Patent Description:
This application may also be related to International Application No. <CIT>, entitled "ATHERECTOMY CATHETER WITH SHAPEABLE DISTAL TIP," which claims priority to <CIT>, entitled "ATHERECTOMY CATHETER WITH SHAPEABLE DISTAL TIP".

This application may also be related to <CIT>, entitled "OCCLUSION-CROSSING DEVICES," which claims priority to <CIT>, entitled "OCCLUSION-CROSSING DEVICES," and to <CIT>, entitled "OCCLUSION-CROSSING DEVICES".

Described herein are devices for treatment of an occluded body lumen, such as for the removal of occlusive materials from blood vessels. In particular, described herein are atherectomy catheters that are adapted to easily maneuver against tissue and plaque buildup within vessels for debulking.

Atherosclerosis is disease in which accumulation of atheromatous materials builds up inside a person's arteries. Atherosclerosis occurs as part of the natural aging process, but may also occur due to a person's diet, hypertension, vascular injury, heredity, and so forth. Atherosclerosis can affect any artery in the body, including arteries in the heart, brain, arms, legs, pelvis, and kidneys. Atherosclerosis deposits may vary in their properties as well. Some deposits are relatively soft, other types may be fibrous, some are calcified, or a combination of all three. Based on the location of the plaque accumulation, different diseases may develop. For example, coronary heart disease occurs when plaque builds up in the coronary arteries, which supply oxygenated blood to the heart. If plaque buildup blocks the carotid artery, arteries located on each side of the neck that supply oxygen to the brain, a stroke may be the result.

Atherosclerosis may be treated in a number of ways including medication, bypass surgery, and catheter-based approaches. Atherectomy procedures involve excising or dislodging materials that block a blood vessel. Many atherectomy catheters typically have a substantially straight central axis. However, atherectomy catheters having a straight profile may be difficult to maneuver close enough to the inner surface of the arterial walls to remove all plaque buildup. Moreover, plaque removal can be complicated with such straight profile catheters when plaque formations accumulate in the curves and more tortuous portions of an artery.

The atherectomy catheters described herein address some of these challenges.

No surgical methods are claimed.

Described herein are atherectomy catheters for use in vessels. The catheters can include a rotatable cutter within a catheter. The shape of the catheter can be configured to aid optimal positioning of the cutter, for example during a cutting procedure. In some cases, the cutter may be extended through a window of the catheter upon translation of the cutter within the catheter. In some cases, the cutter is retractable into the catheter.

In one embodiment, an atherectomy catheter for use in a vessel includes an elongate catheter body and an annular cutter. The elongate catheter body includes a fixed jog section with a pre-set curvature and a flexible section that has a greater flexibility than a remainder of the elongate catheter body. The fixed jog section and flexible section are formed of a frame including a plurality of circumferential slits therein.

This and other embodiments can include one or more of the following features. The frame in the fixed jog section can further include a longitudinal spine extending therethrough that does not have slits. The atherectomy catheter can further include a cutting window through which the annular cutter extends. The cutting window can be positioned distal of the fixed jog section and the flexible section so as to urge the cutter into the vessel. The atherectomy catheter can further include at least one laminating layer positioned over or under the frame of the fixed jog section. The laminating layer can be made of a polymer. The frame can be made of metal. The plurality of circumferential slits can be arranged in a repeating pattern. The fixed jog section can form an angle of <NUM>° to <NUM>° in the elongate catheter body. The frame can further include an annular spine without slits that extends between the fixed jog section and the flexible section. The flexible section can be configured to passively bend to angles of <NUM>°-<NUM>°.

In general, in one embodiment, an atherectomy catheter for use in a vessel includes an elongate catheter body, an annular cutter, and curved portion in the elongate catheter body. The curved portion can have any of a number of shapes, such as an s-shape. The curved portion includes a frame having a plurality of annular spines connected together by a longitudinal proximal spine and a longitudinal distal spine. The longitudinal proximal spine is positioned approximately <NUM> degrees away from the longitudinal distal spine.

This and other embodiments can include one or more of the following features. The plurality of annular spines can include a first annular spine, a second annular spine, and a third annular spine. The longitudinal proximal spine can connect the first annular spine and the second annular spine, and the longitudinal distal spine can connect the second annular spine and the third annular spine. The atherectomy catheter can further include a cutting window through which the annular cutter extends. The cutting window can be positioned distal of the curved portion and on an outer circumference of the s-shaped curve so as to urge the cutter into the vessel. The s-shaped curved portion can be configured to be activated by pulling or pushing on a shaft of the atherectomy catheter. The atherectomy catheter can further include at least one laminating layer positioned over or under the frame. The laminating layer can be made of a polymer. The frame can be made of metal. The distal longitudinal spine can be positioned adjacent to an exposed portion of the cutter. The distal longitudinal spine can be on a same side of the elongate catheter body as the exposed portion of the cutter. The longitudinal proximal spine can form a first angle, and the longitudinal distal spine can form a second angle. The first and second angles can extend in opposite directions, and the first angle can be between <NUM> and <NUM> degrees and the second angle can be between <NUM> and <NUM> degrees. A distal-most spine of the plurality of spines can include a beveled distal edge. The atherectomy catheter can further include a nosecone configured to pivot away from the elongate body to expose the cutter. The bevel can be configured to provide space for the nosecone to pivot.

In general, in one embodiment, an atherectomy catheter for use in a vessel includes an elongate catheter body, an annular cutter, and an s-shaped curved portion in the elongate catheter body. The curved portion includes a frame having a proximal section and a distal section. The proximal section has a plurality of circumferential proximal slits and a longitudinal proximal spine without slits, and the distal section having a plurality of circumferential distal slits and a longitudinal distal spine without slits. The longitudinal proximal spine is positioned approximately <NUM> degrees away from the longitudinal distal spine.

This and other embodiments can include one or more of the following features. The atherectomy catheter can further include a cutting window through which the annular cutter extends. The cutting window can be positioned distal of the distal section and on an outer circumference of the s-shaped curve so as to urge the cutter into the vessel. The s-shaped curved portion can be configured to be activated by pulling or pushing on a shaft of the atherectomy catheter. The atherectomy catheter can further include at least one laminating layer positioned over or under the frame. The laminating layer can be made of a polymer. The frame can be made of metal. The plurality of circumferential proximal slits can be arranged in a first repeating pattern, and the plurality of circumferential distal slits can be arranged in a second repeating pattern. The first repeating pattern and the second repeating pattern can be circumferentially offset from one another. The distal longitudinal spine can be positioned adjacent to an exposed portion of the cutter. The distal longitudinal spine can be on a same side of the elongate catheter body as the exposed portion of the cutter. The proximal section can form a first angle, and the distal section forms a second angle. The first and second angles can extend in opposite directions, and the first angle can be between <NUM> and <NUM> degrees and the second angle can be between <NUM> and <NUM> degrees. The frame can further include an annular spine without slits extending between the proximal section and the distal section.

In general, in one embodiment, an atherectomy catheter for use in a vessel includes an elongate catheter body, an annular cutter, and an s-shaped curved portion in the elongate catheter body. The curved portion includes a frame having a proximal section and a distal section. The proximal section has a plurality of circumferential proximal slits and a longitudinal proximal spine without slits, and the distal section having a plurality of circumferential distal slits and a longitudinal distal spine without slits. The longitudinal proximal spine is positioned approximately <NUM> degrees away from the longitudinal distal spine, and the circumferential slits are in a tongue and groove formation.

In some examples, an atherectomy device includes: a catheter including a distal nosecone fixedly coupled to a proximal flexible section and a cutter window between the distal nosecone and the proximal flexible section, wherein an extent of curvature of the proximal flexible section is adjustable; and a cutter coupled to a rotatable driveshaft within the catheter, wherein proximal movement of the cutter and the rotatable driveshaft causes the cutter to tilt in a first direction and to extend though the cutter window, wherein distal movement of the cutter and the rotatable driveshaft causes the cutter to tilt in a second direction opposite the first direction and to retract within the catheter. The extent of curvature of the proximal flexible section can be adjustable based on an amount of force applied to the cutter and the rotatable driveshaft in a proximal direction. Initial proximal movement of the cutter and the rotatable driveshaft can cause the cutter to tilt in the first direction and extend through the cutter window, where further proximal movement of the cutter and the rotatable driveshaft can cause the flexible section to bend. Likewise, distal movement of the cutter and the rotatable driveshaft can cause the flexible section to straighten from a bent state. The proximal flexible section can be configured to bend to an s-shape. The proximal flexible section can be configured to bend incrementally based on an amount of compression on the proximal flexible section via proximal movement of the cutter and the rotatable driveshaft. The cutter can include a ledge that is configured to slide along an edge of an inner surface of the catheter to move the cutter radially and extend the cutter through the cutting window. The edge can be sloped with respect to an axis perpendicular to the longitudinal axis of the distal nosecone. The edge can be configured to tilt the cutter with respect to the nosecone when the ledge of the cutter slides along the edge. The edge can be on a bushing of the catheter. The cutter window can be on a side of the catheter.

