Suction catheter

Abstract

The suction catheter comprises a catheter body, a handle connected to the near end of the catheter body and a head end part connected to the far end of the catheter body, and the head end part comprises a protective cover and a rotary grinding head arranged in the protective cover. A cable is arranged in the catheter, the cable extends to the far end of the head end part and is fixedly connected with the rotary grinding head, and the protective cover is provided with a hollow structure. And the cable is configured to drive the rotary grinding head to rotate so as to smash thrombus entering the protective cover. According to the technical scheme, the catheter can intervene in a blood vessel of a human body, and the handle is used for being held by an operator. Thrombus can pass through the hollow structure of the protective cover, and then the cable drives the rotating rotary grinding head to crush the thrombus. The thrombus crushed by the rotary grinding head is small in size, so that the clogging condition is not easy to occur when the crushed thrombus is sucked out; and the rotary grinding head is arranged in the protective cover, so that the blood vessel is not easy to damage.

Description

Technical Field

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

[0002] Deep venous thrombosis (DVT) is a disease caused by abnormal coagulation of blood in the deep veins of the lower extremities. Due to the obstruction of blood return, patients will show symptoms such as swelling, pain and functional impairment of the lower extremities. Once the thrombus breaks off, it may cause pulmonary embolism (PE), resulting in gas exchange disorders, pulmonary hypertension and right heart failure. In severe cases, breathing difficulties, shock and even death may occur. DVT can be treated surgically, and thrombectomy is mainly performed using thrombectomy stents and aspiration catheters. Compared with the use of thrombectomy stents, the use of aspiration catheters has shorter operation time, simpler operation, lower cost, and can avoid the detachment of secondary thrombi, so it has a good application prospect.

[0003] Problems with existing suction catheters include: 1. The catheter is easily blocked: When dealing with large or high-viscosity thrombi in blood vessels, the thrombi are easily blocked at the distal opening of the catheter, resulting in ineffective thrombi aspiration, affecting treatment outcomes and increasing surgical risks; internal catheter blockage: In addition to the distal opening, the interior of the catheter may also be blocked due to the high viscosity or complex composition of the thrombi. 2. Damage during operation: When using a negative pressure suction catheter, improper operation or catheter instability during operation may cause damage to the vessel wall when the catheter moves or rotates within the vessel. Summary of the invention

[0004] The purpose of the present application is to provide an aspiration catheter to improve the problem of thrombus blocking the aspiration catheter and the aspiration catheter damaging the blood vessel.

[0005] The embodiment of the present application is implemented as follows:

[0006] In a first aspect, an embodiment of the present application provides a suction catheter, comprising a catheter, a handle connected to the proximal end of the catheter, and a head portion connected to the distal end of the catheter, wherein the head portion comprises a protective cover and a laparoscopic head disposed inside the protective cover.

[0007] A cable is arranged in the catheter, the cable extends to the distal end of the head end and is fixedly connected to the atherectomy head, and the protective cover is provided with a hollow structure.

[0008] The cable is configured to drive the atherectomy head to rotate, so as to break up the thrombus that enters the protective cover.

[0009] In the above technical solution, the catheter can be inserted into the blood vessels of the human body, and the handle is used for the operator to hold. The hollow structure of the protective cover allows the thrombus to pass through, and then the atherectomy head driven by the cable to rotate will break the thrombus. The size of the thrombus broken by the atherectomy head is small, and it is not easy to cause blockage when the broken thrombus is sucked out; and because the atherectomy head is set in the protective cover, it is not easy to cause damage to the blood vessel. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present application and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without paying creative work.

[0011] Figure 1 A schematic diagram of a suction catheter provided in one embodiment of the present application;

[0012] Figure 2 A schematic diagram of a tip end portion of a suction catheter provided in one embodiment of the present application;

[0013] Figure 3 A schematic diagram of a suction catheter provided in one embodiment of the present application after the protective cover is removed from the tip end;

[0014] Figure 4 A schematic diagram of a rotational atherectomy head provided in one embodiment of the present application;

[0015] Figure 5 A schematic diagram of a rotational atherectomy head provided by an embodiment of the present application at a first viewing angle;

[0016] Figure 6 For this application Figure 5 A schematic diagram of a rotational atherectomy head in a second viewing angle is provided;

[0017] Figure 7 A schematic diagram of a rotational atherectomy head provided by another embodiment of the present application at a first viewing angle;

[0018] Figure 8 For this application Figure 7 A schematic diagram of a rotational atherectomy head in a second viewing angle is provided;

