Rotary grinding structure and rotary grinding guide pipe system

Abstract

The invention relates to a rotary grinding structure and a rotary grinding catheter system, a flexible driving shaft is provided with an axial through guide channel, a first rotary grinding element is provided with a guide through hole with two through ends, the first rotary grinding element is arranged at the far end of the flexible driving shaft, the guide through hole is communicated with the guide channel, and a second rotary grinding element is provided with an eccentric shaft hole with two through ends. The second rotary grinding element is eccentrically arranged on the flexible driving shaft in a sleeving mode through the eccentric shaft hole, and the rotary grinding outer sheath tube is arranged outside the flexible driving shaft in a sleeving mode. The diameter of the outer contour of the first rotary grinding element is small, radial opening of the complete occlusion lesion is facilitated, the second rotary grinding element is assembled in an eccentric mode, the rotary grinding diameter can continue to be enlarged after the first rotary grinding element is opened in the radial direction, and through sequential rotary grinding matching of the first rotary grinding element and the second rotary grinding element, the rotary grinding efficiency is improved. The rotary grinding structure has two opening functions of concentric opening and eccentric lumen gain in the rotary grinding opening process, and opening of chronic CTO lesion and lumen expansion of narrow lesion can be effectively achieved.

Description

Technical Field

[0001] The present application relates to the technical field of medical devices, and in particular to a rotational atherectomy structure and a rotational atherectomy catheter system. Background Art

[0002] Atherosclerosis is common in the arteries of the lower limbs, characterized by the formation of fibrolipid plaques and calcified lesions in the intima and media of the arteries, resulting in thickening of the vessel wall and stenosis of the lumen. It is mainly distributed in the intima and media of the femoral popliteal and infrapopliteal arteries. Due to the stenosis or even complete occlusion of the arterial lumen of the lesions, symptoms such as lower limb ischemia and gangrene are caused. If not treated in time, it often leads to claudication or even amputation. Atherosclerotic plaques may present different characteristics depending on the texture of the plaques and calcifications. In medical practice, a atherectomy catheter system is usually used for pretreatment of severe calcified lesions. The principle is to use a grinding head to rotate at high speed at the vascular lesions to remove calcified or fibrotic lipid plaques, open the occluded blood vessels, obtain a smoother vascular lumen gain, and facilitate the subsequent placement of drug balloons and stents. When performing interventional treatment for stenotic lesions at the opening and bifurcation of the vascular intima, as well as angled, eccentric, long-segment, and point-shaped stenotic lesions, orbital atherectomy of peripheral arterial plaques has become a clinically used method for removing atherosclerotic plaques.

[0003] The atherectomy catheter system usually includes a control host, a drive handle, a flexible drive shaft and a grinding head. The control host drives the flexible drive shaft to rotate at high speed, and the grinding head at the distal end of the flexible drive shaft is pushed forward to contact and grind away the lesions, ablating the plaque or calcified lesions into tiny particles smaller than the diameter of red blood cells. The use of peripheral artery orbital atherectomy for treatment can be applicable to severely calcified lesions. The lesions are first pretreated with orbital atherectomy to prepare the lumen, and then a drug balloon or stent is inserted to improve the success rate of interventional treatment and reduce the occurrence of complications. In the atherectomy catheter system, the grinding heads inserted into the body vary in shape, but they all have certain limitations, namely, they cannot pass through narrower lesions, such as narrow lesions smaller than the diameter of the flexible drive shaft or even chronic occlusive lesions.

[0004] In addition, the outer sleeve of the existing atherectomy catheter system is a simple polymer tube, and the head end has no special design. The flexibility, wear resistance and visualization of the head end are all poor. The poor flexibility of the head end will make the catheter not smooth during the pushing and retracting process, and it is easy to damage the blood vessels when turning; the head end has poor wear resistance, and the inner cavity is easily worn by high-speed moving parts; the visualization of the head end is not good, and the surgeon cannot use angiography to identify the position of the grinding head relative to the outer sleeve during the operation, and cannot intuitively display the pushing stroke of the grinding head. Summary of the invention

[0005] Based on this, it is necessary to provide a rotational atherectomy structure and a rotational atherectomy catheter system to address the above-mentioned technical problems.

