INTRAVASCULAR THROMBECTOMY DEVICE AND PROCESS FOR TREATING ACUTE ISCHEMIC STROKE

Abstract

An intravascular thrombus retraction device includes: wires that are compressible into a compact cylindrical form within a catheter and are self-expandable into a wire mesh web with at least some parallel wires forming openings in the wire mesh sufficient to allow fluid passage and small enough to filter particles of at least 0.001 mm, a base of the wire mesh web connected to radial ring-shaped structure supporting and maintaining an opening in the base of the wire mesh and forming a thrombus capture volume, and the radial ring-shaped structure being compressible into the catheter and being self-expandable or expandable by struts when free of compressive forces within the catheter to open up into an open, expanded, radial ring-shaped structure which maintains the opening in the opening in the base of the wire mesh.

Claims

1. A method of removing a blood clot from a position within a blood vessel comprising: inserting a delivery catheter into a region within the blood vessel without passing the position of the blood clot, the delivery catheter comprising an exterior catheter, and a deployment catheter as an interior catheter within a lumen of the exterior catheter; the deployment catheter comprises: a. the interior catheter with a second lumen, and within the second lumen in linear orientation within the second lumen are three separate and distinct compressed and expandable mesh elements connected by at least two struts passing along a surface of a middle one of the compressed and expandable mesh elements; b. the at least two struts having elastic memory sufficient to expand themselves and provide expansion forces on the three separate and distinct compressed and expandable mesh elements; c. a most distal one of the three separate and distinct compressed and expandable mesh elements having an opening which faces towards the interior catheter and the middle one of the three separate and distinct compressed and expandable mesh elements after the most distal one of the compressed and expandable mesh elements is deployed and expands; d. a most proximal one of the three separate and distinct compressed and expandable mesh elements having an opening which faces away from the interior catheter and towards the middle one of the three separate and distinct compressed and expandable mesh elements after the most proximal one of the compressed and expandable mesh elements is deployed and expands; the method further comprising extending the deployment catheter past the clot while the exterior catheter does not pass the position of the blood clot; once a leading end of the deployment catheter has passed the position of the blood clot, deploying only the most distal one of the three separate and distinct compressed and expandable mesh elements past the position of the blood clot, while the middle one of and the most proximal one of the three separate and distinct compressed and expandable mesh elements remain between the clot and the interior catheter; the at least two struts expanding to expand all of the three separate and distinct compressed and expandable mesh elements; withdrawing the most distal one of the three separate and distinct compressed and expandable mesh elements towards the blood clot and supporting it on or within the opening which faces towards the interior catheter and the middle one of the three separate and distinct compressed and expandable mesh elements, and bringing the most distal mesh element and the middle one of the mesh elements together, with the blood clot stabilized between the most distal mesh element and the middle mesh element; bringing the stabilized blood clot and the most distal mesh element and the middle one of the mesh elements towards the most proximal of the three separate and distinct compressed and expandable mesh elements; at least partially withdrawing the deployment catheter into the exterior catheter; and withdrawing the delivery catheter from the blood vessel along with the blood clot.

2. The method of claim 1 wherein bringing the stabilized blood clot and the most distal mesh element and the middle one of the mesh elements towards the most proximal of the three separate and distinct compressed and expandable mesh elements; at least partially withdrawing the deployment catheter into the exterior catheter; and withdrawing the delivery catheter from the blood vessel along with the blood clot are performed sequentially.

3. The method of claim 1 wherein bringing the stabilized blood clot and the most distal mesh element and the middle one of the mesh elements towards the most proximal of the three separate and distinct compressed and expandable mesh elements; at least partially withdrawing the deployment catheter into the exterior catheter; and withdrawing the delivery catheter from the blood vessel along with the blood clot are performed contemporaneously.

4. The method of claim 1 wherein a surface of the middle mesh element conformed against a surface of the most distal mesh element.

5. The method of claim 1 wherein there are at least three struts with elastic memory deployed from the interior catheter.

6. The method of claim 1 wherein the opening in the most distal one of the mesh elements forms a surface that is not orthogonal to surfaces within the blood vessel.

7. The method of claim 1 wherein a distal face of the middle one of and the most proximal one of the three separate and distinct compressed and expandable mesh elements has an additional expandable and deflateable element attached thereto, which is expandable and deflateable by external controls, and after deployment and expansion of the middle one of the expandable mesh elements, the front face of the additional expandable and deflatable element is expanded and deflated to apply force against the clot to assist in reducing total volume of the clot.

8. The method of claim 7 wherein the front face of the additional expandable and deflatable element is repeatedly expanded and deflated.

9. The method of claim 7 wherein the front face of the additional expandable and deflatable element has at least one protuberance, prongs, projection, blade or edge to assist in disrupting the clot.

10. The method of claim 8 wherein a region surrounding the clot within the blood vessel is non-invasively observed to determine a largest space between the clot and an interior wall of the blood vessel, and the leading end of the deployment catheter is passed through the largest space between the clot and the interior wall of the blood vessel until the leading end of the deployment catheter is past the position of the blood clot.

11. The method of claim 9 wherein a region surrounding the clot within the blood vessel is non-invasively observed to determine a largest space between the clot and an interior wall of the blood vessel, and the leading end of the deployment catheter is passed through the largest space between the clot and the interior wall of the blood vessel until the leading end of the deployment catheter is past the position of the blood clot.

12. A device for the removal of a thrombus from a blood vessel having a delivery catheter as an exterior catheter comprising: a) a deployment catheter within a first lumen of the exterior catheter, the deployment catheter comprising: i ) an interior catheter with a second lumen, and within the second lumen in linear orientation within the second lumen are three separate and distinct compressed and expandable mesh elements connected by at least two struts passing along a surface of a middle one of the compressed and expandable mesh elements; ii) the at least two struts having elastic memory sufficient to expand themselves and provide expansion forces on the three separate and distinct compressed and expandable mesh elements; iii) a most distal one of the three separate and distinct compressed and expandable mesh elements having an opening which faces towards the interior catheter and the middle one of the three separate and distinct compressed and expandable mesh elements after the most distal one of the compressed and expandable mesh elements is deployed and expands; and iv) a most proximal one of the three separate and distinct compressed and expandable mesh elements having an opening which faces away from the interior catheter and towards the middle one of the three separate and distinct compressed and expandable mesh elements after the most proximal one of the compressed and expandable mesh elements is deployed and expands.

13. The device of claim 12 wherein there are at least three and fewer than six struts having elastic memory sufficient to expand themselves and provide expansion forces on the three separate and distinct compressed and expandable mesh elements.

14. The device of claim 12 wherein the middle one of the three separate and distinct compressed and expandable mesh elements has mesh surfaces in both a proximal face and a distal face when expanded.

15. The method of claim 1 wherein before bringing the stabilized blood clot and the most distal mesh element and the middle one of the mesh elements towards the most proximal of the three separate and distinct compressed and expandable mesh elements, a relative distance between the most distal mesh element and the middle one of the mesh elements is repeatedly altered to assist in positioning the stabilized blood clot against the most distal mesh element, and the most distal mesh element is rotated within the blood vessel to position a largest area of the opening which faces towards the interior catheter and the middle one of the three separate and distinct compressed and expandable mesh elements against the stabilized clot.

16. The method of claim 15 wherein the rotation of the most distal mesh element and securing of the stabilized clot between the most distal mesh element and the middle one of the three separate and distinct mesh elements is done under live visualization.

