Atherectomy device including cutting blades with different edge shapes

Abstract

A plaque removal device includes an outer sheath and a drive shaft. The drive shaft is disposed in the outer sheath and can rotate relative to the outer sheath. The plaque removal device also includes a cutter assembly, which includes a housing connected to the outer sheath and extending distally from the outer sheath. The cutter assembly also includes a proximal cutting element rotatably carried by the housing. The proximal cutting element is connected to the drive shaft and extends distally from the drive shaft, and the proximal cutting element includes at least one proximal cutting blade. The cutter assembly also includes a distal cutting element, which can rotate relative to the housing together with the proximal cutting element. The distal cutting element includes a first distal cutting blade having a first cutting edge and a second distal cutting blade having a second cutting edge. The first cutting edge and the second cutting edge have different shapes.

Description

Technical Field

[0001] The devices and methods described herein generally relate to the treatment of occluded body lumens, such as the removal of occlusive material from a blood vessel or other body site. Background Art

[0002] Peripheral and interventional cardiology is a medical specialty that deals with the treatment of various forms of cardiovascular disease, including coronary artery disease and peripheral vascular disease. Coronary artery disease and peripheral vascular disease can develop as a result of narrowing of the arteries caused by atherosclerosis (also known as hardening of the arteries). Coronary artery disease generally affects the arteries of the heart - the arteries that carry blood to the heart muscle and surrounding tissues. Peripheral vascular disease refers to various diseases of the vascular system outside the heart and brain (for example, which carries blood to the legs).

[0003] Atherosclerosis usually affects medium and large arteries and occurs when fat, cholesterol, and other substances build up on the artery walls and form fleshy or hard / calcified structures called plaques / lesions. When plaque builds up in the artery wall, the artery may narrow and become less flexible, which can make it more difficult for blood to flow through. In peripheral arteries, plaques are usually not localized but may extend along the axis of the artery by as much as 10 millimeters or more (and in some cases up to 400 millimeters or more).

[0004] Pieces of plaque may break off and travel through the affected artery to smaller blood vessels, where they may block smaller blood vessels in some cases and may cause tissue damage or tissue death (embolism). In some cases, atherosclerotic plaque may be associated with weakening of the wall of the affected artery, which may lead to an aneurysm. Minimally invasive surgery may be performed to remove plaque from the arteries in an effort to relieve or help avoid complications of atherosclerosis.

[0005] Some interventional surgical methods can be used to treat atherosclerosis. For example, in balloon angioplasty, a doctor can advance a deflated intravascular balloon catheter into a narrowed artery and can inflate the balloon to crush and / or displace the plaque against the vessel wall. A successful angioplasty can help reopen the artery and allow improved blood flow. Typically, balloon angioplasty is performed in conjunction with the placement of a stent or stent structure within the artery to help minimize restenosis of the artery. However, balloon angioplasty may stretch the artery and induce the formation of scar tissue, while stent placement may cut arterial tissue and also induce the formation of scar tissue. The formation of scar tissue may lead to restenosis of the artery. In some cases, balloon angioplasty may also tear the vessel wall.

[0006] Atherectomy is another treatment for atherosclerosis and involves the use of an intravascular device to mechanically remove (i.e., debulk) plaque from the artery wall. An atherectomy device can allow plaque to be removed from the artery wall, thereby reducing the risk of stretching, cutting, or dissecting the artery wall and causing tissue damage that can lead to restenosis. In some cases, atherectomy can be used to treat restenosis by removing scar tissue.

[0007] Unfortunately, some atherectomy devices are limited in structure and performance. For example, the cutting elements or components of some atherectomy devices cannot effectively treat occlusions that include a heterogeneous mixture of materials (e.g., calcium, plaque, collagen, fibrin, etc.). Therefore, it is desirable to provide improved atherectomy devices and methods. Summary of the invention

[0008] The present disclosure proposes a plaque removal device. The plaque removal device includes a handle configured to be manipulated by a user. A catheter is connected to the handle and the catheter includes an outer sheath and a drive shaft. The drive shaft is disposed in the outer sheath and can rotate relative to the outer sheath. The plaque removal device also includes a cutter assembly, which includes a housing, which is connected to the outer sheath and extends distally from the outer sheath. The cutter assembly also includes a proximal cutting element, which is rotatably carried by the housing. The proximal cutting element is connected to the drive shaft and extends distally from the drive shaft, and the proximal cutting element includes at least one proximal cutting blade. The cutter assembly also includes a distal cutting element, which can rotate relative to the housing together with the proximal cutting element. The distal cutting element includes a first distal cutting blade having a first cutting edge, and the first cutting edge has a first shape. The distal cutting element also includes a second distal cutting blade having a second cutting edge, and the second cutting edge has a second shape different from the first shape.

