Patent Description:
Peripheral and interventional cardiology is a medical specialty that relates to treatment of various forms of cardiovascular disease, including coronary artery disease and peripheral vascular disease. Coronary artery disease and peripheral vascular disease can arise due to the narrowing of the arteries by atherosclerosis (also called arteriosclerosis). Coronary artery disease generally affects arteries of the heart-arteries that carry blood to cardiac muscles and surrounding tissue. Peripheral vascular disease refers to various diseases of the vascular system outside the heart and brain, which carries blood, for example, to the legs.

Atherosclerosis commonly affects the medium and large arteries, and may occur when fat, cholesterol, and other substances build up on the walls of arteries and form fleshy or hard/calcified structures called plaques/lesions. As plaque forms within an arterial wall, the artery may narrow and become less flexible, which may make it more difficult for blood to flow therethrough. In the peripheral arteries, the plaque is typically not localized, but can extend in length along the axis of the artery for as much as <NUM> or more (in some instance up to <NUM> or more).

Pieces of plaque can break off and move through the affected artery to smaller blood vessels, which may in some instances block them and may result in tissue damage or tissue death (embolization). In some cases, the atherosclerotic plaque may be associated with a weakening of the wall of the affected artery, which can lead to an aneurysm. Minimally invasive surgeries may be performed to remove plaque from arteries in an effort to alleviate or help prevent the complications of atherosclerosis.

A number of interventional surgical methodologies may be used to treat atherosclerosis. In balloon angioplasty, for example, a physician may advance a collapsed, intravascular balloon catheter into a narrowed artery, and may inflate the balloon to macerate and/or displace plaque against the vessel wall. A successful angioplasty may help reopen the artery and allow for improved blood flow. Often, balloon angioplasty is performed in conjunction with the placement of a stent or scaffold structure within the artery to help minimize re-narrowing of the artery. Balloon angioplasty, however, can stretch the artery and induce scar tissue formation, while the placement of a stent can cut arterial tissue and also induce scar tissue formation. Scar tissue formation may lead to restenosis of the artery. In some instances, balloon angioplasty can also rip the vessel wall.

Atherectomy is another treatment methodology for atherosclerosis, and involves the use of an intravascular device to mechanically remove (that is, debulk) plaque from the wall of the artery. Atherectomy devices may allow for the removal of plaque from the wall of an artery, reducing the risk of stretching, cutter, or dissecting the arterial wall and causing tissue damage that leads to restenosis. In some instances, atherectomy may be used to treat restenosis by removing scar tissue.

Some atherectomy devices suffer from structural and performance limitations. For example, atherectomy devices with rotating burrs (for example, the Diamondback <NUM>® PAD System, from Cardiovascular Systems, Inc. ) generally are not configured to capture particles that are released as the burr grinds/sands tissue, which may result in diminished downstream blood flow resulting from particle residue. Additionally, these rotating burrs may cause hemolysis, and are generally limited as an adjunct therapy to angioplasty.

Other atherectomy devices, such as the JETSTREAM G3® System, from Pathway Medical Technologies, include expandable cutters with foldable/movable cutter wings and vacuum-driven aspiration supplied via a vacuum pump, which may cause the artery to collapse on to the cutter and perforate the arterial wall. Other atherectomy systems may include a side window eccentric cutter and distal nosecone which receives material from the cutter. Because the nosecone can only hold a limited volume of plaque, a surgeon may need to repeatedly withdraw the cutter and flush plaque and other material from the nosecone.

Some atherectomy devices are reconfigurable to permit cutters to oppose (that is, at least partially face toward) blood vessel walls. Upon sweeping the cutter within a blood vessel, the cutter can treat a relatively large area of plaque and thereby provide relatively high luminal gain. However, such atherectomy devices are typically relatively complex due to the presence of actuation mechanisms for reconfiguring the devices (for example, one or more pull wires), and such devices are difficult to manufacture in relatively small sizes.

<CIT> relates to apparatus for cutting and removing occlusive material with imaging capabilities. The atherectomy apparatus comprises a first catheter, a second catheter, and a cutter assembly attached to the first catheter. The first catheter is moveable relative to the second catheter to move a distal portion of the atherectomy apparatus between an undeflected configuration and a deflected configuration, wherein the deflected distal portion comprises a double curve having a first proximal curve and a second distal curve.

<CIT> relates to a tissue removal kit or assembly, which comprises a cannula and a tissue removal probe axially slidable within the cannula.

