Second layer ICAD device

Abstract

To provide a device for treating intravascular occlusions and stenotic lesions.SOLUTION: A design bringing together mechanical thrombectomy and stenting for more efficient treatment of occlusions and stenotic lesions in the cerebral vasculature features a dual-layer setup. The outer layer consists of an expandable stent cage with large cell openings which are capable of passing a thrombus into the inner expandable capture section layer. The clot capture section can be configured to grip and extract the occlusion. The outer cage is configured to be detached from the remainder of the device and left implanted as a stent to exert an outward radial force to support and / or dilate the region of stenosis. The device can have a distal fragment protection element to prevent the distal migration of elements liberated during the procedure.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates generally to devices and methods used to remove obstructions and treat stenosis in cerebral blood vessels during endovascular medical procedures, and more particularly to a device having removable elements that can be used as a standard clot retrieval device and can be left implanted within a stenotic lesion if desired. [Background technology]

[0002] Atherosclerosis results from lesions that narrow and reduce the space within the lumen of blood vessels in the vascular system. Such lesions are usually composed of plaque, which can be fat, cholesterol, calcium, or other components of blood. Severe blockages or occlusions can impede the flow of oxygenated blood to different organs and parts of the body, leading to other cardiovascular disorders such as heart attacks or strokes. The narrowing, or stenosis, of blood vessels can cause blood clots to solidify in situ and increases the risk that blood clots and other emboli can become lodged in such locations, especially in neurovasculature, where the diameter of the vessels is already small. Intracranial atherosclerotic disease (ICAD) is the narrowing of these arteries and vessels that supply blood to the brain and represents a common proximal mechanism of ischemic stroke.

[0003] Treatment of vascular occlusion is well known in the art. Methods may include utilizing drugs such as anticoagulants or antiplatelet agents, as well as medical procedures such as surgical endarterectomy, angioplasty, and stent placement. Much of the recent success in endovascular revascularization treatment (ERT) has been due to the further development of safe thrombectomy devices. Devices such as stentrievers, direct aspiration systems, and other clot retrieval devices are strongly associated with better clinical outcomes. However, these devices are primarily designed to recanalize the vessel by removing and retrieving the occluding emboli. If significant stenosis is present at the site of occlusion, sufficient recanalization may not occur, increasing the need for implanted stents.

[0004] Treatment methods for neurovascular in particular depend on multiple factors, including the degree of occlusion, the shape of the target occlusion site (i.e., trunk-like, branch-like, etc.), and the overall condition of the patient. For these reasons, it may be unclear whether the occlusion is the result of blood clotting alone, if stenosis is also present. During the treatment of stroke or transient ischemic attack, identifying stenotic lesions can be difficult because it is difficult to distinguish them from blood clots and other embolic-related occlusions through baseline angiography. This is especially true in the very small and tortuous vessels of the cerebral vasculature. In some cases, physicians may not be able to identify stenotic lesions until the procedure is underway. Therefore, physicians may need to have a variety of easily accessible treatment devices available, including stent systems, that can be dynamically adapted based on the diagnosis.

[0005] These difficulties add to the time of the procedure, and when both a clot and a stenosis are present, the physician is often required to exchange catheters, devices, and guidewires after removing the clot. The need to deliver multiple passes and devices during treatment can increase the likelihood of an ICAD lesion rupturing or releasing fragments, including, but not limited to, clots, plaque, and other thrombotic debris. The fragments can result in vascular obstruction causing widespread stroke or death. Summary of the Invention [Problem to be solved by the invention]

[0006] There is a constant need for shorter time to treatment to limit long-term damage in ischemic stroke patients. Because of the difficulty in diagnosing ICAD, physicians may need to cross the lesion multiple times during treatment, which may further increase the chance of rupture or fragmentation and lengthen the procedure. Thus, there remains a need for systems and devices with improved capabilities to address intravascular occlusions, particularly ICAD lesions in neurovascular vessels. [Means for solving the problem]

[0007] The objective of the present invention is to design to provide a system, device, and method that meets the above-mentioned needs. Having the ability to perform mechanical thrombectomy and stent placement procedures with a single device or system, such as the current design, can significantly reduce procedure time and therefore result in better clinical outcomes. This is especially true in stroke patients, where the extent of recovery is highly dependent on timing. Furthermore, for tricky cases where the obstruction is thrombotic or atherosclerotic and clot retrieval is unsuccessful, the current design significantly improves the flexibility of the procedure by maintaining a flow lumen through the clot and immediately deploying a stent after capture attempts to scaffold the lesion.

[0008] In general, the proposed system provides a dual capability set to address occlusions or obstructions in blood vessels. The occlusions can be one or more of clots, thrombus, lesions, or other emboli. The system can be deployed across the occlusions per standard stent or thrombus removal device in a single microcatheter. The outer layer consists of a stent cage with an open distal port and large cell openings that can pass the thrombus into the inner capture section layer. The cage can also act as a temporary stent, expanding the lesion wall with its radial force. The device can be retracted into the access catheter to retrieve the thrombus under aspiration or suction from the access catheter. Multiple retrieval passes can be performed until satisfactory recanalization occurs. Once the occlusion is cleared, the outer stent cage can be removed from the patient or repositioned at the target and separated as a permanent stent implant.

[0009] An exemplary device for clearing a detrimental obstruction from and stenting a patient's vessel may include an inner capture section and an outer stent cage deliverable from a microcatheter. The microcatheter may be navigated to a target site within a neurovasculature using standard interventional techniques and commercially available auxiliary devices such as access catheters, balloon guide catheters, and / or guidewires. The capture section of this device design may be used to retrieve an obstructive clot or thrombus and may have an elongate body having a proximal end, a distal end, a collapsed delivery configuration, and an expanded deployed configuration. The capture section may include a strut framework or truss that forms an outer network of closed cells. When the capture section is deployed from the collapsed delivery configuration, at least a portion of the strut framework may be configured to engage the clot in an expanded state. In another example, the device may transition from an expanded deployed configuration to a partially constrained clamping configuration, where one or more portions of the obstruction may be clamped between apexes of the strut framework of the capture section as the device is pulled back into the outer catheter. Suction applied during the procedure may help remove the clot from the blood vessel.