[0009] A plaque removal device according to the preceding paragraphs, wherein the first cutting edge includes a first proximal portion and a first distal portion, and the second cutting edge includes a second proximal portion and a second distal portion, the second proximal portion being radially disposed inwardly relative to the first proximal portion, and the second distal portion being radially disposed outwardly relative to the first distal portion.

[0010] An atherectomy device as described in any of the preceding paragraphs, wherein the first shape is a smooth curve.

[0011] An atherectomy device according to any of the preceding paragraphs, wherein the first shape and the second shape are smooth curves.

[0012] The atherectomy device of any of the preceding paragraphs, wherein the distal cutting element further comprises a third distal cutting blade having a third cutting edge.

[0013] An atherectomy device as described in any of the preceding paragraphs, wherein the third cutting edge has a third shape, the third shape being different from the first shape and the second shape.

[0014] A plaque removal device according to any of the preceding paragraphs, wherein the first cutting edge includes a first proximal portion and a first distal portion, the second cutting edge includes a second proximal portion and a second distal portion, the third cutting edge includes a third proximal portion and a third distal portion, the first proximal portion is radially arranged outward relative to the second proximal portion and the third proximal portion, and the second distal portion is radially arranged outward relative to the first distal portion and the third distal portion.

[0015] An arteriotomy device according to any of the preceding paragraphs, wherein the first cutting edge further comprises a first intermediate portion disposed between the first proximal portion and the first distal portion, the second cutting edge comprises a second intermediate portion disposed between the second proximal portion and the second distal portion, and the third cutting edge comprises a third intermediate portion disposed between the third proximal portion and the third distal portion, the third intermediate portion being disposed radially outward relative to the first intermediate portion and the second intermediate portion.

[0016] The plaque removal device described in any of the preceding paragraphs, wherein the first shape, the second shape and the third shape are smooth curves.

[0017] An atherectomy device according to any of the preceding paragraphs, wherein the distal cutting element comprises a first number of distal cutting blades, the proximal cutting element comprises a second number of proximal cutting blades, and the second number is twice the first number.

[0018] The present disclosure also proposes a plaque removal device. The plaque removal device includes a handle configured to be manipulated by a user. The catheter is connected to the handle and the catheter includes an outer sheath and a drive shaft. The drive shaft is disposed in the outer sheath and can rotate relative to the outer sheath. The plaque removal device also includes a cutter assembly, which includes a housing, which is connected to the outer sheath and extends distally from the outer sheath. The cutter assembly also includes a first cutting blade, which can rotate relative to the housing. The first cutting blade has a first cutting edge, and the first cutting edge has a first shape. The cutter assembly also includes a second cutting blade, which can rotate relative to the housing together with the first cutting blade. The second cutting blade has a second cutting edge, and the second cutting edge has a second shape different from the first shape. The cutter assembly also includes a third cutting blade, which can rotate relative to the housing together with the first cutting blade and the second cutting blade. The third cutting blade has a third cutting edge, and the third cutting edge has a third shape different from the first shape and the second shape.

[0019] A plaque removal device according to the preceding paragraphs, wherein the first cutting edge includes a first proximal portion and a first distal portion, and the second cutting edge includes a second proximal portion and a second distal portion, the second proximal portion being radially disposed inwardly relative to the first proximal portion, and the second distal portion being radially disposed outwardly relative to the first distal portion.

[0020] A plaque removal device according to any of the preceding paragraphs, wherein the first cutting edge includes a first proximal portion and a first distal portion, the second cutting edge includes a second proximal portion and a second distal portion, the third cutting edge includes a third proximal portion and a third distal portion, the first proximal portion is radially arranged outward relative to the second proximal portion and the third proximal portion, and the second distal portion is radially arranged outward relative to the first distal portion and the third distal portion.

[0021] A plaque removal device according to any of the preceding paragraphs, wherein the first cutting edge also includes a first middle portion disposed between the first proximal portion and the first distal portion, the second cutting edge includes a second middle portion disposed between the second proximal portion and the second distal portion, and the third cutting edge includes a third middle portion disposed between the third proximal portion and the third distal portion, the third middle portion being disposed radially outward relative to the first middle portion and the second middle portion.

