Thrombectomy and stent implantation system

Abstract

The present invention is entitled "Thrombectomy and Stent Implantation System". The present invention provides a design capable of both mechanical thrombectomy and stent implantation for the treatment of occlusions in the cerebral vasculature, which provides a three-catheter setup. A first outer catheter has the largest diameter and can serve as a guide catheter, while also serving as a sheath for the other catheters. A second deployment catheter can be configured for aspiration of the occlusion and can include a proximal stepped or recessed segment at the distal tip that can act as a housing for a woven expandable stent. The outer diameter of the stepped segment can be lined with an inflation device having a woven stent disposed on its top. Inside the second deployment catheter is a microcatheter that can deliver a mechanical thrombectomy device to the target site to retrieve the occlusion in the vessel, after which the stent can be expanded and implanted in the vessel.

Description

Technical Field

[0001] This invention relates generally to apparatus and methods for removing obstructions and treating cerebral vascular stenosis during endovascular medical treatment. More specifically, this invention relates to multi-catheter systems for combining procedures of mechanical thrombectomy and stent implantation. Background Technology

[0002] Atherosclerosis is caused by lesions that narrow and reduce the space within the lumen of blood vessels in the vascular system. These lesions are typically composed of plaques, which can be fat, cholesterol, calcium, or other components of the blood. Severe occlusion or blockage can impede the flow of oxygenated blood to different organs and parts of the body, leading to other cardiovascular diseases such as heart attacks or strokes. Narrowing or stenosis of blood vessels increases the risk that clots and other embolisms may become lodged in these locations, especially in neurovascular vessels that are already very small in diameter. Intracranial arteriosclerosis (ICAD) is the narrowing of arteries and vessels that supply blood to the brain and is the most common approximate mechanism of ischemic stroke.

[0003] Treatment of vascular occlusion is well known in the art. Methods may include the use of drugs, such as anticoagulants or antiplatelet agents, and medical procedures, such as surgical endarterectomy, angioplasty, and stent implantation. Recent successes in endovascular recanalization (ERT) have been largely due to the further development of safe thrombectomy devices. Devices such as stent thrombectomy devices, 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 occluded thrombus. If significant stenosis is also present at the site of occlusion, adequate recanalization may not occur, increasing the need for stent implantation.

[0004] Treatment methods for addressing clots and lesions in neurovascular structures depend on the degree of stenosis, the shape of the target occlusion site (i.e., the main trunk, branches, etc.), and the patient's overall condition. Mechanical procedures typically involve using a medical device to retrieve the occlusive clot, followed by the use of a balloon and stent to open the narrowed artery. After using a stent thrombectomy device or other clot retrieval device, a balloon is delivered to the target site and inflated to dilate the stenosis. The balloon can then be removed and exchanged via a catheter used for stent delivery. If necessary, once the stent is in place, the balloon can be inflated inside the stent to firmly press the stent frame struts against the inner wall of the vessel.

[0005] However, several significant challenges exist in interpreting and diagnosing stenosis. This is especially true in the very small and tortuous vessels of the cerebral vascular system. During the treatment of a stroke or transient ischemic attack, it may be unclear whether the occlusion is solely due to a blood clot or also involves stenosis. Identifying stenotic lesions can be difficult because it is challenging to differentiate them from clot-related and other embolic occlusions via baseline angiography. In many cases, the presence of stenosis is only identified after initial treatment options have been selected and an ERT procedure has been performed, and the devices and methods used to remove the occlusion are often different from those used to treat the stenosis and implant a stent into the vessel.

[0006] In cases involving both blood clots and stenosis, physicians often need to replace catheters, devices, and usually guidewires after removing the clot. Therefore, devices that provide surgical flexibility are invaluable, as the need for multiple passes and deliveries can be cumbersome, and these mechanical procedures also create the possibility of releasing additional debris into the vascular system. Such debris may include, but is not limited to, blood clots, plaques, and other embolic fragments.