In some examples, an atherectomy device includes: a catheter including a nosecone fixedly coupled to a elongate body at a fixed bend of the catheter, wherein the catheter includes a cutter window on a convex side of the fixed bend; and a cutter coupled to a rotatable driveshaft within the catheter, wherein proximal movement of the cutter and the rotatable driveshaft causes the cutter to tilt in a first direction and to extend though the cutter window, wherein distal movement of the cutter and the rotatable driveshaft causes the cutter to tilt in a second direction opposite the first direction and to retract within the catheter. The cutting window can be distally located along the catheter with respect to the fixed bend. The cutter can be configured to move radially when extending through the cutting window. At least a portion of a cutting edge of the cutter can correspond to a most prominent point along the convex side of the fixed bend when the cutter is extended through the window. The cutter can be configured to transition between an active mode and a passive mode, wherein a cutting edge of the cutter extends through the window in the active mode, and wherein the cutting edge of the cutter is retracted within the catheter in the passive mode. The cutter can be substantially parallel to the nosecone in the active mode and substantially parallel to the elongate body in the passive mode. The cutting edge of the cutter can be held in the passive mode by a detent that requires a threshold translational force applied to the rotatable driveshaft to release the detent and transition the cutter from the passive mode. The cutter can include an annular groove that provides clearance for an inner surface of the catheter. The cutter can be rotatable when in the active mode and the passive mode. The cutter can include an imaging sensor configured to collect images outside of the catheter while the cutter is in the active mode and the passive mode. The catheter can include one or more openings configured to align with the imaging sensor and act as a location marker for the imaging sensor when the cutter is in the active mode. The fixed bend can have an angle ranging from <NUM> degree to <NUM> degrees. A central axis of the cutter can be at an angle ranging from <NUM> degree to <NUM> degrees with respect to a central axis of the distal nosecone when the cutter is extended through the cutting window. The cutter can include a ledge that is configured to slide along an edge within the lumen of the catheter to move the cutter radially and extend the cutter through the cutting window upon proximal movement of the cutter and the rotatable driveshaft. A lumen of the catheter can define a first channel and a second channel, wherein a sloped edge within the lumen is configured to urge the cutter from the first channel to the second channel upon proximal movement of the cutter and the rotatable driveshaft. The cutter can be configured to move distally to pack tissue into the distal nosecone. The cutter can be configured to transition between being parallel to the nosecone and parallel to the elongate body. The elongate body can include a flexible section proximally located relative to the fixed bend, wherein an extent of curvature of the proximal flexible section is adjustable. The flexible section can be configured to take on an s-shaped curved shape upon further proximal movement of the cutter and rotatable driveshaft within the catheter.

In some examples, an atherectomy device includes: a catheter including a distal nosecone fixedly coupled to a flexible section and a cutter window between the distal nosecone and the flexible section, wherein the flexible section includes a longitudinal spine on a side of the flexible section; and a cutter coupled to a rotatable driveshaft within the catheter, wherein proximal movement of the cutter and the rotatable driveshaft causes the cutter to tilt in a first direction and to extend though the cutter window, wherein a force applied to the rotatable shaft in a proximal direction causes the flexible section to bend away from the longitudinal spine and to take on a curvature, and wherein distal movement of the cutter and the rotatable driveshaft causes the cutter to tilt in a second direction opposite the first direction and to retract within the cutter window. An extent of curvature of the flexible section can be adjustable based on an amount of force applied to the cutter and the rotatable driveshaft in a proximal direction. The proximal flexible section can be configured to bend to an s-shape. The flexible section can be configured to bend incrementally based on an amount of compression on the flexible section via proximal movement of the cutter and the rotatable driveshaft. The cutter can include a ledge that is configured to slide along an edge of an inner surface of the catheter to move the cutter radially and extend the cutter through the cutter window. The edge can be sloped with respect to an axis perpendicular to the longitudinal axis of the distal nosecone. The edge can be configured to tilt the cutter with respect to the nosecone when the ledge of the cutter slides along the edge. The edge can be on a bushing of the catheter. The atherectomy device can further include a handle at a proximal end of the catheter, wherein the handle includes a lock configured to lock the flexible section in a curved shape having a selected extent of curvature. The lock can be configured to allow a user to choose a locked position of the driveshaft with respect to the catheter by <NUM> inches (to be considered for the whole description: <NUM> inch ≈ <NUM>) or less. The lock can include a slider button that is configured to slide distally and proximally. Sliding the slider button proximally can increase the curvature of the flexible section. The slider button can include teeth that are configured to engage with corresponding teeth within the handle to lock an axial position of the driveshaft with respect to the catheter. The handle can include a spring that applies pressure to the slider button to keep the teeth of the slider button engaged with the corresponding teeth within the handle. The slider button can be configured to compress the spring when a user presses on the slider button to disengage the teeth of the slider button from the corresponding teeth within the handle. The handle can include a spine joint that allows axial translation of the slider button with respect to the driveshaft while allowing the driveshaft to rotate with respect to the slider button. The flexible section can include a first portion axially adjacent to a second portion, the first portion having a first longitudinal spine and the second portion having a second longitudinal spine, wherein the first longitudinal spine and second longitudinal spine are on opposing sides of the flexible section, and wherein the force applied to the rotatable shaft in the proximal direction causes the first portion to bend laterally away from the first longitudinal spine and the second portion to bend laterally away from the second longitudinal spine.

In some examples, an atherectomy device includes: a catheter including a nosecone fixedly coupled to an elongate body at a fixed bend of the catheter, wherein the catheter includes a cutter window on a convex side of the fixed bend; and a cutter coupled to a rotatable driveshaft within the catheter, wherein proximal movement of the cutter and the rotatable driveshaft causes the cutter to tilt in a first direction and to extend though the cutter window, wherein distal movement of the cutter and the rotatable driveshaft causes the cutter to tilt in a second direction opposite the first direction and to retract within the catheter. The cutter window can be distally located along the catheter with respect to the fixed bend. The cutter can be configured to move radially when extending through the cutter window. At least a portion of a cutting edge of the cutter can correspond to a most prominent point along the convex side of the fixed bend when the cutter is extended through the cutter window. The cutter can be configured to transition between an active mode and a passive mode, wherein a cutting edge of the cutter extends through the cutter window in the active mode, and wherein the cutting edge of the cutter is retracted within the catheter in the passive mode. The cutter can be substantially parallel to the nosecone in the active mode and substantially parallel to the elongate body in the passive mode. The cutting edge of the cutter can be held in the passive mode by a detent that requires a threshold translational force applied to the rotatable driveshaft to release the detent and transition the cutter from the passive mode. The cutter can be rotatable when in the active mode and the passive mode. The cutter can include an imaging sensor configured to collect images outside of the catheter while the cutter is in the active mode and the passive mode. The catheter can include one or more openings configured to align with the imaging sensor and act as a location marker for the imaging sensor when the cutter is in the active mode. The fixed bend can have an angle ranging from <NUM> degree to <NUM> degrees. A central axis of the cutter is at an angle ranging from <NUM> degree to <NUM> degrees with respect to a central axis of the distal nosecone when the cutter is extended through the cutter window. The cutter can include a ledge that is configured to slide along an edge within the lumen of the catheter to move the cutter radially and extend the cutter through the cutter window upon proximal movement of the cutter and the rotatable driveshaft. A lumen of the catheter defines a first channel and a second channel, wherein a sloped edge within the lumen is configured to urge the cutter from the first channel to the second channel upon proximal movement of the cutter and the rotatable driveshaft. The cutter can be configured to move distally to pack tissue into the distal nosecone. The cutter can be configured to transition between being parallel to the nosecone and parallel to the elongate body. The elongate body can include a flexible section proximally located relative to the fixed bend, wherein an extent of curvature of the flexible section is adjustable based on an extent of proximal movement of the cutter and the rotatable driveshaft relative to the catheter. The flexible section can be configured to take on an s-shaped curve upon proximal movement of the cutter and rotatable driveshaft within the catheter. The atherectomy device can further include a handle at a proximal end of the catheter, wherein the handle includes a lock configured to lock the flexible section in a curved shape. The lock can be configured to allow a user to choose a locked position of the driveshaft with respect to the catheter by <NUM> inches or less. The lock can include a slider button that is configured to slide distally and proximally. Sliding the slider button proximally can increase the curvature of the flexible section. The handle can include a spine joint that allows axial translation of the slider button with respect to the driveshaft while allowing the driveshaft to rotate with respect to the slider button. The flexible section can include a first portion axially adjacent to a second portion, the first portion having a first longitudinal spine and the second portion having a second longitudinal spine, wherein the first longitudinal spine and second longitudinal spine are on opposing sides of the flexible section, and wherein the force applied to the rotatable shaft in the proximal direction causes the first portion to bend laterally away from the first longitudinal spine and the second portion to bend laterally away from the second longitudinal spine. The elongate body can include a flexible section proximally located relative to the fixed bend, the flexible section including a first portion axially adjacent to a second portion, the first portion having a first longitudinal spine and the second portion having a second longitudinal spine, wherein the first longitudinal spine and second longitudinal spine are on opposing sides of the flexible section. Further proximal movement of the rotatable shaft can cause the flexible section to compress such that the first portion bends laterally away from the first longitudinal spine and the second portion bends laterally away from the second longitudinal spine, thereby causing the flexible section to take on an s-shape. The fixed bend can have an angle ranging from about <NUM>°-<NUM>°.