[0022] An atherectomy device as described in any of the preceding paragraphs, wherein the first shape is a smooth curve.

[0023] An atherectomy device as described in any of the preceding paragraphs, wherein the first shape and the second shape are smooth curves.

[0024] An atherectomy device as described in any of the preceding paragraphs, wherein the first shape, the second shape, and the third shape are smooth curves.

[0025] The present disclosure also proposes a plaque removal device. The plaque removal device includes a handle configured to be manipulated by a user. A catheter is connected to the handle and the catheter includes an outer sheath and a drive shaft. The drive shaft is disposed in the outer sheath and can rotate relative to the outer sheath. The plaque removal device also includes a cutter assembly, which includes a housing, which is connected to the outer sheath and extends distally from the outer sheath. The cutter assembly also includes a proximal cutting element, which is rotatably carried by the housing. The proximal cutting element is connected to the drive shaft and extends distally from the drive shaft, and the proximal cutting element includes at least one proximal cutting blade. The cutter assembly also includes a distal cutting element, which can rotate relative to the housing together with the proximal cutting element. The distal cutting element includes a first distal cutting blade, which is configured to cut a first contour shape in the occluded material. The distal cutting element also includes a second distal cutting blade, which is configured to cut a second contour shape in the occluded material, and the second contour shape is different from the first contour shape.

[0026] The atherectomy device described in the preceding paragraphs, wherein the distal cutting element further comprises a third distal cutting blade configured to cut a third contour shape in the occlusive material.

[0027] An atherectomy device as described in any of the preceding paragraphs, wherein the third contour shape is different from the first contour shape and the second contour shape.

[0028] The phrases "at least one", "one or more", and "and / or" are open-ended expressions that are both conjunctive and disjunctive in use. For example, each of the expressions "at least one of A, B, and C", "at least one of A, B, or C", "one or more of A, B, and C", "one or more of A, B, or C", and "A, B, and / or C" refers to A alone, B alone, C alone, A and B together, A and C together, B and C together, and A, B, and C together. When each of A, B, and C in the above expressions refers to an element (e.g., X, Y, and Z) or a class of elements (e.g., X1-X n 、Y1-Y m and Z1-Z o ), the phrase is intended to refer to a single element selected from X, Y, and Z, or a combination of elements selected from the same category (e.g., X1 and X2), or a combination of elements selected from two or more categories (e.g., Y1 and Z o ).

[0029] The term "a" or "an" entity refers to one or more of that entity. Therefore, the terms "a" (or "an"), "one or more" and "at least one" can be used interchangeably herein. It should also be noted that the terms "includes," "comprising," and "having" can be used interchangeably. It should also be noted that the terms "includes," "comprising," and "having" can be used interchangeably.

[0030] As used herein, the term "means" should be given the broadest possible interpretation in accordance with 35 U.S.C. Section 112(f). Therefore, a claim containing the term "means" should cover all structures, materials, or actions described herein, and all equivalents thereof. In addition, the structures, materials, or actions and their equivalents should include all contents described in the Summary of the Invention, the Description of the Figures, the Detailed Description, the Abstract, and the Claims.

[0031] It should be understood that each maximum numerical limitation given throughout this disclosure is considered to include each and every lower numerical limitation as an alternative, as if these lower numerical limitations are expressly written herein. Each minimum numerical limitation given throughout this disclosure is considered to include each and every larger numerical limitation as an alternative, as if these larger numerical limitations are expressly written herein. Each numerical range given in this disclosure is considered to include each and every narrower numerical range that falls within the wider numerical range, as if these narrower numerical ranges are expressly written herein.

[0032] The foregoing is a simplified summary of the present disclosure to provide an understanding of some aspects of the present disclosure. The summary is neither a broad nor an exhaustive overview of the present disclosure and its various aspects, embodiments, and configurations. It is neither intended to identify the key or important elements of the present disclosure nor to describe the scope of the present disclosure, but rather to present selected concepts of the present disclosure in a simplified form as an introduction to the more detailed description given below. As will be appreciated, other aspects, embodiments, and configurations of the present disclosure may utilize one or more features described above or described in detail below, alone or in combination. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] The accompanying drawings are incorporated into and form a part of the specification to illustrate several examples of the present disclosure. These drawings, together with the description, explain the principles of the present disclosure. The accompanying drawings simply illustrate preferred and alternative examples of how to make and use the present disclosure, and should not be interpreted as limiting the present disclosure to only the examples shown and described. As shown in the drawings referenced below, other features and advantages will become apparent from the following more detailed description of various aspects, embodiments and configurations of the present disclosure.

