Orbital atherectomy automated traverse system

Abstract

Atherectomy devices and methods of using such atherectomy devices with automatic control from a control circuit and a number of sensors for advancing an abrasion element, as mounted to a rotational driven shaft and driven from a motor of a handle. If sensors attain threshold values, either above a preset threshold or below a preset threshold, the abrasion element may be retracted by a given distance and then readvanced within the lesion. This can be repeated bases on the sensor readings until the entire lesion is treated. Such threshold values can represent a problem with continued advancement of the abrasion element, such as an imminent stall or other related issues.

Description

ORBITAL ATHERECTOMY AUTOMATED TRAVERSE SYSTEMCross-Reference to Related Applications

[0001] This application claims priority to and the benefit of U. S. Provisional Patent Application No. 63 / 687,049, filed August 26, 2024, the entire contents of which are incorporated herein by reference in their entireties.Technical Field

[0002] The present invention is directed to atherectomy devices and systems includes aspects of automatic control for treating a lesion within a blood vessel.Background

[0003] Atherectomy devices and systems have been developed for treatment of a blood vessel and for reducing an occlusion or lesion with the blood vessel. Further treatments can be conducted after the atherectomy treatment. Balloon angioplasty provides a blood vessel treatment wherein a lesion can be compressed against the wall of a blood vessel. Atherectomy devices instead abrade the lesion with an abrasive element or crown to remove lesion tissue. During an atherectomy procedure, the abrasive crown is rotated and traversed across the lesion any number of times as a back-and-forth procedure to reduce the size of the lesion as occluding a lumen of the blood vessel. Such back and forth traverse movement is typically controlled by a knob provided on a handle of the atherectomy device that slides relative to the handle along a slot of the handle, and as the knob is operatively connected to move with a drive shaft and a rotational drive motor within the handle.Summary

[0004] The present invention is directed to atherectomy devices and methods of using such atherectomy devices with automatic control from a control circuit and a number of sensors for advancing an abrasion element, as mounted to a rotational driven shaft and driven from a motor of a handle. If sensors attain threshold values, either above a preset threshold or belowa preset threshold, the abrasion element may be retracted by a given distance and then readvanced within the lesion. This can be repeated bases on the sensor readings until the entire lesion is treated. Such threshold values can represent a problem with continued advancement of the abrasion element, such as an imminent stall or other related issues.

[0005] Specifically in one aspect of the present invention, an atherectomy device for treatment of a lesion within a blood vessel may include a handle including an interior for housing and supporting a rotational motor that is rotationally connected with a drive shaft that extends from a front portion of the handle, the handle further operatively supporting a linear drive device with a traverse motor that can operatively cause traversal of the rotational motor and the drive shaft in a longitudinal direction of the handle; an abrasion element at or near a distal end of the drive shaft for rotation with the drive shaft and for traverse movement along with the rotational motor and the drive shaft relative to the handle; at least one motor speed sensor for determining a speed of rotation or movement of at least one of the rotational motor and the traverse motor; at least one traverse sensor for determining one of a push force as applied from the traverse motor and a torque applied by the rotational motor to the drive shaft; and a control circuit for receiving data from the at least one sensor and for controlling at least one of the rotational speed of the rotational motor and the traverse speed of the traverse motor.

[0006] Preferably, the control circuit of the atherectomy device can include a microprocessor and memory with control instructions including a threshold value for the at least one traverse sensor. The control instructions can provide for a retraction of the traverse motor for a determined distance if the traverse sensor threshold value is reached after which the traverse motor can be readvanced.

[0007] Also, the control instructions of the control circuit can further provide for a comparison of the speed of rotation of the rotational motor to a rotational motor threshold value and for a comparison of the speed of rotation of the traverse motor to a traverse motor threshold value and for determining a direction of movement of the traverse motor. When one of the traverse motor torque sensor, the sensor for determining the push force of applied by the traverse motor, and the rotational motor speed of the rotational motor attains a respective threshold value, a retraction of the traverse motor and the abrasion element can be controlled to occur.

[0008] The traverse motor can be controlled to pause after retraction thereof. After pausing the traverse motor, the traverse motor can be controlled to readvance thereby readvancing the abrasion element within and along a lesion until a desired treatment is completed without causing a retraction of the traverse motor based upon an attainment of the respective threshold value for one of the traverse motor torque sensor, the sensor for determining the push force of applied by the traverse motor, and the rotational motor speed of the rotational motor.

[0009] The control circuit preferably further tracks a rate of change of any of the traverse motor torque sensor, the sensor for determining the push force of applied by the traverse motor, and the rotational motor speed of the rotational motor. The rate of change of any one of the traverse motor torque sensor, the sensor for determining the push force of applied by the traverse motor, and the rotational motor speed of the rotational motor can be compared to a respective rate of change threshold value for indicating a procedure stop event. After the procedure stop event is determined, the control circuit can stop the rotation of the rotational motor and retract the abrasion element from the lesion by movement of the traverse motor.

[0010] In another aspect of the present invention, a method of using an atherectomy device for treatment of a lesion within a blood vessel includes the steps of inserting an abrasion element, as connected with a drive shaft that is operatively driven by a rotational motor provided and supported within a handle, within the blood vessel to a location at or near the lesion; rotationally driving the abrasion element within the blood vessel by the rotational motor by way of the drive shaft; driving a linear drive device as operatively supported within the handle and having a traverse motor for operatively traversing the rotational motor and the drive shaft in a longitudinal direction of the handle and thus trans versing the abrasion element across at least a portion of the lesion; sensing a motor speed and / or movement of at least one of the rotational motor by a rotational motor sensor and the traverse motor by a traverse motor sensor and sending speed and / or movement data to a control circuit; sensing at least one of a push force as applied from the traverse motor by a transverse motor push force sensor and a torque applied by the rotational motor to the drive shaft by a torque sensor and sending push force and / or torque data to the control circuit; and receiving data at a control circuit for controlling at least one of the rotational speed of the rotational motor and the traverse speed of the traverse motor.

[0011] Preferably, the control circuit includes a microprocessor and memory with control instructions including a threshold value for the traverse motor sensor. The method can further include a step of retracting the traverse motor for a determined distance when the traverse sensor threshold value is reached followed by readvancing the traverse motor within the lesion.

[0012] Also, the method can include a step of comparing the speed of rotation of the rotational motor to a rotational motor threshold value and comparing the speed of rotation of the traverse motor to a traverse motor threshold value along with determining a direction of movement of the traverse motor. Moreover, monitoring the traverse motor torque sensor, the sensor for determining the push force applied by the traverse motor, and the rotational motor speed of the rotational motor with respective threshold values, and retracting the traverse motor and the abrasion element by way of the control circuit based upon the attainment of at least one of the respective threshold values.

[0013] Preferably, a step of pausing rotation of the traverse motor can be done after retraction thereof. Readvancing the traverse motor can be done after pausing the traverse motor, thereby readvancing the abrasion element within and along the lesion until a desired treatment is completed without causing any further retraction of the traverse motor based upon an attainment of the respective threshold value for one of the traverse motor torque sensor, the sensor for determining the push force of applied by the traverse motor, and the rotational motor speed of the rotational motor.