In some examples, a method of using an atherectomy device, the atherectomy device including a cutter coupled to a rotatable driveshaft within a catheter, the catheter having a distal nosecone fixedly coupled to a flexible section and a cutter window between the distal nosecone and the flexible section, the method includes: moving the rotatable driveshaft proximally within the catheter to cause the cutter to tilt in a first direction and extend through the cutter window; moving the rotatable driveshaft further proximally within the catheter to cause the flexible section to bend away from a longitudinal spine of the flexible section such that the flexible section takes on a curvature; and moving the rotatable driveshaft distally within the catheter to cause the cutter to tilt in a second direction opposite the first direction and to retract within the catheter. The method can further include moving the rotatable driveshaft distally within the catheter to cause the flexible section to straighten. Moving the rotatable driveshaft distally can include sliding a slider button on a handle of the atherectomy device distally, wherein moving the rotatable driveshaft proximally includes sliding the slider button proximally. The method can further include sliding a slider button on a handle of the atherectomy device proximally to increase the curvature of the flexible section. The method can further include selecting an extent of curvature of the flexible section by controlling distal and proximal movement of the slider button. The method can further include locking the flexible section in a curved shape by a selected curvature using a handle at a proximal end of the catheter. Moving the rotatable driveshaft proximally to extend the cutter through the cutter window can include causing a ledge of the cutter to slide along an edge of an inner surface of the catheter to move the cutter radially and extend the cutter through the cutter window. The edge can be sloped with respect to an axis perpendicular to the longitudinal axis of the distal nosecone. The edge can be configured to tilt the cutter with respect to the nosecone when the ledge of the cutter slides along the edge. The cutter window can be on a side of the catheter. The flexible section can include a first portion axially adjacent to a second portion, the first portion having a first longitudinal spine and the second portion having a second longitudinal spine, wherein the first longitudinal spine and second longitudinal spine are on opposing sides of the flexible section, and wherein moving the rotatable driveshaft further proximally causes the first portion to bend laterally away from the first longitudinal spine and the second portion to bend laterally away from the second longitudinal spine, thereby causing the flexible section to take on an s-shape. The method can further include rotating the rotatable driveshaft while capturing images outside of the catheter using an imaging sensor coupled to the rotatable driveshaft. The method can further include cutting tissue outside of the catheter by rotating the rotatable driveshaft.

In some examples, a method of using an atherectomy device, the atherectomy device including a cutter coupled to a rotatable driveshaft within a catheter, the catheter including a nosecone fixedly coupled to an elongate body at a fixed bend of the catheter, the method includes: moving the rotatable driveshaft proximally within the catheter to cause the cutter to tilt in a first direction and to extend though the cutter window; and moving the rotatable driveshaft distally within the catheter to cause the cutter to tilt in a second direction opposite the first direction and to retract the cutter within the cutter window. The fixed bend can have an angle ranging from about <NUM>°-<NUM>°. The cutter can move radially with respect to the catheter when extending through the cutter window. At least a portion of a cutting edge of the cutter can correspond to a most prominent point along the convex side of the fixed bend when the cutter is extended through the cutter window. A cutting edge of the cutter can extend through the cutter window in an active mode, and wherein the cutting edge of the cutter is retracted within the catheter in a passive mode. The cutter can be substantially parallel to the nosecone in the active mode and substantially parallel to the elongate body in the passive mode. The cutting edge of the cutter can be held in the passive mode by a detent, the method further comprising applying a threshold translational force to the rotatable driveshaft to release the detent and transition the cutter from the passive mode. The cutter can be rotatable when in the active mode and the passive mode. The method can further include collecting images outside of the catheter using an imaging sensor coupled to the rotatable driveshaft. The catheter can include one or more openings configured to align with the imaging sensor and act as a location marker for the imaging sensor. Moving the rotatable driveshaft proximally to extend the cutter through the cutter window can include causing a ledge of the cutter to slide along an edge of an inner surface of the catheter to move the cutter radially and extend the cutter through the cutter window. The method can further include moving the cutter distally to pack tissue into the nosecone. Moving the rotatable driveshaft proximally within the catheter to cause the cutter to tilt in the first direction and to extend though the cutter window can include transitioning the cutter between being parallel to the nosecone and parallel to the elongate body. The elongate body can include a flexible section proximally located relative to the fixed bend, the method further comprising moving the rotatable driveshaft further proximally within the catheter to cause the flexible section to bend. The method can further include adjusting a curvature of the bend by controlling an extent of proximal movement of the rotatable driveshaft within the catheter. The flexible section can be configured to take on an s-shaped curve upon the proximal movement of the rotatable driveshaft within the catheter. The method can further include locking the flexible section in a curved shape by a selected curvature using a handle at a proximal end of the catheter. Moving the rotatable driveshaft distally can include sliding a slider button on a handle of the atherectomy device distally, wherein moving the rotatable driveshaft proximally includes sliding the slider button proximally. The method can further include sliding a slider button on a handle of the atherectomy device proximally to increase a curvature of a flexible section of the elongate body. The method can further include locking the cutter in an active mode where the cutter extends through the cutter window. Moving the rotatable driveshaft proximally can include pressing on and proximally moving a slider button on a handle of the atherectomy device, wherein locking the cutter in the active mode includes releasing the slider button. The method can further include locking the cutter in a passive mode where the cutter is retracted within the cutter window. Moving the rotatable driveshaft distally can include pressing on and distally moving a slider button on a handle of the atherectomy device, wherein locking the cutter in the passive mode includes releasing the slider button. The method can further include rotating the rotatable driveshaft while capturing images outside of the catheter using an imaging sensor coupled to the rotatable driveshaft. The method can further include cutting tissue outside of the catheter by rotating the rotatable driveshaft.

These and other aspects and advantages are described herein.

A better understanding of the features and advantages of the present invention will be obtained by reference to the following detailed description that sets forth illustrative embodiments, in which the principles of the invention are utilized, and the accompanying drawings of which <FIG> show embodiments according to the invention, and the rest of the figures are considered useful to understand it.

Described herein is an atherectomy catheter having an elongate body with a curved distal portion, a nosecone and a rotatable annular cutter. The curved portion (which can otherwise be called a bent/bendable portion or jog mechanism) can advantageously be used to push the cutter up against the vessel wall to enhance the efficiency of cutting.

<FIG> and <FIG> show an exemplary atherectomy catheter <NUM> having a curved portion along the elongate catheter body. Referring to <FIG>, the atherectomy catheter <NUM> can include a catheter body <NUM> with a curved portion <NUM>, a rotatable annular cutter <NUM> at a distal end of the catheter body <NUM>, and a nosecone <NUM> at a distal end of the catheter body <NUM>. The nosecone <NUM> can include a cutting window <NUM> configured to allow the cutter <NUM> to cut therethrough. The catheter <NUM> can further include a curved portion <NUM> in the catheter body <NUM> to radially push the cutter <NUM> against the vessel wall.

The curved portion <NUM> can be a fixed jog (i.e., have a pre-set shape). Further, the curved portion can be curved or bent such that the cutting window <NUM> is on the radially outermost portion of the curved portion <NUM> (thereby allowing the cutting window <NUM> to be urged against a vessel wall in use). In one embodiment, the curved portion <NUM> can be preformed, for example, by using pre-deflected shaped-set nitinol ribbon segments embedded in the outer shaft. The curved portion <NUM> can have a shape that advantageously positions the cutter <NUM> with respect to the vessel wall for cutting. In some cases, the curved portion <NUM> can have two inflection points <NUM>, <NUM> of opposite curvature (i.e., one curving up and the other curving down) so as to form an approximate "s" shape. In one embodiment, the s-shape can be configured such that a distal end of the catheter body <NUM> is offset from, but substantially parallel to, a proximal end of the catheter body <NUM>. In other embodiments, the distal end and proximal ends of the catheter body <NUM> can be at a slight angle to one another so as to control the angle of cutter engagement with the vessel wall.

Thus, as shown in <FIG>, the "s-shape" of the curved portion <NUM> can include a proximal section <NUM> have a length b that extends from the center of the distal inflection point <NUM> to the center of the proximal inflection point <NUM>. Further, the curved portion <NUM> can include a distal section <NUM> having a length a that extends from the cutting edge <NUM> to the center of the distal inflection point <NUM>. Further, there can be distal angle <NUM> at the distal end of the "s-shape" and a proximal angle <NUM> at the proximal end of the "s-shape. " These lengths (a, b) and angles (<NUM>, <NUM>) can be tuned to achieve the desired jog or offset in order to obtain optimum apposition to tissue walls. For example, the length a can be shorter than the length b to ensure that the cutter is as close to the angle <NUM> as possible, thereby providing better apposition of the cutter <NUM>. The angles <NUM> and <NUM> can be between <NUM> and <NUM> degrees, such as between <NUM> and <NUM> degrees. In one example, the length a is between <NUM> and <NUM>, the length b is between <NUM> and <NUM>, the angle <NUM> is <NUM> degrees and angle <NUM> is <NUM> degrees for a catheter configured to be used in a vessel having a <NUM>-<NUM> diameter.