[0010] The stent cage of the device can also have a collapsed delivery configuration and a self-expanded deployed configuration, and can be expandable to a greater radial extent than the capture section when in the self-expanded deployed configuration. The cage can include a plurality of interconnected struts formed into a network of large peripheral cells. The cells are large enough so that there is little resistance to the movement of thrombus, clots, or other emboli into the receiving space inside the outer cage. The stent cage can also have one or more sections extending between its proximal and distal ends, where two or more struts of the plurality of struts are longitudinally aligned. In one example, the maximum radial dimension of the stent cage when expanded can be approximately equal to the maximum radial dimension of the expanded capture section. In one configuration, the struts of the stent cage and the struts of the capture section are longitudinally aligned such that thrombus can easily pass through the cage and capture section. In some examples, the stent cage can be more than twice the diameter of the capture section. When in the expanded deployed configuration, the stent cage may also be sized to have a maximum radial dimension greater than the maximum radial dimension of the target vessel such that the stent cage exerts an outward radial force on the vessel when deployed to increase the local size of the lumen. Such a configuration allows the outer cage to provide expansion and support of the vessel as a capture section, while also allowing any loose material to be collected and withdrawn from the patient.

[0011] The stent cage may be substantially tubular in shape and may be configured to be at least partially eccentric relative to the capturing section. In one configuration, the stent cage may have an open distal port with a flared peripheral edge. The flared edge may help the device to restrain and retain the deployed clot. At its proximal end, the stent cage may have a collar or breakaway point where the cage may be released from the remainder of the device and remain implanted as a stent when the capturing section is removed. The capturing section of the device and the stent cage may be delivered on a single actuable shaft. In an alternative example, the cage and capturing section may be longitudinally movable independently of one another and each may have their own proximal shaft for manipulating the cage and capturing section within the patient.

[0012] Mechanical thrombectomy procedures always carry the risk that fragments dislodged during the procedure may migrate distally and become additional emboli. Often, suction from one or more catheters is used to reverse the flow direction, but other protective measures may also be utilized. In one aspect of the current design, a fragment protective element may be attached to the device, anchored to and distal to the capturing portion, to act as a protective structure across the vessel lumen to occupy space and substantially block distal release of fragments. This element may be three-dimensional, having depth and a surface area greater than the cross-section of the capturing portion of the device. The protective element may have a proximal connecting member that allows it to float within the vessel distal to the remainder of the device or to float distal to the capturing portion inside the outer cage. The protective element may have a collapsed delivery state and may be deployed to expand to a greater radial extent than the expanded capturing section. The fragment filter at the distal end may take a number of porous forms, such as a mesh filter, a basket, a series of fibers or thin wires, or a series of struts arranged in a volumetric pattern.

[0013] In another example, a thrombus removal device capable of removing obstructions and treating stenotic lesions may include an outer cage and a retrieval device. The outer cage may be a substantially tubular structure having a maximum radial dimension approximately equal to or greater than the maximum radial size of the retrieval device. The outer cage may have a lattice of interconnected struts forming a network of closed cells. The network of cells may be of sufficiently low density such that thrombus or fragments are displaced and urged into the open interior receiving space of the cage. The outer cage may have a constrained delivery configuration when collapsed within the microcatheter. The cage may also be constructed from a shape memory alloy to have a predetermined expanded deployed configuration. When deployed, the outer cage may be configured to exert an outward radial force on a vessel having a lumen maximum radial size smaller than the maximum radial size of the outer cage. In one example, the maximum radial size of the outer cage may be about 6.0 mm in diameter.

[0014] The maximum radial size of the outer cage may also flare out to a larger radial diameter at the distal end to provide maximum openness and improve retrieval capabilities. The outer cage may also be configured to be detachable from the remainder of the device to remain implanted within the stenotic lesion. The implant scaffolds the lesion and maintains a flow lumen through the vessel.

[0015] The retrieval device may be at least partially disposed within the lumen of the outer cage. The retrieval device may have a proximal end, a distal end, and multiple struts that may converge at end connections to form adjacent segments along the length of the body. The retrieval device may have a constrained delivery configuration and an expanded deployed configuration. The struts of the adjacent segments may be configured to engage at least a portion of the vascular defect in the expanded deployed configuration and may embed, constrain, or clamp to provide a strong grip on the clot or thrombus for the initial step of disengaging from the vessel.

[0016] The treatment device may have a first proximal shaft for articulation of the retrieval device and a second proximal shaft on which the outer cage can be articulated. Being on separate shafts allows movement of the retrieval device and movement of the outer cage independent of each other and allows the retrieval device to be withdrawn by itself once a firm grip on the clot is obtained. Alternatively, a single shaft may be used where the retrieval device and outer cage are deployed and withdrawn together as a unit. Once the clot has been captured, the retrieval device may be withdrawn completely through the lumen of the outer catheter or may be withdrawn far enough to pack and clamp the firmer clot within the tip of the outer catheter or microcatheter.

[0017] Once the outer cage is separated and released, the proximal struts of the outer cage can expand from the point of separation so that the cage assumes a generally tubular shape to engage and appose the lesion and vessel wall, and the cage can remain within the vessel as an implanted stent.

[0018] In other cases, the device may further include a distal fragment protection element fixedly connected to the distal end of the retrieval device by a shaft or other connecting element. The protection element may protect against embolization and may be a distal net or scaffolding zone spanning the lumen space. Fibers or thin wires may be added to the scaffold without affecting the profile or deliverability of the device. Fragments captured by the protection element are withdrawn from the patient along with the retrieval device.

[0019] Also provided is a method of combining mechanical thrombectomy and stent placement procedures. The method may include some or all of the following steps, not necessarily in the order described. Access to the patient's vasculature may be obtained using conventionally known techniques. An access catheter with a hollow inner lumen and a microcatheter are guided to a target site in a cerebral blood vessel where an occlusive thrombus is lodged in a stenosed area. A self-expanding outer cage sized to exert a radial force on the wall of the target vessel when in an expanded, deployed state is delivered through the microcatheter. The outer cage may have a plurality of large cells surrounding an outer periphery and a separation point at its most proximal end. An expandable capturing portion is disposed on the outer cage, the capturing portion having a maximum radial size when expanded that is smaller than the maximum radial size of the outer cage. In an alternative example, the capturing portion may have a maximum radial size when expanded that is the same as or equivalent to the maximum radial size of the outer cage. In another alternative example, the capturing portion may have a maximum radial size when expanded that is slightly larger than the maximum radial dimension of the outer cage to constrain the capturing section when the outer cage is fully expanded. The fragment protection element may also be fixedly connected to the distal end of the capturing portion, or may be connected via a shaft or wire.

[0020] Suction may be applied through one or more catheters used in the procedure. A microcatheter may be advanced over a guidewire and standard techniques, the device introduced, and the outer cage and capture section deployed to expand within the vessel. Radiopaque markers, coatings, or other options known in the art may be used along the length of the device or at the proximal and distal ends of the outer cage to mark the end points of the device during the procedure. The cells around the outer cage are porous to displace and accommodate thrombus and lesion fragments into the interior of the cage. The capture section may be expanded to grasp and capture the thrombus. The outer cage and capture section with the captured thrombus may then be drawn into the access catheter using suction.