<CIT> relates to an atherectomy device having the ability to create variably sized lumens in a vessel.

Accordingly, it is desirable to provide improved atherectomy devices.

The present disclosure presents an atherectomy device that includes a handle configured to be manipulated by a user. The atherectomy device further includes a catheter, and the catheter includes an outer sheath. The outer sheath includes a proximal portion coupled to and extending distally relative to the handle, and the proximal portion defines a longitudinal axis of the catheter. The outer sheath also includes a distal portion coupled to and extending distally relative to the proximal portion, and the distal portion normally has a curved configuration and is offset from the longitudinal axis. The distal portion comprises a pattern of slits and non-slit portions or a pattern of kerfs and non-kerf portions. The catheter further includes a drive shaft carried within and rotatable relative to the outer sheath. The catheter further includes a cutter assembly coupled to and extending distally relative to the distal portion of the outer sheath. The cutter assembly includes a cutter that is translatably fixed relative to the outer sheath. The cutter is coupled to the drive shaft and rotates about a cutter rotation axis upon rotation of the drive shaft relative to the outer sheath. The cutter rotation axis is normally disposed at an acute angle relative to the longitudinal axis.

The curved configuration includes a proximal curve and distal curve, wherein the proximal curve bends away from the longitudinal axis and the distal curve bends toward the longitudinal axis.

The catheter may be rotatable about a catheter rotation axis relative to the handle.

The catheter rotation axis may be collinear with the longitudinal axis.

The pattern may be a first pattern, the proximal portion comprises a second pattern of slits and non-slit portions, and the second pattern is different than the first pattern.

The acute angle may be about <NUM> degrees.

When each one of A, B, and C in the above expressions refers to an element, such as X, Y, and Z, or class of elements, such as X<NUM>-Xn, Y<NUM>-Ym, and Z<NUM>-Zo, the phrase is intended to refer to a single element selected from X, Y, and Z, a combination of elements selected from the same class (for example, X<NUM> and X<NUM>) as well as a combination of elements selected from two or more classes (for example, Y<NUM> and Zo).

As such, the terms "a" (or "an"), "one or more" and "at least one" may be used interchangeably herein. It is also to be noted that the terms "comprising", "including", and "having" may be used interchangeably.

It should be understood that every maximum numerical limitation given throughout this disclosure is deemed to include each and every lower numerical limitation as an alternative, as if such lower numerical limitations were expressly written herein. Every minimum numerical limitation given throughout this disclosure is deemed to include each and every higher numerical limitation as an alternative, as if such higher numerical limitations were expressly written herein. Every numerical range given throughout this disclosure is deemed to include each and every narrower numerical range that falls within such broader numerical range, as if such narrower numerical ranges were all expressly written herein.

The drawings simply illustrate preferred and alternative examples of how the disclosure may be made and used and are not to be construed as limiting the disclosure to only the illustrated and described examples.

In certain instances, details that are not necessary for an understanding of the disclosure or that render other details difficult to perceive may have been omitted. It should be understood, of course, that the disclosure is not necessarily limited to the particular embodiments illustrated herein.

Before any embodiments of the disclosure are explained in detail, it is to be understood that the disclosure is not limited in its application to the details of construction and the arrangement of components set forth in the following description or illustrated in the following drawings.

The present disclosure relates generally to devices, systems, and methods for mechanical atherectomy. Referring to <FIG>, there is shown an exemplary embodiment of the atherectomy systems described here. The atherectomy system <NUM> includes an intravascular atherectomy device <NUM> and a guide wire <NUM> over which the atherectomy device <NUM> may be deployed. In some embodiments, the guide wire <NUM> is silicon-coated or non-coated (bare), or otherwise free of a PTFE coating. Atherectomy systems according to some embodiments of the present disclosure comprise a guide wire that includes a PTFE coating, or atherectomy systems according to some embodiments of the present disclosure lack a guide wire.

With continued reference to <FIG>, the atherectomy device <NUM> generally includes a handle <NUM> and a catheter <NUM>. The handle <NUM> is configured to be grasped and manipulated by a user (for example, a medical professional) during an atherectomy procedure. The catheter <NUM> is coupled to and extends distally relative to the handle <NUM>. The catheter <NUM> is configured to be positioned in the vasculature of a subject (for example, a patient) during an atherectomy procedure to facilitate removal of plaque therefrom. In some embodiments, the catheter <NUM> is selectively rotatable about a catheter rotation axis <NUM> relative to the handle <NUM> to facilitate appropriately positioning and or "sweeping" a distal portion <NUM> of the catheter <NUM> during an atherectomy procedure. In some embodiments and as illustrated, the handle <NUM> carries a rotatable knob or dial <NUM> for selectively rotating the catheter <NUM> relative to the handle <NUM>.

