Extended catheter

Abstract

The invention discloses an extended catheter, which belongs to the technical field of interventional therapy instruments and comprises a push rod and a catheter connected to the far end of the push rod. The catheter comprises a catheter near-end section and a catheter far-end section, the catheter far-end section is located at the farthest end of the catheter, the diameter of the catheter far-end section is smaller than that of the catheter near-end section, and the outer wall of the catheter far-end section is provided with a flow guide groove which is concave inwards. The catheter far-end section with the reduced outer diameter is arranged at the farthest end of the catheter, so that the catheter can conveniently pass through a small and narrow blood vessel; the outer tube wall of the far-end section of the catheter is provided with the flow guide groove which is concave inwards, and in the operation process, when the outer tube wall of the far-end section of the catheter is attached to the wall of a blood vessel, blood in the blood vessel can flow towards the far end along the flow guide groove, so that the phenomenon that local blood pressure is too high due to blockage of the blood vessel is avoided, and damage to a human body caused by long-time blocking of the blood vessel by the catheter is avoided; therefore, the catheter can be safely inserted into a narrow blood vessel deeper in the body.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of interventional medical instruments, and particularly relates to an extension catheter. BACKGROUND

[0002] Percutaneous transluminal coronary intervention (PCI) refers to a technology of using percutaneous puncture technology to send in a balloon catheter or other related instruments to remove coronary artery stenosis or obstruction and to reconstruct coronary artery blood flow. Minimally invasive interventional treatment for treating diseases such as heart and blood vessels by inserting a catheter into a blood vessel is widely practiced.

[0003] In interventional treatment, a guide catheter is used to guide a treatment device (such as a balloon catheter, a stent delivery catheter, etc.) to a lesion. However, a single guide catheter cannot provide sufficient back support, and the further away from the heart, the narrower and more curved the blood vessels are, and the guide catheter cannot continue to be deepened due to a large diameter. Therefore, in addition to the guide catheter, an extension catheter is also used to deliver the treatment device.

[0004] When the extension catheter enters a narrow branch blood vessel, the tube wall of the catheter is in close contact with the blood vessel wall, which can cause blood vessel occlusion, and the blood flow in the blood vessel cannot fully flow forward, and the blood supply of part of the tissue is interrupted. Once the blood flow is interrupted for too long, it can cause serious damage to the human body. In order to ensure the safety of the operation, the existing extension catheter generally does not enter the narrow branch blood vessel.

[0005] Therefore, how to develop an extension catheter that can enter a narrow branch blood vessel and does not block the branch blood vessel. SUMMARY

[0006] Therefore, the present application provides an extension catheter to solve the problem that the existing extension catheter easily blocks the branch blood vessel when entering the narrow branch blood vessel and causes damage to the human body.

[0007] To solve the above technical problems, the technical scheme of the present application is as follows: An extension catheter, comprising a push rod and a catheter connected to the distal end of the push rod; the catheter comprises a catheter proximal end segment and a catheter distal end segment, the catheter distal end segment is located at the farthest end of the catheter, the diameter of the catheter distal end segment is smaller than the diameter of the catheter proximal end segment, and the outer tube wall of the catheter distal end segment is provided with a flow guide groove which is inwardly recessed and used for guiding blood flow.

[0008] By adopting the above scheme, when the outer tube wall of the catheter distal section is attached to the blood vessel wall during the operation process, the blood flow in the blood vessel can flow to the distal end along the flow guide groove, avoiding the phenomenon of local high blood pressure due to blockage of the blood vessel, and avoiding damage to the human body caused by long-term blockage of the blood vessel by the catheter.

[0009] Further, the distal end of the flow guide groove extends to the distal end face of the catheter distal section.

[0010] By adopting the above scheme, the blood flow in the flow guide groove can flow outwards through the distal end of the catheter, facilitating smooth flow of the blood flow in the flow guide groove, and avoiding the phenomenon of local high blood pressure due to blockage of the blood vessel.

[0011] Further, the flow guide groove is provided with a plurality of flow guide holes, the flow guide holes being configured to allow the blood flow outside the catheter distal section to enter the inner cavity of the catheter distal section, and the blood flow in the inner cavity of the catheter distal section being configured to flow out of the catheter distal section through the flow guide holes.