[0021] The outer cage and capturing section may be repeatedly advanced across the thrombus for further capture attempts as needed to clear the vessel. Once the thrombus is removed, the outer cage and capturing section may be redeployed to the stenotic region at the target site. The outer cage may then be separated to remain within the vessel as an embedded stent to protect the flow lumen and dilate the vessel.

[0022] Alternatively, the outer cage may be first released and implanted, followed by retraction of the capture section and captured thrombus into the access catheter and removal from the patient.

[0023] The method may also incorporate the step of positioning a distal fragment protection element near the distal end of the device. The fragment protection element may be fixedly connected to the distal end of the retrieval device by an anchored shaft or other connecting element. The protection element may remain in place during the procedure and during deployment of the stent cage as an implant to protect against embolization until removed along with the capture section.

[0024] Other aspects and features of the present disclosure will become apparent to those of ordinary skill in the art upon consideration of the following detailed description in conjunction with the accompanying figures. [Brief description of the drawings]

[0025] The above and further aspects of the present invention are further considered in conjunction with the following description of the accompanying drawings, in which like numerals in the various drawings indicate like structural elements and features. The drawings are not necessarily to scale, emphasis instead being placed on illustrating the principles of the present invention. The figures depict one or more implementations of the device of the present invention, by way of example only and not by way of limitation. It is expected that those skilled in the art may conceive and combine elements from multiple drawings to better suit the needs of the user. [Figure 1] 1 is an illustration of a dual purpose thrombectomy and stenting device according to an aspect of the present invention. [Diagram 2] FIG. 2 is a detailed diagram of the apparatus of FIG. 1 according to an embodiment of the present invention. [Diagram 3] 2 shows an outer cage of the device of FIG. 1 according to an embodiment of the present invention. [Figure 4] 2 shows an outer cage of the device of FIG. 1 implanted within a target vessel, according to an embodiment of the present invention. [Diagram 5] 2 shows a capture section and fragment protection element of the device of FIG. 1 according to an embodiment of the present invention. [Figure 6] FIG. 6 illustrates a front profile view of FIG. 5 according to an embodiment of the present invention. [Figure 7] FIG. 1 illustrates another dual purpose thrombectomy and stenting device in accordance with an aspect of the present invention. [Figure 8] 8 shows the device of FIG. 7 deployed in a blood vessel having an occlusive thrombus and a stenosed area, according to an embodiment of the invention. [Figure 9] FIG. 1 illustrates another dual purpose thrombectomy and stenting device in accordance with an aspect of the present invention. [Figure 10] 1 illustrates a further dual purpose thrombectomy and stenting device in accordance with an aspect of the present invention. [Figure 11a] 13A-13C show alternative configurations of fragment protection elements according to aspects of the present invention. [Figure 11b] 13A-13C show alternative configurations of fragment protection elements according to aspects of the present invention. [Figure 11c] 13A-13C show alternative configurations of fragment protection elements according to aspects of the present invention. [Figure 11d] 13A-13C show alternative configurations of fragment protection elements according to aspects of the present invention. [Figure 11e] 13A-13C show alternative configurations of fragment protection elements according to aspects of the present invention. [Figure 12a] 1 illustrates a flow process for using a device to perform a combined mechanical thrombectomy and stenting procedure, according to an embodiment of the present invention. [Figure 12b] 1 illustrates a flow process for using a device to perform a combined mechanical thrombectomy and stenting procedure, according to an embodiment of the present invention. [Figure 12c]1 illustrates a flow process for using a device to perform a combined mechanical thrombectomy and stenting procedure, according to an embodiment of the present invention. [Figure 12d] 1 illustrates a flow process for using a device to perform a combined mechanical thrombectomy and stenting procedure, according to an embodiment of the present invention. [Figure 13] 1 is a flow chart outlining a method for using the system to perform mechanical thrombectomy and stent placement procedures, according to an aspect of the present invention. [Figure 14] 1 is a flow chart outlining a method for using the system to perform mechanical thrombectomy and stent placement procedures, according to an aspect of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0026] Specific embodiments of the present invention will now be described in detail with reference to the drawings, in which like reference numbers indicate functionally similar or identical elements. It is an object of the present invention to provide a system or device that gives the physician the advantage of operational flexibility to accommodate complications or unknown conditions in endovascular procedures, such as when an occluded vessel has a blood clot and also has an underlying area of ​​stenosis that was not detected during angiography. These improvements can translate into safer and more rapid access to complex areas of intracranial arteries to remove occlusions and reduce procedure times.

[0027] Accessing various blood vessels in the vasculature, whether coronary, pulmonary, or cerebral, involves well-known procedural steps and the use of numerous conventional, commercially available accessory products. These products, such as angiographic materials, rotating hemostatic valves, and guidewires, are widely used in laboratories and medical procedures. When these products are used with the systems and methods of the present invention in the following description, their functions and exact configurations will not be described in detail. Although this specification is often related to the treatment of intracranial arteries, the systems and devices may be used in other body passageways as well.

[0028] Referring to the figures, FIG. 1 shows a device 100 that may include an inner capture section 110 having a collapsed delivery configuration and an expanded deployed configuration, and an outer stent cage 210 that at least partially overlaps the inner capture section 110. The outer stent cage 210 may also be radially expandable and may assume a maximum radial size that is less than, equal to, or greater than the maximum radial size of the capture section 110 when deployed. The device may have a proximal elongate shaft 64 that allows for manipulation by a user. The device may be delivered to a target site for a mechanical thrombectomy procedure using standard techniques using a guide sheath, access catheter, microcatheter, or other delivery system (not shown). The device may further include a fragment protection element 310 that may be deployed distal to the capture section to provide a physical barrier against debris that may be dislodged during the procedure.

[0029] Proximate the proximal end of the stent cage 210, a detachment point 214 may be provided on the device 100. The detachment point may be remotely actuated by a user to detach the stent cage from the remainder of the device. Any number of methods may be deployed for detachment such that the stent cage may be physically decoupled from the remainder of the system or device.

[0030] At least a portion(s) of the capture section 110 and stent cage 210 may be made from Nitinol or another shape memory material that has sufficient elastic strain capacity so that the elastic limit is not exceeded when the device 100 is in a collapsed delivery configuration within a delivery system. This strain capacity allows the device to be effectively "spring loaded" within a microcatheter or delivery catheter so that it can self-expand and engage the clot when deployed from the distal end of the delivery system.

[0031] Portions of device 100 may be made visible under fluoroscopy by adding alloying elements or by including radiopaque markers or coatings. For example, the device may have a distal radiopaque coil 67 and a proximal radiopaque coil 66 that is proximate the end of the capture section during a thrombectomy procedure.

