Systems for clot removal and methods of use thereof

Abstract

Disclosed herein are methods, systems, and apparatus, including a non-driven tip including a rotary connector configured to connect a tip to a wire basket, the rotary connector enabling the wire basket to rotate independently of the tip; and the tip affixed to an end of the rotary connector.

Description

Attorney Docket No. 15670-0430W01SYSTEMS FOR CLOT REMOVAL AND METHODS OF USE THEREOFCROSS-REFERENCE TO RELATED APPLICATION

[0001] This application claims the benefit of U.S. Provisional Application No. 63 / 770.462, filed 3 / 12 / 2025. and U.S. Provisional Application No. 63 / 683,006. filed 8 / 14 / 2024, the contents of which are incorporated by reference herein.BACKGROUND

[0002] Thrombectomy devices are medical tools designed to physically remove blood clots from arteries or veins to restore blood flow and prevent serious complications such as stroke, pulmonary embolism, or limb ischemia. In a clinical setting, the procedure is ty pically performed in a catheterization lab or operating room. A catheter is inserted through a small incision and guided to the clot. Mechanical thrombectomy devices are then used to macerate and remove the clot.SUMMARY

[0003] In general, an aspect disclosed herein is a non-driven tip. The non - driven tip includes a rotary connector configured to connect a tip to a wire basket, the rotary connector enabling the wire basket to rotate independently of the tip; and the tip affixed to an end of the rotary connector.

[0004] Examples may include one or more of the following features. The nondriven tip where the rotary connector may include a bearing or a bushing. The rotary connector may include the bearing, the bearing can have a shape which complements a shape of an inner wall of the rotary connector to enable the wire basket to rotate independently of the tip, and where the bearing can be configured to receive an end of the wire basket. The non-driven may include a second bearing engaged to an inner surface of the tip. The rotary connector may include the bushing, and the non-driven tip may include a shaft. The rotary connector may include a pointed insert configured to receive a concave end of the shaft, and the insert can be configured to enable the shaft to rotate independently of the tip and return to a centered position under an azimuthal force. The shaft may include a pointed insert configured to receive a concave insert of the rotary’ connector, and the insert can be configured to enable the shaft to rotate independently of the tip and self-center. The shaft may include a hemispherical end, where the hemispherical end extends into a cavity7of the rotary7connector. The shaft may includeAttorney Docket No. 15670-0430W01 hemispherical end can have a diameter that can be larger than a diameter of a channel into the cavity’. The non-driven tip or claim 9, may include a ball bearing arranged in the cavity. The rotary connector may include a spherical bearing arranged to contact the hemispherical end of the shaft. The shaft may include a spherical end, the rotary connector may include an insert configured to receive the spherical end of the shaft, and the insert can be configured to enable the shaft to rotate independently of the tip. The tip may include a conical profile. The tip may include an elastomer. The tip can be overmolded at least a portion of the rotary connector. The tip may include an inner cavity’ in a first end of the tip, the tip coupled to a center wire. The inner cavity' can have a channel having a diameter that can be narrower than a diameter of a cavity' of the rotary connector. The center wire can be coupled to the inner cavity of the tip. The tip can have a convex surface. The tip can have a concave surface. An outer surface of the tip can be textured.

[0005] In general, an aspect disclosed herein is a method of using a thrombectomy device having a non-driven tip. The method includes disposing a portion of the thrombectomy device within an inner volume of a vasculature such that a non-driven tip of the thrombectomy’ device extends into a clot that restricts flow of a fluid through the inner volume; extending a drive wire of the thrombectomy device within a sheath to cause a wire basket to deploy from a lumen of the sheath and within the clot; rotating the drive wire to cause the wire basket to rotate within the clot; retracting the drive wire within the sheath to cause the wire basket to collapse into a lumen of the sheath; and retracting the portion of the thrombectomy device from the inner volume.

[0006] Examples may include one or more of the following features. The method may include applying a suction to the clot during or after rotating the drive wire. The method may include inflating a balloon of the thrombectomy device during or after rotating the drive wire.

[0007] In general, an aspect disclosed herein is a system. The system includes a thrombectomy device, which includes a flexible, cylindrical sheath configured to be disposed intravenously; a drive wire slidingly disposed within a lumen of the sheath; a drive unit connected to the drive wire; a wire basket connected to the drive wire and opposing the drive unit, the wire basked formed of a memory’ material such that the wire basket collapses into a collapsed configuration when disposed in the lumen, and deploys into an expanded configuration when disposed outside of the lumen; and a non-driven tip configured to rotate independently of the wire basket..Attorney Docket No. 15670-0430W01

[0008] Examples may include one or more of the following features. The system may include a drive unit operably connected to the sheath and drive wire. The drive unit may include a control element configured to slidingly travel the drive wire within the lumen. The drive unit may include a different control element configured to rotate the drive wire within the lumen of the sheath. The system may include a suction port in the non-driven tip, and a tube disposed within the sheath fluidically connecting the suction port to an opposing end of the sheath. The system may include a net connected to the nondriven tip, the net formed of a memory material such that the net collapses into a collapsed configuration when disposed in the lumen, and deploys into an expanded configuration when disposed outside of the lumen. The memory' material may include nitinol. The drive unit can rotate the basket of the thrombectomy device at variable speeds. The thrombectomy device can include a balloon, and a control operable to inflate or deflate the balloon.

[0009] In general, an aspect disclosed herein is a drive unit for a blood clot device. The drive unit includes a sheath slider for adjusting a position, a rotation, or both of a catheter sheath. The drive unit includes a catheter locking slider for locking the position, the rotation, or both of the catheter sheath. The drive unit includes a speed control. The drive unit includes a toggle switch. The drive unit includes a motor.

[0010] Examples may include one or more of the following features. The drive unit where the speed control and the toggle switch are configured for single hand use. The toggle switch and the speed control are on opposing surfaces of the drive unit. The speed control adjusts the rotational speed of a drive wire of the drive unit. The speed control can be continuously variable or variable between discreet speeds.

[0011] The foregoing and other implementations can each optionally include one or more of the following features, alone or in combination.

[0012] The subject matter described in this specification can be implemented in various implementations and may result in one or more of the following advantages.