[0014] The method can further include tracking a rate of change of sensed values of any of the traverse motor torque sensor, the sensor for determining the push force of applied by the traverse motor, and the rotational motor speed of the rotational motor by the control circuit. Comparing the rate of change of any one of the traverse motor torque sensor, the sensor for determining the push force of applied by the traverse motor, and the rotational motor speed of the rotational motor to a respective rate of change threshold value can indicate a procedure stop event. After the procedure stop event is indicated, stopping the rotation of the rotational motor and retracting the abrasion element from the lesion by moving the traverse motor can be controlled by the control circuit.Brief Description of the Drawings

[0015] The present invention will be further explained with reference to the appended Figures, wherein like structure is referred to by like numerals throughout the several views, and wherein:

[0016] Fig. 1 is an atherectomy system in accordance with the present invention including a handle, drive shaft and abrasion device;

[0017] Fig. 2 is a schematic of an atherectomy system of the present invention illustrating a reusable control unit in operative connection with a single-use atherectomy device;

[0018] Fig. 3 is an illustration of the control unit and atherectomy device of Fig. 2 as usable together for performing an atherectomy method of the present invention;

[0019] Fig. 4 is a side view of a handle assembly as part of an atherectomy system of the present invention;

[0020] Fig. 5 is a top view of a handle assembly, a catheter, a drive shaft, and an electrical connection element of an atherectomy system of the present invention;

[0021] Fig. 6 is a top-view drawing of a distal end of the drive shaft, extending beyond a distal end of the catheter;

[0022] Fig. 7 is a perspective view of a handle assembly of the present invention with one side of a housing removed showing aspects of a rotational and translatable system of the present invention;

[0023] Fig. 8 is an enlarged view of a rotational motor of the present invention with aspects allowing its translation within the handle;

[0024] Fig. 9 is a longitudinal cross-section of the handle assembly of Figs. 7 and 8;

[0025] Fig. 10 is a schematic diagram of an example automated traverse system of the present invention;

[0026] Fig. 11 is a schematic diagram of a system summary of the automated traverse system of the present invention;

[0027] Fig. 12 is a schematic diagram of a system initialization aspect of the automated traverse system of the present invention;

[0028] Fig. 13 is a schematic diagram of an idle user interface aspect of the automated traverse system of the present invention;

[0029] Fig. 14 is a schematic diagram of an auto-traverse test sequence aspect of the automated traverse system of the present invention;

[0030] Fig. 15 is a schematic diagram of a treatment completion aspect of the automated traverse system of the present invention;

[0031] Fig. 16 is a schematic diagram of a traverse motor homing sequence aspect of the automated traverse system of the present invention;

[0032] Fig. 17 is a schematic diagram of a motor jog aspect of the automated traverse system of the present invention;

[0033] Fig. 18 is a schematic diagram of a threshold check aspect of the automated traverse system of the present invention;

[0034] Fig. 19 is a schematic diagram of a rate of change check aspect of the automated traverse system of the present invention; and

[0035] Fig. 20 is a schematic diagram of a manual override aspect of the automated traverse system of the present invention.Detailed Description

[0036] FIG. 1 is a schematic drawing of a typical known rotational atherectomy device. The device includes a handle portion 10, an elongated, flexible drive shaft 20 having an eccentric enlarged abrading head 28, and an elongated catheter 13 extending distally from the handle portion 10. The drive shaft 20 is constructed from helically coiled wire as is known in the art and the abrading head 28 is fixedly attached thereto. The catheter 13 has a lumen in which most of the length of the drive shaft 20 is disposed, except for the enlarged abrading head 28 and a short section distal to the enlarged abrading head 28. The drive shaft20 also contains an inner lumen, permitting the drive shaft 20 to be advanced and rotated over a guide wire 15. A fluid supply line 17 may be provided for introducing a cooling and lubricating solution (typically saline or another biocompatible fluid) into the catheter 13.

[0037] The handle 10 desirably contains a rotational drive, such as a turbine driven by fluid pressure or an electric motor, for rotating the drive shaft 20 at high speeds. The handle 10 typically may be connected to a power source, such as compressed air delivered through a tube 16 or by an electrical cord from an AC or DC power source. A pair of fiber optic cables 25, alternatively a single fiber optic cable may be used, are illustrated and may also be provided for monitoring the speed of rotation of the rotational drive and drive shaft 20 (details regarding such handles and associated instrumentation are well known in the industry, and are described, e.g., in U. S. Pat. No. 5,314,407, issued to Auth, and incorporated by references herein in its entirety). The handle 10 also desirably includes a control knob 11 for advancing and retracting the rotational drive and drive shaft 20 with respect to the catheter 13 and the body of the handle 10.

[0038] The abrasive element 28 in FIG. 1 can be an eccentric solid crown, that is attached to the drive shaft 20 near the distal end of the drive shaft 20. The term “eccentric” is used herein to denote that the center of mass of the abrasive element 28 is laterally displaced away from the rotational axis of the drive shaft 20. As the drive shaft rotates rapidly, the displaced center of mass of the abrasive element 28 causes the drive shaft to flex radially outward in the vicinity of the abrasive element 28 as it spins, so that the abrasive element 28 may abrade over a larger diameter (a working diameter) than its own rest diameter. Eccentric solid crowns are disclosed in detail in, for example, U. S. patent application Ser. No.11 / 761,128, filed on Jun. 11, 2007 to Thatcher et al. under the title, “Eccentric abrading head for high-speed rotational atherectomy devices”, published on Dec. 11, 2008 as U. S. Patent Application Publication No. US2008 / 0306498, and incorporated by reference herein in its entirety.

[0039] The present application preferably includes an electric motor in the handle, but may instead comprise an air- or nitrogen-fed turbine, as also well known. In this respect, many or all of the other elements of the atherectomy device of FIG. 1 may be used with the present disclosed head atherectomy device 10, including the catheter 13, the guide wire 15,the control knob 11 on the handle 10, the helically coiled drive shaft 20 and the eccentric solid abrasive element 28.

[0040] There are many combinations of features that may be included with the electrical device of the present invention. For instance, a device having relatively few features may be less expensive to produce than a relatively feature-laden device, and may be sold and marketed as such. Likewise, a device having a lot of features may be sold and marketed as a high-performance device, which may command a higher price than the relatively feature-free device.

[0041] FIG. 2 is a block diagram of an atherectomy device having an electric motor and relatively few features.

[0042] A control unit 140 is a non-disposable portion of an atherectomy system, which may be reused from procedure to procedure. The control unit may be mounted on a stand, as noted in FIG. 2, or may function as a stand-alone device that may be placed on a countertop or the like.

[0043] The control unit 140 preferably has an electrical connection 150 with the handle 110. In many cases, the control unit 140 functions as a power supply for the motor in the handle 110, and the electrical connection 150 is no more than the two conductive elements required for current flow (or, optionally, three, if a separate ground is used).Typically, the control unit 140 supplies a controllable and variable DC voltage to the handle 110, with the voltage varying in an open-loop fashion to control the rotational speed of the motor in the handle 110. Note that an AC voltage may also be used. For this schematically illustrated embodiment of the electrical connection 150, no communication is provided between the handle 110 and the control unit 140; the control unit 140 simply powers the motor in the handle 110. Note that in other cases, the electrical connection 150 may be more sophisticated and may include one- or two-way data communication between the control unit 140 and the handle 110; such a case is described below.