[0007] There is a persistent need to shorten the time from onset to surgery to reduce ongoing damage in patients with ischemic stroke. Therefore, new systems and devices are still needed to continue addressing and improving these treatments. The present invention is designed to provide an improved system and method for treating cerebral vascular systems with a combination of clots and stenosis, addressing the aforementioned deficiencies. Summary of the Invention

[0008] The purpose of this design is to provide systems, devices, and methods that meet the aforementioned requirements. Generally, the system of this invention provides a three-catheter setup. The first catheter has the largest diameter and serves as a guiding catheter, as well as a deployment sheath for the other catheters. The second catheter can be configured for aspiration and may include a proximal stepped or recessed segment at its distal end, which can act as the shell of a braided, inflatable stent. The outer diameter of the stepped segment may be lined with a balloon or other inflatable member on its top, upon which a flexible stent is placed. The interior of the second catheter is a microcatheter that can deliver a mechanical thrombectomy device to the target site to retrieve the occlusion in the blood vessel.

[0009] An exemplary system for removing clots from a blood vessel and implanting a stent may include a sheath member, a deployment catheter, and a microcatheter. These three catheters may be substantially concentric. A source may be configured to aspirate the internal lumen of the sheath member and / or the deployment catheter. The deployment catheter may have a lumen and an outer surface and be disposed within the lumen of the sheath member. The deployment catheter may have a flexible distal portion and a recessed region located on its outer surface, the recessed region having an outer diameter smaller than the outer diameter of the deployment catheter in the region adjacent to the recessed region. The flexible region enhances deliverability and surrounds the most distal region of the deployment catheter. For example, the flexible region may extend 15 cm to 30 cm proximally to the distal end.

[0010] The inflatable device and stent implantation device can be externally connected to a recessed area on the outer surface of the deployment catheter. The recessed area provides support for the inflatable device and stent implantation device on the outer surface and allows for a thinner system. Similar to conventional methods known in the art for balloon angioplasty, the stent implantation device can be self-expanding, or the inflatable device can be used to inflate the stent implantation device within a stenotic lesion and implant it as a stent. Inflation can be achieved by utilizing an inflatable lumen that extends along the length of the deployment catheter. The inflatable device can also be used to dilate the vessel during any part of the stent implantation procedure.

[0011] To retrieve blockages in a blood vessel, the system can be used as an aspiration catheter for removing occlusive clots using suction. In cases where the clot has become lodged in the vessel or in a restricted, narrowed area, the system can retrieve the clot by aspirating it into the lumen of a deployment catheter or by utilizing other mechanical thrombectomy techniques. For example, the system's third catheter can be a microcatheter located within the lumen of the deployment catheter and configured to deliver a mechanical thrombectomy device to the target occlusion. The mechanical thrombectomy device can be any of many commercially available designs. In one example, the expandable clot retrieval device has a collapsed configuration within the microcatheter but self-expands into an enlarged deployment configuration as it exits the lumen at its distal end. The clot engagement portion of the device can have an expandable member that, upon deployment, forms a flow lumen through the occlusion, while also having multiple embedded struts to provide strong clamping on the clot for the initial step of detaching it from the vessel. For subsequent clot removal, the device can be retracted proximally into the deployment catheter using suction. The device and clot can then be withdrawn from the patient through the lumen of the catheter, or they can be pulled back far enough to retain a more solid clot at the end of the larger catheter so that they can be withdrawn one after the other.

[0012] In another example, a thrombectomy and stent implantation system for removing clots from a blood vessel and implanting a stent may include a sheath member, a deployment catheter located in the lumen of the sheath member, and a microcatheter located in the lumen of the deployment catheter. The sheath member, deployment catheter, and microcatheter may be concentric with each other and configured to move independently along the longitudinal axis of the system. An expandable stent implantation device may be coupled to the outer surface of the deployment catheter. The microcatheter may include a clot retrieval device for capturing and removing clots from the blood vessel.

[0013] The body of the stent implantation device may have a braided or interconnected pattern with a matrix of sufficient density to support the vessel wall during implantation. The stent's mesh can be made of medical-grade stainless steel (such as 316SS) or cobalt or cobalt-chromium alloy. In other examples, the stent may have a polymer or partially polymeric construction. The mesh braid may also be made of shape memory material that allows it to self-expand upon deployment. The stent may be bare metal, or the material may be coated with a non-pharmacological coating, such as silicon carbide, carbon, and titanium nitrides and oxides. In other cases, the stent has been coated with a biodegradable drug-eluting coating designed to inhibit restenosis. These coatings may be antiplatelet agents or anticoagulants to help prevent postoperative clot formation.

