JP2011517601A - Atherotomy device and method - Google Patents

Abstract

The devices and methods of the present invention generally relate to the treatment of occluded body lumens. Specifically, the devices and methods relate to removal of obstructions from blood vessels and other body lumens. These devices and methods provide a weight loss device with improved means for eliminating obstructions in the body lumen, particularly the vasculature. In many variations, the device is suitable for navigating through tortuous blood vessels. Device and method features allow controlled removal of obstructions and navigation through tortuous and diseased blood vessels.

Description

(Cross-reference of related applications)
This application claims the benefit of US Provisional Patent Application No. 61 / 043,998 (named “Atheology Devices and Methods”, filed Apr. 10, 2008), which is hereby incorporated by reference. .

  This application is also a continuation-in-part of co-pending US patent application Ser. No. 12 / 288,593 (named “Atheteromic Devices and Methods”, filed Oct. 22, 2008), Claims the benefit of patent application No. 60 / 981,735 (named “Atheteromic Devices and Methods”, filed Oct. 22, 2007) and is incorporated herein by reference.

(Field of Invention)
The devices and methods described below generally relate to the treatment of occluded body lumens. Specifically, the devices and methods relate to an improved device for removal of obstructions from blood vessels and other body parts. Such devices include features for improved positioning within a blood vessel that allow for targeted removal of tissue or sweeping of the cutting mechanism in an arcuate path.

  Atherosclerosis is a progressive disease. In this disease, arterial lesions are formed by plaque accumulation and neointimal hyperplasia that cause blood flow disturbances. Often plaques are friable and can be released spontaneously or during endovascular procedures, leading to embolization of downstream blood vessels.

  Endovascular exclusion techniques are well known that reduce or remove obstructions to repair lumen diameter and allow increased blood flow to normal levels. The step of removing the plaque has the effect of removing the diseased tissue and helps the disease to recover. Maintaining the lumen diameter over a period of time (between weeks and weeks) allows the remodeling of blood vessels from a previous pathological state to a more normal state. Ultimately, the goal of endovascular therapy is to prevent short-term complications such as vascular embolization or puncture, and long-term complications such as ischemia from thrombosis or restenosis.

  Various therapies can help achieve the therapeutic goals. In atherectomy, plaque is excised or excised. Various configurations are used, including rotating cylindrical shavers or fluted cutters. The device can include a housing shield for safety. The device may also remove debris by catching debris in the catheter in the downstream filter or by aspirating the debris. In some cases, burrs can be used instead of cutters to grind particularly calcified lesions to very small particle sizes. Aspiration may also be used with a burr-type atherectomy device.

  Balloon angioplasty is another type of endovascular procedure. Balloon angioplasty expands and opens the artery by displacing and compressing the plaque. Balloon angioplasty is known to cause air pressure damage to the blood vessels from the high pressure required to compress the plaque. This trauma leads to an unacceptably severe rate of restenosis. Moreover, this procedure may not be efficient for the treatment of elastic plaque tissue, in which case such tissue may be restored and occlude the lumen.

  When eliminating such an obstruction, it is desirable to protect the vessel wall or body lumen wall from which the obstruction has been eliminated and to reduce the weight of substantially the entire lesion. In additional cases, the procedure of eliminating the obstacles can also be combined with placement of the implant within the lumen. For example, it may be desirable to achieve local drug delivery by deploying a stent to maintain vascular patency over a period of time and / or by eluting the drug or other bioactive agent into the stent.

  Alone, stents cannot function well in the peripheral vasculature for various reasons. Stents with the necessary structural integrity that provide sufficient radial force to reopen the artery often do not work well in the harsh mechanical environment of the peripheral vasculature. For example, the peripheral vasculature encounters significant amounts of compression, twisting, dilation, and bending. Such an environment can lead to stent failure (strut cracking, stent fracture, etc.) that ultimately reduces the stent's ability to maintain lumen diameter over time. On the other hand, stents that can withstand the harsh mechanical aspects of the periphery often do not provide enough radial force to satisfactorily open the blood vessels. In many cases, physicians desire the ability to combine endovascular exclusion procedures with stent placement. Such stenting can be performed before, after, or both before and after the endovascular exclusion procedure.

  Thus, there remains a need for a device that allows an improved atherectomy device that can navigate through tortuous anatomy and exclude material from a body lumen (such as a blood vessel), in which case The device includes features that allow for a safe, efficient and controlled method of scraping or crushing material within a body lumen while minimizing procedure time. In addition, there remains a need for devices that allow navigation of the distal portion of the device while navigating through tortuous anatomy. The ability to steer can assist a physician in accessing tortuous anatomy and can further assist in delivering a guidewire into the inlet of a tilted or tortuous vessel bifurcation / section. . This is possible because the variation of the steered atherectomy catheter described herein can also function as a “shuttle catheter”, in which case the physician will have access to the vessel being accessed. A distal tip can be directed to advance the guidewire from within the catheter into the vessel.

  There also remains a need for a device that is configured to steer but remains in a linear configuration when not articulated. Conventional catheters that embody are generally known to be biased unilaterally, often through repeated articulation or even after being left in the package for a given period of time. Thus, when such a steering feature is combined with a tissue weight loss device, there remains a risk of damage when there is an undesirable bend if the tissue weight loss device should be in a straight configuration.

  The weight loss device described herein is significant to address the above problems and to allow a physician to maneuver the weight loss device through tortuous anatomy and remove tissue at the target site. Provides improved features.

  The devices and methods described herein provide a weight loss device having improved means for eliminating obstructions in body lumens, particularly vasculature. In many variations, the device is suitable for navigating through tortuous blood vessels. Device and method features allow for controlled removal of obstructions and navigation through tortuous and diseased blood vessels. In some variations, the methods and devices also have features that carry the material away from the surgical site without having to remove the device from the body lumen. Additional aspects include controlled tissue removal rates as well as other safety features that prevent accidental cutting of the lumen wall. Although the devices and methods described herein discuss the removal of substances from blood vessels, in some cases the devices and methods also have applicability in other body parts. The device variations and features described below may be incorporated selectively or in combination with a basic device structure that includes a flexible body with a cutter, the cutter comprising a housing and a cutter, the housing Note that and the cutter can rotate relative to each other. Variations include a cutter that rotates within the housing, a housing that rotates around the cutter, and combinations thereof.

  One variation of the devices described herein includes devices that are configured to remove material from body structures. The device is a vascular device and may have the structure and configuration necessary to navigate tortuous anatomy. Alternatively, the device can be a cutter having the desired characteristics when used in other parts of the anatomy.

  In any case, a variation of the device is a catheter body having a proximal end, a distal end, and a catheter lumen extending through the catheter body, a housing, and a housing. A cutting assembly, wherein the cutting assembly is attached to the distal end of the catheter, the housing includes at least one opening, and the cutter includes at least one cutting edge. A sweeping frame positioned adjacent to the cutting assembly, wherein the sweeping frame is connected to the catheter and is rotatable independently of the rotary cutter, the sweeping frame being a compression of the sweeping frame The first radial direction so as to cause a deflection toward the first radial side that results in a deflection of the distal end of the catheter body. A sweep frame having at least one weakening section on the side, the rotation of the deflected sweep frame moving the cutting assembly in an arcuate path relative to the axis of the proximal end of the sweep frame, and the catheter lumen and the sweep frame A rotary torque shaft having a first end extending therethrough and coupled to the rotary cutter and having a second end adapted to couple to the rotary mechanism.

  As described below, the sweep frame can have any number of configurations. However, the sweep frame allows bending of the distal portion of the catheter and rotation of the distal portion of the catheter independent of the torque shaft and rotary cutter. In some variations, the sweep frame rotates independently of the catheter body, and in other variations, the sweep frame rotates with the catheter body. In other variations, the distal portion of the catheter body rotates with the sweep frame while the proximal portion of the catheter body remains stationary. In addition, the device of the present invention can have any number of sweep frames located around the length of the catheter body, where each sweep frame allows bending of the associated section of the catheter. . These sweep frames can be bent and rotated independently of each other. Alternatively, sweep frame bending or rotation can be coupled if so desired.

  The system of the present invention can further include a handle coupled to the proximal end, in which case the sweep frame is rotatable independent of the handle. Typically, the sweep frame is actuated by a sweep member or sweep shaft. The sweep shaft is manufactured so that axial force as well as rotational movement can be translated from the handle or proximal end of the device to the sweep frame.

  In some variations, the sweep frame is configured to limit the deflection of the cutting assembly to a predetermined distance away from the axis of the proximal end of the sweep frame at the maximum angle of deflection. In an additional variation, the bending stiffness and resulting potential apposition force can be varied by the deflected angle or displacement of the cutting assembly and by the axial position along the sweep frame.

  In an additional variation, the weakened section of the sweep frame is a variable column that increases circumferentially away from the first radial side to prevent radial torsion of the sweep frame when deflected. With strength. Such a configuration is intended to prevent twisting or twisting of the weakened section of the sweep frame during bending. In one variation, the sweep frame comprises struts to achieve such selective bending towards the first radial side and an increase in column strength in a direction away from the first radial side.

  In most variations, the sweep frame is located entirely within the catheter body. However, in additional variations, the sweep frame can be exposed or on the exterior of the catheter. In either case, the sweep frame is coupled to the catheter to allow for bending and steering of the catheter.

  The sweep frame structure described herein can be combined with any number of cutting assemblies as described similarly or as is known to those skilled in the art.

  For example, in a variation, the cutter may include a plurality of fluted cutting edges located on both the nearby fluted cutting portion and the distant fluted cutting portion, the fluted cutting portion in the vicinity and the distant fluted cutting portion. The grooved cutting parts are spaced along the cutter axis, and the remote grooved cutting part has fewer grooved cutting edges than the neighboring grooved cutting parts, and when the cutter rotates, The blade removes material from the body lumen.

  The cutting assembly can include a cutting housing having a plurality of openings along an outer surface of the housing. Alternatively, the housing can be a cylindrical housing having an open front. Such an open housing can be rotated (with or in the opposite direction), in which case the housing functions as a cutter. Alternatively, the housing with an open surface can remain stationary.

  In an additional variation of the device, the cutting assembly is a dilator member that extends distally from the front of the housing, extends therethrough, and is in fluid communication with the catheter lumen. A dilator member having a passage can be included, and the dilator member is distant so that as the dilator member is advanced through the material, the dilator member expands the material into the opening of the housing. A tapered shape having a smaller diameter surface at the distal tip and a larger diameter surface adjacent to the front of the housing.

  The present invention also includes a method for reducing obstruction from the body. Such a method includes advancing a catheter having an elongate member with a weight loss assembly attached to the distal end of the elongate member within the body lumen, and a weight reduction assembly adjacent to the obstruction in the body lumen. A positioning step, wherein the weight loss assembly includes a cutter and a bending frame coupled to the distal portion of the catheter and proximate to the weight reduction assembly, the bending frame being reduced to a first radial side of the bending frame. Deflecting the bending frame in a first radial direction by advancing a sweep member at the proximal end of the catheter, comprising: Deflecting the weight reduction assembly also in a first radial direction, and Rotating a torque shaft extending through the catheter and connected to at least the cutter to reduce the obstruction; rotating the bending frame; arcuate relative to the axis of the proximal end of the bending frame; Rotating the sweep member independently of the torque shaft so as to sweep the weight loss assembly in the path.

  As discussed herein, variations of the new device include one or more sweep frames and / or sweep tubes to cause deflection of the distal portion (and other portions) of the weight loss device. The sweep frame improves upon the conventional device to allow the catheter to remain in a linear state when in a linear position. In other words, the sweep frame prevents the weight loss catheter from causing undesirable “bending” when the device is intended to be in a linear position. Such undesirable set bends are common in conventional steered catheters. By avoiding undesired set bends, the weight loss device reduces the possibility of creating unwanted accompanying damage to healthy tissue. For example, a conventional device that makes a bend (due to multiple exposures due to long periods of time in the package after multiple bends) can lean on healthy tissue when the physician assumes that the device is linear . Clearly, activation of a conventional device in such a situation prevents the physician from limiting weight loss to the target site.

  As well as ease of construction (e.g., simple and inexpensive construction), the sweep frame provides excellent column strength due to improved forward cutting speed in linear and deflection positions. This structure has been found to prevent a failure mode in which the sheath collapses onto the torque shaft and wraps the torque shaft in a spiral. The sweep frame also provides superior juxtaposition for better cutting at larger diameters than the catheter.

  In addition, providing a sweep frame that must be compressed in order to deflect allows the configuration to be selectively "tuned" so that the bend portion of the sweep frame has the desired maximum deflection. , The section forming the bent portion interferes mechanically to prevent further bending.

  In another variation, the sweep frame of the device can contain features so that a physician can determine the bending orientation of the device from non-invasive imaging means. For example, a sweep frame or a catheter coupled to the sweep frame can include at least one visualization mark that allows a non-invasive determination of the articulation orientation and direction of the sweep frame. When the visualization mark is deflected, it acts as a radiopaque marker (either a notch or a protrusion) to indicate the direction of the device tip into / out of the fluoroscopic surface, from the bending surface Can be asymmetrically shaped. The marker can also be the addition of stripes / bands / wires, etc. of radiopaque materials such as tantalum, gold, platinum and the like.

