Medical cutting device and suite

Abstract

The invention provides a medical cutting device and a kit. The medical cutting device comprises a base body and a cutting part, the base body is provided with an inner cavity extending in the axial direction of the base body in a penetrating mode. The cutting part is arranged on the peripheral surface of the base body; the base body is configured to expand in the radial direction when the base body is subjected to acting force outwards in the radial direction, and contract in the radial direction when the acting force is canceled. And a recess for accommodating the cutting part is formed in the part, where the cutting part is arranged, of the base body in the radial contraction state. The cutting assembly in the radial contraction state has a small outer diameter, can adapt to treatment of small vasculopathy, is easier to advance in the blood vessel and penetrates tortuous and narrow parts of the blood vessel.

Description

Technical Field

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

[0002] For moderate to severe calcification and plaque lesions in peripheral vessels and coronary arteries, balloon catheters with cutting functions are usually used for treatment.

[0003] A traditional balloon catheter with a cutting function has cutting elements such as metal wires, blades, and saw teeth arranged on the outer circumference of the balloon body, and the lesion is cut by the cutting elements. This type of balloon catheter has many problems in actual use. For example, the presence of the cutting element causes the balloon catheter to still have a large outer diameter after being squeezed and gripped, making it unfriendly to small blood vessels with smaller diameters and reducing the bending performance. On the other hand, it also increases the local weight of the balloon catheter, which causes the user to apply a pushing force to the push rod of the balloon catheter (generally a polymer tube) to push the balloon catheter. The loss of the pushing force is too large, further reducing the bending performance of the balloon catheter. For example, since the cutting element is directly arranged on the outer circumference of the balloon body, when the cutting element is positioned by rotation and other operations, the cutting element is prone to cause unnecessary damage to the inner wall of the blood vessel, affecting the treatment effect.

[0004] In response to the problems existing in traditional balloon catheters with cutting functions, medical device manufacturers have proposed alternative medical devices, such as the XO-Score cutting sheath proposed by Transit Scientific, which is formed by cutting and shaping a tube and includes a plurality of cutting blades arranged in sequence along its circumference, and the cutting blades are formed after the tube is cut. The cutting sheath is used in conjunction with the balloon. When in use, the cutting sheath is sleeved on the outer circumference of the balloon and can slide along the outer circumference of the balloon. When the balloon is in a compressed state, each cutting blade extends along the circumference of the cutting sheath when viewed from the cross section of the cutting sheath (i.e., the cross section perpendicular to the axial direction of the cutting sheath). When the balloon is filled, the cutting sheath expands and causes the cutting blade to rotate 90°, so that each cutting blade extends radially along the cutting sheath when viewed from the cross section of the cutting sheath, so as to cut calcification and plaque lesions. Compared with traditional balloons with cutting functions, its outer diameter during delivery is relatively small, and it is not easy to damage the blood vessel wall during positioning. However, it still has some problems. For example, after the balloon is filled and the cutting blade rotates 90°, the contact area between the cutting blade and the outer peripheral surface of the balloon is reduced and the pressure is increased. While the cutting element applies focal force to the narrow part of the blood vessel, it also exerts an opposite force on the balloon, which poses a risk of damaging the balloon. In addition, each cutting blade extends continuously along the axial direction of the cutting sheath, resulting in a larger rigidity of the cutting sheath and difficulty in bending, which is not conducive to the cutting sheath moving in tortuous blood vessels. Summary of the invention

[0005] The object of the present invention is to provide a medical cutting device and a kit, aiming to reduce the outer diameter of the medical cutting device in a radially contracted state and improve the applicability of the medical cutting device and the kit to small blood vessels.

[0006] To achieve the above object, the present invention provides a medical cutting device, comprising a base body and a plurality of cutting parts; the base body has an inner cavity extending through the base body along its axial direction; the cutting parts are arranged on the outer peripheral surface of the base body;

[0007] The base is configured to expand radially when subjected to a radially outward force, and to contract radially when the force is canceled; when the base is in a radially contracted state, a portion of its outer circumferential surface where the cutting portion is provided forms a recess for accommodating the cutting portion.

[0008] Optionally, all the cutting portions are arranged at intervals along the circumference of the base body, and each of the cutting portions extends continuously along the axial direction of the base body.

[0009] Optionally, all the cutting parts are divided into a plurality of cutting part groups, each of which includes a plurality of cutting parts; all the cutting part groups are arranged at intervals along the circumference of the base, and all the cutting parts in the same cutting part group are arranged at intervals along the axial direction of the base.

[0010] Optionally, the recess is U-shaped in a cross section of the base.

[0011] Optionally, the cutting device further comprises a developing element; each of the developing elements is arranged on the substrate and located between two adjacent cutting parts.