[0032] 2 is a side view of the device of FIG. 1. At least a portion of the clot capture section 110 and filter element 314 may reside within the lumen of the stent cage 210. The capture section may be a stentriever and the longitudinal axis 228 of the capture section 110 may be aligned with or offset from the longitudinal axis of the stent cage 210. The distal end 218 of the stent cage may be open or may taper with a more conical profile. When open, there is no distal connection point between the stent cage 210 and the capture section 110. This may allow the capture section to move radially as it engages a clot.

[0033] The clot capture section 110, stent cage 210, and filter element 314 of the fragment protection element 310 can have a collapsed configuration for delivery and an expanded configuration for clot retrieval, flow restoration, and fragment protection. The elongate shaft 64 of the device can be a tapered wire shaft and can be constructed from stainless steel, MP35N, Nitinol, or other material with sufficiently high tensile strength and modulus to allow for responsive and consistent tracking of the device within the vessel.

[0034] The stent cage 210, the clot capture section 110, and the distal portion of the fragment filter element 314 together define a three-dimensional protective structure to substantially prevent clots or clot fragments from being released distally from the device. The fragment filter element 314 can take any of a number of forms and can have a structure with a surface that can be configured as a clot barrier surface. In one example, the fragment filter can have a spoke configuration made of a combination of struts 316. In other cases, the strut framework can be covered with a fiber mesh or fabric that can be permeable to liquids in the container but can impede the distal movement of larger solids. This protective structure prevents the release of clots or clot fragments that have entered the inner capture section 110 or the receiving space 220 between the inner clot capture section and the outer stent cage frame 210.

[0035] The example externally expandable stent cage 210 of FIG. 1 is shown in FIG. 3. The cage may have a distal end 218, a proximal end 216, and a proximal shaft 212 that allows for manipulation. In one example, the stent cage 210 may have a series of interconnected struts 229, 230, 231 that may define a substantially tubular structure centered on a longitudinal axis 228. Some struts 230 may terminate at a crown that has no distal connecting elements, while other struts 231 may terminate at a junction. The stent cage 210 may also have connecting arm struts 229 that define an outer surface that is mostly parallel to the longitudinal axis 228. The struts may form an outer circumferential network of closed cells through which the clot(s) may be displaced radially inward to enter the receiving space 220.

[0036] The distal end 218 of the stent cage 210 may be defined by a series of crowned or distal wavy struts 226. The wavy struts may flare with a large bend radius to atraumatically contact the vessel wall. The struts at the proximal end 216 of the stent cage may taper to a separation point 214 on the proximal shaft 212. The separation point may be configured to allow the stent cage to separate from the remainder of the device while still being implanted as a stent within the patient, such as within an ICAD lesion.

[0037] The separation point 214 of the stent cage 210 may have one or more collars, partial collars, or sleeves that may be assembled over a step mechanism in the shaft 212 to form a mechanical lock that may prevent disassembly of the joint during tension or compression. Alternatively, the collar may be assembled over a notch on the capture portion 110. The separation point may be actuated by mechanical, electrical, or other means to separate the stent cage, allowing the stent cage to anchor to the stenotic region. Once released from the separation point, the stent cage is held in place within the vessel by an outward radial force exerted on the vessel wall.

[0038] In another example, the stent cage may be a stent having a plurality of resilient metal strands formed in a braided or mesh pattern. The strands or struts of the stent may extend longitudinally and be woven in a generally helical configuration having as a common axis the central axis or centerline of the resulting tubular structure. A first set of strands may be wound in one direction while being axially displaced from one another. A second group of strands may be wound in the opposite direction to the first group while being axially displaced relative to one another.

[0039] It should be noted that, as used herein, while elements are described and visualized in the drawings as tubular structures and generally illustrated as substantially right cylindrical structures, the terms "tubular" and "tube" should be interpreted broadly and are not meant to be limited to right cylindrical structures, or structures that are strictly circular in cross section, or of uniform cross section along their length.

[0040] The stent cage 210 may be constructed to expand to a predetermined outer diameter when deployed and have sufficient radial force to provide good embedment within the lesion while displacing the thrombus into the receiving space. A low level of scaffolding within the stent cage may be achieved by minimizing the potential surface contact area between the interconnected cage struts 224 and the thrombus or lesion. In one example, a less dense cell network with fewer struts may be utilized. In another example, the struts of the cage structure may be curved radially inward toward the longitudinal centerline or axis of the device in an oscillating, cyclical manner to obtain a localized reduction in the force on the thrombus and the contact area with the thrombus. Localized reduction may also be obtained by aligning multiples axially and / or radially between the distal and proximal ends 218 and 216 of the cage.

[0041] The raw material of the stent cage 210 can take many forms, such as wires, strips, sheets, or tubes. The expandable body of the stent cage can be made of a material capable of automatically recovering its shape when released from a highly strained delivery configuration. Superelastic shape memory materials such as Nitinol or alloys with similar properties are particularly suitable. These materials have sufficient elastic strain capacity so that the elastic limit is not exceeded when the cage is constrained in a collapsed delivery configuration within a microcatheter or outer access catheter. This elastic strain capacity allows the cage to be effectively spring loaded within the outer catheter so that it can self-expand when deployed from the distal end of the outer catheter. In another example, the framework can be constructed from wires, allowing the use of non-superelastic materials such as stainless steel alloys, since the wires would be free to move independently of each other.

[0042] In one example, a tube or sheet of Nitinol can be laser cut and then heat set to form the framework of struts and connectors. This tubular structure can be heat treated to a suitable temperature on a mandrel to stress relieve the structure and conform the tube to the shape of the mandrel. In these ways, the elastic properties of the stent braid can be controlled so that the stent can aid in the implantation process and maintain stiffness and strength over the desired life of the implant. The wraps of the braided strands can also be dense enough to provide a stable configuration that can support the entire inner diameter of a vessel when implanted.

[0043] The stent cage 210 may be bare metal, or the material may be coated with a non-pharmacological coating, such as silicon carbide, carbon, and titanium-nitride-oxide. The coating may be hydrophilic or have additives that are effective in increasing the lubricity of the mesh braid of the stent placement device 112 to allow for a more atraumatic navigation of the vasculature. In another example, the coating may be a hydrogel or may contain soluble particles in a polymer matrix that may soften or completely dissolve when exposed to an aqueous medium such as blood. In other cases, the stent is coated with a biodegradable drug-eluting coating designed to inhibit restenosis. For example, these may be antiplatelet or anticoagulant drugs. These drugs elute the coating from the matrix when exposed to aqueous media, helping to prevent the implanted stent 128 from forming potential nidus for future clot formation.

[0044] The interconnected struts 224 may be formed as a monolithic structure or may be assembled as a combination of substructures. The distal most crown or wavy struts 226 may have a flared shape. The receiving space 220 within the lumen of the stent cage may be made large enough that there is enough room for the thrombus to be forced through or by the surrounding tissue without significantly compressing the surrounding tissue and changing the coefficient of friction.