With further reference to <FIG>, the catheter <NUM> includes an outer sheath <NUM> having a proximal portion <NUM> and a distal portion <NUM>. The proximal portion <NUM> is coupled to and extends distally relative to the handle <NUM>. The proximal portion <NUM> is an elongated component and defines a longitudinal axis <NUM> of the catheter <NUM>. In some embodiments and as illustrated, the longitudinal axis <NUM> is collinear with a catheter rotation axis <NUM>. In other embodiments, the longitudinal axis <NUM> is non-collinear with a catheter rotation axis <NUM>. In some embodiments, the distal portion <NUM> mechanically couples to the proximal portion <NUM> (for example, via welding or the like). In other embodiments, the distal portion <NUM> integrally couples to, or is monolithically formed with, the proximal portion <NUM>. The distal portion <NUM> extends distally relative to the proximal portion <NUM> and, as described in further detail below, normally has a curved configuration and is offset from the longitudinal axis <NUM>. The catheter <NUM> further includes a cutter assembly <NUM> that is coupled to and extends distally relative to the distal portion <NUM> of the outer sheath <NUM>.

<FIG> illustrate the distal portion <NUM> of the catheter <NUM>. The distal portion <NUM> of the outer sheath <NUM> is pre-shaped in a curved configuration or normally has a curved configuration ("normally" being understood as the catheter <NUM> not being subjected to any external contact forces due to, for example, contact with blood vessel walls) and is offset from the longitudinal axis <NUM>. In some embodiments and as illustrated, the curved configuration of the distal portion <NUM> includes a double curve having a first, or proximal curve <NUM> and a second, or distal, curve <NUM>. The proximal curve <NUM> bends or faces away from the longitudinal axis <NUM> and the distal curve <NUM> bends or faces toward the longitudinal axis <NUM>. In some embodiments, the curved configuration causes a rotation axis <NUM> of the cutter assembly <NUM> to be disposed at an acute angle <NUM> relative to the longitudinal axis <NUM> (for example, about <NUM> degrees, although other angles may alternatively be used, such as greater than zero and less than <NUM> degrees, more particularly about <NUM> degrees, <NUM> degrees, <NUM> degrees, <NUM> degrees, <NUM> degrees, <NUM> degrees, <NUM> degrees, <NUM> degrees, <NUM> degrees, <NUM> degrees, <NUM> degrees, <NUM> degrees, <NUM> degrees, <NUM> degrees, <NUM> degrees, <NUM> degrees, or <NUM> degrees) (as used herein regarding angles, the term "about" being understood as the specified angle ± <NUM> percent). In some embodiments and situations, such dispositions of the cutter rotation axis <NUM> relative to the longitudinal axis <NUM> permit the cutter assembly <NUM> to oppose (that is, at least partially face toward) a blood vessel wall. Accordingly, the cutter assembly <NUM> can treat relatively large areas of plaque and provide relatively high luminal gain upon rotating the catheter <NUM> about the catheter rotation axis <NUM>. Further, in some embodiments and situations, the double curve provides the catheter <NUM> with three contact points against the vasculature of the subject. More specifically, the proximal curve <NUM>, the distal curve <NUM>, and the cutter assembly <NUM> may each contact the vasculature of the subject.

Referring specifically to <FIG>, a transverse sectional view of the distal portion <NUM> of the catheter <NUM> is provided. As illustrated, the outer sheath <NUM> carries a rotatable drive shaft <NUM> that couples the cutter assembly <NUM> to a prime mover (for example, a motor carried by the handle <NUM> - not shown). More specifically, the prime mover may rotate the drive shaft <NUM>, which may in turn rotate a cutter <NUM> of the cutter assembly <NUM> with a cutter housing <NUM> of the cutter assembly <NUM> and about the cutter rotation axis <NUM>. Rotation of the cutter <NUM> of causes one or more cutter elements <NUM> (for example, blades) to cut occlusive material and convey the occlusive material into the cutter housing <NUM> (a process also referred to as "debulking"). The drive shaft <NUM> also translatably fixes the cutter <NUM> relative to the outer sheath <NUM>. In some embodiments, the cutter assembly <NUM> captures the cut occlusive material from the blood without the use of vacuum aspiration. In other embodiments, vacuum aspiration may assist capture of the cut occlusive material.