[0006] The present application provides a rotational atherectomy structure, the rotational atherectomy structure comprising:

[0007] A flexible drive shaft, wherein the flexible drive shaft has an axially penetrating guide channel;

[0008] A first atherectomy element, wherein the first atherectomy element has a guide through hole with two ends extending therethrough, the first atherectomy element is coaxially disposed at the distal end of the flexible drive shaft, and the guide through hole is communicated with the guide channel;

[0009] a second atherectomy element, wherein the second atherectomy element has an eccentric shaft hole extending through both ends, and the second atherectomy element is eccentrically sleeved on the flexible driving shaft through the eccentric shaft hole;

[0010] The atherectomy outer sheath is sleeved on the outside of the flexible drive shaft, and the atherectomy outer sheath comprises a first sheath segment and a second sheath segment, wherein the first sheath segment is located at the distal end of the second sheath segment, and the flexibility of the first sheath segment is better than that of the second sheath segment.

[0011] In one embodiment, at least one of a toughening component, a wear-resistant component and a developing component is added to the polymer material of the first sheath segment, and at least one of flexibility, wear resistance and developing property of the first sheath segment is better than that of the second sheath segment.

[0012] In one embodiment, the outer contour of the first atherectomy element is a cylindrical structure or a truncated cone structure, and the first atherectomy element is coaxially assembled with the flexible driving shaft.

[0013] In one embodiment, the first atherectomy element is a cylindrical atherectomy element, and the cylindrical atherectomy element is coaxially connected to the flexible drive shaft; or

[0014] The first atherectomy element is a truncated cone atherectomy element, which is coaxially connected to the flexible drive shaft, and the diameter of the truncated cone atherectomy element gradually decreases from the proximal direction to the distal direction of the flexible drive shaft; or,

[0015] The first atherectomy element is a sleeve atherectomy end cap, and the sleeve atherectomy end cap is coaxially sleeved on the distal end of the flexible drive shaft; or,

[0016] The first athermal element comprises a laying base layer and a athermal coating layer. The laying base layer is laid on the outer wall of the flexible driving shaft, and the athermal coating layer is arranged on the outer layer of the laying base layer.

[0017] In one embodiment, the outer surface of the second rotational atherectomy element has a rotational atherectomy region, and the rotational atherectomy region includes at least two rotational atherectomy unit surfaces, and different rotational atherectomy unit surfaces are in different planes.

[0018] In one embodiment, the atherectomy region of the second atherectomy element comprises a first atherectomy unit surface, a second atherectomy unit surface and a third atherectomy unit surface which are axially connected, the second atherectomy unit surface is located between the first atherectomy unit surface and the third atherectomy unit surface, the first atherectomy unit surface is a chamfered atherectomy surface inclined toward the distal direction, the second atherectomy unit surface is a cylindrical atherectomy surface, and the third atherectomy unit surface is a chamfered atherectomy surface inclined toward the proximal direction.

[0019] In one embodiment, the flexible driving shaft is formed by winding a plurality of the braided spiral wires.

[0020] In one embodiment, the proximal end of the first sheath segment is fused to the distal end of the second sheath segment, so that the inner cavity of the first sheath segment is connected to the inner cavity of the second sheath segment.

[0021] In one embodiment, the first sheath segment includes a connected diameter segment and a variable diameter segment, the proximal end of the variable diameter segment is connected to the distal end of the diameter segment, and the diameter of the variable diameter segment gradually decreases from the proximal direction to the distal direction of the first sheath segment.

[0022] In one embodiment, the outer sheath of the rotary grinding tube comprises an inner tube layer, a middle tube layer and an outer tube layer which are sequentially arranged from the inner layer to the outer layer. The inner tube layer is made of a low-friction polymer material, the middle tube layer is made of a metal material, and the outer tube layer is made of a high-toughness polymer material.

[0023] The present application provides a rotational atherectomy catheter system, the rotational atherectomy catheter system comprising:

[0024] The rotational atherectomy structure;

[0025] A control host is drivingly connected to the atherectomy structure.

[0026] In the above-mentioned atherectomy structure and atherectomy catheter system, the outer diameter of the first atherectomy element is not much different from that of the flexible drive shaft, and the outer diameter of the first atherectomy element is smaller than that of the second atherectomy element, so that it is convenient to radially open the completely occluded lesion, and the second atherectomy element adopts an eccentric assembly method, specifically, the second atherectomy element is eccentrically assembled on the flexible drive shaft, so that the second atherectomy element has an eccentrically protruding atherectomy area, which is convenient for continuing to expand the atherectomy diameter after the first atherectomy element is radially opened. Therefore, through the first atherectomy element and the second atherectomy element, the atherectomy structure has two opening functions of concentric opening and eccentric lumen gain during the atherectomy opening process, which can effectively realize the opening of chronic occlusive lesions and the expansion of the lumen of stenotic lesions. At the same time, the atherectomy outer sheath tube not only ensures torsional rigidity, but also improves the flexibility of passing through the blood vessel and the tracking performance during the operation through the different performance designs of the first sheath tube segment and the second sheath tube segment. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 A schematic structural diagram of a rotational grinding structure provided in one embodiment of the present application.