17. The method of claim 1 wherein both hard and soft clot are removed in an acute ischemic stroke patient, deep vein thrombosis patient or pulmonary embolism patient in a single pass without damaging the intima of an occluded blood vessel.

18. The method of claim 1 wherein at least one of a shear-wave dispersion ultrasound and an ultrasonic sensor configured to determine thrombus composition is used to measure ultrasound transducer properties of soft and hard clots before inserting the delivery catheter into the region within the blood vessel without passing the position of the blood.

19. The method of claim 18 wherein an artificial intelligence stored in memory and machine learning components configured to evaluate composition of retrieved soft and hard blood clots uses data derived from the at least one of a shear-wave dispersion ultrasound and an ultrasonic sensor to determine composition of to be retrieved soft and hard blood clots.

20. The method of claim wherein 19 the mechanical thrombectomy catheter combined with an aspiration device controlled by artificial intelligence and machine learning.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0078] This invention may be more completely understood with respect to the following description of various embodiments. While the disclosure is amenable to various modifications and alternative forms, specifics have been shown by way of example in the drawings and will be described in detail.

[0079] FIGS. 1A-G show serial views of the intravascular thrombectomy catheter during isolating, capturing, and removing blood clots from a blood vessel.

[0080] FIG. 1A shows a schematic view of the catheter device for retracting intravascular thrombotic material.

[0081] FIG. 1B shows the intravascular thrombectomy catheter device with its distal tip extending beyond the distal edge of the thrombus.

[0082] FIG. 1C shows the thrombectomy catheter device collapsed inside the retraction catheter with the guidewire removed.

[0083] FIG. 1D shows the thrombectomy device with catheter components deployed.

[0084] FIG. 1E shows the retraction catheter being pulled with the thrombectomy device over the thrombus.

[0085] FIG. 1F shows the collecting basket being positioned to collect the thrombus.

[0086] FIG. 1G shows the collecting basket deployed over the thrombus.

[0087] FIG. 1H is a cross-sectional illustration of a multi-lumen catheter with an inserted optical fiber that can be used to measure an optical signal in a thrombus in an artery.

[0088] FIG. 1I is a schematic of the brain of a patient illustrating a thrombus retraction procedure in which fluoroscopic images may be acquired and stored in memory by an MRI-based tracking system.

[0089] FIG. 2 is a schematic view of the thrombectomy catheter device showing the arrangement of the struts and the ring segments in relation to a thrombus.

[0090] FIG. 3 is a schematic view of the distal embolic protection component of the thrombectomy device.

[0091] FIG. 4 is a schematic of a tracking system to evaluate clot treatment in individual patients.

[0092] FIG. 5 is a schematic view of the major veins in the upper leg, pelvis, and thorax involved in DVT and PE.

[0093] FIG. 5B shows the use of image guidance to guide the thrombectomy device through the vasculature.

[0094] FIG. 6 is a schematic view of a custom-made handle to advance of the DVT / PE thrombectomy device.

[0095] FIG. 7 show the components of an aspiration device that can be added to the manifold attached to the hub of the guiding catheter or the collecting catheter.

[0096] FIG. 8 shows a mesh wire web having different protruding elements, protrusions, dots, or gripping elements that are on the wire, generally facing inward (towards where a clot or the thrombus would be in contact with the wire).

[0097] FIG. 8A shows a partially extended, unexpanded distal mesh from the delivery catheter.

[0098] FIG. 8B shows a fully extended, expanded distal mesh and expander mesh and three struts extending from the delivery catheter.

[0099] FIG. 9 shows a side view of a shaped distal mesh element capturing a clot.

[0100] FIG. 9A and FIG. 9B

[0101] FIG. 10 shows a fully deployed capture system.

[0102] FIG. 11 shows three different aspects or perspectives of the deployed ring-shaped structure’s four segments.

[0103] FIG. 12 shows a different perspective of the deployed ring-shaped structure segments of FIG. 11.

[0104] FIG. 13 shows a pre-deployed 13A catheter delivery system and deployed 13B catheter delivery assembly comprising a catheter, single retraction guidewire, and multiple dual wire element distal retraction guidewires.

[0105] FIG. 14A shows a pre-deployed advanced catheter delivery system with three deployable, expandable elements with at least three struts within the deploying catheter which are also carried, along with deployable, expandable elements.

[0106] FIG. 14B shows a partially deployed advanced catheter delivery system with three deployed, expandable elements.

[0107] FIG. 14C shows a fully deployed advanced catheter delivery system with three deployed, expandable elements still not expanded.

[0108] FIG. 14D shows a fully deployed advanced catheter delivery system with three deployed, expandable elements.

[0109] FIG. 15 shows the distal mesh element and the intermediate mesh element with a clot therebetween. The intermediate mesh element has an additional expandable element that can impact the clot within the expanded distal mesh element.

[0110] FIG. 15A shows an axial view of a blood vessel with a clot attached more against a single wall.

[0111] FIG. 15B shows a perspective view of the blood vessel and clot of 15A with the deployment device inserted and positioned past the clot, but no expandable elements deployed.

DETAILED DESCRIPTION OF THE INVENTION

[0112] This disclosure provides design, material, manufacturing method, and use alternatives for medical devices and systems. The device for removal of intravascular thrombus removal comprises accessing a venous blood vessel of a patient in which a retraction catheter is inserted to a site of clot. An aspiration catheter with wall-mounted suction may be attached to remove a vascular obstruction with one pass. Aspiration may be applied to the guiding or collecting catheters to decrease embolization of clot fragments.

[0113] An intravascular thrombus retraction device includes: wires that are compressible into a compact cylindrical form within a catheter and are self-expandable into a wire mesh web with at least some parallel wires forming openings in the wire mesh sufficient to allow fluid passage and small enough to filter particles of at least 0.001 mm, a base of the wire mesh web connected to radial ring-shaped structure supporting and maintaining an opening in the base of the wire mesh and forming a thrombus capture volume, and the radial ring-shaped structure being compressible into the catheter and being self-expandable when free of compressive forces within the catheter to open up into an open, expanded, radial ring-shaped structure which maintains the opening in the opening in the base of the wire mesh. There are also multiple intermediate guide wires connected to and spaced about the ring-shaped structure, the multiple intermediate guide wires are connected to withdrawal guidewires extending into the catheter. It is preferred that at least some of the wires in the wire mesh have protrusions extending inwardly into the thrombus capture volume, at least some of the protrusions having a height less than a distance between the at least some parallel wires.

[0114] An alternative intravascular thrombus retraction device includes: wires that are compressible into a compact cylindrical form within a catheter and are self-expandable into a wire mesh web with at least some parallel or helical wires forming mesh openings in the wire mesh sufficient to allow aqueous fluid passage and small enough to filter particles of at least 0.001 mm or thrombus particles having a size which is recognized as having potentially harmful effects in at least the smaller blood vessels in the brain. A base of the wire mesh web is connected to radial ring-shaped structure supporting and maintaining an opening in the base of the wire mesh and forming a thrombus capture volume within the wire mesh. The radial ring-shaped structure could in theory be a single continuous element having an elastic memory that is the radial ring shape, but for purposes of construction of the device, a radial ring element having more than two bend or flex points, of having pivots, rotating connections, or segmented elements that allow for easier and more shapely compression may be used. The radial ring-shaped structure is as described compressible into a thin roughly cylindrical shape within the catheter and is self-expandable when free of compressive forces within the catheter to open up into an open, expanded, radial ring-shaped structure which maintains the opening in the opening in the base of the wire mesh. There are also multiple intermediate guide wires connected to and spaced about the ring-shaped structure, the multiple intermediate guide wires are connected to withdrawal guidewires extending into the catheter. It is preferred that at least some of the wires in the wire mesh have protrusions extending inwardly into the thrombus capture volume, at least some of the protrusions having a height less than a distance between the at least some parallel wires.