With continued reference to <FIG>, in some embodiments the atherectomy device <NUM> also includes an internal conveyor <NUM> that is coupled to and rotates with the drive shaft <NUM>. As occlusive material is conveyed into the cutter housing <NUM> by the cutter <NUM>, the conveyor <NUM> displaces the cut occlusive material proximally through the catheter <NUM> for discharge outside the subject's body. In some embodiments, this conveyance may occur without the use of vacuum aspiration assistance. In other embodiments, vacuum aspiration may assist conveyance of the cut occlusive material.

<FIG> illustrate the distal portion <NUM> of the outer sheath <NUM> of the catheter <NUM>. In <FIG>, the distal portion <NUM> of the outer sheath <NUM> is illustrated in its normal curved configuration, and in <FIG>, the distal portion <NUM> of the outer sheath <NUM> is illustrated in a deflected configuration. In some embodiments, the distal portion <NUM> comprises one or more materials that are appropriate for being disposed within the vasculature of a subject, such as electropolished nitinol or polyether ether ketone (PEEK). In some embodiments, such materials and others may be set in, or urged to normally occupy, a curved configuration by constraining them in the curved configuration and applying thermal and/or electrical energy. In some embodiments, the distal portion <NUM> has an outer diameter of about <NUM> inches (that is, <NUM> inches ± <NUM> inches) [about <NUM> (that is, <NUM> ± <NUM>)] and an inner diameter of about <NUM> inches (that is, <NUM> inches ± <NUM> inches) [about <NUM> (that is, <NUM> ± <NUM>)].

In some embodiments and as illustrated in <FIG>, in the normal configuration the distal portion <NUM> of the outer sheath <NUM> has a length (that is, a distance between a proximal end <NUM> and a distal end <NUM>, or a distance along the longitudinal axis <NUM> of the catheter <NUM>) of about <NUM> inches (that is, <NUM> inches ± <NUM> inches) [about <NUM> (that is, <NUM> ± <NUM>)]. In some embodiments and as illustrated in <FIG>, in the normal configuration the distal portion <NUM> of the outer sheath <NUM> has an offset dimension or a span (that is, a distance between the proximal end <NUM> and the distal end <NUM> and the second curve <NUM>, or a distance perpendicular to the longitudinal axis <NUM> of the catheter <NUM>) of about <NUM> inches (that is, <NUM> inches ± <NUM> inches) [about <NUM> (that is, <NUM> ± <NUM>)].

With continued reference to <FIG>, the distal portion <NUM> includes a distal section <NUM>, an intermediate section <NUM> (which defines the second curve <NUM> described above), and a proximal section <NUM> (which defines the first curve <NUM> described above). The distal section <NUM>, the intermediate section <NUM>, and the proximal section <NUM> may have about the dimensions shown in Table <NUM> (angles are relative to the longitudinal axis <NUM> of the catheter <NUM>, distances are projected onto the longitudinal axis <NUM> of the catheter <NUM> - "about" being understood as the specified dimension ± <NUM> percent, and the term "substantially" being understood as the specified dimension ± percent).