[0013] Thrombectomy devices including the non-driven tip can safely and effectively remove blood clots while minimizing the risk of the tip breaking off. This provides effective clot removal while enhancing the safety and reliability of the procedure.

[0014] The non-driven tip is produced from medical-grade materials which can increasing slipping between components of the non-driven tip. This can reduce heat generation as the drive wire rotates.Attorney Docket No. 15670-0430W01

[0015] The rotary connector can reduce, e g., minimize, contact area between the non-driven tip and the basket. This can reduce initial torque needed to overcome static friction between the basket and the non-driven tip. This can reduce heat generation during operation and reduce heat-based trauma to the vasculature system.

[0016] The non-driven tip can be decoupled from motion of the drive wire, the wire basket, or both, which can increase the freedom of motion of the non-driven tip in the vasculature system. The non-driven tip can rotate radially or azimuthally independently from other components which increases the ease of advancing the catheter within the vasculature system.

[0017] The design of the coupling of components, e g., the non-driven tip, the wire basket, or a combination of these, allows additional components that enhance thrombectomy to be added to the device (e.g., suction or a non-traumatic embolectomy balloon). This can increase procedure safety, procedure flexibility , and reduce downstream negative effects to the patient.

[0018] The non-driven tip can be added to other types of rotational devices to reduce friction, torque forces, and vascular trauma. This can increase procedure safety for the rotational device including the non-driven tip. This can increase operational flexibility of the non-driven tip in diverse medical procedures, such as nasal, or colon obstruction removal.

[0019] The details of one or more implementations of the subject matter described in this specification are set forth in the accompanying drawings and the description below. Other features, aspects, and advantages of the subject matter will become apparent from the description, the drawings, and the claims.BRIEF DESCRIPTION OF THE DRAWINGS

[0020] FIG. 1 A is an illustration of a thrombectomy device including a non-driven tip and drive unit.

[0021] FIG. IB is an illustration of the non-driven tip and the basket.

[0022] FIG. 1C is an illustration of a cross section of an embodiment of the nondriven tip with a bushing design.

[0023] FIG. ID is an illustration of a cross section view of the drive unit of the thrombectomy device.

[0024] FIG. 2A is an illustration showing an embodiment of the non-driven tip with a ball bearings design.Attorney Docket No. 15670-0430W01

[0025] FIG. 2B is several illustrations showing an exploded view of the nondriven tip and basket of FIG. 2A and an example of basket expansion and operating the non-driven tip.

[0026] FIG. 3A is an illustration showing a side and a cross sectional view of an embodiment of a non-driven tip with a two-component bushing and ribbed over-molding design with a conical end portion.

[0027] FIG. 3B is an illustration showing a side and a cross sectional view of an embodiment of a non-driven tip having a self-centering mechanism as part of the bushing design.

[0028] FIG. 3C is an illustration showing a side and a cross sectional view of an embodiment of the non-driven tip having a bearing ball in connection with the rotary connector.

[0029] FIG. 4A shows a cross sectional illustration of an embodiment of a nondriven tip with a two-piece bushing design and a shortened tip.

[0030] FIG. 4B show s a cross sectional illustration of an embodiment of a nondriven tip having a hollowed rotary connector press fit onto the shaft.

[0031] FIG. 4C show s a cross sectional illustration of an embodiment of a nondriven tip having a rotary connector enclosing a bearing.

[0032] FIG. 5 show s two embodiments of non-driven tips and two heat map images of a computational analysis of tip deformation based on the associated tip design.

[0033] FIG. 6 is a table showing results of percent clot breakage of three different thrombectomy devices.

[0034] FIG. 7 is an illustration showing an embodiment of the non-driven tip with a balloon catheter system.

[0035] FIGS. 8A-8C are illustrations of a thrombectomy device which includes a deployable net and the non-driven tip.

[0036] FIG. 9A is an illustration of an embodiment of the catheter and non-driven tip having an independent rotational element on the drive wire.

[0037] FIG. 9B is an illustration of an embodiment of the non-driven tip in which the rotary connector includes more than one bearing.

[0038] FIG. 10 is a flow chart diagram illustrating a method for creating a shape memory' wire basket.

[0039] Like reference numbers and designations in the various drawings indicate like elements.Attorney Docket No. 15670-0430W01DETAILED DESCRIPTION

[0040] During an endovascular thrombectomy procedure, a catheter of the thrombectomy device is inserted into the vascular system. The catheter is inserted into the vascular system within, before, or just after the tip passes a blood clot. The sheath maintains a wire basket in a collapsed state during insertion and before the sheath is retraced. A slider control retracts the sheath allowing the wire basket to expand into an expanded shape. The basket is rotated to macerate the clot and passed forward and backward to engage as much of the clot as possible. One problem of thrombectomy devices is that the tip may become constricted, pinched, or both, within the vascular system during the thrombectomy procedure. If the tip becomes constricted, pinched, or both, the tip may experience torsion and may break during the rotation due to the resulting shear stresses.

[0041] Described herein is an endovascular thrombectomy (e.g., blood clot removal) device having a non-driven tip which can reduce the risk of tip breakage. The non-driven tip can be connected to the wire basket which can be rotated by a drive unit via the drive wire. The non-driven tip can have a rotational element, e.g.. a bearing or bushing, attached to an end of the non-driven tip which can allow the basket and the nondriven tip to rotate independently. The rotational element can reduce, or prevent, rotation of the non-driven tip when the basket is rotated, when the non-driven tip presses against the walls of the vascular system, or both. Reducing rotation of the non-driven tip reduces breakage during a thrombectomy procedure or any procedure (e.g., atherectomy) where there is a rotational element of the device. The non-driven tip has a molded end portion shaped to move smoothly along a vascular system of a patient. The molded end portion reduces constriction of the non-driven tip when disposed within the vasculature system. The molded end portion can shield the vessel walls, or graft walls, from the internal components of the non-driven tip. This can maintain an atraumatic profile, e.g., a profile which can reduce injury to surrounding tissues, e.g., blood vessels.