[0044] The control unit 140 can also include a reusable saline pump. Such a pump directs saline at a predetermined rate from a bag, or other suitable source, through a saline connection 190, into the handle 110. Suitable plumbing inside the handle 110 directs the saline into the catheter, where it fills the space surrounding the drive shaft and serves tolubricate and clean the system. The control unit 140 should preferably regulate the rate at which saline is pumped into the handle, and preferable also informs the operator of the status of the pump. These two functions are described below.

[0045] The saline pump preferably uses two pump rates, which are commonly designated as “low” and “high”. Typically, the low and high speeds are hard-coded in the firmware of the control unit 140. Alternatively, more than two discrete pump rates may be used, and / or a continuously varying pump rate may be used. Typically, the low pump rate is used to flush the system, at the beginning of the procedure before the drive shaft begins its rapid rotation. The high pump rate is typically used during the procedure, when the drive shaft is rotating rapidly. In some cases, the pump rate is varied between high and low automatically, depending on the control unit power supply setting and / or the desired rotational speed of the motor in the handle. In some cases, at the beginning of each procedure, the user is instructed to turn the pump on at a low flow rate, to wait for a particular time, and to then turn the flow rate up to high.

[0046] The device may use a weight sensor to monitor the level of the saline. Such a weight sensor may be a spring-like device from which a saline bag is hung. If the hung weight of the bag and its contents drops below a predetermined threshold, a switch in the weight sensor can be triggered. The saline typically arrives in a standard-sized bag, such as 200 milliliters, although any bag size may also be used. A weight sensor may also be used on a platform-like device, on which the saline bag may be placed. If the weight of the bag drops below a predetermined level, then the pump is turned off, the motor is powered down (to prevent damage to the device and to the patient that might occur from running the device without saline), and the operator can be notified.

[0047] The operator can be notified of the pump system status through the control unit 140. One simple notification system is described in detail below, although any suitable notification system may be used.

[0048] In one embodiment of a notification system, the status can be provided by three differently-colored light emitting diodes (LEDs), such as can be provided on the control unit 140. A “green” light may indicate that the pump is operating normally and that the handle 10 is powered properly. There can be an internal circuit that monitors a power supply(preferably a 48 volt power supply) for the handle 10. A “yellow” light may indicate that something is not right with the system; a door may be open, or there may be some other correctable problem with the system. A “red” light may indicate that the bag has run out of saline. It will be understood that other indication systems may be used as well.

[0049] The control unit 140 typically includes a cumulative time monitor, which ensures that the total operational time of the device does not exceed a predetermined threshold, such as nine minutes. Other predetermined time thresholds may be used, as well. The control unit 140 typically emits a warning and / or disables the motor once the cumulative operation time has been reached.

[0050] In some alternative designs, the electric motor is included within the control unit 140, rather than within the handle 110, and the electric connection 150 is replaced by a mechanical connection to transfer the rotation of the motor to the drive shaft.

[0051] FIG. 3 is an illustration of an exemplary control unit 40 and handle 10. In this example, the electrical connection 50 comes out the front of the control unit 40 and enters the handle 10, such as at a rear portion thereof. The catheter and drive shaft preferably attach to a front portion of the handle 10.

[0052] Many of the various device features, as discussed above, and for convenience are done so with respect to corresponding controls on the control unit 40. It will be understood that any suitable controls, with any suitable layout on the control unit 40, may be used for the described functions, and that the controls shown in the figures are merely examples.

[0053] Such a control unit is described in detail within US published patent application no. 20130253552, published September 26, 2013 to Schoenle et al, the entire contents of which are hereby incorporated by reference. Many of the various device features are described below, and for convenience are done so with respect to their corresponding controls on the control unit 40. It will be understood that any suitable controls, with any suitable layout on the control unit 40, may be used for the described functions and others, and that the controls shown in the figures are merely examples.

[0054] A running speed can be indicated on the control unit 40 as the actual rotational velocity of the proximal end of the drive shaft, in units of 1,000 RPM (revolutions per minute), or kRPM. The running speed 42 is typically updated several times per second, and in some cases may be displayed in relatively large LEDs that are readily visible to the practitioner. Rotational speeds of up to 200 kRPM are typical.

[0055] The rotational speed may be obtained from the electric motor itself. For instance, the motor may include one or more Hall effect sensors that produce an electrical signal each time the motor rotates past a particular point. The rotational speed is proportional to the rate of the signals, or, equivalently, is inversely proportional to the time intervals between the electrical signals. Alternatively, any suitable sensors and signals may be used.

[0056] The control unit 40 can also display a selected rotational speed. During operation, a control circuit (feedback loop) in the control unit 40 and / or the handle 10 can adjust the motor current and / or voltage to keep the actual running speed 42 as close as possible to the selected speed 43.

[0057] An event time can be display as the elapsed time for a particular run of the atherectomy device. It is typical for the atherectomy device to be rated only for a particular time, such as nine minutes, beyond which use is not recommended. A device may be repeatedly turned off and on during the course of a full procedure. Such switching off and on is permissible as long as the total cumulative time during which the device is actually on does not exceed a particular value, such as nine minutes. Typically, the handle 10 includes electronics that store the cumulative on-time, although such data may alternatively be stored in the control unit 40.

[0058] If the total operational time hits the threshold value, the control unit may either shut down, or may emit a warning advising the practitioner that the on-time limit has been reached. In some cases, the limit can be overridden by the practitioner. In other cases, reaching the limit disables the motor so that the device can no longer be used.

[0059] Plural, such as three, control buttons for “speed selection” can be provided and labeled “low”, “medium” and “high”, with an indicator light on each that corresponds to the selected speed. In general, for a particular model of handle 10 that is plugged into the control unit 40, there are preset speeds that are determined by the manufacturer. These speeds areautomatically recognized by the control unit 40, so that the practitioner need not enter them manually. Such recognition may take place by, for instance, storage of the preset speeds on the handle 10, storage of the preset speeds in a lookup table on the control unit 40, and / or lookups-as-needed of the preset speeds through a central database, such as over the Internet.

[0060] If the practitioner desires more fine control of the speed than is offered by the default low / medium / high presets, increment buttons may adjust the selected speed upward or downward by a predetermined increment, such as 10 kRPM, although any suitable increment may also be used.

[0061] A “brake override” button is typically used only when something gets stuck. During normal use, the guide wire remains extended from the handle, through the center of the drive shaft, past the abrasive element, and beyond the blockage. The drive shaft then rotates over the guide wire. During use, the guide wire remains rotationally stationary, and has a “brake” in the handle 10 that locks it rotationally and prohibits its rotation.Occasionally, there may be cases when something gets stuck, whether in the catheter itself, at the distal end of the drive shaft, or beyond the distal end of the drive shaft. When something gets stuck, the user may depress the “brake override” button 56, which allows the guide wire to rotate at a very low rotational speed. In some cases, the guide wire rotates at the same low rotational speed as the drive shaft. In other cases, the guide wire rotation is independent of the rotational speed of the drive shaft. Typically, the guide wire rotates as long as the brake override button is held down.

[0062] FIG. 4 is an illustration of a handle 10 in accordance with the present invention. The electrical connection 50 from the control unit 40 enters the handle 10 at a rear portion thereof. The catheter and drive shaft leave the handle 10 at a front portion thereof. As with the controller, the layout of the controls is merely exemplary, and other suitable layouts may be used.