[0034] Figure 1 is a side view of a plaque removal system according to an embodiment of the present disclosure.

[0035] Figure 2A yes Figure 1 Detailed side view of the distal portion of the atherectomy system.

[0036] Figure 2B yes Figure 1Detailed perspective view of the distal portion of the atherectomy system.

[0037] Figure 2C yes Figure 2A Detailed transverse cross-sectional view of the distal portion of the atherectomy system.

[0038] Figure 3A yes Figure 1 Perspective view of the distal cutting element of an atherectomy system.

[0039] Figure 3B yes Figure 3A Side view of the distal cutting element.

[0040] Figure 3C is along Figure 3B A cross-sectional view of the distal cutting element taken along line 3C-3C.

[0041] Figure 4 Is Figure 3A Schematic diagram of the cutting profile shape formed by the cutting edge of the distal cutting element.

[0042] Figure 5A yes Figure 1 Perspective view of the proximal cutting element of an atherectomy system.

[0043] Figure 5B yes Figure 5A Front view of the proximal cutting element.

[0044] It should be understood that the drawings are not necessarily drawn to scale. In some cases, details that are not necessary for understanding the present disclosure or that make other details difficult to understand may be omitted. Of course, it should be understood that the present disclosure is not necessarily limited to the specific embodiments shown herein. DETAILED DESCRIPTION

[0045] Before explaining any embodiments of the present disclosure in detail, it should be understood that the application of the present disclosure is not limited to the details of the construction and component arrangement set forth in the following description or shown in the following drawings. The present disclosure is capable of other embodiments and can be practiced or implemented in various ways. In addition, it should be understood that the words and terms used herein are for descriptive purposes and should not be considered limiting. The words "including", "comprising" or "having" and their variations used herein are intended to cover the items listed thereafter and their equivalents as well as additional items.

[0046] The present disclosure generally relates to devices, systems, and methods for mechanical atherectomy. Figure 1, showing an exemplary embodiment of the plaque removal system described herein. The plaque removal system 100 includes an intravascular plaque removal device 102 and a guide wire 104, on which the plaque removal device 102 can be arranged. In some embodiments, the guide wire 104 is silicon-coated or uncoated (bare), or otherwise does not contain a PTFE coating. The plaque removal system according to some embodiments of the present disclosure includes a guide wire 104 including a PTFE coating, or the plaque removal system according to some embodiments of the present disclosure lacks a guide wire 104.

[0047] Continue to refer Figure 1 , the plaque removal device 102 generally includes a handle 106 and a catheter 108. The handle 106 is configured to be grasped and manipulated by a user (e.g., a medical professional) during the plaque removal operation. The catheter 108 is connected to the handle 106 and extends distally relative to the handle 106. The catheter 108 is configured to be positioned in a blood vessel of a subject (e.g., a patient) during the plaque removal operation to facilitate the removal of occlusive materials (e.g., plaque) therefrom. In some embodiments and as shown in the figure, the distal portion 110 of the catheter 108 has an arc shape or configuration. In some embodiments, the distal portion 110 of the catheter 108 normally has an arc configuration ("normally" is understood to mean that the catheter 108 is not subjected to any external contact force due to, for example, contact with the vessel wall), and can be deflected to other configurations. In other embodiments, the distal portion 110 of the catheter 108 normally has a straight shape or configuration, and can be deflected to other configurations. In some embodiments, the catheter 108 can be selectively rotated about a catheter rotation axis 112 relative to the handle 106 to facilitate proper positioning and / or "sweeping" of the distal portion 110 of the catheter 108 during the plaque removal operation. In some embodiments and as shown, the handle 106 carries a rotatable knob or dial 114 for selectively rotating the catheter 108 relative to the handle 106. The catheter 108 includes an outer sheath 116, which is coupled to a cutter assembly 118, which extends distally from the outer sheath 116. The cutter assembly 118 will be described in further detail below.