  In an additional variation of the method or device, the sweep member can be secured to the device to prevent the bending frame from further bending or returning from bending. It may also be fixed independently of the device to prevent sweeping.

  The device and method also includes delivering fluid through the fluid port. The fluid may contain drugs or other substances to aid in the procedure.

  In another variation of the method for removing tissue in a body passage, the method includes advancing a catheter with a weight reduction assembly attached to the distal end of the catheter in the body, adjacent to the tissue in the body. Locating the weight loss assembly, applying a distal force to the proximal end of the catheter to deflect the bending frame coupled to the distal portion of the catheter, and relative to the axis of the proximal end of the bending frame Rotating the bending frame while deflecting the bending frame to sweep the weight loss assembly in an arcuate path, and torque extending through the catheter and at least coupled to the cutter to remove tissue Rotating the shaft and rotating the bending frame to lose weight in an arcuate path with respect to the axis of the proximal end of the bending frame So as to sweep the assembly may include a step of rotating independently of the sweep shaft and torque shaft.

  Another variation of the method is to advance the catheter to deflect the distal end and cut axially. The axial cutting pattern can be repeated at subsequent radial positions to remove tissue.

  Another variation of the method is to position and deflect a second bend or sweep frame along the catheter body so as to increase the reach of the weight loss assembly so that the weight loss is in the direction set by the first sweep frame. To advance the assembly. The second sweep frame can provide reaction force to the juxtaposed force of the cutter approached against the plaque or tissue without requiring reaction force from the catheter body interacting with the vessel wall. The second bending frame can also be used to allow precise control of the cutter angle with respect to the tissue being reduced. The second sweep shaft can be rotated to sweep the weight loss assembly.

  As described herein, some variations of the device have the ability to articulate. This articulation allows for the manipulation of the device to the target site as well as the generation of a sweep motion for tissue removal. This ability to steer can be useful when trying to navigate a guidewire through tortuous anatomy. For example, physicians often encounter resistance when advancing the guidewire through tortuous anatomy, either due to intravascular occlusions or tortuous vasculature. When the physician encounters such resistance, the guide wire can be withdrawn into or slightly extended from the weight loss catheter. The physician can then maneuver the weight loss catheter to redirect the guidewire for advancement. Once the guidewire is in place, the physician can activate the cutting mechanism to selectively remove tissue.

  The device described herein may have a cutter assembly having a portion of its housing with a curved surface, in which case the cutting edge's as the cutting edge rotates across the opening. The opening forms a plane that intersects the curved surface such that a portion extends out of the housing through the opening. The cutter assembly may also have various other features as described below that improve the safety of the device when articulated during cutting. Moreover, the cutter may have several features that push or propel the cutting tissue into the cutter assembly for final removal by one or more transport members.

  As described, the devices described herein may have one or more transport members that transport substances and / or fluids through the device. Such features are useful for removing cutting tissue and debris from the site during the procedure. In some variations, the device may include multiple conveyors to deliver fluid and remove debris. However, the device of the present invention may also have a container for use in supplementing debris or other material generated during the procedure.

  Another feature for use with the invention herein is the use of a grinding burr that is rotatably coupled to the tip of the device. Burrs can be useful for removing tissue that would otherwise not facilitate cutting by the cutter assembly.

  The devices described herein may use a guide wire for advancement through the body. In such cases, the device has a guidewire lumen located in or around the catheter. Alternatively, a guide wire portion can be attached to a portion of the device.

  The devices of the present invention typically include a torque shaft to deliver rotational motion to the components of the cutter assembly. The torque shaft can include one or more lumens. Alternatively, the torque shaft can be a solid or hollow member. Examples of torque shaft variations also include known aspects of catheter-type devices, such as counter-wound coils, reinforcement members, and the like. In some variations, the torque shaft may have a conveying member that is integrally formed around the outer or inner surface of the shaft. Alternatively or in combination, the conveying member may be disposed on (or in) the torque shaft as described herein.

  As described herein, combinations of the device, system, and method aspects described herein may be combined as needed. Moreover, combinations of devices, systems, and methods themselves are within the scope of this disclosure.

FIG. 1A illustrates an exemplary variation of a device according to the present invention. FIG. 1B shows an exploded view of the device of FIG. 1A. FIG. 1C shows a cross-sectional view of the cutting assembly. FIG. 1D shows an exploded view of the cutting assembly of FIG. 1A. FIG. 2A shows the cutting edge passing through the opening of the housing. FIG. 2B shows a side view of the cutting assembly. FIG. 2C illustrates a positive rake angle. FIG. 3A illustrates a variation having an expansion member. 3B-3D conceptually illustrate the use of a weight loss device having an expansion member. 3B-3D conceptually illustrate the use of a weight loss device having an expansion member. 3B-3D conceptually illustrate the use of a weight loss device having an expansion member. 4A-4B show a variation of a shielded cutter having multiple front cutting edges, rear cutting edges, and fluted cutting edges. 5A-5B show another shielded cutter having a plurality of front cutting edges and fluted cutting edges. 6A-6D show a cutter assembly having an open end housing. 6A-6D show a cutter assembly having an open end housing. 6A-6D show a cutter assembly having an open end housing. 6A-6D show a cutter assembly having an open end housing. FIG. 6E shows an exploded view of the cutter assembly of FIG. 6C. FIG. 6F shows a cutter assembly with an open end housing that removes material from the lumen wall. 6G-6H show respective perspective views and cross-sectional side views of a variation of the open end cutter housing with an inner bevel. 6G-6H show respective perspective views and cross-sectional side views of a variation of the open end cutter housing with an inner bevel. FIG. 7A shows a tissue weight loss device having a sweep frame in an unbent position. FIG. 7B shows the tissue weight loss device of FIG. 7A with the sweep frame bent or compressed to articulate the catheter. 7C-7E illustrate additional variations of the sweep member for use with the weight loss device described herein. 7C-7E illustrate additional variations of the sweep member for use with the weight loss device described herein. 7C-7E illustrate additional variations of the sweep member for use with the weight loss device described herein. Figures 7F-7G show additional possible variations of the catheter body or sweep member. Figures 7F-7G show additional possible variations of the catheter body or sweep member. FIGS. 7H-7I show examples of sweep frame variations with visualization features that allow a physician to determine the orientation and direction of articulation of the cutting assembly when the device is viewed under non-invasive imaging. . FIGS. 7H-7I show examples of sweep frame variations with visualization features that allow a physician to determine the orientation and direction of articulation of the cutting assembly when the device is viewed under non-invasive imaging. . FIG. 8A shows a variation of a device configured for rapid replacement. FIG. 8B illustrates an example of the step of centering the tip of the cutting assembly on the guidewire. FIG. 9A shows the catheter body and the conveyor in the sweep frame. FIG. 9B shows a partial cross-sectional view of a variation of a torque shaft having counter-wound coils. FIG. 9C shows the second conveyor in the torque shaft. FIG. 10A illustrates articulation of the tip of the device. 10B-10D show the sweep of the cutting assembly. 10B-10D show the sweep of the cutting assembly. 10B-10D show the sweep of the cutting assembly. FIG. 11A shows an arrangement of housing windows that prevents damage to the vessel wall. 11B-11C illustrate the arrangement of the cutter assembly features that prevent damage to the vessel wall. 11B-11C illustrate the arrangement of the cutter assembly features that prevent damage to the vessel wall. 12A-12B illustrate a control system for rotating and articulating the cutter assembly. 12A-12B illustrate a control system for rotating and articulating the cutter assembly. FIG. 12C shows a cross-sectional view of a portion of the catheter hub mechanism that removes debris from the device. 12D-12F show examples of variations of the control knob with indexing features. 12D-12F show examples of variations of the control knob with indexing features. FIG. 13 shows a device with a burr tip. 14A-14C provide examples of fluid delivery systems. Figure 3 shows a device placed in a stent or coil. 16A-16B illustrate a variation of the device for removing tissue from a body lumen. Figures 17A-17F illustrate additional variations for centering the device within the lumen. 18A-18C illustrate the use of a weight loss device to assist navigation of a guidewire through tortuous anatomy.

  While the present disclosure is detailed and accurate to enable those skilled in the art to practice the invention, the physical embodiments disclosed herein may be embodied in other specific structures. The invention is merely illustrative. While preferred embodiments have been described, details may be changed without departing from the invention as defined by the claims.

  FIG. 1A illustrates an exemplary variation of a device 100 according to the present invention. As shown, device 100 includes a cutter assembly 102 that is attached to a catheter or catheter body 120. The catheter body 120 can be a reinforced sheath (eg, a polymeric material with a blade). Note that the cutter assembly shown in the figure is for exemplary purposes only. The scope of this disclosure includes combinations of various embodiments, or single elements of various embodiments, and combinations of certain aspects of various embodiments where possible.

  FIG. 1A shows a variation of the tissue removal or weight loss device 100 with the cutter assembly 102 in the housing 104. In this variation, the cutter assembly includes a first set of cutting edges 112 and a second set of cutting edges 109, and the first cutting edges 112 are the full length of the cutting assembly 102 (ie, the housing 104). Extending along the entire length exposed in the opening). In contrast, the second set of cutting edges 109 (in the figure, only one such second cutting edge is visible) extends along only a portion. However, variations of the methods and devices described herein can include any number of cutter configurations as described herein or as known to those skilled in the art. Moreover, although the illustrated device shows a plurality of openings 106 in the housing 104, alternative cutting assemblies can include a housing having a single opening in the distal surface. Such an open face cutter is shown below.

  FIG. 1A also shows the device 100 having a catheter body 120 that extends from a distal portion 122 to a proximal portion (not shown). As discussed below, the catheter body 120 can be coupled to a rotating mechanism or motor 150 that ultimately drives the cutter assembly 102 via the torque shaft 114, as shown in FIG. 1B.

  FIG. 1A further illustrates a variation of the sweep frame 250 located within the catheter body 250. Additional details regarding the various sweep frames are provided below. In any case, the sweep frame 250 causes the distal portion 122 of the catheter 120 to bend or articulate in response to a distally directed force typically applied to the proximal portion of the catheter or the handle of the device. Makes it possible to exercise. For clarity purposes, the sweep frame 250 is shown without the torque shaft 114 extending therethrough. However, the torque shaft extends through the sweep frame 250 and drives the rotation of the rotary cutter 108.

  In the illustrated variation, the sweep frame 250 comprises a tube structure having a plurality of serrated edges, slots, or semicircular openings 252. Overall, the region having the opening 252 of the sweep frame 250 provides a portion of reduced column strength on the first radial side 254 of the sweep frame (i.e., the side containing the opening), The frame 250 is weakened. The portion 256 of the sweep frame 250 that is not weakened maintains a greater column strength than the first radial side 254 of the sweep frame 250. This structure allows deflection of the distal portion of the device when an axial force is applied to the sweep frame 250 and drives it relative to a fixture (eg, a cutter assembly, a portion of the catheter body 120, etc.). As shown in FIG. 1B, this axial force compresses the sweep frame 250 and causes the region with weakened column strength to contract (ie, the side of the sweep frame 250 adjacent to the opening 252 is 1 towards each other on the radial side 254). This in turn causes deflection of the spine or straight side 256 in a direction toward the first radial side 254. Since the sweep frame 250 is coupled to the catheter (completely or partially enclosed within the catheter body 120), the deflection of the sweep frame 250 is in the direction toward the first radial side 254 in the direction of the catheter body and cutter. Deflection of the distal end of the assembly 102 causes the axis of the cutter assembly 102 to form an angle A with the axis of the proximal end 258 of the sweep frame 250.

  The sweep frame 250 can rotate independently of the rotary cutter 108 and the torque shaft 114. In some variations, the sweep frame 250 can rotate independently of the catheter body 120. In such a configuration, as the deflected sweep frame 250 rotates, the cutting assembly and / or distal catheter portion moves in an arcuate path relative to the axis 260 of the proximal end 258 of the sweep frame 250. The sweep frame 250 can also be configured to rotate with the catheter body 120. In this latter configuration, the cutter assembly 102 can also rotate with the sweep frame 250 while the rotary cutter 108 can still rotate independently of the sweep frame 250.

  FIG. 1B also includes a first set of cutting edges 112 that extend along (substantially) the cutter 108 and a second cutting edge 109 that extends along only a portion of the cutter 108. An example of changing the cutting edge is also shown. The number of cutting edges can vary, but typically the cutting edges are symmetrical about the axis 111 of the cutter 108. For example, in one variation, the illustrated cutter 108 includes a pair of second cutting edges 109 positioned symmetrically around the cutter 108 and a pair of first cutting edges positioned symmetrically about the axis 111 of the cutter 108. A blade 112. Accordingly, such a structure provides two cutting edges 112 located on the distal or distal end of cutter 108 and four cutting edges 109 and 112 located near or on the proximal end of cutter 108.