[0042] FIG. 1 A illustrates a thrombectomy device 100 including a non-driven tip 110 at an end of a catheter 130 distal from a drive unit 102 of the thrombectomy device 100. The thrombectomy device 100 can be operable to perform thrombectomy procedure on a patient. The thrombectomy device 100 can be operable in a one-hand or a two-hand configuration by a user.

[0043] The drive unit 102 can include a body 112 which can have an ergonomic profile, e.g., a profile which can be shaped to conform to contours of a hand. The bodyAttorney Docket No. 15670-0430W01112 can have an ambidextrous profile such that the thrombectomy device 100 can be operable by a right hand or a left hand of a user. The body 112 can be composed of rigid materials which may conform to one or more certifications which can be required in a healthcare setting.

[0044] The thrombectomy device 100 includes a catheter 130 extending from the drive unit 102. The catheter 130 includes a sheath 136 surrounding a drive wire. The catheter 130 includes a basket 124 connected to a distal end of the drive wire. A nondriven tip 110 is connected to an end of the basket 124 which is opposite the drive wire. The thrombectomy device 100 is shown with one catheter 130, though in some examples, the catheter 130 may be exchanged, e.g., for a different catheter size, a different catheterbased device, or both. This can provide for increased procedural flexibility with the thrombectomy device 100.

[0045] The sheath 136 is slidingly disposable along the length of the drive wire. The sheath control 108 is operable to sliding dispose, e.g., slide, the sheath 136 along the length of the drive wire. The sheath control 108 is operable to slide the sheath 136 to cover or expose the basket 124. The basket 124 enters a collapsed state when the sheath 136 is slid to cover the basket 124, e.g., when the wire basket 124 is within a lumen of the sheath 136. The basket 124 enters an expanded state when the sheath 136 is slid to expose the basket 124. Thus, the sheath control 108 is operable to cause the basket 124 to enter the collapsed or the expanded state. This can provide an operator with increased control over the state of the basket 124. In some examples, the sheath 136 can be partially slid over the basket 124 to partially expose the basket 124. This can place the basket 124 into a state betw een the expanded and the collapsed state, e.g., a reduced expanded state.

[0046] An operator can insert the non-driven tip 110 into the vascular system of a patient, e.g., into a vein or an artery of the patient. The operator can urge the non-driven tip 110 along an interior volume of the vasculature to the location of a complete or partial obstruction, e.g., a thrombosis, e.g., a blood clot.

[0047] In some cases, such as atherectomy, a basket can be designed to shave down atherosclerotic plaque in an artery in a rotational manner. An atherectomy device which can include the non-driven tip can be used with the basket and atherectomy device.

[0048] Larger or smaller examples of the device 100 can use the rotational mechanism of a non-driven tip to clear obstructions in other orifices, e.g., such as nasal (mucous plugging) or the bowel (obstructions due to impaction from feces or foreignAttorney Docket No. 15670-0430W01 material). The design of the non-driven tip can reduce, e.g., prevent, device breakage when in contact with cartilaginous structures of the nasal passage or bowel.

[0049] The operator can urge the non-driven tip 110 through the obstruction. The non-driven tip 110 has a conical profile which reduces drag on the obstruction. The profile also has rounded edges to reduce friction or sticking against a wall of the vasculature. The operator can operate the sheath control 108 to slide the sheath 136 toward the body 112. Sliding the sheath 136 toward the body 112 exposes the basket 124 to the vasculature system.

[0050] The basket 124 enters the expanded state when the sheath 136 exposes the basket 124. The basket 124 is composed of a material which can have a shape memory effect, e.g.. retain a shape memory. The memoiy material can be a metal or a metallic alloy which has the shape memory effect. In some examples, the memoiy material is nitinol. Materials with high elastic moduli like stainless steel can also be used.

[0051] FIG. IB is an illustration of the non-driven tip 110 and the basket 124. The basket 124 includes four wires shaped to provide the basket 124. The basket 124 can include more, or fewer, wires to form the basket 124. A crimp 134 is arranged at opposing ends of the basket 124. The crimp 134 fastens the ends of the wires together. The wires of the basket 124 can be fastened to the drive wire 132 and the non-driven tip 110. The wires of the basket 124 can be permanently, or reversibly, fastened to the drive wire 132. the non-driven tip 110, or both. In some examples, the wires of the basket 124 are affixed, e.g., laser-welded, to the drive wire 132, a shaft 128 of the non-driven tip 1 10, or both.

[0052] The basket 124 can be rotated within the obstruction. Rotating the basket 124 in the obstruction can break down the obstruction, e.g., into smaller pieces. The nondriven tip 1 10 can be configured to decouple from the rotational drive assembly such that it may remain at a substantially fixed angular position while the basket 124 rotates. The non-driven tip 110 can decouple rotational motion from the assembly, e.g., the basket 124, the drive wire 132, or combinations of these, can reduce transmission of torque to the distal end of the catheter 130, and can thereby reduce, e.g., minimize, potential damage to the vasculature.

[0053] The basket 124 can cease rotation. The operator operates the sheath control 108 to slide the sheath 136 along the length of the drive wire 132. The basket 124 can enter the collapsed state as the sheath 136 slides over the basket 124. The operator can withdraw the catheter 130 from the vasculature of the patient.Attorney Docket No. 15670-0430W01

[0054] FIG. 1C is an illustration of a cross section of an embodiment of the nondriven tip 110. The non-driven tip 110 can include materials which are or can be made to be substantially low-friction, smooth, or a combination of these. The non-dnven tip 110 can traverse the vasculature system by at least partially separating motion of the nondriven tip 110 from the basket 124. The motion of at least part of the non-driven tip 110 can be coupled to motion of the drive wire 132 via the basket 124, and the motion of another part of the non-driven tip 110 can be decoupled from motion of the drive wire 132. The non-driven tip 110 can have a diameter which allows accurate placement and reduced friction during translation within the vasculature system, e.g., 1 mm, 2 mm, or less than 3 mm. For applications in larger structures (e.g., bowel) the non-driven tip 110 can be larger, up to 10 mm.