[0115] The wire may be a non-thrombogenic metal and the protrusions have a height of less than 0.001 mm. Because of the relatively short time duration of the device within a blood stream, there may be a tolerable range of materials that can be used if they are non-thrombogenic within the time frame of the surgery. The protrusions may be elements, bumps, rods, and the like extending from surfaces of the wires and the protrusions may have concave, convex, flat, curvilinear, or pointed tips.

[0116] The device may include two catheters, a first catheter containing the wire mesh and ring-shaped structure in a compressed, non-expanded state, and a second catheter containing a compressed and expandable collection receptacle, the collection receptacle positioned within the second catheter such that upon release from the catheter, the collection receptacle expands to provide an opening in an opposed position with respect to the opening in the base of the wire mesh of a released and expanded wire mesh and ring-shaped structure.

[0117] The current technology further includes a method using a unique thrombus retraction device. The invention may include removing a blood clot from a position within a blood vessel with a process of at least: [0118] inserting a delivery catheter into a region within a blood vessel without passing the position of the blood clot, the delivery catheter comprising an exterior catheter, and a deployment catheter within a lumen of the delivery catheter; [0119] the deployment catheter includes: [0120] a) an interior catheter with a second lumen, and within the second lumen in linear orientation within the second lumen are three separate and distinct compressed and expandable mesh elements connected by at least two struts passing along a surface of a middle one of the compressed and expandable mesh elements; [0121] b) the at least two struts having elastic memory sufficient to expand themselves and provide expansion forces on the three separate and distinct compressed and expandable mesh elements; [0122] c) a most distal one of the three separate and distinct compressed and expandable mesh elements having an opening which faces towards the deployment catheter and the middle one of the three separate and distinct compressed and expandable mesh elements after the most distal one of the compressed and expandable mesh elements is deployed and expands; [0123] d) a most proximal one of the three separate and distinct compressed and expandable mesh elements having an opening which faces away from the deployment catheter and towards the middle one of the three separate and distinct compressed and expandable mesh elements after the most proximal one of the compressed and expandable mesh elements is deployed and expands; [0124] the method may further include extending the deployment catheter past the clot while the exterior catheter does not pass the position of the blood clot; [0125] once a leading end of the deployment catheter has passed the position of the blood clot, deploying only the most distal one of the three separate and distinct compressed and expandable mesh elements past the position of the blood clot, while the middle one of and the most proximal one of the three separate and distinct compressed and expandable mesh elements remain between the clot and the interior catheter; [0126] the at least two struts expanding to expand all of the three separate and distinct compressed and expandable mesh elements; [0127] withdrawing the most distal one of the three separate and distinct compressed and expandable mesh elements towards the blood clot and supporting it on or within the opening which faces towards the deployment catheter and the middle one of the three separate and distinct compressed and expandable mesh elements, and bringing the most distal mesh element and the middle one of the mesh elements together, with the blood clot stabilized between the most distal mesh element and the middle mesh element; [0128] bringing the stabilized blood clot and the most distal mesh element and the middle one of the mesh elements towards the most proximal of the three separate and distinct compressed and expandable mesh elements; [0129] at least partially withdrawing the deployment catheter into the delivery catheter; and [0130] withdrawing the delivery catheter from the blood vessel along with the blood clot.

[0131] The method may further include bringing the stabilized blood clot and the most distal mesh element and the middle one of the mesh elements towards the most proximal of the three separate and distinct compressed and expandable mesh elements; [0132] at least partially withdrawing the deployment catheter into the delivery catheter; and [0133] withdrawing the delivery catheter from the blood vessel along with the blood clot are performed sequentially.

[0134] The method may further include bringing the stabilized blood clot and the most distal mesh element and the middle one of the mesh elements towards the most proximal of the three separate and distinct compressed and expandable mesh elements; [0135] at least partially withdrawing the deployment catheter into the delivery catheter; and [0136] withdrawing the delivery catheter from the blood vessel along with the blood clot are performed contemporaneously.

[0137] The method may have a surface of the middle mesh element conformed against a surface of the most distal mesh element, and particularly against the opening in the most distal mesh element.

[0138] The method may be practiced wherein there are at least three struts with elastic memory deployed from the deployment catheter. The elastic memory bows the struts outwardly, away from a central axis of the inner catheter of the deployment catheter and exerting expanding forces on at least some, if not all of the three separate and distinct compressed and expandable mesh elements, and always the middle of the three mesh elements.

[0139] The method may be practiced wherein the opening in the most distal one of the mesh elements forms a surface that is not orthogonal to surfaces within the blood vessel. The opening may be orthogonal to both opposed surfaces of a blood vessel, but may also be angled between 5 degrees to 90 degrees (measured by a closest point or contact point and referred to herein as the “contact point,” even if not in contact, between one edge of the opening and one of the opposed surfaces. Preferably this angle (as measured from a range including the most obtuse angles between the contact point (e.g., 922) and an opposed portion of the opening 924). The opening may also be curved, so that when the opening is viewed from a side view, element 920 in FIG. 14D may be straight, concave or convex. The angling at contact point 922, which may be forward leaning or rearward leaning, provides two apparent improvement functions in the practice of the method. It may act to assure a faster and more complete expansion of the distal compressed mesh element 906 and it may act to assist in scooping in thrombi or emboli adjacent surfaces of the blood vessel.

[0140] The device may have the ring-shaped structure include or be attached to struts which place expanding or restraining force on the ring-shaped structure to maintain the opening in an expanded and open position.

[0141] The device may also or alternatively have the collection receptacle include or be attached to struts which place expanding or restraining force on the opening in the opposed position to maintain the opening in the opposed position in an expanded and open position.

[0142] A method of capturing a thrombus within vasculature may include: comprising providing the above described intravascular thrombus retraction device, which may alternatively be characterized as wires that are compressible into a compact cylindrical form within a catheter and are self-expandable into a wire mesh web with at least some parallel wires forming openings in the wire mesh sufficient to allow fluid passage and small enough to filter particles of at least 0.001 mm, a base of the wire mesh web connected to radially ring-shaped structure supporting and maintaining an opening in the base of the wire mesh and forming a thrombus capture volume, the ring-shaped structure being compressible into the catheter and being self-expandable when free of compressive forces within the catheter to open up into the open, expanded ring-shaped structure, maintaining the opening in the opening in the base of the wire mesh, multiple intermediate guide wires are connected to and spaced about the ring-shaped structure, the multiple intermediate guide wires are connected to withdrawal guidewires extending into the catheter, at least some of the wires in the wire mesh having protrusions extending inwardly into the thrombus capture volume, at least some of the protrusions having a height less than a distance between the at least some parallel wires; the method comprising: [0143] a) inserting the device into a blood vessel having a thrombus; [0144] b) advancing a distal end of the catheter of the device towards a thrombus; [0145] c) deploying the compressed wire mesh and ring-shaped structure distally past the thrombus; [0146] d) expanding the wire mesh and ring-shaped structure past the thrombus; [0147] e) retracting the wire mesh and ring-shaped structure by applying tension to the withdrawal guidewires in a first retraction step; and [0148] f) capturing the thrombus within the wire mesh during the first retraction step.