  As shown, the cutter 108 provides a more powerful cutting device by providing fewer cutting edges on the first cutting portion and an increased number of cutting edges on the second cutting portion. . As shown in the figure, the cutter can be configured with cutting edges 109, 112 adjacent to grooves, channels, or flutes (the combination is referred to as "cut flutes"). The flutes provide a path for cutting material to exit the treatment site through the weight loss device. By reducing the number of flutes on the far end of the cutter, the flutes can be made deeper. Deeper flutes allow the cutting edge adjacent to the flutes to remove a greater amount of material. However, increasing the size of the material may also increase the likelihood that the material will become clogged during removal or move slowly through the catheter. To alleviate this potential problem and increase the efficiency of transporting material through the catheter, the cutter can be configured with an increased number of cutting edges towards the back of the cutter, reducing the size of the cutting material. it can.

  FIG. 1B also shows a cutter coupled to the rotating mechanism 150. In this variation, the rotating mechanism is coupled to the cutter via a torque shaft 114 that transmits rotational energy from the rotating mechanism 150 (eg, electricity, air, fluid, gas, or other motor) to the cutter 108. Device variations include the use of a rotation mechanism 150 located generally within the body of the device 100. In one variation, the rotation mechanism 150 may be outside the surgical field (ie, in a non-sterile zone), while a portion of the device (eg, torque shaft, not shown) is outside the surgical field. Extends and connects to a rotating mechanism. The rotation mechanism can be a motor drive unit. In one example, a motor drive unit having 4.5V and capable of producing cutting speeds up to 25Krpm was used. Another embodiment of the motor drive unit included supplying a motor operating at about 12,000 RPM with higher torque at a 6V nominal voltage. This was achieved by changing the gear ratio from 3: 1 to 1: 1.

  The device 100 may also include a vacuum source or pump 152 to assist in evacuating debris generated by operation of the device. Any number of pumps or vacuum sources can be used in combination with the device. For example, a peristaltic pump can be used to drive material from the device into a waste container. FIG. 1B also shows the device 100 coupled to a fluid source 154. Similar to the rotating mechanism, a vacuum source and / or a fluid source can be coupled to a device outside the surgical field.

  It may be advantageous to electromagnetically connect the torque shaft to the drive unit in a rotatable manner without physical contact. For example, the torque shaft 114 can have a magnetic pole installed at the proximal end in a tubular structure attached to a sheath around the torque shaft. The fixed part of the motor can be incorporated in a handle surrounding the tubular structure. This allows continuous suction through the sheath without the use of a high speed rotating seal.

  The device may also include a ferrule 116 as shown in FIG. 1B that allows for coupling of the catheter body 120 to the cutter assembly 102. Ferrule 116 may serve as a seating surface for rotation of cutter 108 within cutter assembly 102. In the illustrated variation, the torque shaft 114 rotates inside the outer catheter body 120, the sweep frame 250, and the ferrule 116 to rotate the cutter and pull or suction tissue debris in the proximal direction. The gap between the catheter tube and the delivery member 118, as well as the pitch and thread depth of the delivery member 118, are selected to provide the desired pump effectiveness.

  In one variation of the device, the housing 104 is connected to the catheter body 120 via a ferrule 116 and is therefore stationary. The cutter 108 rotates relative to the housing 104 so that the cutting edge 112 on the cutter 108 shears or tears the tissue and uses the spiral groove impeller action and the vacuum from the torque shaft in the proximal direction. The tissue inside the housing 104 is captured so that it can be discharged. In alternative variations, such as when the housing includes a front cutting edge, the housing 104 and the cutter rotate. Accordingly, the ferrule can serve as a seating surface for both the housing and the cutter.

  The ferrule can have a distal seating surface for supporting the proximal surface of the cutter 108 to keep the cutter axially stable within the housing 104. When the housing is stationary, the ferrule 116 is firmly bonded / bonded to, crimped or pressed into the housing 104 using solder, brazing, welding, adhesive (epoxy resin), caulking. Can be screwed, snapped, or otherwise attached. As shown, the ferrule 116 can have holes or other rough features that allow it to join with the catheter body. While adhesives and heat fixing can be employed in the assembly, such features are not required. Often the adhesive is not reliable for small surface contact and thermal fusing can degrade the tube. The use of the mechanical locking ring 126 allows the cutting assembly 102 to be shortened. Such a feature is important for maximizing the flexibility of the distal portion of the catheter, as it is required to navigate the meanders in the blood vessel. In one variation, the ring or band (126) can be swaged over the catheter body 120 and over the ferrule 116. This drives the ring / band portions and the catheter body into the ferrule opening, allowing for increased strength between the cutter assembly 102 and the catheter body 120.

  As shown in FIG. 1C, in certain variations, the housing 104 can have a distal protrusion with a central lumen 142 for receiving the mating portion 140 of the cutter 108. Such a feature assists in centering the cutter 104 concentrically within the housing 104. As described below, device variations include burr elements (as shown below) for grinding hard tissue such as calcified plaques, or dilators for separating material towards the opening 106. Includes adding parts.

  The geometry of cutter 108 and housing 104 can be used to adjust the desired degree of cutting. The orientation of the housing 104 and the opening 106 can be used to limit the depth of cutting by the cutter 108. In addition, the distal end of the housing 104 can be dome-shaped while the proximal end can have a cylindrical shape or other shape. For example, by creating a larger window 106 in the housing, a greater portion of the cutter 108 can be exposed and the cutting rate can be increased (for a given rotational speed). By placing the cutting window 106 on the convex or side wall of the housing, the effectiveness of weight loss is more sensitive to the alignment of the cutter housing with respect to the lesion than if the window is on the cylindrical portion of the housing. Further lower. This is a major performance limitation of conventional directional atherectomy catheters. In addition, the placement of the window on the convex portion of the housing creates a secant effect (as described below).

  FIG. 1D illustrates an exploded view of the cutter assembly 102 and the ferrule 116. In this variation, the cutter assembly 102 includes a housing 104 having three openings 106 disposed symmetrically around the sidewall 105 of the housing. FIG. 1D also shows a variation of the cutter 108 with a distal or distal portion 90 mounted on the proximal or proximal portion 92 (where the proximal cutter portion may also be referred to as a cutter core adapter). . The proximal cutter portion 92 includes a shaft 94 that terminates in a mating portion 140 for connecting the cutter 108 to the housing 104 (in which case, the mating portion 140 is within an opening at the front of the housing 104). Nesting). The cutter 108 can also include a passage 96 to allow passage of a guidewire through the device.

  The device of the present invention includes a cutter formed from a single body, but by providing a cutter 108 with distal and proximal cutter portions 90, 92, allows an optimal selection of materials. In addition, as shown, the first cutting edge 112 can extend along both cutter portions 90, 92, while the secondary cutting edge 109 extends only along the neighboring cutter portion 92. Exists. Considering this configuration, when the cutter portions 90, 92 are joined to form the cutter 108, the distal portion 90 of the cutter contains only two grooved cutting edges, while the adjacent cutting portion 92 has four grooves. Includes a cutting edge. Of course, any number of grooved cutting portions is within the scope of the present invention. However, variations include fewer cutting edges on the distal end of the cutter relative to the number of cutting edges on the proximal end of the cutter. Also, the cutting edge may or may not be positioned symmetrically around the cutter.

  2A-6H, illustrated below, illustrate various examples of cutting assemblies that can be incorporated into a steerable tissue removal catheter that uses a sweep frame.

  FIG. 2A illustrates the cutting assembly shown in FIGS. 1A-1D in which the opening 106 forms a helical slot in the housing 104. The opening 106 may or may not be aligned with the cutting edges 109 and 112 of the cutter 108. For powerful cutting, the slot 106 and cutting edges 109, 112 can be aligned to maximize tissue exposure to the cutting edges. In other words, since the cutting edges 109, 112 and the opening 106 can be in a straight line, all the cutting edges 109, 112 are exposed to allow simultaneous cutting. Alternatively, the alignment of the openings and blades 109, 112 may be configured such that fewer than all cutting blades 109, 112 are exposed simultaneously. For example, the alignment may be such that when one cutting edge is exposed by the opening 106, the remaining cutting edge is shielded within the housing 104. Such a configuration variation allows any number of cutting edges to be exposed at a given time. In addition, the variation illustrated in FIG. 2A shows a window or opening 106 that is large enough to expose both the first cutting edge 112 and the second cutting edge 109. However, in alternative variations, the window can be configured to expose only the cutting edge 112 at the distal end of the cutter 108.

  In another variation, to equalize the torque profile of the device when cutting, the number of flutes 110 blades / cutting blades 109, 112 aligned with the housing opening 106 can be used throughout the entire rotation cycle. The cutter 108 can be configured so as not to fluctuate. This prevents the catheter from being overloaded by torque spikes and periodic torque fluctuations due to the multiple cutting edges / flutes that engage the tissue synchronously. In other words, the length of the cutting edge 112 exposed through the opening 106 of the housing 104 remains the same or constant.

  In the variation shown in FIG. 2B, the cutting edges 109, 112 are configured to capture debris within the flutes 110 as the cutter 108 rotates. Typically, the cutter 108 can be designed with a secant effect. This effect allows positive tissue engagement by the cutter 108. As the cutter 108 rotates through the opening, the cutting edge moves in an arc, where the cutting edge protrudes slightly above the plane of the opening at the top of the arc. The amount of positive tissue engagement can be controlled by selection of the protruding distance through appropriate design of the housing geometry (eg, the combination of the location and size of the window and the radius of curvature of the housing) by). The cutting edge 109 or 112 extends out of the housing 104 through the window 106 as it rotates. This structure can also be designed to drive or propel debris on the conveying member 118. In this case, the longitudinal groove 110 in the cutter 108 is provided with a spiral slot so as to remain in fluid communication with the conveying member 118. Variations of the device 100 can also include a vacuum source 152 that is fluidly coupled to the transport member 118. In order to improve the propulsive force generated by the cutter, a variation of the cutter is a spiral groove 110 and sharp parallel to each other and wound proximally to distally in the same direction as the cutter rotation. And a cutting edge 112. As the cutter rotates, it becomes an impeller that moves the tissue debris proximally for ejection.

  As shown in FIG. 2C, a variation of the device can include a cutting edge 109 with a positive rake angle α, that is, the cutting edge is oriented in the same direction as cutter rotation. This structure maximizes the effectiveness of the propulsion and cutting action (by biting into the tissue and avoiding tissue deflection). The cutter is preferably made of a hard wear resistant material, such as a hardened tool or stainless steel, tungsten carbide, cobalt chromium, or titanium alloy, with or without a wear resistant coating as described above. However, any material commonly used for similar surgical applications may be employed for the cutter. The outer surface of the proximal end of the cutter 108 is typically rounded and designed to support the housing 104. Typically, these surfaces should be parallel to the inner surface of the housing. Typically, these surfaces should be parallel to the inner surface of the housing.

  2A-2B also show the surface of the cutter 108 having a pierced profile distally and close to the surface of the housing 104. FIG. Note that the housing opening 106 with this curved profile allows the cutting edge 112 to protrude beyond the outer surface of the housing. In other words, the opening 106 forms a secant on the curved surface of the housing 104. Such a feature allows for improved cutting of harder / harder materials, such as calcified or hard fibrous tissue, where such tissue does not protrude into the housing 104 .

  By controlling the number of cutting edges 109, 112 exposed through the opening 106 in the housing 104, the relative amount of cutting engagement (both controlling the amount of tissue removed per unit revolution of the cutter, It is possible to control both the length and the depth of cutting. These features allow for independent control of the maximum torque load imposed on the device 100. By carefully selecting the flutes and / or the geometry of the cutting edge 112 relative to the housing opening 106, the torque balance can be further controlled. For example, the torque load imposed on the device is caused by tissue shear when the cutter blade is exposed by passing through the housing window. For example, when the number of housing windows is an even multiple of the cutter blade, when all the cutter blades are sheared simultaneously, the torque varies periodically with the rotation of the cutter. Each cycle of the cutter by adjusting the number of cutters and windows so that one is not an even multiple of the other (eg by using five windows on the housing and four cutting edges on the cutter) It is possible to have more uniform torque (exclusion of tissue from shearing action).

  FIG. 3A illustrates a variation of the cutter assembly 102 in which the housing 104 of the assembly 102 includes a conical, tapered, or dilator extension 133 that extends from the front of the housing 104. The dilator extension 133 serves several purposes, i.e., prevents the cutting assembly 102 from damaging the vessel wall. In addition, the added structural reinforcement in front of the housing 104 reduces the likelihood that the rotary cutter 108 will actually cut through the housing 104 when the struts deflect inward. However, one important feature of the dilator extension 133 is that it provides a tapered surface from the guide wire to the opening 106 of the housing 104. Thus, as the dilator extension 133 advances through the obstruction, the dilator extension 133 pushes or expands the material toward the opening 106 and the cutting edge away from the guidewire. In order to expand the material away from the center of the device, the dilator extension 133 must have sufficient radial strength. In one example, the dilator extension 133 and the housing 104 can be manufactured from a single piece of material as discussed herein.

  The dilator extension 133 typically includes an opening 130 for passage of a guide wire. In addition, in most variations, the front end 135 of the dilator extension 133 is rounded to assist in moving the obstruction covering the surface of the dilator 133. Moreover, the surface of the dilator extension 133 can be smooth to allow sweeping of the cutting assembly 102, as will be discussed below. Alternatively, dilator extension 133 can have a number of flutes to direct material into opening 106. In additional variations, the dilator extension 133 may not include the opening 130. In some cases, the dilator extension 133 tapers completely to the closed tip.