[0063] The handle 10 is illustrated in FIG. 4 with a control knob 11, as discussed above, for longitudinally translating the drive shaft 20 with respect to both the guide wire 15 and the catheter 13, which remain stationary. In accordance with the present invention, the control knob 11 is optional in that the translational movement that can be imparted to the drive shaft 20 and thus the abrading head 28 can instead be provided by a linear drive device,discussed below. Translational movement of the abrading head 28 is preferably permitted over a desired range by the movement of the linear drive device. Preferably, the abrading head 28 is movable along a travel range of about 15 cm. Back and forth movements of the abrading head 28 can be used extensively during an atherectomy procedure, during which the rapidly spinning abrading head 28 can fully remove the blockage in the blood vessel.

[0064] FIGs. 4 and 5 illustrate the handle 10 with the control know 11, with the understanding that such a control knob 11 can be provided as a manual approach to translational movement of the drive shaft 20 even if an automated system, as discussed below, is also provided. Such a control knob 11 may also be provided as an on / off switch for the operator to turn on and off the electric motor in the handle 10.

[0065] The handle 10 may include a duplicate set of speed selection buttons 12, which can repeat the functionality of the corresponding buttons on the control unit 40.Having speed selection buttons 12 on the handle 10 itself can be a convenience for the practitioner.

[0066] Lever 14 can be provided as a brake for the guide wire 15, which, when engaged, prevents rotation of the guide wire 15 as the drive shaft 20 is rotated. In some cases, the guide wire brake lever 14 can be locked when the lever 14 is horizontal, as in FIG. 4, and is unlocked when pulled upward by the practitioner.

[0067] FIG. 5 is a top-view drawing of the handle 10 of FIG. 4. In addition to showing the control knob 11, the speed selection buttons 12 and the guide wire brake 14, FIG. 5 shows the electrical connection 50, which is typically a 14-foot-long cable, although other suitable lengths may be used, and shows the catheter 13, typically connected to the body of the handle 10 with a strain relief at the tip of the handle 10. The distal end of the drive shaft 20 is visible in FIG. 5, and is shown in more detail in FIG. 6.

[0068] FIG. 6 is a top-view drawing of the distal end of the drive shaft 20, extending beyond the distal end of the catheter 13. The drive shaft 20 is typically a helically-wound coil of wire, although any suitable mechanism for delivering torque from the electric motor to the abrasive element 28 may be used as a drive shaft. For instance, an alternative drive shaft may be a solid or slotted tube of plastic or metal.

[0069] The abrasive element 28 shown in FIG. 6 is an enlarged portion of the drive shaft 20, with an abrasive material coated on the exterior of the enlarged portion.Alternatively, any suitable abrasive element may be used, including an element (a so-called “crown”) having a center of mass that is laterally displaced from the rotation of the drive shaft 20 (an “eccentric” solid crown) and having an abrasive exterior. The eccentric solid crown is typically attached to the drive shaft 20, although it may alternatively be made integral with the drive shaft 20. The eccentric solid crown is preferably attached near, but not at, the distal end of the drive shaft 20, although it may alternatively be attached at the distal end of the drive shaft 20.

[0070] FIG. 7 is a top-view drawing of the handle 10, which is opened for showing internal aspects of the handle 10. FIG. 8 is a close-up view of a carriage 60 inside the handle 10 of FIG. 7. In practice, the handle remains closed before, during and after the procedure. As above, the catheter 13 and drive shaft 20 exit the front portion of the handle 10 in the view of FIG. 7.

[0071] As shown in FIGs. 8 and 9, the electric motor 70 itself can reside within and be operatively supported to move along with the carriage 60. The exterior of the carriage 60 can also function as a heat sink for the motor. The motor 70 is powered by a series of electrical wires 61, which connect to the electrical connection 50 that in turn connects to the control unit 40, as described above.

[0072] The carriage 60 and motor 70 can travel longitudinally with a predetermined range of travel, and do so with the carriage 60 being mounted on wheels 62 that engage respective rails 71 and 72 within the handle 10. Alternatively, other translating mechanism may be used. The handle 10 is typically used for a single procedure and then disposed, so the wheels and tracks should be sturdy, but generally need not be designed for an especially long lifetime.

[0073] The carriage 60 has an optional on / off toggle switch 63 on its top (schematically illustrated in FIG. 8), which corresponds to the off / off button on the control knob 11. During use, the control knob 11 can lie directly above the toggle switch 63, and the practitioner may depress the knob 11 to turn the motor on and off.

[0074] There may be one or more gears 64 that step up or step down the rotation between the motor 70 and the drive shaft 20. For instance, the motor itself may have a maximum rotational speed, such as for example 50 kRPM, and a series of differently-sized gears may step the rotation up 4. times, for example, to 200 kRPM for the drive shaft. Other motor and drive shaft rotational speeds are contemplated, including the use of any number of meshed gears at desired ratios as well known.

[0075] An advantage to having a geared system is that the guide wire may be routed through the center of a gear that is positioned to the side of the motors axis of rotation, rather than through the center of the motor. This simplifies the mechanical system.

[0076] Control element 65 can also be provided at a rear portion of the handle 10 as another on / off switch, much like the toggle switch 63. One difference, however, is that the switch 65 can be linked to the guide wire brake lever 14. In the illustrated embodiment, when the brake is released, the brake lever 14 is in an up position, and can engage with the switch 65 to shut off the motor 70, regardless of the state of any other on / off switches. When the brake is engaged, the switch 65 preferably allows any other switch to toggle the motor on and off. Accompanying circuitry for the switch 65 is also preferably provided within the rear portion of the handle 10 and as connected with a power circuit for the motor 70 including any number of on / off switches.

[0077] Elements 66, 67 and 68 involve mechanical aspects of keeping the rapidly spinning drive shaft contained and stable, and of ensuring functional seals to keep fluids contained adequately. Elements 66 and 67 are telescoping elements, such as concentric hypo tubes, which are tight enough to provide adequate fluid seals, but loose enough so that they do not significantly rob the system of torque due to excessive friction.

[0078] As noted above, the interior of the handle 10 may not be a dry system. Vapor and an amount of leaked liquid (saline), such as provided by fluid supply line can serve to cool the motor 70 and any other moving parts in the handle 10 and in the catheter 13. One or more portions of the substantially hollow interior of the handle 10 may be open, so that fluid can collect in them. One or more other portions of the interior of the handle 10 may be sealed from the fluid to protect electronics, such as a control board, a power circuit, memory, and / ora microprocessor, as illustrated schematically in FIG. 9 at a lower rear portion 73 of the handle 10.

[0079] The motor and gears, spinning the drive shaft up to 200 kRPM, may produce significant vibrations inside the handle. In general, these vibrations are undesirable, and it is generally preferable to dampen these vibrations whenever possible. The telescoping portions 66 and 67, extending from the proximal edge of the handle 10 to the carriage 60, and from the carriage 60 to the distal edge of the handle 10, have their own resonant frequencies. The resonant frequencies of the portions can vary, depending on where in the range of travel the carriage 60 actually is. As a result, completely avoiding a resonant frequency during use is generally difficult. One way to dampen the vibrations for a large range of resonant frequencies is to use one or more strain reliefs 68 within the coupling between the carriage 60 and telescoping portions 66 and 67.

[0080] The control unit 40 (also referred to as a controller) is preferably provided as a non-disposable portion of the system, and can include most of the electronic functions of the device that aren't directly related to driving the motor 70. For instance, the control unit 40 can recognize which type of handle is plugged into it, can include controls for setting the desired speed of the motor, and can include controls for the pump that delivers saline down the catheter 13. The control unit 40 can also include a microprocessor, memory, and programming or instructions for operation of the system of the present invention according to any number of different operating modes.

