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: 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 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: 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: 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: 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: A method of removing material from a blood flow lumen generally includes providing a device having a cutting element and an opening, advancing the device through the blood flow lumen to a site where material is to be removed, forcing the opening toward a wall of the site where material is to be removed, and moving the cutting element and the opening so that material in the blood flow lumen is cut by the cutting element and directed into the opening for removal as the cutting element and opening are moved through the blood flow lumen. In some embodiments, the device may be deflected or bent to force the opening toward a wall to remove material. The cutting element may be rotatable and may have an axis that is movable, that is not parallel to the longitudinal axis of the device, or both.

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 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: 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 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: 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: 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.

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: 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: 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: 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.