[0048] Figure 2A-2C The distal portion 110 of the catheter 108 is shown, which includes, among other components, an outer sheath 116 and a cutter assembly 118. The cutter assembly 118 includes a collar 200 that is coupled to the outer sheath 116 and extends distally from the outer sheath. The cutter assembly 118 also includes a housing 202 that is coupled to the collar 200 and extends distally from the collar. The housing 202 rotatably carries a cutting element. Specific reference Figure 2B-2C, the housing 202 rotatably carries a first or distal cutting element 204 and a second or proximal cutting element 206. Rotation of the first and second cutting elements 204, 206 relative to the housing 202 in a rotational direction 210 about a rotational axis 208 causes the cutting elements 204, 206 to cut occlusive material and transport the occlusive material into the housing 202 (a process also referred to as "debulking").

[0049] Still reference Figure 2B-2C , the first cutting element 204 generally extends distally from the second cutting element 206 and the housing 202. The first cutting element 204 includes a central opening 212 (see Figure 2C ) for coupling with the second cutting element 206. The second cutting element 206 is generally disposed within the housing 202, and in some embodiments and as shown, can be completely disposed within the housing 202. The second cutting element 206 is also generally disposed proximal to the first cutting element 204, although the second cutting element 206 includes a shaft or rod 214 that is received in the central opening 212. The rod 214 can be coupled to the first cutting element 204 in a variety of ways. For example, the rod 214 can be coupled to the first cutting element 204 by welding. In some embodiments and as shown, the rod 214 extends distally relative to the first cutting element 204. The rod 214 includes an inner lumen 216 for receiving a guide wire (shown elsewhere).

[0050] Specific reference Figure 2C , the atherectomy device 102 also includes a rotatable drive shaft 218 that couples the first cutting element 204 and the second cutting element 206 to a prime mover (e.g., a motor carried by the handle 106--not shown). That is, the prime mover rotates the drive shaft 218, which in turn rotates the first cutting element 204 and the second cutting element 206 to facilitate cutting of occlusive material and delivery of the occlusive material to the housing 202. In some embodiments, the cutter assembly 118 captures the cut occlusive material from the blood without using vacuum suction. In other embodiments, vacuum suction can help capture the cut occlusive material.

[0051] Continue to refer Figure 2C In some embodiments, the atherectomy device 102 further includes an internal conveyor 220 that is coupled to the drive shaft 218 and rotates with the drive shaft 218. When the occlusive material is delivered into the cutter housing 202 by the first cutting element 204 and the second cutting element 206, the conveyor 220 moves the cut occlusive material proximally through the catheter 108 for discharge to the outside of the subject's body. In some embodiments, this delivery can occur without the assistance of vacuum suction. In other embodiments, vacuum suction can help deliver the cut occlusive material.

[0052] Reference now Figures 3A-3C , the first cutting element 204 includes one or more first or distal cutting grooves or blades, which extend distally relative to the housing 202. In some embodiments and as shown, the first cutting element 204 includes three distal cutting blades 300A, 300B and 300C. In some embodiments, the first cutting element 204 includes different numbers of cutting blades, for example, two, four, five, six, seven, eight, nine, ten or more cutting blades. In some embodiments and as shown, one or more of the distal cutting blades 300A, 300B and 300C extend spirally relative to the rotation axis 208 of the first cutting element 204 and the second cutting element 206.

[0053] Specific reference Figure 3B In some embodiments, the distal cutting blades 300A, 300B, and 300C have a positive lead-in angle 302. That is, the distal cutting blades 300A, 300B, and 300C have a lead-in angle 302 that is measured between (1) an imaginary line 304 extending perpendicularly relative to the rotation axis 208 at the farthest point 306 of the cutting blades 300A, 300B, and 300C and (2) a tangent line 308 tangent to the cutting edges 310A, 310B, and 310C of the cutting blades 300A, 300B, and 300C at the farthest point 306 of the cutting blades 300A, 300B, and 300C. In some embodiments, the lead-in angle 302 is in the range of 15 degrees to 55 degrees. In some embodiments, the lead-in angle 302 is in the range of 25 degrees to 45 degrees. In some embodiments, the lead-in angle 302 is in the range of 30 degrees to 40 degrees. In some embodiments, the lead-in angle 302 is substantially 35 degrees (ie, 35 degrees ± 2.5 degrees).