[0012] By adopting the above scheme, by providing the flow guide groove with a plurality of flow guide holes for blood flow to enter and exit, the blood flow in the blood vessel can flow from the outside of the catheter to the inside of the catheter through the flow guide holes, and also flow back from the inside of the catheter to the outside of the catheter, providing sufficient forward blood flow, avoiding the phenomenon of local high blood pressure due to blockage of the blood vessel; during the operation process, when the outer tube wall of the catheter distal section is attached to the blood vessel wall, the blood vessel wall will not block the flow guide holes on the catheter.

[0013] Further, the flow guide groove is a spiral groove that spirally surrounds the outer periphery of the catheter distal section.

[0014] Further, the plurality of flow guide holes are arranged in a straight line along the axial direction of the catheter distal section.

[0015] Further, the catheter is provided with a developing member, the developing member including a developing strip, and the developing strip and the plurality of flow guide holes are arranged in a straight line.

[0016] By adopting the above scheme, the developing member on the catheter can display the position of the catheter in the blood vessel, and at the same time, the developing strip of the developing member and the plurality of flow guide holes are arranged in a straight line, which can achieve the purpose of directing the flow guide holes, and during the operation, by adjusting the direction of the plurality of flow guide holes, the plurality of flow guide holes can be located on the side away from the blood vessel wall, so as to better ensure smooth flow of the blood flow.

[0017] Further, the developing member further includes a pair of developing rings, the pair of developing rings being located at the proximal end of the catheter distal section or at the distal end of the catheter proximal section, and the developing strip being located between the pair of developing rings.

[0018] Further, the flow guide groove is a straight line type groove extending along the axial direction of the catheter distal end section.

[0019] Further, the straight line type groove is provided with a plurality of straight line type grooves along the circumferential direction of the catheter distal end section, and each of the straight line type grooves is provided with a plurality of flow guide holes, and the flow guide holes on the same straight line type groove are arranged in a straight line.

[0020] Further, the catheter is provided with a developing member, which comprises a pair of developing rings located at the proximal end of the catheter distal end section or the distal end of the catheter proximal end section, and a plurality of developing strips located between the pair of developing rings, and each of the developing strips and one of the straight line type grooves are arranged in a straight line.

[0021] The technical scheme of the present application has the following advantages: by arranging the catheter distal end section with a reduced outer diameter at the distal end of the catheter, the catheter is facilitated to pass through small and narrow blood vessels; by arranging the inwardly recessed flow guide groove on the outer tube wall of the catheter distal end section, when the outer tube wall of the catheter distal end section is attached to the blood vessel wall during the operation, the blood flow in the blood vessel can flow along the flow guide groove to the distal end, avoiding the phenomenon of local high blood pressure due to blockage of the blood vessel, and avoiding damage to the human body caused by long-term blockage of the blood vessel by the catheter. BRIEF DESCRIPTION OF DRAWINGS

[0022] In order to more clearly illustrate the specific embodiments of the present application or the technical scheme in the prior art, the following will briefly introduce the drawings needed to be used in the description of the specific embodiments or the prior art. Obviously, the drawings described below are some embodiments of the present application, and those skilled in the art can also obtain other drawings according to these drawings without creative labor.

[0023] Figure 1 Fig. 1 is a schematic view of the overall structure of the extension catheter in the first embodiment of the present application; Figure 2 Fig. 2 is a schematic view of the structure of the catheter distal end section in the first embodiment of the present application; Figure 3 Fig. 3 is a schematic view of the structure of the catheter provided with a developing member in the first embodiment of the present application; Figure 4 Fig. 4 is a schematic view of the overall structure of the extension catheter in the second embodiment of the present application.

[0024] Fig. 1 is a schematic view of the overall structure of the extension catheter in the first embodiment of the present application; DETAILED DESCRIPTION

[0025] The technical solution of the present invention will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0026] In the description of this application, it should be understood that the terms "proximal" and "distal" throughout refer to near and far relative to the operator. In use, the end closer to the doctor or operator is the "proximal" end, i.e., the end where the handle is located, and the end farther from the doctor or operator is the "distal" end, i.e., the end farther from the handle. The above descriptions of orientation are merely for the convenience of describing this application and for simplification, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation; therefore, they should not be construed as limitations on this application.

