Intravascular rotary cutting device

Abstract

The invention relates to an intravascular rotary cutting device which comprises a sheathing canal, a rotating shaft, a tool bit assembly and a handle. The cutter head assembly comprises a first rotary cutter and a second rotary cutter, the second rotary cutter is provided with an arched structure, the arched height of the second rotary cutter can be increased or decreased under the action of external force, so that the second rotary cutter has a variable cutting diameter in a working state, the cutting diameter is not restrained by the inherent size of the sheathing canal any more, and the minimally invasive approach is kept while the cutting diameter is increased. A larger effective lumen and a better tissue treatment capability can be realized; in a non-working state, the device can be retracted into the sheath tube, so that the damage to the blood vessel is reduced; the handle comprises a shell, a rotary cutting driving assembly and a telescopic driving assembly; the near end of the sheathing canal or the shell is of a detachable sectional type structure, by means of the design of the detachable sectional type sheathing canal or the shell, the cutter head assembly and the rotating shaft can be independently withdrawn, meanwhile, a complete instrument channel is reserved, follow-up examination or treatment instruments can be directly introduced, and the whole system does not need to be completely withdrawn from the human body.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of medical devices, and in particular to an intravascular atherectomy device. BACKGROUND

[0002] Atherosclerosis is a common systemic vascular disease in the elderly, and its local manifestation in the limbs is arteriosclerosis obliterans. The main pathological features of this disease include the formation of atherosclerotic plaques in the intima, the degeneration or calcification of the middle layer, the secondary thrombosis in the lumen, and finally the destruction of the arterial wall structure, the stenosis or even complete occlusion of the lumen, and the occurrence of acute or chronic ischemic symptoms in the affected limbs, and even limb necrosis in severe cases.

[0003] In terms of clinical treatment, in addition to drug therapy, interventional surgery has become an important treatment method for arteriosclerosis obliterans. The traditional methods include balloon dilation and stent implantation. However, balloon dilation has limitations and cannot effectively overcome the elastic recoil of the blood vessel, nor can it avoid the occurrence of blood flow restriction dissection. The restenosis rate after stent implantation is high, and the long-term patency rate is not ideal. To overcome the above-mentioned defects, endoluminal reduction as a new type of interventional treatment has been gradually applied in clinical practice. This technology directly removes, removes or ablates plaques through special instruments, and is particularly suitable for severe calcification, multiple or transarticular vascular lesions, has the advantages of reducing the risk of dissection, permanently removing plaques, increasing the lumen volume, and inhibiting intimal hyperplasia, thereby significantly improving the long-term patency rate. In the existing endoluminal reduction technology, atherectomy devices have been widely used.

[0004] After the atherectomy device performs endoluminal reduction, it is usually necessary to introduce an inspection instrument (such as a detection catheter) to evaluate the internal condition of the blood vessel, or to implant a treatment instrument (such as a stent) for subsequent treatment. However, the cutting blade and rotating shaft of the existing atherectomy device cannot be withdrawn separately. Therefore, when subsequent detection or treatment is needed, the entire instrument must be completely withdrawn from the body, and then the corresponding inspection or treatment instrument must be introduced again. This operation process is cumbersome and time-consuming, and multiple instrument exchanges may increase the risk of intimal injury.

[0005] The cutting blade of the existing atherectomy device is usually designed to be exposed. During the process of pushing the instrument through the sheath tube to the lesion site, the edge of the blade head is easy to come into contact with the intima of the path blood vessel, causing unnecessary scraping or cutting injury to the non-target area tissue. This not only may cause vascular spasm, intimal tear or perforation, but also increases the risk of embolism and the probability of postoperative restenosis. In addition, due to the rigidity constraint of the existing delivery system, the outer diameter of the cutting blade must be strictly limited within the inner diameter of the sheath tube, resulting in a limited maximum expansion diameter. This structural limitation makes it difficult for the instrument to form a large enough effective lumen, especially when dealing with severe calcification, diffuse or multiple segment lesions, it is often impossible to achieve sufficient lumen reconstruction, the blood flow recovery effect is not ideal, and the long-term patency rate is affected.

[0006] The disclosure of the above Background Art is only for the purpose of facilitating the understanding of the concept and technical solutions of the present application, and does not necessarily belong to the prior art of the present application, nor necessarily give technical teaching; in the absence of explicit evidence that the above background art has been disclosed before the filing date of the present application, the above background art should not be used to evaluate the novelty and inventiveness of the present application. SUMMARY

[0007] The technical problem to be solved by the present application is to provide an intravascular rotary atherectomy device, whose rotary shaft and cutter head assembly can be withdrawn from the sheath separately, leaving an intact instrument channel for subsequent access of inspection or treatment instruments, and which is convenient and safe to operate.

[0008] To achieve the above object, the technical solution adopted by the present application is:

[0009] The present application provides an intravascular rotary atherectomy device, comprising a sheath, a rotary shaft arranged in the sheath, a cutter head assembly connected to the distal end of the rotary shaft, and a handle connected to the proximal end of the sheath,

[0010] The cutter head assembly has an initial state of being accommodated in the sheath and a working state of extending out of the sheath, and comprises a first rotary cutter and a second rotary cutter; the cutting diameter of the first rotary cutter is not greater than the inner diameter of the sheath; the second rotary cutter is connected between the first rotary cutter and the rotary shaft, and has at least two parts arranged on both sides of the rotary shaft, and has an arching structure arching towards the outside of the rotary shaft;

[0011] The second rotary cutter can increase or decrease the arching height under the action of external force, so as to have a variable cutting diameter in the working state and be retractable into the sheath in the initial state; the maximum cutting diameter is greater than the outer diameter of the sheath;

[0012] The handle comprises a housing, a rotary cutting drive assembly for driving the rotary shaft to rotate about its own axis, and an extension drive assembly; the extension drive assembly comprises an extension drive member slidingly arranged in the housing in the axial direction, and a first motion conversion member connected between the extension drive member and the rotary shaft; the extension drive member is configured to drive the rotary shaft to move in the axial direction through the first motion conversion member, so as to switch the cutter head assembly between the initial state and the working state; the first motion conversion member is configured to transmit the axial motion and isolate the transmission of the rotary motion to the extension drive member;

[0013] The proximal end of the sheath is of a detachable segmented structure; or, the housing is of a detachable segmented structure, and the segmented structure is located at the distal end of the extension drive assembly and the rotary cutting drive assembly and does not interfere with each other.