[0054] Specifically refer to Figure 3CIn some embodiments, the distal cutting blades 300A, 300B, and 300C have a positive rake angle 312. That is, the distal cutting blades 300A, 300B, and 300C have a rake angle 312 measured between an imaginary radius 314 extending from the rotation axis 208 of the first cutting element 204 to the radially farthest edge 316 of the cutting blades 300A, 300B, and 300C and a tangent line 318 tangent to the inner surface 320 of the cutting blades 300A, 300B, and 300C at the radially farthest edge 316. The direction of the rake angle 312 is the same as the rotation direction 210 of the first cutting element 204 and the second cutting element 206 about the rotation axis 208. In some embodiments, the rake angle 312 is in the range of 30 degrees to 80 degrees. In some embodiments, the rake angle 312 is in the range of 35 degrees to 75 degrees. In some embodiments, the rake angle 312 is in the range of 40 degrees to 70 degrees. In some embodiments, the rake angle 312 is in the range of 45 to 65 degrees. In some embodiments, the rake angle 312 is in the range of 50 to 60 degrees. In some embodiments, the rake angle 312 is substantially 55 degrees (ie, 55 ± 2.5 degrees).

[0055] In some embodiments, one or more of the distal cutting blades 300A, 300B and 300C have cutting edges 310A, 310B and 310C with different shapes. These different cutting edges 310A, 310B and 310C are configured to cut different parts of the occlusive material, which is conducive to cutting a relatively small part of the occlusive material compared to the cutting elements with the same shape of cutting edges 310A, 310B and 310C. In some cases, it is relatively effective to cut a relatively small part of the occlusive material, and it is conducive to disposing hard occlusions, such as calcified occlusions. In addition, these different cutting edges 310A, 310B and 310C are conducive to effectively disposing occlusions of heterogeneous mixtures including materials (such as calcified, plaques, collagen, fibrin, etc.).

[0056] Specifically refer to Figure 4 , showing the cutting profile shapes 400A, 400B and 400C formed by the different cutting edges 310A, 310B and 310C of the cutting blades 300A, 300B and 300C, respectively. To illustrate in another way, Figure 4 2 shows the path that each cutting edge 310A, 310B, and 310C intersects with an imaginary transverse plane as the cutting element 204 rotates about the rotation axis 208. To illustrate in yet another way, Figure 4 The edges of the occlusive material cut by the cutting edges 310A, 310B, and 310C are schematically shown from the perspective of a transverse cross-sectional view.

[0057] The following paragraphs describe the specific shapes of cutting edges 310A, 310B and 310C and cutting profile shapes 400A, 400B and 400C. For the sake of brevity, only cutting edges 310A, 310B and 310C are mentioned, but it should be understood that this description is applicable to both cutting edges 310A, 310B and 310C and cutting profile shapes 400A, 400B and 400C. In some embodiments and as shown, each cutting edge 310A, 310B and 310C includes a portion that is further radially outwardly disposed at the same position along the axis of rotation 208 than the portions of other cutting edges 310A, 310B and 310C. More specifically, the first cutting edge 310A includes a first proximal portion 402A, a first middle portion 404A, and a first distal portion 406A, the second cutting edge 310B includes a second proximal portion 402B, a second middle portion 404B, and a second distal portion 406B, and the third cutting edge 310C includes a third proximal portion 402C, a third middle portion 404C, and a third distal portion 406C. The first proximal portion 402A is disposed radially outward relative to the second proximal portion 402B and the third proximal portion 402C, the second distal portion 406B is disposed radially outward relative to the first distal portion 406A and the third distal portion 406C, and the third middle portion 404C is disposed radially outward relative to the first middle portion 404A and the second middle portion 404B.

[0058] In some embodiments and as shown, the cutting edges 310A, 310B, and 310C have a shape that is a smooth curve. That is, the cutting profile shapes 400A, 400B, and 400C have no sharp points.

[0059] In some embodiments, cutting edge 310A, 310B and 310C can have a shape different from the above-mentioned. For example, in some embodiments, one or more of cutting edge 310A, 310B and 310C include a plurality of parts, and the plurality of parts are further radially arranged outwardly at the same axial position than the parts of other cutting edges 310A, 310B and 310C. As another example, in some embodiments, one or more of cutting edge 310A, 310B and 310C have a shape that is not a smooth curve. That is to say, one or more of cutting profile shape 400A, 400B and 400C include one or more sharp points. As another example, in some embodiments, one or more of cutting edge 310A, 310B and 310C include a sawtooth feature and / or a hemispherical pattern, which may be conducive to crushing dense calcareous.