[0027] Example 1 like Figures 1-3 The illustrated extension catheter includes a handle 1, a push rod 2, and a catheter 3. The proximal end of the push rod 2 is fixedly connected to the handle 1, and the catheter 3 is connected to the distal end of the push rod 2. The catheter 3 is flexible and can conform to the bending and deformation of the blood vessel. During the procedure, the catheter 3 is pushed into the blood vessel by the back-and-forth movement of the handle 1 and the push rod 2, so as to push the catheter 3 to the designated location of the tortuous and narrow branch blood vessel in the body for treatment.

[0028] In some embodiments of this example, the distal end of the push rod 2 is integrally formed with the conduit 3. Compared with the prior art, where the push rod 2 and the conduit 3 are separately set and then welded together, the connection between the push rod 2 and the conduit 3 is more robust, and the risk of breakage during the push process is less likely to occur.

[0029] In this embodiment, the catheter 3 includes a proximal segment 31 and a distal segment 32. The distal segment 32 is located at the distal end of the catheter 3, and its diameter is smaller than that of the proximal segment 31. The outer wall of the distal segment 32 is provided with an inwardly recessed flow-guiding groove 321 for guiding blood flow. The distal end of the flow-guiding groove 321 extends to the distal end face of the distal segment 32.

[0030] The outer diameter of the distal end section 32 of the catheter 3 is designed to be smaller, so that the catheter 3 can pass through the narrow and small blood vessels. The inner wall of the distal end section 32 is provided with a concave flow guide groove 321. During the operation, when the outer wall of the distal end section 32 is attached to the wall of the blood vessel, the blood flow in the blood vessel can flow to the distal end along the flow guide groove 321 and flow outwards through the distal end of the catheter 3. The blood flow can smoothly flow in the flow guide groove 321, avoiding the phenomenon of local high blood pressure caused by the blockage of the blood vessel, and avoiding the damage to the human body caused by the long-term blockage of the blood vessel by the catheter 3.

[0031] In this embodiment, the flow guide groove 321 is provided with a plurality of flow guide holes 322. The flow guide holes 322 can allow the blood flow outside the distal end section 32 to enter the inner cavity of the distal end section 32, and the blood flow in the inner cavity of the distal end section 32 can flow out of the distal end section 32 through the flow guide holes 322. When the catheter 3 is inserted into the blood vessel, the blood flow in the blood vessel can flow from the outside of the catheter 3 to the inside of the catheter 3 through the flow guide holes 322, and can also flow back from the inside of the catheter 3 to the outside of the catheter 3. The cavity in the catheter 3 can provide sufficient forward blood flow, avoiding the phenomenon of local high blood pressure caused by the blockage of the blood vessel. During the operation, when the outer wall of the distal end section 32 is attached to the wall of the blood vessel, the wall of the blood vessel will not block the flow guide holes 322 on the catheter 3.

[0032] In the embodiment, the flow guide groove 321 is a spiral groove spirally arranged around the outer periphery of the catheter distal section 32, and the plurality of flow guide holes 322 are arranged on the groove bottom of the flow guide groove 321 and are arranged in straight line along the axial direction of the catheter distal section 32. Since the diameter of the blood vessel closer to the distal end is generally smaller, when the catheter 3 is inserted into the blood vessel, the distal outer wall of the catheter distal section 32 can be in contact with the blood vessel wall, and the distal part of the flow guide groove 321 is blocked by the blood vessel wall, but the proximal outer wall of the catheter distal section 32 can not be in contact with the blood vessel wall, and the proximal part of the flow guide groove 321 and the partial flow guide holes 322 thereon are not blocked by the blood vessel wall, so that the blood flow at the proximal end of the blood vessel can flow to the distal part of the flow guide groove 321 which is not blocked by the blood vessel wall through the proximal part of the flow guide groove 321 which is not blocked by the blood vessel wall, and then flow to the distal end of the blood vessel through the distal opening of the flow guide groove 321; at the same time, the blood flow at the proximal end of the blood vessel can also enter the catheter 3 lumen through the partial flow guide holes 322 at the proximal end of the flow guide groove 321, and then flow out of the catheter 3 through the partial flow guide holes 322 at the distal end of the flow guide groove 321 after flowing in the catheter 3 lumen for a distance, and finally flow to the distal end of the blood vessel through the distal opening of the flow guide groove 321, so as to ensure the normal flow of the blood flow; if the distal end of the catheter 3 is an opening, the blood flow entering the catheter 3 can also directly flow to the distal end of the blood vessel through the distal opening of the catheter 3, so that the blood flow can smoothly realize forward flow in the case that the catheter 3 is inserted into the blood vessel, thereby avoiding the phenomenon that the local blood pressure is too high due to the blockage of the blood vessel, so that the catheter 3 can be safely inserted into the narrow blood vessel deeper in the body.