[0055] The non-driven tip 110 includes a shaft 128 which is movable at least partially independently of at least one other part of the non-driven tip 110. In some examples, motion of the shaft 128 is at least partially decoupled from motion of the rotary7connector 122, the tip 120. the connector 126, or combinations of these. The tip 120, rotary connector 122, and connector 126 moving at least partially independent of the shaft 128 can allow the drive wire 132 to induce motion in the basket 124 and shaft 128 while reducing, or preventing, motion of one or more of the tip 120, rotary7connector 122, or connector 126. The shaft 128 may have a length in a range from 0.5 inches to 0. 12 inches, e.g., 0.0984 inches, although this value can be varied. Reducing the length of the shaft 128, reducing the length of the rotary connector 122, or both, can reduce the friction within the non-driven tip 110, and can increase the movement independence between the shaft 128, rotary connector 122, the tip 120, or a combination of these.

[0056] An end of the rod 128 extends into a rotary connector 122. The rotary connector 122 of FIG. 1C is a bushing, though other examples of rotary connector 122 are described herein, such as one or more bearings. The shaft 128 has a flared end 129. The flared end 129 is wider than an opening of the rotary7connector 122. The end 129 prevents the rotary connector 122 and tip 120 from separating from the basket 124. The end 129 can be rounded, e.g., like a ball, or a hemisphere, to reduce, e.g.. prevent, separation of the shaft 128 and the rotary connector 122, facilitate smoother motion within the non-driven tip 110, or both. The rotary connector 122 can be composed of low friction materials, e.g., smooth polished 304 stainless steel, titanium, acetal, polyether ether ketone (PEEK), polytetrafluoroethylene (PTFE), or high-density polyethylene (HDPE). The rotary connector 122 can reduce, e.g., minimize, contact area between theAttorney Docket No. 15670-0430W01 non-driven tip 110 and the wire basket 124, which can reduce initial torque needed to overcome static friction between the bushing and the shaft 128. In some examples, the rotary connector 122 can include a shoulder on the inside of the bushing component which can limit the depth of insertion of the silicone holder, reduce manufacturing complexity, or reduce surface contact area and thus friction between the end 129 and the rotary connector 122, or a combination of these. Medical grade lubricants (e.g.. water-, silicone-, or perfluoropolyether (PFPE)-based lubricants) can be introduced between one or more components of the non-driven tip 110, e.g., between the rotary connector 122 and the end 129, which can reduce friction, improve heat dissipation, or both.

[0057] The rotary connector 122 and the shaft 128 can rotate independently . The rotary connector 122 can have an opening that has a larger diameter than a diameter of the shaft 128 and less than a diameter of the end 129. Thus, rotation of the tip 120 and rotation of the shaft 128 are unlinked allowing rotation of each without corresponding rotation of the other.

[0058] The rotary connector 122 can be affixed to the tip 120 by a connector 126. The connector 126 affixes the tip 120 to the rotary connector 122. The connector 126 can affix the rotary connector 122 to the tip 120 permanently, or reversibly. The connector 126 affixes the tip 120 to the rotary7connector 122 such that the tip 120 and the rotary7connector 122 can remain in a fixed orientation with respect to one another, e.g., at a fixed rotational orientation. The connector 126 can be a metal, plastic, elastomer, or a combination of these. The connector 126 and the tip 120 can be co-molded, press fit, or cast together to fix the tip 120 to the connector 126.

[0059] The rotary connector 122 can be shaped to be slid within the sheath 136, e.g., the rotary connector 122 can have a diameter which is less than the sheath 136. In some examples, the rotary connector 122 can be shaped to have a substantially similar diameter to the sheath 136, e.g., such that there is little to no gap bet veen an inner surface of the sheath 136 and the outer surface of the rotary connector 122 when the sheath 136 is slid over the rotary connector 122.

[0060] The tip 120 can be generally shaped to traverse a vasculature system, e.g.. can be cylindrical. The tip 120 can include an end portion 138 yvhich has a profiled to reduce friction yvith an interior yvall of the vasculature system. The end portion 138 can include a rounded profile, a bullet-like profile, a smooth profile, a symmetric profile, an asymmetric profile, or a combination of these.Attorney Docket No. 15670-0430W01

[0061] The tip 120 is composed of a material which has a relatively soft, relatively smooth, or both, surface to reduce friction against the interior wall of the vasculature system. In some examples, the material of which the tip 120 is composed includes an elastomer, e.g., silicone.

[0062] FIG. ID is an illustration of a cross section view of the drive unit 102 of the thrombectomy device 100. The drive unit 102 includes one or more controls for an operator to manipulate parts of the thrombectomy device 100. perform the thrombectomy procedure, or both. The drive unit 102 can include a locking control 106, a sheath control 108, or both, to control one or more of the drive wire 132, or the sheath 136.

[0063] The locking control 106 and the sheath control 108 are mechanical components that can control the positioning and deployment of one or more components of the thrombectomy device 100. The sheath control 108 can be operated to slide, e.g., advance or retreat, the sheath 136 along the drive wire 132. The locking control 106 can be operated to lock the sheath 136 in place, e.g., in one position. In some examples, the locking control 106 can be operable to lock the sheath 136 in place when the basket 124 is in the expanded state, or when the basket 124 is in the collapsed state. The locking control 106 can be used to unlock the catheter 136 and replace it with another catheter, with a larger or smaller basket 124, for a different type of thrombectomy or atherectomy device, or a combination of these.

[0064] The drive wire 132 is a flexible body which can allow the sheath 136 and the non-driven tip 1 10 to be guided into or through the vasculature system. The drive wire 132 connects the basket 124 to a motor 116 through gearing 117.

[0065] The drive unit 102 is operable to selectively rotate the basket 124 by an operator through operation of one or more of the controls. The motor 116 rotates the drive wire 132 via the gearing 117 according to the desired speed set by the speed switch 104 and the state of the toggle switch 114. The toggle switch 114 can be operated to change an operating state of the motor, e.g., an on state or an off state. The speed switch 104 can be operated to change a speed at which the motor 116 operates, e.g., a three-way switch can change the speed of the motor 116 between a comparatively high, medium, or low speed. In some examples, the speed switch 104 is a continuous, or an analog switch. The toggle switch 114 can be positioned to be operable according to different operator grips. In some examples, the toggle switch 114 can be positioned to be operable using a middle, or an index finger, of an operator.Attorney Docket No. 15670-0430W01

[0066] A variable speed drive unit 102 can be operated at a varying range of revolutions per minute (RPM) to increase or decrease the rotation rate of the basket 124 continuously. Lower speeds can be used for specific areas of the vasculature system, e.g., the arterial end or areas in which there can increased torque on the tip. Lower speeds can reduce tip interaction with the vasculature or other tubular structures to reduce damage to the vasculature system, instances of tip damage or breaking, or a combination of these. In some examples, the drive unit 102 is operable in a range from 2000 RPM to 10000 RPM (e.g., 3700 RPM to 5000 RPM, 3000 RPM to 6000 RPM, or 3700 RPM to 4100 RPM).