[0149] The wire may be composed of a non-thrombogenic metal and the protrusions have a height of less than 0.001 mm, and during the first retraction step, the protrusions engage and grasp a surface of the thrombus.

[0150] The present disclosure further relates to a method of treating DVT and PE in the peripheral vasculature of a patient. The method includes providing a thrombectomy device that can be tubular and is formed of a braided filament mesh structure. The mesh structure can have a proximal end of the attached to a distal end. The invention includes advancing a catheter with the thrombectomy device through a vascular thrombus in a venous vessel. A shaft extends through the catheter and a distal end is coupled to a proximal end. The method includes deploying the thrombectomy device from the catheter from a constrained configuration to an expanded configuration. In some embodiments, the thrombectomy device engages at least a wall of the venous vessel distally past the thrombus at full expansion. The method includes retracting the thrombectomy device proximally to separate a portion of the thrombus from the venous vessel wall while the mesh structure captures the thrombus. The method includes withdrawing the thrombectomy device from the patient to remove the thrombus from the venous vessel.

[0151] Advancing the thrombectomy device includes inserting the catheter into the venous vessel until a radiopaque distal tip of the catheter is distally past the thrombus. In some embodiments, deploying the thrombectomy device from the constrained configuration to the expanded configuration includes advancing the shaft distally until the thrombectomy device is beyond a distal end of the catheter. Deploying the thrombectomy device further includes determining a position of the thrombectomy device with respect to the catheter via imaging of a first radiopaque marker located on the catheter and a second radiopaque marker located on at least one of the shaft or mesh structure.

[0152] The vascular thrombectomy device is added into the mesh structure by entering the expandable tubular portion via at least an aperture located at the proximal end of the self-expanding stent. The method includes inserting the catheter into the venous vessel through an access site, which is a popliteal venous site, a femoral venous site, or an internal jugular venous site. The venous vessel has a diameter of at least 5 millimeters and may include a femoral vein, an iliac vein, a popliteal vein, a posterior tibial vein, an anterior tibial vein, or a peroneal vein.

[0153] The method further includes: percutaneously accessing the venous vessel of the patient with an introducer sheath through an access site into the venous vessel of the patient, advancing a distal end of the introducer sheath to a position proximal of the thrombus, and inserting the catheter through a lumen of the introducer sheath so that a distal tip of the catheter is distally past the thrombus.

[0154] Withdrawing the thrombectomy device from the patient includes: retracting the thrombus extraction device relative to the introducer sheath until an opening is within the self-expanding stent, collapsing the stent portion and mesh structure so as to compress the thrombus, retracting the stent portion and mesh structure into the introducer sheath, and removing the thrombectomy device from the introducer sheath.

[0155] The method may further include extruding at least some of the thrombus through the distal portion of the expandable tubular portion and capturing a part of the thrombus in the self-expanding funnel or further compressing the thrombus through a mesh of the self-expanding funnel. The method may further includes aspirating the thrombus through an aspiration port connected to a proximal end of the introducer sheath.

[0156] One aspect of the present disclosure relates to a method of treating DVT in a peripheral vasculature of a patient to include percutaneously accessing a venous vessel of a patient with an introducer sheath through a popliteal vein site; and inserting a catheter with a thrombectomy device through a lumen of the introducer sheath so that the catheter is distally past the thrombus.

[0157] In some embodiments of the invention, a proximal end of the mesh structure may be attached to a distal end of the fenestrated structure. The thrombectomy device may be deployed from a constrained configuration to an expanded configuration by advancing a shaft distally until the stent portion of the thrombectomy device is beyond the distal end of the catheter.

[0158] One aspect of the present invention relates to a removal of thrombus from an artery or a vein of a patient by providing a thrombectomy device with a net-like filament mesh structure; advancing with the thrombectomy device through a thrombus, and deploying the thrombectomy device to engage a wall of the blood vessel. Retracting the thrombectomy device to separate a portion of the thrombus from the vessel wall and to capture the portion of the thrombus within the net-like mesh structure to remove thrombus from the patient.

[0159] In the method of the invention, fluoroscopically monitoring deployment of the thrombectomy device beyond first radiopaque marker located on the catheter relative to a second radiopaque marker located on the thrombectomy device. In some embodiments, the thrombus is located in the peripheral vasculature of the patient and the blood vessel has a diameter of at least 5 millimeters and includes at least one of the following: a femoral vein, an iliac vein, a popliteal vein, a posterior tibial vein, an anterior tibial vein, or a peroneal vein. In some embodiments of the invention, the method includes aspirating or infusing a thrombolytic agent into or from the blood vessel before, during, or after thrombus extraction.

[0160] FIGS. 1A-G depict steps for the mechanical thrombectomy device in a blood vessel 100 with a thrombus 110. A guiding catheter 120 can be positioned by transluminal catheter delivery within the lumen of the blood vessel 100 proximal to the thrombus using image-guided techniques. A retraction catheter 130 can pass through the guiding catheter 120 and may be positioned just below the proximal aspect of clot 110. As shown in FIG. 1A, a guidewire 140 can be placed proximal or distal to the thrombus 110 to be used to guide the collecting or retraction catheter 130. The retraction catheter 130 can then pass through guiding catheter 120 and over guidewire 140 to a position with its distal tip placed distal to the distal edge of the thrombus 110 as shown in FIG. 1B. The thrombectomy device with retracting wire 140, struts 170, ring structure 180 and web 190 can be passed through the retraction catheter or may be pre-loaded inside the retraction catheter 130. As shown in FIG. 1C, the guidewire 160 can be removed. The thrombectomy device can be deployed by manipulating the retraction wire 160 as shown in FIG. 1D. As shown in FIG. 1E, the retraction catheter 150 can be positioned proximally with the thrombectomy device pulled down over thrombus 110 in FIG. 1A. As shown in FIG. 1F, the collecting basket 135 may be deployed from the collecting catheter 130 to collect the thrombus as shown in FIG. 1G.

[0161] When possible, the entire thrombus 110 may be pulled into the guiding catheter 120 and removed from the body, leaving the guiding catheter 120 in place. If the clot is too large to be pulled into and through the guiding catheter 120, aspiration may be applied to the guiding catheter or the collecting catheter 130, wherein a catheter connected to an aspiration system can be hooked to the flushing system for the guiding catheter via a 3-way stopcock. Aspiration can be usefully added when applied to the clot that has been pulled into the collecting catheter 130 to make it smaller for removal through the guiding catheter 120.

[0162] FIG. 2 is a schematic view of the thrombectomy device showing the arrangement of the struts 172, 174, 176, 178 and the ring segment 182. The device uses a web structure with retraction wires to retract thrombus 190. The device includes expandable struts having a closed compact configuration 184 and an open expanded configuration 186. In an optional embodiment, additional collection features such as cactus-claws, end-hooks and hook-type imaging may be included. In some embodiments, these features can be formed from various metals or alloys such as Nitinol, platinum, cobalt-chrome alloys, 35N LT, Elgiloy™, stainless steel, tungsten, or titanium.

[0163] In one embodiment of the disclosure shown in FIG. 3, fluoroscopically visible markers 188 are applied to the retraction ring, the retraction wire, and the collecting basket 180 and to the tip of the guiding catheter 150 to facilitate localization of all components. Some examples of radiopaque materials include gold, platinum, palladium, tantalum, tungsten alloy, and polymer material loaded with a radiopaque filler. The thrombectomy device may also be made from a metal, metal alloy, polymer, a metal-polymer composite, ceramics, or other suitable material including, such as304V, 304L, and 316LV stainless steel; mild steel; nickel-titanium alloy such as linear-elastic and/or super-elastic nitinol; and nickel-chromium-molybdenum alloys.