[0081] The control unit 40 preferably also supplies power to the power circuit of the handle 10 and may provide for one or two-way exchange of data by way of the electrical connection 50 to the handle 10. In addition to having the control knob 11, if provided, and the associated mechanical structure that can advance and retract the abrasive element with respect to the catheter, the handle 10 preferably includes the electric motor 70 and the mechanical coupling of the motor 70 to the drive shaft 20 by way of gearing 64.

[0082] As an alternative, the electric motor 70 may be located within the control unit 40, rather than in the single-use handle 10. Locating the motor in the control unit 40 would require an additional mechanical coupling between the control unit 40 and the handle 10 in addition or as part of the electrical connection 50.

[0083] As shown schematically in FIG. 9, a linear drive device 75 can be provided in accordance with an aspect of the present invention for translating the carriage 60 and thus the motor 70 and drive shaft 20 distally and proximally along with the abrasive element 28 provided at the distal end of the drive shaft 20. The linear drive device preferably has a range of movement in the linear direction of the rails 71 and 72 that permits sufficient movement of the abrasive element 28 along or within a lesion of a blood vessel and can correspond to a slot length that accommodates movement of the knob 11, if such is provided.

[0084] The linear drive device 75 can comprise any known or developed linear drive, such as including a worm or lead screw type drive, a rack and pinion type drive, hydraulic or pneumatic piston(s), a linear motor, or the like. Such a linear drive device 75 may also comprise an electric motor, pneumatic or hydraulic turbine for rotating a lead screw or gear or the like to create the linear movement. Such a linear drive device 75 can include any number of guide elements, such as sliding surfaces, rails, rods, and the like that set the linear direction of movement. An operative connection of the linear drive device 75 to the carriage 60 is illustrated in FIG. 9 at 76. This operative connection is preferably an element that translates the linear movement of a drive portion of the linear drive device to the carriage 60 along the desired range of linear movement. The linear drive device 75 can be operatively supported to the internal structure of the handle 10 by any number of support elements (not shown) and can preferably fix a portion of the linear drive device 75 relative to the handle 10 and so that a movable portion of the linear drive device 75 can translate the carriage 60 via the operative connection 76.

[0085] As also illustrated in FIG. 9, the control unit 40 can be operatively connected with both the rotational motor 70 and the linear drive device 75, such as illustrated at 50 and 52, respectively. As above, the connections 50 and 52 can include electrical power to connect the control unit 40 with respective power circuits of the motor 70 and the linear drive device 75. These connections 50 and 52 preferably also include data transmission lines for controlling aspects of the motor 70 and linear drive device 75, such as speed of rotation and translation along with directional and distance of movements, and the like, and as such data lines are operatively connected with a control circuit. Data transmission may also include data collected from the motor 70 and linear drive unit 75 as such data can be sensed by any number of sensors to provide feedback to the control unit 40 for performing a medical procedure, as further described below.

[0086] FIG. 9 illustrates the linear drive device 75 as schematically positioned between the motor 70 and the front portion of the handle 10 (i.e. where the drive shaft 20 exits the handle 10). However, it is contemplated that such a linear drive device 75 can be positioned anywhere within the interior of the handle 10 and be operatively supported and connected with the carriage 60 to impart linear movement in both directions. Preferably, the linear drive 75 is positioned offset from the drive shaft 20 similar to the motor 70 so as not to interfere with the rotation of the drive shaft 20. The linear drive device can be preferably positioned between the motor 70 and the rear portion of the handle 10 to be closer to the control board and electronic power and control circuitry as may be provided by a printed circuit board within the rear lower portion 73 of the handle 10.

[0087] The present invention includes automation features that allow for more consistent and reliable blood vessel preparation by removing the need for manual traversing of the lesion, such as by an operator moving the carriage 60 and thus the drive shaft 20 and abrasive element 28 back and forth across a lesion. To automate the system, the hardware components described above, including the carriage 60, the motor 70, and the linear drive device 75, can work together with embedded software to communicate a desired or predetermined movement (translation and rotation) of the abrasive element 28 for blood vessel preparation.

[0088] A system according to the present invention preferably includes a number of sensors provided to the various hardware components, including the rotational motor 70 and linear drive device 75 and can measure the force applied by the linear drive device 75 in the advancing direction of the abrasive element 28, motor current at one or both motors (drive shaft rotational motor 70 and any traverse motor of the linear drive device 7), and other mechanical indicators. A sensor is described above for monitoring rotation of the drive shaft 20, such as by using a hall effect sensor. Force sensors to determine a push force, for example, can include piezoelectric sensors, piezoresistive sensors, capacitive force sensors, inductive force sensors and the like. These sensors may be positioned in-line with the motor carriage 60 to detect changes in the force required for the carriage 60 to advance, or positioned in another manner to measure the linear force needed to advance the system further. These force sensors may also be placed on a separate carriage system not attached to the telescoping driveshaft hypotubes in order for a position differential to be measured between the motor 70 and the sensors. This differential may then register a varying forcereading by the sensor. Torque sensors can include rotary torque sensors to allow for the continuous measurement of torque differentials as the rotational motor 70 spins the driveshaft 20. Force and torque sensors may be positioned, as schematically indicated in FIG. 9 at 77, in-line with the rotational elements of the atherectomy device, potentially acting as a coupler system between the drive shaft 20 and the hypotubes connecting to the carriage 60. Electric current measurements read by the control unit and its control circuitry from either the linear drive device 75 or the motor 70 or both can also serve as a system control indicator, as changes in torque applied to the abrasion element 28 or drive shaft 20 will be indicated by a linear change in the required electrical current to the system. Sensors can be implemented through the use of fiber optics that may be run parallel with the drive shaft 20 and the abrasion element 28. Such sensors can be positioned at or near the distal end where lesion engagement is to take place, or may be positioned as load or torque cells proximally and operatively coupled with the drive shaft 20 or any other rotational element within the handle 10.

[0089] A software algorithm is preferably provided including instructions to use the outputs from the sensors as inputs to the control system in order to assess the state of the atherectomy device in use and to control the atherectomy device in accordance with a determined operation. One specific embodiment would include a sensor array for reading a linear push force, motor current from both the traverse motor and the rotational motor 70, torque values and other system indicators as deemed necessary for monitoring the systems state. The system would include a microcontroller provided with memory including the instructions for use and control of the atherectomy device. The microcontroller can be inboard within the atherectomy device handle 10 or may be provided within a data connected control unit 40, as described above. Data communication can be wired as described above or can utilize wireless technology as known or developed, such as blue tooth connectivity. The microprocessor can include control circuitry that compares the sensed input values from the sensor array against predetermined threshold values stored within memory, such as in the form of a data table, and based upon such comparison control the drive shaft rotational motor 70 or the traverse motor (directionally and rotationally) for controlling the speed of rotational abrasion by the abrasive element 28 and the speed and direction of traverse movement of the abrasive element 28 by the linear drive device 75. For example, the control circuitry can determine a desired speed for rotation of the drive shaft 20 and abrasive element 28 and / orthe rate of traverse movement of the abrasive element 28 by the linear drive device 75 along with the direction of traverse linear movement of the abrasive element 28 for advancement to and along a lesion or retraction from the lesion.