[0045] In the majority of cases, the device may be used strictly to perform a thrombectomy procedure. However, in perhaps 40% of cases with certain patient populations, it may be desirable to scaffold and expand the identified area of ​​stenosis. After recanalization, the separation point may be configured to release the stent cage from the remainder of the device. The outward radial force exerted on the wall by the stent cage, which the vessel may hold stationary to maintain the fidelity of the lumen flow path, may be used to locally support the vessel and even expand the vessel. Once the stent cage has been implanted as a stent, the remainder of the device, including the capture section 110 and the fragment protection element 310, may be removed from the patient.

[0046] 4 illustrates where the stent cage 210 is a stent implanted within the blood vessel 20 to expand the region of the stenosis 50. The radial dimension of the stent cage can be selected to adjust the radial force exerted such that the radial dimension 26 of the vessel lumen 22 within the lesion is restored to a percentage of the baseline radial dimension 24 of the unaffected region adjacent the lesion. The percentage can depend on the amount of plaque that has accumulated within the lesion. Friction due to the radial force exerted by the expanded stent cage can maintain the longitudinal position of the stent within the vessel.

[0047] The capture section 110 may have a proximal elongate member 124 and a distal filter element 314 for fragment protection, as shown in FIG. 5. The elongate body may have a proximal end 116, a distal end 118, a longitudinal axis 122, and a proximal shaft 112. The longitudinal axis 122 may or may not coincide with the longitudinal axis 228 of the stent cage when the device is deployed. The elongate body may take a number of shapes and may have tapered sections, flared sections, and open or closed ends. The elongate body may be configured to have an expanded diameter in the region of about 1.5 mm to 5.0 mm. The elongate body may have an expandable framework of struts 120 or crowns configured to grasp and remove occlusive clots. The struts may have bends that form necked regions that allow different longitudinal sections of the elongate body to exert varying radial forces against the clot. The variable radial force allows the elongate body to establish a firmer grip on the clot between the sections making it easier to initially disengage from the vessel wall. The filter element may expand radially greater than the elongate body 124 in the deployed state.

[0048] In another example, when expanded to the deployed configuration, the elongate body 124 of the capture section 110 can have a substantially tubular shape disposed about the longitudinal axis 112 and can be configured to exert a strong radial force to open a flow lumen through the clot. This small flow passage may initially restrict flow so that blood supply is gradually re-established to the affected area to reduce the risk of reperfusion injury. Alternatively, the elongate body 124 of the capture section 110 may have a planar structure that may oscillate periodically or extend helically about the longitudinal axis 112. Configured in this manner, the elongate body can expand and contract in response to the forces of a thrombectomy procedure to grasp or clamp a clot between adjacent apexes of the structure for extraction from the blood vessel.

[0049] FIG. 6 is an end view of the example capture section 110 and fragment protection element 310 of FIG. 5 in an expanded deployed configuration. In one configuration, at least a portion of the fragment protection element may expand more than the clot capture section to provide a downstream surface that blocks dislodged clot fragments. In the illustrated example, the fragment protection element may have a framework of struts 316 extending radially outward from a central fragment protector hub 320 in a spoke-type configuration to form a physical barrier to prevent distal migration of debris from the thrombectomy procedure. The strut framework may be a flexible or rigid structure, or the struts may be configured to hinge or fold about a plane to occupy more space downstream of the capture section. The hub may be a simple tubular member extending distally from the capture section, or it may be a wound wire bundle or mesh. The framework struts 316 may have flared or bulging sections and may be configured in an overlapping spiral pattern for increased fragmentation protection.

[0050] As with some previous examples, further designs for thrombectomy and stenting with dual expandable members are disclosed. In FIG. 7, a device is shown that may have a first inner expandable member that may function as a clot capture section 110 and a second outer expandable member 210 that may function as a stent. The inner member may be a stentriever configured substantially within the lumen of the outer member. The inner member may have an expandable framework of struts or crowns configured to grip and remove occlusive clots. The properties of the inner and outer members may be adjusted independently of each other. For example, in a design where both members comprise connected struts, the shape and porosity level of the strut framework 120 of the inner member may be significantly different from the interconnected struts 224 of the outer member. In this way, the stiffness and radial force of the inner member may be configured to grip the clot, while the outer member is configured to scaffold the vessel.

[0051] The receiving openings of the outer cage 210 may be enlarged so as to offer little resistance to the movement of the clot relative to the cage. The clot may be locally compressed when the outer stent cage is expanded, and the receiving openings allow the clot or debris to escape compression by displacing into the cage's internal receiving space 220. This reduces the radial force exerted by the stent cage on the vessel in the region of the stenosis, which means less force is required to retrieve the clot, resulting in less vessel damage and less tension on the distal vascular bed. The radial force of the cage may be strong at a small diameter, similar to a compression spring, to displace the clot. The radial force may be weaker at a larger diameter to gently press against the lesion and vessel wall.

[0052] The distal end 118 of the inner member capture section 110 may extend distal to the distal end 218 of the outer cage 210. Applied suction may urge the clot proximally to be engaged by the strut framework 120 of the capture section.

[0053] The inner and outer members may be delivered from the same microcatheter 70 and guided through the lumen of the guide or access catheter 30 to a target site within the patient's vessel. The device may have separate shafts that allow independent movement of the inner and outer members. The first proximal shaft 112 may articulate the capture section 110 and the second proximal shaft 212 may articulate the stent cage 210. Having separate shafts may allow the user to accommodate situations where, for example, the axial position for grasping the clot is slightly different than the axial position that is most effective for restoring the flow path. The use of separate shafts may allow the clot to be retrieved independent of the deployment of the stent cage. After retrieval of the clot, the physician may choose to leave the stent cage in place for a short period of time to assess the risk of reocclusion of the vessel before deciding whether to detach and deploy the stent cage as an implant. If the physician chooses not to deploy the stent cage, it may be resheathed and removed from the patient.

[0054] FIG. 8 shows the device of FIG. 7 deployed in a portion of a blood vessel 20 having an occlusive thrombus 40 lodged within a stenotic lesion 50. When the maximum radial dimension of the target lesion is smaller than the maximum radial dimension of the stent cage 210, the cage can be configured to exert an outward radial force when deployed within the lesion. The outer cage can dilate the lesion while the capture section 110 expands to grip the thrombus. A radiopaque marker or coil 67 can mark the distal end of the end of the device so that a user can adjust the longitudinal position of the capture section using the second proximal shaft 212 independent of the radial force exerted by the outer cage. As the stent cage expands, it can begin to compress and displace the thrombus through the cells formed by the struts 224. The large cells can allow the thrombus to escape compression by displacing a significant portion of the thrombus through the cell openings in the wall of the stent cage. The thrombus can also be drawn through the open distal port of the cage by suction.