[0014] In some embodiments, the segmented structure employs a threaded connection. Further, the sheath includes a first sheath segment and a second sheath segment, the first sheath segment constituting a main body portion of the sheath, and the second sheath segment being connected between the first sheath segment and the housing, both detachably connected through a threaded connection.

[0015] In some embodiments, the second rotary cutter includes a first cutting portion and a second cutting portion; a distal end of the first cutting portion is connected to the first rotary cutter, and the first cutting portion extends obliquely from distal to proximal towards a direction away from the rotation axis;

[0016] a distal end of the second cutting portion is connected to a proximal end of the first cutting portion, and a proximal end of the second cutting portion is connected to a distal end of the rotation axis; the second cutting portion extends obliquely from distal to proximal towards a direction close to the rotation axis; and a connection between the first cutting portion and the second cutting portion forms the arch structure.

[0017] In some specific embodiments, a distal end of the second rotary cutter is fixedly connected to the rotation axis, and a proximal end of the second rotary cutter is a free end and movable; when the second rotary cutter extends out of the rotation axis, the proximal end of the second rotary cutter moves towards the distal end under the action of a self-memory effect, causing the arch structure to expand outward.

[0018] In other specific embodiments, a proximal end of the second rotary cutter is fixedly connected to the rotation axis, and a distal end of the second rotary cutter is a free end and movable.

[0019] In some other embodiments, the second rotary cutter is in a spiral shape around a circumferential side of the rotation axis, a distal end of the second rotary cutter is connected to a proximal end of the first rotary cutter, and a proximal end of the second rotary cutter is connected to a distal end of the rotation axis; the spiral shape of the second rotary cutter constitutes the arch structure.

[0020] In some embodiments, the rotary cutting device further includes a limiting member fixedly arranged on the rotation axis and located between the first rotary cutter and the rotation axis; the limiting member is configured to abut against the first rotary cutter to limit the second rotary cutter from expanding outward beyond a preset range.

[0021] In some other embodiments, the rotary cutting device further comprises a pulling member movably arranged in the sheath and fixedly connected to the first rotary cutting knife at the distal end, a pulling driving member axially slidingly arranged on the housing, and a second motion conversion member connected to the pulling driving member and fixedly connected to the pulling member; wherein the pulling driving member is configured to drive the pulling member to move axially through the second motion conversion member, so as to increase or decrease the cutting diameter of the second rotary cutting knife; the second motion conversion member is configured to isolate the transmission of the rotary motion of the pulling member to the pulling driving member while transmitting the axial motion. Preferably, the second motion conversion member is a bearing. The pulling driving member is at least partially exposed outside the housing, and the exposed part is provided with an ergonomic operation part. The rotary shaft has a hollow structure extending in the axial direction, and the pulling member is slidably arranged in the hollow structure.

[0022] In some embodiments, the first motion conversion member is a bearing.

[0023] In some embodiments, the telescopic driving member is a ring-shaped member coaxial with the rotary shaft, and the outer periphery of the ring-shaped member is provided with threads; the telescopic driving assembly further comprises a telescopic operation member movably arranged on the housing and at least partially exposed, and the telescopic operation member is threadedly engaged with the telescopic driving member.

[0024] In some embodiments, the rotary cutting device further comprises a hard circular ring fixedly arranged at the distal end of the sheath.

[0025] In some embodiments, the rotary cutting device further comprises an imaging assembly arranged at the distal end of the rotary shaft and located between the first rotary cutting knife and the rotary shaft, and a connecting line arranged in the rotary shaft, with the distal end connected to the imaging assembly and the proximal end connected to an external host computer.

[0026] In some embodiments, the rotary cutting driving assembly comprises a driving motor, a driving wheel connected to the output shaft of the driving motor and coaxial with the output shaft, and the driving wheel is engaged with the outside of the proximal end of the rotary shaft.

[0027] In some other embodiments, the rotary cutting driving assembly comprises a driving motor, a transmission mechanism connected between the output shaft of the driving motor and the rotary shaft, and the transmission mechanism, the rotary shaft and the output shaft of the driving motor are coaxial.

[0028] The application also provides an intravascular rotary atherectomy device, comprising a sheath, a rotary shaft arranged in the sheath, a cutter head assembly connected to the distal end of the rotary shaft, and a handle connected to the proximal end of the sheath, wherein the handle comprises a housing and a rotary atherectomy driving assembly configured to drive the rotary shaft to rotate around its own axis, the rotary shaft is detachably connected to the housing and can drive the cutter head assembly to move out of the channel formed by the sheath and the housing under the action of an external force.

[0029] In some embodiments, the proximal end of the rotary shaft is provided with a protrusion, the housing is provided with a ring-shaped recess matched with the protrusion, and the distal end of the protrusion and / or the ring-shaped recess is provided with a guide slope.

[0030] In some embodiments, the rotary atherectomy driving assembly comprises a driving motor, a driving wheel connected to and coaxial with the output shaft of the driving motor, and the driving wheel is engaged with the outer side of the proximal end of the rotary shaft.