[0033] In the embodiment, the catheter 3 is provided with a developing member 4, and the developing member 4 further comprises a pair of developing rings 42 and a developing strip 41 located between the pair of developing rings 42, and the pair of developing rings 42 are located on the outer periphery of the position where the catheter proximal section 31 meets the catheter distal section 32. The developing member 4 is used to show the position of the catheter 3 in the blood vessel, so as to determine whether the catheter 3 is inserted into the treatment position of the blood vessel. The developing strip 41 of the developing member 4 and the plurality of flow guide holes 322 are arranged in straight line, which can realize the purpose of directing the flow guide holes 322, and during the operation, the direction of the plurality of flow guide holes 322 can be adjusted so that the plurality of flow guide holes 322 are located on the side as far as possible from the blood vessel wall, so as to better ensure the smooth flow of the blood flow. It can be understood here that the pair of developing rings 42 can also be located on the outer periphery of the position where the catheter distal section 32 meets the catheter proximal section 31, as long as the developing member 4 is located on the outer wall of the catheter 3 proximal to the flow guide groove 321 and can develop.

[0034] Embodiment two As Figure 4The difference between the shown elongated catheter and the catheter of the first embodiment is that the flow guide groove 321 is a straight line groove extending along the axial direction of the catheter distal section 32, and a plurality of straight line grooves are arranged along the circumferential direction of the catheter distal section 32. Each straight line groove is provided with a plurality of flow guide holes 322, and the flow guide holes 322 in the same straight line groove are arranged in a straight line. When the catheter 3 is inserted into the blood vessel, the distal end part of the straight line groove is blocked by the blood vessel wall, but the proximal end part of the straight line groove and the flow guide holes 322 thereon are not blocked by the blood vessel wall. Therefore, the blood flow at the proximal end of the blood vessel can flow in a straight line to the distal end part of the straight line groove through the proximal end part of the straight line groove which is not blocked by the blood vessel wall, and then flow to the distal end of the blood vessel through the distal end opening of the straight line groove. At the same time, the blood flow at the proximal end of the blood vessel can also enter the catheter 3 lumen through the flow guide holes 322 at the proximal end of the straight line groove. After flowing in the catheter 3 lumen for a distance, the blood flow flows out of the catheter 3 through the flow guide holes 322 at the distal end of the straight line groove, and finally flows to the distal end of the blood vessel through the distal end opening of the flow guide groove 321. If the distal end of the catheter 3 is open, the blood flow entering the catheter 3 can also flow directly to the distal end of the blood vessel through the distal end opening of the catheter 3, which facilitates the smooth forward flow of the blood flow in the blood vessel inserted into the catheter 3.

[0035] Compared with the scheme of the first embodiment, the plurality of straight line grooves can provide more flow paths for blood, and the forward flow of blood is more smooth. Moreover, since the blood vessel has elasticity, the blood vessel wall may be squeezed into the flow guide groove 321 on the outer wall of the catheter 3. When the plurality of straight line grooves are arranged along the circumferential direction of the catheter 3, even if the blood vessel wall is squeezed into the straight line groove on one side of the catheter 3, the blood vessel wall is difficult to be squeezed into the plurality of straight line grooves on the outer circumference of the catheter 3 at the same time. At least part of the straight line grooves and the flow guide holes 322 thereon are not blocked by the blood vessel wall, thereby better ensuring the forward flow of the blood flow.

[0036] In some embodiments of the second embodiment, the catheter 3 can also be provided with a similar developing member 4 as in the first embodiment, and the difference is that a pair of developing rings 42 can be provided with a plurality of spaced developing strips 41, and each developing strip 41 and one straight line groove are arranged in a straight line. In this way, the position of the catheter 3 and the direction of the flow guide holes 322 on the plurality of straight line grooves are developed, so that as many straight line grooves and flow guide holes 322 thereon as possible are located on the side away from the blood vessel wall, so as to better ensure the smooth flow of the blood flow.