[0090] In accordance with the present invention, automation components can work together to prepare a calcified lesion for subsequent treatment. In an example operation, powering on the atherectomy device can cause the linear drive device 75, under control of the embedded software, to advance the abrasion element 28 into the lesion at a specified rate. As the abrasion element 28 encounters the lesion, sensors can record an indicator, such as a push force or torque, and relay that data to the control circuitry including the microprocessor and its embedded software. The software can determine the state of the atherectomy device and make further decisions on how to continue to proceed with a specific procedure or portion thereof. For example, if the control circuit determines that an indicator value as sensed by one of the sensors is below a threshold value as stored in the control circuit memory, the linear drive device 75 and thus the abrasion element 28 can continue advancing. However, if the control circuit determines that an indicator value sensed by one of the sensors has surpassed the predetermined threshold value stored in memory, the control circuit can halt the advancing of the abrasion element 29. The control circuit can further determine that the abrasion element 28 is to be retracted, in which case the linear drive device would be activated to retract the motor 70, the drive shaft 20, and the abrasion element 28, with or without rotation. The retraction can be controlled as a predetermined distance and at a predetermined rate of retraction in order to relieve stress on the system. It is further contemplated that a pause can be controlled to occur followed by a new advancement of the motor 70, drive shaft 20, and abrasion element 28 back toward and to a new engagement with the lesion. Such a cycle can be repeated until the procedure is complete or it is otherwise terminated. Preferably also, there is programmed a safety threshold for one or more of the sensed values, upon which attainment of such safety threshold could cause the atherectomy device to stall or stop select operation(s) to prevent injury to the patient and require the operator too restart the atherectomy device.

[0091] Completion of a procedure can be indicated by a significant drop in any of the sensed indicators. Based on the sensor inputs, the microprocessor could calculate changes in those inputs over time using pre-programmed calculations over predetermined intervals. Using a separate set of thresholds, the microprocessor could compare these rates of change insensor values against the thresholds to determine whether a procedure stop event has occurred. For example, if such an indicator value is detected by the control circuit, the atherectomy device could ramp down the rotational speed of the motor 70 in accordance with a predetermined rate until the abrasion element 28 stops spinning and then the control circuit can control the linear drive device 75 to retract the abrasion element 28 from the lesion followed by removal of the atherectomy device from the patient.

[0092] The rates of advancing and retracting the linear drive device 75 and thus the abrasion element 28 can be varied or modified depending on any number of variables, such as based on the type of lesion and characteristics thereof including the size of the lesion (radially and / or axial length), make up of the lesion, hardness of softness of the lesion tissue, and the like. The control circuit can also include programming to automatically adjust rotational speed during a procedure dynamically based on sensor values. As such, sensed indicator values during a procedure can be used to determine optimal speed for rotation of the abrasion element 28 for treatment of a particular lesion, which speed can be adjusted during the procedure. Such an automated atherectomy device and system can remove human error from blood vessel preparation in order to ensure a consistent procedural outcome.

[0093] FIG. 10 shows a flowchart of an example of an automated traverse system of the present invention, in accordance with that set out above. Box 100 indicates the activation of an atherectomy device according to the present invention followed by the start of rotation of the drive shaft 20 and abrasion element 28 as indicated at box 102. Box 104 indicates the advancing of the abrasion element 28 by the linear drive device 75, which is preferably at a predetermined constant rate, but need not be. As the rotation of the abrasion element 28 and the advancement thereof have begun, feedback sensors can be provided to provide sensed indicator values to the control circuit, as indicated at box 106. A decision step is indicated at 108. If a threshold value is reached as to any of the sensors of the sensor array, the abrasion element 28 can be retracted as indicated at box 1 10 based upon a “yes” value of the decision step followed by a traverse movement of the abrasion element paused based on a pause of the linear- drive device 75 as at box 112. Rotation of the abrasion element 28 can be stopped during the retraction and traverse pause, although need not be. Then the steps 104 and 106 can be repeated until the decision step again at 108. If the decision at step 108 is “no”, a next decision step 116 would determine if the procedure is complete, as such is based on the control circuit programming for a selected procedure. If not, the procedure will continue byrepeating the steps starting at step 104, same as above. If the procedure is determined to be complete, the rotation of the abrasion element 28 can be stopped as at box 116 followed by retraction of the atherectomy device from the patient as indicated by box 118.

[0094] FIGs. 11-18 are process flow charts of a more detailed example of the procedures of the present invention as can be performed by an automated system of the present invention. FIG. 11 is a schematic illustration of such a process as broken down into four systematic conceptual general steps. The general concepts include a procedural start step as shown at 200, followed by a system initialization function as shown at 202, an idle user interface function as shown at step 204, an auto-traverse function as shown at step 206, a treatment complete function as shown at step 208, and a procedural completion shown at step 210.

[0095] FIG. 12 illustrates in greater detail the system steps of the system initialization function 202. A system initialization step 300 begins with a step 302 of checking that the handle 10 of the atherectomy device is operatively connected with the saline pump. The next step 304 is a power check of the pump, handle, and control unit or console. Then, a check as shown at 306 may be performed, for connectivity of the control unit or console to the handle, such as by Bluetooth. A next step can comprise a traverse motor homing sequence step 308, which has to do with positioning the linear drive device 75 in a home position as described in more detail below, followed by a completion of the system initialization to an idle user interface as indicated at step 310.

[0096] FIG. 13 shows the start of the idle user interface at step 400. At step 402, a console of the control unit can display the idle-state user interface. At step 404, the pressing of a start test button can start a new test procedure. If the start button has been pressed, an auto-traverse test sequence can follow as indicated at step 406. If a motor jog button is pressed instead of the start test button, a motor jog procedure can be initiated, as indicated at 410. Likewise if a home traverse button is pressed instead of the start test or motor jog buttons, a home traverse motor button can be selected as indicated at 412 to start a traverse motor homing sequence as shown at 414. If either the motor jog button or home traverse motor button are selected and after the sequences followed by those selections has been conducted (as described below) the console display can return to the console display of the idle-state user interface step at 402. These steps will continue with the pressing of either themotor jog or home traverse buttons until the new test button is pressed to start an auto traverse test sequence, as below.

[0097] An auto-traverse test sequence can be conducted after such is selected at step 404, as above, and as illustrated in FIG. 14. An initiation of the auto-traverse test sequence is indicated at step 500 followed by a traverse motor homing sequence for setting the linear drive 75 in a home position, as discussed in more detail below and indicated by step 502. When step 502 is finished, the auto-traverse test sequence can continue with setting the rotational motor 70, as indicated at step 504, to a predetermined low rotational rate such as for glide assist, for example. At the same time, a traverse motor of the linear drive 75 can be set to a predetermined low speed as in step 506, while also activating a torque sensor and a linear force sensor as indicated at steps 508 and 510. Preferably, steps 504-510 can be initiated at the same time. Following the initiation of steps 504-510, the control circuit including the microprocessor and programmed instructions within memory can be providing sensed values of the motor speeds and indicated values of the linear force and torque sensors as shown at step 512. The next step 514 checks whether a manual override button has been pressed (sequence of which is described below). Also, after step 512, the user interface is preferably caused to display the readings from the sensors and motor speeds, as in step 516. If the manual override button has been selected, the process with proceed with initiation of the manual override as shown at step 518. If the manual override button has not been selected, a threshold value check can be conducted as at step 520 to the sensed indicators of the sensors and motors (further described in detail below with reference to FIG. 18).Following the threshold value check, a rate of change check can be conducted as indicated at step 522 that compares the calculated rate of change in sensor input values as calculated by the microprocessor and / or the control unit as described above to the pre-programmed set of threshold values for these rates of change. At step 524, a determination of whether the treatment procedure is complete is conducted based upon a treatment procedure that has been determined for a specific lesion. If treatment is not complete, the process returns back to step 512 for continued treatment according to that set up above. If completed, initiation of a treatment procedure follows, as described below.