[0014] In one example, a portion of the outer surface of the deployment catheter may include a recessed region smaller than the size of another region of the deployment catheter adjacent to the recessed region. The recessed region may be integrally formed with the body of the deployment catheter, such as a notch or groove cut into the outer surface of the deployment catheter. For example, if the support structure for the deployment catheter is formed of a hypotube, the recessed region can be cut into the outer surface using a laser. Additional feature structures may also be cut into the surface to improve catheter flexibility and trackability. The inflatable stent member may be sized such that the member is located on or contained within the recessed region. In some cases, the system may also have an inflation device external to the stent implantation device on the outer surface of the deployment catheter. When the user wishes to implant the stent in a narrow area, the sheath member can be withdrawn to expose the stent implantation device. The inflation device can then be inflated to inflate the stent implantation device and apply radial force to the vessel wall.

[0015] Methods for using a system that provides flexibility for both mechanical thrombectomy and stent implantation are also provided. The method may include some or all of the following steps and variations thereof, and these steps are listed in a non-specific order. Access to the patient's vascular system is made using conventionally known techniques. A sheath member is positioned near the stenotic lesion and occlusive clot. A deployment catheter is positioned within the lumen of the sheath member. A microcatheter, including a thrombectomy device, is positioned within the lumen of the deployment catheter. A stent implantation device, including an inflation device and a stent, is positioned on the outer surface of the deployment catheter near its distal end. An aspiration source, such as a vacuum pump or syringe, is configured to guide aspiration through the lumen of one or both of the sheath member and the deployment catheter. Aspiration may be used for clot retrieval and to prevent further embolism.

[0016] The microcatheter and thrombectomy device extend toward and through the occlusion, while keeping the sheath, deployment catheter, and stent implantation device close to the lesion. The clot can be aspirated through the lumen of the deployment catheter. The clot is captured by deploying the thrombectomy device from the microcatheter while maintaining its position on the clot and retracting the microcatheter proximally. The microcatheter and the thrombectomy device with the captured clot can then be withdrawn into the lumen of the deployment catheter. Alternatively, the sheath member, deployment catheter, and stent implantation device can be advanced over the thrombectomy device to cross and align with the stenosis. Once in place, the sheath member can be retracted proximally to the lesion to expose the stent implantation device.

[0017] The inflator of the stent implantation device can be inflated, causing both the inflator and the stent to expand radially across the entire lesion. This radial expansion increases the diameter of the first portion of the vessel, including the lesion, to at least 75% of the diameter of the second portion of the vessel adjacent to the first portion. This process opens the vessel and reduces narrowing / occlusion caused by stenosis. Once the desired expansion is achieved, the stent can be released as an implant into place by deflating the inflator. Once the stent is in place, the remainder of the system can be removed from the patient.

[0018] The flexibility to utilize a single system, such as the current design, for mechanical thrombectomy and stent implantation can significantly reduce procedure time, leading to better clinical outcomes. This is especially true for stroke patients.

[0019] Other aspects and features of this disclosure will become apparent to those skilled in the art after viewing the following detailed description in conjunction with the accompanying drawings. Attached Figure Description

[0020] The above and other aspects of the invention will be further discussed with reference to the accompanying drawings, in which like numbers indicate the same structural elements and features in the various figures. The drawings are not necessarily drawn to scale; rather, the focus is on illustrating the principles of the invention. The drawings depict one or more specific embodiments of the device of the invention by way of example only and not by way of limitation. It is expected that those skilled in the art will be able to conceive of and combine elements from the various drawings to better meet the needs of the user.

[0021] Figures 1A to 1C This is a view of a three-catheter system according to various aspects of the present invention;

[0022] Figure 2 A system according to various aspects of the invention is shown located at a target site in a neurovascular system having a stenotic lesion and an occlusive clot;

[0023] Figures 3A to 3J Cross-sectional views are shown, illustrating the steps for performing mechanical thrombectomy and stent implantation using a system according to aspects of the present invention;

[0024] Figure 3A The system located at the target site and the microcatheter propelled through the occlusive clot according to various aspects of the invention are shown;

[0025] Figure 3B A thrombectomy device for capturing occlusive clots is shown, based on various aspects of the present invention.