The distal portion <NUM> of the outer sheath <NUM> may be relatively stiff to permit the catheter <NUM> to remove plaque from the vasculature in a curved configuration of the distal portion <NUM>, and the distal portion <NUM> may be sufficiently flexible to deflect (for example and as shown in <FIG>, to a relatively straight configuration) while navigating the vasculature of a subject. To provide flexibility, in some embodiments the distal portion <NUM> includes a plurality of slits or kerfs <NUM> (that is, absences of material) that each extend through the wall of the distal portion <NUM>. Such kerfs <NUM> may be provided by, for example, laser cutting processes. In some embodiments and as illustrated in <FIG>, the distal portion <NUM> includes first pattern of alternating kerfs <NUM> and non-slit or non-kerf portions <NUM> (that is, portions of the distal portion <NUM> include material and lacking kerfs <NUM>) over its length. For example, the pattern of alternating kerfs <NUM> and non-kerf portions <NUM> may include, at each axial position within the pattern, a first kerf <NUM> having a longitudinal width of about <NUM> inches [<NUM>] and a circumferential length of about <NUM> degrees, a first non-kerf portion <NUM> having a circumferential length of about <NUM> degrees, a second kerf <NUM> having a longitudinal width of about <NUM> inches [<NUM>] and a circumferential length of about <NUM> degrees, a second non-kerf portion <NUM> having a circumferential length of about <NUM> degrees, a third kerf <NUM> having a longitudinal width of about <NUM> inches [<NUM>] and a circumferential length of about <NUM> degrees, and a third non-kerf portion <NUM> having a circumferential length of about <NUM> degrees (as used herein regarding kerf, non-kerf portion, and pattern dimensions, the term "about" being understood as the specified dimension ± <NUM> percent). Sets of kerfs <NUM> and non-kerf portions <NUM> in each axial position may be offset from sets of kerfs <NUM> and non-kerf portions <NUM> at one or more adjacent axial positions by (that is, the pattern may have a pitch of) about <NUM> inches [<NUM>]. As illustrated, the pitch may be constant along the length of the outer sheath <NUM>. In other embodiments, the pitch may be variable. As illustrated, the kerfs <NUM> may be perpendicular to the longitudinal axis (that is, the pattern may have a pitch angle of zero degrees). In other embodiments, the kerfs <NUM> may be non-perpendicular to the longitudinal axis (that is, the pattern may have a non-zero pitch angle). In some embodiments, the pattern may have a variable pitch angle.

<FIG> illustrate the proximal portion <NUM> of the outer sheath <NUM> of the catheter <NUM>. In some embodiments, the proximal portion <NUM> comprises one or more materials that are appropriate for being disposed within the vasculature of a subject, such as tempered stainless steel. In some embodiments, the proximal portion <NUM> has an outer diameter of about <NUM> inches (that is, <NUM> inches ± <NUM> inches) [about <NUM> (that is, <NUM> ± <NUM>)] and an inner diameter of about <NUM> inches (that is, <NUM> inches ± <NUM> inches) [about <NUM> (that is, <NUM> ± <NUM>)].

In some embodiments and as illustrated, the proximal portion <NUM> of the outer sheath <NUM> includes several sections having different flexibility characteristics. Generally, the proximal portion <NUM> is relatively stiff near its proximal end <NUM> to facilitate pushability of the catheter <NUM>, and the proximal portion <NUM> is relatively flexible near its distal end <NUM> to facilitate navigating the vasculature of a subject. More specifically, the proximal portion <NUM> includes a relatively stiff proximal end section <NUM>. In contrast to other sections, as described below, the proximal end section <NUM> lacks slits or kerfs. The proximal end section <NUM> may have a length of about <NUM> inches (that is, <NUM> inches ± <NUM> inches) [about <NUM> (that is, <NUM> ± <NUM>)].

The proximal portion <NUM> also includes a first intermediate section <NUM> that extends distally relative to the proximal end section <NUM>. The first intermediate section <NUM> may have a length of about <NUM> inches (that is, <NUM> inches ± <NUM> inches) [about <NUM> (that is, <NUM> ± <NUM>)]. The first intermediate section <NUM> may be relatively stiff compared to other sections. More specifically, the first intermediate section <NUM> may include a second pattern of kerfs and non-kerf portions (not shown) over its length. For example, the pattern of alternating kerfs and non-kerf portions may include, at each axial position within the pattern, a first kerf having a longitudinal width of about <NUM> inches [about <NUM>] and a circumferential length of about <NUM> degrees, a first non-kerf portion having a circumferential length of about <NUM> degrees, a second kerf having a longitudinal width of about <NUM> inches [about <NUM>] and a circumferential length of about <NUM> degrees, a second non-kerf portion having a circumferential length of about <NUM> degrees, a third kerf having a longitudinal width of about <NUM> inches [about <NUM>] and a circumferential length of about <NUM> degrees, a third non-kerf portion having a circumferential length of about <NUM> degrees, a fourth kerf having a longitudinal width of about <NUM> inches [about <NUM>] and a circumferential length of about <NUM> degrees, and a fourth non-kerf portion having a circumferential length of about <NUM> degrees. Sets of kerfs and non-kerf portions in each axial position may be offset from sets of kerfs and non-kerfs portions at one or more adjacent axial positions by (that is, the pattern may have a pitch of) about <NUM> inches (that is, <NUM> inches ± <NUM> inches) [about <NUM> (that is, <NUM> ± <NUM>)]. The pitch may be constant or variable. The kerfs may be perpendicular to the longitudinal axis or non-perpendicular to the longitudinal axis. The pattern may have a variable pitch angle.