[0028] Figure 2 A cross-sectional view of a first rotational atherectomy element according to one embodiment of the present application.

[0029] Figure 3 A cross-sectional view of a second rotational atherectomy element according to one embodiment of the present application.

[0030] Figure 4 A schematic structural diagram of a rotational grinding structure provided in another embodiment of the present application.

[0031] Figure 5 A cross-sectional view of a first rotational atherectomy element is provided according to another embodiment of the present application.

[0032] Figure 6 A cross-sectional view of a rotational atherectomy structure provided in yet another embodiment of the present application.

[0033] Figure 7 An axial cross-sectional view of a rotational atherectomy outer sheath provided in one embodiment of the present application.

[0034] Figure 8 A radial cross-sectional view of a rotational atherectomy outer sheath provided in one embodiment of the present application.

[0035] Figure Number:

[0036] 1000, flexible driving shaft; 2000, first atherectomy element; 3000, second atherectomy element; 4000, atherectomy outer sheath;

[0037] 1000a, guide channel; 1100, braided spiral wire;

[0038] 2000a, guide through hole; 2100, lay base layer; 2200, spin-milling plating;

[0039] 3000a, eccentric shaft hole; 3100, atherectomy area; 3100a, first atherectomy unit surface; 3100b, second atherectomy unit surface; 3100c, third atherectomy unit surface;

[0040] 4100, first sheath tube segment; 4200, second sheath tube segment; 4100a, diameter-changing segment; 4100b, diameter segment; 4000a, inner tube layer; 4000b, middle tube layer; 4000c, outer tube layer. DETAILED DESCRIPTION

[0041] In order to make the above-mentioned purposes, features and advantages of the present application more obvious and easy to understand, the specific implementation methods of the present application are described in detail below in conjunction with the accompanying drawings. In the following description, many specific details are set forth to facilitate a full understanding of the present application. However, the present application can be implemented in many other ways different from those described herein, and those skilled in the art can make similar improvements without violating the connotation of the present application, so the present application is not limited by the specific embodiments disclosed below.

[0042] In the description of the present application, it should be understood that if the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc. appear, the orientation or position relationship indicated by these terms is based on the orientation or position relationship shown in the accompanying drawings, which is only for the convenience of describing the present application and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present application.

[0043] In addition, if the terms "first" or "second" appear, these terms are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include at least one of the features. In the description of this application, if the term "plurality" appears, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0044] In this application, unless otherwise clearly specified and limited, if the terms "installed", "connected", "connected", "fixed" and the like appear, these terms should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integrated connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to the specific circumstances.

[0045] In the present application, unless otherwise clearly specified and limited, if there is a description that a first feature is "above" or "below" a second feature, etc., or similar descriptions appear, it may mean that the first and second features are in direct contact, or that the first and second features are in indirect contact through an intermediate medium. Moreover, the first feature being "above", "above" and "above" the second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. The first feature being "below", "below" and "below" the second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

[0046] It should be noted that if an element is referred to as being "fixed to" or "disposed on" another element, it may be directly on the other element or there may be a central element. If an element is considered to be "connected to" another element, it may be directly connected to the other element or there may be a central element at the same time. If any, the terms "vertical", "horizontal", "upper", "lower", "left", "right" and similar expressions used in this application are for illustrative purposes only and do not represent the only implementation method.

[0047] In order to more clearly describe the structure of the atherectomy structure and the structure of the atherectomy catheter system, the term "distal end" is defined herein to mean the end away from the operator during the surgical operation, i.e. Figure 1 The left side of the figure shows that the "proximal end" refers to the end closer to the operator during the surgical operation, i.e. Figure 1 Unless otherwise defined, all technical and scientific terms used in this application have the same meaning as those commonly understood by technicians in the technical field of this application. The terms used in this application in the specification are only for the purpose of describing specific embodiments and are not intended to limit this application.