[0019] Fig. 9 A schematic diagram of a rotational atherectomy head provided in another embodiment of the present application at a first viewing angle;

[0020] Fig.10 For this application Fig. 9 A schematic diagram of a rotational atherectomy head in a second viewing angle is provided;

[0021] Fig.11 A schematic diagram of the layer structure of a cable provided in an embodiment of the present application;

[0022] Fig.12 A schematic diagram of the layer structure of the distal end of the catheter provided in an embodiment of the present application;

[0023] Fig.13 It is a schematic diagram of the outer reinforcement layer of the hypotube structure;

[0024] Fig.14 A schematic diagram of the internal structure of a handle provided in an embodiment of the present application;

[0025] Fig.15 An exploded schematic diagram of the handle provided in an embodiment of the present application at the installation position of the spiral mechanism.

[0026] Icons: 01-head end; 02-catheter; 021-main branch; 022-side branch; 03-handle; 04-protective cover; 05-rotary grinding head; 50-cutting blade; 050-connecting part; 051-first cutting blade; 052-second cutting blade; 053-third cutting blade; 054-fourth cutting blade; 501-horizontal cutting part; 502-vertical cutting part; 06-cable; 061-third metal layer; 062-second metal layer; 063-first metal layer; 07-developing ring; 08-control wire; 09-inner reinforcement layer; 10-middle reinforcement layer; 11-outer reinforcement layer; 12-outer tube; 121-side hole; 13-housing; 131-Luer interface; 14-bending and twisting mechanism; 15-screw mechanism; 16-bearing; 17-lining; 18-small bearing. DETAILED DESCRIPTION

[0027] In order to make the purpose, technical solution and advantages of the embodiments of the present application clearer, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, rather than all the embodiments. The components of the embodiments of the present application described and shown in the drawings here can be arranged and designed in various different configurations.

[0028] Therefore, the following detailed description of the embodiments of the present application provided in the accompanying drawings is not intended to limit the scope of the present application for which protection is sought, but merely represents selected embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in the field without creative work are within the scope of protection of the present application.

[0029] The present application embodiment provides a suction catheter, such as Figure 1 As shown, it includes a catheter 02, the proximal end of which is connected to a handle 03, and the distal end of which is connected to a head end 01. Figure 2As shown, the head end 01 includes a protective cover 04 and a pulverizing head 05 disposed inside the protective cover 04. In the present application, the proximal end and the distal end are determined according to the distance from the handle 03. In the same structure, the end closer to the handle 03 is the proximal end, and the end farther from the handle 03 is the distal end. A cable 06 is disposed in the catheter 02, and the cable 06 extends to the distal end of the head end 01 and is fixedly connected to the pulverizing head 05, so that the cable 06 can drive the pulverizing head 05 to rotate. The protective cover 04 is provided with a hollow structure to allow thrombus to pass through, and the thrombus can be broken by the pulverizing head 05 after entering the protective cover 04 through the hollow structure; further, the hollow mechanism on the protective cover 04 is arranged along the circumferential direction of the catheter 02. The suction catheter provided in the present application has the function of breaking up the thrombus, and can more conveniently remove the thrombus; because the protective cover 04 is also provided on the outside of the pulverizing head 05 connected to the distal end of the catheter 02, the pulverizing head 05 is not easy to cause damage to the blood vessel.

[0030] Furthermore, the cable 06 and the protective cover 04 are locked by a structure, and the cable 06 can rotate in the protective cover 04 but cannot move forward and backward; the atherectomy head 05 is fixed around the outer periphery of the cable 06 and cannot move relative to it, and the atherectomy head 05 is driven by the cable 06 to coaxially rotate in the protective cover 04. For example, in some optional embodiments, the cable 06 and the protective cover 04 are connected by a bearing, specifically, the cable 06 is connected to the inner ring of the bearing, and the protective cover 04 is connected to the outer ring of the bearing.

[0031] In some embodiments, Figure 3 and Figure 4 As shown, the atherectomy head 05 has a cutting blade 50, and when the atherectomy head 05 rotates with the cable 06, the blade can break the thrombus. Further, the number of the cutting blades 50 of the atherectomy head 05 is M, and the M cutting blades 50 are arranged along the circumferential direction of the catheter 02; wherein M is a positive integer greater than or equal to 2, so that the cable 06 can break the thrombus at least twice per rotation. Optionally, Figure 3 and Figure 4 The number of cutting blades 50 shown is M=4, Figure 4 The cutting blades 50 are shown to include a first cutting blade 051, a second cutting blade 052, a third cutting blade 053, and a fourth cutting blade 054. Of course, M can also be equal to a positive integer such as 2, 3, 5, 6, etc. In the embodiment where the number of the cutting blades 50 is two or more, the cutting blades 50 are preferably evenly distributed in the circumferential direction of the catheter 02 to reduce the shaking of the atherectomy head 05 during the rotation process.