[0098] The treatment completion process is illustrated in FIG. 15. Step 600 indicates the start of this process followed by a step 602 of setting the rotational motor speed back to the glide assist rate and starting the traverse motor homing sequence, as noted above anddescribed below. After the traverse motor homing sequence, the spin speed is preferably reduced to zero and the traverse motor of the linear drive device is preferably stopped, as indicated at steps 606 and 608, respectively. Then, the handle and saline pump can be powered down, as indicated at step 610 followed by a completion of this process at step 612.

[0099] In certain of the processes discussed above, a traverse motor homing sequence is noted as a part of such processes. FIG. 16 illustrates this sub-process or sequence to be conducted in such other processes. Step 700 is the start of this sequence for traverse motor homing. In step 702, the control circuit reads data from a traverse motor encoder (as a sensor) that indicates a motor count. A motor count is an output of an encoder that provides a measurement or count of the traverse motor’s position as it is rotated. If the motor count is zero, meaning the traverse motor is “home”, then the traverse motor is stopped as indicated at step 706 followed by a return to the previous sequence of the noted processes above and as indicated at step 708. If the motor count is not zero, a message can be displayed on the console as to the homing operation, as indicated in step 710, followed by a traversal of the abrasion element 28 and the linear drive device 75 to a home position, preferably at a preprogrammed “jog” speed. The jog speed is a higher motor speed as compared with a treatment speed to advance the abrasion element 28 for treatment of a lesion, which treatment speed compares with the slower glide assist speed, discussed above, used to initialize the atherectomy device. A motor jog can be done as described above in connection with the flow chart of FIG. 13, particularly at step 410.

[0100] FIG. 17 illustrates another sub-process as usable within other sequences or processes discussed above. Step 800 is an initiation of a motor jog process followed by step 802 wherein the control circuit checks the motor count of the traverse motor, and at step 804, the traverse motor advances or retracts the abrasion element 28 depending on the direction of motor jog selected. As indicated in decision step 806, a check is made on whether the motor limit has been reached, indicating the motor has reached the maximum travel distance of the handle and / or traverse knob 11. If the limit has been reached, the user interface can display a motor limit error message, step 808, and the traverse motor can then be stopped, step 810. After that a return to the previous sequence can be done as indicated by step 812. If the motor limit has not been reached, a check is made as to whether a motor jog button has been released at step 814. If yes, the process proceeds with stopping the traverse motor and returning to the previous sequence as in steps 810 and 812,respectively. If the motor jog button has not been released, the process can return to the step 802 of reading the traverse motor count. The motor job button can be pressed by an operator before the start of an atherectomy procedure, for example, (see again FIG. 13 at step 410) or when the operator desired to manually override the system.

[0101] Details of the threshold check, as noted above with reference to FIG.14, is illustrated in FIG. 18. Specifically, a threshold check is initiated at step 900 followed by a first decision step 902 based upon a comparison of a sensor value signal as provided to the control circuit from a force and / or torque sensor as compared to a predetermined threshold value for that sensed value. If the sensed value is greater than the threshold value, the process will proceed to step 904, after which the control circuit will cause a reduction of the rotational speed of the rotational motor 70, as noted at step 906, and will also cause the traverse advancement by the linear drive device to pause, as noted at step 908. Following these two motor control steps, the abrasion element 28 is retracted by a preset distance, as noted at step 910. After retraction of the abrasion element 28, the rotational motor 70 can be reset to the desired treatment rotational rate, as noted at step 912, and the traverse advancement by the linear drive device 75 can be reset to its desired treatment rate. The process could then revert to the previous process, such as step 522 of FIG. 14. Going back to decision step 902, if the sensor value is not above the threshold value, the process can proceed to a next decision step asking whether the sensed value is below a lower threshold value. If yes, the process may proceed to step 920 to cause the traverse rate to be set to the jog rate followed by setting the rotational motor rate of rotation to the glide-assist rate, as in step 922. By this process, if there is no significant force or torque load on the system, and the sensor values are below a lower-limit threshold, then the abrasion element 28 and drive shaft 20 can advance at a higher rate, which reduces the time to reach the lesion site and begin treatment. The higher traversal rate is the “jog” rate. The rotational rate can be set at a lower glide-assist rate to assist in advancing the abrasion element and drive shaft. After resetting the traverse and rotational rates, the process may proceed to step 916 to return to the previous process.

[0102] As shown in FIG. 14, a rate of change check can be conducted at step 522 subsequent to the above threshold check. Such a rate of change check process is shown in FIG. 19, with the initiation thereof at step 1000. At step 1002, the control circuit calculated a rate of change, preferably, of both a force sensor and a torque sensor. After suchcalculation(s), a decision step 1004 compares the rate of value increase to a programmed start threshold. If the rate of value increase is greater than the programmed start threshold, the process may proceed to step 1006, which queries whether or not the programmed start threshold has been previously reached. If no to this query, the rotational motor rate and the traverse motor advancement speed are set to their respective treatment rates, as noted at step 1008 followed by a providing a “NO” value to the previous process as indicated at step 1010. If, however, at step 1006 the answer is yes to the “threshold previously reached” query, a next decision step 1012 further queries if the rate of value decrease is greater than a programmed exit threshold. Also, at step 1004, if it is determined that the rate of value increase is greater than the programmed start threshold, the process will proceed to step 1012. An answer of no at step 1012 will result is the process proceeding to step 1010 with a “NO” value returned to the previous process. If the answer is yes at step 1012, the process will proceed to step 1014 with a “YES” value returned to the previous process. By this process, the abrasion element 28 and drive shaft 20 can traverse to the lesion site, at which encounter with the lesion, there will be a sharp increase in both force and torque. This event is detected by comparing that increase in the force and torque against the “start threshold”, and if the sensed value is above the threshold, then the system knows that the lesion has been engaged and that a treatment is ready to begin. As the rotating abrasion element is treating the lesion, the force / torque loads will increase, potentially leading to another sharp increase in those values, again exceeding the start threshold. The “threshold previously reached” query and decision can detect that the system has already begun the treatment and thus no need to reinitiate a treatment process and that step can be bypassed. Providing a “NO” value to the auto-traverse test sequence, as above, resets the automated loop to continue treating the lesion and checking for other events. Similarly, when the abrasion element 28 fully treats the lesion and exits the distal end of the lesion, the system will experience a sharp drop in both force and torque. This steep rate of change drop can be compared against an “exit threshold” that when exceeded, indicates to the system that the system has completed its treatment of the lesion and can begin the “treatment complete” process protocol. By providing a “YES” value to the auto-traverse test sequence, also as above, the “treatment complete” process can proceed.