[0048] See also Figures 1 to 3 As shown, an embodiment of the present application provides a rotational atherectomy structure, which includes a flexible drive shaft 1000, a first rotational atherectomy element 2000 and a second rotational atherectomy element 3000, and refer to Figure 6As shown, the flexible drive shaft 1000 has an axially penetrating guide channel 1000a, the first atherectomy element 2000 has a guide through hole 2000a penetrating at both ends, the first atherectomy element 2000 is coaxially arranged at the distal end of the flexible drive shaft 1000, the guide through hole 2000a is connected to the guide channel 1000a, the second atherectomy element 3000 has an eccentric shaft hole 3000a penetrating at both ends, and the second atherectomy element 3000 is eccentrically sleeved on the flexible drive shaft 1000 through the eccentric shaft hole 3000a. The rotation of the flexible drive shaft 1000 can drive the first atherectomy element 2000 and the second atherectomy element 3000 to rotate synchronously. The first atherectomy element 2000 is located at the distal end of the flexible drive shaft 1000, see Figure 1 As shown, the outer contour diameters of the first rotational atherectomy element 2000 and the flexible drive shaft 1000 are not much different. Compared with the second rotational atherectomy element 3000, the outer contour diameter of the first rotational atherectomy element 2000 is smaller, which is convenient for radial opening of completely occluded lesions, while the second rotational atherectomy element 3000 adopts an eccentric assembly method, specifically, the second rotational atherectomy element 3000 is eccentrically assembled on the flexible drive shaft 1000.

[0049] Therefore, since the first atherectomy element 2000 and the second atherectomy element 3000 are respectively coaxially assembled and eccentrically assembled relative to the flexible drive shaft 1000, and their outer diameters are also different, they can be used to achieve different atherectomy functions during the atherectomy process. Figure 1 As shown, the eccentric assembly of the second atherectomy element 3000 on the flexible driving shaft 1000 can provide the second atherectomy element 3000 with an eccentrically protruding atherectomy area 3100, which is convenient for continuing to expand the atherectomy diameter after the radial opening of the first atherectomy element 2000. Therefore, through the sequential atherectomy of the first atherectomy element 2000 and the second atherectomy element 3000, the atherectomy structure has two opening functions of concentric opening and eccentric lumen gain during the atherectomy opening process, which can effectively achieve the opening of chronic occlusive lesions and the lumen expansion of stenotic lesions.

[0050] The first atherectomy element 2000 can adopt a variety of structures and shapes, as long as the first atherectomy element 2000 can be stably disposed at the distal end of the flexible drive shaft 1000, and the outer contour diameters of the first atherectomy element 2000 and the flexible drive shaft 1000 are not much different, and can be used for radial opening of completely occluded lesions during atherectomy. For example, in one embodiment, the outer contour of the first atherectomy element 2000 adopts a cylindrical structure or a truncated cone structure, and the first atherectomy element 2000 is coaxially assembled with the flexible drive shaft 1000.

[0051] In one embodiment, the first atherectomy element 2000 is a cylindrical atherectomy element (not shown), which is coaxially connected to the flexible drive shaft 1000, and the connection between the two is end-to-end. Figure 1 As shown, the first atherectomy element 2000 is a truncated cone atherectomy element, which is coaxially connected to the flexible drive shaft 1000, and the diameter of the truncated cone atherectomy element gradually decreases from the proximal direction to the distal direction of the flexible drive shaft 1000. The truncated cone design of the truncated cone atherectomy element can facilitate the passage of the lesion, and the guide through hole 2000a inside the truncated cone atherectomy element can be designed with equal diameter or non-equal diameter, wherein the equal diameter design means that the guide through hole 2000a always maintains a fixed through hole diameter size along the axial through direction, and correspondingly, the non-equal diameter design means that the guide through hole 2000a does not always maintain a fixed through hole diameter size along the axial through direction, but the through hole diameter can change in the axial direction, and the change can be a regular change or an irregular change, such as a gradual increase or a gradual decrease.

[0052] For example, when the equal diameter design is used, the diameter of the guide hole 2000a can be selected between 0.2 mm and 0.9 mm, which can allow the atherectomy guide wire of 0.009 in to 0.035 in to pass through. At this time, the atherectomy guide wire can pass through the guide channel 1000a of the flexible drive shaft 1000 and the guide hole 2000a of the ferrule-shaped atherectomy element in sequence. The ferrule-shaped outer contour of the ferrule-shaped atherectomy element can be selected as a curved arc, and the outer contour surface of the ferrule-shaped atherectomy element can be designed to be smooth, or diamond particles can be plated on the outer contour surface of the ferrule-shaped atherectomy element, and the size of the diamond particles can be selected to be 10 μm to 70 μm, which is used for the opening of severe stenosis lesions.