[0032] For further information, please see Figure 3The cutting blade 50 includes a horizontal cutting portion 501 extending along the axial direction of the catheter 02 and a vertical cutting portion 502 extending along the radial direction of the catheter 02, wherein the axial direction of the catheter 02 is the axial direction of the catheter 02 when the catheter 02 is in a straight state, and the radial direction of the catheter 02 is the direction perpendicular to the axial direction of the catheter 02. One end of the vertical cutting portion 502 is fixedly connected to the proximal end of the horizontal cutting portion 501, and the other end of the vertical cutting portion 502 is fixedly connected to the cable 06. That is, the end of the horizontal cutting portion 501 close to the handle 03 is connected to the cable 06 through the vertical cutting portion 502. During the rotation of the grinding head 05, the horizontal cutting portion 501 and the vertical cutting portion 502 can both achieve the effect of breaking the thrombus. In other embodiments, the horizontal cutting portion 501 may not be parallel to the axial direction of the catheter 02, and the vertical cutting portion 502 may not extend along the radial direction of the tube body.

[0033] In an optional embodiment, please continue to refer to Figure 3 , the lengths of at least two horizontal cutting portions 501 along the axial direction of the catheter 02 are not equal, such as Figure 3 As shown, the cutting blade 50 includes a first cutting blade 051 and a second cutting blade 052, and the lengths of the horizontal cutting portion 501 of the first cutting blade 051 and the horizontal cutting portion 501 of the second cutting blade 052 are not equal. Specifically, the first cutting blade 051 and the second cutting blade 052 are flush on one side close to the distal end and not flush on the other side close to the proximal end; that is, the lengths of the horizontal cutting portions 501 of at least two cutting blades 50 along the axial direction of the catheter 02 are not equal, so that the grinding head 05 can break up thrombi of different sizes.

[0034] In another optional embodiment, Figure 4 As shown, the lengths of at least two vertical cutting portions 502 along the radial direction of the catheter 02 are not equal. Figure 4 As shown, the lengths of the vertical cutting portion 502 of the first cutting blade 051 and the vertical cutting portion 502 of the second cutting blade 052 are not equal; that is, the rotation radius of the first cutting blade 051 and the second cutting blade 052 along the cable 06 is different, so that the grinding head 05 can also break up blood clots of different sizes.

[0035] In an optional embodiment of the present application, Figure 5 , Figure 7 as well as Fig. 9 As shown, the grinding head 05 also includes a connecting portion 050, and the distal ends of the horizontal cutting portions 501 are all connected to the connecting portion 050. Since the distal ends of the horizontal cutting portions 501 are all connected to the connecting portion 050, the distal ends of the horizontal cutting portions 501 are flush, that is, the distal ends of all the cutting blades 50 are at the same position in the axial direction of the catheter 02.

[0036] Optional, Figure 5 , Figure 7 as well as Fig. 9 As shown, the connecting portion 050 includes a hemispherical shell structure 50a, so that the connecting portion 050 rotates together with the cable 06;

[0037] Optional, such as Figure 5 and Fig. 9 As shown, the connecting portion 050 includes a strip structure 50b connected to the shell structure 50a; one end of the strip structure 50b is connected to the shell structure 50a, and the other end extends in a direction perpendicular to the cable 06 and is connected to the distal end of the horizontal cutting portion 501; the setting of the strip structure 50b means that the distal end of the horizontal cutting portion 501 is retracted in the direction of the cable 06, thereby preventing the horizontal cutting portion 501 from rotating to cut the thrombus and hitting the protective cover 04.

[0038] Optional, please continue to see Figure 7 as well as Fig. 9 , the distal ends of the M horizontal cutting parts 501 are flush (for example, the distal ends of the horizontal cutting parts 501 of all the cutting blades 50 are connected to the connecting part 050), and the vertical cutting parts 502 connected to the M horizontal cutting parts 501 are connected to different positions on the cable 06, that is, the lengths of all the horizontal cutting parts 501 in the axial direction of the catheter 02 are different, which means that all the corresponding vertical cutting parts 502 are not in the same plane, and the M vertical cutting parts 502 correspond to M planes perpendicular to the cable 06. Therefore, when the grinding head 05 rotates, the thrombus sucked into the catheter 02 can be broken up by the M vertical cutting parts 502 at the M planar positions in the axial direction of the catheter 02, forming the effect of M consecutive thrombus breaking up, thereby achieving the function of strengthening the thrombus breaking by multiple thrombus breaking in the axial direction.