[0012] Optionally, the substrate comprises a first proximal connecting portion, a main body portion and a first distal connecting portion which are connected in sequence; and the cutting portion is arranged on the main body portion.

[0013] Optionally, the main body portion includes a plurality of main body coupling rings and a plurality of main body connecting wires; all of the main body coupling rings are arranged at intervals along the axial direction of the base, and the main body coupling ring located at the nearest end is connected to the first proximal connecting portion, and the main body coupling ring located at the farthest end is connected to the first distal connecting portion; all of the main body connecting wires are arranged at intervals along the circumferential direction of the base; each of the main body coupling rings is connected to all of the main body connecting wires, and each of the main body connecting wires is connected to all of the main body coupling rings; each of the cutting portions is arranged at the junction of a main body coupling ring and a main body connecting wire.

[0014] Optionally, when the base is in the radially contracted state, at least one first wavy structure is formed on the main body coupling ring, and the crests and troughs of the first wavy structure are alternately arranged along the circumference of the base, and one of the crests and troughs of the first wavy structure is toward the first proximal connecting part, and the other is toward the first distal connecting part; the first wavy structure and the recess are staggered in the circumference of the base.

[0015] Optionally, when the base is in the radially contracted state, at least one second wavy structure is formed on the main connecting wire, and the crests and troughs of the second wavy structure are alternately arranged in the axial direction of the base; the crests and troughs of the second wavy structure are relatively arranged along the circumference of the base on the axial projection of the main body.

[0016] Optionally, the medical cutting device further comprises a push rod, the push rod comprising a rod body and a hydrophilic coating optionally provided on the outer peripheral surface of the rod body, the distal end of the push rod is connected to the proximal end of the substrate.

[0017] Optionally, when the base changes from a contracted state to an expanded state, the radially outward expansion distance of the recess is greater than the radially outward expansion distance of other parts of the base.

[0018] To achieve the above-mentioned purpose, the present invention also provides a medical cutting kit, comprising a balloon catheter and the medical cutting device as described above, wherein the balloon catheter comprises a tube assembly and a balloon body arranged on the distal end of the tube assembly, and the medical cutting device is used to be sleeved on a portion of the outer circumference of the balloon catheter, and allows the balloon body to be detachably inserted into the inner cavity of the base.

[0019] Optionally, the balloon body comprises a second proximal connecting portion, a straight portion and a second distal connecting portion connected in sequence;

[0020] The total length of the cutting portion in the axial direction of the medical cutting kit is 2 / 3 to 3 / 4 of the axial length of the straight portion.

[0021] Compared with the prior art, the medical cutting device and kit of the present invention have the following advantages:

[0022] The aforementioned medical cutting device comprises a base and a blade; the base has an inner cavity extending through the axial direction thereof, and the cutting portion is arranged on the outer peripheral surface of the base; the base is configured to expand radially when it is subjected to a radially outward force, and to contract radially when the force is cancelled; when the base is in a radially contracted state, the portion of the base where the cutting portion is arranged forms a depression for accommodating the cutting portion. That is, when the base is in the radially contracted state, the cutting portion is located in the depression and does not protrude from the base, which, on the one hand, enables the cutting device in the radially contracted state to have a smaller outer diameter, thereby enabling the cutting device to be applied to blood vessels with smaller diameters and having better passability, so that when the distal end of the cutting device is delivered to the blood vessel, it can more easily pass through the narrow part and the curved part of the blood vessel. On the other hand, it is also ensured that no damage is caused to the blood vessel wall during the process of delivering the cutting device and positioning the distal end of the cutting device.

[0023] The medical cutting kit includes the medical cutting device and a balloon catheter, the balloon catheter includes a tube assembly and a balloon body disposed at the distal end of the tube assembly, the portion of the balloon catheter where the balloon body is disposed is used to be detachably disposed in the inner cavity of the base, and the medical cutting kit is configured to apply a radially outward force to the base through the balloon body in a filled state, so that the base switches from a radially contracted state to a radially expanded state. The cutting portion is connected to the base, and even if the base expands under the action of the balloon body, the cutting portion does not directly contact the balloon body, and the two are isolated by the base, so that the cutting portion will not cause damage to the balloon body, and the problem of failure of the base expansion caused by pressure relief due to balloon damage will not occur. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] The accompanying drawings are used to better understand the present invention and do not constitute an improper limitation of the present invention.