[0031] In some other embodiments, the rotary atherectomy driving assembly comprises a driving motor and a transmission mechanism connected between the output shaft of the driving motor and the rotary shaft, and the transmission mechanism, the rotary shaft and the output shaft of the driving motor are coaxial.

[0032] In some embodiments, the rotary atherectomy device further comprises an imaging assembly arranged at the distal end of the rotary shaft and located on the cutter head assembly, and a connecting line arranged in the rotary shaft, wherein the distal end of the connecting line is connected to the imaging assembly, and the proximal end of the connecting line is used to connect to an external host.

[0033] Thanks to the above technical solutions, the application has at least one of the following advantages compared with the prior art:

[0034] By adopting the detachable segmented sheath or housing design, the cutter head assembly and the rotary shaft can be independently withdrawn, while the complete instrument channel is reserved. The channel can be used to directly introduce subsequent inspection or treatment instruments, without the need to completely withdraw the entire system from the human body, thereby simplifying the operation process, shortening the operation time, and reducing the risk of tissue damage caused by multiple instrument exchanges.

[0035] The cutter head assembly of the rotary cutting device has the functions of extension and variable diameter, can be completely accommodated in the sheath, can be controlled through the handle, and can realize the extension and retraction of the cutter head assembly in the sheath. In the cutting operation, the cutter head assembly can be extended out of the sheath and perform efficient and controllable cutting on the target tissue; in the non-working state (such as the in-vessel travel or positioning process), the cutter head assembly can be completely retracted into the sheath, thereby effectively avoiding scratching or damaging the normal tissues along the way, and significantly improving the safety of the surgical process and the passability of the interventional operation.

[0036] Further, the cutter head assembly can also actively or passively change its working diameter according to the needs of the operation. The maximum cutting diameter can be expanded to be greater than the outer diameter of the sheath, thereby obtaining greater cutting range and operation efficiency; the minimum cutting diameter can be contracted to be not greater than the inner diameter of the sheath, so as to ensure that the cutter head can be smoothly and smoothly retracted into the sheath. The variable diameter design makes the cutting diameter no longer constrained by the inherent size of the sheath, while maintaining the minimally invasive approach, realizing greater effective lumen and better tissue processing capacity. BRIEF DESCRIPTION OF DRAWINGS

[0037] Figure 1 A structure schematic view of a rotary cutting device provided for example 1 is shown in the figure;

[0038] Figure 2 A cross-sectional view of a cutter head assembly provided for example 1 in a working state is shown in the figure;

[0039] Figure 3 A cross-sectional view of a cutter head assembly provided for example 1 in an initial state is shown in the figure;

[0040] Figure 4 A cross-sectional view of another cutter head assembly provided for example 1 in a working state is shown in the figure;

[0041] Figure 5 A cross-sectional view of another cutter head assembly provided for example 1 in an initial state is shown in the figure;

[0042] Figure 6 A cross-sectional view of another cutter head assembly provided for example 1 in a working state is shown in the figure;

[0043] Figure 7 A cross-sectional view of another cutter head assembly provided for example 1 in an initial state is shown in the figure;

[0044] Figure 8 A cross-sectional view of a handle provided for example 1 is shown in the figure;

[0045] Figure 9 A cross-sectional view of another handle provided for example 1 is shown in the figure;

[0046] Figure 10 A structure schematic view of a rotary shaft provided for example 1 is shown in the figure;

[0047] Figure 11 This is a schematic diagram of the structure of a rotary cutting device provided in Embodiment 2;

[0048] Figure 12 A cross-sectional view of the handle provided in Embodiment 2;

[0049] Figure 13 A cross-sectional view of another handle provided in Embodiment 2;

[0050] Figure 14 This is a schematic diagram of the structure of the rotating shaft provided in Embodiment 2;

[0051] Figure 15 This is a schematic diagram of another rotating shaft provided in Embodiment 2;

[0052] Among them, 1. sheath; 11. first sheath segment; 12. second sheath segment;

[0053] 2. Rotating shaft; 21. Bourdon tube; 211. Hollow structure; 22. Sleeve; 221. Slide groove; 222. Protrusion;

[0054] 3. Blade assembly; 31. First rotary cutter; 311. Blade holder; 32. Second rotary cutter; 321. First cutting section; 322. Second cutting section; 323. Arched structure;

[0055] 4. Limiting components;

[0056] 5. Pulling components;

[0057] 6. Handle; 61. Housing; 62. Telescopic drive assembly; 621. Telescopic drive component; 622. First motion conversion component; 623. Telescopic operating component; 63. Pulling drive component; 631. Connecting part; 632. Operating part; 64. Second motion conversion component; 65. Drive wheel;

[0058] 7. Imaging components; 71. Connecting cables;

[0059] 8. Hard circular ring. Detailed Implementation

[0060] The present invention will be further described below with reference to embodiments. However, the present invention is not limited to the following embodiments. The implementation conditions used in the embodiments can be further adjusted according to different requirements of specific applications, and the implementation conditions not specified are conventional conditions in the industry. The technical features involved in the various embodiments of the present invention can be combined with each other as long as they do not conflict with each other.

[0061] In the following, only certain exemplary embodiments are simply described. As those skilled in the art can recognize, the described embodiments can be modified in various different ways without departing from the spirit or scope of the embodiments of the present application. Therefore, the drawings and descriptions are considered to be exemplary in nature rather than limiting.

[0062] In the description of the present application, it needs to be understood that the distal end refers to the end of the instrument or component far away from the operator, the proximal end refers to the end of the instrument or component close to the operator; the axial direction refers to the direction parallel to the center line of the distal end and the proximal end of the instrument or component; the inner and outer are the positions defined relative to the center of the instrument or component, wherein the inner is the position close to the center of the instrument or component, and the outer is the position away from the center of the instrument or component; the up and down refer to the position of the instrument in the actual use or working state. The above position words are only for the convenience of describing the embodiments of the present application and simplifying the description, and are not intended to indicate or imply that the devices or elements referred to must have a particular position, be constructed and operated in a particular position, and therefore cannot be understood as a limitation on the embodiments of the present application.

