the artificial valve is not coaxial with the human blood vessel where the native valve is located, the operator needs to control the bending wire 2 to adjust the bending degree of the bending portion until the part of the medical catheter loaded with the artificial valve is coaxial with the human blood vessel where the native valve is located, as shown in FIG. Figure 7 As shown, the artificial valve is released at this time, thereby avoiding the situation where the artificial valve is released at an inaccurate position.

[0047] After completing the release of the artificial valve, the operator needs to withdraw the medical catheter along the guide wire. In the process of withdrawing the medical catheter, the operator can also observe the structure of the human blood vessel where the first end of the medical catheter is located based on the medical image. At the same time, the operator can also judge the structure of the human blood vessel where the first end of the medical catheter is located based on the hand feel and resistance during the process of pushing the medical catheter into the route. The operator can adjust the direction and magnitude of the force applied to the bending wire 2 in real time according to the degree of curvature of the human blood vessel where the first end of the medical catheter is located, so that the shape of the medical catheter is adapted to the shape of the human blood vessel that needs to be passed, thereby ensuring that the medical catheter can be withdrawn smoothly.

[0048] In this embodiment, the bending adjustment wire 2 is a shape memory alloy wire, and the first end of the bending adjustment wire 2 is pre-shaped by heat treatment to form a bending portion. Since the bending portion itself has a certain degree of bending, when the actual required bending degree of the bending portion is less than the bending degree formed by the pre-shaped bending portion, the bending degree of the bending portion can be adjusted to the required degree by simply pushing the bending adjustment wire 2. And since the bending portion has a tendency to restore to a natural state when not under force, the bending portion can be restored to its original state from a state with a smaller bending degree by simply stopping the force applied to the bending adjustment wire 2. Therefore, in this process, the bending adjustment wire 2 is only subjected to a force along the axial direction of the bending adjustment wire 2 and toward the first end of the bending adjustment wire 2. The bending degree formed by the pre-shaped bending portion by heat treatment can be adjusted according to the maximum bending degree actually required, so that the bending degree formed by the pre-shaped bending portion by heat treatment is greater than the maximum bending degree actually required, thereby reducing the probability of the connection between the bending adjustment wire 2 and the catheter body 1 being disconnected or the bending adjustment wire 2 being broken due to excessive traction, thereby improving the safety of the medical catheter.

[0049] like Figure 3 and Figure 4 As shown, optionally, the medical catheter also includes an adjustment handle, which includes a sleeve 31 and a push rod 32, wherein the push rod 32 is located in the sleeve 31 and can move axially along the sleeve 31; the sleeve 31 is connected to the second end of the catheter body 1, and the push rod 32 is connected to the second end of the bending adjustment wire 2.

[0050] It should be understood that the connection method between the sleeve 31 and the second end of the catheter body 1 is not limited here. For example, in one embodiment, the sleeve 31 and the second end of the catheter body 1 are fixed by bonding. In another embodiment, the sleeve 31 and the second end of the catheter body 1 are connected by clamping.

[0051] It should be understood that the connection method between the push rod 32 and the second end of the bending adjustment wire 2 is not limited here. For example, in one embodiment, the push rod 32 and the second end of the bending adjustment wire 2 are fixed by welding. In another embodiment, the push rod 32 and the second end of the bending adjustment wire 2 are fixed by bonding.

[0052] During actual use of the medical catheter provided in this embodiment, since the push rod 32 is connected to the second end of the bending wire 2, when the push rod 32 moves along the axial direction of the sleeve 31, the bending wire 2 will also be subjected to a corresponding force. When the operator pushes the push rod 32, the bending wire 2 is subjected to a force along the axial direction of the bending wire 2 and toward the first end of the bending wire 2, so the degree of bending of the bending portion gradually decreases after being subjected to force, and the bending portion tends to form a straight line state. When the push rod 32 is not subjected to an external force, since the bending portion will automatically return to a predetermined bending state, the push rod 32 will also be subjected to a reaction force of the bending wire 2 and move to an initial position, and the initial position refers to the position of the push rod 32 when the bending portion is in a natural bending state.

[0053] In this embodiment, by setting the adjustment handle, the bending state of the bending portion can be controlled by controlling the distance that the push rod 32 moves along the axial direction of the sleeve 31. Due to the setting of the push rod 32, the operation convenience of the operator is improved.