[0025] Figure 1 is a schematic structural diagram of a medical cutting device provided according to an embodiment of the present invention, wherein the base body is in a radially contracted state;

[0026] Figure 2 yes Figure 1 AA cross-sectional view of the medical cutting device shown;

[0027] Figure 3 is a schematic structural diagram of a medical cutting device provided according to an embodiment of the present invention, wherein the base body is in a state where it receives radially outward force but is not fully expanded;

[0028] Figure 4is a cross-sectional view of a medical cutting device provided according to an embodiment of the present invention, in which the base is fully expanded;

[0029] Figure 5 is a schematic structural diagram of a base body of a medical cutting device provided according to an embodiment of the present invention, in which the base body is in an incompletely expanded state;

[0030] Figure 6 Schematic diagram of a blade of a medical cutting device provided according to an embodiment of the present invention, wherein the blade shown in a) is trapezoidal, the blade shown in b) is rectangular, and the blade shown in c) is serrated;

[0031] Figure 7 is a schematic structural diagram of a balloon catheter of a medical cutting kit provided according to an embodiment of the present invention;

[0032] Figure 8 is a structural schematic diagram of a medical cutting kit provided according to an embodiment of the present invention, in which the balloon body is not filled and the base body is in a radially contracted state;

[0033] Fig. 9 yes Figure 8 BB cross-sectional view of the medical cutting kit shown;

[0034] Fig.10 is a schematic structural diagram of a medical cutting kit provided according to an embodiment of the present invention, in which the balloon body is not fully filled and the base body is in an incompletely expanded state;

[0035] Fig.11 1 is a cross-sectional view of a medical cutting kit provided according to an embodiment of the present invention, in which the balloon is filled and the base is fully expanded.

[0036] [Description of reference numerals is as follows]:

[0037] 10-medical cutting kit, 100-medical cutting device, 200-balloon catheter, 300-guide wire, 1000-cutting assembly, 1100-base, 1101-recess, 1110-first proximal connecting portion, 1111-proximal connecting wire, 1111a-third wavy structure, 1112-proximal coupling ring, 1120-main body, 1121-main body coupling ring, 1121a-first wavy structure, 1122-main body connecting wire, 1122a-second wavy structure , 1130-first distal connection part, 1131-distal connection wire, 1131a-fourth wavy structure, 1132-distal coupling ring, 1200-cutting part, 1300-first developing element, 2000-pushing rod, 3000-tube assembly, 3100-inner tube, 3200-outer tube, 4000-balloon body, 4100-second proximal connection part, 4200-straight part, 4300-second distal connection part, 5000-second developing element, 6000-guide head. DETAILED DESCRIPTION

[0038] The following is an explanation of the embodiments of the present invention by specific examples, and those skilled in the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and the details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present invention. It should be noted that the illustrations provided in the present embodiment only illustrate the basic concept of the present invention in a schematic manner, and only the components related to the present invention are shown in the figure instead of being drawn according to the number, shape and size of the components in the actual implementation. The type, quantity and proportion of each component in the actual implementation can be a random change, and the component layout type may also be more complicated.

[0039] In addition, each embodiment of the following description has one or more technical features, but this does not mean that the user of the present invention must implement all the technical features in any embodiment at the same time, or can only implement part or all of the technical features in different embodiments separately. In other words, under the premise that implementation is possible, those skilled in the art can selectively implement part or all of the technical features in any embodiment according to the disclosure of the present invention and according to the design specifications or implementation requirements, or selectively implement a combination of part or all of the technical features in multiple embodiments, thereby increasing the flexibility of the implementation of the present invention.

[0040] As used in this specification, the singular forms "one", "an", and "the" include plural objects, and the plural form "a plurality" includes more than two objects, unless the content clearly indicates otherwise. As used in this specification, the term "or" is generally used in a sense that includes "and / or", unless the content clearly indicates otherwise, and the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection. It can be a mechanical connection or an electrical connection. It can be directly connected or indirectly connected through an intermediate medium, and it can be a connection between two elements or an interactive relationship between two elements. Relational terms such as the terms "first", "second", etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations, nor do they indicate or imply relative importance or implicitly indicate the number of technical features indicated. It should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "axial", "radial", "circumferential" and the like indicate positions or position relationships based on the positions or position relationships shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific position, be constructed and operated in a specific position, and therefore cannot be understood as limiting the present invention. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0041] The terms "distal end" and "proximal end" used in this article are used to describe the relative positions and orientations of the various parts and components of the medical device. Although non-restrictive, the "distal end" is usually the end of the medical device that first enters the patient's body during normal use, and the "proximal end" is the end opposite to the "distal end", that is, the "proximal end" is closer to the operator.

[0042] The purpose of the present invention is to provide a medical cutting device, which can be used in conjunction with a balloon catheter to cut and treat calcified and plaque-diseased tissues in blood vessels and dilate the blood vessels. The cutting device has a smaller outer diameter in a compressed state, and can easily move in the blood vessels and pass through the narrowed parts.