[0067] The materials described herein for one or more components of the thrombectomy device 100 may conform to one or more certifications to meet one or more hygiene, biocompatibility, durability standard which can be required in a healthcare setting. Examples can include, but are not limited to, medical-grade metals or metallic alloys (e.g., titanium, brass, or stainless steel), medical-grade plastics, medical -grade polymers (e.g., poly ether ether ketone (PEEK), polytetrafluoroethylene (PTFE), high- density polyethylene (HDPE), polyoxymethylene (POM, or POM-H, e.g., acetal, or polyacetal)), or medical-grade elastomers (e.g., silicone, thermoplastic elastomer (TPE), or poly dimethylsiloxane (PDMS)).

[0068] FIG. 2A is an illustration showing an embodiment of the non-driven tip 210. The non-driven tip 210 is shown connected to the catheter 130 via the basket 124 and the crimps 134. The non-driven tip 210 includes an embodiment of the rotary connector 122, e.g., the rotary connection 222. The rotary connection 222 can include one or more bearings, e.g., bearings 223. The rotary connection 222 contains two bearings 223. The bearings 223 are enclosed within the rotary' connection 222 to enable the tip 220 to move, e.g., rotate independently of the basket 124.

[0069] FIG. 2B is several illustrations showing an exploded view of the nondriven tip 210 and catheter 130 of FIG. 2A and an example of operating the non-driven tip 210, e.g., to operate the non-driven tip 210 in a thrombectomy procedure. From left to right, the first image depicts the non-driven tip 210 and the catheter 130 in a state in which the sheath 136 is extended to adjoin the non-driven tip 210. The wire basket 124 is in the collapsed state within the sheath 136. An operator can position the non-driven tip 210 near (e.g., adjacent to) a thrombectomy during the thrombectomy procedure. The non-driven tip 210 can be positioned proximal to, within, or distal to, the thrombus or obstructive material with respect to the drive unit 102, e.g., before, within or past theAttorney Docket No. 15670-0430W01 thrombus or obstructive material within the vasculature system, or any tubular system (e.g., nasal canal, bowel).

[0070] The second part of the operation process (FIG. 2B) depicts the catheter 130 translated toward the back of the drive unit 102 along the drive wire 132, e.g., such as if an operator operates the sheath control 108. The wire basket 124 is shown in the expanded state when exposed by translation of the sheath 136. The wire basket 124 in the expanded position may press against the inner walls of the vasculature system during a thrombectomy procedure.

[0071] The third image of the operation process (FIG. 2B) depicts the wire basket 124 rotating independently from the sheath 136 and the non-driven tip 210. The drive wire 132 (not shown) is rotated by the drive unit 102. The wire basket 124 is connected to the drive wire 132 and rotates when the drive wire 132 rotates. The non-driven tip 210 can remain in a substantially fixed position, e.g., rotational position, when the wire basket 124 rotates.

[0072] An operator may perform the steps depicted in the first through third images in reverse order to remove the non-driven tip 210 from the vasculature system and end the thrombectomy procedure. The drive unit 102 can stop rotating the drive wire 132 (e.g., if the operator operates the drive unit 102 to stop rotating the drive wire 132). The sheath 136 can be translated toward the non-driven tip 210. The wire basket 124 can enter the collapsed state as the sheath 136 translates toward the non-driven tip 210. The catheter 130 can be removed from the vasculature system to withdraw the non-driven tip 210.

[0073] FIG. 3A is an illustration showing a side and a cross sectional view of an embodiment of a non-driven tip 310 having a conical end portion 338 with a rotary connector 316 and a shaft 318. The non-driven tip 310 can be produced without a connector 126 and can reduce the assembly complexity of the driven tip, w hich can reduce production cost. The conical end portion 310 facilitates smooth, e.g., low friction, navigation through a vessel, can minimize resistance during advancement through an obstruction, e.g.. a thrombus, and can reduce the risk of vessel wall damage.

[0074] FIG. 3B is an illustration showing a side and a cross sectional view of an embodiment of a non-driven tip 320 having an extended tip 322 and a rotary connection 326 in which an end of the shaft 328 includes a concave surface. The concave surface of the shaft 328 mates with a convex end portion of the connector 324. In some examples, the concave surface and the convex end portion are shaped to be mated w hich canAttorney Docket No. 15670-0430W01 increase the rotational freedom of the rotary connection 326. In some examples, the concave surface and the convex end portion can be designed to provide self-centering properties to the tip when force is applied through the shaft azimuthally, e.g., towards the drive unit, along the drive wire 132, or both.

[0075] FIG. 3C is an illustration showing a side and a cross sectional view of an embodiment of the non-driven tip 310 having a bearing 314 in connection with the rotary’ connection 316. The bearing 314 can contact an end of the shaft 318. The end of the shaft 318 is hemispherical and the bearing 314 is spherical which can reduce, e.g., minimize, friction between the end of the shaft 328 and the bearing 314. This can reduce motion transfer between the shaft 318 and the tip 312. The bearing 314 can reduce the cost of materials and manufacturing. The end of the shaft 318 is hemispherical, and the bearing 314 is spherical, creating a ball-on-ball interface that minimizes friction between the shaft 318 and the bearing 314. This design can reduce motion transfer between the shaft 318 and the tip 312, which can enhance rotational smoothness and reduce unwanted movement.