[0055] 9 shows another example of a bi-layer device in which the distal end 118 of the elongate body 124 of the capture section 110 overlaps longitudinally with the proximal end 216 of the stent cage 210. As with the other examples, the stent cage may have a plurality of interconnected struts 224 that form a circumferential network of closed cells. The capture section 110 may be secured to a shared shaft 64 at its proximal end 116, while the stent cage 210 may be secured distally to the shaft 64 at a separation point 214. The proximal capture section 110 may expand to a maximum radial size 114 that is approximately equal to or less than the maximum radial size 222 of the distal stent cage. In another configuration, the capture section 110 may expand to a maximum radial size 114 that is slightly greater than the maximum radial size 222 of the stent cage 210, such that the capture section is radially constrained by the stent cage.

[0056] The maximum radial dimension of the stent cage when expanded may be at least 20% greater than the maximum radial dimension of the expanded capture section. In other examples, the stent cage may be more than twice the diameter of the capture section. The stent cage may have a network of interconnected struts 224 along the distal length of the device that form large closed cells for low radial forces.

[0057] The capture section may be a framework of struts 120 organized into a series of adjacent segments. The struts may be organized into closed cells or may include one or more bends or undulations along their length to engage various portions of the clot or thrombus. The cells and / or bends may be different sizes in different longitudinal sections of the capture section. In one example, each segment of the capture segment may consist of a flat pattern of struts 120 and cells that are then arranged into a wave or wavy shape 312 when viewed from the side. Alternatively, adjacent segments may be aligned longitudinally to collapse the struts of the segment when subjected to a longitudinal tensile or compressive load. Such a change in the radial force exerted by the capture section may cause the clot to become embedded or pinched between various portions of the strut framework. Interpenetration and pinching may also be induced when the device is later retracted and folded back into the intermediate or access catheter after capturing the clot. The clamping action can be useful to increase the grip of the device on the fibrin-rich clot and may elongate the clot and pull it away from the lesion or vessel wall, thus reducing the required removal force.

[0058] The device may have a fragment protection element 310 located downstream of the capture section 110 and inside the stent cage 210. A filter element 314 of the fragment protection element 310 provides a physical barrier against any embolism from the clot retrieval procedure. A flexible connecting member 312 may connect the filter element 314 to the distal end 118 of the capture section, meaning that the longitudinal position of the protection element is determined by the proximal capture section shaft 112.

[0059] In another example of a clot retrieval and stent placement device 200 illustrated in FIG. 10, an expandable outer cage may also be configured to engage and extract a clot. The device may have an outer cage 210 having a structure for embedding and capturing an occlusive clot when expanded from a delivery configuration to a deployed configuration. The outer cage may have a proximal end 216, a distal end 218, and a shaft 212 for articulation of the device. A separation point 214 may be located at the intersection of the distal ends of the shafts, and the proximal end of the outer cage may be configured to disengage the outer cage and embed it as a stent.

[0060] The outer cage 210 may have a series of interconnected struts 224 that form a circumferential network of large closed cells. The interconnected struts may include connecting members that extend through the interior of the outer cage to provide additional surfaces for capturing and gripping the clot. The struts may be shape-memory, such as Nitinol, that allows them to expand to a desired maximum radial size 222 when deployed in a vessel. The interconnected struts cut in such a manner that they engage and grip the clot during a standard thrombectomy procedure. During this engagement, the clot may be partially disposed within the cell openings of the interconnected struts 224 and partially disposed within the receiving space or inner lumen 220 of the outer cage.

[0061] Similar to previous designs disclosed in this description, the retrieval and stenting device 200 may have a fragment protection element 310 that may be deployed proximate the distal end of the outer cage to provide a physical barrier to prevent dislodged debris from migrating downstream during the clot retrieval procedure. The fragment protection element may be connected to the shaft 212 by a flexible connecting member 312. The connecting member may be an extension of the shaft 212 or may itself have struts or a wavy, corrugated pattern that may help grip the clot as it expands and contracts under the forces of clot retrieval.

[0062] Once a retrieval attempt with the device 200 has achieved a desired level of vascular recanalization, the physician may wish to further treat the stenotic region, such as an ICAD lesion. The device may be flushed with saline or other media and reintroduced to the target site using a thrombectomy delivery system or other suitable means known in the art. Upon advancement across the lesion, the outer cage 210 may be expanded and then released by actuating the detachment point 214. The maximum diameter or radial size 222 of the outer cage when deployed may be designed to minimize chronic outward forces imparted to the stenosis, which is important for vessels with many fragile neurovasculature. In one example, the maximum diameter of the deployed outer cage may be configured to be approximately 2.5 mm, but in other examples, may be up to 4.0 mm. Once implanted as a stent, the shaft 212 may be retracted to pull the connecting members 312 and remove the fragment protection element 310 from the patient.

[0063] The outer cage 210 and capture section 110 shown in the figures and described herein are used to illustrate a single embodiment of the invention. Of course, the invention may be applied to outer cages and capture sections of various shapes and sizes, and may be made from a single section or from multiple sections.

[0064] 11a-11e show various alternative designs for the construction of the fragment protection element 310. The fragment protection mechanism can be created by the attachment of shaped wires or struts 316. The wires or struts can be in a number of shapes or orientations to better cover the open end of the stent cage when the device is deployed. In some embodiments shown in Figs. 11a, 11c, and 11d, the wires or struts are organized into a three-dimensional structure, where the wires or struts flare outward radially to form a shape equal to or larger than the cross section of the inner expandable capture section of the device. The wires or struts can be an interconnected network, or they can form a spoke-type arrangement extending from a common hub 320 of the fragment protector. In another set of examples shown in Figs. 11b and 11e, the wires or struts are interwoven with each other to create a braided fiber filter mesh 318. The mesh may be woven in an organized pattern, or the wires or fibers may be intertwined into bundles.

[0065] Figures 12a-12d illustrate one possible sequence of use for the devices disclosed herein. Figure 12a illustrates an example of a device navigated to a target vessel 40 within a neurovasculature. A delivery system can access the site using an access catheter 30, and the device can be loaded into a microcatheter 70 for deployment. The target site may be an occluded vessel as shown, with an occlusive clot 40 lodged in an area where the vessel lumen 22 is also narrowed by a region of intracranial stenosis in the form of a lesion 50 due to atherosclerotic plaque buildup.

[0066] The microcatheter 70 may be advanced until it is positioned distal to the clot 40. Once in place, the microcatheter may be retracted proximally, while the stent cage 210 and capturing section 110 are allowed to expand within and on either side of the clot, as shown in FIG. 12b. Expansion of the stent cage displaces the clot and expands the lumen 22 of the blood vessel 20, thereby restoring flow. The struts of the capturing section 110 engage and grasp the clot.