[0053] See also Figure 4 and Figure 5 As shown, the first atherectomy element 2000 is a set atherectomy end cap, which can be coaxially mounted on the distal end of the flexible drive shaft 1000 in a set manner, rather than being connected end to end. The atherectomy end cap can be a cylindrical end cap structure, and a guide hole 2000a is provided on the distal end face of the atherectomy end cap. The diameter of the guide hole 2000a can be selected to be 0.2mm to 0.9mm, which can allow atherectomy guide wires of 0.009in to 0.035in to pass through. The outer contour surface of the atherectomy end cap can be designed to be smooth, or the outer contour surface of the atherectomy end cap can be plated with diamond particles, and the size of the diamond particles can be selected to be 10μm to 70μm, which can be used for the opening of severe stenosis lesions.

[0054] See also Figure 6As shown, the first atherectomy element 2000 comprises a laying base 2100 and an atherectomy coating 2200, wherein the laying base 2100 is laid on the outer wall of the flexible drive shaft 1000, and the atherectomy coating 2200 is arranged on the outer layer of the laying base 2100. This first atherectomy element 2000 has no fixed substrate, but only a base laid on the surface of the flexible drive shaft 1000. When constructing this first atherectomy element 2000, the laying base 2100 is coated with tin material or the like in the surface and concave gap of the flexible drive shaft 1000, so that the corresponding area on the surface of the flexible drive shaft 1000 becomes a flat cylindrical structure, and then a diamond electroplating process is adopted to cover the surface of the flexible drive shaft 1000 with a dense diamond grinding layer, i.e., the atherectomy coating 2200, and the diamond particle size can be selected to be 10 μm to 70 μm, which can be used for the opening of severe stenosis lesions.

[0055] An eccentric shaft hole 3000a adapted to the second grinding element 3000 can be constructed inside according to the shaft structure and shape of the flexible driving shaft 1000. For example, the eccentric shaft hole 3000a is an equal-diameter eccentric shaft hole or a non-equal-diameter eccentric shaft hole, wherein the equal-diameter eccentric shaft hole refers to the eccentric shaft hole 3000a always maintaining a fixed through-hole diameter size along the axial through-direction, and correspondingly, the non-equal-diameter eccentric shaft hole refers to the eccentric shaft hole 3000a not always maintaining a fixed through-hole diameter size along the axial through-direction, but the through-hole diameter can change in the axial direction, and the change can be a regular change or an irregular change, such as a gradual increase or decrease. The constructed eccentric shaft hole 3000a can pass through the flexible driving shaft 1000, and the flexible driving shaft 1000 can be fixed to the second atherectomy element 3000 by welding, bonding, etc. The outer diameter of the flexible driving shaft 1000 can be set to 0.6mm to 1mm, and the center line of the second atherectomy element 3000 is not coaxial with the center line of the flexible driving shaft 1000, so that the sleeve assembly of the second atherectomy element 3000 and the flexible driving shaft 1000 has a certain eccentricity, and the eccentricity can be designed to be 0.1mm to 0.5mm.

[0056] The second atherectomy element 3000 can adopt a variety of structures and shapes, as long as it is ensured that the second atherectomy element 3000 can be stably mounted on the outside of the flexible drive shaft 1000, and the second atherectomy element 3000 can form an outer contour diameter larger than that of the first atherectomy element 2000, and can continue to expand the atherectomy diameter after the atherectomy of the first atherectomy element 2000 is completed. For example, in one embodiment, the outer surface of the second atherectomy element 3000 has an atherectomy area 3100, and the atherectomy area 3100 includes at least two atherectomy unit surfaces, and different atherectomy unit surfaces are in different planes, so that plane angles are formed between different atherectomy unit surfaces, thereby constructing an uneven atherectomy area 3100 suitable for atherectomy.

[0057] The number of atherectomy unit surfaces and the plane angles can be designed according to actual needs. For example, in one embodiment, the atherectomy region 3100 of the second atherectomy element 3000 includes a first atherectomy unit surface 3100a, a second atherectomy unit surface 3100b and a third atherectomy unit surface 3100c which are axially connected, the second atherectomy unit surface 3100b is located between the first atherectomy unit surface 3100a and the third atherectomy unit surface 3100c, the first atherectomy unit surface 3100a is a chamfered atherectomy surface inclined toward the distal direction, the second atherectomy unit surface 3100b is a cylindrical atherectomy surface, and the third atherectomy unit surface 3100c is a chamfered atherectomy surface inclined toward the proximal direction. The second atherectomy unit surface 3100b located in the middle is mainly used for performing atherectomy, while the first atherectomy unit surface 3100a facing the distal direction and the second atherectomy unit surface 3100b facing the proximal direction can facilitate bidirectional atherectomy during atherectomy. When a stenotic lesion is stuck, the atherectomy lesion can still be advanced and retracted, which not only increases the atherectomy efficiency but also reduces the surgical risk.