[0076] FIG. 4A shows a cross sectional illustration of an embodiment of a nondriven tip 410. The non-driven tip 410 includes a tip 412 over-molded onto the rotary' connector 414. The rotary’ connector 414 includes a textured end portion 418. The tip 412 is over-molded onto the end portion 418. The textured end portion 418 increases adhesion between the tip 412 and the rotary connector 414 which may reduce tip breakage. The shaft 416 includes a hemispherical end portion which is arranged in the bushing of the rotary' connector 414.

[0077] FIG. 4B shows a cross sectional illustration of an embodiment of a nondriven tip 420 having a rotary connector 424 press fit onto an insert 428. The rotary’ connector 424 includes the insert 428 which is shaped to include a channel 426. The insert 428 is shaped to be arranged into the rotary connector 424. The channel 426 can be shaped to receive one or more wires extending from the basket 124, or a portion of a crimp 134. The insert 428 can be injection molded from plastic, which can reduce manufacturing costs. The insert 428 can connect to one or more wires of the basket 124, which can reduce the number of connection points between the non-driven tip 420 and the basket 124, which can reduce the risk of failure. The non-driven tip 420 includes a tip 422 which is pre-cast and can be inserted into an opening of the rotary' connector 424 in an end opposing the wire basket 124. The tip 422 can be decoupled from the rotaryAttorney Docket No. 15670-0430W01 connector 424 with the addition of lubrication, the use of a plastic with a higher stiffness, the addition of a reinforcing wire in the center, or combination.

[0078] FIG. 4C shows a cross sectional illustration of an embodiment of a nondriven tip 430 having a rotary connector 436 enclosing a bearing 438. The non-driven tip 430 can use injection molding to reduce machining during manufacturing. The bearing 438 can be a unitary body attached to, e.g., over molded onto, one or more wires of the wire basket 124. The bearing 438 can be welded, connected with an adhesive, overmolded, press-fit, or any combination of these or alternative known in the field, to the wires of the wire basket 124.

[0079] The shape of the outer surface of the bearing 438 is complementary to the shape of an inner surface of the rotary connector 436. The rotary connector 436 can be manufactured separately, e.g., injection molded, and arranged to surround the bearing 438 to provide a bushing. The tip 432 can be formed, e.g., over-molded, onto the rotary7connector 436 to provide the non-driven tip 430.

[0080] The complementary7shapes of the rotary connector 436 and the bearing 438 can allow motion of the bearing 438 to be decoupled from motion of the rotary connector 436. In some examples, the bearing 438 and the shape of the inner surface of the rotary7connector 436 can be cylindrical. The cylindrical shapes can facilitate decoupling rotational motion of the bearing 438 and the rotary connector 436. The tip 432 can be connected with an adhesive, over-molded, or any combination of these or alternative known in the field, to the rotary connector 436.

[0081] The tip 432 is attached, e.g., over-molded, to the rotary7connector 434 on a textured end region 436. The texturing of the end region 436 includes a series of channels into an outer surface of the rotary connector 434, which can provide geometric constraints to reduce, e.g., prevent, axial slippage of the over molded material.

[0082] FIG. 5 shows two embodiments of non-driven tips and two heat map images of a computational analysis of tip deformation based on the associated tip design. Computational methods (e.g., finite element analysis (FEA) was used to model stresses in example non-driven tip 110 designs. The desrgns were modeled to determrne whether they achieve one or more expected criterion, e.g., a stress criterion, that the non-driven tip may experience during use.

[0083] In some examples, breakage occurs when the molded tip separates from the rotary connection. Stress forces were modeled for two tip designs. A first tip 510 having a splined bushing connecting the tip to the rotary connection was modeled. TheAttorney Docket No. 15670-0430W01 modeling results are shown as the heat-map below tip 510. The results show that the area of highest stress (marked) achieve the expected stress criterion which can indicate reduced tip breakage, e.g., were less than a maximum stress criterion, e.g., above an adhesion criterion indicating a low chance of the molded tip separating from the bushing compared to traditional designs.

[0084] A second tip 520 having rounded-spline bushing connecting the tip to the rotary connection was modeled. The modeling results are shown as the heat-map below tip 520. The non-driven tip 110 can achieve substantially similar performance compared to design 1 and design 2. The results show that the area of highest stress (marked) achieve the expected stress criterion which can indicate reduced tip breakage compared to traditional designs.

[0085] FIG. 6 is a table showing results of percent clot breakage of three thrombectomy tip designs. Design 1 and design 2 are existing tips known in the art. Design 3 is an embodiment of the non-driven tip 110. The three designs were used in a test-bed experimental setup in which artificially created clots of approximately 0.3'’ diameter and 1” long were macerated using a thrombectomy device including a tip from one of designs 1, 2, or 3. A computer vision system was used to perform computational visual analysis of the number of clot fragments and the size of clot fragments generated by the thrombectomy device.

[0086] Inset to FIG. 6 is a line chart comparing density of clots, e.g., number of clots, to clot diameter (mm) for each of tip designs 1 , 2, and 3. Percentage of clot breakage can be an indicator of effectiveness of a device, e.g., clot fragments under 2 mm can be more easily absorbed by the lungs. The percentage of clot breakage to sizes under 2 mm was determined as an indication for the effectiveness of the device to reduce the risk for adverse complications. The line chart compares the distribution of clot fragment size after normalization to the total number of clot fragments produced by each design tested. In the table, “count"’ is the number of clot fragments detected by the computer vision system, and “min” and “max” describe the minimum and maximum sized clot fragment measured by the system. Design 3. e.g., the non-driven tip, was shown to be at least comparable to design 1 and design 2 based on the line chart and tables of results.

[0087] The non-driven tip 110 can be included in multiple catheter systems which can enhance the effectiveness of a thrombectomy procedure. FIG. 7 is an illustration showing an embodiment of the catheter 130 including the non-driven tip 110, the wire basket 124, and a balloon 700, e.g., a balloon catheter system, or a non-traumaticAttorney Docket No. 15670-0430W01 embolectomy balloon. A balloon catheter system can stop, e.g., temporarily stop, blood flow in the target vessel during clot retrieval. Including the non-driven tip 110 in a balloon catheter system can reduce distal embolization, e.g., can reduce the likelihood that a clot fragment is carried downstream. In some examples, the balloon can be used to perform mechanical embolectomy of an arterial plug.