The proximal portion <NUM> also includes a second intermediate section <NUM> that extends distally relative to the first intermediate section <NUM>. The second intermediate section <NUM> may have a length of about <NUM> inches (that is, <NUM> inches ± <NUM> inches) [about <NUM> (that is, <NUM> ± <NUM>)]. The second intermediate section <NUM> may be relatively flexible compared to the first intermediate section <NUM>. More specifically, the second intermediate section <NUM> may include a third pattern of kerfs and non-kerf portions (not shown) over its length. For example, the pattern of alternating kerfs and non-kerf portions may include, at each axial position within the pattern, a first kerf having a longitudinal width of about <NUM> inches [about <NUM>] and a circumferential length of about <NUM> degrees, a first non-kerf portion having a circumferential length of about <NUM> degrees, a second kerf having a longitudinal width of about <NUM> inches [about <NUM>] and a circumferential length of about <NUM> degrees, a second non-kerf portion having a circumferential length of about <NUM> degrees, a third kerf having a longitudinal width of about <NUM> inches [about <NUM>] and a circumferential length of about <NUM> degrees, a third non-kerf portion having a circumferential length of about <NUM> degrees, a fourth kerf having a longitudinal width of about <NUM> inches [about <NUM>] and a circumferential length of about <NUM> degrees, and a fourth non-kerf portion having a circumferential length of about <NUM> degrees. Sets of kerfs and non-kerf portions in each axial position may be offset from sets of kerfs and non-kerfs portions at one or more adjacent axial positions by (that is, the pattern may have a pitch of) about <NUM> inches (that is, <NUM> inches ± <NUM> inches) [about <NUM> (that is, <NUM> ± <NUM>)]. The pitch may be constant or variable. The kerfs may be perpendicular to the longitudinal axis or non-perpendicular to the longitudinal axis. The pattern may have a variable pitch angle.

The proximal portion <NUM> also includes a third intermediate section <NUM> that extends distally relative to the second intermediate section <NUM>. The third intermediate section <NUM> may have a length of about <NUM> inches (that is, <NUM> inches ± <NUM> inches) [about <NUM> (that is, <NUM> ± <NUM>)]. The third intermediate section <NUM> may be relatively flexible compared to the second intermediate section <NUM>. More specifically, the third intermediate section <NUM> may include a fourth pattern of kerfs and non-kerf portions (not shown) over its length. For example, the pattern of alternating kerfs and non-kerf portions may include, at each axial position within the pattern, a first kerf having a longitudinal width of about <NUM> inches [about <NUM>] and a circumferential length of about <NUM> degrees, a first non-kerf portion having a circumferential length of about <NUM> degrees, a second kerf having a longitudinal width of about <NUM> inches [about <NUM>] and a circumferential length of about <NUM> degrees, a second non-kerf portion having a circumferential length of about <NUM> degrees, a third kerf having a longitudinal width of about <NUM> inches [about <NUM>] and a circumferential length of about <NUM> degrees, a third non-kerf portion having a circumferential length of about <NUM> degrees, a fourth kerf having a longitudinal width of about.

<NUM> inches [about <NUM>] and a circumferential length of about <NUM> degrees, and a fourth non-kerf portion having a circumferential length of about <NUM> degrees. Sets of kerfs and non-kerf portions in each axial position may be offset from sets of kerfs and non-kerfs portions at one or more adjacent axial positions by (that is, the pattern may have a pitch of) about <NUM> inches (that is, <NUM> inches ± <NUM> inches) [about <NUM> (that is, <NUM> ± <NUM>)]. The pitch may be constant or variable. The kerfs may be perpendicular to the longitudinal axis or non-perpendicular to the longitudinal axis. The pattern may have a variable pitch angle.

The proximal portion <NUM> further includes a relatively stiff distal end section <NUM>. The distal end section <NUM> lacks slits or kerfs. The distal end section <NUM> may have a length of about <NUM> inches (that is, <NUM> inches ± <NUM> inches) [about <NUM> (that is, <NUM> ± <NUM>)].