[0043] In order to make the purpose, advantages and features of the present invention more clear, the present invention is further described in detail below with reference to the accompanying drawings. It should be noted that the drawings are all in very simplified form and in non-precise proportions, and are only used to conveniently and clearly assist in explaining the purpose of the embodiments of the present invention. The same or similar reference numerals in the drawings represent the same or similar components.

[0044] Figure 1 and Figure 3 FIG. 1 is a schematic diagram showing the structure of the medical cutting device 100. Figure 2 A cross-sectional view showing the medical cutting device in a radially compressed state, Figure 4 A cross-sectional view of the medical cutting device in a radially expanded state is shown. Figures 1 to 4 The medical cutting device 100 includes a base 1100 and a cutting part 1200. The base 1100 has an inner cavity extending through the base 1100 along its axial direction, and the cutting part 1200 is arranged on the outer peripheral surface of the base 1100. Hereinafter, the base 1100 and the components arranged thereon are collectively referred to as a cutting assembly 1000, so that the cutting assembly 1000 at least includes the cutting part 1200. The cutting assembly 1000 is used to be transported and positioned at a target position in a blood vessel to cut calcified tissue and / or plaque tissue and achieve dilation of the blood vessel.

[0045] The base 1100 is configured to expand radially when it is subjected to a radially outward force, and to contract radially when the force is canceled. In other words, the base 1100 has a radially expanded state and a radially contracted state. It should be understood that the state of the cutting assembly 1000 is the same as the state of the base 1100, that is, when the base 1100 is in the radially expanded state, the cutting assembly 1000 is also in the radially expanded state, and when the base 1100 is in the radially contracted state, the cutting assembly 1000 is also in the radially contracted state accordingly.

[0046] like Figure 2As shown, when the base 1100 is in the radial contraction state, the portion on which the cutting portion 1200 is arranged extends toward the axis of the base 1100, thereby forming a recess 1101 on the outer circumference of the base 1100 to accommodate the cutting portion 1200. In other words, when the base 1100 is in the radial contraction state, the cutting portion 1200 is located in the recess 1101 and does not protrude from the base 1100, thereby preventing the outer circumference of the base 1100 from protruding from the outer circumference, thereby ensuring the passability of the base 1100 in the blood vessel. In this way, on the one hand, the cutting assembly 1000 in the radial contraction state has a smaller outer diameter, and when the cutting assembly 1000 is applied to vascular lesions, it can adapt to small blood vessels of smaller size and easily pass through the narrow part and curved part of the blood vessel; on the other hand, it also avoids the situation that the cutting portion 1200 damages the blood vessel wall when the cutting assembly 1000 is transported. In addition, when the base 1100 switches from the radial contraction state to the radial expansion state, the distance that the recess 1101 expands outward is greater than the distance that the portion of the base 1100 other than the recess 1101 expands radially outward, so that the cutting portion 1200 is fully exposed and can effectively cut the calcified tissue and / or plaque tissue on the blood vessel.

[0047] In actual use, the medical cutting device 100 is used with Figure 7 The medical cutting device 100 is matched with the balloon catheter 200 shown, for example, the medical cutting device 100 is sleeved on a part of the outer circumference of the balloon catheter 200. The balloon catheter 200 includes a balloon body 4000. When the medical cutting device 100 is sleeved on a part of the outer circumference of the balloon catheter 200 so that the balloon body 4000 is inserted into the inner cavity of the base 1100, and when the balloon body 4000 is filled, the balloon body 4000 applies a radially outward force to the base 1100 so that the base 1100 expands radially. On the contrary, when the balloon body 4000 is depressurized, the radially outward force applied by the balloon body 4000 on the base 1100 gradually decreases to zero, and the base 1100 contracts radially toward the axial direction. Since the cutting portion 1200 is arranged on the outer surface of the base 1100, the base 1100 physically isolates the cutting portion 1200 from the balloon body 4000, so that the cutting portion 1200 does not directly contact the balloon body 4000, thereby avoiding the problem that the cutting portion 1200 damages the balloon body 4000 due to the reverse force generated when applying cutting force to the calcified tissue and / or plaque tissue, thereby causing the balloon body 4000 to release pressure, causing the base 1100 to shrink radially, resulting in the inability to continue cutting the calcified tissue and / or plaque tissue.

[0048] The embodiment of the present invention has no special restrictions on the shape of the recess 110, that is, the recess 1101 can have any suitable shape, such as a U-shape or a substantially U-shape. The radial dimension of the recess 1101 of the base 1100 is determined according to the radial dimension of the cutting portion 1200 of the base 1100, as long as the cutting portion 1200 can be completely accommodated in the recess 1101 without protruding from the base 1100.