The curved portion <NUM> can advantageously radially push the distal end of the catheter against a vessel wall <NUM>, thereby enabling optimized cutting and/or imaging of the vessel as shown in <FIG>.

<FIG> show another embodiment of an exemplary catheter <NUM> that includes a curved portion <NUM> in the catheter body that urges the atherectomy cutter against the vessel wall. The curved portion <NUM> can have similar dimensions and features as curved portion <NUM>. In contrast to the fixed jog curved portion <NUM> of catheter <NUM>, however, the curved portion <NUM> can be a user-activated jog. Thus, referring to <FIG> and <FIG>, the catheter <NUM>, can be deflected into a curved portion <NUM> by tensile and compressive interaction between an inner shaft <NUM> (which can be a drive shaft for a cutter) and outer shaft <NUM> that are fixed together at the distal end but free to move relative to one another at the proximal end. The outer shaft <NUM> can include stiffening members 377a,b, such as nitinol or stainless steel, stiffening members, configured to bias the deflection to a set shape. As shown in <FIG>, there can be two stiffening members 377a, 377b that can be axially aligned with the outer shaft <NUM> and axially and radially offset from one another. As a result, when compression is applied on the outer shaft <NUM> (such as by pulling on the inner shaft <NUM> or a separate pullwire or shaft), the portions 379a,b of the outer shaft opposite to the stiffening members 377a,b will contract. The contraction of the two portions 379a, 379b will result in an s-shape similar to the catheter <NUM> shown in <FIG>. As a result, the catheter will deflect into jog or s-shaped configuration where the distal end of the shaft is offset and parallel to the main shaft body. It is to be understood that other numbers and arrangements of stiffening members are possible, as are other resulting jog shapes.

Another embodiment of an atherectomy catheter <NUM> including a user-activated curved portion <NUM> is shown in <FIG>. The atherectomy catheter <NUM> includes an elongate body <NUM>, a nosecone <NUM> attached thereto, and a cutting window <NUM> configured to expose an annular cutter <NUM> therethrough. Moreover, the catheter <NUM> includes a curved portion <NUM>. The curved portion <NUM> includes curved sections <NUM>, <NUM> of opposite curvatures (i.e., one curving up and the other curving down) so as to form an approximate s-shape. In one embodiment, the s-shape can be configured such that the distal end of the catheter body <NUM> and/or the nosecone <NUM> is offset from, but substantially parallel to, a proximal end of the catheter body <NUM>. In another embodiment, the distal end of the elongate body <NUM> and/or the nosecone <NUM> forms an angle relative to a proximal end of the catheter body <NUM>.

Thus, as shown in <FIG>, the "s-shape" of the jog <NUM> can have a proximal curved section <NUM> and a distal curved section <NUM> having a length c. Further, there can be distal angle <NUM> at the distal end of the "s-shape" and a proximal angle <NUM> at the proximal end of the "s-shape. " The lengths (c, d) and angles (<NUM>, <NUM>) of the jog <NUM> can be tuned to achieve the desired jog or offset in order to obtain optimum apposition to tissue walls. For example, the angles <NUM> and <NUM> can be between <NUM> and <NUM> degrees, such as between <NUM> and <NUM> degrees. Further, in some embodiments, the length d of the proximal section <NUM> is greater than the length c of the distal section <NUM>. In one example, the length c is <NUM>, the length d is <NUM>, and the angles <NUM> and <NUM> are <NUM> degrees for a catheter configured to be used in a vessel having a <NUM>-<NUM> diameter. The curved portion <NUM> can be a configured to adopt the s-shape during use of the catheter, as described above with respect to curved portion <NUM>.

An exemplary user-activated curved portion <NUM> (e.g., for use as curved portion <NUM>) is shown in <FIG>. The curved portion <NUM> can include a frame (e.g., made of Nitinol or stainless steel) including a series of circumferential slits <NUM> (e.g., laser cuts) that are patterned along the circumference of the elongate body <NUM> within the curved sections <NUM>, <NUM>. The frame of the curved sections <NUM>, <NUM> can also include a longitudinal spine 560a,b (also referred to herein as a backbone) extending therethrough. The longitudinal spines 560a,b can be positioned approximately <NUM> degrees away from one another (i.e., on opposites sides of the elongate body <NUM>) and extend substantially parallel to the longitudinal central axis of the elongate body <NUM>. The frame can further include a circumferential spine <NUM> separating the two curved sections <NUM>, <NUM>. Each spine 560a,b and <NUM> is formed of a substantially solid piece of material that does not include slits therein. In use, as the circumferential slits <NUM> compress and/or overlap with one another during bending, the longitudinal spines 560a,b form the backbone of the curved sections <NUM>, <NUM>. Further, in some embodiments, the frame can be laminated with a layer thereover and/or under, such as a thin polymer layer, such as Tecothane. In other embodiments, the frame is not laminated to provide for greater flexibility.

Referring to <FIG>, the slits <NUM> can be arranged in a pattern that is configured to provide flexibility while maintaining structural integrity of the elongate body. Thus, the majority of the slits <NUM> can have the same length, but be offset from one another. For example, the slits in distal section <NUM> can be arranged in rows (<NUM>,<NUM>) and columns (A, B). Each slit <NUM> (except the shorter slits bordering the spine 560a) can have a length equivalent to the width of columns A + B + A. Further, the slits can be offset from one another by a distance of A + B. Thus, each column A can include slits from every row <NUM>,<NUM> while column B can include alternating slits (from either row <NUM> or <NUM>). Column B thus provides structural integrity to the slitted portion of the device. The slits in section <NUM> can be similarly arranged, but can be offset such that each column C (with slits from every row <NUM>,<NUM>) is aligned with the central axis of each column D (with slits from row <NUM> or <NUM>). The offset helps provide stability to the catheter as it bends.

In some examples, pushing or pulling on a shaft of the catheter, such as the cutter drive shaft, a pullshaft, or a pullwire can activate the curved portion <NUM>. That is, as the shaft is pulled back proximally, it can place compression on the outer elongate body <NUM>, causing the slits <NUM> to compress and/or move over one another while the spines 560a,b maintain their length. The resulting s-shape (see <FIG>) allows the cutter (just distal to spine 460a) to be pushed up against the vessel wall.

The slits <NUM> shown in <FIG> are of a repeated, symmetrical pattern. However, the pattern need not be symmetrical. In some embodiments, the slits can all have the same length. In other embodiments, some of the slits are longer than others. In one embodiment, the slits are. <NUM>" wide and. <NUM>" long with a. <NUM>" offset from the next row of slits.

Areas of the catheter body having a greater degree of slits will be more flexible than those having lesser degrees of slits. In one embodiment, the slits can extend all the way through the elongate catheter. In other instances, some of the slits may be deeper or shallower than others which also affects the flexibility of the corresponding region. In some variations of the curved portion, a range of deflection between the flexible segments may be achieved. This may be accomplished through different geometric patterns of slits, different spacing of the slits, frequency of the slits, size of the slits, and so forth. In some instances, the degree of stiffness may be adjusted by adding additional spines of various lengths in certain areas or adjusting the width of the spines.

Referring to <FIG>, another exemplary curved portion <NUM> (e.g., for use as curved portion <NUM>) is shown. The curved portion <NUM> includes a frame having three annular ring spines 661a,b,c connected together by two longitudinal spines 660a,b. The longitudinal spines 661a,b,c can be approximately <NUM>° away from one another. In some embodiments, the distal ring 661a,bc can be beveled at the distal end, as shown in <FIG>, to allow for dropping or pivoting of the nosecone <NUM>. Further, the space between the annular ring spines 661a,b,c and the longitudinal spines 660a,b can be open or cut-away (i.e., not include the frame material). In some embodiments, the frame can be laminated to the elongate body <NUM> with one or more thin polymer layers, such as Tecothane. The ring 661a,b,c can include holes therein for soldering or laminating the mechanism <NUM> to the elongate body of the catheter. In other embodiments, the frame can remain unlaminated to provide for greater flexibility. When compression is placed upon the mechanism <NUM>, the mechanism <NUM> can bend away from each of the spines <NUM>, forming an s-shape. For example, compression can be placed on the mechanism <NUM> by pulling the driveshaft is pulled proximally.

Referring to <FIG>, another exemplary atherectomy catheter <NUM> with a curved portion <NUM> is shown. The atherectomy catheter <NUM>, like atherectomy catheter <NUM>, can include a catheter body <NUM> with curved portion <NUM>, a rotatable annular cutter <NUM> at a distal end of the catheter body <NUM>, and a nosecone <NUM> at a distal end of the catheter body <NUM>. The catheter body <NUM> and/or nosecone <NUM> can further include a cutting window <NUM> configured to allow the cutter <NUM> to cut therethrough. The catheter <NUM> can further include a driveshaft (not shown) attached to the cutter <NUM> and configured to rotate the cutter <NUM> when activated. In this embodiment, the nosecone <NUM> is not hinged relative to the elongate body <NUM>. Rather, the bushing <NUM> of the elongate body <NUM> attaches directly to the proximal end of the nosecone <NUM>. Not having a hinge can advantageously prevent the nosecone <NUM> from getting caught within the vessel. In this embodiment, proximal or distal movement of the cutter <NUM> and driveshaft can activate the curved portion <NUM> to push the cutter <NUM> radially against the vessel well (e.g., outside the cutting window <NUM>).