[0039] In an optional embodiment, if Fig. 9 As shown, in an embodiment where the lengths of the horizontal cutting portion 501 in the axial direction of the catheter 02 are different, the distal ends of the horizontal cutting portion 501 are flush, and the distance d1 between any two adjacent vertical cutting portions 502 in the axial direction of the cable 06 is equal; accordingly, the size of the thrombus that can be broken by each cutting blade 50 in the axial direction of the cable 06 gradually increases.

[0040] In another optional embodiment, if Fig. 9 As shown, in an embodiment where the distal ends of the horizontal cutting portions 501 are flush and the lengths of the horizontal cutting portions 501 in the axial direction of the catheter 02 are different, the spacing d2 between two vertical cutting portions 502 opposite to each other in the circumferential direction of the catheter 02 in the axial direction of the catheter 02 may be equal.

[0041] For example, the first vertical cutting portion 502, the second vertical cutting portion 502, the third vertical cutting portion 502 and the fourth vertical cutting portion 502 are sequentially distributed in the circumferential direction of the conduit 02; wherein the first vertical cutting portion 502 and the third vertical cutting portion 502 are arranged opposite to each other, and the second vertical cutting portion 502 and the fourth vertical cutting portion 502 are arranged opposite to each other; the spacing between the first vertical cutting portion 502 and the second vertical cutting portion 502 along the axial direction of the conduit 02 is d1, the spacing between the second vertical cutting portion 502 and the third vertical cutting portion 502 along the axial direction of the conduit 02 is d1, and the spacing between the third vertical cutting portion 502 and the fourth vertical cutting portion 502 along the axial direction of the conduit 02 is d1. Optionally, the spacing between the first vertical cutting portion 502 and the third vertical cutting portion 502 along the axial direction of the conduit 02 is d2, and the spacing between the second vertical cutting portion 502 and the fourth vertical cutting portion 502 along the axial direction of the conduit 02 is d2; wherein d2=2d1.

[0042] In some embodiments, the spacing between any two adjacent vertical cutting portions 502 in the axial direction of the cable 06 may be equal, and the spacing between any two vertical cutting portions 502 opposite to each other in the circumferential direction of the catheter 02 may be equal along the axial direction of the catheter 02.

[0043] In an optional embodiment of the present application, Figure 6 and Fig.10 As shown, the atherectomy head 05 includes a plurality of cutting blades 50, and the lengths of the vertical cutting portions 502 of at least two cutting blades 50 along the radial direction of the catheter 02 are not equal (e.g. Fig.10 As shown, L2>L1); in some embodiments, the lengths of the vertical cutting portions 502 of all the cutting blades 50 along the radial direction of the catheter 02 are not equal, that is, one end of the M vertical cutting portions 502 is fixedly connected to the cable 06, and the lengths of the other ends from the cable 06 are different. Correspondingly, the distances of the horizontal cutting portions 501 connected to the vertical cutting portions 502 from the cable 06 are also different. In this way, the M cutting blades 50 have M horizontal cutting portions 501 to form M rotating surfaces. The thrombus sucked into the catheter 02 can be broken up on the M rotating surfaces by the M horizontal cutting portions 501, forming an effect of breaking up the thrombus M times continuously, so as to achieve the breaking up of thrombi of more sizes.

[0044] Optional, such as Figure 6 and Fig.10 As shown, the lengths of the vertical cutting portions 502 increase at equal intervals, that is, the lengths of all the vertical cutting portions 502 can form an arithmetic progression. Optionally, in the circumferential direction of the catheter 02, the lengths of the vertical cutting portions 502 increase at equal intervals in sequence. Specifically, refer to Fig.10The lengths of the vertical cutting portions 502 are L1, L2, L3, and L4, respectively, wherein L4-L3=L3-L2=L2-L1. In other implementations, the lengths of the vertical cutting portions 502 may also be set according to other rules, or may be set irregularly.

[0045] Optionally, the spacing between two vertical cutting portions 502 that are opposite to each other in the circumferential direction of the catheter 02 and in the axial direction of the catheter 02 is equal.