[0164] In another embodiment, the device can be equipped with imaging sensors 350, or with sensors measuring physiological parameters 360 such as pressure, temperature, and oximetry. In one embodiment, FOSS technology facilitates the visualization of thrombectomy catheters 330 and wires 340 without the need for fluoroscopy. In addition to reducing the need for X-ray exposure of the patient and medical personnel, the FOSS technology also enables more detailed views of device positioning. In an exemplary embodiment, optical fibers are embedded in the device and equipped with Fiber Bragg Gratings, which enables the determination in 3 dimensions of the shape and position of the catheters and wires in real-time and with high accuracy. The shape and position of the catheters and wires can then be superimposed on roadmap views of the vasculature and pathology.

[0165] As shown in FIG. 4, sensors 461 may be connected to a host computer 460, wherein diagnostic algorithms 480 can be used to evaluate treatment plans for individual patients 462 and to actively modify existing treatment plans by physicians 442. by the host computer 460. Observation of imaging changes 499 can be clinically A computer-based 491 tracking system 400 can be used in patient studies to investigate clot composition with respect to the age 450, composition 460 and size of a thrombus 470. During formation of a thrombus, characteristic alterations in fluorescence contrast imaging 410 and thrombus imaging 430 may be registered useful in evaluating the potential utility of various alternative therapeutic interventions, such as, for example, drug thrombolytic therapy 440 and mechanical thrombectomy 441. Imaging 410, 430 may be used to guide the thrombectomy device through the vasculature 520 through under manual control of a host computer 460. Since branching of the main pulmonary arteries may be anatomically complex, it may be difficult to locate and catheterize an occluded vessel 500 when using single plane fluoroscopy 410.

[0166] As shown in FIG. 5, image guidance can be used to guide the thrombectomy device through the vasculature 500 toward the correct location 530, 540, to manipulate various functions of the device 510, and to manage the retraction of the thrombus (not shown) PE is considered to be part of the same continuum of disease as DVT with over 95% of emboli originating in the legs. Mechanical clot removal, as disclosed in the present disclosure, is relatively rapid compared to the use of thrombolytics. Pulmonary emboli, particularly those in the proximal aspects of the pulmonary arteries, can be quite large requiring a larger retriever catheter and wires than for most DVT cases. Biplane fluoroscopic systems such as those used for cerebral angiography and intervention can be used to improve the catheterization process.

[0167] The handle 600 (FIG. 6) may have a proximal end portion and a distal end portion. The distal end portion of the handle which may be connected or attached to the proximal shaft. In some embodiments, an adaptor may facilitate a connection between the handle and the proximal shaft. The handle may be formed from a polymer material, a metal material, a combination of metal material and a polymer material, and/or one or other suitable materials. Further, the handle may be formed with a suitable forming technique including machining, molding, grinding, injection molding, and laser cutting.

[0168] In one embodiment shown in FIG. 6, the device has a custom-made handle 600, in which an operator can engage a thumb engaging surface of the device 610 to transmit movement to the device through a compressed coil spring 620, wherein the operator is able to apply a calibrated force 630 to the device. The calibrated forces may be spaced a predetermined linear distance, to include detents, cut-outs, recesses, spacings, notches, indents, bumps, protrusions and/or other features. As shown in FIG. 6, the calibration forces may be linearly drawn as it is moved one or more predetermined distances in the longitudinal direction. In one example, the adjustment member may include a portion having a protrusion to include a cut-out, recess, spacing, notch, indent, and/or other formations to facilitate engaging the restrictions in or on the handle.

[0169] As shown in FIG. 7, a catheter 710 connected to an aspiration device 720 can be added to the manifold attached to the hub of the guiding catheter 730 or the collecting catheter 735 so that aspiration can be applied to the entire system to facilitate thrombus retraction, and prevent fragmentation and embolization of fragments through the guiding catheter 730. Aspiration coupled with mechanical thrombectomy 740 can thereby assist in the retraction of large clots. An aspirational system attached to the manifold of the guiding catheter may help reduce the size of the clot within the collecting device 735 to facilitate removal of the thrombus. Aspiration can also reduce the potential for distal embolization as the clot is manipulated.

[0170] The entire thrombus may be pulled into the guiding catheter 120 and removed from the body, leaving the guiding catheter 120 in place. If the clot 110 is too large to be pulled into and through the guiding catheter 120, aspiration may be applied to the guiding catheter or the collecting catheter 130 , wherein a catheter connected to an aspiration system can be hooked to the flushing system for the guiding catheter via a 3-way stopcock 750. Aspiration 760 can thus be usefully added when applied to the clot that has been pulled into the collecting device 4 to make it smaller for removal through the guiding catheter 120.

[0171] A method of treating deep vein thrombosis and pulmonary embolisms may include accessing a venous vessel of a patient, wherein a retraction catheter containing a clot treatment device is inserted into the venous circulatory system to a site of clot, wherein an aspiration catheter in inserted with wall-mounted suction attached to its inflow port, wherein the aspiration component can remove clot and other debris, and, wherein complete removal of both soft and hard components of a vascular obstruction is completed with one pass within in ninety percent of cases.

[0172] A device that may be used in the method may include a device equipped with a collecting mechanism in the form of a collecting catheter that passes over the retraction catheter, and that is equipped with a collecting structure that can be deployed when moving the collecting catheter beyond the end of the guiding catheter, surrounding the object when the object is extracted using the retraction catheter.

[0173] The method may further include accessing a venous vessel, inserting into retraction catheter into vessel, and restoring blood flow using the clot retraction device.

[0174] An alternative multi-lumen, multi-functional catheter system may include a plurality of axial lumens, wherein at least one physiological measuring device is present within a clot retraction catheter, wherein said physiological measuring device is connected to a host computer which is equipped for receiving information regarding DVT and PE treatment plans, wherein the host computer contains a treatment planning and therapy algorithm for individual DVT and PE patients, and, wherein the host computer signals the operator to actively modify the existing treatment plan as the therapy algorithm progresses.

[0175] A thrombectomy catheter comprising: an elongate flexible catheter body having a proximal end, a distal end and a central lumen extending longitudinally through the catheter body, wherein the catheter comprises a catheter with a variable durometer outer jacket, wherein the catheter wall thickness ratio of the inner diameter to the outer diameter is 0.80 or higher, wherein the tensile strength of the catheter is higher than 2 lbs.

[0176] Another device for removing blood clots may include an intravascular catheter having a distal end and a proximal end, the catheter having an inner lumen and an outer lumen, wherein an aspiration pump is attached to the proximal end of the catheter, and a mechanically actuated positive displacement powered by a rotating motor, wherein the motor rotates at a speed below 2000 RPM when driving the aspiration pump and wherein the speed of the motor is cycled at a frequency below 10 Hz.

[0177] Another method of treating deep vein thrombosis in a peripheral vasculature of a patient may include: percutaneously accessing a venous vessel of a patient with an introducer sheath through an access site into the venous vessel of the patient; inserting a catheter constraining a thrombectomy device through the lumen of the introducer sheath so that a distal tip of the catheter is distally past a portion of the thrombus ; deploying the thrombectomy device from a constrained configuration to an expanded configuration, wherein the thrombectomy device is in an expanded state between about 20 degrees and about 50 degrees; and, removing the thrombectomy device from the patient.