[0067] In FIG. 12c, the capture section 110 begins to extract the clot 40 proximally from the target vessel 20. To maintain a firm grip on the clot and avoid loss and migration of fragments, extraction may involve suction directed from a separate aspiration catheter or from the guide or access catheter 30. The capture section structure may have adjacent segments with different shapes such that the force exerted on the clot is variable when the capture section is again retrieved into the intermediate or access catheter. The variation in force between adjacent sections may result in a more effective clamping action, especially in maintaining a grip on firm or irregular clot morphologies. In some cases, the stent cage 210 may be retracted into the access catheter 30 together with the capture section 110, or may be manipulated and positioned separately when multiple shafts are used. Alternatively, the device may be held in place and at least partially resheathed by advancing the access catheter distally.

[0068] Once the stenotic region has been identified, the user has the ability to disengage the stent cage 210 as an implant within the lesion 50, as shown in FIG. 12d. After the occlusive clot has been safely retracted, the device can be driven back across the stenosis, if not already in place, so that the stent cage is aligned with the lesion within the vessel. The outer diameter of the stent cage and the shape of the outer cage framework are selected so that an effective amount of support is provided to the target vessel 20 so that a reconstituted flow path can be maintained through the narrow stenotic region. For example, the desired flow path diameter in the stented region is achieved when a contracted first diameter in the portion of the vessel containing the lesion is increased to 75% of a second diameter in the portion of the vessel adjacent to the first diameter. Upon completion of the procedure, the remainder of the bilayer device can be withdrawn from the patient.

[0069] 13 and 14 are each a flow diagram including method steps for performing a mechanical thrombectomy procedure, which may be accomplished by any of the devices and / or instruments described herein.

[0070] Referring to method 1300 as outlined in FIG. 13, at step 1310, access to a patient's blood vessel is obtained by conventional techniques and an access catheter and a microcatheter having a hollow inner lumen are positioned in the blood vessel in a neurovasculature having a stenotic lesion and an occlusive clot. The access catheter may be an outer guide catheter or an aspiration catheter as described herein or alternatives known to those skilled in the art. A dual purpose thrombectomy and stenting device may be positioned within the microcatheter. At step 1320, the device may have a self-expanding outer cage with a plurality of large cell openings and a separation point configured to release the outer cage from the remainder of the device and implant it as a stent. At step 1330, the second layer may include an inner capture section within the outer cage, the inner capture section having a maximum radial dimension less than, equal to, or slightly greater than the maximum radial size of the outer cage depending on the application. The capture section may have an expandable network of struts to grasp the clot and remove it from the blood vessel.

[0071] The device may further include additional components to facilitate endovascular procedures. At step 1340, a fragment protection element may be placed distal to the capture section to occupy space across the vessel lumen and prevent distal release of dislodged fragments during the procedure. The protection element may be attached to the capture section by a flexible shaft or wire and may take any of a number of forms well known to those skilled in the art for this purpose. In addition, a further step 1350 may include adding one or more radiopaque markers at key points on the device so that they are easily visible under fluoroscopy during the procedure. For example, markers may be added to the proximal and distal ends of the device to mark the final treatment point during surgery.

[0072] Referring to method 1400 as outlined in FIG. 14, in step 1410, the microcatheter is advanced from the access catheter toward and across the occlusive clot, sheathing the outer cage and capture section and expanding from the microcatheter. The large cells of the outer cage displace the clot into the interior receiving space. In step 1420, the capture section expands to engage and grasp the clot. Step 1420 may also include retracting the thrombectomy and stenting device, bringing the captured clot proximally into the lumen of the microcatheter and / or access catheter for removal from the patient. If additional capture attempts are required to sufficiently clear the vessel, the aforementioned steps may be repeated as necessary.

[0073] To treat a narrow stenosed area within a blood vessel, the user can redeploy the outer cage and capture section to the target site and align them with the lesion, as in step 1430. A detachment point can be actuated to leave the outer cage in an expanded state as an implanted stent within the blood vessel. In steps 1440 and 1450, the remainder of the device, including the capture section, can be retracted into an access catheter and removed from the patient.

[0074] The present invention is not necessarily limited to the described examples, which may vary in configuration and details. The terms "distal" and "proximal" are used throughout the foregoing description and are meant to refer to a location and direction relative to the treating physician. Thus, "distal" or "distally" refers to a location away from or a direction away from the physician. Similarly, "proximal" or "proximally" refers to a location closer to or a direction toward the physician. Additionally, the singular forms "a," "an," and "the" include plural referents unless the context clearly dictates otherwise.

[0075] "Comprising" or "containing" or "including" means that at least the specified compounds, elements, particles, or method steps are present in a composition or article or method, but does not exclude the presence of other such compounds, substances, particles, or method steps, even if those other compounds, substances, particles, or method steps have the same function as the one specified.

[0076] In describing the exemplary embodiments, technical terms are utilized for clarity. Each term is intended to have its broadest meaning as understood by those skilled in the art, and is intended to include all technical equivalents that operate in a similar manner to achieve a similar purpose. It should also be understood that the reference to one or more steps of a method does not preclude the presence of additional method steps or intervening method steps between those steps that are explicitly identified. Some steps of a method can be performed in a different order than described herein without departing from the scope of the disclosed technology. Similarly, it should also be understood that the reference to one or more components in an apparatus or system does not preclude the presence of additional components or intervening components between those components that are explicitly identified. For clarity and conciseness, not all possible combinations have been listed.

[0077] The term "about" or "approximately" as used herein with respect to any numerical value or range of numerical values ​​indicates a suitable dimensional tolerance that allows a portion of a component or a collection of components to function according to its intended purpose as described herein. More specifically, "about" or "approximately" may refer to a value range of ±20% of the recited value, for example, "about 90%" may refer to a value range of 71% to 99%.

[0078] The descriptions contained herein are examples of embodiments of the present invention and are not intended to limit the scope of the present invention in any way. Although specific examples of the present invention are described, various modifications to the apparatus and method can be made without departing from the scope and spirit of the present invention. For example, the examples described herein refer to specific components, but the present invention includes other examples that utilize combinations of various components to achieve the described functionality, utilize alternative materials to achieve the described functionality, combine components from various examples, combine components from various examples with known components, and the like. The present invention contemplates the replacement of component parts illustrated herein with other well-known commercially available products. These modifications will be apparent in many cases to those skilled in the art to which the present invention pertains, and are intended to be within the scope of the following "claims."