[0046] In one embodiment of the present application, the length of the horizontal cutting portion 501 and the length of the vertical cutting portion 502 of the cutting blade 50 do not affect each other. In an optional embodiment, as shown in FIG. Figure 5 and Figure 6 As shown, the horizontal cutting parts 501 of the four cutting blades 50 in the atherectomy head 05 are equal in length along the axial direction of the catheter 02, but the vertical cutting parts 502 of the cutting blades 50 are not equal in length along the radial direction of the catheter 02. In this way, the M cutting blades 50 have M horizontal cutting parts 501 to form M rotating curved surfaces, and the thrombus sucked into the catheter 02 can be broken on the M rotating curved surfaces by the M horizontal cutting parts 501, forming the effect of breaking the thrombus continuously for M times.

[0047] In another optional embodiment of the present application, Figure 7 and Figure 8 As shown, the lengths of the horizontal cutting parts 501 of the four cutting blades 50 in the atherectomy head 05 along the axial direction of the catheter 02 are not equal, but the lengths of the vertical cutting parts 502 of the cutting blades 50 along the radial direction of the catheter 02 are equal. This means that all the corresponding vertical cutting parts 502 are not in the same plane, and M vertical cutting parts 502 correspond to M planes perpendicular to the cable 06. Therefore, when the atherectomy head 05 rotates, the thrombus sucked into the catheter 02 can be broken by the M vertical cutting parts 502 at M plane positions on the axial direction of the catheter 02, forming the effect of M times of continuous thrombus breaking, so that the function of strengthening the thrombus breaking is achieved by multiple thrombus breaking in the axial direction.

[0048] In another optional embodiment of the present application, Fig. 9 and Fig.10 As shown, the lengths of the horizontal cutting parts 501 of the four cutting blades 50 in the atherectomy head 05 along the axial direction of the catheter 02 are all unequal, and the lengths of the vertical cutting parts 502 of the cutting blades 50 along the radial direction of the catheter 02 are all unequal. In this way, the thrombus sucked into the catheter 02 can be broken up on the M rotating curved surfaces by the M horizontal cutting parts 501, forming the effect of breaking up the thrombus M times continuously, and can also be broken up by the M vertical cutting parts 502, forming the effect of breaking up the thrombus M times continuously.

[0049] In some embodiments, Figure 5 , Figure 7 and Fig. 9 As shown, the horizontal cutting portion 501 has a cutting surface T, and the cutting surface T on at least one side in the circumferential direction of the catheter 02 has a cutting edge, and the cutting edge is a wavy tooth structure. That is, the cutting surface T on one side in the circumferential direction of the catheter 02 may have a cutting edge, or the cutting surfaces T on both sides in the circumferential direction of the catheter 02 may have cutting edges. In the embodiment in which the cutting surfaces T on both sides in the circumferential direction of the catheter 02 have cutting edges, the atherectomy head 05 can effectively break up the thrombus during both forward and reverse rotation. The cutting edge of the wavy tooth structure has a sharp tip, and during the rotation of the atherectomy head 05, the cutting edge of the wavy tooth structure can better break up the thrombus. In other embodiments, the cutting edge may also be a structure of other shapes, such as a broken line shape.

[0050] For example, Fig. 9 , Fig.10 As shown, one cutting blade 50 is referred to as the first cutting blade 051 and the other cutting blade 50 is referred to as the second cutting blade 052; the length of the horizontal cutting portion 501 of the first cutting blade 051 is L11, the length of the horizontal cutting portion 501 of the second cutting blade 052 is L21, the length of the vertical cutting portion 502 of the first cutting blade 051 is L12, and the length of the vertical cutting portion 502 of the second cutting blade 052 is L22; wherein, L11>L21, L12>L22.

[0051] In the present application embodiment, Fig.10 As shown, when the horizontal cutting portion 501 in the cutting blade 50 is set longer, the vertical cutting portion 502 is also set longer. This design makes it possible for the connected horizontal cutting portion 501 to be the longest when the vertical cutting portion 502 is the longest, such as when one of the cutting blades 051 (50) is set in the outermost layer; when the vertical cutting portion 502 is the shortest, the connected horizontal cutting portion 501 is also the shortest, such as when another of the cutting blades 052 (50) is set in the innermost layer. By reasonably matching and combining the lengths of the vertical cutting portion 502 and the horizontal cutting portion 501, the rotating curved surfaces where the multiple horizontal cutting portions 501 are located and the rotating planes where the multiple vertical cutting portions 502 are located can be fully utilized to fully and multiple times break up the thrombus sucked into the grinding head 05.