[0088] The rotational motion of the drive wire 132 and wire basket 124 can be isolated from the non-driven tip 110 and the balloon 700. The drive wire 132 can pass through the balloon 700. The balloon can be connected to a catheter that does not rotate. The balloon 700 can press against the inner walls of the vasculature system when in a deployed state. The wire basket 124 can rotate while the balloon 700 remains in place against the inner walls and the non-driven tip 110 remains in the substantially same position. The drive unit 102 can include a control for inflation and deflation of the balloon 700. The balloon catheter system can include a tube disposed within the sheath of the suction catheter. The tube can fluidically connect the balloon to an opposing end of the sheath, e.g., to the drive unit 102. The tube can allow a fluid, e.g.. a gas or liquid, to inflate or deflate the balloon 700.

[0089] The non-driven tip 110 can be included in a suction catheter system, e.g., an aspiration catheter. The suction catheter system can include a suction port 710. The drive unit can include a control operable to apply a negative pressure to the suction port 710. The negative pressure can aid removal of clots or other obstructions. In some examples, the suction port 710 is arranged at an end of the non-driven tip 1 10. The suction catheter system can include a tube disposed within the sheath of the suction catheter. The tube can fluidically connect the suction port to an opposing end of the sheath, e.g., to the drive unit 102.

[0090] The non-driven tip 110 can be arranged near the clot and negative pressure applied to the suction catheter system. Rotational motion of the suction catheter system can be decoupled from motion of the non-driven tip 110 w hich enhances the effectiveness of the suction catheter system without causing motion-based trauma to the vasculature system near the non-driven tip 110. The drive unit 102 can include a control to apply a negative pressure to the suction port.

[0091] FIGS. 8A-8C are illustrations of a thrombectomy device 800 having a catheter 830 which includes a deployable net 852 between the non-driven tip 110 and the wire basket 824. The net 852 between the non-driven tip 110 and the wire basket 124 can improve the safety and efficacy of thrombectomy procedures. The net 852 can captureAttorney Docket No. 15670-0430W01 clots or clot fragments during a thrombectomy procedure, which prevents distal clot embolization.

[0092] The sheath control 108 of the drive unit 102 can be operated to control the state of the shaft 128 and the net 852. The sheath control 108 can be operated to retract the sheath 136 toward the drive unit 102. Fully retracting the sheath 136 can deploy the net 852 and allow the wire basket 124 to enter the expanded state. The net 852 being in the expanded state can allow clots or other obstructions to be captured in the net 852.

[0093] The sheath control 108 can be operated to partially advance the sheath 136. The sheath control 108 partially advancing the sheath 136 can withdraw the net 852 to a collapsed state, e.g., collapsed around the drive wire 132. The sheath 136 can be advanced completely to the non-driven tip 110 which causes the wire basket 124 to enter the collapsed state. Withdrawing the catheter 130 can withdraw clots or other obstructions captured within the net 852 during a procedure e.g., thrombectomy, rotational aspiration, etc.

[0094] FIG. 9A is an illustration of an embodiment of the catheter 130 and nondriven tip 110 having a rotational element 902 between the drive unit 102 and the wire basket 124. The catheter 130 includes the rotational element 902 on the drive wire 132 within the sheath 136. The rotational element 902 can reduce friction between the drive wire 132 and the sheath 136 which can reduce heat generated during a thrombectomy procedure.

[0095] FIG. 9B is an illustration of an embodiment of the non-driven tip 1 10 in which the rotary connector 922 includes more than one, e.g., two, bearings. The bearings are separated by crimping beads which are attached to an inner wire 924. The inner wire 924 extends into the tip 120. The rotary connector 922 can be crimped to an end of the wire basket 124. Rotation of the wire basket 124 can rotate the rotary connector 122. The bearings attached to the inner wire 924 decouple rotation of the rotary connector 922 from the tip 120. The enclosed bearing design 922 can reduce friction, heat generation, or both, between the rotary connector 922 and the ball bearings.

[0096] A method 1000 for creating a wire basket 124 is disclosed herein. The method 1000 can be performed to create a shape memory wire basket 124 which can be used with a thrombectomy device 100 described herein. FIG. 10 is a flow chart diagram illustrating the method 110 for creating the wire basket 124.

[0097] One or more wires are provided (1002). The wires are composed of a shape memory material. The shape memory material can have a critical temperature, e.g..Attorney Docket No. 15670-0430W01 a transition temperature, at which the material undergoes a phase change. At temperatures below the critical point temperature the material can be deformable.

[0098] The one or more wires are secured to a basket blank (1004). The basket blank can have a shape which defines the basket shape when the wires are secured to the basket blank. In some examples, the basket blank can have a curved shape, e.g., a football-like shape. In some examples, the basket blank can have a number of channels in an outer surface corresponding to positions at which the one or more wires are secured. In some examples, the number of wires is four and the basket blank has four channels evenly spaced around the long axis of the football-like basket blank. The one or more wires can be crimped before, or after, the wires are secured to the basket blank. The basket blank can be composed of a material that is stable above the critical temperature of the shape memory material, e.g., can be composed of steel.

[0099] The one or more wires secured to the basket blank are heated to a temperature at or above the critical temperature (1006). In some examples, the one or more wires secured to the basket blank can be heated in a furnace. Heating the one or more wires to at or above the critical temperature can cause the shape memory material to retain the shape held during heating, e.g., retain the shape when cooled.

[0100] After heating the one or more wires to, or above, the critical temperature, the wires may be cooled in a controlled manner, such as by quenching in cool water or allowing a defined air-cooling rate, to facilitate retention of the desired shape and mechanical properties. This method can be useful for rapid prototyping, as it allows different basket geometries to be fabricated quickly by producing and swapping out various basket blanks, without requiring new wire-handling or forming equipment.

[0101] Particular implementations have been described. Other implementations are within the scope of the following claims. For example, the operations recited in the claims, described in the specification, or depicted in the figures can be performed in a different order and still achieve desirable results.

Claims

Attorney Docket No. 15670-0430W01WHAT IS CLAIMED IS:1 . A non-driven tip comprising: a rotary connector configured to connect a tip to a wire basket, the rotary connector enabling the wire basket to rotate independently of the tip; and the tip affixed to an end of the rotary connector.