[0026] Figure 3C The thrombectomy device according to various aspects of the present invention is shown, and the captured clot is aspirated back into the system;

[0027] Figure 3D The remaining portion of the system according to various aspects of the invention is shown being advanced to a position where the stent implantation device is aligned with the lesion;

[0028] Figure 3E The outer sheath component according to various aspects of the invention is shown retracting to expose the stent implantation device;

[0029] Figure 3F The invention illustrates an inflation device according to various aspects of the invention, which inflates a stent implantation device radially to widen a narrowed blood vessel.

[0030] Figure 3G The invention illustrates a method for continuously inflating an inflator to widen a blood vessel, according to various aspects of the invention.

[0031] Figure 3H The fully desired inflation of the inflation device according to various aspects of the invention and the stent embedded in the blood vessel are shown.

[0032] Figure 3I The invention illustrates how to deflate the inflation device to release the support into place according to various aspects of the invention;

[0033] Figure 3J The invention illustrates the removal of the remainder of the system to leave the implanted stent;

[0034] Figure 4 This is a flowchart outlining a method for performing mechanical thrombectomy and stent implantation procedures using a system, according to various aspects of the present invention. Detailed Implementation

[0035] Specific examples of the invention will now be described in detail with reference to the accompanying drawings, wherein like reference numerals indicate functionally similar or identical elements. The object of the invention is to provide a system or apparatus that offers physicians the advantage of operational flexibility to accommodate complications or unknown situations during endovascular surgery, such as when the occluded vessel has blood clots or potential stenosis areas not detected during angiography. These improvements allow for safer and faster access to complex areas of intracranial arteries to remove occlusions and reduce operative time.

[0036] Access to various intravascular vessels (whether coronary, pulmonary, or cerebral) involves well-known surgical procedures and the use of many routinely available commercially available accessory products. These products, such as angiographic materials, rotary valves, and guidewires, are widely used in laboratory and medical procedures. Their function and exact construction are not described in detail when used in conjunction with the systems and methods of the present invention described below. While this specification is primarily in the context of treating intracranial arteries, the system and apparatus can also be used in other bodily pathways.

[0037] Switch to the attached image. Figures 1A to 1C A system 100 capable of treating both occlusion and stenosis in a blood vessel is illustrated. As shown, the system 100 may include a first external guiding catheter or sheath member 102 having an internal lumen 104. A second deployment catheter 106 may be disposed within the lumen 104 of the sheath member 102. The sheath member 102 may serve as a guiding catheter for the system 100. The sheath member may also be used as a deployment sleeve for the deployment catheter, thereby protecting the remainder of the system during delivery and deployment.

[0038] like Figure 1CAs shown in the cross-sectional view, the deployment conduit 106 may have a distal end 107, an outer diameter D2, an outer surface 110, an internal lumen 108, and a flexible portion 111 circumferentially arranged in an annular pattern around the outer surface near the distal end. The deployment conduit may also have a stepped or recessed region 120 just proximal to the distal end 107 of the conduit, wherein the outer diameter D1 of the recessed region is smaller than the nominal outer diameter D2 of the deployment conduit. Therefore, the recessed region 120 may represent a groove or trench-like feature structure of the deployment conduit. The recessed region may be trapezoidal in shape with shallow corners, or may be of various other shapes, such as a semi-ellipse, as long as it is at least partially recessed from the outer surface of the deployment conduit 106 and surrounds at least a portion of the circumference.

[0039] The expandable stent implantation device 112 may be concentrically disposed around the outer perimeter of the externally uninflated inflation device 122 and close to the flexible portion 111 of the deployment catheter 106. The stent implantation device may be disposed within the flexible portion of the deployment catheter. In one example, the flexible portion 111 extends approximately 20 cm proximally from the distal end 107 of the deployment catheter 106.

[0040] Both the stent implantation device and the inflation device can be externally deployed with catheters. In one example, the inflatable stent implantation device 112 may be a stent having multiple elastic metal or plastic strands formed in a braided pattern. The stent implantation device may be self-expanding upon deployment from the system, or it may be inflated by means of the inflation device 122. In one example, the braid of the implantable stent of the stent implantation device is any of a variety of stainless steel alloys, or it may be constructed of a cobalt or cobalt-chromium alloy. In other examples, the stent braid may be made of polymer strands.