[0052] In some embodiments, Fig.11As shown, the cable 06 includes a first metal layer 063 disposed on the outer layer and a second metal layer 062 disposed on the inner layer; the first metal layer 063 includes N1 first metal wires spirally wound in a first direction, and the second metal layer 062 includes N2 second metal wires spirally wound in a second direction, and the first direction and the second direction are opposite. The cable 06 structure provided in this embodiment can make the flexibility of the cable 06 unaffected and have a larger torque, so that in a tortuous blood vessel, the cable 06 can better drive the atherectomy head 05 to rotate to more effectively crush the thrombus.

[0053] In some implementations, N1=N2, and in other implementations, N1>N2.

[0054] Furthermore, in some embodiments, the diameter of the first metal wire is equal to the diameter of the second metal wire; in other embodiments, the diameter of the first metal wire may be greater than the diameter of the second metal wire.

[0055] Alternatively, if Fig.11 As shown, the cable 06 also includes a third metal layer 061 located inside the second metal layer 062, the third metal layer 061 includes a third metal wire, and the second metal wire is distributed along the circumference of the third metal wire. That is, the second metal wire in the second metal layer 062 is distributed along the circumference and surrounds the third metal wire inside. Further, in some embodiments, the diameter of the first metal wire can be equal to the diameter of the third metal wire, or it can be greater than the diameter of the third metal wire. Optionally, the diameter of the third metal wire is equal to the diameter of the first metal wire, so that the cable 06 as a whole has better torque performance.

[0056] Optionally, when N1=N2 or N1<N2, the diameter of the first metal wire in the outer layer is larger than the diameter of the second metal wire in the inner layer, or when the diameter of the first metal wire in the outer layer is equal to the diameter of the second metal wire in the inner layer, N1>N2, so that the cable 06 has stronger torque performance.

[0057] Furthermore, the first metal wire, the second metal wire and the third metal wire may be stainless steel structures, nickel-titanium structures or tungsten structures, and the materials of the first metal wire, the second metal wire and the third metal wire may be the same or different.

[0058] In some embodiments, Fig.12 , 14 and Fig.15As shown, the handle 03 includes a shell 13 and a bending adjustment knob 14 slidably connected to the shell 13; a developing ring 07 is provided at the distal end of the catheter 02, and a control wire 08 is provided inside the catheter 02. One end of the control wire 08 is fixedly connected to the developing ring 07, and the other end is fixed to the bending adjustment knob 14. Pushing the bending adjustment knob 14 pulls the control wire 08 to drive the distal end of the catheter 02 where the developing ring 07 is located to bend.

[0059] Optionally, in some embodiments, Fig.15 As shown, the proximal side branch 022 of the catheter 02 is provided with a Luer interface 131, which provides negative pressure to the space in the protective cover 04 by connecting to the negative pressure suction device, thereby achieving the thrombus suction function. Of course, in other embodiments, the proximal side branch 022 of the catheter 02 may also adopt other forms of interfaces; or the interface may be provided at other positions of the catheter 02.

[0060] Optionally, in some embodiments, Fig.15 As shown, the handle 03 further includes a spiral mechanism 15 and a bearing 16, and the cable 06 extends through the proximal end of the catheter 02 and is welded to the spiral mechanism 15 through the bearing 16; the cable 06 also passes through the handle 03 and extends to the distal end of the catheter 02 and is connected to the atherectomy head 05. The rotation of the spiral mechanism 15 can drive the cable 06 to rotate, thereby driving the atherectomy head 05 to rotate coaxially.

[0061] Further, if Fig.14 and Fig.15 As shown, the cable 06 led out from the main branch 021 at the proximal end of the catheter 02 is welded to the spiral mechanism 15 through the bearing 16 and the small bearing 18. The small bearing 18 blocks the proximal opening of the main branch 021 of the catheter 02 and does not affect the rotation of the cable 06. The spiral mechanism 15 is connected to an external electric spiral device. When the spiral mechanism 15 rotates, it can drive the grinding head 05 to rotate coaxially through the cable 06 to crush the thrombus.

[0062] In some embodiments, Fig.12 and Fig.13 As shown, the catheter 02 includes an inner lining 17, an inner reinforcement layer 09, an intermediate reinforcement layer 10 and an outer tube 12 from the inside to the outside; the inner reinforcement layer 09 and the intermediate reinforcement layer 10 include any one of a braided structure, a coiled spring structure, and a hypotube structure.

[0063] The inner liner 17 can be a PTFE (polytetrafluoroethylene) structural part. PTFE is a self-lubricating polymer material. The smooth inner cavity reduces the friction between the thrombus and the inner cavity, and reduces the probability of thrombus stuck in the lumen during surgery. The inner reinforcement layer 09 can be a braided or spring-wound or laser-cut hypotube structure, and the material can be stainless steel, tungsten wire or nickel-titanium alloy; therefore, the pressure resistance of the catheter 02 can be increased to prevent the catheter 02 from being crushed when the thrombus is aspirated.