[0063] In addition, the terms "first" and "second" are only for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the technical features indicated. Therefore, the features defined as "first" and "second" can explicitly or implicitly include one or more of the features. In the description of the embodiments of the present application, the meaning of "a plurality of" is two or more, unless otherwise specifically limited.

[0064] In the description of the present application, it needs to be understood that, unless otherwise specifically specified and limited, the terms "mounting", "connecting", "connection" should be understood in a broad sense, for example, it can be fixed connection, or detachable connection, or integrally connected; it can be directly connected, or indirectly connected through an intermediate medium, or the communication inside two elements. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances, and cannot be understood as a limitation on the present application.

[0065] The following disclosure provides many different embodiments or examples for implementing different structures of the embodiments of the present application. In order to simplify the disclosure of the embodiments of the present application, the components and settings of specific examples are described in the following. Of course, they are only examples, and the purpose is not to limit the embodiments of the present application. In addition, the embodiments of the present application can refer to the same reference numerals and / or reference letters in different examples, and such repetition is for the purpose of simplification and clarity, and does not indicate the relationship between the various embodiments and / or settings discussed.

[0066] The embodiments of the present application will be described in detail below with reference to the accompanying drawings.

[0067] Embodiment 1: The present embodiment provides an intravascular atherectomy device, as shown in the accompanying drawings, which comprises a sheath tube 1, a rotating shaft 2 movably arranged in the sheath tube 1, a cutter head assembly 3 connected to the distal end of the rotating shaft 2, and a handle 6 connected to the proximal end of the sheath tube 1. Figure 1

[0068] The cutter head assembly 3 has an initial state (non-working state) of being accommodated in the sheath tube 1 and a working state of extending out of the sheath tube 1, and comprises a first rotary cutter 31 and a second rotary cutter 32. The cutting diameter of the first rotary cutter 31 does not exceed the inner diameter of the sheath tube 1, so that it can be smoothly withdrawn into the sheath tube 1. The second rotary cutter 32 is connected between the first rotary cutter 31 and the rotating shaft 2, and has at least two parts arranged on both sides of the rotating shaft 2. The second rotary cutter 32 has an arch structure 323 arching towards the outside of the rotating shaft 2. The second rotary cutter 32 can increase or decrease the arching height under the action of external force, so as to have a variable cutting diameter in the working state and be retractable into the sheath tube 1 in the initial state, and the maximum cutting diameter is greater than the outer diameter of the sheath tube 1.

[0069] The first rotary cutter 31 can open a safe initial channel in the blood vessel with a size not greater than the inner diameter of the sheath tube 1, ensuring that the blood vessel wall will not be damaged due to the excessively large cutting diameter in the initial stage of the operation. The second rotary cutter 32 can expand outward under the action of external force or restore the outward expansion under the action of its own memory effect, achieving extensive removal of the plaque area larger than the diameter of the sheath tube 1. The design has at least the following advantages: first, it can effectively treat large-sized blood vessels while maintaining a small delivery outer diameter, without relying on a large-sized sheath tube 1, significantly reducing the surgical approach trauma; second, it significantly increases the amount of plaque removed in a single operation, avoiding multiple instrument changes during the operation, which not only improves the operation efficiency but also reduces the operation complexity, and is particularly suitable for severe calcification or diffuse lesions.

[0070] In the present embodiment, the second rotary cutter 32 comprises a first cutting part 321 and a second cutting part 322. The distal end of the first cutting part 321 is fixedly connected to the first rotary cutter 31, and the proximal end thereof is connected to the distal end of the second cutting part 322, while the proximal end of the second cutting part 322 is connected to the distal end of the rotating shaft 2. The first cutting part 321 extends obliquely from the distal end to the proximal end towards the direction away from the rotating shaft 2, and in contrast, the second cutting part 322 extends obliquely from the distal end to the proximal end towards the direction close to the rotating shaft 2. The connection between the first cutting part 321 and the second cutting part 322 forms an arch structure 323, which is generally V-shaped. The specific shape of the first cutting part 321 and the second cutting part 322 includes but is not limited to straight line or wave shape, and other suitable continuous curved structures can also be used. The selection of the specific shape can be optimized according to the characteristics of the target tissue, so as to achieve the best cutting efficiency and maneuverability.

[0071] Further, as shown in the accompanying drawings, Figure 4 ​and Figure 5 As shown, the proximal end of the second rotary cutter 32 is fixedly connected to the rotation axis 2, while its distal end is a free and movable end. Thus, when the cutter head assembly 3 is in operation and abuts against the target tissue (such as a distal plaque), the first rotary cutter 31 experiences resistance and tends to move towards the rotation axis 2. At this time, the included angle of the V-shaped arch decreases, and the arch height increases, thereby expanding the cutting diameter and achieving efficient removal of a wider plaque area. After cutting, the external force is removed, and the second rotary cutter 32 returns to its original shape under its own elasticity. Simultaneously, the inclined structure of the second cutting section 322 towards the axis provides guidance for the retraction process, ensuring that the cutter head assembly 3 can smoothly and steadily retract into the sheath 1, avoiding secondary damage to the vessel wall. In another embodiment, such as... Figure 6 and Figure 7 As shown, the distal end of the second rotary cutter 32 is fixedly connected to the rotating shaft 2, while its proximal end is a free and movable end. When the second rotary cutter 32 extends outward from the rotating shaft 2, its proximal end moves towards the distal end under the effect of its own memory effect, causing the arched structure 323 to unfold outward. Furthermore, during the cutting process, the centrifugal force generated by rotation can further increase its arching degree. After cutting, the second rotary cutter 32 can retract into the sheath 1 under the constraint of the sheath 1. Similarly, the inclined structure of the second cutting part 322 towards the axis provides guidance for the retraction process. The proximal end of the second rotary cutter 32 is preferably slidably connected to the rotating shaft 2 axially via a sleeve. Preferably, a hard ring 8 can be installed at the distal end of the sheath 1 to prevent damage to the sheath 1 when the cutter head assembly 3 retracts into the sheath 1. The hard ring 8 has a higher hardness than the distal end of the sheath 1, and its material includes, but is not limited to, stainless steel, nickel-titanium alloy, polyimide, etc. The first cutting part 321 and the second cutting part 322 are preferably integrally formed structures, and are respectively fixedly connected to the first rotary cutter 31 and the rotating shaft 2. The fixed connection method includes, but is not limited to, welding and bonding. The second rotary cutter 32 is made of metal, including but not limited to stainless steel and nickel-titanium alloy.