The curved portion <NUM> includes a tubular frame having a proximal section 992a and a distal section 992b. Each section 992a, 992b includes a longitudinal spine 960a,b. The longitudinal spines 960a,b are positioned approximately <NUM> degrees away from one another. Circumferential cuts <NUM> (e.g., laser cuts) having a jigsaw pattern that define tongue elements 965a,b,c (see <FIG>) can be positioned opposite each spine 960a,b. In some embodiments, the jigsaw pattern includes holes <NUM> where the cuts <NUM> terminate at the spines 960a,b. When compression is placed upon the mechanism <NUM>, the mechanism <NUM> can bend into an s-shape with the proximal section 992a bending in a first direction and the distal section 992b bending in a second opposite direction. As shown in <FIG>, during such bending, the spines 933c do not compress and thereby forming the outer diameter of each respective curve and the cuts <NUM> compress together to form the inner diameter of each respective curve.

In some embodiments, the tongue elements 965a,b,c can have a tapered structure configured to dictate the amount of deflection of the curved portion <NUM> in both directions. For example, the tongue elements 965a,b,c can lock with respect to one another in the curved position, thereby keeping the curved portion <NUM> aligned and resistant to twisting when under torsion when in the curved or deflected position. This can also prevent the curved portion <NUM> from over-bending.

In some embodiments, the proximal section 992a can be longer than the distal section 992b. For example, the proximal section 992a can form <NUM>-<NUM>%, such as <NUM>%-<NUM>% of the length of the curved portion <NUM> while the distal section 992b can form <NUM>%-<NUM>%, such as <NUM>%-<NUM>% of the length of the curved portion <NUM>. Having a longer distal section 992b than proximal section 992a can advantageously help ensure that the cutter <NUM> is forced against the vessel well during use without tipping back down towards the center of the vessel.

The curved portion <NUM> can be coupled to the outer shaft of the atherectomy catheter using any technique, such as welding, adhesive, fastener(s), or a combination thereof (e.g., via holes <NUM>).

Referring to <FIG>, in any of the embodiments described herein, the cutter <NUM> can include a proximal ledge <NUM> configured to interact with the bushing <NUM> on the curved portion <NUM> when the driveshaft <NUM> is pulled proximally. The curved portion <NUM> can correspond to a flexible section of the catheter. In embodiments wherein the nosecone <NUM> is not hinged, the interaction between the proximal ledge <NUM> and the bushing <NUM> can cause the cutter <NUM> to move through the window <NUM>. For example, the distal edge <NUM> of the bushing <NUM> can be angled such that, as the drive shaft <NUM> is pulled proximally, the ledge <NUM> slides along the sloped distal edge <NUM> (e.g., sloped with respect to an axis perpendicular to the longitudinal axis of the nosecone <NUM>) to move the cutter <NUM> out of the cutter window <NUM> (see the movement from <FIG>). That is, interaction between the ledge <NUM> and the edge <NUM> can cause at least a portion of the cutter to extend through (e.g., pop through) the window <NUM> and tilt such that the cutter <NUM> is at an angle relative to the nosecone <NUM> and the elongate body (e.g., <NUM> in <FIG>). In other words, movement of cutter <NUM> proximally relative to the nosecone can cause at least a portion of the cutter to extend through the window and cause a longitudinal axis of the cutter <NUM> to become non-parallel to a longitudinal axes of the nosecone <NUM> and the elongate body. In some embodiments, the longitudinal axis of the cutter <NUM> is at an angle ranging from about <NUM> degree and <NUM> degrees (e.g., <NUM>°-<NUM>°, <NUM>°-<NUM>°, <NUM>°-<NUM>°, <NUM>°-<NUM>°, or <NUM>°-<NUM>°) relative to the longitudinal axes of the nosecone <NUM> and elongate body when the cutter <NUM> is fully deployed.

In some embodiments, the interaction between the proximal ledge and the bushing can additionally or alternatively cause the curved portion (also referred to as a flexible section) to assume its s-shape. For example, referring to <FIG>, pulling the driveshaft <NUM> (shown cut off for clarity) proximally can cause the cutter <NUM> to engage with the bushing <NUM> to place compression on the curved portion <NUM> and force the curved portion <NUM> to bend (i.e., away from each of the longitudinal spines 1160a,b). In some embodiments, the amount of curvature can be incrementally and/or continuously adjustable by placing varying amounts of compression on the curved portion <NUM> via the driveshaft. Likewise, pushing the driveshaft <NUM> distally can straighten the curved <NUM>. A locking mechanism, such as a mechanism on the handle, can fix the curved portion <NUM> at the desired amount of curvature. An example of a handle with locking mechanism is described below with reference to <FIG>.

In some embodiments, the cutter <NUM> is pulled proximally by a first extent and/or at a first time to extend a portion of cutter <NUM> through the window <NUM> and tilt relative to the nosecone and elongate body (e.g., as shown in <FIG>), and pulled proximally by a second and/or at a second time to cause the flexible portion to bend and assume an s-shape to varying degrees depending on the amount of force applied to the driveshaft in the proximal direction (e.g., as shown in <FIG>).

Referring to <FIG>, in some embodiments, pulling the cutter <NUM> proximally (e.g., via the driveshaft) can first cause the cutter <NUM> to pop out of the cutter window <NUM>. Further proximal pulling on the cutter <NUM> can then cause the curved portion <NUM> to assume the desired s-shape (e.g., in a continuously adjustable manner). Having the cutter <NUM> pop out of the window first can advantageously ensure that the cutter <NUM> can be fully extended regardless of the assumed curvature. Pushing the cutter distally can cause the curved portion <NUM> to straighten to a desired extent. Further distal pushing on the cutter <NUM> can cause the cutter <NUM> to retract within the window <NUM>.

Referring to <FIG>, the nosecone <NUM> can be fixedly coupled to or integrally formed with the elongate body <NUM> at a fixed angle Θ relative to the elongate body. This fixed angle can form a fixed bend <NUM> (also referred to as a fixed curve) in the catheter between the nosecone <NUM> and the elongate body <NUM>. A cutting window <NUM> can provide access to the lumen of the catheter where the cutter <NUM> is housed. The cutting window <NUM> can be located adjacent to or at the fixed bend <NUM>. In some embodiments, the cutting window <NUM> is distally located along the catheter with respect to the bend. The cutter <NUM> can be configured to extend through the cutting window <NUM> upon translation of the cutter <NUM> and driveshaft relative the catheter (i.e., nosecone and elongate body). For example, the driveshaft and cutter <NUM> can be pulled to move the cutter <NUM> proximally and extend the cutter <NUM> though the cutting window. Likewise, the driveshaft and cutter <NUM> can be pushed to move the cutter <NUM> distally and retract the cutter <NUM> into the catheter housing.

The cutting window <NUM> can be on a convex side <NUM> of the catheter formed by the bend (e.g., as opposed to a concave side <NUM> of the catheter formed by the bend). This configuration can provide the rotating cutter <NUM> better access to material outside of the catheter for cutting. The angle Θ of the bend <NUM> can vary. In some embodiments, the angle Θ ranges from about <NUM> degree and <NUM> degrees (e.g., <NUM>°-<NUM>°, <NUM>°-<NUM>°, <NUM>°-<NUM>°, <NUM>°-<NUM>°, or <NUM>°-<NUM>°). Thus, in some embodiments, the angle of the bend <NUM> at the convex side <NUM> of the catheter may range from about <NUM>° and <NUM>° (e.g., <NUM>°-<NUM>°, <NUM>°-<NUM>°, <NUM>°-<NUM>°, <NUM>°-<NUM>°, or <NUM>°-<NUM>°).

The elongate body <NUM> can include a flexible section <NUM> consistent with the flexible section as described above with reference to <FIG> and <FIG>. For example, the flexible section <NUM> can be incrementally and/or continuously adjustable to take on an s-shape to varying degrees depending on an amount of proximal movement of driveshaft relative to the nosecone <NUM> and elongate body <NUM>. The flexible section <NUM> can have a greater flexibility than the nosecone <NUM>, the bend <NUM>, and in some cases a remainder of the catheter.

<FIG> show close-up partial section views of the bend <NUM>. The cutter <NUM> can be configured to transition between a passive mode, such as shown in <FIG>, and an active mode, such as shown in <FIG>. <FIG> shows the cutter <NUM> between the passive mode (<FIG>) and active mode (<FIG>).

Referring to <FIG>, when the cutter <NUM> is in passive mode, the cutting edge <NUM> of the cutter <NUM> can be distally located with respect to the window <NUM> and housed within the nosecone <NUM> such that the cutting edge <NUM> of the cutter <NUM> is fully protected and does not extend through the cutting window <NUM>. In the passive mode, the cutting edge <NUM> may be prevented from cutting material outside of the catheter, thereby preventing the cutting edge <NUM> from cutting tissue, for example, a vessel wall. The cutter <NUM> may be placed in the passive mode, for example, as the catheter is being maneuvered through the vessel to arrive at a target location within the vessel (e.g., to remove material such as plaque) and/or being withdrawn from the vessel (e.g., after removal of the material from the vessel). In the passive mode, a longitudinal axis (e.g., axis of rotation) of the cutter <NUM> can be substantially parallel to a longitudinal axis of the nosecone <NUM>. In the passive mode, the cutter <NUM> can be pushed distally toward the nosecone <NUM> to, for example, pack material (e.g., plaque) into the nosecone <NUM>.