[0064] Furthermore, the developing ring 07 is fixed at the distal end of the liner 17 to assist the operator in accurately determining the position of the distal end of the catheter 02 under DSA (Digital Subtraction Angiography).

[0065] Furthermore, the middle reinforcement layer 10 can be a braided or spring wound or laser cut hypotube structure, and the material can be stainless steel, tungsten wire or nickel titanium alloy. The control wire 08 is fixed outside the inner reinforcement layer 09, and the control wires 08 on both sides are 180 degrees. The far end of the control wire 08 is fixed on the developing ring 07 by welding. That is, two relative positions on the circumference of the developing ring 07 are each welded with a control wire 08.

[0066] Two control wires 08 welded to the developing ring 07 are led out from the proximal side incision and respectively connected to the left and right bending adjustment knobs 14. When the catheter 02 needs to be delivered into the blood vessel branch, the left / right bending adjustment knobs 14 are pushed and pulled through the angle of the DSA blood vessel to gradually bend the distal end of the catheter 02 to adapt to the curved part of the blood vessel, and the catheter 02 is pushed into the target blood vessel smoothly to achieve guidewire-free operation.

[0067] Furthermore, the material hardness of the outer tube 12 gradually transitions from the proximal end to the distal end, that is, the distal end of the outer tube 12 is softer and the proximal end is harder, so as to facilitate the bending of the distal end of the catheter 02. The outer tube 12 can be prepared by a thermo-rheological process.

[0068] Optionally, in some embodiments, an outer reinforcement layer 11 is further provided between the middle reinforcement layer 10 and the outer tube 12. The outer reinforcement layer 11 is a braided structure or a spring structure or a hypotube structure, and the material can be stainless steel, tungsten wire or nickel-titanium alloy. The outer reinforcement layer 11 is intended to further improve the product's twist control and push performance. The design without the outermost layer is also within the scope of the present invention. The attached figure of this embodiment shows the structure of three reinforcement layers, namely, the inner reinforcement layer 09, the middle reinforcement layer 10 and the outer reinforcement layer 11; but in other embodiments, only the inner reinforcement layer 09 and the middle reinforcement layer 10 may be provided.

[0069] In some embodiments of the present application, Fig.13 As shown, the hypotube structure is a clockwise spiral notch structure, which is divided into three sections with different pitches, and the pitch of the notch gradually decreases from the handle 03 to the distal end. Specifically, when the hollow gaps of the notch are equal, the density of the hollow gaps at the distal end is larger, and the density of the hollow gaps at the handle 03 is smaller, that is, the distance between two adjacent hollow gaps of the hypotube near the head end is reduced, so as to ensure that the proximal end of the catheter 02 has a stronger pushability and the distal end has a higher flexibility, which helps the catheter 02 to pass through the tortuous blood vessels more easily.

[0070] In some embodiments, Figure 3 As shown, the outer tube 12 is also provided with an axially extending side hole 121, and the side hole 121 is provided with an opening at one end of the outer tube 12 close to the head end 01, that is, the catheter 02 is also provided with a side hole 121 for spraying contrast agent, and the opening of the side hole 121 is located at the distal end of the catheter 02.

[0071] In the process of using the suction catheter 02 provided in the embodiment of the present application to clean the thrombus, when the distal end of the catheter 02 approaches the thrombus, the thrombus is adsorbed to the hollow structure of the protective cover 04 by the negative pressure provided by the proximal end, and the grinding head 05 rotates at high speed driven by the spiral mechanism 15 and the cable 06 to break up the thrombus, so as to prevent the thrombus with a large diameter or old thrombus from blocking the catheter 02. The broken thrombus passes through the catheter 02 under the action of negative pressure, is drawn out of the blood vessel, and the blood flow in the blood vessel is restored. The contrast agent can be injected through the side hole 121 of the catheter 02, and the position of the thrombus in the blood vessel and the postoperative blood flow can be monitored by DSA, and the position of the distal end of the catheter 02 can also be accurately determined by DSA.

[0072] The above are only preferred embodiments of the present application and are not intended to limit the present application. For those skilled in the art, the present application may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A suction catheter, characterized in that: It comprises a catheter, a handle connected to the proximal end of the catheter, and a head end connected to the distal end of the catheter, wherein the head end comprises a protective cover and a laparotomy head arranged inside the protective cover; A cable is arranged in the catheter, the cable extends to the distal end of the head end and is fixedly connected to the atherectomy head, and the protective cover is provided with a hollow structure; The cable is configured to drive the atherectomy head to rotate, so as to break up the thrombus that enters the protective cover.

