Abstract: Atherectomy catheters and methods of using them are described herein. In particular, described herein are optical coherence tomography (OCT) catheters that may include a distal tip that can be deflected away from the long axis of the device using a multi-channel bushing. The bushing may include at a hinge point that is offset (e.g., located on a side of the elongate body near the distal end of the elongate body) and a rotatable cutter near an imaging assembly that can be driven against the wall with a high mechanical advantage.

Abstract: An atherectomy catheter includes an elongate flexible catheter body, a cutter near the distal end of the catheter body, a drive shaft connected to the cutter and extending within the catheter body, an imaging element near the distal end of the catheter body and an imaging shaft connected to the imaging element and extending within the catheter body. The cutter and the imaging element are mechanically isolated, and the drive shaft is configured to be axially translated relative to the imaging shaft and the catheter body.

Abstract: Atherectomy catheter devices having a C-shaped balloon opposite a cutting window out of which a rotating cutter may extend and a proximal annular balloon. The C-shaped first balloon may be used to drive the cutter against a vessel and to deploy the cutter by assisting in deflecting a nosecone (distal tip) to expose the distal-facing cutting edge of the cutter. The proximal annular balloon may be used to occlude blood flow. The device may pulled, pushed or rotated in a vessel with the balloons inflated or deflated.

Abstract: An atherectomy catheter includes a deflectable distal tip, a rotatable cutter proximal to the distal tip, a cutter drive shaft configured to rotate the rotatable cutter, and a pull shaft concentric with the drive shaft and coupled to the distal tip. The pull shaft is configured such that pulling the pull shaft deflects the distal tip, thereby exposing the rotatable cutter. Also disclosed herein is a magnetic drive system configured for non-contact actuation of a catheter.

Abstract: An occlusion crossing device includes an outer shaft, an inner shaft, an optical fiber, and a handle attached to the inner shaft and the outer shaft. The inner shaft extends within the outer shaft. The inner shaft includes a drill tip at a distal end thereof. The optical fiber extends within the inner shaft substantially along a central axis of the inner shaft. The distal tip of the optical fiber is attached to the drill tip. The handle is configured to rotate the inner shaft and drill tip at speeds of greater than 500 rpm.

Abstract: Described herein are catheters for use with Optical Coherence Tomography (OCT) that include an optical fiber core having a first refractive index and an interface medium having a second refractive index, where the first and second refractive indexes are mismatched such that receiving electronics configured to receive optical radiation reflected from the reference interface and the target operate in a total noise range that is within 5 dB of the shot noise limit. These OCT catheters may include a silicon die mirror having a reflective coating that is embedded in the interface medium. The optical fiber can be fixed at just the distal end of the catheter, and may be managed within a handle that is attached to the proximal end of the catheter body, and is configured to allow rotation of the both catheter body and the optical fiber relative to the handle.

Abstract: A stylet for re-entry into a vessel includes an elongate body including a proximal portion, a middle curved portion, a pointed distal end, and a longitudinal axis extending through the proximal portion, the middle curved portion, and the pointed distal end. The proximal portion and the middle curved portion have substantially circular cross-sections. The middle curved portion has a pre-shaped curve along the longitudinal axis configured to match a curve of an occlusion-crossing device. The pointed distal end has an s-curve along the longitudinal axis and a flattened portion along the longitudinal axis, the flattened portion having a substantially oblong cross-section.

Abstract: A drive assembly for driving an imaging catheter has a rotatable fiber and a rotatable drive shaft. The drive assembly includes a fiber optic rotating junction and a motor configured to rotate the rotatable portion of the fiber optic rotating junction. In some embodiments, the drive assembly includes a sensor configured to detect a rotational position of the fiber optic rotating junction and a processor configured to obtain the detected rotational position and stop the motor only when the fiber optic rotating junction is in a predetermined rotational position. In some embodiments, the motor includes a hollow shaft through which at least a portion of the fiber optic rotating junction extends.

Abstract: A catheter system includes a catheter body, an imaging sensor, a drive motor, a current sensor, a display, and a controller. The catheter body includes a drive shaft. The imaging sensor is fixed relative to the distal end of the driveshaft and is configured to rotate therewith. The drive motor is configured to rotate the drive shaft. The current sensor is configured to measure an amount of current drawn by the drive motor as the drive shaft is rotated. The display is configured to display one or more images obtained by the imaging sensor as the imaging sensor is rotated. The controller is configured to adjust a rotational orientation of the one or more images displayed by the display based upon the measured current.

Abstract: Described herein is a system and method for identifying elastic lamina during interventional procedures, such as atherectomy. Such identification can be used to avoid trauma to the external elastic lamina during the procedure.

Abstract: Described herein are atherectomy catheters, systems and methods that include a distal tip region that may be moved laterally so that its long axis is parallel with the long axis of the main catheter body axis. Displacing the distal tip region laterally out of the main catheter body axis exposes an annular blade and opens a passageway for cut tissue to enter a storage region within the catheter. The annular blade may be internally coupled to a drive shaft that rotates the blade, and thus the exposed blade edge may have the same crossing profile (OD) as the rest of the distal end region of the catheter. Also described herein are gear-driven atherectomy devices that may use a cable drive shaft to actuate the annular blade. Both push-to-cut and pull-to-cut variations are described, as are methods for cutting tissue and systems including these atherectomy catheters.