  3B through 3D conceptually illustrate the use of a weight loss device having an expansion member 133. In this variation, the device 100 is advanced over the guidewire 128. However, the use of guidewire 128 is optional. As the device 100 approaches the plaque or occlusive material 4, the expansion member 133 pushes the plaque 4 away from the center of the weight loss device 100 and toward the opening 106 of the cutting assembly 102, as shown in FIG. 3C. . Clearly, the expansion member 133 must have sufficient radial strength to push the obstruction toward the opening 106. However, in these variations where the expansion member 133 is conical or tapered, the plaque material 4 is generally moved toward the opening 106. In devices that do not have the expansion member 133, the physician must apply excessive force to move the cutter relative to the plaque 4. In some extreme cases, the cutter actually shears through the housing, leading to device failure. FIG. 3D illustrates the situation where the weight loss device 100 traverses the entire occlusion 4. However, as described below, the device may be configured for sweeping within a blood vessel. As such, the physician may choose to sweep the device 100 within the occlusion to open the occlusion during traversal of the occlusion or after a pathway has been created through the occlusion. In any case, the nature of the expansion member 133 also functions to keep the cutting assembly 102 spaced from the vessel wall 2.

  4A and 4B illustrate additional variations of the cutting assembly 102 for use with various weight loss devices. FIG. 4B shows a side view of the cutter assembly 102 of FIG. 4A. In this example, the cutting assembly 102 includes a larger window 106 that houses a cutter 108 that includes a plurality of directional cutting edges 112, 113, 115. As the cutter 108 rotates within the housing 104, the grooved cutting blade 112 cuts in a direction tangential to the rotation direction of the cutter 108. In other words, the grooved cutting edge 112 cuts the material around the cutter 108 as it rotates. The cutter 108 also includes one or more front and rear cutting edges 113, 115. These cutting edges 113, 115 engage the tissue when the catheter is actuated forward or backward. The ability to engage and disengage in multiple directions has been shown to be important for effective weight loss. However, variations of the cutter 108 of the present invention can include a cutter 108 with one or two directional cutting edges. For example, the grooved cutting edge 112 can be combined with either the front cutting edge 113 or the rear cutting edge 115. The ability to lose weight in the forward, backward, and rotational directions also reduces the likelihood that the cutter assembly will deflect from robust or hard tissue.

  FIGS. 5A and 5B show another variation of the cutter assembly 102 having a front cutting edge 113 at the front of the cutter 108. In this variation, the cutter housing 104 includes two large openings 106 that allow the front cutting edge 113 to engage tissue when moved distally. The cutter 108 also includes a plurality of fluted cutting edges 112.

  6A and 6C illustrate another variation of the cutter assembly 102 in which the housing 104 includes an opening 107 located in front of the cylindrical housing 104. The cylindrical housing 104 contains a cutter 108 therein. In such variations, the front edge of the housing 104 can serve as a front or front cutting edge. As shown, the front cutting edge 113 can be beveled on the outer surface of the housing 104. Such a beveled feature reduces the risk that the cutting edge 113 will circumvent or otherwise damage the vessel wall. As described above, the device, as shown below, will engage and remove the tissue or plaque 4 as it is advanced distally within the body lumen 2. As discussed herein (see FIG. 11A), the features of the device including the guide wire 128 help prevent the device from excessively cutting the lumen wall 2.

  The structure of the cutter 108 can be similar to that shown above. That is, the cutter has various numbers of cutting edges in different parts. Alternatively, the cutter 108 can be a conventional grooved cutter. In one variation, the cutter 108 is tapered or rounded so that the front of the cutter has a rounded or partial spherical shape.

  The housing 104 can be configured to rotate with the cutter 108, or it can function as a stationary, scraping, scooping, or only mold surface. For example, FIGS. 6A and 6B illustrate a variation in which the housing 104 can be attached to the cutter 108 and allows rotation of the entire cutting assembly 102 about a catheter body (not shown) or ferrule 116. In the illustrated embodiment, the cutting assembly 102 includes an adjacent recessed pin cavity 103 to secure the housing 104 to the cutter 108. FIG. 6B shows a cross-sectional view of the cutter assembly 102 of FIG. 6A. As shown, in this particular variation, the entire cutting assembly 102 rotates relative to a ferrule 116 that provides a seating surface for the rotating housing 108. The proximal or proximal portion 92 of the cutter 108 rotates within the ferrule while the proximal end of the housing 104 rotates around the ferrule 116.

  The housing 104 can be linked to the cutter 108 in a variety of ways as is well understood by those skilled in the art. For example, the housing 104 can be linked or attached directly to the cutter 108 via the connection point 103 so that both rotate together. Alternatively, the housing 104 can be interlocked to rotate faster or slower than the cutter 108. In yet another variation, the gearing can be selected to allow the housing 104 to rotate in the opposite direction to the cutter 108.

  A variation of the cutting assembly includes a cutter 108 that partially projects from the front cutting edge 113 of the housing 104. In other variations, the cutter 108 can extend further from the housing 104 and the assembly can comprise a cutter 108 that is fully embedded within the housing 108. In some variations, particularly when a single or double fluted cutting edge configuration is used on the distal portion of the cutter, the cutting edge 113 of the housing 104 is aligned with the deepest depth of the groove on the cutter. Has been identified to enable improved debris rejection.

  In either case, the fluted cutting edge 112 drives the tissue debris back into the catheter. The outer diameter of the housing, proximal to the front cutting edge 113, can be smooth to protect the lumen wall from the cutting action of the cutting edge. When the cutting assembly 102 is deflected, the outer diameter of the housing 102 contacts the lumen wall and prevents the cutting edge from engaging the vessel wall. As the cutter assembly is advanced forward, the plaque 4 protruding from the wall of the lumen 2 is removed and the tissue debris is propelled backwards by the fluted blade 112 of the cutter 108.

  6C and 6D illustrate a variation of the cutting assembly 102 in which the housing 104 of the cutting assembly 102 is stationary around the catheter body (not shown) or ferrule 116 while the cutter 108 rotates within the ferrule. Illustrated.

  FIG. 6D illustrates a partial cross-sectional view of the cutting assembly 102 of FIG. 6C in which the inner portion of the ferrule 116 provides a seating surface for the proximal end 92 of the cutter 108. The housing 104 is attached to the ferrule 116 and may also function as a seating surface for the rotary cutter 108.

  FIG. 6E shows an exploded view of the cutting assembly of FIG. 6C. Again, the cutter 108 can include a distal or distal cutting portion 90 and a proximal or proximal cutting portion 92. The illustrated configuration provides a device having fewer cutting edges 112 on the cutter distal portion 90 and increased cutting edges 109 and 112 on the proximal cutting portion 92. However, variations include conventional grooved cutters. Housing 104 is mounted around cutter portions 90 and 92 and is optionally secured to either the catheter body (not shown) or ferrule 116. As described above, the housing 104 can also be attached to a cutter so as to rotate with the cutter.

  In an alternative variation, the mating surface 140 of the cutter assembly 102 acts as a cushion to prevent accidental cutting into the guidewire or vessel wall given the open distal design of the cutter assembly. It can function as a pointed end shock absorber at the forefront of the cutter 108. In additional variations, the housing 104 can be expandable (such as a basket or net). As cutter 108 pivots inside the housing, the housing expands to cut larger diameters.

  FIG. 6F illustrates the cutting assembly 102 having a front cutting edge 113 at the distal opening 117 of the housing 104. The housing 104 rotates with the cutter 108 to assist in tissue removal. As described above, when the device is advanced distally within the body lumen 2 as shown in FIG. 5E, the front cutting edge 113 engages and removes tissue or plaque 4. As discussed below, the features of the device include the assistance of the guidewire 128 to prevent the device from excessively cutting the lumen wall 2.

  6H and 6I show perspective and cross-sectional side views of another variation of the open end cutter housing 104. FIG. As shown, the cutter housing 104 includes an opening 107 located on the front of the cylindrical housing 104. In this variation, the front edge of the housing 104 can function as a front or front cutting edge and has a beveled surface 177 on the inner surface of the housing 104. Such a graded feature reduces the risk that the cutting edge 113 will drive into the vessel wall. As shown, some variations of the cutter housing 104 include a seating surface 178 located within the housing 104. In additional variations, the distal end or cutting edge 177 of the housing 104 can be fanned or serrated to control the extent to which the cutting assembly removes tissue. For example, instead of being uniform, the cutting edge 177 can vary axially along the circumference of the housing (e.g., the saw blade of the cutter extends along the axial length of the housing). .

  The tissue weight loss catheter described herein performs biopsy, tumor removal, fibroid treatment, unwanted proliferative tissue such as enlarged prostate tissue, or other unwanted tissue weight loss such as disc herniated material Can do. A flexible thin catheter allows for easy access to the treatment site and minimizes trauma or collateral damage to surrounding healthy tissue. The continuous suction capability reduces or even eliminates contamination of surrounding tissue during device introduction, treatment, and removal. In addition, aspiration can be used to transport biopsy tissue samples out of the body for examination while leaving the catheter in place. This helps doctors make real-time decisions when proceeding with malignant tissue treatment. A shield on the cutter assembly maintains a controlled excision of tissue by limiting the depth of cutter engagement, thereby preventing the physician from inadvertently cutting into healthy surrounding tissue. The cutter's tip steering capability allows the physician to direct the cutter toward the desired site of tissue removal, minimizing collateral tissue damage. Finally, by deflecting the cutter and rotating the deflection to sweep the cutter assembly in an arc, the catheter can excise a large tumor or a tissue mass larger than the diameter of the catheter. Thus, resection of large tumors can be accomplished through a small access channel, thereby minimizing trauma to the patient.

  The configuration of the cutting assembly can provide an additional mode of energy delivery. For example, a catheter excises tissue in an angiogenic region where excessive bleeding can occur (eg, lung biopsy and excision). Thus, energy can be delivered to the target site via a conductive cutter assembly (ie, even a shield or cutter). Acoustic energy (ultrasound), electrical energy (radio frequency current), or even microwaves can be used for this purpose. These energy sources delivered through the cutter can also be used to denature tissue (collagen), shrink tissue, or excise tissue.

  A coating can be applied to the moving component of the catheter to reduce friction. In one embodiment, the sheath and torque shaft are coated with a hydrophilic coating (polyvinyl alcohol) to reduce friction between the moving components of the catheter. The coating can also be hydrophobic (eg, parylene, PTFE). The coating can be impregnated with heparin to reduce blood clotting on the surface during use.

  7A through 7E illustrate additional variations of a sweep frame for use with a cutting assembly and catheter as described herein. For the purpose of showing the sweep frame, the torque shaft has been omitted from the drawing. However, as described above in FIG. 1B, the torque shaft extends through the sweep frame, in which case the torque shaft and the sweep frame can rotate independently of each other.

  FIG. 7A is a distal view of the weight loss catheter 100 with the catheter body 120 partially removed to show a variation of the sweep frame 250. In this variation, the sweep frame 250 is comprised of a laser cutting tube or sweep tube having serrated edges, openings, or slots 252. The opening 252 creates a weakened section along the first radial side 254 of the sweep tube 250. The opposite side 256 of the first radial side 254 comprises an area of increased column strength. Thus, when a physician applies an axial force to the proximal end of the catheter 100, typically via a sweep member as discussed below, the force forces the sweep tube 250 against a fixed area within the catheter 100. To compress. As the force compresses the sweep frame 250, the sweep frame 250 is forced to compress in the weakened section along the first radial side 254, and a continuous region of the sweep frame 250 in the direction indicated by arrow 262. Alternatively, bending at the spine 256 is caused. The anchoring zone (the region where the sweep frame encounters resistance) can be the distal zone on the cutter assembly or catheter body 120. However, any area is sufficient as long as the sweep frame 250 can bend when a force is applied.

  The spacing and size of the openings 252 can be selected to allow predetermined bending when the sweep frame 250 is deformed. For example, the opening is selected to limit the deflection of the distal end of the catheter to less than 90 degrees or any angle of bending, thereby providing an additional safety measure when the device is used in a blood vessel can do. Also, the spacing between adjacent openings 252 and / or the size of the openings can vary within the sweep frame 250. For example, the spacing and / or size of the openings 252 can increase or decrease along the length of the sweep frame 250. In additional variations, the spacing and size of the openings can vary in the opposite direction along the length of the sweep frame 250.

  In the illustrated variation, the size of the opening of the sweep tube 250 decreases in a direction away from the first radial side 254 of the sweep tube 250. This configuration has been found to minimize interference with a torque shaft (not shown).

  In addition, the sweep frame 250 described herein can have any number of features to assist in joining the sweep frame 250 to the catheter 100. For example, if the sweep frame is constructed from a superelastic or shape memory alloy, the frame 250 is located on the side wall to increase the bond between the superelastic / shape memory alloy configuration and the regular metal shaft. One or more openings 253 can be included.