[0058] The first atherectomy unit surface 3100a and the third atherectomy unit surface 3100c may have the same or different inclination angles relative to the flexible drive shaft 1000. For example, see Figure 3 As shown, the inclination angle of the first atherectomy unit surface 3100a relative to the flexible driving shaft 1000 is a, and the inclination angle of the third atherectomy unit surface 3100c relative to the flexible driving shaft 1000 is b. The inclination angle a of the first atherectomy unit surface 3100a may be less than or equal to the inclination angle b of the third atherectomy unit surface 3100c.

[0059] The inclination angle of the first atherectomy unit surface 3100a relative to the flexible drive shaft 1000 can be set between 30° and 60°, and the inclination angle of the second atherectomy unit surface 3100b relative to the flexible drive shaft 1000 can be set between 30° and 60°. Those skilled in the art can construct the inclination angles of the first atherectomy unit surface 3100a and the second atherectomy unit surface 3100b relative to the flexible drive shaft 1000 according to actual use requirements, so that the first atherectomy unit surface 3100a and the second atherectomy unit surface 3100b can facilitate advancement and withdrawal during atherectomy in the distal direction and the proximal direction. The atherectomy region 3100 of the second atherectomy element 3000 is plated with diamond particles, and the size of the diamond particles can be selected to be 10μm to 70μm. The eccentric design of the second atherectomy element 3000 can generate centrifugal force during atherectomy, so that the second atherectomy element 3000 can cooperate with the first atherectomy element 2000 to achieve the opening gain of the vascular lumen.

[0060] The base material of the first atherectomy element 2000 and the second atherectomy element 3000 can be selected as stainless steel or tungsten alloy, etc. The assembly of the second atherectomy element 3000 can be adaptively adjusted according to the specific conditions of different materials and different eccentricities to achieve different lumen diameter gains. For example, according to the formula Fc=mv2 / r, if the second atherectomy element 3000 is selected from different materials and designed with different eccentricities, the centrifugal force generated during the atherectomy process can be changed, thereby achieving different lumen diameter gains.

[0061] The flexible drive shaft 1000 can be constructed in a variety of ways, so that the flexible drive shaft 1000 has a certain support performance, but also has a certain flexibility. The support performance helps the flexible drive shaft 1000 to advance in the blood vessel, and the flexibility enables the flexible drive shaft 1000 to have a deformation effect during the advancement process to prevent damage to the blood vessel wall. In one embodiment, the flexible drive shaft 1000 may include a plurality of braided winding wires 1100, and the flexible drive shaft 1000 is wound by the plurality of braided winding wires 1100. The flexible drive shaft 1000 is densely wound with multiple braided spiral wires 1100. The number of the braided spiral wires 1100 can be selected to be 1 to 9, the diameter of the braided spiral wires 1100 can be selected to be 0.1 mm to 0.2 mm, and the material of the braided spiral wires 1100 is a metal material, for example, stainless steel or nickel-titanium wire can be selected, so that the flexible drive shaft 1000 has sufficient supporting performance in the blood vessel lumen, that is, the ability of the material or structure to resist elastic deformation when subjected to force, so as to stably transmit torque to the first rotary grinding element 2000 and the second rotary grinding element 3000. At the same time, the flexible drive shaft 1000 will also have a certain flexibility so as to pass through the curved blood vessels smoothly.

[0062] Continue reading Figure 1 As shown in one embodiment, the atherectomy structure includes an atherectomy outer sheath 4000, which is sleeved on the outside of the flexible driving shaft 1000. Figure 7As shown, the atherectomy outer sheath 4000 includes a first sheath segment 4100 and a second sheath segment 4200, the first sheath segment 4100 is located at the distal end of the second sheath segment 4200, the proximal end of the first sheath segment 4100 is connected to the distal end of the second sheath segment 4200, specifically by welding, so that the inner cavity of the first sheath segment 4100 and the inner cavity of the second sheath segment 4200 are connected, and at least one of the flexibility, wear resistance and developability of the first sheath segment 4100 is better than that of the second sheath segment 4200. The first sheath segment 4100 has better flexibility and can pass through the lesion more easily. The first sheath segment 4100 has better wear resistance and can better protect the first sheath segment 4100 under high-speed rotation conditions. The first sheath segment 4100 has better visualization, which can enable the operator to identify the position of the first atherectomy element 2000 and the second atherectomy element 3000 relative to the atherectomy outer sheath 4000 during the operation, and intuitively display the pushing stroke of the first atherectomy element 2000 and the second atherectomy element 3000, thereby improving the convenience and safety of the operation. The atherectomy outer sheath 4000 ensures torsional rigidity and improves flexibility through blood vessels and tracking performance during the operation through the different performance designs of the first sheath segment 4100 and the second sheath segment 4200.