[0054] Optionally, the adjustment handle also includes a limit member 33, and the outer wall portion of the push rod 32 is recessed inward to form a groove 321, and the groove 321 is arranged along the axial direction of the push rod 32. The outer wall of the sleeve 31 is provided with a first through hole corresponding to the groove 321. One end of the limit member 33 is located in the groove 321, and the other end is at least partially located in the first through hole. The size of the limit member 33 matches the groove 321 to limit the push rod 32 to move only along the axial direction of the sleeve 31.

[0055] It should be understood that the size of the limit member 33 matches the groove 321, which means that when the side wall of the limit member 33 abuts against the side wall of the groove 321, when one end of the limit member 33 is located in the groove 321, the push rod 32 can only move along the axial direction of the sleeve 31.

[0056] In this embodiment, due to the setting of the limiter 33, the push rod 32 can only move along the axial direction of the sleeve 31, that is, the push rod 32 can only apply a force along the axial direction of the push rod 32 to the bending wire 2, thereby preventing the push rod 32 from generating a torsional tension on the bending wire 2 when rotating along the axial direction, thereby further improving the safety of the medical catheter.

[0057] Optionally, the limiting member 33 can move along the axial direction of the first through hole. When the limiting member 33 moves to the first position, one end of the limiting member 33 abuts against the bottom of the groove 321 to fix the push rod 32.

[0058] It should be understood that the stopper 33 can move along the axial direction of the first through hole. When the stopper 33 moves to the first position, one end of the stopper 33 abuts against the bottom of the groove 321. The friction force generated by the one end of the stopper 33 and the bottom of the groove 321 prevents the push rod 32 from moving along the axial direction of the sleeve 31, thereby fixing the push rod 32. When the stopper 33 moves so that one end of the stopper 33 does not abut against the bottom of the groove 321, the push rod 32 can move along the axial direction of the sleeve 31 again.

[0059] It should be understood that the structure of the limit member 33 is not limited here. For example, in one embodiment, the limit member 33 is a set screw, and the inner wall of the first through hole is provided with a nut structure matching the set screw. The operator can move the set screw along the axial direction of the first through hole by rotating the set screw. In another embodiment, the limit member 33 is a cylindrical rod, one end of which is located in the groove 321, and the other end passes through the first through hole and is located outside the sleeve 31. When the operator applies a force to the cylindrical rod along the axial direction of the cylindrical rod and toward the groove 321, the cylindrical rod moves to the first position. When the operator applies a force to the cylindrical rod along the axial direction of the cylindrical rod and away from the groove 321, the cylindrical rod leaves the first position.

[0060] In this embodiment, when the stopper 33 moves to the first position, one end of the stopper 33 abuts against the bottom of the groove 321, so that the push rod 32 can be fixed, so that the force applied by the push rod 32 on the bending wire 2 is fixed, and the bending portion can be kept in a certain state. By moving the stopper 33, the push rod 32 can be fixed at different positions, so that the bending degree of the bending portion can be kept stable for a certain period of time.

[0061] Optionally, the limiting member 33 includes a fixing member 331 and an elastic member 332, one end of the fixing member 331 is located in the groove 321, and the other end passes through the first through hole and is located outside the sleeve 31, the elastic member 332 is sleeved on the fixing member 331, and the fixing member 331 can move axially along the first through hole. When the fixing member 331 moves to the first position, one end of the fixing member 331 abuts against the bottom of the groove 321 to fix the push rod 32 and at the same time put the elastic member 332 in a compressed state.

[0062] It should be understood that the structure of the elastic component 332 is not limited here. For example, in one embodiment, the elastic component 332 is a spring. In another embodiment, the elastic component 332 is a leaf spring.

[0063] In this embodiment, when the fixing member 331 moves to the first position, one end of the fixing member 331 abuts against the bottom of the groove 321 to fix the push rod 32 and put the elastic component 332 in a compressed state. At this time, a force needs to be applied to the fixing member 331 to keep the fixing member 331 in the first position. When the force applied to the fixing member 331 stops, the elastic component 332 applies a reaction force to the fixing member 331 to restore the natural state, so that one end of the fixing member 331 does not abut against the bottom of the groove 321. At this time, the push rod 32 can move along the axial direction of the sleeve 31.

[0064] In this embodiment, when the operator needs to fix the push rod 32, the operator needs to apply a force to the fixing member 331. When the operator does not need to fix the push rod 32, the operator only needs to stop applying a force to the fixing member 331, and the fixing member 331 can automatically move under the action of the elastic member 332. Through the above arrangement, the convenience of the operator's operation is improved.

[0065] Optionally, a stroke mark is provided on the outer wall of the push rod 32 , and the stroke mark is used to mark the distance that the push rod 32 moves along the axial direction of the sleeve 31 .