[0178] It will be apparent to those skilled in the art that various modifications and variations can be made in the disclosed systems and processes. It is intended that the specification and examples be considered as exemplary only.

[0179] Thrombus in the vasculature includes a range of morphologies and consistencies. Typically, older thrombus material contains a higher percentage of fibrin, making it less compressible with a harder outer surface that makes it more difficult to ensnare or aspirate than more acute thrombus which is softer. Current mechanical thrombectomy devices may not penetrate the surface of a hard fibrin-rich thrombus or produce sufficient force to grip the thrombus. It can be very difficult to aspirate a hard thrombus without first breaking it into pieces, which could then embolize into distal branches. During thrombectomy, 75-85% of thrombi can be removed using current devices, such as stent-retrievers and aspirators. However, the remaining 15-25% of intravascular thrombus cannot be easily removed by mechanical devices because the thrombus is hard.

[0180] CT and fluoroscopy imaging cannot typically identify the composition of intravascular thrombus, which may vary from relatively hard to relatively gel-like and soft. An obstructing thrombus in a blood vessel of the brain can be a medical emergency caused by occlusion of blood vessels to the brain or within the brain. Although an ischemic event can occur anywhere in the vascular system, the carotid artery bifurcation and the origin of the internal carotid artery are the most frequent sites for thrombotic occlusions of cerebral blood vessels.

[0181] Methods for imaging thrombus are reviewed in the present disclosure. As used herein, an imaging technology may include, positron-emission tomography, single photon emission computed tomography, magnetic resonance imaging, optical imaging, ultrasound, photoacoustic imaging, computed tomography, or near-infrared fluorescence-imaging.

[0182] FIG. 1H is a cross-sectional view of a catheter 10 in an artery adjacent to intravascular thrombus 62. In an exemplary embodiment of the disclosure, an optical fiber 95 is used to measure an optical signal collected from the thrombus 62, which is then output to an MRI-based tracking system 95. The catheter 10 may be advanced to the thrombus 62 to illuminate the thrombus 62, wherein an optical measurement unit 70 enables identification of the optical signal 42 of the thrombus 62 which reflects the content of the thrombus 62. A detector in the MRI system 99 converts the optical signal 42 into an electrical analog signal, and an analog-to-digital conversion circuit 93 digitizes the signal to the MRI tracking system 95 for analysis.

[0183] In one embodiment of the disclosure shown in FIG. 11, a schematic of the brain of a patient illustrates a thrombus retraction procedure 100 in which fluoroscopic images 136, 150, 160 may be acquired and stored in memory in a host computer for subsequent retrieval by an MRI-based tracking system 140.

[0184] A method for visualizing thrombus in an artery includes a wavelength-specific reflector being advanced to traverse the thrombus, wherein the incident light is selectively reflected at the diagnostic wavelength after interacting with the thrombus, wherein passing the optical signal through the thrombus increases an optical attenuation signal compared with a single pass, wherein the host computer analyzes transmitted optical signals, and, wherein the host computer identifies whether the thrombus is hard or soft based on the wavelength signal.

[0185] In the method, an optical fiber is adapted to allow light to interact with the thrombus, wherein hard thrombus absorbs less light than thrombus, and, wherein the MRI system can establish the composition of the thrombus based on the optical attenuation of the thrombus.

[0186] A device for tracking thrombus in a patient’s vasculature may include a measuring device connected to a host computer that can evaluate thrombus retraction, wherein the device is equipped with both optical sensors and imaging sensors, wherein the host computer contains a therapy algorithm for individual patients, and wherein the host computer can actively modify thrombus retraction as the therapy algorithm progresses.

[0187] The above device may have the host computer determine the thrombus composition based its optical transmission, and the MRI can be used to evaluate whether thrombus composition reduces its susceptibility to recombinant tissue plasminogen activator. The host computer may determine retraction routes, speed, and status of thrombus for individual patients.

[0188] A method for tracking thrombus in the vasculature comprising analyzing the intensity of an optical signal from a sensor in a catheter positioned in a blood vessel of a patient may include using an optical signal from the sensor is attenuated by thrombus, wherein an MRI-based host computer tracks the thrombus by analyzing the measured signal attenuation, and, wherein the location of the thrombus is converted by the MRI-bases host computer into MRI coordinates using a registration transformation.

[0189] It should be understood that the foregoing description is merely illustrative of the present disclosure. Various alternatives and modifications can be devised by those skilled in the art without departing from the scope or spirit of the disclosure.

[0190] A further method of treating deep vein thrombosis in a peripheral vasculature of a patient, the method comprising: percutaneously accessing a venous vessel of a patient with an introducer sheath through an access site into the venous vessel of the patient; inserting a catheter constraining a thrombectomy device through the lumen of the introducer sheath so that a distal tip of the catheter is distally past a portion of the thrombus ; deploying the thrombectomy device from a constrained configuration to an expanded configuration, wherein the thrombectomy device is in an expanded state between about 20 degrees and about 50 degrees; and, removing the thrombectomy device from the patient.

[0191] FIG. 8 shows a mesh web wire system 800 having different protruding elements. protrusions, dots, or gripping elements (804, 806, 808, 810, 812, 814, 816 818) that are on the wire 802, generally facing inward (towards where a clot or a thrombus would be in contact with the wire 802. Different structures for these protruding elements are exemplified separately to show how the different shapes and dimensions and configurations can be selected to provide unique and designed functions with respect to different types of clots, thrombus and debris based on size, texture, rheology and dimensions of the unwanted materials to be captured. Protrusion 804 is a generic and simplest protrusion to form and likely the easiest to manufacture, comprising a truncated spherical dot.

[0192] Element 806 is a pyramidal element, with a more pointed tip to grasp thrombus with texture and hard surfaces. Element 808 has inwardly sloped side rising to a flat surface to grasp softer clots. Element 810 has inwardly sloped side rising to a concave surface 810a to grasp soft clots and with edges of the concave surface grasping into the clot, yet retaining a large surface area of contact with the particle to be removed.

[0193] Element 812 is again a relatively generic and simple protrusion to form. Element 814 is shown with outwardly sloped sides 814a which can be used to trap smaller particles as the wire mesh is withdrawn, the sloped sides capturing particles that might even escape the wire mesh. Element 816 is a truncated spherical element, with the cut through the sphere sufficiently low as to again create inwardly sloped surfaces 816a which may provide the small particle capture function described for element 814 above. Element 818 is shown with a textured surface 818a which can assist in grasping clots that might have smoother or more slippery surfaces.

[0194] A textured, grooved, irregular surface such as in 818a can be provided on any of the individual structures. Many techniques for forming such surfaces such as embossing, leaching of soluble materials (e.g., soluble polymers, salts, sugars, etc.) in the deposited metal, ceramic, composite or polymeric elements, and the like.

[0195] FIG. 9 shows a side view of a shaped distal mesh element 906a capturing a clot 914. Only two struts 904 are shown for convenience. The lower of the two struts shown as 904 is connected to the distal mesh element 906a just beyond a feature 932 on a bottom portion of the distal mesh element 906a. This feature 932 would likely slide along a wall of a blood vessel (not shown), with a curved leading section 936 to minutely elevate the leading section 936 so as to avoiding plowing into or scraping the blood vessel. The extreme front of this leading section 938 may revert backwards to form a lifting function on the thrombus 914. That extreme front of this leading section 938 may be flat or curved (preferably convex curve, but concave may provide an additional function).