[0063] The first sheath segment 4100 and the second sheath segment 4200 can be made of polymer materials, and the polymer materials can be selected from polyether block polyamide (Pebax), polytetrafluoroethylene (PTFE), polyimide (PI), polyetheretherketone (PEEK) or polyamide (PA), etc., which are not limited here. The flexibility, wear resistance and developing properties of the first sheath segment 4100 can be achieved in a variety of ways. For example, although the first sheath segment 4100 and the second sheath segment 4200 are both made of polymer materials, toughening components, wear-resistant components and developing components can be added to the polymer material of the first sheath segment 4100, and the polymer material of the first sheath segment 4100 can be changed into a modified material, so that the first sheath segment 4100 has better flexibility, wear resistance and developing properties accordingly.

[0064] In a specific embodiment, the toughening component can be selected to add a toughening agent, such as silicon dioxide, to improve the ductility of the material and make it easier to pass through the lesion. The wear-resistant component can be selected to add polytetrafluoroethylene, polyethylene, nylon, etc. to improve wear resistance. The developing component can be selected to add a radiopaque filler, such as barium sulfate, bismuth oxychloride, bismuth trioxide, etc., so that the operator can use angiography to identify the position of the first atherectomy element 2000 and the second atherectomy element 3000 relative to the atherectomy outer sheath 4000 during the operation, and intuitively display the pushing stroke of the first atherectomy element 2000 and the second atherectomy element 3000, thereby improving the convenience and safety of the operation.

[0065] In one embodiment, the first sheath section 4100 includes a connected diameter section 4100b and a reduced diameter section 4100a, the proximal end of the reduced diameter section 4100a is connected to the distal end of the diameter section 4100b, and the diameter of the reduced diameter section 4100a gradually decreases from the proximal direction to the distal direction of the first sheath section 4100. The atherectomy outer sheath 4000 can be selected as a thin-walled tube, the interior of the atherectomy outer sheath 4000 is hollow, and the reduced diameter section 4100a of the first sheath section 4100 facilitates the atherectomy outer sheath 4000 to be pushed, and it will be smoother when passing through a curved blood vessel, and will not scratch the blood vessel wall, and will not cause blood vessel damage.

[0066] In one embodiment, the outer sheath tube 4000 of the atherectomy includes an inner tube layer 4000a, a middle tube layer 4000b and an outer tube layer 4000c, which are sequentially set from the inner layer to the outer layer. The inner tube layer 4000a is made of a low-friction polymer material, the middle tube layer 4000b is made of a metal material, and the outer tube layer 4000c is made of a high-toughness polymer material. Among them, the inner tube layer 4000a can be selected as a polytetrafluoroethylene (PTFE) polymer material, which has a low friction coefficient and can effectively reduce the relative friction with the flexible drive shaft 1000, the middle tube layer 4000b can be selected as a stainless steel braided layer, which can improve the rigidity and torsion resistance, and the outer tube layer 4000c can be selected as a polyether block polyamide (Pebax) polymer material, which has good toughness and is easy to pass through the lesion area.

[0067] The present application provides a rotational atherectomy catheter system, which includes a rotational atherectomy structure, a driving handle, and a control host. The control host is connected to the rotational atherectomy structure and can be used to control the high-speed rotation of a flexible driving shaft 1000 of the rotational atherectomy structure. At the same time, the operator can drive the high-speed rotating rotational atherectomy structure to move through the driving handle, so that the flexible driving shaft 1000 of the rotational atherectomy structure can gradually approach and reach the lesion location, and then at the lesion location, the first rotational atherectomy element 2000 and the second rotational atherectomy element 3000 on the flexible driving shaft 1000 cooperate to advance forward, contact and grind to remove the lesion, and ablate the plaque or calcified lesion into fine particles smaller than the diameter of red blood cells.

[0068] Before the atherectomy, physiological saline needs to be supplied through the infusion tube, and the peristaltic pump is turned on to empty the guide channel 1000a of the flexible drive shaft 1000. The distal end of the atherectomy guide wire first passes through the target blood vessel through the puncture sheath, and the puncture position of the atherectomy guide wire is fixed by hand. The proximal end of the atherectomy guide wire is inserted into the head end of the atherectomy prototype, and the drive handle is lifted. The first atherectomy element 2000 is gently pushed to 1 cm away from the proximal end of the target blood vessel, and the push is stopped. Operate the first atherectomy element 2000 to atherectomize the target blood vessel back and forth at a uniform speed (5mm / s). The single atherectomy time does not exceed 30s, and rest for 30s between each atherectomy. Repeat until the total atherectomy time reaches 4min, and then stop atherectomy. Those skilled in the art can use the atherectomy catheter system to implement atherectomy according to actual needs, and are not limited to the specific methods provided above.