In some embodiments and as illustrated, the atherectomy system <NUM> lacks any components for actively deflecting or reconfiguring the catheter <NUM> (for example, pull wires for deflecting or reconfiguring the catheter <NUM>). Stated another way, in some embodiments the catheter <NUM> is only passively deflected or reconfigured (that is, reconfiguration or defection caused by external contact forces due to, for example, extending through an introducer sheath and/or contact with blood vessel walls). In some embodiments, the lack of components for actively deflecting or reconfiguring the catheter <NUM> permits the catheter <NUM> to have a relatively small overall size, such as <NUM>-French. In some embodiments, the catheter <NUM> may have other overall sizes, such as <NUM>-French, <NUM>-French. <NUM>-French, or the like.

<FIG> illustrate the catheter <NUM> navigating the vasculature <NUM> of a subject and removing plaque. <FIG> illustrates the catheter <NUM> being passively deflected to a relatively straight configuration while navigating the vasculature <NUM>. As described above, the catheter <NUM> may be passively deflected or reconfigured by extending through an introducer sheath and/or contacting blood vessel walls. <FIG> illustrates the catheter <NUM> occupying a curved configuration and the cutter assembly <NUM> being disposed near plaque <NUM> within the vasculature <NUM>. <FIG> illustrates the catheter <NUM> occupying a curved configuration and the cutter assembly <NUM> removing plaque <NUM> from the vasculature <NUM>. The catheter <NUM> may be rotated about the catheter rotation axis <NUM> (or "swept") to further remove plaque <NUM> and provide relatively high luminal gain.

Although it is not shown in the drawings, when the distal portion <NUM> of the outer sheath <NUM> of the catheter <NUM> is inserted within a lumen of an introducer sheath, passing through the lumen of the introducer sheath, and/or exiting the introducer sheath, the distal portion <NUM> and/or the cutter assembly <NUM> is designed to contact the inner wall of the introducer sheath. That is, the distal portion <NUM> of the outer sheath <NUM> is pre-shaped in a curved configuration or normally has a curved configuration to ensure that the distal portion <NUM> and/or the cutter assembly <NUM> always contacts the inner wall of the introducer sheath as the distal portion <NUM> and/or the cutter assembly <NUM> pass through the lumen formed within the introducer sheath. Similarly, as the distal portion <NUM> and/or the cutter assembly <NUM> exits the introducer sheath, the distal portion <NUM> and/or the cutter assembly <NUM> contacts vasculature <NUM> and/or the plaque <NUM>.

The foregoing discussion has been presented for purposes of illustration and description. The foregoing is not intended to limit the disclosure to the form or forms disclosed herein. In the foregoing Summary for example, various features of the disclosure are grouped together in one or more aspects, embodiments, and/or configurations for the purpose of streamlining the disclosure. The features of the aspects, embodiments, and/or configurations of the disclosure may be combined in alternate aspects, embodiments, and/or configurations other than those discussed above. This method disclosed is not to be interpreted as reflecting an intention that the claims require more features than are expressly recited in each claim. Rather, the scope of the invention is defined by the appended claims.

Claim 1:
An atherectomy device (<NUM>), comprising:
a handle (<NUM>) configured to be manipulated by a user;
a catheter comprising:
an outer sheath (<NUM>) comprising:
a proximal portion (<NUM>) coupled to and extending distally relative to the handle (<NUM>), the proximal portion (<NUM>) defining a longitudinal axis of the catheter;
a distal portion (<NUM>) coupled to and extending distally relative to the proximal portion (<NUM>), the distal portion (<NUM>) normally having a curved configuration and being offset from the longitudinal axis (<NUM>), and the distal portion (<NUM>) comprising a pattern of slits and non-slit portions or a pattern of kerfs and non-kerf portions;
a drive shaft carried within and rotatable relative to the outer sheath (<NUM>); and
a cutter assembly (<NUM>) coupled to and extending distally relative to the distal portion (<NUM>) of the outer sheath (<NUM>), the cutter assembly (<NUM>) including a cutter being translatably fixed relative to the outer sheath (<NUM>), the cutter coupled to the drive shaft and rotated about a cutter rotation axis upon rotation of the drive shaft relative to the outer sheath (<NUM>), the cutter rotation axis normally being disposed at an acute angle (<NUM>) relative to the longitudinal axis (<NUM>);
wherein the curved configuration comprises a proximal curve (<NUM>) and distal curve (<NUM>); and
wherein the proximal curve (<NUM>) bends away from the longitudinal axis (<NUM>) and the distal curve (<NUM>) bends toward the longitudinal axis (<NUM>).