[0072] In other implementations, such as Figure 2 and Figure 3 As shown, the second rotary cutter 32 can also be spirally wound around the circumference of the rotating shaft 2, with its distal end connected to the proximal end of the first rotary cutter 31 and its proximal end connected to the distal end of the rotating shaft 2. This spiral structure forms an arched structure 323. The number of spiral turns can be designed according to actual clinical needs, preferably 1 to 3 turns. Unless otherwise specified, one turn is defined as the second rotary cutter 32 rotating 360° around the rotating shaft 2.

[0073] To avoid overexpansion of the second rotary cutter 32, the rotary cutting device further comprises a limiting member 4. The limiting member 4 is fixedly arranged on the rotary shaft 2 and located between the first rotary cutter 31 and the rotary shaft 2. The limiting member 4 is configured to abut against the first rotary cutter 31 to limit the outward expansion of the second rotary cutter 32 beyond a preset range, thereby further ensuring safety. Of course, in other embodiments, a pulling member 5 can be used instead of the limiting member 4 to more accurately control the expansion diameter of the second rotary cutter 32. Specifically, the pulling member 5 is movably arranged in the sheath 1, and its distal end is fixedly connected to the first rotary cutter 31. By driving the pulling member 5 to move axially toward the proximal end, the pulling member 5 drives the first rotary cutter 31 to move synchronously, the distance between the first rotary cutter 31 and the rotary shaft 2 gradually decreases, the included angle of the V-shaped arching portion decreases, and the arching degree increases, thereby expanding the cutting diameter. Conversely, by driving the pulling member 5 to move axially toward the distal end, the pulling member 5 drives the first rotary cutter 31 to move synchronously, the distance between the first rotary cutter 31 and the rotary shaft 2 gradually increases, the included angle of the V-shaped arching portion increases, and the arching degree decreases, thereby reducing the cutting diameter. When the pulling member 5 is provided, the handle 6 needs to be correspondingly provided with a pulling driving member 63 and a second motion conversion member 64, which will be described in detail below.

[0074] To enhance cutting stability and balance, a plurality of second rotary cutters 32 are preferably arranged symmetrically. The second rotary cutters 32 are preferably 2-4, and in the present embodiment, the second rotary cutters 32 are 2.

[0075] The cutting diameter of the first rotary cutter 31 increases from the distal end to the proximal end, and the proximal end cutting diameter does not exceed the inner diameter of the sheath 1. Specifically, the first rotary cutter 31 includes at least two cutting blades. These cutting blades are arranged circumferentially and enclosed to form a geometric structure with a small distal end diameter and a large proximal end diameter, thereby forming a conical or approximately conical cutting profile. As a preferred, the cutting blades are mounted on a cutter seat 311.

[0076] The handle 6 includes a housing 61, a rotary cutting driving assembly, and a telescopic driving assembly 62.

[0077] The rotary cutting driving assembly is drivingly connected to the proximal end of the rotary shaft 2 for driving the rotary shaft 2 to rotate about its own axis, thereby rotating the target tissue such as plaque, thrombus, etc. The rotary cutting driving assembly can refer to the existing technology in the art.

[0078] The telescopic driving assembly 62 comprises a telescopic driving member 621 axially slidingly arranged on the housing 61, and a first motion conversion member 622 connected between the telescopic driving member 621 and the rotating shaft 2, the telescopic driving member 621 being configured to drive the rotating shaft 2 to move axially through the first motion conversion member 622, so as to switch the cutting head assembly 3 between the initial state and the working state. The first motion conversion member 622 is configured to isolate the transmission of the rotating motion of the rotating shaft 2 to the telescopic driving member 621 while transmitting the axial motion. The second rotary cutting knife 32 can be retracted into the sheath 1, which facilitates safe entry into the body or withdrawal from the body, thereby effectively avoiding scratching or damaging normal tissues along the way, and significantly improving the safety of the surgical process and the passability of the interventional operation.

[0079] In the embodiment, as shown in Figure 7 The telescopic driving member 621 is a ring-shaped member coaxial with the rotating shaft 2, and a thread is arranged on the outer periphery of the telescopic driving member 621. The telescopic driving assembly 62 further comprises a telescopic operating member 623 movably mounted on the housing 61 and at least partially exposed, and the telescopic operating member 623 is threadedly connected with the telescopic driving member 621. When the operator rotates the telescopic operating member 623, the screw pair converts the rotating motion into linear motion to drive the telescopic driving member 621 to move axially. Since the telescopic driving member 621 is connected with the internal rotating shaft 2 through the first motion conversion member 622, the axial motion of the telescopic driving member 621 will drive the rotating shaft 2 to move axially synchronously, so as to finally realize the stable and controllable extension of the cutting head assembly 3 out of the sheath 1 into the working state, or the smooth retraction of the cutting head assembly 3 into the sheath 1 for transportation or withdrawal. The first motion conversion member 622 ensures the smooth axial movement while the rotating shaft 2 rotates at a high speed. The first motion conversion member 622 is a bearing. In other embodiments, the telescopic driving member 621 and the rotating shaft 2 can also be movably connected in any one of the following manners: key groove, spline, magnetic coupling.