[0041] In other cases, the braid of the stent implantation device 112 may be made of nitinol or similar superelastic alloys with shape memory properties of a tubular structure having a predetermined outer diameter. The self-expanding stent implantation device can be actuated by retracting the outer sheath member 102 and may not require a separate inflation device 122 for deployment, although a balloon can still be used for pre- or post-dilation of the vessel during implantation. The tubular structure can be heat-treated on a mandrel to a suitable temperature to anneal the structure, thereby conforming the tube to the shape of the mandrel. In these ways, the elastic properties of the stent braid can be controlled, allowing the stent to self-expand to facilitate the implantation process. These properties are also important so that the stent can maintain stiffness and strength throughout the desired lifespan of the implantation. The winding of the braided strands can also be dense enough to provide a stable configuration that supports the entire circumference of the vessel during implantation.

[0042] In another example, the strands or struts of the support may extend longitudinally and be woven in a predominantly helical configuration, with the central axis or centerline 130 of the resulting tubular structure serving as a common axis. A first set of strands may be wound in one direction while axially displaced relative to each other. A second set of strands may be wound in a direction opposite to the first set of strands, while also axially displaced relative to each other.

[0043] The stent implantation device can also be bare metal or coated in various ways. The coating can be hydrophilic or contain additives that effectively enhance the lubricity of the mesh weave of the stent implantation device 112, enabling more non-invasive navigation of the vascular system. In another example, the coating can be a hydrogel or contain soluble particles in a polymer matrix that soften or completely dissolve upon exposure to an aqueous medium such as blood. In yet another example, the coating can have embedded pharmaceutical agents, such as antiplatelet agents, anticoagulants, anti-inflammatory agents, or antimicrobial agents. These agents can be eluted from the matrix of the coating upon exposure to an aqueous medium and help prevent the implanted stent from forming potential lesions, thus preventing future clot formation.

[0044] The inflation device 122 can be coupled, glued, or welded to the outer surface 110 of the deployment catheter. The inflation device 122 can have different constructions and be one or more balloon or tubular components configured to inflate and implant the stent implantation device 112 in an inflated state. Inflation of the inflation device can be achieved via an inflation lumen or tube 124 extending along the length of the deployment catheter 106. The inflation tube may occasionally be a separate component, but more commonly it is a hollow lumen incorporated into the internal construction of the deployment catheter. The inflatable stent implantation device and the inflation device can be externally connected together to the recessed region 120 of the deployment catheter 106, and this assembly can together have a nominal radial dimension similar to the nominal outer diameter D2 of the deployment catheter. During delivery of the system 100, the recessed region 120 within the flexible distal segment 111 of the deployment catheter 106 can serve as a shell for the inflation device 122 and the stent implantation device 112. The longitudinal length of the recessed region 120 allows the region to accommodate the most common neurovascular stent sizes.

[0045] The balloon can be constructed from any of a variety of materials, such as Chronoprene, polyurethane, nylon, PBx, or another thermoplastic elastomer. These materials make the balloon durable and thin. The final shape of one or more balloons can vary and be customized according to the shape of the stent implantation device 112. In one case, the balloon may have a substantially tubular profile with a tapered end.

[0046] It should be noted that when elements are described and visualized as tubular structures in the accompanying drawings and are generally shown as substantially straight cylindrical structures, the terms "tubular" and "tube" should be interpreted broadly as used herein. They are not intended to be limited to structures that are perfect cylinders or have a perfectly circular cross-section or a uniform cross-section over their entire length.