[0196] FIG. 10 shows a fully deployed capture system (with the crosswires in the capture web 390 not shown to facilitate other distinguishing elements. The circular ring-shaped element is circular in an aspect view, but from this side view, the connection points for the distal guidewires 372, 374, 376, 378 to the segments of the ring-shaped structure 382, 384, 386, 388 are not within a single plane. The primary retraction guidewires 362, 364 are shown still within the deployment catheter 350.

[0197] FIG. 11 shows three different aspects or perspectives of the deployed ring-shaped structure’s four segments 482, 484, 486, 488 secured by four distal guidewires 472, 474, 476, 478 with a single primary guidewire 462 drawing or releasing the ring-shaped structure and progressively allowing the ring-shaped structure to deform or collapse as progressively shown in FIGS. 11A, 11B and 11C.

[0198] FIG. 12 shows a different perspective of the deployed ring-shaped structure segments 582, 584, 586, 588 with the connection points 583, 585, 587, 589 connecting the segments to the distal guidewires 572, 574, 576, 578 which are in turn connected to primary retraction guidewires 562, 564 within the catheter 550.

[0199] FIG. 13 (13A, 13B) shows a pre-deployed 13A and deployed 13B catheter delivery assembly comprising a catheter 650, single retraction guidewire 660, multiple dual wire element distal retraction guidewires 670, the dual wire element distal retraction guidewires 670 being attached to sides of struts 680 forming the ring-shaped circular opening supporting elements for the wire mesh web 690 (shown without cross wire hatching).

[0200] FIG. 14A shows a pre-deployed advanced catheter delivery system 900 with three deployable, expandable elements 906, 908 and 910. There are at least three struts 904 within the deploying catheter 902 which are also carried, along with deployable, expandable elements 906, 908 and 910 within the deployment catheter 900. Clot 914 is shown relative to the various stages of deployment and capture by the device.

[0201] FIG. 14B shows a partially deployed advanced catheter delivery system 900 with three deployed, expandable elements 906, 908 and 910.

[0202] FIG. 14C shows a fully deployed advanced catheter delivery system 900 with three deployed, expandable elements 906, 908 and 910 still not expanded.

[0203] FIG. 14D shows a fully deployed advanced catheter delivery system 900 with three deployed, expandable elements 906, 908 and 910 now expanded as forward (or distal) deployed retracting basket 906a, intermediate expander/containing-cover 908a (for sealing 906a), and the proximal retrieving basket 910. The at least three deployed and expanded struts 904a, 904b and 904c maintain and/or initiated/assisted the expansion of deployed, expanded elements 906a, 908a and 910a into the size and shape necessary to capture clot 914.

[0204] FIG. 15A shows an axial view 1500 of a blood vessel 1502 with a clot 1504 attached more against a single wall. There is a general open area 1506 within the blood vessel 1502, and a greatest distance 1508 between the clot 1504 and the wall 1502. In that area, noninvasive imaging and analytic techniques (not shown) should be used to determine an effective, preferred or best position for insertion of the delivery device 1510 in the greatest distance 1508 between the clot 1504 and the wall 1502. The operating technician or physician will put the delivery catheter in the most appropriate position, between the clots and the blood vessel wall, using the non-invasive visualization as mapping and directions, preferably under live visualization of the region.

[0205] FIG. 15B shows a perspective view 1500a of the blood vessel 1502 and clot 1504 of 15A with the deployment device 1510 inserted and positioned past the clot 1504, but no expandable elements (not shown) deployed. The deployment device beneath 1512 and beyond 1514 the clot 1504 is shown. It has passed through the greatest distance 1508 between the clot 1504 and the wall 1502. Additionally, a guide wire 1516 and an conductive wire 1518 are shown. The conductive wire 1518 may be used to operate elements or sub-devices (not shown) or release drugs or heat elements associated with the thrombectomy device of the present invention before or after deployment.

[0206] In the following figure and description of the operation of the expander, and additional function is available. The expander may be repeatedly expanded and deflated, forcing a surface of the expander against he clot to compress the clot and to assist in breaking up the clot within the captured environment of the forward collection mesh. The proximal side of the expander (closest to the delivery catheter) may be more rigid and less expandable once initially expanded. This can be effected by having a more dense, higher density mesh, or less flexible composition that the distal side of the expander. The face of the expander facing and engaging the clot may also be textured or have prongs or miniature blades thereon to assist in breaking up the clot.

[0207] The distal side of the expander undergoes macrostructural expansion and contraction, no merely thermal expansion which solids undergo. This can be done with motors, pumps, electrical rearrangement of structural elements, inflation-deflation of small balloons, and other known phenomena.

[0208] FIG. 15 shows the distal mesh element 1502 and the intermediate mesh element 1508 with a clot 1514 there between. The intermediate mesh element 1508 has an additional expandable element 1520 that when expanded in size to 1522 can impact the clot 1514 within the expanded distal mesh element 1502. The additional expandable element 1520 expands in a direct 1526 against the clot 1514.

[0209] FIG. 15 shows a thrombectomy net system 1500 with an expander 1508 that when expanded to 1522, acts to provide at least additional surface pressure which acts to break apart a thrombus 1514 that has been caught in between the distal mesh element collecting basket 1502 and the middle mesh element 1508 (referenced herein as the expander). The collecting basket 1502 and middle mesh expander element 1508 are initially expanded and then partially held open by struts with elastic memory 1504.

[0210] When the thrombus 1514 is contained within the holding basket 1502, a signal, such as an electrical signal (or radio frequency signal) is sent through an electrical wire 1524 to the expander 1508. Upon receiving this signaling, a responsive system in the expander 1508, the forward-facing face 1520 of the expander 1508 is extended with more force to provide at least pressure into the thrombus 1504 within the collecting basket 1502, assisting in breaking the thrombus 1514 apart, and allowing for its easier removal, as by retraction of the entire device and clot fragments into the delivery catheter, with or without aspiration of the area by additional device.

[0211] In an alternate embodiment, the expander 1508 has a further distinctly expandable element 1520, such as a quasi-balloon structure that expands (e.g., see 1522) upon receiving externally generated signals. The signals may be operated by a technician in the operating environment, as previously noted by electrical, RF or other signaling modality.

[0212] For example, the signals may be through wire 1524. In another alternate embodiment, the expander 1508 is a magnetic device that uses electromagnetic forces upon receiving power from wire 1524 that pushes the expanding section 1520 of the expander 1508 into/against the thrombus 1514. This not only secures the thrombus within the collecting basket 1502, but may also act in breaking the clot apart, and assisting in its removal.

[0213] As noted, the forward face of the expanding section 1522 (moving in direction 1526) may have protuberances, edges, thin blades, posts, etc. to penetrate into the thrombus, helping to break it into smaller pieces that may be able to be withdrawn into the lumen/cannula of the delivery catheter. There may even be a second signal causing these forward face additions to vibrate, further enhancing clot breakage. This may be done by a small vibrator (not shown) attached to the innards of expanding section 1522 or even within the expander 1508.

[0214] In addition to having expanding section 1520, 1522 as a balloon, with a pump or fluid access to expand it on demand, other technologies such as component rigidifying are known in the art.