2. The suction catheter according to claim 1, characterized in that The atherectomy head comprises M cutting blades arranged along the circumferential direction of the catheter, where M is a positive integer greater than or equal to 2; optionally, M=4; The cutting blade comprises a horizontal cutting portion extending in the axial direction of the catheter and a vertical cutting portion extending in the radial direction of the catheter, one end of the vertical cutting portion is fixedly connected to the proximal end of the horizontal cutting portion, and the other end of the vertical cutting portion is fixedly connected to the cable; The lengths of at least two of the horizontal cutting portions along the axial direction of the catheter are unequal; and / or, The lengths of at least two of the vertical cutting portions along the radial direction of the catheter are unequal.

3. The suction catheter according to claim 2, characterized in that The atherectomy head further comprises a connecting portion, and the distal ends of the horizontal cutting portions are all connected to the connecting portion; the lengths of at least two of the horizontal cutting portions along the axial direction of the catheter are unequal; The distal ends of the M horizontal cutting portions are flush with each other, and the vertical cutting portions correspondingly connected to the M horizontal cutting portions are connected to different positions on the cable.

4. The suction catheter according to claim 3, characterized in that The distance between any two adjacent vertical cutting portions in the axial direction of the cable is equal; and / or, The distances between the two vertical cutting portions opposite to each other in the circumferential direction of the catheter are equal along the axial direction of the catheter.

5. The suction catheter according to claim 3, characterized in that: The horizontal cutting portion has a cutting surface, and the cutting surface on at least one side in the circumferential direction of the catheter has a cutting edge, and the cutting edge is a wave tooth structure.

6. The suction catheter according to claim 2, characterized in that: The lengths of at least two of the vertical cutting portions along the radial direction of the catheter are unequal; One end of the M vertical cutting portions is fixedly connected to the cable, and the other end has a different distance from the cable.

7. The suction catheter according to claim 6, characterized in that Note that one of the cutting blades is a first cutting blade, and the other of the cutting blades is a second cutting blade; The length of the horizontal cutting portion of the first cutting blade is L11, the length of the horizontal cutting portion of the second cutting blade is L21, the length of the vertical cutting portion of the first cutting blade is L12, the length of the vertical cutting portion of the second cutting blade is L22, Among them, L11>L21, L12>L22.

8. The suction catheter according to claim 1, characterized in that The cable comprises a first metal layer arranged on an outer layer and a second metal layer arranged on an inner layer; the first metal layer comprises N1 first metal wires spirally wound in a first direction, and the second metal layer comprises N2 second metal wires spirally wound in a second direction, and the first direction is opposite to the second direction; Optionally, the diameter of the first metal wire is equal to the diameter of the second metal wire; Optionally, the cable further includes a third metal layer located inside the second metal layer, the third metal layer includes a third metal wire, and the second metal wire is distributed along the circumference of the third metal wire.

9. The suction catheter according to claim 1, characterized in that: The handle comprises a shell and a bending adjustment knob slidably connected to the shell; a developing ring is arranged at the distal end of the catheter, a control wire is arranged in the catheter, one end of the control wire is fixedly connected to the developing ring, and the other end is fixed to the bending adjustment knob, and the bending adjustment knob is pushed to pull the control wire to bend the distal end of the catheter where the developing ring is located; and / or, The proximal side branch of the catheter is provided with a Luer interface, and the Luer interface provides negative pressure for the space in the protective cover by connecting to a negative pressure suction device; and / or, The handle further comprises a spiral mechanism and a bearing. The cable extends out of the proximal end of the catheter and is welded to the spiral mechanism through the bearing. The rotation of the spiral mechanism can drive the cable to rotate, thereby driving the atherectomy head to rotate coaxially.

10. The suction catheter according to claim 1, characterized in that The catheter comprises an inner lining, an inner reinforcement layer, an intermediate reinforcement layer and an outer tube from the inside to the outside; the inner reinforcement layer and the intermediate reinforcement layer comprise any one of a braided structure, a coiled spring structure and a hypotube structure; And / or, an outer reinforcement layer is further provided between the intermediate reinforcement layer and the outer tube, and the outer reinforcement layer is a braided structure or a spring wound structure or a hypotube structure; And / or, the outer tube is further provided with an axially extending side hole, and the side hole is provided with an opening at one end of the outer tube close to the head end.

Images