  FIG. 7B illustrates the tissue weight loss catheter 100 upon application of the force indicated in the direction of arrow 264. As described above, force 264 is applied to the proximal end or handle of system 100 by a physician. In some variations, the force is applied through the use of a sweep member 270 that is axially movable within the catheter body 120. The sweep member may comprise a tubular structure or spline or wire having sufficient column strength to compress and rotate the sweep frame 250. Because the distal end of the sweep frame is prevented from moving distally (typically because the cutter assembly is attached to the catheter body 120), the sweep frame is spine in the direction of the first radial side 254. Turn in the department. As shown, the spacing of the openings 252 simply decreases on the first radial side 254. This causes articulation of the cutting assembly 102 such that the axis of the cutting assembly is offset from the axis of the proximal end 258 of the sweep frame 250 as represented by angle A. As described herein, angle A is not limited to the angle shown. Instead, the angle can be predetermined depending on the configuration of the particular sweep frame 250 to provide any angle suitable for the target vessel or body lumen.

  In one variation, the sweep member 270 (also referred to as a sweep shaft) can be manufactured as a hypotube tube structure (composed of superelastic alloy or medical grade stainless steel). The sweep member 270 can have varying degrees of flexibility to allow the catheter 100 to be more flexible at the distal portion and rigid at the proximal portion. This allows for improved navigation through tortuous anatomy and improved transmission of torque generated at the proximal end of the device. In an additional variation, the sweep member should not be over-compressed or compressed in view of the need to transmit rotational force to the sweep frame.

  During articulation of the cutting assembly 102, the physician can further rotate the sweep member 270, as indicated by arrow 280. The rotation of the sweep member 270 causes rotation of the sweep frame 250 when articulated, causing movement of the cutting assembly 102 in arcuate motion about the axis of the proximal end of the sweep frame 258. This movement moves the cutting assembly in an arc having a radius represented by 282. In some variations of the device, the sweep frame 250 and the sweep member 270 can rotate independently of the catheter body 120. However, by allowing the catheter body 120 to rotate with the sweep frame 250 and the sweep member 270, the resistance to the sweep member 270 when rotating is reduced. In this latter case, the catheter body 120 and the cutter housing 104 rotate with the sweep frame 250. However, the rotary cutter (and torque shaft, not shown) still rotates independently of the sweep frame 250. Also, as described above, this ability to sweep the cutting assembly 102 with an arc or circle larger than the diameter of the cutter 102 allows the physician to create an opening at the target site that is substantially larger than the diameter of the cutting assembly itself. Make it possible to do. Such a feature eliminates the need to replace the device with a separate cutting tool having a larger cutting head. Such features not only save procedure time, but also allow the device to create a variable size opening in the body lumen.

  FIG. 7B also illustrates a variation of the sweep member 270 that can be applied to any variation of the devices shown herein. In some cases, it may be desirable to disengage the sweep member 270 from the sweep frame 250. In such a case, the sweep member 270 may be slidable in the axial direction to disengage the sweep frame 250. However, upon re-engagement with the sweep frame 250, the sweep member 270 must also be able to rotate the sweep frame 250. Accordingly, the sweep frame 250 and the sweep member 270 can also include one or more keys and keyways. The illustration shows the sweep frame 250 as having a keyway 266 at the proximal end 258 and the sweep member 270 as having a key 272, but any type of configuration that allows translation of rotation can be used. Within the scope of the disclosure.

  FIG. 7C illustrates a variation of the device 100 having a sweep frame 250 with a weakened section 268 having varying column strength. In this variation, the column strength of the sweep frame 250 increases in the circumferential direction away from the first radial side 254. The increase in column strength prevents radial torsion of the sweep frame 250 as it deflects. In the illustrated variation, the sweep frame 250 includes a plurality of reinforcing arms, ribs, or struts 274 within the openings 250 on the sweep frame 250, in which case the arms, ribs, or struts 274 are not included in the sweep frame 250. It is configured to bend preferentially toward the spine 256 as it bends. In this variation, the first radial side adjacent (but spaced) portion containing the arms, ribs, or struts 274 is greater than the radial column strength but the remaining spine portion 256. The second column strength is smaller than the column strength. Again, the varying column strength aims to prevent torsion of the sweep frame 250 during deflection.

  FIG. 7D shows another variation of the sweep frame 250. In this variation, the sweep frame includes a plurality of spaced rings 276 to create openings 252 in the sweep frame 250. The ring can be joined at the spinal region 256 via a separate member, a polymer coating, or a separate frame that is ultimately joined to the ring. As described above, the rings can be spaced apart or resized to achieve the desired predetermined curvature when the sweep frame 250 is compressed.

  FIG. 7E shows that another variation of the sweep frame 250 comprises a woven, coiled, braided, or laser cut network structure similar to a vascular stent. The sweep frame structure can comprise a wire or ribbon material having a reinforced section to function as the spine 256. For example, one side of the stent structure sweep frame 250 can be processed through a covering, fixture, or any other means to increase the column strength of the portion. Accordingly, the region of the stent structure sweep frame 250 functions as the spine portion 256 of the sweep frame 250. Although the spine 256 of FIGS. 7D and 7E is shown along the bottom portion of each sweep frame, the sweep frame may be manufactured to provide a column strength variation region as described above. it can.

  It should be understood that the sweep frame can vary from what has been shown to be any structure that allows selective bending and rotation when placed within the catheter 100. The sweep frame can be made from a variety of materials including shape memory alloys, superelastic alloys, medical grade stainless steel, or other polymeric materials. The material of the sweep frame 250 can be radiopaque or can be modified to be radiopaque. In such a case, the physician can observe the degree of articulation of the device by observing the curvature of the sweep frame 250 before cutting the tissue.

  In general, for proper weight loss of tissue within the blood vessel, the weight loss device should have a catheter that can support the cutter assembly with sufficient apposition force (bending stiffness). The catheter body must be sufficiently torqueable (ie, have sufficient torsional rigidity) so that the physician can direct the cutter to the desired angular position within the vessel. The weight loss device must also be sufficiently pushable (ie, have sufficient column stiffness) to allow proper cutting as the physician advances the device through the tissue. However, these needs must be balanced with creating devices that are too stiff to reliably access tortuous or tilted anatomy. To balance these requirements, the weight loss device variation has a more flexible distal tip location (range within the last 10 cm) to improve navigation within tortuous anatomy. be able to. The overall stiffness (in compression and torque) depends on the total length of the catheter, but since the navigation is mainly affected by this distal tip region, this method can be used to simultaneously optimize several variables. One method.

  An additional design for increased torque and indentation is to build the catheter body and / or sweep member from the blade covering the wound coil by an optional polymer jacket covering. This composite structure may cover a polymer backing made of a material such as PTFE. Yet another variation is a metal tube (e.g., with a selective cut along the length of the tube to produce a desired profile of stiffness (bending, twisting, and compression) along the length of the catheter (e.g. , Stainless steel or Nitinol), and catheter shafts and / or sweep members. This slotted metal tube can be lined or coated with a polymeric material and may be further processed to produce hydrophilic, hydrophobic, or drug binding (heparin, antimicrobial) properties. The configurations described herein apply to any weight loss device described herein.

  7F and 7G illustrate two possible variations of a composite structure that can be employed in manufacturing either a sweep member or a catheter body for use in the weight loss device described herein. Illustrated. FIG. 7F shows a composite structure 290 of slotted tube 292 (where the tube can be selected from polymers, metals such as stainless steel, shape memory alloys such as superelastic nitinol tubes, or combinations thereof). ). The pattern of slots along the tube can be adjusted to achieve desired properties such as graded stiffness along the long and / or short axis of the shaft. The structure 290 can optionally include a polymer coating, sleeve, or backing 298 on the inner and outer surfaces of the tube. FIG. 7F also shows the tube 292 as having a first region 294 and a second region 296 where the frequency of the slots varies from region to region. Any number of slotted tube configurations can be employed in the designs herein, such as those found in medical devices designed for navigation to tortuous areas. Such a design provides significant and unexpected improvements in maneuvering and tissue cutting when incorporated into a weight loss catheter with a sweep frame as described herein.

  FIG. 7G illustrates yet another variation of a composite structure 300 that can be employed with a sweep member and catheter body for use with variations of the weight loss device described herein. As shown, the structure 300 includes a coil member 302 covered by a blade 304. The coils and blades can each be manufactured from any material commonly known in the braid / coiled catheter art. For example, the coil 302 can be wound with a superelastic wire or ribbon. The blade can comprise a plurality of superelastic or stainless steel filaments that are braided or woven together. FIG. 7G also shows a blade 304 covered by a polymer coating, sleeve, or backing 306.

  In an additional variation, the sweep frame and / or the sweep member may comprise a spiral cutting tube covered by a backing or polymer layer. In such cases, the angle and width of the helix can be selected to add the desired properties to the device. For example, when rotating or sweeping the cutting assembly, selecting a helix to maximize the pushability of the device while maintaining an approximately one-to-one relationship between the cutting assembly and the proximal end of the device Can do.

  FIGS. 7H-7I show variations of the sweep frame 250 with visualization features 284 that allow a physician to determine the articulation orientation and direction of the cutting assembly when the device is viewed under non-invasive imaging. An example is shown. FIG. 7H shows a variation of the visualization feature 284 as being a cut or opening on the side of the sweep frame 250 that is perpendicular to the direction in which the frame bends. In one embodiment, the visualization mark is placed at 90 degrees with respect to the spine 256. Although feature 284 is shown on the right side of sweep frame 250, any aspect can be used as long as the location and orientation of feature 284 communicates the orientation and direction of the bend of sweep frame 250 to the physician via non-invasive imaging. May be used. FIG. 7I illustrates another variation of the orientation feature 284 comprising marking material (either a radiopaque additive or a highly radiopaque metal deposited on the sweep frame 250). In any case, the visualization features must provide sufficient contrast for the frame 250 when viewed with non-invasive imaging. The feature may also comprise a structure selected from the group consisting of a cut, an opening, a tab, a protrusion, or a deposit.

  As shown, both visualization features 284 are on the right side of the sweep frame 250 when the spine 256 of the frame 250 is directly adjacent to the physician. In this position, the sweep frame articulation (occurring away from the spine) deflects the sweep frame 250 away from the physician. Thus, when the doctor observes the visualization mark 284 on the right side of the device, the doctor knows that the bending of the sweep frame 250 will occur straight away from the doctor. Obviously, as long as the physician is able to determine the orientation and direction of the sweep frame bend by viewing the visualization mark 284, the present invention can be applied to any number of visualization features, or any part of the sweep frame. Including the placement of such features above.

  FIG. 8A illustrates a variation of device 100 configured for rapid replacement. As shown, device 100 includes a short passage, lumen, or other track 136 for the purpose of advancing device 100 over guidewire 128. However, the track 136 does not extend along the entire length of the device 100. Also, additional portions of the track 136 may be located at the distal end of the catheter so that the guidewire 128 is centered.

  This feature allows for a quick disconnect between the device 100 and the guidewire 128 by simply resting the guidewire and pulling or pushing the catheter 100 over the guidewire. One benefit of such a feature is that the guidewire 128 may remain near the site while being disconnected from the device 100. Thus, the surgeon can quickly advance additional devices over the guidewire to the target. This configuration allows for quick separation of the catheter from the wire and the introduction of another catheter over the wire since the majority of the wire is outside the catheter.

  As shown in FIG. 8B, centering the tip of the cutting assembly 102 on the guide wire 128 improves control, access, and positioning of the cutting assembly 102 relative to the body lumen or vessel 2. To accomplish this, the cutting assembly 102 can have a central lumen for receiving the guidewire 128. Variations on device 100 include a central guidewire lumen that extends the entire length of the catheter through all central components including the torque shaft and cutter. As described above, guidewire 128 can be attached to housing 104 or other non-rotating components of cutting assembly 102. In such cases, guidewire 128 may preferably be a short section that assists in navigation of the device through an obstructed portion of the body lumen. However, since the head is steerable like a guide wire, the device 100 can also operate without a guide wire.

  FIG. 9A illustrates a partial cross-sectional view of a variation of the device 100 showing the placement of the torque shaft 114 within the catheter body 120 and the sweep frame 250. As shown, this variation of device 100 includes a conveyor member 118 located within device 100 and on the outer surface of torque shaft 114. The conveyor member 118 may be an auger type system or an Archimedes type pump that conveys debris and material generated during the procedure away from the surgical site. In any case, the delivery member 118 has a raised surface or blade that pushes the material proximally away from the surgical site. Such material can be delivered to a container outside the body, or such material can be stored within the device 100. In one variation, the torque shaft 114 and the delivery member 118 extend along the length of the catheter. As shown, torque shaft 114 and conveyor 118 fit within sweep frame 250. In some variations of the device, a cover or film between the sweep frame 250 and the torque shaft 114 to prevent debris from being trapped within the serrated edge, slot, or opening 252 of the sweep frame 250. Must be placed. The cover or film also serves as a smooth, low friction surface.