[0049] When producing the cutting assembly 1000, the substrate 1100 is pre-shaped into the radial contraction state. It should be understood that the substrate 1100 should be made of a material with high elasticity, so that when the substrate 1100 is subjected to a radially outward force, the substrate 1100 expands radially and stores elastic potential energy. When the force is canceled, the substrate 1100 releases the elastic potential energy and switches to the radial contraction state under the action of the elastic potential energy. Optional materials include metal materials or polymer materials, and the optional metal material is, for example, nickel-titanium alloy.

[0050] Usually, if Figure 1 , Figure 3 and Figure 5 As shown, the base 1100 includes a first proximal connection portion 1110, a main body portion 1120 and a first distal connection portion 1130 which are connected in sequence. When the base 1100 is in the radial expansion state, the outer diameter of the first proximal connection portion 1110 gradually increases from the proximal end to the distal end, the main body portion 1120 has a substantially uniform outer diameter, and the outer diameter of the first distal connection portion 1130 gradually decreases from the proximal end to the distal end.

[0051] In some optional embodiments, please refer to Figure 1 , Figure 3 and Figure 5 The first proximal connecting portion 1110 includes a plurality of proximal connecting wires 1111 and a proximal engaging ring 1112, and the two ends of the proximal connecting wires 1111 are respectively connected to the proximal engaging ring 1112 and the main body 1120. When the base 1100 is in the radially expanded state, the outer diameter of the proximal engaging ring 1112 is smaller than the outer diameter of the main body 1120. All the proximal connecting wires 1111 are arranged at intervals along the circumference of the base 1100.

[0052] The first distal connection part 1130 includes a plurality of distal connection wires 1131 and a distal coupling ring 1132, and the two ends of the distal connection wires 1131 are respectively connected to the distal coupling ring 1132 and the main body 1120. When the base 1100 is in the radial expansion state, the outer diameter of the distal coupling ring 1132 is smaller than the outer diameter of the main body 1120. All the distal connection wires 1131 are arranged at intervals along the circumference of the base 1100.

[0053] The main body 1120 includes a plurality of main body engagement rings 1121 and a plurality of main body connection wires 1122. All the main body engagement rings 1121 are arranged at intervals along the axial direction of the base 1100, and the main body engagement ring 1121 at the most proximal end is connected to the first proximal end connection portion 1110, specifically connected to the distal ends of all the proximal end connection wires 1111; the main body engagement ring 1121 at the most distal end is connected to the first distal end connection portion 1130, specifically connected to the proximal ends of all the distal end connection wires 1131. All the main body connection wires 1122 are arranged at intervals along the circumferential direction of the base 1100.

[0054] Each of the main body engagement rings 1121 is connected to all of the main body connection wires 1122, and each of the main body connection wires 1122 is connected to all of the main body engagement rings 1121. Each of the cutting portions 1200 is disposed at the junction of one of the main body engagement rings 1121 and one of the main body connection wires 1122. The cutting portion 1200 is connected to the main body engagement rings 1121 and / or the main body connection wires 1122 by welding or any other suitable means.

[0055] Further, when the base 1100 is in the radial contraction state, at least one first wavy structure 1121a is formed on each of the main body engagement rings 1121, and the crests and troughs of the first wavy structures 1121a are alternately arranged in the circumferential direction of the base 1100. One of the crests and troughs of the first wavy structure 1121a faces the first proximal connection portion 1110, and the other faces the first distal connection portion 1130. The first wavy structure 1121a and the recess 1101 are also staggered in the circumferential direction of the base 1100. By providing the first wavy structure 1121a on the main body engagement ring 1121, an expansion margin is reserved, which is conducive to the base 1100 expanding radially to a larger outer diameter under the action of a radially outward force.

[0056] And, when the base 1100 is in the radial contraction state, at least one second wavy structure 1122a is formed on each of the main body connecting wires 1122. The crests and troughs of the second wavy structures 1122a are arranged alternately in the axial direction of the base 1100, and the crests and troughs of the second wavy structures 1122a are arranged relatively along the circumference of the base 1100 on the axial projection of the main body 1120 (i.e., the projection on a plane perpendicular to the axis of the base 1100). The second wavy structures 1122a are gradually straightened during the radial expansion process of the base 1100, so that the axial length of the main body 1120 can match the increase in the radial dimension and avoid the shortening of the main body 1100.

[0057] It should be understood that the first wavy structure 1121a and the second wavy structure 1122a always exist before the base 1100 is fully expanded. After the base 1100 is fully expanded, the main body joint ring 1121 is expanded into a circular or quasi-circular shape, so that the first wavy structure 1121a no longer exists, and the main body connecting wire 1122 is expanded into a straight line shape so that the second wavy structure 1122a no longer exists.

[0058] Similar to the main connecting wire 1122, when the base 1100 is in the radial contraction state, Figure 1 As shown, at least one third wavy structure 1111a may be formed on each of the proximal connecting wires 1111 , and / or at least one fourth wavy structure 1131a may be formed on each of the distal connecting wires 1131 .