[0060] Reference now Figure 5A-5B, the second cutting element 206 includes one or more second or proximal cutting grooves or blades 500. In some embodiments, the number of blades 500 of the second cutting element 206 is twice that of the first cutting element 204. In some embodiments and as shown, the second cutting element 206 includes six cutting blades 500. In some embodiments and as shown, the proximal cutting blade 500 extends helically relative to the rotation axis 208 of the first cutting element 204 and the second cutting element 206. In some embodiments and with specific reference to Figure 5B , the proximal cutting blade 500 has a negative rake angle 502. Explained in another way, the proximal cutting blade 500 has such a rake angle 502, which is measured between an imaginary radius 504 extending from the rotation axis 208 of the second cutting element to the radially farthest edge 506 of the cutting blade 500 and a tangent 508 tangent to the inner surface 510 of the cutting blade 500 at the radially farthest edge 506. The direction of the rake angle 502 is opposite to the rotation direction 210 of the first cutting element 204 and the second cutting element 206 around the rotation axis 208. Explained in another way, the inner surface 510 of the proximal cutting blade 500 can be tilted outward or forward from the cutting edge. In some embodiments, the rake angle 502 is in the range of 5 degrees to 45 degrees (also referred to as -5 degrees to -45 degrees). In some embodiments, the rake angle 502 is in the range of 6 degrees to 35 degrees (also referred to as -6 degrees to -35 degrees). In some embodiments, the rake angle 502 is in the range of 8 to 24 degrees (also referred to as -8 to -24 degrees). In some embodiments, the rake angle 502 is substantially 16 degrees (ie, 16 degrees ± 2.5 degrees; also referred to as substantially -16 degrees (ie, -16 degrees ± 2.5 degrees)).

[0061] In some embodiments, the positive rake angle 312 of the first cutting element 204 and the negative rake angle 502 of the second cutting element 206 facilitate improving cutting efficiency and / or inhibiting the clogging of occlusive material in the housing 202. More specifically, in some embodiments, the positive rake angle 312 of the first cutting element 204 facilitates cutting and conveying occlusive material toward the second cutting element 206, while the negative rake angle 502 of the second cutting element 206 facilitates moving the occlusive material radially outward and proximally toward the housing 202, thereby inhibiting the clogging of occlusive material in the housing 202.

[0062] In some embodiments and as shown, the cutting rod 214 also includes one or more cutting features 512, which facilitate the fragmentation of occlusive material into small particles to be captured and removed by the plaque removal system 100. In some embodiments and as shown, the cutting rod 214 includes nine cutting features 512. In other embodiments, the cutting rod 214 includes a different number of cutting features 512 (e.g., one, two, three, four, five, six, seven, eight, ten or more cutting features 512). In some embodiments, the cutting feature 512 is a negative feature (e.g., a channel formed on the surface of the cutting rod 214, as shown, or a depression formed on the surface of the cutting rod 214). In some embodiments, the cutting feature 512 is a positive feature (e.g., a ridge or protrusion extending from the surface of the cutting rod 214). In some embodiments and as shown, the cutting feature 512 extends substantially proximally from the leading end 514 of the cutting rod 214. In some embodiments, the cutting feature 512 is configured to be separated from the leading end 514 and / or does not extend proximally along the rod 214.

[0063] The foregoing discussion has been presented for the purpose of illustration and description. The foregoing is not intended to limit the present disclosure to one or more forms disclosed herein. For example, in the preceding summary of the invention, for the purpose of simplifying the present disclosure, various features of the present disclosure are combined together in one or more aspects, embodiments and / or configurations. The features of the aspects, embodiments and / or configurations of the present disclosure may be combined in alternative aspects, embodiments and / or configurations different from those discussed above. This disclosure method should not be interpreted as reflecting the intention that the claims require more features than the features explicitly stated in each claim. On the contrary, as reflected in the following claims, the creative aspects lie in less than all the features of a single aforementioned disclosed aspect, embodiment and / or configuration. Therefore, the following claims are incorporated herein into the specific implementation scheme, and each claim is independent as a separate preferred embodiment of the present disclosure.

[0064] In addition, although the description has included descriptions of one or more aspects, embodiments and / or configurations and certain variations and modifications, other variations, combinations and modifications are also within the scope of the present disclosure, for example, within the skill and knowledge of those skilled in the art after understanding the present disclosure. It is intended to obtain rights including alternative aspects, embodiments and / or configurations within the permitted scope, including alternative, interchangeable and / or equivalent structures, functions, scopes or steps to the claimed protection, regardless of whether such alternative, interchangeable and / or or equivalent structures, functions, scopes or steps are disclosed herein, and it is not intended to publicly dedicate any patentable subject matter.