2. The non-driven tip of claim 1, wherein the rotary connector comprises a bearing or a bushing.

3. The non-driven tip of claim 2, wherein the rotary connector comprises the bearing, the bearing has a shape which complements a shape of an inner wall of the rotary connector to enable the wire basket to rotate independently of the tip, and wherein the bearing is configured to receive an end of the wire basket.

4. The non-driven of claim 2 or claim 3, comprising a second bearing engaged to an inner surface of the tip.

5. The non-driven of any one of claim 2 to claim 4, wherein the rotary connector comprises the bushing, and the non-driven tip includes a shaft.

6. The non-driven tip of claim 5, wherein the rotary connector comprises a pointed insert configured to receive a concave end of the shaft, and the insert is configured to enable the shaft to rotate independently of the tip and return to a centered position under an azimuthal force.

7. The non-driven tip of claim 5 or claim 6, wherein the shaft comprises a pointed insert configured to receive a concave insert of the rotary connector, and the insert is configured to enable the shaft to rotate independently of the tip and self-center.

8. The non-driven tip of any one of claim 5 to claim 7, wherein the shaft includes a hemispherical end, wherein the hemispherical end extends into a cavity of the rotary connector.Attorney Docket No. 15670-0430W019. The non-driven tip of claim 8, wherein the shaft comprises hemispherical end has a diameter that is larger than a diameter of a channel into the cavity.

10. The non-driven tip of claim 8 or claim 9, comprising a ball bearing arranged in the cavity.

11. The non-driven tip of claim 10, wherein the rotary connector comprises a spherical bearing arranged to contact the hemispherical end of the shaft.

12. The non-driven tip of any one of claim 8 to claim 11, wherein the shaft comprises a spherical end, the rotary connector comprises an insert configured to receive the spherical end of the shaft, and the insert is configured to enable the shaft to rotate independently of the tip.

13. The non-driven tip of any one of claim 1 to claim 12, wherein the tip includes a conical profile.

14. The non-driven tip of any one of claim 1 to claim 13, wherein the tip comprises an elastomer.

15. The non-driven tip of claim 14, wherein the tip is over-molded at least a portion of the rotary' connector.

16. The non-driven tip of any one of claim 1 to claim 15, wherein the tip comprises an inner canty in a first end of the tip, the tip coupled to a center wire.

17. The non-driven tip of claim 16, wherein the inner cavity’ has a channel having a diameter that is narrower than a diameter of a cavity’ of the rotary’ connector.

18. The non-driven tip of claim 16 or claim 17, wherein the center wire is coupled to the inner cavity’ of the tip.

19. The non-driven tip of any one of claim 1 to claim 18, wherein the tip has a convex surface.Attorney Docket No. 15670-0430W0120. The non-driven tip of any one of claim 1 to claim 19, wherein the tip has a concave surface.

21. The non-driven tip of any one of claim 1 to claim 20, wherein in an outer surface of the tip is textured.

22. A method of using a thrombectomy device having a non-driven tip, comprising: disposing a portion of the thrombectomy device within an inner volume of a vasculature such that anon-driven tip of the thrombectomy device extends into a clot that restricts flow of a fluid through the inner volume; extending a drive wire of the thrombectomy device within a sheath to cause a wire basket to deploy from a lumen of the sheath and within the clot; rotating the drive wire to cause the wire basket to rotate within the clot; retracting the drive wire within the sheath to cause the wire basket to collapse into a lumen of the sheath; and retracting the portion of the thrombectomy device from the inner volume.

23. The method of claim 22, comprising applying a suction to the clot during or after rotating the drive wire.

24. The method of claim 22 or claim 23, comprising inflating a balloon of the thrombectomy device during or after rotating the drive wire.

25. A system, comprising: a thrombectomy device, comprising: a flexible, cylindrical sheath configured to be disposed intravenously; a drive wire slidingly disposed within a lumen of the sheath; a drive unit connected to the drive wire; a wire basket connected to the drive wire and opposing the drive unit, the wire basked formed of a memory material such that the wire basket collapses into a collapsed configuration when disposed in the lumen, and deploys into an expanded configuration when disposed outside of the lumen; and a non-driven tip configured to rotate independently of the wire basket.Attorney Docket No. 15670-0430W0126. The system of claim 25, comprising a drive unit operably connected to the sheath and drive wire.

27. The system of claim 26, wherein the drive unit comprises a control element configured to slidingly travel the drive wire within the lumen.

28. The system of claim 27, wherein the drive unit comprises a different control element configured to rotate the drive wire w ithin the lumen of the sheath.

29. The system of any one of claim 25 to claim 28, comprising a suction port in the non-driven tip, and a tube disposed within the sheath flui dically connecting the suction port to an opposing end of the sheath.

30. The system of any one of claim 25 to claim 29, comprising a net connected to the non-driven tip. the net formed of a memory material such that the net collapses into a collapsed configuration when disposed in the lumen, and deploys into an expanded configuration w hen disposed outside of the lumen.

31. The system of claim 30, wherein the memory material comprises nitinol.

32. The system of any one of claim 25 to claim 31, w herein the drive unit can rotate the basket of the thrombectomy device at variable speeds.

33. The system of any one of claim 25 to claim 31, wherein the thrombectomy device comprises a balloon, and a control operable to inflate or deflate the balloon.

34. A drive unit for a blood clot device, comprising: a sheath slider for adjusting a position, a rotation, or both of a catheter sheath; a catheter locking slider for locking the position, the rotation, or both of the catheter sheath; a speed control; a toggle switch; and a motor.Attorney Docket No. 15670-0430W0135. The drive unit of claim 35, wherein the speed control and the toggle switch are configured for single hand use.

36. The drive unit of claim 36, wherein the toggle switch and the speed control are on opposing surfaces of the drive unit.

37. The drive unit of any one of claim 35 to claim 37, wherein the speed control adjusts the rotational speed of a drive wire of the drive unit.

38. The drive unit of any one of claim 35 to claim 38, wherein the speed control is continuously variable or variable between discreet speeds.

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