Referring to <FIG>, when the cutter <NUM> is in the active mode, the cutting edge <NUM> of the cutter <NUM> can extend through the cutting window <NUM>. The cutter <NUM> (e.g., the cutting edge <NUM> of the cutter <NUM>) can extend beyond the outer walls on the convex side of the catheter so that the cutter <NUM> can efficiently access material outside of the catheter for cutting. For example, at least a portion of the cutter <NUM> (e.g., at least a portion of the cutting edge <NUM>) can correspond to the most prominent feature or point along the convex side of the bend when the cutter <NUM> is extended through the cutting window <NUM> (e.g., fully extended in the active mode). In the active mode, a longitudinal axis (e.g., axis of rotation) of the cutter <NUM> can be substantially parallel to a longitudinal axis of the elongate body (e.g., <NUM>, <FIG>). Since the cutter <NUM> can be parallel to the elongate body, the cutter <NUM> can be at the angle Θ (<FIG>) relative to the nosecone <NUM> when in the active mode.

<FIG> shows the cutter <NUM> between the passive mode and the active mode. The cutter <NUM> and driveshaft can be moved proximally (e.g., pulled away from the nosecone <NUM>) to transition the cutter <NUM> from the passive mode to the active mode. Likewise, the cutter <NUM> and driveshaft can be moved distally (e.g., pushed toward the nosecone <NUM>) to transition the cutter <NUM> from the active mode to the passive mode. During transition between the passive and active modes, the cutter <NUM> can be configured to interact with inner surfaces within the catheter to adjust the position and orientation of the cutter <NUM> relative to the nosecone <NUM> and the elongate body <NUM>.

During transition from the passive mode to the active mode, the cutter <NUM> (e.g., via the driveshaft) is pulled proximally to cause a proximal ledge <NUM> (also referred to as a proximal face) of a head <NUM> of the cutter <NUM> to slide along a distal edge <NUM> of a bushing <NUM>. This interaction causes the cutter <NUM> to move radially outward with respect to a central axis of the elongate body <NUM> and extend through the cutting window <NUM> (e.g., pop out of the window). This interaction also causes the cutter <NUM> to tilt such that a longitudinal axis of the cutter <NUM> aligns with (e.g., becomes substantially parallel to) a longitudinal axis of the elongate body <NUM>.

During transition from the active mode to the passive mode, the cutter <NUM> (e.g., via the driveshaft) is pushed distally to cause a slanted surface <NUM> along the shaft <NUM> of the cutter <NUM> to slide along an internal edge <NUM> of the bushing <NUM> to cause the cutter <NUM> to move radially inward with respect to a central axis of the elongate body <NUM> and retract into the catheter. When the cutter <NUM> is moved radially inward, the shaft <NUM> of the cutter <NUM> contacts an internal surface <NUM> of the bushing <NUM>, causing the cutter <NUM> to tilt such that the longitudinal axis of the cutter <NUM> aligns with (e.g., becomes substantially parallel to) a longitudinal axis of the nosecone <NUM>.

The transitions between the passive and active modes can be continuous, where the cutter <NUM> progressively translates, tilts and moves radially. The cutter <NUM> and drive shaft can freely rotate while in the passive mode and the active mode. In some cases, the cutter <NUM> can also freely rotate while transitioning between the passive mode and the active mode.

The cutter <NUM> can be locked in either the passive or active modes using a locking mechanism of the handle. An example of a locking mechanism is described below with reference to <FIG>.

Any of the catheters described herein may include imaging capabilities such as described in International Application Nos. <CIT> and <CIT>, each of which is cited for reference. For example, the cutter <NUM> can include a cavity <NUM> for an imaging sensor within the catheter to send and/or receive image data as part of an imaging system. The cutter <NUM> may be configured to collect imaging data while in the passive mode, the active mode and/or while transitioning between the active and passive modes. In some embodiments, the catheter includes one or more openings <NUM> that act as an additional window and/or as a location marker(s) for the imaging sensor.

<FIG> and <FIG> show perspective and section views of an example cutter <NUM> and bushing <NUM>. The cutter <NUM> can include a head <NUM> at a distal end, a neck <NUM>, and a cylindrical shaft <NUM> at a proximal end. The head <NUM> can include an annular cutting edge <NUM>, which may scalloped in some embodiments. The neck <NUM> can have a smaller diameter than the head <NUM> and the proximal shaft <NUM> to provide a clearance for the cutter <NUM> when rotating in the active mode. In some embodiments, the shaft <NUM> can include an annular groove <NUM> that cooperates with the bushing <NUM> to function as a detent (described in detail below). The bushing <NUM> can be fixedly coupled to and be positioned between the distal nosecone (e.g., <NUM>, <FIG>) to the proximal elongate body (e.g., <NUM>, <FIG>). In some cases, the bushing <NUM> is welded to the nosecone and/or the elongate body. The bushing <NUM> can include a first portion <NUM> that is substantially parallel the nosecone, and a second portion <NUM> that is substantially parallel the elongate body. An intervening portion <NUM> can be between the first portion <NUM> and the second portion <NUM>.

As described above, features of the bushing <NUM> interact with the cutter <NUM> to control movement of the cutter <NUM> between active and passive modes. When the cutter <NUM> is pulled proximally (e.g., from the passive mode to the active mode), the proximal ledge <NUM> (also referred to as a proximal face) of the head <NUM> of the cutter <NUM> can be configured to slide along a distal edge <NUM> of the bushing <NUM>. This interaction causes the cutter <NUM> to move radially outward and extend through the cutting window. This cutter <NUM> becomes positioned within a notch <NUM> (also referred to as a seal or indentation) of the distal face of the bushing <NUM>, which provides a space for the proximal ledge <NUM> of the cutter <NUM> to rotate in the active mode. As shown in <FIG>, the distal edge <NUM> may form a crescent-shaped step in accordance with the cylindrical head <NUM> of the cutter <NUM>.

Referring to <FIG>, the bushing <NUM> can include an internal edge <NUM> that is configured to slide along an angled surface <NUM> the cutter <NUM> when the cutter is pushed distally (e.g., from the active mode into the passive mode), causing the cutter <NUM> move radially inward. Additionally, an internal surface <NUM> of the bushing <NUM> contacts the shaft <NUM> of the cutter <NUM> to cause the cutter <NUM> to tilt and move in alignment with and retract within the nosecone, as described above.

<FIG> shows alternate views of the bushing <NUM>, illustrating a proximal side (<FIG>), a distal side (<FIG>), and section views (<FIG>) of the bushing. A proximal opening <NUM> of the bushing can have an oblong shape to provide clearance for the shaft of the cutter when transitioning between the active and passive modes. The internal surfaces of the bushing can form a first channel <NUM> for the cutter while in the passive mode and a second channel <NUM> for the cutter while in the active mode. The first channel <NUM> and the second channel <NUM> can be configured to retain the cutter at different angles based on whether the cutter is in the passive mode or active mode. The first channel <NUM> can retain the cutter in alignment with (e.g., parallel to) the nosecone, and the second channel <NUM> can retain the cutter in alignment with (e.g., parallel to) elongate body. The first distal surface <NUM> can be on a protruding lip <NUM> on the distal end of the bushing. As described above, the first distal surface <NUM> of the bushing can slide along an angled surface a proximal face of the head of the cutter to urge the cutter from the passive mode to the active mode. Also as described above, a surface <NUM> of the bushing can slide along an angled surface along the shaft of the cutter to urge the cutter from the active mode to the passive mode.

As described above, the cutter <NUM> can be retained in the passive mode by detent mechanism. <FIG> shows an annular groove <NUM> on the shaft <NUM> of the cutter <NUM>, which provides a clearance <NUM> (also referred to as a gap) between the cutter and a protruding surface <NUM> of the bushing. The clearance <NUM> allows the cutter to rotate more freely when the annular groove <NUM> is aligned with the internal surface <NUM> and the cutting edge of the cutter is housed within the catheter in the passive mode. This configuration can act as a detent to retain the cutter <NUM> in the passive mode. For instance, when the cutter is pushed more distally toward the nosecone (e.g., during packing of material into the nosecone) or when the cutter <NUM> is pulled more proximally during transition to the active mode, the groove <NUM> is not aligned with the internal surface <NUM>. This causes portions of the shaft <NUM> on either side of the groove <NUM> to contact the internal surface <NUM> of the bushing <NUM>, thereby increasing a drag (friction) between the cutter <NUM> and the bushing <NUM>. A threshold translational force applied to the cutter <NUM> may be required, either in the distal or proximal direction, to release the detent retaining the cutter <NUM> in the passive mode.

In some embodiments, any of the atherectomy devices described herein may not include imaging capability.