[0079] [Embodiment] (1) A device for treating occlusions and stenotic lesions in the vascular system, comprising: A capture section, An elongated body; A proximal end portion; A distal end portion. a folded delivery configuration; an expanded deployed configuration; and a stent cage having a collapsed delivery configuration and an expanded deployed configuration; The stent cage is configured to be separable from the device to remain implanted within the lesion when the capture section is removed from the lesion. (2) The device of embodiment 1, wherein the stent cage is a stent. (3) The device of embodiment 1, wherein the capture section is a stentriever configured to engage one or more portions of the occlusive thrombus upon movement from the folded delivery configuration to the expanded deployed configuration. (4) The device of embodiment 1, wherein the stent cage and the capture section share a common proximal shaft. (5) The device of embodiment 1, wherein the stent cage further comprises a plurality of interconnected struts forming a circumferential network of closed cells.

[0080] (6) The device of embodiment 5, wherein at least two of the plurality of interconnected struts are longitudinally aligned. (7) The device of embodiment 1, wherein the capture section comprises a strut framework forming an outer network of closed cells, at least a portion of the strut framework configured to embed and clamp at least a portion of the thrombus in the expanded, deployed configuration when the capture section is retracted back into the outer catheter. (8) further comprising a fragmentation protection element at the distal end of the capture section, the fragmentation protection element comprising: A connecting member; 2. The device of embodiment 1, further comprising a distal fragment filter expandable to at least the same radial size as the capture section in the expanded deployed configuration. (9) The device of embodiment 1, wherein the stent cage is configured to exert an outward radial force when deployed to expand within the lesion. (10) The device of embodiment 1, wherein a first proximal shaft is capable of articulating the capture section and a second proximal shaft is capable of articulating the stent cage.

[0081] (11) A device for treating occlusive thrombi and stenosed regions in a vascular system, said device comprising: A proximal shaft; An outer cage comprising: an outer cage having a substantially tubular structure having a folded delivery configuration, an expanded deployed configuration, and a maximum radial dimension; the outer cage is configured to exert an outward radial force when deployed to expand within a stenotic region; The device, wherein the outer cage is further configured to be detachable from the device to remain implanted in the stenosis. (12) The device of embodiment 11, wherein in the expanded, deployed state, the maximum radial dimension of the outer cage when expanded is about 6.0 mm in diameter. (13) The device of embodiment 11, wherein the distal end of the outer cage extends to a radial dimension greater than the maximum radial dimension of the outer cage. (14) The device of embodiment 11, wherein the outer cage is an implantable stent. (15) The device of embodiment 11, wherein the outer cage further comprises a structure of interconnected struts.

[0082] (16) The device of embodiment 11, further comprising a distal fragment protection element fixedly connected to the proximal shaft by a connecting member. (17) The device of embodiment 15, wherein the interconnected struts of the outer cage are configured to engage at least a portion of the thrombus in the expanded, deployed configuration. (18) The device of embodiment 15, wherein the interconnected struts of the outer cage are configured to embed and clamp at least a portion of the thrombus in the expanded, deployed configuration. (19) A method for treating a stenotic lesion and an occlusive thrombus, comprising: positioning an access catheter and a microcatheter within a blood vessel having the stenotic lesion and the occlusive thrombus, the access catheter and the microcatheter including hollow inner lumens; positioning a self-expanding outer cage within the microcatheter, the outer cage being sized to exert an outward radial force on the lesion, the outer cage including a plurality of large cells and a separation point configured to embed the outer cage within the blood vessel; positioning an expandable capture section with the outer cage, the capture section having a collapsed delivery configuration and an expanded deployed configuration; deploying the outer cage and the capture section from the microcatheter to allow passage of the thrombus and / or fragments radially inward through cells of the outer cage; deploying the capture section from the microcatheter to capture the thrombus; separating the outer cage at the separation point to leave the outer cage in the expanded configuration within the vessel as a stent; retracting the capture section into the access catheter along with the thrombus; and withdrawing the microcatheter, the access catheter, and the capture section from the patient along with the captured thrombus. (20) The method of embodiment 19, further comprising the step of providing a distal fragment protection element.

Claims

1. 1. A device for treating occlusions and stenotic lesions in the vascular system, comprising: A capture section, An elongated body; A proximal end portion; A distal end portion. a folded delivery configuration; an expanded deployed configuration; and a stent cage having a collapsed delivery configuration and an expanded deployed configuration; a fragment protection element at the distal end of the capture section; the stent cage is configured to be separable from the device to remain implanted within the stenotic lesion when the capture section is removed from the stenotic lesion; The fragment protection element comprises: A connecting member; a distal fragment filter expandable to at least the same radial size as the capture section in the expanded deployed configuration; The device, wherein the connecting members connect the fragment protection element to the capture section, the connecting members defining a wavy, corrugated pattern.

2. The device of claim 1 , wherein the stent cage is a stent.

3. The device of claim 1 , wherein the capture section is a stentriever configured to engage one or more portions of the occlusion upon movement from the collapsed delivery configuration to the expanded deployed configuration.

4. The device of claim 1 , wherein the stent cage and the capture section share a common proximal shaft.

5. The device of claim 1 , wherein the stent cage further comprises a plurality of interconnected struts forming a circumferential network of closed cells.

6. The device of claim 5 , wherein at least two of the plurality of interconnected struts are longitudinally aligned.

7. 2. The device of claim 1, wherein the capture section comprises a strut framework forming an outer network of closed cells, at least a portion of the strut framework configured to embed and clamp at least a portion of the occlusion in the expanded, deployed configuration when the capture section is pulled back into an outer catheter.

8. The device of claim 1 , wherein the stent cage is configured to exert an outward radial force when deployed to expand within the stenotic lesion.

9. The device of claim 1 , wherein a first proximal shaft is capable of articulating the capture section and a second proximal shaft is capable of articulating the stent cage.

10. 1. A device for treating occlusive thrombi and stenosed regions within the vascular system, the device comprising: A proximal shaft; An outer cage comprising: an outer cage having a substantially tubular structure having a folded delivery configuration, an expanded deployed configuration, and a maximum radial dimension; a distal fragment protection element fixedly connected to the proximal shaft by a connecting member; the outer cage is configured to exert an outward radial force when deployed to expand within the narrowed region; the outer cage is further configured to be separable from the device to remain implanted in the stenotic region; The apparatus, wherein the connecting members form a wavy corrugated pattern.

11. 11. The device of claim 10, wherein in the expanded deployed state, the maximum radial dimension of the outer cage upon expansion is 6.0 mm in diameter.

12. The device of claim 10 , wherein a distal end of the outer cage flares to a radial dimension greater than the maximum radial dimension of the outer cage.

13. The device of claim 10 , wherein the outer cage is an implantable stent.

14. The device of claim 10 , wherein the outer cage further comprises a structure of interconnected struts.

15. The device of claim 14 , wherein the interconnected struts of the outer cage are configured to engage at least a portion of the occlusive thrombus in the expanded, deployed configuration.

16. The device of claim 14 , wherein the interconnected struts of the outer cage are configured to embed and clamp at least a portion of the occlusive thrombus in the expanded, deployed configuration.

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