[0066] It should be understood that the stroke mark is set on the outer wall of the push rod 32, and when the push rod 32 moves along the axial direction of the sleeve 31, the length of the portion of the push rod 32 outside the sleeve 31 is different. According to the stroke mark on the portion outside the sleeve 31, the distance that the push rod 32 moves along the axial direction of the sleeve 31 can be determined.

[0067] It should be understood that the specific structure of the stroke identifier is not limited herein. For example, in one embodiment, the outer wall of the push rod 32 is provided with digital identifiers at equal intervals, and when the push rod 32 moves along the axial direction of the sleeve 31, the numbers of the portion located outside the sleeve 31 can identify the distance that the push rod 32 moves along the axial direction of the sleeve 31. In another embodiment, the outer wall of the push rod 32 is provided with an annular groove 321 along the circumferential direction, and the number of the annular grooves 321 is multiple, and the multiple annular grooves 321 are arranged at equal intervals along the axial direction of the push rod 32. When the push rod 32 moves along the axial direction of the sleeve 31, the number of the annular grooves 321 located outside the sleeve 31 can identify the distance that the push rod 32 moves along the axial direction of the sleeve 31.

[0068] In this embodiment, the corresponding relationship between the distance that the push rod 32 moves along the axial direction of the sleeve 31 and the bending degree of the bending portion can usually be obtained through experiments, so that the stroke mark can be used as a basis for judging the bending degree of the bending portion. The stroke mark can be used as a reference for judging the bending degree of the bending portion, thereby helping operators to better judge the bending degree of the bending portion in real time.

[0069] Optionally, the adjustment handle also includes a sealing ring 34, which is sleeved on the push rod 32, and one end of the sealing ring 34 abuts against the end face of the first end of the sleeve 31, wherein the first end of the sleeve 31 is an end of the sleeve 31 farther from the second end of the catheter body 1, and when the push rod 32 moves along the axial direction of the sleeve 31, the inner wall of the sealing ring 34 is always in contact with the outer wall of the push rod 32.

[0070] In this embodiment, the adjustment handle also includes a sealing ring 34. The setting of the sealing ring 34 can prevent blood or gas from entering or exiting the gap between the push rod 32 and the sleeve 31 when the push rod 32 moves axially along the sleeve 31, thereby ensuring the sealing of the medical catheter.

[0071] Optionally, the bent portion is a U-shaped structure.

[0072] In this embodiment, the bending portion is pre-shaped into a U-shaped structure by heat treatment. In practical applications, the actual required bending degree of the bending portion is less than the bending degree of the U-shaped structure formed by the pre-shaped bending portion. Therefore, when adjusting the bending degree of the bending adjustment wire 2, in most cases, it is only necessary to apply a force along the axial direction of the bending adjustment wire 2 and toward the first end of the bending adjustment wire 2 to the second end of the bending adjustment wire 2, that is, the operator can adjust the bending degree of the bending portion to the desired state by pushing the bending adjustment wire 2. Secondly, when the bending degree of the bending portion is reduced to a certain bending degree, if it is necessary to increase the bending degree of the bending portion on this basis, it is only necessary to reduce the force applied to the second end of the bending adjustment wire 2. At this time, the bending portion will tend to return to the predetermined structure, and no additional traction force is required in this process.

[0073] Therefore, the medical catheter provided in this embodiment basically does not need to apply traction force to the bending adjustment wire 2 during use. The medical catheter can be smoothly passed through various human vessels by only adjusting the thrust applied to the bending adjustment wire 2, thereby further improving the safety of the medical catheter.

[0074] Optionally, the sleeve 31 includes a sleeve 31 body and a connecting portion, and the connecting portion is connected to an end of the sleeve 31 body that is closer to the second end of the catheter body 1;

[0075] The push rod 32 is located in the sleeve 31 body and can move along the axial direction of the sleeve 31 body; the connecting portion is axially provided with a second through hole, and the second end of the catheter body 1 is located in the second through hole and is bonded and fixed to the connecting portion.

[0076] It should be understood that the connection method between the connecting portion and the end of the sleeve 31 body closer to the second end of the catheter body 1 is not limited here. For example, in one embodiment, the connecting portion and the sleeve 31 body are integrally formed. In another embodiment, the connecting portion and the end of the sleeve 31 body closer to the second end of the catheter body 1 are welded and fixed. In another embodiment, the connecting portion and the end of the sleeve 31 body closer to the second end of the catheter body 1 are clamped and fixed.