Referring to <FIG> and <FIG>, in some embodiments, an atherectomy catheter <NUM> can include a curved portion <NUM> that includes a fixed jog section <NUM> and a flexible section <NUM>. The fixed jog section <NUM> can either be proximal to the flexible section <NUM> (as shown) or distal to the flexible section <NUM>. In some embodiments, the fixed jog section <NUM> is longer than the flexible section <NUM>. For example, the fixed jog section <NUM> can be <NUM>-<NUM>, such as <NUM>, and the flexible section <NUM> can be <NUM>-<NUM>, such as <NUM>. Further, in some embodiments (as shown), the fixed jog section <NUM> can include only a single curve rather than a double curve (e.g., forming a c-shape rather than an s-shape). The angle of the curve can be, for example, <NUM>° to <NUM>°, such as <NUM>° to <NUM>°, such as approximately <NUM>°. The flexible section <NUM> can be configured to bend passively during use (i.e., when acted upon by the vessel wall), for example to form an angle of between <NUM>° and <NUM>°, such as <NUM>-<NUM>°, such as <NUM>°-<NUM>°.

In some embodiments, the curved portion <NUM> can be made of a laminated frame. Referring to <FIG>, the curved portion <NUM> can include a frame that includes a plurality of circumferential slits 750a,b extending therethrough. The slits 750a of the flexible section <NUM> can extend entirely around the circumference (i.e., include no longitudinal spine therein) while the slits 750b of the fixed jog section <NUM> can end at a longitudinal spine <NUM> extending through the fixed jog section <NUM>. An annular spine <NUM> can separate the flexible section <NUM> and the fixed jog section <NUM>. The frame can be made, for example, of Nitinol or stainless steel. Further, the frame can be laminated with a thin layer of polymer, such as Tecothane, on one or both sides. In some embodiments, only the fixed jog section <NUM> is laminated while the flexible section <NUM> remains unlaminated.

Referring to <FIG>, the slits 750a,b can be arranged in a pattern that is configured to provide flexibility in the flexible section <NUM> while maintaining structural integrity of the elongate body in both the flexible section <NUM> and the fixed jog section <NUM>. Thus, the majority of the slits 750a,b can have the same length, but be offset from one another. For example, the slits 750a in the flexible section <NUM> can be arranged in rows (<NUM>,<NUM>) and columns (A, B). Each slit 750a can have a length equivalent to the width of columns A + B + A. Further, the slits can be offset from one another by a distance of A + B. Thus, each column A can include slits from every row <NUM>,<NUM> while column B can include alternating slits (from either row <NUM> or <NUM>). Column B thus provides structural integrity to the slitted portion of the device. The slits 750a of the flexible section <NUM> can provide flexibility to allow the catheter <NUM> to achieve the desired curvature in any direction when inside the body (i.e., the slits can pull apart on the outside of the curve and compress and/or overlap when on the inside of the curve). For example, the flexible section <NUM> can bend to align the cutter with the edge of the vessel.

Further, the slits 750b in fixed jog section <NUM> (except the shorter slits bordering the spine 560a) can likewise have a length equivalent to the width of columns A + B + A. Further, the slits can be offset from one another by a distance of A + B. Thus, each column A can include slits from every row <NUM>,<NUM> while column B can include alternating slits (from either row <NUM> or <NUM>). In fixed jog section <NUM>, however, the spine <NUM> can be heat-set to set the angle of the jog, fixing the jog.

The curved sections described herein can additionally or alternatively include any of the selective bending support features described in International Application No. <CIT> (the '<NUM> application).

In some embodiments, the selective bending support features described in the '<NUM> application can be modified to take the s-shape as described herein, such as by including spines on opposite sides of the shaft. Additionally, in some embodiments, the selective bending support features described in the '<NUM> application can be modified so as to be activated by compression (e.g., by pulling on the driveshaft of an atherectomy catheter as described herein) rather than via tension.

In some embodiments, the curved portions of the elongate catheter bodies described herein can form a substantially s-shape with two different inflection points of opposite curvatures. In other embodiments, the curved portion can include a single inflection point that forms a substantially C-shape. Further, in some embodiments, one or more of the curves can be fixed. In other embodiments, one or more of the curves can be user activated (e.g., by pulling on the driveshaft or a separate pullshaft or wire). Further, any of the designs described herein can include a flexible section (e.g., of the elongate body or the nosecone) that allows the catheter to take the desired curvature during use.

In some embodiments, the amount of curvature of the user-adjusted curved portions can be further adjusted either prior to or during an atherectomy procedure based on the curvatures of the artery and the location of the plaque formation. For example, by tensioning a shaft of the catheter, the curved portion can constrict and adopt a sharper angle. Alternatively, when the shaft is relaxed, the curved portion can relax and adopt a wider angle. In such examples, the angles of deflection may be adjusted, for example, by <NUM> to <NUM> degrees. Further, the shape and angle can be incrementally and/or continuously adjustable, as described herein.

In some embodiments, the user-adjusted curved portions can have a pre-shaped bend or curvature that can be further adjusted prior to or during an atherectomy procedure. In other embodiments, the curved portions can be straight before the user-activated bend is activated.

In any of the embodiments described herein, the nosecone can be configured to hold tissue that is debulked by the cutter. Further, the driveshaft and cutter can be configured to move distally to pack tissue into the nosecone.

In some embodiments, lamination of a framework can cause the laminating material to heat and shrink, pushing into open slits and fixing the shape of the frame (e.g., in a pre-shaped jog). For example, the curved portions <NUM> and/or <NUM> can be laminated so as to create a fixed jog that can either be further adjusted by pulling on the driveshaft or that remains fixed throughout the procedure. In other embodiments, lamination of the framework can keep the slits open and free of material, allowing for greater flexibility.

Although described herein as being activated via compression (e.g., pulling on a driveshaft), the curved portions described herein can alternatively be activated via tension (e.g., pushing on a driveshaft).

The atherectomy catheters having a curved portion described herein advantageously allows easier and closer positioning of the atherectomy cutter to plaque close to the inner artery walls. That is, the curved portions can be configured such that the exposed portion of the cutter (e.g., the area extending through the cutter window) moves closer to the vessel wall than the unexposed side of the cutter. This positioning can make cutting during the atherectomy procedure more efficient.

Any of the curved portions described herein may be used alone or in combination with a mechanism to deflect the nosecone. In some embodiments, the nosecone can be deflected by pulling on a cutter driveshaft. Such deflection mechanisms are described in <CIT>, titled "ATHERECTOMY CATHETERS DEVICES HAVING MULTI-CHANNEL BUSHINGS," now <CIT>, and <CIT>, titled "ATHERECTOMY CATHETERS AND OCCLUSION CROSSING DEVICES," now <CIT>. In some embodiments, placing further tension on the drive shaft (i.e., after exposing the nosecone) can result in compression being applied to the curved portion, causing the curved portion to assume its final curved configuration. Having both the nosecone deflect and the curved portion can result in better tissue invagination and thus better or more efficient tissue cutting.

In embodiments where the nosecone is not deflected, the respective cutting windows can be optimized so as to allow for automatic invagination of tissue into the cutting window. Further, having the nosecone not deflect and relying entirely on the curved portion for tissue apposition can advantageously prevent the cutter from escaping from the nosecone during packing. Further, having the curved portion alone (i.e., without the nosecone activation) can advantageously eliminate having to use additional mechanisms to force a jog mid-surgery, such as pulling or pushing on a shaft, thereby enhancing both ease of use and enhancing image stability.

Referring to <FIG>, in some embodiments, the nosecone <NUM> can be flexible. That is, the elongate body can include one or more curves (as described herein), and the nosecone <NUM> can provide additional flexibility to allow the catheter to take the desired shape. The nosecone <NUM> can, for example, include a repeating laser cut pattern covered in a laminate layer. As shown in <FIG>, the pattern can include a series of spiral slits <NUM> extending around the circumference of the nosecone. In some embodiments, the laser cut pattern can be cut out of stainless steel, which can be laminated with a polymer, such as Tecothane. Additional flexible nosecone designs are described in <CIT> titled "TISSUE COLLECTION DEVICE FOR CATHETER," now <CIT> and International Patent Application No. <CIT> and titled "CATHETER DEVICE WITH DETACHABLE DISTAL END". The flexible nosecone can be used in addition to, or in place of, any feature of the elongate body curved portions described herein.

Any of the catheter devices described herein can include an imaging system for collecting images outside of the catheter. In some embodiments, the imaging system includes a side-facing optical coherence tomography (OTC) system coupled to a cutter and driveshaft for collecting images outside of catheter while the cutter and driveshaft are rotating. Example suitable imaging systems are described in International Application Nos. <CIT> and <CIT>.