  FIG. 9B shows a partial cross-sectional view of an embodiment of a torque shaft 114 for coupling to a cutter assembly. To assist in material removal, the torque shaft can be a set of counter-wound coils in which the outer coils are wound at a proper (larger) pitch to form the conveying member 118. Torque shaft 114 is reinforced during rotation by automatically winding the coils opposite each other. Alternatively, the torque shaft 114 may be made of rigid plastic and made flexible by incorporating helical undulations or grooves that serve as the conveying member 118. The shaft can be manufactured from any standard material, but variations of the shaft include metal blades embedded in polymers (PEBAX, polyurethane, polyethylene, fluoropolymer, parylene, PEEK, PET), or PEBAX, polyurethane , Polyethylene, fluoropolymer, or one or more metal coils embedded in a polymer such as parylene, polyimide, PEEK, PET. These structures maximize torsional strength and stiffness, as well as column strength for “pushability”, and minimize bending stiffness for flexibility. Such features are important for catheter navigation through tortuous vessels, but allow for smooth transmission over the entire length of the catheter. In a multi-coil structure, the inner coil should be wound in the same way as rotation so that it tends to spread under torque resistance. This ensures that the guidewire lumen remains open during rotation. The next coil should be wound opposite the inner coil to resist expansion, thereby preventing the inner coil from restraining against the outer catheter tube. FIG. 9B also shows a torque shaft 114 having a central lumen 130. Typically, a lumen is used to deliver a guidewire. In such cases, the central lumen may be coated with a lubricious material (such as a hydrophilic coating or parylene) or made of a lubricious material such as PTFE so as to avoid bonding with the guide wire. However, in some variations, the guidewire portion is attached to the distal end of the housing. In addition, the central lumen of the torque shaft 114 may also be used to deliver fluid to the surgical site simultaneously with or instead of the guidewire.

  In some variations, the conveying member 118 is integrated into the shaft 114 (such as by cutting the conveying member 118 into the torque shaft 114 or by extruding the torque shaft 114 directly with a helical recess or protrusion). May be. In an additional variation, as shown in FIG. 9C, an additional carrying member 118 can be incorporated inside the torque shaft, in which case the inner carrying member is wound opposite to the outer carrying member 118. Is done. Such a configuration allows for aspiration of debris (via the external carrier member 118) and injection (via the internal carrier member 118). Such dual effects can be achieved by (1) thinning blood, whether viscosity alone, with the addition of anticoagulants such as heparin or warfarin (coumadin) and / or antiplatelet drugs such as clopidogrel. (2) by converting to a solid-liquid slurry that exhibits higher pump efficiency, by improving the pumping ability (suction) of the excised plaque, and (3) by establishing a local recirculation zone Establishing a fluid-controlled secondary method that captures unembedded emboli directly into the housing can enhance the ability to excise and aspirate plaque.

  As described above, the delivery member 118 can be wound in the same direction as the cutter 108 and in the same rotational direction to achieve suction of tissue debris. The impeller action of the cutter 108 moves tissue debris from the inside of the opening 106 of the housing 104 into the torque shaft. The pitch of the cutting edges 112 can be matched to the slope and pitch of the conveying member 118 to further optimize suction. Alternatively, the pitch of the transport member 118 can be varied to increase the speed at which material moves once it enters the transport member 118. As discussed herein, debris can be caused by the action of the delivery member 118 along the length of the catheter and with or without the complement of a vacuum 152 pump connected to the catheter handle. Can be discharged to the outside. Alternatively, the debris can accumulate in a reservoir within the device.

  FIG. 10A illustrates a variation example of the device 100 being maneuvered when using the sweep frame and sweep member described above. The ability to steer the tip of device 100 is useful under a number of conditions. For example, when reducing eccentric lesions as shown, the cutting assembly 102 should be directed to the side of the blood vessel 2 having a greater amount of stenotic material 4. Naturally, this orientation prevents incision into the bare wall / vessel 2 and concentrates the cutting on the stenotic tissue 4. When in the bend of blood vessel 2, without the ability to steer, cutting assembly 102 tends to bias toward the outside of the bend. As shown in FIG. 10A, the steering allows the cutting assembly 102 to go inward to avoid accidental cutting of the vessel wall 2.

  The ability to steer device 100 also allows for sweeping motion when cutting occlusive material. FIG. 10B illustrates the rotation of the cutting assembly 102. As shown in FIG. 10C, when the cutting assembly 102 deflects with respect to the axis of rotation, rotation of the deflected portion 102 causes a sweep motion. Note that rotation or articulation of the cutting assembly also includes catheter rotation or articulation to allow the cutting assembly to deflect with respect to the catheter axis. FIG. 10D shows a front view taken along the vessel axis to illustrate a sweeping motion that “sweeps” the cutting assembly 102 over an area larger than the diameter of the cutting assembly. In most cases, when articulated, the device is rotated to draw and sweep an arc or even a full circle. The rotation of the cutter can be independent of the rotation of the device. The user of the device may coordinate the sweep motion of the cutting assembly with the axial translation of the catheter for efficient creation of larger diameter openings over the length of the occluded vessel. The combination of movement can be performed when the device is placed over the guidewire, for example, by use of a main screw on the device's proximal handle assembly. In another aspect of the device described herein, the angle of articulation can be fixed so that when rotated, the device sweeps uniformly.

  FIG. 10C also shows a variation of the weight loss device with the catheter body 120, 280, where the first or distal portion 122 of the catheter body rotates as the cutting assembly sweeps in an arc. The second portion 137 of the catheter remains stationary. Thus, a two-part catheter can be joined to allow relative movement between the parts. The second portion 137 may incorporate a sweep frame and a sweep shaft.

  In addition, when the device 100 is substantially aligned with the lesion or engages the lesion below some critical angle of attack, the shape of the housing 104 as well as the location of the window 106 is selected to cut effectively. be able to. However, when pivoted at an angle greater than the critical angle, the cutting edge or grinding element does not engage the lesion, as shown in FIG. 11A. This means that at large deflections, the cutting depth is automatically reduced as the catheter tip approaches the vessel wall and eventually does not cut above the critical angle. For example, the cutter distal tip is rounded and does not cut. As the catheter tip is deflected outward, the pointed tip will contact the blood vessel, preventing the cutting blade proximal to the tip from contacting the vessel wall. Moreover, the wire combined with the device can also serve as a cushioning material and prevent the cutting blade from reaching the blood vessel. As shown, the portion of the guide wire that extends from the housing 104 bends with a minimum bend radius. This prevents the portion of the wire closest to the housing from acting as a shock absorber and the cutter and window from engaging the vessel wall. In some variations, different radii of wire can be selected to provide different degrees of protection by separating the cutting head from the tissue wall.

  11B and 11C show a cutter assembly design that is specialized for forward cutting. This particular variation includes an open end housing (as shown above) with a cutter extending from the housing. However, the pointed round bumper 119 at the tip of the cutter 108 serves as a cushion to prevent accidental cutting into the guide wire 144 or excessively into the lumen wall 2. In addition, this design can optionally incorporate a stationary housing portion 121 on the rear end of the cutter assembly 102 that partially protects the cutter from deep side cutting into the lumen wall 2.

  As shown, the catheter body 120 remains stationary while the inner sweep frame 250 and the sweep member 270 rotate to move the cutting assembly 102 in an arc or trajectory within the lumen. Alternatively, the sweep frame 250 and the sweep member 270 can rotate with the catheter body 120 but independent of the cutting assembly and torque shaft. The outer sheath is preferably sandwiched between polymer matrices of materials such as high density polyethylene (HDPE), polyethylene (PE), fluoropolymer (PTFE), nylon, polyether block amide (PEBAX), polyurethane, and / or silicone. Made of metal blades. The sheath is stiffer proximal than distal. This can be accomplished by using a softer grade polymer at the distal end and / or having no metal blade at the distal end.

  12A and 12B illustrate one variation of a control system or facility. As shown, the control system 200 includes a sweep control knob 202 that is coupled to a sweep member as discussed above. The sweep control knob 202 advances the sweep member in the axial direction to cause the deflection of the sweep frame. In addition, the sweep control knob 202 can rotate independently of the torque shaft and rotary cutter in the cutter assembly 102. Again, the sweep sheath is a metal sandwiched between polymer matrices of materials such as superelastic alloys, medical grade stainless steel, polyethylene (PE), fluoropolymer (PTFE), nylon, and / or polyether block amide (PEBAX). It can be composed of blades, polyurethane, and / or silicone. The sweep sheath can also be made of counter wound metal coils. Its distal end is curved and is preferably made of a material that can withstand a high degree of deflection and retain its curved shape. Such materials may include polymers such as PE, nylon, polyetherketone (PEEK), nickel titanium (Nitinol), or spring steel.

  The sweep sheath is withdrawn proximally by the sweep control knob 202 to allow the cutter assembly to be in the straight undeflected state 102. This causes the removal of the axial force of the sweep frame (in some variations, the sweep frame can be set to a linear configuration). As shown in FIG. 12A, distal movement of the sweep control knob 202 advances the sweep sheath and deflects the catheter tip. The degree of deflection is controlled by the amount by which the sweep sheath is advanced. The axial advance of the sweep sheath is limited by the maximum deflection of the sweep frame.

  As shown in FIG. 12B, the sweep control knob 202 can be rotated to sweep the cutting assembly 102 in an arc. While sweeping of the cutting assembly 102 can occur via manual operation, a variation of the device includes a sweep member that can be selectively coupled to a motor to initiate automatic rotation. This allows the physician to have a smooth and continuous automatic means of sweeping the cutter without manual effort.

  12A and 12B also show the catheter 120 as having an irrigation port 129. The irrigation port 129 is a means for injecting fluid such as heparinized saline or any other drug into the catheter body 120 so that blood and tissue debris do not block the space between the components of the device. I will provide a. The wash port 129 can also serve to lubricate moving components within the device. One desirable fluid path is along the length of the catheter in the space between the catheter body 120 and the sweep member 270. A drug or fluid can be introduced through the irrigation port 129 for outflow from one or more openings 131 near the catheter tip or cutting assembly 102. The drug flowing out near the cutting assembly can then be injected into the vessel wall. The use of stenosis inhibitors such as paclitaxel or rapamycin can help to prevent restenosis after atherectomy procedures.

  Referring now to variations of catheter 100 and control system 200, the entire system, from distal to proximal, cutter assembly 102, catheter body 120, flush port 129, control system 200 for tip deflection and sweep control, cutting A hub 204 or other connection for providing material suction and a drive gear 206 that rotates the torque shaft and cutter are disposed. The gear 206 is connected to a rigid drive shaft 208 that is confined within the hub 204, as shown in FIG. 12C. The drive shaft 208 can take the form of a hollow tube with a central lumen for passage of a guide wire, is centered within the lumen of the hub 204 and is axially secured by a pair of bearings 210. The A seal 211 adjacent to the bearing 210 prevents aspirated tissue debris from leaking proximally through the bearing 210. A transfer propeller 212 is rigidly attached to the distal portion of the drive shaft 208 to deliver the aspirated tissue debris 8 into the aspiration reservoir attached from the catheter. The drive shaft 208 is connected to a flexible torque shaft 114 that extends the length of the catheter body for the purpose of transmitting torque from the drive shaft to the cutter. As described above, torque shaft 114 has a helical groove on its outer diameter and central guidewire lumen. During the procedure, the motor drives the gear 206 to rotate. This causes rotation of drive shaft 208, transfer propeller 212, torque shaft 114, and cutter (not shown), all in the same rotational direction. Thus, the cutter assembly effectively cuts the plaque and drives the debris back into the helical groove on the torque shaft 114. The rotating spiral groove rolls the debris back into the hub 204, which is then transferred by the transfer propeller 212 to the suction reservoir. Propeller 212 may take the form of a screw or a series of circumferentially disposed inclined fan blades. The cutter is preferably rotated at a speed of 10,000 to 25,000 rpm. An alternative design has a suction reservoir built into the catheter hub.

  As described above, when designing the catheter body and / or sweep member, the overall function of the weight loss catheter is improved by selecting desired profiles for bending, twisting, and axial strength characteristics. In addition to improving the ability to advance the cutting assembly and sweep the cutting assembly in an arcuate motion, the preferred characteristics improve the ability of the physician to maneuver the device. For example, selection of suitable characteristics reduces the likelihood that the distal portion of the device will rotate more or less than the proximal end or control knob.

  It has been found that the device of the present invention allows the physician to accurately determine the rotation of the cutting assembly because the rotation of the cutting assembly closely corresponds to the rotation of the proximal end or control knob. Such close correspondence cannot be obtained unless the catheter body and / or sweep member has sufficient bending, twisting, and axial strength characteristics. Thus, when these catheter bodies / sweep members are coupled to a system having a sweep control knob 202 that allows indexing and monitoring of the orientation of the cutter assembly, additional aspects of the weight loss device arise. Clearly, this one-to-one relationship can be lost when the distal end or cutting assembly encounters sufficient resistance against or inside the lesion, occlusion, or diseased tissue. However, in such cases, the device can still lose tissue and perform its function even though the response may not be one-to-one. In any case, the ability to maintain a substantially one-to-one relationship and minimize rotational misalignment between the ends of the device allows the weight loss device to be steered toward the treatment site.