[0077] It should be understood that the diameter of the second through hole matches the diameter of the catheter body 1 , and the second end of the catheter body 1 is located in the second through hole and fits against the inner wall of the second through hole.

[0078] In this embodiment, since the second end of the catheter body 1 is located in the second through hole, the contact area between the second end of the catheter body 1 and the connecting portion is increased, thereby improving the connection stability between the catheter body 1 and the connecting portion.

[0079] like Figure 5 As shown, an embodiment of the present invention also provides a method for using a medical catheter, comprising:

[0080] Step 101, during the process of inserting the medical catheter, continuously observing the structure of the human blood vessel where the first end of the medical catheter is located;

[0081] The medical catheter provided by the embodiment of the present invention can be used in transcatheter aortic valve replacement. In actual use, medical staff usually first insert the guide wire into the femoral artery and anchor it in the human blood vessel where the native valve is located, and then push the medical catheter into the path along the guide wire. During the process of the medical catheter entering the path, the medical staff can observe the structure of the human blood vessel where the first end of the medical catheter is located based on the medical image, and the operator can also judge the structure of the human blood vessel where the first end of the medical catheter is located based on the hand feel and resistance during the process of pushing the medical catheter into the path.

[0082] Step 102, according to the human vascular structure where the first end of the medical catheter is located in real time, controlling the bending wire 2 to adjust the bending degree of the bending portion of the first end of the bending wire 2 until the first end of the medical catheter reaches the human vascular where the native valve is located;

[0083] Since the first end of the bending adjustment wire 2 is located in the catheter body 1 and connected to the first end of the catheter body 1, when the shape of the curved portion changes, the shape of the first end of the catheter body 1 will also change accordingly. When the actual required bending degree of the curved portion is less than the bending degree formed by the predetermined shaping of the curved portion, the operator can apply a force along the axial direction of the bending adjustment wire 2 and toward the first end of the bending adjustment wire 2 to the second end of the bending adjustment wire 2, that is, the operator can adjust the bending degree of the curved portion to a desired state by pushing the bending adjustment wire 2. At the same time, since the bending adjustment wire 2 has a shape memory property, when the second end of the bending adjustment wire 2 is not subjected to an external force, the curved portion has a tendency to automatically return to the predetermined bending state. When the operator reduces the bending degree of the curved portion, when the operator releases the bending adjustment wire 2, the bending degree of the curved portion will automatically increase until the curved portion returns to a natural state. At this time, the operator only needs to re-apply a force to the bending adjustment wire 2 when the bending degree of the curved portion returns to the desired degree, so that the bending adjustment wire 2 can be fixed and the bending degree of the curved portion can be maintained at the desired degree. If the bending degree of the bending portion needs to be adjusted to a smaller value, the bending adjustment wire 2 can be pushed again. When the actual bending degree of the bending portion is greater than the bending degree formed by the predetermined shaping of the bending portion, the operator needs to pull the bending adjustment wire 2 to make the bending degree of the bending portion greater than the predetermined shaping degree. Since the bending portion itself has a certain bending degree, the required pulling force at this time is less than the pulling force required to adjust the bending portion from a straight state to a desired bending state.

[0084] The operator can adjust the direction and magnitude of the force applied to the bending wire 2 in real time according to the curvature of the human blood vessel where the first end of the medical catheter is located, so that the shape of the medical catheter is adapted to the shape of the human blood vessel to be passed through, thereby ensuring that the first end of the medical catheter can smoothly reach the human blood vessel where the native valve is located.

[0085] Step 103, controlling the bending wire 2 to adjust the bending degree of the bending portion until the first end of the medical catheter is coaxial with the human vessel where the native valve is located, and then releasing the artificial valve;

[0086] Usually, the artificial valve is loaded on the first end of the medical catheter. When the part of the medical catheter loaded with the artificial valve is not coaxial with the human blood vessel where the native valve is located, there is a risk that the artificial valve will be released inaccurately. Figure 6As shown, after the artificial valve is released, if the part of the medical catheter loaded with the artificial valve is not coaxial with the human blood vessel where the native valve is located, interference may occur between the medical catheter and the artificial valve, making it impossible for the medical catheter to be withdrawn smoothly or affecting the stability of the artificial valve during the withdrawal process. Therefore, when the first end of the medical catheter reaches the human blood vessel where the native valve is located, the operator observes the medical image, and when the part of the medical catheter loaded with the artificial valve is not coaxial with the human blood vessel where the native valve is located, the operator needs to control the bending wire 2 to adjust the bending degree of the bending portion until the part of the medical catheter loaded with the artificial valve is coaxial with the human blood vessel where the native valve is located, as shown in FIG. Figure 7 As shown, the artificial valve is released at this time, thereby avoiding the situation where the artificial valve is released at an inaccurate position.