[0059] The cutting part 1200 is, for example, a blade. The embodiment of the present invention has no particular limitation on the shape of the blade, as long as it can cut calcified tissue and / or plaque tissue in the blood vessel. Figure 6 The shape of the blade in the longitudinal section of the cutting assembly 1000 (ie, the section parallel to the axis of the base 1100) is any one of a trapezoidal, rectangular or sawtooth shape.

[0060] The cutting assembly 1000 includes a plurality of cutting parts 1200. In some embodiments, all the cutting parts are arranged at intervals in the circumferential direction of the base, and each cutting part extends continuously in the axial direction of the base (not shown in the figure).

[0061] In other embodiments, all the cutting portions 1200 are divided into a plurality of cutting portion groups (not marked in the figure), and each cutting portion group includes a plurality of the cutting portions 1200. The plurality of cutting portion groups are arranged at intervals along the circumference of the base 1100, and all the cutting portions 1200 in the same cutting portion group are arranged at intervals along the axial direction of the base 1100. In this embodiment, the cutting assembly 1200 is more likely to bend in the area between two axially adjacent cutting portions 1200. In other words, this arrangement of the cutting portions 1200 can reduce the rigidity of the cutting assembly 1000 and improve the bending performance of the cutting assembly 1000, so that the cutting assembly 1000 can more easily pass through the tortuous part of the blood vessel and accurately reach the lesion. In this embodiment, the number of the cutting portion groups is 2 to 5, each of the cutting portion groups includes 2 to 4 cutting portions 1200, and the length L of each cutting portion 1200 in the axial direction of the base 1100 (such as Figure 6 The diameter of the fiberglass shell (as shown) is 3mm to 6mm.

[0062] Optionally, refer to Figure 1 and Figure 3 The cutting assembly 1100 further includes a developing element, which is referred to as a first developing element 1300. The first developing element 1300 is disposed at any suitable position of the base 1100, and is used for developing under the action of X-rays when the cutting assembly 1000 is inserted into the body, so as to indicate the position of the cutting assembly 1000. In an optional implementation, there are multiple first developing elements 1300, and each of the first developing elements 1300 can be disposed between any two adjacent cutting portions 1200, for example, each of the first developing elements 1300 is disposed between two adjacent cutting portions 1200 along the axial direction of the base 1100; or, each of the first developing elements 1300 is disposed between two circumferentially adjacent cutting portions 1200.

[0063] In addition, please refer to Figure 1 and Figure 3 The medical cutting device 100 further includes a pushing rod 2000, the distal end of which is connected to the proximal end of the base 1100. The pushing rod 2000 is used to transmit a pushing force so that the cutting assembly 1000 in the radially compressed state can be pushed into the blood vessel.

[0064] Preferably, the push rod 2000 includes a rod body (not shown in the figure) and a hydrophilic coating (not shown in the figure) selectively disposed on the outer peripheral surface of the rod body. Here, the hydrophilic coating "selectively disposed on the outer peripheral surface of the rod body" means that the hydrophilic coating may be disposed on the outer peripheral surface of the rod body, or may not be disposed on the outer peripheral surface of the rod body. When the hydrophilic coating is disposed on the outer peripheral surface of the rod body, the hydrophilicity of the push rod 2000 can be improved and the pushing resistance can be reduced.

[0065] Furthermore, if Figures 7 to 11 As shown, the embodiment of the present invention further provides a medical cutting kit 10, the medical cutting kit 10 comprises a balloon catheter 200 and the aforementioned medical cutting device 100, the medical cutting device 100 is sleeved on a part of the outer circumference of the balloon catheter 200. The balloon catheter 200 comprises a tube assembly 3000 and a balloon body 4000 disposed at the distal end of the tube assembly 3000. The balloon body 4000 is used to be detachably inserted into the inner cavity of the base 1100.

[0066] The tube assembly 3000 and the balloon body 4000 of the balloon catheter 200 can be combined in any suitable manner in the prior art. For example, in an optional implementation, the tube assembly 3000 includes an inner tube 3100 and an outer tube 3200, the inner tube 3100 is partially inserted into the outer tube 3200, and the distal end of the inner tube 3100 extends from the distal end of the outer tube 3200, and the area between the outer surface of the inner tube 3100 and the inner surface of the outer tube 3200 constitutes a filling agent flow channel. The balloon body 4000 is sleeved on the outer peripheral surface of the distal end of the inner tube 3100, and the distal end of the balloon body 4000 is sealed and connected to the distal end of the inner tube 3100, the proximal end of the balloon body 4000 is connected to the proximal end of the outer tube 3200, and the filling cavity of the balloon body 4000 is connected to the filling agent flow channel.