[0069] The technical features of the above embodiments may be combined arbitrarily. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0070] The above embodiments only express several implementation methods of the present application, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the patent application. It should be pointed out that, for a person of ordinary skill in the art, several variations and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application. Therefore, the protection scope of the patent application shall be subject to the attached claims.

Claims

1. A rotational atherectomy structure, characterized in that: The atherectomy structure comprises: A flexible drive shaft, wherein the flexible drive shaft has an axially penetrating guide channel; A first atherectomy element, wherein the first atherectomy element has a guide through hole with two ends extending therethrough, the first atherectomy element is coaxially disposed at the distal end of the flexible drive shaft, and the guide through hole is communicated with the guide channel; a second atherectomy element, wherein the second atherectomy element has an eccentric shaft hole extending through both ends, and the second atherectomy element is eccentrically sleeved on the flexible driving shaft through the eccentric shaft hole; The atherectomy outer sheath is sleeved on the outside of the flexible drive shaft, and the atherectomy outer sheath comprises a first sheath segment and a second sheath segment, wherein the first sheath segment is located at the distal end of the second sheath segment, and the flexibility of the first sheath segment is better than that of the second sheath segment.

2. The rotational atherectomy structure according to claim 1, characterized in that: At least one of a toughening component, a wear-resistant component and a developing component is added to the first sheath tube segment, and at least one of flexibility, wear resistance and developing property of the first sheath tube segment is better than that of the second sheath tube segment.

3. The rotational atherectomy structure according to claim 1, characterized in that: The first atherectomy element is a cylindrical atherectomy element, and the cylindrical atherectomy element is coaxially connected to the flexible driving shaft; or, The first atherectomy element is a truncated cone atherectomy element, which is coaxially connected to the flexible drive shaft, and the diameter of the truncated cone atherectomy element gradually decreases from the proximal direction to the distal direction of the flexible drive shaft; or, The first atherectomy element is a sleeve atherectomy end cap, and the sleeve atherectomy end cap is coaxially sleeved on the distal end of the flexible drive shaft; or, The first athermal element comprises a laying base layer and a athermal coating layer. The laying base layer is laid on the outer wall of the flexible driving shaft, and the athermal coating layer is arranged on the outer layer of the laying base layer.

4. The rotational atherectomy structure according to claim 1, characterized in that: The outer surface of the second atherectomy element has an atherectomy region, and the atherectomy region includes at least two atherectomy unit surfaces, and different atherectomy unit surfaces are in different planes.

5. The rotational atherectomy structure according to claim 4, characterized in that: The atherectomy region of the second atherectomy element comprises a first atherectomy unit surface, a second atherectomy unit surface and a third atherectomy unit surface which are axially connected, the second atherectomy unit surface is located between the first atherectomy unit surface and the third atherectomy unit surface, the first atherectomy unit surface is a chamfered atherectomy surface inclined toward the distal direction, the second atherectomy unit surface is a cylindrical atherectomy surface, and the third atherectomy unit surface is a chamfered atherectomy surface inclined toward the proximal direction.

6. The rotational atherectomy structure according to claim 1, characterized in that: The flexible driving shaft is formed by winding a plurality of braided spiral wires.

7. The rotational atherectomy structure according to claim 1, characterized in that: The proximal end of the first sheath tube segment is fused with the distal end of the second sheath tube segment, so that the inner cavity of the first sheath tube segment is communicated with the inner cavity of the second sheath tube segment.

8. The rotational atherectomy structure according to claim 7, characterized in that: The first sheath tube segment comprises a connected diameter segment and a diameter-changing segment, the proximal end of the diameter-changing segment is connected to the distal end of the diameter segment, and the diameter of the diameter-changing segment gradually decreases from the proximal end to the distal end of the first sheath tube segment.

9. The rotational atherectomy structure according to claim 7, characterized in that: The outer sheath tube of the rotary grinding comprises an inner tube layer, a middle tube layer and an outer tube layer which are sequentially mounted from the inner layer to the outer layer. The inner tube layer is made of a low-friction polymer material, the middle tube layer is made of a metal material, and the outer tube layer is made of a high-toughness polymer material.

10. A rotational atherectomy catheter system, characterized in that: The rotational atherectomy catheter system comprises: The atherectomy structure according to any one of claims 1 to 9; A control host is drivingly connected to the atherectomy structure.

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