[0215] U.S. Pat. No. 11,344,250 (Mou) describes an expandable electrophysiology catheters having electrodes mounted on splines of an expandable member. The splines of the expandable member include subsegments between a proximal location and a distal intersection at a central axis. The subsegments can include respective top-down profiles, and at least one of the top-down subsegment profiles is straight between the central axis and an adjacent top-down subsegment profile. The subsegments can be interconnected to extend continuously about the central axis from the proximal location to the distal intersection. Other embodiments are also described. This technology may be used to have expanding section 1612 expand on external demand.

[0216] Similarly, Piskarev et al. Wiley Online Library in “A Variable Stiffness Magnetic Catheter Made of a Conductive Phase-Change Polymer for Minimally Invasive Surgery,” first Published 06 Feb. 2022 at https://doi.org/10.1002/adfm.202107662, describes variable stiffness (vs) is an important feature that significantly enhances the dexterity of magnetic catheters used in minimally invasive surgeries, existing magnetic catheters with vs consist of sensors, heaters, and tubular structures filled with low melting point alloys, which have a large stiffness change ratio but are toxic to humans, in this paper, a vs magnetic catheter is described for minimally invasive surgery; the catheter is based on a novel variable stiffness thread (vst), which is made of a conductive shape memory polymer (csmp). the csmp is nontoxic and simultaneously serves as a heater, a temperature sensor, and a vs substrate, the vst is made through a new scalable fabrication process, which consists of a dipping technique that enables the fabrication of threads with the desired electrical resistance and thickness (with a step size of 70 .Math.m). selective bending of a multisegmented vst catheter with a diameter of 2.0 mm under an external magnetic field of 20 mt is demonstrated, compared to existing proof-of-concept vs catheters for cardiac ablation, each integrated vst segment has the lowest wall thickness of 0.75 mm and an outer diameter of 2.0 mm. the segment bends up to 51° and exhibits a stiffness change factor of 21. This also may be used for expanding section 1612 expand on external demand.

[0217] The method may be practiced wherein before bringing the stabilized blood clot and the most distal mesh element and the middle one of the mesh elements towards the most proximal of the three separate and distinct compressed and expandable mesh elements, a relative distance between the most distal mesh element and the middle one of the mesh elements is repeatedly altered to assist in positioning the stabilized blood clot against the most distal mesh element, and the most distal mesh element is rotated within the blood vessel to position a largest area of the opening which faces towards the interior catheter and the middle one of the three separate and distinct compressed and expandable mesh elements against the stabilized clot. As clots tends to have an asymmetric orientation within the blood vessel, the rotation of the opening of the most distal mesh element is intended to orient and place the forward edge of a sloped opening either against a surface of the clot either closest to the most distal mesh element or farthest from the most distal mesh element. Those orientations can be dependent upon the morphology and rheology of the clots in improving performance. This can be done under live visualization by the surgeon.

[0218] Similarly, ACS (American Chemical Society) Publications at https://doi.org/10.1021/acsami.1c06786 evidences another system which may be used for expanding section 1612 expand on external demand, in which Bhuyan et al. illustrate that the Jun. 8, 2021 publication of “Soft and Stretchable Liquid Metal Composites with Shape Memory and Healable Conductivity” in shape memory composites are fascinating materials with the ability to preserve deformed shapes that recover when triggered by certain external stimuli. Although elastomers are not inherently shape memory materials, the inclusion of phase-change materials within the elastomer can impart shape memory properties. When this filler changes the phase from liquid to solid, the effective modulus of the polymer increases significantly, enabling stiffness tuning. Using gallium, a metal with a low melting point (29.8° C.), it is possible to create elastomeric materials with metallic conductivity and shape memory properties. This concept has been used previously in core-shell (gallium-elastomer) fibers and foams, but here, we show that it can also be implemented in elastomeric films containing microchannels. Such microchannels are appealing because it is possible to control the geometry of the filler and create metallically conductive circuits. Stretching the solidified metal fractures the fillers; however, they can heal by body heat to restore conductivity. Such conductive, shape memory sheets with healable conductivity may find applications in stretchable electronics and soft robotics.

[0219] In determining treatments and tools to be used, although clot density is important, thrombus characteristics may only be a small part of the story, contingent on time since stroke onset, individual arterial anatomy, and presence of collaterals. We have previously suggested that stasis of thrombus in an intracranial vessel may rapidly produce a secondary thrombus around the original one that is RBC rich, particularly if there are poor collaterals or local angioarchitecture. Consistent with this, slow collateral flow can be associated with thrombus extension in large artery occlusions..sup.e95 This may explain the inability to identify a relationship between RBC composition and arteriogenic or cardioembolic stroke etiology, as the new thrombus components may constitute a significant portion of the overall thrombus, with the proportion of RBC in thrombus depending on timing from stroke onset.

[0220] The RBC-rich nature of a static, proximal, hyperacute thrombus is correlated with increased hyperdensity on NCCT and blooming artifact on MRI; longer clots may have more hyperdensity and blooming due to freshly formed clot extension within the intracranial vessel. However, we also know there is a time-dependent loss of density in occluded M1 segments within the first few hours. Therefore, depending on timing of patient presentation and imaging, thrombi may have very different composition and imaging characteristics. The lower stiffness and friction and increased permeability of the initial RBC component may facilitate higher penetration of thrombolytic agent and easier extraction. However, over time, more extensive fibrin deposition and crosslinking between RBC and fibrin may occur to facilitate stabilization of thrombus, as evidenced by RBC projections that allow interaction with each other and with fibrin fibers. Inhibitors of tPA may also play more of a role over time. All these factors may work to delay fibrinolysis and increase lytic resistance (a summary of dynamic changes in thrombus composition and imaging findings from time of stroke onset and visualization of these alterations on clot lysability).

[0221] The method of the claimed and disclosed invention bay be used in procedures where both hard and soft clot are removed in an acute ischemic stroke patient, deep vein thrombosis patient or pulmonary embolism patient in a single pass without damaging the intima of an occluded blood vessel. That method and other methods disclosed herein may have at least one of a shear-wave dispersion ultrasound and an ultrasonic sensor configured to determine thrombus composition is used to measure ultrasound transducer properties of soft and hard clots before inserting the delivery catheter into the region within the blood vessel without passing the position of the blood. Additionally, the method disclosed herein may have an an artificial intelligence function stored in memory and machine learning components configured to evaluate composition of retrieved soft and hard blood clots uses data derived from the at least one of a shear-wave dispersion ultrasound and an ultrasonic sensor to determine composition of to be retrieved soft and hard blood clots. In the use of the method of claim with the mechanical thrombectomy catheter, it may be combined with an aspiration device controlled by artificial intelligence and machine learning. The use of artificial intelligence and machine learning components can increase first-pass recanalization in a combined mechanical thrombectomy catheter aspiration device. The method may have artificial intelligence and machine learning to assist in visualizing thrombectomy catheters without fluoroscopy that can be superimposed on roadmap views of the vasculature and pathology before, during and after procedures. All of these methods may use sensors that can be connected to a host computer wherein diagnostic algorithms can be used to evaluate treatment plans for clot removal in individual patients. The artificial intelligence computer-based tracking system may be used in patients diagnosed with AIS, DVT or PE clots to monitor the age, composition, size and anatomical location of a thrombus, and/or to track blood clots in the body. For example, an artificial intelligence computer-based system may be used with biplane fluoroscopy to improve the accuracy of cerebral angiography and/or to track blood clots in AIS, DVT and PE patients. The artificial intelligence and a machine learning system may be used with a host computer to actively modify the clot treatment algorithm for individual AIS, DVT and PE patients during procedures in which the clots are removed.