Any of the catheter devices described herein can include a lock assembly for locking an axial position of the driveshaft (inner shaft) relative to the outer shaft (catheter). The lock assembly can be used, for example, to maintain the catheter distal assembly in a curved or straight state or to keep the cutter positioned outside or inside of the cutter window. In some cases, the lock assembly allows for continuous adjustment of the curvature of the catheter as described herein. In some examples, the locking mechanism is in the handle of the catheter device. <FIG> show an example of a slider lock <NUM> in a handle <NUM> of the catheter device. In <FIG>, the slider lock <NUM> is in a distal position where a slider button <NUM> is most distally positioned. The inner driveshaft includes a hypotube <NUM> and a drive key <NUM>. The drive key <NUM> has a square cross-sectional shape that fits within a correspondingly square shaped opening of a distal end of a cradle <NUM>. This configuration forms a spline joint assembly <NUM> that rotationally couples the drive key <NUM> to the cradle <NUM> but also allows for axial translation of the drive key <NUM> relative to the cradle <NUM>. Thus, when the cradle <NUM> is rotated by the drive motor, the inner driveshaft (drive key <NUM> and the hypotube <NUM>) also rotates, while the spline joint assembly <NUM> allows for axial translation of the inner driveshaft (drive key <NUM> and the hypotube <NUM>) relative to the cradle <NUM> and the drive motor. A connector piece <NUM> is positioned around the drive key <NUM> and is used translationally couple the slider button <NUM> to the drive key <NUM> while allowing the drive key <NUM> to rotate independently of the slider button <NUM>. The connector piece <NUM> includes a bearing <NUM> (e.g., ball bearing) that allows the drive key <NUM> to rotate within the connector piece <NUM>. The slider button <NUM> is rigidly coupled to the connector piece <NUM>. Thus, distal and proximal movement of the slider button <NUM> causes corresponding distal and proximal movement of the inner driveshaft (drive key <NUM> and the hypotube <NUM>). In this way, the spine joint <NUM> allows axial translation of the slider button with respect to the driveshaft while allowing the driveshaft to rotate with respect to the other parts of the handle assembly including the slider button.

A curved disc spring <NUM> provides resistance against the slider button <NUM> to keep teeth <NUM> of the slider button <NUM> engaged with corresponding teeth <NUM> within the housing of the handle <NUM>, thereby locking an axial position of the driveshaft in place. To move the slider button <NUM>, a user presses the slider button <NUM> radially inward to compress the disc spring <NUM> and cause the teeth <NUM> of the slider button <NUM> to disengage from the teeth <NUM> within the housing of the handle <NUM>, as shown in <FIG>. When the slider button <NUM> is pressed, the user can slide the slider button <NUM> proximally or distally. The slider button <NUM> is positioned within an opening of the housing of the handle <NUM>, where the opening is defined by a distal edge <NUM> and a proximal edge <NUM> that limit the distal and proximal movement of the slider button <NUM>. Thus, when the user presses on the slider button <NUM>, the user can translate the slider button <NUM> by any distance between the distal edge <NUM> and the proximal edge <NUM>. When the user releases pressure from the slider button <NUM>, the disc spring <NUM> applies pressure back on the slider button <NUM> to reengage the teeth <NUM> of the slider button <NUM> with the teeth <NUM> of the housing of the handle <NUM>, thereby relocking a position of the driveshaft relative to the non-translating parts of the catheter assembly, including the outer shaft. A user can choose an extent to which the driveshaft is translated within the outer shaft as long as the translation of slider button <NUM> is between the distal edge <NUM> and the proximal edge <NUM>. The distance between the distal edge <NUM> and the proximal edge <NUM> can vary depending on design requirements. In some examples, the distance between distal edge <NUM> and the proximal edge <NUM> ranges from about <NUM> inches to about <NUM> inches (e.g., <NUM>-<NUM> inches, <NUM>-<NUM> inches, <NUM>-<NUM> inches, or <NUM>-<NUM> inches, or <NUM>-<NUM> inches). The pitch of the teeth <NUM> and <NUM> is associated with a fineness of control that the user has for locking the position of the driveshaft. In some examples, the pitch of the teeth <NUM> and <NUM> is about <NUM> inches or less (e.g., <NUM> inches, <NUM> inches, <NUM> inches, <NUM> inches, <NUM> inches, <NUM> inches, <NUM> inches, or <NUM> inches or less). In some examples, the pitch of the teeth <NUM> and <NUM> ranges from about <NUM> inches to about <NUM> inches (e.g., <NUM>-<NUM> inches, <NUM>-<NUM> inches, or <NUM>-<NUM> inches).

<FIG> shows the slider lock <NUM> locked in a most proximal position where the slider button <NUM> is against the proximal edge <NUM> of the housing of the handle <NUM>. As shown, the teeth <NUM> of the slider button <NUM> are reengaged with the teeth <NUM> within the housing of the handle <NUM>, thereby locking the axial position of the driveshaft (drive key <NUM> and the hypotube <NUM>) relative to other parts of the catheter system, including the outer shaft. Thus, the slider lock <NUM> allows the user to move the driveshaft with respect to the outer shaft while the driveshaft is rotating, as well as allowing the user to choose an extent to which the driveshaft is translated within and locked with respect to the outer shaft. In addition, the slider button <NUM> allows a selected axial position of the driveshaft to be locked relative to the outer shaft. These features allow the user to select the extent of curvature of the flexible section of the catheter and to lock the flexible section in selected curvature. These features also allow the user to lock the cutter in an active mode (where the cutter extends through the cutter window) or in a passive mode (where the cutter is retracted within the cutter window). For example, having the slider button <NUM> in the distal-most position (e.g., <FIG>) can equate to the cutter being in a passive position and the flexible section of the elongate body in a straight or unbent position. Moving the slider button <NUM> proximally a little from this most-distal position can cause the cutter to pop out of the cutter window. Moving the slider button <NUM> still further proximally can cause the flexible section to bend (e.g., in the s-shape curve) with increasing proximal movement of the slider button <NUM> causing increasing amounts of curvature. Having the slider button <NUM> in the proximal-most position (e.g., <FIG>) can equate to the cutter being in an active position and the flexible section of the elongate body being in a maximally curved position. Moving the slider button <NUM> distally from this most-proximal position can cause the flexible section to decrease in curvature with increasing distal movement of the slider button <NUM> causing decreasing amounts of curvature. Moving the slider button <NUM> still further distally can cause the cutter to retract within the cutter window.

<FIG> also illustrates portions of a saline flushing system of the catheter. The handle <NUM> can include a connector <NUM> that is connected to a tube <NUM> to provide fluid (e.g., saline) within portions of the catheter. Although not shown, the flexible tubing <NUM> can extend (upward in <FIG>) to a connector (e.g., luer connector) that allows the user to directly connect a fluid source (e.g., syringe or saline bag). The fluid can flow through the connector <NUM> to a fluid housing <NUM>, which provides fluidic access between the driveshaft and the outer shaft. The fluid can serve several purposes. For example, the fluid can purge air from the catheter, provide lubrication for the rotational movement of the driveshaft, and can displace blood with an optically transparent fluid (e.g., saline) at a distal end of the catheter so that the imaging system can capture images outside of the catheter while in the blood vessel. In this example, the fluid housing <NUM> includes a distal end <NUM> with a first seal (e.g., O-ring) and a proximal end <NUM> with a second seal (e.g., O-ring) that prevent the fluid from entering other regions of the catheter handle assembly, such as the slider lock <NUM> region of the handle <NUM>.

It should be understood that any features described herein with respect to one embodiment can be combined with or substituted for any feature described herein with respect to another embodiment.

For example, a numeric value may have a value that is +/- <NUM>% of the stated value (or range of values), +/- <NUM>% of the stated value (or range of values), +/- <NUM>% of the stated value (or range of values), +/- <NUM>% of the stated value (or range of values), +/- <NUM>% of the stated value (or range of values), etc. Any numerical range recited herein is intended to include all sub-ranges subsumed therein.

Therefore, the foregoing description is provided primarily for exemplary purposes and should not be interpreted to limit the scope of the invention which is solely set forth in the claims.

Claim 1:
An atherectomy device comprising:
a catheter including a distal nosecone (<NUM>) fixedly coupled to a flexible section (<NUM>) by a bushing (<NUM>, <NUM>) that defines a fixed bend (<NUM>) of the catheter, wherein the catheter includes a cutter window (<NUM>) distal to the fixed bend (<NUM>), wherein the flexible section (<NUM>) includes a longitudinal spine (560a, 560b, 660a, 660b, 960a, 960b, 1160a, or 1160b) on a side of the flexible section (<NUM>); and
a cutter (<NUM>, <NUM>) coupled to a rotatable driveshaft within the catheter,
wherein proximal movement of the cutter (<NUM>, <NUM>) and the rotatable driveshaft causes the cutter (<NUM>, <NUM>) to slide along an edge (<NUM>, <NUM>) of the bushing (<NUM>, <NUM>) to cause the cutter (<NUM>, <NUM>) to tilt in a first direction and to extend through the cutter window (<NUM>),
wherein, when the cutter (<NUM>, <NUM>) is extended through the cutter window (<NUM>), a force applied to the rotatable shaft in a proximal direction places compression on the flexible section (<NUM>) that causes the flexible section (<NUM>) to bend away from the longitudinal spine (560a, 560b, 660a, 660b, 960a, 960b, 1160a, or 1160b) and to take on a curvature, and
wherein distal movement of the cutter (<NUM>, <NUM>) and the rotatable driveshaft causes the cutter (<NUM>, <NUM>) to tilt in a second direction opposite the first direction and to retract within the cutter window (<NUM>).