[0080] Similarly to the telescopic driving assembly 62, as shown in Figure 6As shown (the telescopic driving assembly 62 is not shown in the figure), the pulling driving member 63 is arranged on the shell 61 in axial sliding manner, and the second motion conversion member 64 is connected to the pulling driving member 63 and fixedly connected with the pulling member 5. Among them, the pulling driving member 63 is configured to drive the pulling member 5 to move in axial direction through the second motion conversion member 64, so as to increase or reduce the cutting diameter of the second rotary cutter 32; the second motion conversion member 64 is configured to isolate the transmission of the rotary motion of the pulling member 5 to the pulling driving member 63 while transmitting the axial motion. The second motion conversion member 64 is preferably a bearing. Of course, the pulling driving member 63 and the pulling member 5 can also be any one of the following active matching modes: key groove, spline, magnetic coupling. The pulling driving member 63 is at least partially exposed to the shell 61, and the exposed part is provided with an ergonomic operation part 632. When the rotary cutting device has the pulling member 5, the pulling driving member 63 and the second motion conversion member 64 are correspondingly arranged on the shell 61; wherein the pulling driving member 63 can be selectively arranged at the distal end or the proximal end of the telescopic driving assembly 62, without specific limitation.

[0081] The rotary shaft 2 comprises a spring tube 21 and a sleeve 22 coaxial with the spring tube 21 and fixedly connected to the proximal end of the spring tube 21. The spring tube 21 is a multi-layer multi-strand spring tube 21, and the material thereof is metal, including but not limited to stainless steel, nickel-titanium alloy. The rotary shaft 2 preferably has a hollow structure 211 extending in axial direction, and when the rotary cutting device has the pulling member 5, the pulling member 5 is slidably arranged in the hollow structure 211, and the proximal end of the sleeve 22 is correspondingly provided with a sliding groove 221 (as shown) extending in axial direction. Figure 8 As shown, one end of the connecting part 631 is fixedly connected to the pulling member 5, and the other end extends out of the sliding groove 221 and is connected to the second motion conversion member 64. When the pulling driving member 63 drives the second motion conversion member 64 to slide in axial direction, the second motion conversion member 64 synchronously slides with the pulling member 5 through the connecting part 631.

[0082] In this embodiment, as shown, Figure 1 As shown, the proximal end of the sheath tube 1 is a detachable segmented structure, specifically comprising a first sheath tube segment 11 and a second sheath tube segment 12. Among them, the first sheath tube segment 11 constitutes the main part of the sheath tube 1, and the second sheath tube segment 12 is connected between the first sheath tube segment 11 and the shell 61, and the two are detachably connected through threads. When the rotary cutting device completes the intracavitary volume reduction operation, the second sheath tube segment 12 can be unscrewed from the first sheath tube segment 11, so that the cutter head assembly 3 and the rotary shaft 2 can be smoothly withdrawn. At this time, the first sheath tube segment 11 is still retained in the human body, maintaining the complete instrument channel, facilitating the subsequent interventional operation (such as the placement of a detection catheter or a stent) to be directly performed without the need to establish a channel again. In other embodiments, the shell 61 can also be provided as a detachable segmented structure, and the segmented structure is located at the distal end of the telescopic driving assembly 62 and the rotary cutting driving assembly and does not interfere with each other. The segmented structure adopts a threaded connection mode, including but not limited to.

[0083] To enable real-time and precise intravascular positioning, the rotary cutting device also includes an imaging component 7 and a connecting line 71. The imaging component 7 is located at the distal end of the rotating shaft 2, between the first rotary cutting blade 31 and the rotating shaft 2. The connecting line 71 passes through the rotating shaft 2, with its distal end connected to the imaging component 7 and its proximal end used to connect to an external host. As an example, the imaging component 7 can be one or more of a miniature camera, an ultrasound imaging device, an electromagnetic imaging device, or a laser imaging device. The imaging component 7 is preferably an ultrasound imaging device, which can use ultrasound transmitting and receiving devices to position instruments in the blood vessel, providing real-time and precise ultrasound image visualization. This allows for accurate assessment of lesions and guidance on the relative positions of the catheter, blood vessel, and lesion, effectively reducing damage to the blood vessel during the opening process and improving safety. As a further preferred embodiment, the imaging plane of the imaging component 7 forms a certain angle with the axial direction of the rotating shaft 2, preferably between 5° and 45°. The imaging component 7 also includes at least one through-hole, allowing the hollow structure 211 of the rotating shaft 2 to communicate with an external blood vessel. This through-hole can serve as an infusion port for saline, contrast agents, etc., and can also be used to flush the field of view during observation by the imaging component 7. Correspondingly, the handle 6 can also be equipped with infusion channels, aspiration channels, etc., according to actual needs, as detailed in the prior art.

[0084] Example 2

[0085] An intravascular rotary cutting device, such as Figure 9 As shown, it includes a sheath 1, a rotating shaft 2 disposed within the sheath 1, a blade assembly 3 connected to the distal end of the rotating shaft 2, and a handle 6 connected to the proximal end of the sheath 1. The handle 6 includes a housing 61 and a rotary cutting drive assembly, which is configured to drive the rotating shaft 2 to rotate around its own axis. The rotating shaft 2 is detachably connected to the housing 61 and can be moved out of the channel formed by the sheath 1 and the housing 61 when an external force is applied. After the rotary cutting device completes the intracavitary volume reduction operation, the blade assembly 3 and the rotating shaft 2 are withdrawn by applying external force, while the sheath 1 remains in the body, maintaining an intact instrument channel. This facilitates subsequent interventional operations (such as the placement of a probe catheter or stent) without the need to re-establish the channel, making it more convenient and safer.