  FIG. 12D shows a conceptual diagram of a control knob 202 that allows indexing of the cutting assembly. As shown, the control knob 200 includes an orientation marker 214 that corresponds to a weakened section of a sweep frame (not shown). As discussed above, the orientation marker 214 also corresponds to the side of the sweep frame that is opposite the spine portion of the sweep frame. Because the orientation marker 214 is aligned with the sweep frame in such a manner, the physician knows that the device bends in the direction corresponding to the orientation marker 214. This allows the physician to identify the orientation of the cutting assembly as it sweeps through the body by observing the orientation of the orientation marker as the sweep control knob 202 rotates. Even when the one-to-one relationship is lost (as described above), the indexed knob directs the distal end in defined steps or increments with minor adjustments. This control can be useful because the physician can direct the cutter in close proximity to operate on the area that needs to be cut, compared to losing position due to excessive movement. An atherectomy or tissue weight loss device with features that allow for indentation and torsional strength allows physicians better feedback and control when attempting to steer the cutting assembly toward the desired path in the body To do.

  The sweep control knob 202 can include a plurality of indexing stops or indentations 216. Although this device variation contains indentations, these indexing stops 216 can have twice the benefit. First, they allow incremental rotation indexing as the physician rotates the knob 202. Incremental indexing is enabled by device bending, twisting, and axial strength properties that allow little or no misalignment between the edges of the device. A secondary advantage of the indexing stop 216 is that the physician can bend the distal end of the weight loss catheter by advancing the knob 202 in the axial direction and moving the sweep member 270 in the axially distal direction, or To allow incremental axial indexing when maneuvering.

  As shown, any number of positions 218, 220, 222, 224 can be created on the knob 202. As shown in FIG. 12E, the spring pin 226 can provide tactile feedback to the physician as the knob 202 rotates. By moving the knob 202 in the axial direction 228, once the physician desires to bend or steer the weight loss device, the physician may configure the second stop 220 and the third stop as shown in FIG. 12F. The movement of the knob into 222 is felt.

  Additional components can be incorporated into the devices described herein. For example, it may be desirable to incorporate a transducer in the distal region of the catheter to characterize plaque or to evaluate plaque and wall thickness and vessel diameter for treatment planning. For example, a pressure sensor placed on a catheter housing can sense the increase in contact force encountered when the housing is pressed against the vessel wall. The temperature sensor can be used to detect vulnerable plaque. The ultrasonic transducer can be used to assume lumen area, plaque thickness or volume, and wall thickness. Optical coherence tomography can be used to make plaque and wall thickness measurements. The electrodes can be used to detect the impedance of the contact tissue, allowing differentiation of plaque and vessel wall types. The electrodes are also used to deliver impulses of energy, for example to assess innervation, either stimulate or inactivate smooth muscle, or characterize plaque (composition, thickness, etc.) You can also. For example, transient convulsions can be introduced to help guide blood vessels to smaller diameters and then be restored either by electrical or pharmaceutical means. Electrical energy can also be introduced to improve the delivery of drugs or biological agents by opening cell membranes in response to electrical stimulation (electroporation). One method of characterization by electrical measurement is electrical impedance tomography.

  As shown in FIG. 13, the cutter assembly 102 can also have burrs protruding from its protrusions. The burr 180 may have any type of wear surface, but in one variation, the burr is rounded to allow for the crushing of severe calcified tissue without damaging adjacent soft tissue. Has fine sand grains (diamond sand grains, etc.). While this combination of burr and cutter allows the distal assembly to remove hard stenotic tissue (calcified plaque) using a burr, the sharp-cutting cutter of the blade can be used for fibrous tissue, adipose tissue, smooth Remove softer tissues such as muscle growth or thrombus. In variations, the burr can also have a spiral flutes to aid in suction, or a burr can be incorporated into a portion of the cutting edge (eg, the most distal surface of the cutter).

  Injecting a solution (cleaning fluid) into the target treatment site may be desirable. Injected cold saline can prevent heating of blood and other tissues, which reduces the possibility of thrombus or other tissue damage. Heparinized saline can also prevent blood clots and thin blood to help maximize the effectiveness of aspiration. The lavage fluid can also include agents such as clopidogrel, rapamycin, paclitaxel, or other restenosis inhibitors. This can help prevent restenosis and can provide better long-term patency. The lavage fluid may include a paralytic or long-acting smooth muscle relaxant to prevent severe vessel recoil. 14A-14C illustrate a variation of the outflow from the device 100. FIG. Lavage fluid is injected through the guidewire lumen (FIG. 14A), the side lumen of the catheter shaft or tube (FIG. 14B), the space between the bending sheath and the catheter, and / or the side port of the guidewire (FIG. 14C). be able to. The irrigation fluid can exit a port at the distal end of the cutter that facilitates aspirating the irrigation solution proximally. Alternatively, flow can be directed backwards by the Coanda effect by leaching the cleaning fluid from the distal end of the cutter housing over the curved surface. Restenosis inhibitors are carried by tissue adhesives or microcapsules with velcro-like features on the surface to adhere to the inner surface of the blood vessel, so that the drug adheres to the treatment site and by reabsorption or dissolution of the membrane Providing controlled sustained release can further improve efficacy. Such Velcro-like features can be constituted by nanoscale structures made of organic or inorganic materials. Any of these techniques can be made more effective by reducing the amount of foreign material and exposing the remaining tissue and extracellular matrix to drugs, stimuli, or sensors.

  Another method of injecting fluid is to supply pressurized fluid at the proximal portion of the guidewire lumen, eg, an intravenous bag (gravity or pumping). A hemostatic seal with a side branch is useful for this purpose, and the Tuohy-Borst adapter is one example of a means of implementing it.

  By balancing the relative amount of infusion with the amount of fluid aspirated, it is possible to control the vessel diameter. Aspiration of more fluid than is soaked empties the vessel and reduces its diameter, allowing cutting of lesions at a larger diameter than the atherectomy catheter. This is a problem for certain open cutter designs that use suction, as the aggressive suction required to catch the embolic particles will empty and collapse the arteries around the cutter blade. Yes. This is both a performance issue because the cutter can become stuck with too high a torsional load and the cutter can easily pierce blood vessels. The shielded design described herein obviates both problems, further requires that less aggressive suction be effective, and gives the user more extensive control.

  The device of the present invention may also be used in conjunction with other structures placed within a body lumen. For example, as shown in FIG. 15, one method of protecting blood vessels and allowing maximum plaque weight loss is to deploy a protective structure such as a stent, thin expandable coil, or expandable mesh 182 within the lesion. It is to be. As this structure expands after deployment, the thin wire coil or strut pushes radially outward through the plaque until it is substantially flush with the vessel wall. This expansion of the thin member requires minimal displacement of the plaque volume and minimizes the barometric trauma that occurs during balloon angioplasty or balloon expansion stent delivery. When the protective structure is fully expanded, an atherectomy can be performed to cut the inner plaque and widen the lumen. Because the structural member (coil or strut) is placed in a manner that resists cutting by the atherectomy cutter and cannot be inserted into the cutter housing (and thus cannot be grasped by the cutter), the vessel wall has expanded Protected by structure. It is also possible to adjust the angle of the window on the atherectomy catheter cutter housing so that it does not align with the struts or coils. Orientation adjustment can be done by coil or strut design, cutter housing design, or both. In addition, the protective member may be left in place as a stent because it is relatively flexible and can have a thin profile (thin element). In this case, the stent repairs lumen patency primarily depending on atherectomy, so it can be designed to exert even less radial force when deployed. This allows the use of a wider range of materials, such as bioresorbable polymers and metal alloys, some of which may not have high stiffness and strength. This also allows for a more elastic design that is sensitive to mechanical forces in the peripheral arteries. It also minimizes flow disruption and minimizes hematogenous disorders such as thrombosis associated with the relatively low flow rates seen in the periphery. Regardless of whether or not atherectomy is used after placing the structure, it is also possible to perform atherectomy before placing the protective structure.

  An additional variation of the system includes a device 100 having a cutting assembly 170 that includes a rotating turbine-like coring cutter 172 as shown above and as shown in FIG. 16A. FIG. 16B shows a side view of the coring cutter 170. In use, the coring cutter can be hydraulically pushed to drive a sharp blade through the tissue. The turbine-like cutter has a spiral blade 174 inside a sharp cylinder housing 176 (outer structure). The coring cutter 170 may also center the shell structure near the guidewire by having a spoke or centering device 184 as shown in FIGS. 17A-17F. This helps to keep the plaque cutting center near the vessel wall for safety. The spoke also acts as an impeller to retract the stenotic tissue, which helps drive the cutter forward and achieve aspiration to minimize emboli.

  Use the devices and methods described herein to repair patency to arterial lesions in coronary and cerebral circulation, both by reducing new lesions and reducing stent restenosis It is also possible.

  The devices and methods described herein are also difficult to treat otherwise in bifurcations, tortuous arteries, and in arteries subjected to biomechanical stress (such as in knees or other joints). It is particularly successful in lesions.

  In a further variation of the device described herein, the motor drive unit is powered by a controller that varies the speed and torque supplied to the catheter, thereby securing the fixed flexible distal of the catheter. Use variable speed with length (or provide additional trajectory control by controlling the length of the distal flexible section of the catheter) to optimize cutting efficiency or automate the cutter Can be on track.

  By using feedback control to operate the catheter in vascular safety mode, the cutting speed can be reduced as the vessel wall is approached. This can be achieved through speed control or by reducing the extent to which the cutting blade penetrates above the housing window by retracting the cutter axially within the housing. The feedback variable can be by light (infrared) or ultrasonic transducer, or by other transducers (pressure, electrical impedance, etc.) or by monitoring motor performance. The feedback variable can also be used in a safety algorithm, for example, to stop the cutter in a torque overload situation.

  The atherectomy catheter may further be configured with a balloon proximal to the cutter for auxiliary angioplasty or stent delivery. The catheter can optionally be configured to deliver a self-expanding stent. This provides convenience to the user and provides further certainty of the adjunct therapy at the intended location where the atherectomy is performed.

  Further methods include the use of similar devices to reduce stenosis at the AV hemodialysis access sites (fistulas and vascular grafts) and to remove thrombus. A suitable non-cutting thrombectomy catheter can be constructed by removing the cutter housing and embedding a fluted cutter within the catheter sheath.

  Other methods of use include excising bone, cartilage, connective tissue, or muscle during minimally invasive surgical procedures. For example, a catheter that includes a cutting and burr element may be used to gain access to the spine to perform a laminectomy or spine arthrotomy procedure to relieve spinal stenosis. For this application, the catheter is further designed to be deployed through a rigid cannula over a portion of its length, or has a rigid portion on its own to aid in surgical insertion and navigation. obtain.

  It is advantageous to combine atherectomy with stenting. By removing material and reducing the lesion, smaller radial forces are required to further open the artery and maintain the lumen diameter. The amount of weight loss can be adjusted to better coordinate with the mechanical properties of the selected stent. For stents that deliver even greater expansion and radial forces, relatively little atherectomy is required for satisfactory results. An alternative treatment method is to significantly reduce the lesion, which allows for optimized stent placement for the mechanical conditions inherent in the peripheral anatomy. In essence, the stent supports itself against the vessel wall and provides a gentle radial force to maintain lumen patency. Stents can be bioresorbable and / or drug eluting, where resorption or dissolution occurs over a period of several days up to 12 weeks or more. The period of 4 to 12 weeks is the time course of remodeling and return to stability, as seen in typical wound healing responses, in particular the time course of arterial remodeling after the stent procedure. Matches well. In addition, the stent geometry can be optimized to minimize thrombosis by inducing vortex flow. This has the effect of minimizing or eliminating stagnation or recirculation flow that leads to thrombus formation. The helical structure of at least the proximal (upstream) portion of the stent accomplishes this. It is also beneficial to ensure that the flow rate directly distal to the stent does not create a stagnation or recirculation zone, and vortexing is also a way to prevent this.

  Any of the atherectomy devices 100 described herein can be used as a tool to treat chronic total occlusion (CTO) or complete blockage of an artery. Forward cutting and tip steering capabilities allow the physician to controllably create a channel through the obstruction. In one such method (recanalization) for creating this channel, the physician places the device 100 on the proximal edge of the obstruction 10. The following application contains additional details about such devices, as well as additional features of various weight loss devices that are useful in treating CTO. Such patent applications are filed on Oct. 19, 2006, U.S. Patent Application No. 11 / 551,191, U.S. Patent Application No. 11 / 551,193, U.S. Patent Application No. 11 / 551,198, respectively. U.S. Patent Application No. 11 / 551,203, U.S. Patent Application No. 11 / 567,715 filed on December 6, 2006, U.S. Patent Application No. 11/771 filed on June 29, 2007. , 865, U.S. Provisional Application No. 60 / 981,735, filed Oct. 22, 2007, each incorporated by reference.

  In another variation of the present invention, the steerable weight loss device 100 improves the physician's attempt to navigate the guidewire 144 through a branched anatomy, tortuous anatomy, or otherwise occluded anatomy. Can do. In the variation shown in FIG. 18A, when the physician navigates the guidewire 144 through the anatomy, the tortuous nature of the anatomy or the obstruction 4 in the blood vessel 2 prevents the advancement of the guidewire 144 as shown. There is a case. In such cases, the steerable weight loss device 100 of the present invention allows a physician to withdraw the guidewire into or just distal to the weight loss device 100 (as shown in FIG. 18B). ). The device 100 is then advanced to the bifurcation point or beyond the tortuous location and articulated so that the physician bends the guidewire 144 over the obstacle to an acute angle or into the desired bifurcation. Can be advanced (as shown in FIG. 18C).