[0087] Step 104, during the process of withdrawing the medical catheter, continuously observing the structure of the human blood vessel at the location of the first end of the medical catheter;

[0088] Step 105 , according to the human vascular structure where the first end of the medical catheter is located in real time, the bending adjustment wire 2 is controlled to adjust the bending degree of the bending portion until the medical catheter is withdrawn from the human vascular structure.

[0089] After completing the release of the artificial valve, the operator needs to withdraw the medical catheter along the guide wire. In the process of withdrawing the medical catheter, the operator can also observe the structure of the human blood vessel where the first end of the medical catheter is located based on the medical image. At the same time, the operator can also judge the structure of the human blood vessel where the first end of the medical catheter is located based on the hand feel and resistance during the process of pushing the medical catheter into the route. The operator can adjust the direction and magnitude of the force applied to the bending wire 2 in real time according to the degree of curvature of the human blood vessel where the first end of the medical catheter is located, so that the shape of the medical catheter is adapted to the shape of the human blood vessel that needs to be passed, thereby ensuring that the medical catheter can be withdrawn smoothly.

[0090] The above are only specific embodiments of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art who is familiar with the technical field can easily think of changes or substitutions within the technical scope disclosed by the present invention, which should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention should be based on the protection scope of the claims.

Claims

1. A medical catheter, characterized in that: include: A catheter body, wherein a bending wire channel is provided in the catheter body, and the bending wire channel extends from the first end of the catheter body and passes through the second end surface of the catheter body; A bending adjustment wire, wherein a first end of the bending adjustment wire is located in the catheter body and connected to the first end of the catheter body, and a second end of the bending adjustment wire passes through the bending adjustment wire channel and is located outside the catheter body; The bending adjustment wire is a shape memory alloy wire, and the first end of the bending adjustment wire is pre-shaped by heat treatment to form a bending portion; the bending degree of the first end of the catheter body can be adjusted by applying a force to the second end of the bending adjustment wire; An adjusting handle, the adjusting handle includes a sleeve and a push rod; the sleeve is connected to the second end of the catheter body, and the push rod is connected to the second end of the bending adjustment wire; the adjusting handle also includes a limit piece, the outer wall portion of the push rod is recessed inward to form a groove, the groove is arranged along the axial direction of the push rod, and the outer wall of the sleeve is provided with a first through hole corresponding to the groove, one end of the limit piece is located in the groove, and the other end is at least partially located in the first through hole, the size of the limit piece matches the groove to limit the push rod to move only along the axial direction of the sleeve; the outer wall of the push rod is provided with a stroke mark, and the stroke mark is used to mark the distance that the push rod moves along the axial direction of the sleeve.

2. The medical catheter according to claim 1, characterized in that: The limiting member can move along the axial direction of the first through hole. When the limiting member moves to the first position, one end of the limiting member abuts against the bottom of the groove to fix the push rod.

3. The medical catheter according to claim 2, characterized in that: The limiting member includes a fixing member and an elastic member, one end of the fixing member is located in the groove, and the other end passes through the first through hole and is located outside the sleeve, the elastic member is sleeved on the fixing member, and the fixing member can move along the axial direction of the first through hole. When the fixing member moves to the first position, one end of the fixing member abuts against the bottom of the groove to fix the push rod and put the elastic member in a compressed state.

4. The medical catheter according to claim 1, characterized in that: The adjustment handle also includes a sealing ring, which is sleeved on the push rod, and one end of the sealing ring abuts against the end face of the first end of the sleeve, wherein the first end of the sleeve is the end of the sleeve farther from the second end of the catheter body, and when the push rod moves along the axial direction of the sleeve, the inner wall of the sealing ring is always in contact with the outer wall of the push rod.

5. The medical catheter according to claim 1, characterized in that: The bent portion is a U-shaped structure.

6. The medical catheter according to claim 1, characterized in that The sleeve comprises a sleeve body and a connecting portion, wherein the connecting portion is connected to an end of the sleeve body closer to the second end of the catheter body; The push rod is located in the sleeve body and can move along the axial direction of the sleeve body; the connecting portion is provided with a second through hole along the axial direction, and the second end of the catheter body is located in the second through hole and is bonded and fixed to the connecting portion.

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