[0086] Further, the rotating shaft 2 comprises a spring tube 21 and a sleeve 22 coaxial with the spring tube 21 and fixedly connected to the spring tube 21 at the proximal end of the spring tube 21. The spring tube 21 is a multi-layered and multi-stranded spring tube 21 made of metal, including but not limited to stainless steel and nickel-titanium alloy. The sleeve 22 is provided with a protrusion 222, and the proximal end of the sleeve 22 extends out of the housing 61. The housing 61 is provided with an annular recess which cooperates with the protrusion 222. The distal end of the protrusion 222 and / or the annular recess is provided with a guide slope. When it is necessary to withdraw, the sleeve 22 is pulled backward, and the protrusion 222 is separated from the annular recess under the guidance of the guide slope. Then, under the action of the continuous pulling force, the entire rotating shaft 2 can drive the cutter head assembly 3 to be withdrawn from the channel formed by the sheath tube 1 and the housing 61. As an example, the protrusion 222 can be two symmetrical flat keys, or can be an annular protrusion.

[0087] The rotary cutting driving assembly comprises a driving motor, a driving wheel 65 connected to the output shaft of the driving motor and coaxial with the output shaft, and the driving wheel 65 is engaged with the outer side of the sleeve 22. In the embodiment, the protrusion 222 is an annular protrusion, and the outer side of the protrusion 222 is provided with a tooth groove extending in the axial direction and matched with the driving wheel 65. In this way, the driving motor is located outside the sleeve 22, and the sleeve 22 can be directly pulled without disassembling the motor, so that the rotating shaft 2 and the cutter head assembly 3 can be pulled out as a whole, which is more convenient. Of course, in other embodiments, the rotary cutting driving assembly can also be composed of a driving motor, a transmission mechanism connected between the output shaft of the driving motor and the rotating shaft 2, and the transmission mechanism, the rotating shaft 2 and the output shaft of the driving motor are coaxial. The transmission mechanism can refer to the prior art.

[0088] In order to position in the blood vessel lumen in real time and accurately, the rotary cutting device further comprises an imaging assembly 7 and a connecting line 71. The imaging assembly 7 is arranged at the distal end of the rotating shaft 2 and located at the proximal end of the cutter head assembly 3 or in the cutter head assembly 3. The connecting line 71 is arranged in the rotating shaft 2, and the distal end of the connecting line 71 is connected to the imaging assembly 7, and the proximal end of the connecting line 71 is used to connect to an external host. The imaging assembly 7 is the same as the embodiment 1, and will not be described here.

[0089] In the embodiment, the cutter head assembly 3 comprises at least two cutting blades. The cutting blades are arranged in a circle and form a geometric structure with a small diameter at the distal end and a large diameter at the proximal end, so as to form a conical or approximately conical cutting profile. As a preferred, the cutting blades are mounted on the cutter seat 311.

[0090] The above detailed description of the present application is intended to enable the person skilled in the art to understand and implement the present application, and cannot limit the protection scope of the present application. Any equivalent changes or modifications made according to the spirit and principle of the present application shall be covered within the protection scope of the present application.

Claims

1. An intravascular rotary cutting device, comprising a sheath (1), a rotating shaft (2) disposed within the sheath (1), a blade assembly (3) connected to the distal end of the rotating shaft (2), and a handle (6) connected to the proximal end of the sheath (1), characterized in that: The blade assembly (3) has an initial state housed within the sheath (1) and a working state extending outside the sheath (1), including a first rotary cutter (31) and a second rotary cutter (32); the cutting diameter of the first rotary cutter (31) does not exceed the inner diameter of the sheath (1); the second rotary cutter (32) is connected between the first rotary cutter (31) and the rotating shaft (2), and has at least two blades respectively disposed on both sides of the rotating shaft (2), and has an arched structure (323) arching outward toward the rotating shaft (2); The second rotary cutter (32) can increase or decrease its arch height under external force so as to have a variable cutting diameter in the working state and can retract the sheath (1) in the initial state; its maximum cutting diameter is greater than the outer diameter of the sheath (1); The handle (6) includes a housing (61), a rotary cutting drive assembly for driving the rotating shaft (2) to rotate about its own axis, and a telescopic drive assembly (62). The telescopic drive assembly (62) includes a telescopic drive member (621) slidably disposed on the housing (61) along the axis, and a first motion conversion member (622) connecting the telescopic drive member (621) and the rotating shaft (2). The telescopic drive member (621) is configured to drive the rotating shaft (2) to move axially through the first motion conversion member (622) so that the cutter head assembly (3) switches between an initial state and a working state. The first motion conversion member (622) is configured to transmit axial motion and isolate the transmission of rotational motion to the telescopic drive member (621). The proximal end of the sheath (1) is a detachable segmented structure; or, the housing (61) is a detachable segmented structure, and the segmented structure is located at the distal end of the telescopic drive assembly (62) and the rotary cutting drive assembly and does not interfere with each other.

2. The rotary cutting device according to claim 1, characterized in that: The sheath (1) includes a first sheath section (11) and a second sheath section (12). The first sheath section (11) constitutes the main body of the sheath (1), and the second sheath section (12) is connected between the first sheath section (11) and the housing (61), and the two are detachably connected by threads.

3. The rotary cutting device according to claim 1, characterized in that: The second rotary cutter (32) includes a first cutting section (321) and a second cutting section (322); The distal end of the first cutting part (321) is connected to the first rotary cutter (31), and the first cutting part (321) extends obliquely from far to near in a direction away from the rotation axis (2); The distal end of the second cutting part (322) is connected to the proximal end of the first cutting part (321), and its proximal end is connected to the distal end of the rotating shaft (2). The second cutting part (322) extends obliquely from far to near towards the rotating shaft (2). The arched structure (323) is formed at the connection between the first cutting part (321) and the second cutting part (322).