[0067] Generally, the balloon body 4000 includes a second proximal connection portion 4100, a straight portion 4200 and a second distal connection portion 4300 connected in sequence from the proximal end to the distal end. The total length of the cutting portion 1200 in the axial direction of the medical cutting kit 10 is 2 / 3 to 3 / 4 of the axial length of the straight portion 4200.

[0068] It should be noted that, when the cutting portion 1200 extends continuously along the axial direction of the base 1100, the total length of the cutting portion 1200 in the axial direction of the medical cutting kit 10 refers to the length of a single cutting portion 1200 in the axial direction of the base 1100. When all the cutting portions 1200 are divided into a plurality of cutting portion groups, and all the cutting portions 1200 in each cutting portion group are arranged at intervals in the axial direction of the base 1100, the total length of the cutting portion 1200 in the axial direction of the medical cutting kit 10 refers to the sum of the lengths of all the cutting portions 1200 in the same cutting portion group in the axial direction of the base 1100.

[0069] In addition, the balloon catheter 200 includes a second developing element 5000 and a guide head 6000. The second developing element 5000 is disposed on the inner tube 3100 and is located inside the balloon body 4000, and is used to indicate the position of the balloon body 4000. The guide head 6000 is connected to the distal end of the inner tube 3100 and is located at the distal side of the balloon body 4000.

[0070] Next, the usage of the medical cutting kit 10 is introduced.

[0071] The first way to use:

[0072] First, the guide wire 300 is pre-buried.

[0073] Then, the cutting assembly 1000 of the medical cutting device 100 in the radially contracted state is sleeved on the guide wire 300. By applying a pushing force to the pushing rod 2000, the medical cutting device 100 is pushed along the guide wire 300, so that the cutting assembly 1000 moves from the proximal end to the distal end until the first distal end connecting portion 1130 of the base 1100 passes through the narrow part of the blood vessel and the main body 1120 is located at the location of the calcified tissue and / or plaque tissue. In this process, the position of the cutting assembly 1000 in the blood vessel is observed through the first developing element 1300.

[0074] Afterwards, the inner tube 3100 of the balloon catheter 200 in the gripping state is sleeved on the guide wire 300. By applying a pushing force to the tube assembly 3000, the balloon catheter 200 is pushed along the guide wire 300, so that the balloon body 4000 is inserted into the inner cavity of the base 1100, and the guide head 6000 is inserted out from the distal end of the base 1100. During this process, the position of the balloon body 4000 in the blood vessel is observed through the second developing element 5000. At this time, the relative position relationship between the medical cutting device 100 and the balloon assembly 200 is as shown in FIG. Figure 8 and Fig. 9 shown.

[0075] Subsequently, the filling agent is perfused into the filling cavity of the balloon body 4000 through the filling agent flow channel to fill the balloon body 4000. During the filling process, the balloon body 4000 applies a radially outward force to the base 1100 to push the base 1100 to expand radially and push the cutting portion 1200 out so that the cutting portion 1200 protrudes from the base 1100 and can cut the calcified tissue and / or plaque tissue. At this time, the relative position relationship between the medical cutting device 100 and the balloon assembly 200 is as shown in FIG. Fig.10 and Fig.11 shown.

[0076] After the cutting is completed, the filling agent is discharged from the filling cavity through the filling agent flow channel, so that the balloon body 4000 is depressurized. At the same time, the force exerted by the balloon body 4000 on the base body 1100 gradually decreases to zero. The base body 1100 returns to the radial contraction state under the action of its own elastic force.

[0077] Next, the balloon catheter 200 is first withdrawn from the body, then the medical cutting device 100, and finally the guide wire 300 is withdrawn from the body; or, the balloon catheter 200 and the medical cutting device 100 are withdrawn from the body at the same time, and then the guide wire 300 is withdrawn from the body.

[0078] The second way to use:

[0079] First, the medical cutting device 100 in the radially contracted state and the balloon catheter 200 in the crimped state are assembled in vitro. That is, the balloon body 4000 of the balloon catheter 200 in the crimped state is inserted into the inner cavity of the base 1100 in the radially contracted state in advance, and the guide head 6000 is extended from the distal end of the base 1100.

[0080] Then, the inner tube 3100 of the balloon catheter 200 is sleeved onto the pre-buried guide wire 300 .

[0081] Afterwards, a pushing force is applied to the tube assembly 3000 of the balloon catheter 200 and / or the pushing rod 2000 of the medical cutting device 100 to push the medical cutting kit 10, so that the cutting assembly 1000 and the balloon body 4000 enter the blood vessel and reach the lesion location.

[0082] The subsequent usage steps are the same as the first usage method mentioned above and will not be repeated here.