[0037] In summary, the elongated catheter provided by the embodiments of the present application has the following beneficial effects: 1. By providing the catheter distal section 32 with a reduced outer diameter at the farthest end of the catheter 3, the catheter 3 can pass through a small and narrow blood vessel. 2. The inner recessed flow guide groove 321 is arranged on the outer tube wall of the catheter distal section 32. During the operation, when the outer tube wall of the catheter distal section 32 is attached to the blood vessel wall, the blood flow in the blood vessel can flow distally along the flow guide groove 321, avoiding the phenomenon of local high blood pressure due to blockage of the blood vessel, and avoiding the damage to the human body caused by long-term blockage of the blood vessel by the catheter 3; 3. The flow guide hole 322 is arranged on the flow guide groove 321, allowing the blood flow in the blood vessel to flow from the outside of the catheter 3 to the inside of the catheter 3 through the flow guide hole 322, providing sufficient forward blood flow, further avoiding the phenomenon of local high blood pressure due to blockage of the blood vessel; during the operation, when the outer tube wall of the catheter distal section 32 is attached to the blood vessel wall, the blood vessel wall will not block the flow guide hole 322 on the catheter 3; 4. The developing member 4 on the catheter 3 can show the position of the catheter 3 in the blood vessel, and the developing strip 41 of the developing member 4 and the plurality of flow guide holes 322 are in a straight line, which can achieve the purpose of directing the flow guide hole 322; during the operation, the orientation of the plurality of flow guide holes 322 can be adjusted, so that the plurality of flow guide holes 322 are located on the side away from the blood vessel wall, to better ensure the smooth flow of the blood flow.

[0038] Obviously, the above embodiments are only examples for clear illustration, and are not limitations on the embodiments. Based on the above description, other different forms of changes or variations can be made by those of ordinary skill in the art. Here, it is not necessary and impossible to exhaust all the embodiments. The obvious changes or variations derived therefrom are still within the protection scope of the present application.

Claims

1. An extension catheter, characterized in that, It includes a push rod (2) and a conduit (3) connected to the distal end of the push rod (2); the conduit (3) includes a proximal section (31) and a distal section (32), the distal section (32) is located at the farthest end of the conduit (3), the diameter of the distal section (32) is smaller than the diameter of the proximal section (31), and the outer wall of the distal section (32) is provided with an inwardly recessed flow guide groove (321).

2. The extension catheter according to claim 1, characterized in that, The distal end of the flow-guiding groove (321) extends to the distal end face of the distal segment (32) of the conduit.

3. The extension catheter according to claim 1, characterized in that, The flow-guiding groove (321) is provided with a plurality of flow-guiding holes (322), which allow blood flow from outside the distal segment (32) of the catheter to enter the inner cavity of the distal segment (32).

4. The extension catheter according to claim 3, characterized in that, The flow guide groove (321) is a spiral groove that surrounds the outer periphery of the distal section (32) of the conduit in a spiral shape.

5. The extension catheter according to claim 4, characterized in that, The plurality of the flow guide holes (322) are arranged in a straight line along the axial direction of the distal section (32) of the conduit.

6. The extension catheter according to claim 5, characterized in that, The conduit (3) is provided with a developing element (4), which includes a developing strip (41) and the developing strip (41) and the plurality of the guiding holes (322) are arranged in a straight line.

7. The extension catheter according to claim 6, characterized in that, The imaging element (4) further includes a pair of imaging rings (42), which are located at the proximal end of the distal segment (32) of the catheter or at the distal end of the proximal segment (31) of the catheter, and the imaging strip (41) is located between the pair of imaging rings (42).

8. The extension catheter according to any one of claims 1-3, characterized in that, The flow guide groove (321) is a straight groove extending axially along the distal end section (32) of the conduit.

9. The extension catheter according to claim 8, characterized in that, Multiple straight grooves are provided along the circumference of the distal section (32) of the conduit, and each straight groove is provided with a guide hole (322). Multiple guide holes (322) on the same straight groove are arranged in a straight line.

10. The extension catheter according to claim 9, characterized in that, The catheter (3) is provided with a radiopaque element (4), which includes a pair of radiopaque rings (42) located at the proximal end of the distal segment (32) of the catheter or at the distal end of the proximal segment (31) of the catheter, and a plurality of radiopaque strips (41) located between the pair of radiopaque rings (42), each radiopaque strip (41) and one of the linear grooves being arranged in a straight line.

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