  It should be noted that the above description is intended to provide exemplary embodiments of devices and methods. It is understood that the present invention includes combinations of aspects of the embodiments or combinations of the embodiments themselves. Such variations and combinations are within the scope of this disclosure.

  The foregoing is merely considered as illustrative of the principles of the present invention. Moreover, since numerous modifications and changes will readily occur to those skilled in the art, it is not desired to limit the invention to the exact construction and operation shown and described. While preferred embodiments have been described, details may be changed without departing from the invention as defined by the claims.

Claims (69)

A catheter body having a proximal end, a distal end, and a catheter lumen extending through the catheter body;
A cutting assembly including a housing and a rotary cutter positioned within the housing, the cutting assembly being attached to the distal end of the catheter, the housing including at least one opening; The cutter includes a cutting assembly including at least one cutting edge;
A sweep frame positioned adjacent to the cutting assembly, wherein the sweep frame is coupled to the catheter and is rotatable independently of the rotary cutter, the sweep frame being a first radial side Providing at least one weakened section to cause the compression of the sweep frame to cause a deflection toward the first radial side that results in deflection of the distal end of the catheter body, the deflection of the swept sweep frame A sweep frame that moves the cutting assembly in an arcuate path relative to the axis of the proximal end of the sweep frame;
A rotary torque shaft extending through the catheter lumen and a sweep frame, the rotary torque shaft being adapted to connect to a first end connected to the rotary cutter and to a rotary mechanism; And a rotary torque shaft having a second end.   The tissue weight loss device of claim 1, wherein the weakened section on the first radial side comprises reduced column strength.   The catheter further comprises at least one second sweep frame located within the catheter body so that the first sweep frame and the second sweep frame can be deflected independently of each other. The tissue weight loss device of claim 1, wherein the compartment is bent.   The tissue weight loss device of claim 1, wherein the catheter body further comprises a handle coupled to the proximal end, and the sweep frame is rotatable independent of the handle.   The tissue weight loss device of claim 1, wherein the sweep frame comprises a tube structure, the tube structure being elastically deformable to deflect toward the first radial side.   6. The tissue weight loss device of claim 5, wherein the tubular structure comprises at least one semicircular opening.   The tissue weight loss device of claim 6, wherein when the tube structure is deflected, a plurality of tube sections between adjacent openings interfere to cause the tube to be rigid upon deflection.   The tissue of claim 6, further comprising a plurality of ribs in each opening, the ribs connecting adjacent portions of the tubular structure to provide torsional stability and flexibility to the tubular structure. Weight loss device.   7. The tissue weight loss device of claim 6, wherein the semicircular opening is maximal on an opposite side of the first radial side.   The semicircular opening is selected to have a length that limits deflection of the cutting assembly to a predetermined distance away from the axis of the proximal end of the sweep frame. Tissue weight loss device as described in.   The sweep frame includes a plurality of rings attached to and spaced apart from a spine, the spine being located opposite the first radial side. Tissue weight loss device.   The tissue weight loss device of claim 1, wherein the sweep frame comprises a mesh structure having a reinforcing section on an opposite side of the first radial side.   The tissue weight loss device of claim 1, wherein the sweep frame comprises a coiled structure made of ribbon having a reinforcing section opposite the first radial side.   14. The tissue weight loss device of claim 13, wherein the reinforcing section is a spine made of ribbon.   The tissue weight loss device of claim 1, wherein the sweep frame is configured to limit deflection of the cutting assembly to a predetermined distance away from the axis of the proximal end of the sweep frame.   The tissue weight loss device of claim 15, wherein the predetermined distance is selected based on a target vessel.   The weakened section of the sweep frame has a variable column strength that increases circumferentially in a direction away from the first radial side to prevent radial torsion of the sweep frame when deflected The tissue weight loss device of claim 1.   Each portion of the sweep frame that is radially adjacent to the first radial side is greater than the column strength on the radial side, but less than the third column strength of the remaining sweep frame, a second 18. The tissue weight loss device of claim 17, comprising column strength, wherein such second column strength prevents twisting of the sweep frame when deflected.   The tissue weight loss device of claim 1, further comprising a sweep member that is axially movable within the catheter.   20. The tissue weight loss device of claim 19, wherein the sweep member is releasably securable to the catheter to prevent the sweep frame from bending or returning from bending.   21. The tissue weight loss device of claim 20, wherein the sweep member and sweep frame comprise one or more keys or mating keyways.   20. The tissue weight loss device of claim 19, wherein the sweep member comprises a sweep shaft having at least two regions, each region comprising a different flexibility.   20. The tissue weight loss device of claim 19, wherein the sweep member is removably engaged with the proximal end of the sweep frame.   The tissue weight loss device of claim 1, wherein the sweep frame is generally located within the catheter body.   25. The tissue weight loss device of claim 24, wherein the sweep frame and catheter body rotate together.   25. The tissue weight loss device of claim 24, wherein the sweep frame is independently rotatable within the catheter body.   25. The tissue weight loss device of claim 24, wherein the first portion of the catheter body rotates with the sweep frame while the second portion of the catheter body remains stationary.   The tissue weight loss device of claim 1, wherein the sweep frame is radiopaque.   The tissue weight loss device of claim 1, wherein the sweep frame comprises at least one visualization mark that allows non-invasive determination of the articulation orientation and direction of the sweep frame.   30. The tissue weight loss device of claim 29, wherein the visualization mark comprises a structure selected from the group consisting of a notch, an opening, a tab, a protrusion, or a deposit in the sweep frame.   30. The tissue weight loss device of claim 29, wherein the visualization mark comprises a region that provides sufficient radiopacity contrast to the remainder of the sweep frame.   30. The tissue weight loss device of claim 29, wherein the visualization mark is disposed at 90 degrees relative to the first radial side.   The tissue weight loss device of claim 1, wherein the sweep frame comprises a material selected from a polymer, a shape memory alloy, a metal alloy.   The tissue weight loss device of claim 1, wherein the elongate body is flexible enough to navigate through tortuous anatomy.   The cutter includes a plurality of fluted cutting edges located on both a nearby fluted cutting portion and a distant fluted cutting portion, the grooving cutting portion in the vicinity and the distant grooving cutting portion comprising: Spaced apart along the axis of the cutter, the distant grooved cutting portion has fewer grooved cutting edges than the adjacent grooved cutting portion, and the grooved cutting blade is rotated when the cutter rotates. The tissue weight loss device of claim 1, wherein the material removes material from the body lumen.   The tissue weight loss device of claim 1, wherein the torque shaft includes an outer surface thereon having a helically located raised portion so that when rotated, the raised portion carries material proximally.   The distant cutting portion comprises two distant grooved cutting edges that are positioned symmetrically about the axis, and the adjacent cutting portion includes four adjacent grooved cutting edges that are positioned symmetrically about the axis. The tissue weight loss device of claim 1, comprising a blade.   The at least one opening includes a plurality of openings, and the cutter is positioned in the casing, whereby the grooved cutting blade passes through the openings of the casing when the cutter rotates. The tissue weight loss device of claim 1, wherein the device is cut.   2. The housing of claim 1, wherein the housing comprises a cylindrical housing having an open front, the edge of the side wall of the cylindrical housing comprises a front cutting edge, and the cutter rotates within the cylindrical housing. The described tissue weight loss device.   40. The tissue weight loss device of claim 39, wherein the front cutting edge is beveled.   40. The tissue weight loss device of claim 39, wherein the cylindrical housing is fixed relative to the cutter.   40. The tissue weight loss device of claim 39, wherein the cylindrical housing rotates with a cutter.   40. The tissue weight loss device of claim 39, wherein the cylindrical housing rotates in a direction opposite to the cutter.   A dilator member extending distally from the front of the housing, the dilator member having a passage extending therethrough and in fluid communication with the catheter lumen; The dilator member comprises a tapered shape having a smaller diameter surface at the distal tip and a larger diameter surface adjacent to the front of the housing so that the dilator member passes through the substance. The tissue weight loss device of claim 1, wherein the dilator member expands material into the opening in the housing as it advances. A method for reducing occlusions in a fully or partially occluded body lumen comprising:
Advancing a catheter having an elongate member within the body lumen with a weight loss assembly attached to a distal end of the elongate member;
Positioning the weight loss assembly adjacent to the obstruction within the body lumen, the weight loss assembly coupled to a cutter and a distal portion of the catheter and a bending frame proximate to the weight loss assembly The bending frame comprises at least a section having reduced column strength on a first radial side of the bending frame;
Deflecting the bending frame in the first radial direction by advancing a sweep member at the proximal end of the catheter, wherein deflecting the bending frame comprises: Deflecting the weight loss assembly also in a radial direction;
Rotating a torque shaft extending through the catheter and coupled to at least the cutter to reduce the obstruction;
Reducing the occluding material while the axis of the weight loss assembly forms an angle with the axis of the proximal end of the bending frame.   Further comprising rotating the sweep member independently of the torque shaft, thereby rotating the bending frame in an arcuate path relative to the axis at the proximal end of the bending frame. 46. The method of claim 45, wherein the is swept.   47. The method of claim 46, further comprising securing the sweep member relative to the catheter, thereby preventing the bending frame from further bending or returning from bending.   48. The method of claim 46, wherein rotating the sweep member includes rotating the sweep member independent of the elongated body of the catheter.   48. The method of claim 46, wherein rotating the sweep member includes rotating the sweep member with an elongated portion of the catheter.   46. The method of claim 45, further comprising translating the weight loss assembly parallel to the axis of the proximal end of the bending frame to remove tissue.   46. The method of claim 45, further comprising axially translating the weight loss assembly within the blood vessel.   46. The method of claim 45, further comprising coupling a proximal end of the elongate member to a handle member, wherein rotating the sweep member includes rotating the sweep member independent of the handle member. Method.   46. The method of claim 45, wherein a distal portion of the weight loss assembly includes at least one fluid port coupled to a fluid source and further includes delivering fluid through the fluid port.   46. The method of claim 45, wherein delivering a fluid comprises delivering a drug through the fluid port.   46. The method of claim 45, further comprising providing a helical conveyor member within the weight loss device and transporting debris material out of the body via the helical conveyor member. A method for removing tissue in a body passage, the method comprising:
Advancing a catheter with a weight loss assembly attached to the distal end within the body;
Positioning the weight loss assembly adjacent to the tissue within the body;
Applying a distal force to the proximal end of the catheter to deflect a bending frame coupled to a distal portion of the catheter;
Rotating the bending frame while deflecting the bending frame to sweep the weight loss assembly in an arcuate path relative to the axis of the proximal end of the bending frame;
Rotating the torque shaft extending through the catheter and coupled to at least the cutter to remove the tissue and rotating the bending frame relative to the axis of the proximal end of the bending frame Rotating the sweep shaft independent of the torque shaft to sweep the weight loss assembly in an arcuate path.   57. The method of claim 56, further comprising advancing the cutter assembly axially within the body passage.   57. The method of claim 56, further comprising securing the sweep shaft to the catheter to prevent the bending frame from further bending or returning from bending.   57. The method of claim 56, wherein rotating the sweep shaft includes rotating the sweep shaft independent of the catheter.   57. The method of claim 56, wherein rotating the sweep shaft includes rotating the sweep shaft with the catheter.   57. The method of claim 56, further comprising connecting a proximal end of a catheter to a handle member, and rotating the sweep shaft includes rotating the sweep catheter independent of the handle member.   57. The method of claim 56, wherein a distal portion of the weight loss assembly includes at least one fluid port coupled to a fluid source and further includes delivering fluid through the fluid port.   57. The method of claim 56, wherein delivering a fluid comprises delivering a drug through the fluid port.   57. The method of claim 56, further comprising providing a spiral conveyor member within the weight loss device and transporting debris material out of the body via the spiral conveyor member.   65. The method of claim 64, wherein the helical conveyor member transports material out of the body without applying supplemental pumping or vacuum outside the catheter body. A method for navigating a guidewire and weight loss device through tortuous anatomy comprising:
Advancing the guidewire through the weight loss device to a region within the serpentine anatomy until advancement of the guidewire alone is prevented;
Advancing the weight loss device along the guidewire proximate the region;
Withdrawing the guidewire in the weight loss device;
Articulating the distal portion of the weight loss device to direct the distal end of the guidewire in a desired direction;
Advancing the guidewire across the region through the articulated weight loss device.   68. The method of claim 66, wherein withdrawing the guidewire within the weight loss device comprises fully withdrawing the guidewire within the weight loss device.   68. Withdrawing the guidewire within the weight loss device comprises partially withdrawing the guidewire within the weight loss device such that a distal end of the guidewire protrudes from the weight loss device. The method described in 1. A method for navigating a guidewire and weight loss device through tortuous anatomy comprising:
Advancing the guidewire through the weight loss device to a region within the serpentine anatomy until advancement of the guidewire alone is prevented;
Advancing the weight loss device along the guidewire proximate the region;
Withdrawing the guidewire in the weight loss device;
Articulating the distal portion of the weight loss device to direct the distal end of the guidewire in a desired direction;
Advancing the guidewire across the region through the articulated weight loss device.

Images