[0083] In summary, in the technical solution provided by the present invention, by forming a depression for accommodating the cutting part at the position where the cutting part is set in the base of the medical cutting device in the radial contraction state, so that the cutting part does not protrude from the base, the medical cutting device in the radial contraction state can have a smaller outer diameter, so that the medical cutting device can enter small blood vessels with smaller diameters, and then cut the calcified tissue and / or plaque tissue in the small blood vessels. Moreover, during the transportation and positioning process of the medical cutting device, the cutting part will not damage the blood vessel wall. In addition, when a radially outward force is applied to the base by the balloon body of the balloon catheter, since the base isolates the cutting part from the balloon body, the cutting part will not damage the balloon body.

[0084] Although the present invention is disclosed as above, it is not limited thereto. Those skilled in the art may make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include these modifications and variations.

Claims

1. A medical cutting device, characterized in that: It comprises a base body and a plurality of cutting parts; the base body has an inner cavity extending through the base body in the axial direction; the cutting parts are arranged on the outer peripheral surface of the base body; The base is configured to expand radially when subjected to a radially outward force, and to contract radially when the force is canceled; when the base is in a radially contracted state, a portion of its outer circumferential surface where the cutting portion is provided forms a recess for accommodating the cutting portion.

2. The medical cutting device according to claim 1, characterized in that: All the cutting portions are arranged at intervals along the circumferential direction of the base body, and each of the cutting portions extends continuously along the axial direction of the base body.

3. The medical cutting device according to claim 1, characterized in that: All the cutting parts are divided into a plurality of cutting part groups, each of which includes a plurality of cutting parts; all the cutting part groups are arranged at intervals along the circumference of the base, and all the cutting parts in the same cutting part group are arranged at intervals along the axial direction of the base.

4. The medical cutting device according to any one of claims 1 to 3, characterized in that: The recess is U-shaped in a cross section of the base body.

5. The medical cutting device according to any one of claims 1 to 3, characterized in that: The cutting device further comprises a developing element; each of the developing elements is arranged on the substrate and located between two adjacent cutting parts.

6. The medical cutting device according to claim 1, characterized in that: The base comprises a first proximal connecting portion, a main body portion and a first distal connecting portion which are connected in sequence; the cutting portion is arranged on the main body portion.

7. The medical cutting device according to claim 6, characterized in that: The main body portion includes a plurality of main body coupling rings and a plurality of main body connecting wires; all of the main body coupling rings are arranged at intervals along the axial direction of the base, and the main body coupling ring located at the nearest end is connected to the first proximal connecting portion, and the main body coupling ring located at the farthest end is connected to the first distal connecting portion; all of the main body connecting wires are arranged at intervals along the circumferential direction of the base; each of the main body coupling rings is connected to all of the main body connecting wires, and each of the main body connecting wires is connected to all of the main body coupling rings; each of the cutting portions is arranged at the junction of a main body coupling ring and a main body connecting wire.

8. The medical cutting device according to claim 7, characterized in that: When the base is in the radially contracted state, at least one first wavy structure is formed on the main body engaging ring, and the crests and troughs of the first wavy structure are alternately arranged along the circumference of the base, and one of the crests and troughs of the first wavy structure is toward the first proximal connecting portion, and the other is toward the first distal connecting portion; the first wavy structure and the recess are staggered in the circumference of the base.

9. The medical cutting device according to claim 7, characterized in that: When the base is in the radially contracted state, at least one second wavy structure is formed on the main connecting wire, and the crests and troughs of the second wavy structure are alternately arranged in the axial direction of the base; the crests and troughs of the second wavy structure are relatively arranged along the circumference of the base on the axial projection of the main body.

10. The medical cutting device according to claim 1, characterized in that: The medical cutting device further comprises a push rod, which comprises a rod body and a hydrophilic coating optionally disposed on the outer peripheral surface of the rod body, and the distal end of the push rod is connected to the proximal end of the substrate.

11. The medical cutting device according to claim 1, characterized in that: When the base changes from a contracted state to an expanded state, the radially outward expansion distance of the recess is greater than the radially outward expansion distance of other parts of the base.

12. A medical cutting kit, characterized in that: It comprises a balloon catheter and the medical cutting device as described in any one of claims 1 to 11, wherein the balloon catheter comprises a tube assembly and a balloon body arranged on the distal end of the tube assembly, and the medical cutting device is used to be sleeved on a part of the outer circumference of the balloon catheter, and the balloon body is detachably inserted into the inner cavity of the base.

13. The medical cutting kit according to claim 12, characterized in that: The balloon body comprises a second proximal connecting portion, a straight portion, and a second distal connecting portion connected in sequence; The total length of the cutting portion in the axial direction of the medical cutting kit is 2 / 3 to 3 / 4 of the axial length of the straight portion.

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