[0103] FIG. 20 is an illustration of a manual override process, as such process may be initiated as well from one of the previously described processes, such as the manualoverride step 518 of the auto-traverse test sequence discussed above. The manual override option provides a safety feature to the system, as an operator in then able to cease the system’s automated features and take over manual control of the device’s positioning and motor rotational rates. Step 1100 indicates the start of a manual override process. At the start, the traverse motor of the linear drive device 75 is stopped and rotational motor 75 is set to the glide assist rate, as above, and as indicated at steps 1102 and 1104, respectively. Next, the control circuit can read / write manual signals, as indicated at step 1106. This means that the sensor array may continue to relay data to the microprocessor in the manual mode to display sensed information to the operator. At this point manual override can be conducted by an operator by the manual selection and adjustment of certain control aspects of the atherectomy system of the present invention. Steps 1108 through 1120 indicate such manual selections for adjustments and the control aspects. Step 1108 can be the adjustment of traversal speed, which causes traversal speed adjustment at step 1122. Step 1110 can be the adjustment of the rotational speed of the drive shaft 20, which causes rotational motor’s 70 speed to be adjusted. Step 1112 can cause an initiation of a manual jog, which causes a motor jog process to be conducted, step 1126. Step 1114 can cause a traverse motor homing sequence, as discussed above, and indicated at step 1128. Step 1116 can include pressing a button to cause a return to a previous sequence, step 1130, and a return to the automated process. Step 1118 can be a button press to end the procedure and a completion of a treatment, step 1132. Step 1120 can be a button press to do an emergency stop of the entire atherectomy device, in which case the traverse and rotational motors can be stopped immediately, step 1134. Step 1136 indicates a procedural completion of the manual override. With such a manual override, an operator can take control of the automated process based on a change in status of an aspect of a procedure that is being conducted or based on other experiences or the like.'ll

Claims

Claims1. An atherectomy device for treatment of a lesion within a blood vessel comprising:a handle including an interior for housing and supporting a rotational motor that is rotationally connected with a drive shaft that extends from a front portion of the handle, the handle further operatively supporting a linear drive device with a traverse motor that can operatively cause traversal of the rotational motor and the drive shaft in a longitudinal direction of the handle;an abrasion element at or near a distal end of the drive shaft for rotation with the drive shaft and for traverse movement along with the rotational motor and the drive shaft relative to the handle;at least one motor speed sensor for determining a speed of rotation or movement of at least one of the rotational motor and the traverse motor;at least one traverse sensor for determining one of a push force as applied from the traverse motor and a torque applied by the rotational motor to the drive shaft; anda control circuit for receiving data from the at least one sensor and for controlling at least one of the rotational speed of the rotational motor and the traverse speed of the traverse motor.

2. The atherectomy device of claim 1, wherein the control circuit includes a microprocessor and memory with control instructions including a threshold value for the at least one traverse sensor.

3. The atherectomy device of claim 2, wherein the control instructions provide for a retraction of the traverse motor for a determined distance if the traverse sensor threshold value is reached after which the traverse motor can be readvanced.

4. The atherectomy device of claim 3, wherein the control instructions of the control circuit further provide for a comparison of the speed of rotation of the rotational motor to a rotational motor threshold value and for a comparison of the speed of rotation of the traversemotor to a traverse motor threshold value and for determining a direction of movement of the traverse motor.

5. The atherectomy device of claim 4, wherein when one of the traverse motor torque sensor, the sensor for determining the push force of applied by the traverse motor, and the rotational motor speed of the rotational motor attains a respective threshold value, a retraction of the traverse motor and the abrasion element is controlled to occur.

6. The atherectomy device of claim 5, wherein the traverse motor is controlled to pause after retraction thereof.

7. The atherectomy device of claim 6, wherein after pausing the traverse motor, the traverse motor is controlled to readvance thereby readvancing the abrasion element within and along a lesion until a desired treatment is completed without causing a retraction of the traverse motor based upon an attainment of the respective threshold value for one of the traverse motor torque sensor, the sensor for determining the push force of applied by the traverse motor, and the rotational motor speed of the rotational motor.

8. The atherectomy device of claim 7, wherein the control circuit further tracks a rate of change of any of the traverse motor torque sensor, the sensor for determining the push force of applied by the traverse motor, and the rotational motor speed of the rotational motor.

9. The atherectomy device of claim 8, wherein the rate of change of any one of the traverse motor torque sensor, the sensor for determining the push force of applied by the traverse motor, and the rotational motor speed of the rotational motor can be compared to a respective rate of change threshold value for indicating a procedure stop event.

10. The atherectomy device of claim 9, wherein after the procedure stop event is determined, the control circuit stops the rotation of the rotational motor and retracts the abrasion element from the lesion by movement of the traverse motor.

11. A method of using an atherectomy device for treatment of a lesion within a blood vessel, the method comprising:inserting an abrasion element, as connected with a drive shaft that is operatively driven by a rotational motor provided and supported within a handle, within the blood vessel to a location at or near the lesion;rotationally driving the abrasion element within the blood vessel by the rotational motor by way of the drive shaft;driving a linear drive device as operatively supported within the handle and having a traverse motor for operatively traversing the rotational motor and the drive shaft in a longitudinal direction of the handle and thus transversing the abrasion element across at least a portion of the lesion,sensing a motor speed and / or movement of at least one of the rotational motor by a rotational motor sensor and the traverse motor by a traverse motor sensor and sending speed and / or movement data to a control circuit;sensing at least one of a push force as applied from the traverse motor by a transverse motor push force sensor and a torque applied by the rotational motor to the drive shaft by a torque sensor and sending push force and / or torque data to the control circuit; andreceiving data at a control circuit for controlling at least one of the rotational speed of the rotational motor and the traverse speed of the traverse motor.

12. The method of claim I I, wherein the control circuit includes a microprocessor and memory with control instructions including a threshold value for the traverse motor sensor.

13. The method of claim 12, further comprising a step of retracting the traverse motor for a determined distance when the traverse sensor threshold value is reached followed by readvancing the traverse motor within the lesion.

14. The method of claim 13, further comprising a step of comparing the speed of rotation of the rotational motor to a rotational motor threshold value and comparing the speed of rotation of the traverse motor to a traverse motor threshold value along with determining a direction of movement of the traverse motor.

15. The method of claim 14, further comprising monitoring the traverse motor torque sensor, the sensor for determining the push force applied by the traverse motor, and the rotational motor speed of the rotational motor with respective threshold values, and retracting the traverse motor and the abrasion element by way of the control circuit based upon the attainment of at least one of the respective threshold values.

16. The method of claim 15, further including a step of pausing rotation of the traverse motor after retraction thereof.

17. The method of claim 16, further comprising readvancing the traverse motor after pausing the traverse motor, thereby readvancing the abrasion element within and along the lesion until a desired treatment is completed without causing any further retraction of the traverse motor based upon an attainment of the respective threshold value for one of the traverse motor torque sensor, the sensor for determining the push force of applied by the traverse motor, and the rotational motor speed of the rotational motor.

18. The method of claim 17, further comprising tracking a rate of change of sensed values of any of the traverse motor torque sensor, the sensor for determining the push force of applied by the traverse motor, and the rotational motor speed of the rotational motor by the control circuit.

19. The method of claim 18, further comprises comparing the rate of change of any one of the traverse motor torque sensor, the sensor for determining the push force of applied by the traverse motor, and the rotational motor speed of the rotational motor to a respective rate of change threshold value and indicating a procedure stop event.

20. The method of claim 19, further comprising stopping the rotation of the rotational motor and retracting the abrasion element from the lesion by moving the traverse motor as controlled by the control circuit.

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