Abstract: An occlusion crossing device includes an outer shaft, an inner shaft, an optical fiber, and a handle attached to the inner shaft and the outer shaft. The inner shaft extends within the outer shaft. The inner shaft includes a drill tip at a distal end thereof. The optical fiber extends within the inner shaft substantially along a central axis of the inner shaft. The distal tip of the optical fiber is attached to the drill tip. The handle is configured to rotate the inner shaft and drill tip at speeds of greater than 500 rpm.

Abstract: A catheter device for crossing occlusions includes an elongate catheter shaft, a rotatable tip configured to rotate relative to the elongate catheter shaft, a drive shaft, and an OCT imaging sensor. The rotatable tip includes a housing coupled with the elongate catheter shaft and cutting wedges extendable from the housing. The drive shaft has a central lumen extending therethrough and extends within the elongate catheter shaft. The drive shaft is coupled with the wedges and is configured to rotate the rotatable tip. The OCT sensor includes an optical fiber coupled with the rotatable tip and configured to rotate therewith. The elongate catheter shaft is configured to move axially over the drive shaft to extend and retract the wedges from the housing while maintaining a fixed position of the imaging sensor relative to the cutting wedges.

Abstract: A rotating cutting head catheter for passage through chronic total occlusions or other refractory atherosclerotic plaque from diseased arteries is disclosed. The catheter's rotating cutting head is designed to reside safely within an outer protective sheath when not in use. The outer protective sheath contains one or more helical grooves or slots, and the cutting head contains protruding blades or projections that fit into these helical grooves or slots. Application of torque to an inner catheter or wire attached to the cutting head applies spin to the cutting head, and the force of the sheath's helical grooves or slots against the cutting head's protruding blades or projections advances the cutting head outward from the protective sheath. Once extended, the cutting head may now rotate freely. The device may use a guidewire to direct the cutting head to the desired position.

Abstract: A catheter device for crossing occlusions includes an elongate catheter shaft, a rotatable tip configured to rotate relative to the elongate catheter shaft, a drive shaft, and an OCT imaging sensor. The rotatable tip includes a housing coupled with the elongate catheter shaft and cutting wedges extendable from the housing. The drive shaft has a central lumen extending therethrough and extends within the elongate catheter shaft. The drive shaft is coupled with the wedges and is configured to rotate the rotatable tip. The OCT sensor includes an optical fiber coupled with the rotatable tip and configured to rotate therewith. The elongate catheter shaft is configured to move axially over the drive shaft to extend and retract the wedges from the housing while maintaining a fixed position of the imaging sensor relative to the cutting wedges.

Abstract: An imaging device includes a hollow flexible shaft having a central longitudinal axis and an imaging window therein. An optical fiber extends within the hollow flexible shaft substantially along the central axis. A distal tip of the optical fiber is attached to the hollow flexible shaft and aligned with the imaging window so as to transfer an optical coherence tomography signal through the imaging window. A handle is attached to the hollow flexible shaft configured rotate the hollow flexible shaft at speeds of greater than 1,000 rpm.

Abstract: Described herein are catheters for use with Optical Coherence Tomography (OCT) that include an optical fiber core having a first refractive index and an interface medium having a second refractive index, where the first and second refractive indexes are mismatched such that receiving electronics configured to receive optical radiation reflected from the reference interface and the target operate in a total noise range that is within 5dB of the shot noise limit. These OCT catheters may include a silicon die mirror having a reflective coating that is embedded in the interface medium. The optical fiber can be fixed at just the distal end of the catheter, and may be managed within a handle that is attached to the proximal end of the catheter body, and is configured to allow rotation of both the catheter body and the optical fiber relative to the handle.

Abstract: A catheter for positioning a guidewire across an occluded portion of a vessel includes an elongate catheter body, an integrated rotatable distal tip, a proximal handle region, and a catheter lumen extending through the elongate catheter body. The elongate body has a distal region configured to be bent to a set angle. The integrated rotatable distal tip includes one or more channeled flutes extending around the distal tip that are configured to be rotated in a first direction to dissect tissue and a second direction for bluntly contacting tissue. A proximal handle region includes a control for rotating the distal tip in either the first or second directions. The catheter lumen is configured to pass a guidewire.

Abstract: Atherectomy catheters and methods of using them are described herein. In particular, described herein are optical coherence tomography (OCT) catheters that may include a distal tip that can be deflected away from the long axis of the device using a multi-channel bushing. The bushing may include at a hinge point that is offset (e.g., located on a side of the elongate body near the distal end of the elongate body) and a rotatable cutter near an imaging assembly that can be driven against the wall with a high mechanical advantage.

Abstract: A catheter device for crossing occlusions includes an elongate body, a central lumen extending within the elongate body from the proximal end to the distal end, a rotatable tip at the distal end of the elongate body, and an OCT imaging sensor. The rotatable tip is configured to rotate relative to the elongate body. The OCT imaging sensor includes an optical fiber coupled with the rotatable tip and configured to rotate therewith. A distal end of the elongate body includes one or more markers configured to occlude the OCT imaging sensor as it rotates. A fixed jog in the elongate body proximal to the distal end of the catheter positions the distal end of the catheter at an angle relative to the region of the catheter proximal to the fixed jog and is aligned with the one or more markers on the elongate body.