Claims

1. A plaque removal device, comprising: a handle configured to be manipulated by a user; a catheter coupled to the handle, the catheter comprising an outer sheath and a drive shaft, wherein the drive shaft is disposed within the outer sheath and is rotatable relative to the outer sheath; as well as A cutter assembly comprising: a housing coupled to and extending distally from the outer sheath; a proximal cutting element rotatably carried by the housing, the proximal cutting element being coupled to and extending distally from the drive shaft, the proximal cutting element comprising at least one proximal cutting blade; a distal cutting element rotatable relative to the housing together with the proximal cutting element, the distal cutting element comprising: a first distal cutting blade having a first cutting edge having a first shape; and a second distal cutting blade having a second cutting edge, the second cutting edge having a second shape, the second shape being different from the first shape, Wherein, the first cutting edge includes a first proximal portion and a first distal portion, and the second cutting edge includes a second proximal portion and a second distal portion, the second proximal portion is radially arranged inwardly relative to the first proximal portion, and the second distal portion is radially arranged outwardly relative to the first distal portion.

2. The atherectomy device according to claim 1, wherein: The first shape is a smooth curve.

3. The atherectomy device according to claim 1, wherein: The first shape and the second shape are smooth curves.

4. The atherectomy device according to claim 1, wherein: The distal cutting element also includes a third distal cutting blade having a third cutting edge.

5. The atherectomy device according to claim 4, wherein: The third cutting edge has a third shape that is different from the first shape and the second shape.

6. The atherectomy device according to claim 5, wherein: The third cutting edge includes a third proximal portion and a third distal portion, the first proximal portion being disposed radially outwardly relative to the third proximal portion, and the second distal portion being disposed radially outwardly relative to the third distal portion.

7. The atherectomy device according to claim 6, wherein: The first cutting edge also includes a first intermediate portion disposed between the first proximal portion and the first distal portion, the second cutting edge includes a second intermediate portion disposed between the second proximal portion and the second distal portion, and the third cutting edge includes a third intermediate portion disposed between the third proximal portion and the third distal portion, the third intermediate portion being disposed radially outward relative to the first intermediate portion and the second intermediate portion.

8. The atherectomy device according to claim 7, wherein: The first shape, the second shape, and the third shape are smooth curves.

9. The atherectomy device according to claim 1, wherein: The distal cutting element includes a first number of distal cutting blades, the proximal cutting element includes a second number of proximal cutting blades, and the second number is twice the first number.

10. A plaque removal device, comprising a handle configured to be manipulated by a user; a catheter coupled to the handle, the catheter comprising an outer sheath and a drive shaft, wherein the drive shaft is disposed within the outer sheath and is rotatable relative to the outer sheath; as well as A cutter assembly comprising: a housing coupled to and extending distally from the outer sheath; a distal cutting element rotatably carried by the housing, the distal cutting element comprising: a first cutting blade rotatable relative to the housing, the first cutting blade having a first cutting edge having a first shape; a second cutting blade rotatable relative to the housing together with the first cutting blade, the second cutting blade having a second cutting edge, the second cutting edge having a second shape, the second shape being different from the first shape; and a third cutting blade rotatable relative to the housing together with the first cutting blade and the second cutting blade, the third cutting blade having a third cutting edge, the third cutting edge having a third shape, the third shape being different from the first shape and the second shape, Wherein, the first cutting edge includes a first proximal portion and a first distal portion, and the second cutting edge includes a second proximal portion and a second distal portion, the second proximal portion is radially arranged inwardly relative to the first proximal portion, and the second distal portion is radially arranged outwardly relative to the first distal portion.

11. The atherectomy device according to claim 10, wherein: The third cutting edge includes a third proximal portion and a third distal portion, the first proximal portion being disposed radially outwardly relative to the third proximal portion and the second distal portion being disposed radially outwardly relative to the third distal portion.

12. The atherectomy device according to claim 11, wherein: The first cutting edge also includes a first intermediate portion disposed between the first proximal portion and the first distal portion, the second cutting edge includes a second intermediate portion disposed between the second proximal portion and the second distal portion, and the third cutting edge includes a third intermediate portion disposed between the third proximal portion and the third distal portion, the third intermediate portion being disposed radially outward relative to the first intermediate portion and the second intermediate portion.

13. The atherectomy device according to claim 10, wherein: The first shape is a smooth curve.

14. The atherectomy device according to claim 10, wherein: The first shape and the second shape are smooth curves.

15. The atherectomy device according to claim 10, wherein: The first shape, the second shape, and the third shape are smooth curves.

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