4. The rotary cutting device according to claim 3, characterized in that: The distal end of the second rotary cutter (32) is fixedly connected to the rotating shaft (2), and its proximal end is a free end and can move; When the second rotary cutter (32) extends out of the rotating shaft (2), its proximal end moves toward the distal end under the action of its own memory effect, causing the arched structure (323) to unfold outward.

5. The rotary cutting device according to claim 3, characterized in that: The proximal end of the second rotary cutter (32) is fixedly connected to the rotating shaft (2), and its distal end is a free end that can move.

6. The rotary cutting device according to claim 1, characterized in that: The second rotary cutter (32) is spirally wrapped around the circumference of the rotating shaft (2), and its distal end is connected to the proximal end of the first rotary cutter (31), and its proximal end is connected to the distal end of the rotating shaft (2). The spiral structure of the second rotary cutter (32) constitutes the arched structure (323).

7. The rotary cutting device according to claim 5 or 6, characterized in that: The rotary cutting device further includes a limiting member (4), which is fixedly disposed on the rotating shaft (2) and located between the first rotary cutting blade (31) and the rotating shaft (2); the limiting member (4) is configured to abut against the first rotary cutting blade (31) to limit the second rotary cutting blade (32) from expanding outward beyond a preset range.

8. The rotary cutting device according to claim 5 or 6, characterized in that: The rotary cutting device further includes a pulling member (5) movably disposed inside the sheath (1) and fixedly connected at its distal end to the first rotary cutting blade (31), a pulling drive member (63) slidably disposed on the housing (61) along the axial direction, and a second motion conversion member (64) connected to the pulling drive member (63) and fixedly connected to the pulling member (5); The traction drive (63) is configured to drive the traction member (5) to move axially via the second motion converter (64) so ​​that the cutting diameter of the second rotary cutter (32) increases or decreases; the second motion converter (64) is configured to isolate the transmission of the rotational motion of the traction member (5) to the traction drive (63) while transmitting the axial motion.

9. The rotary cutting device according to claim 8, characterized in that: The second motion conversion element (64) is a bearing; and / or, The traction drive (63) is at least partially exposed outside the housing (61), and the exposed portion is provided with an ergonomic operating part (632); and / or, The rotating shaft (2) has a hollow structure (211) extending along the axial direction, and the traction member (5) is slidably inserted into the hollow structure (211).

10. The rotary cutting device according to claim 1, characterized in that: The first motion conversion element (622) is a bearing; and / or, The telescopic drive member (621) is a ring-shaped member coaxial with the rotating shaft (2) and has threads on its outer periphery; the telescopic drive assembly (62) also includes a telescopic operating member (623) movably mounted on the housing (61) and at least partially exposed, the telescopic operating member (623) being threadedly engaged with the telescopic drive member (621).

11. The rotary cutting device according to claim 1, characterized in that: The rotary cutting device also includes a hard ring (8), which is fixedly installed at the distal end of the sheath (1).

12. The rotary cutting device according to claim 1, characterized in that: The rotary cutting device further includes an imaging component (7) and a connecting line (71). The imaging component (7) is located at the far end of the rotating shaft (2) and between the first rotary cutting blade (31) and the rotating shaft (2). The connecting line (71) passes through the rotating shaft (2), with its far end connected to the imaging component (7) and its proximal end used to connect to an external host.

13. The rotary cutting device according to claim 1, characterized in that: The rotary cutting drive assembly includes a drive motor and a drive wheel (65) connected to and coaxial with the output shaft of the drive motor, the drive wheel (65) meshing with the outer side of the proximal end of the rotating shaft (2); or, The rotary cutting drive assembly includes a drive motor and a transmission mechanism connected between the output shaft of the drive motor and the rotating shaft (2). The transmission mechanism, the rotating shaft (2), and the output shaft of the drive motor are coaxial.

14. An intravascular rotary cutting device, comprising a sheath (1), a rotating shaft (2) disposed within the sheath (1), a blade assembly (3) connected to the distal end of the rotating shaft (2), and a handle (6) connected to the proximal end of the sheath (1), the handle (6) comprising a housing (61) and a rotary cutting drive assembly configured to drive the rotating shaft (2) to rotate about its own axis, characterized in that: The rotating shaft (2) is detachably connected to the housing (61) and can drive the blade assembly (3) to move out of the channel formed by the sheath (1) and the housing (61) when an external force is applied.

15. The rotary cutting device according to claim 14, characterized in that: The near end of the rotating shaft (2) is provided with a protrusion (222), and the housing (61) has an annular recess that cooperates with the protrusion (222). The far end of the protrusion (222) and / or the annular recess is provided with a guide slope.

16. The rotary cutting device according to claim 15, characterized in that: The protrusion (222) is a series of parallel keys or annular protrusions.

17. The rotary cutting device according to claim 14, characterized in that: The rotary cutting drive assembly includes a drive motor and a drive wheel (65) connected to and coaxial with the output shaft of the drive motor, the drive wheel (65) meshing with the outer side of the proximal end of the rotating shaft (2); or, The rotary cutting drive assembly includes a drive motor and a transmission mechanism connected between the output shaft of the drive motor and the rotating shaft (2). The transmission mechanism, the rotating shaft (2), and the output shaft of the drive motor are coaxial.

18. The rotary cutting device according to claim 14, characterized in that: The rotary cutting device also includes an imaging component (7) and a connecting line (71). The imaging component (7) is located at the far end of the rotating shaft (2) and on the cutter head assembly (3). The connecting line (71) passes through the rotating shaft (2), with its far end connected to the imaging component (7) and its proximal end used to connect to an external host.

Images