[0047] Figure 1C The diagram also shows a microcatheter 114 that can be positioned within the lumen 108 of the deployment catheter 106. The microcatheter is concentric with both the guide / shroud member 102 and the deployment catheter 106 about the central longitudinal axis 130 of the system 100. The sheath member, deployment catheter, and microcatheter are movable independently of each other. The occlusive clot 50 can be aspirated first using the deployment catheter, and then, if desired, the mechanical thrombectomy device 118 can be delivered and deployed using the microcatheter. The mechanical thrombectomy device can be any of many commercially available products. The device may have a clot retrieval device with a clot engagement portion that has a collapsed delivery configuration within the microcatheter and self-expands into an expanded deployment configuration once it emerges from the distal end 115 of the microcatheter. The engagement portion may have an expandable network of struts for clamping and removing the clot from the vessel. The shape of the network can be designed such that when the device 118 retracts, the struts apply force to the clot 50 in a direction substantially parallel to the direction in which the clot 50 is pulled from the blood vessel (i.e., substantially parallel to the longitudinal axis 130 of the system). This limits the outward radial force applied to the blood vessel, meaning that the action of the thrombectomy device is not used to increase the force required to actually remove the clot from the blood vessel. This non-invasive feature is important for the typically fragile vessels of the neurovascular 40.

[0048] It is advantageous to deploy and retract the microcatheter 114 and thrombectomy device 118 from within the lumen 108 of the deployment catheter 106, so that the clot retrieval process remains isolated from and does not interfere with the stent implantation process. Similarly, thrombi can be aspirated and retrieved through the internal lumen of the deployment catheter without the need for the thrombectomy device.

[0049] In some cases, physicians may wish to reverse blood flow in the target vessel. Reversing the flow will prevent any embolism from migrating downstream within the vessel. Aspiration can be guided through the lumen 104 of the sheath member 102, the deployment catheter 106, or both. To isolate either catheter lumen for aspiration within the system, a seal can be formed between the inner and outer surfaces of the catheter. For example, if the aspiration source is connected to the lumen 104 at the proximal end of the guiding sheath 102, aspiration can be guided to the orifice at the distal end 107 of the deployment catheter 106 by utilizing the hydrogel seal between the outer surface 110 of the deployment catheter and the inner wall of the sheath member. In another example, an expandable member or frame can be used as a flow restriction between the surfaces. A low-pressure area can thus be diverted to the distal end 107 of the deployment catheter 106. In some cases, clots or fragments can be aspirated directly into the lumen 108 of the deployment catheter without the use of the microcatheter 114 and the thrombectomy device 118.

[0050] In another example, a thrombectomy and stent implantation system 100 for removing a clot from a neurovascular vessel 40 and implanting a stent may include a sheath member 102, a deployment catheter 106 disposed in a lumen 104 of the sheath member, a microcatheter 114 oriented in a lumen 108 of the deployment catheter, and a thrombectomy device 118 disposed in a lumen 116 of the microcatheter. The sheath member 102, the deployment catheter 106, and the microcatheter 114 may be substantially concentric and configured to move independently of each other along a longitudinal axis A1. Aspiration for the supported procedure may be directed to an orifice at the distal end 107 of the deployment catheter. The thrombectomy device may have an expandable frame configured to clamp and remove a strut or coronal portion of the occlusive clot 50.

[0051] The outer surface 110 of the deployment catheter 106 may also have a recessed region 120. The recessed region may have a first radial dimension D1, which is smaller than a second radial dimension D2 of another region of the outer surface adjacent to the recessed region. The deployment catheter 106 may have an inflatable stent implantation device 112 coupled to the outer surface 110 of the deployment catheter. The stent implantation device may be externally coupled to the recessed region 120 such that it is substantially radially flush with the outer surface 110. An inflation device 122 configured to inflate the stent implantation device 112 may also be included and coupled to the outer surface of the deployment catheter. In one example, the inflation device is a circumferential balloon that can be inflated with an imaging liquid medium. At least a portion of the stent implantation device 112 may be externally coupled to the inflation device 122.

[0052] Figure 2 A composite system 100 is shown that navigates to a target site within a neurovascular 40 via the internal carotid artery 30. The target site may be an occluded vessel, as shown, where an obstructive clot is lodged in an intracranial stenotic region in the form of a lesion 60 caused by the accumulation of atherosclerotic plaques. Figure 2 The system shown offers the advantage that the system's guiding catheter or sheath member 102 can act as a cannula protecting the system's internal components during navigation to the site. Due to the tortuous and varying diameters of the cerebral vascular system, other designs of balloon-inflatable coronary stents carry the risk of the stent being sheared off the balloon before reaching the target lesion. This is partly why considerable effort has been put into developing thin balloon catheters. The recessed or stepped segment 120, as described herein, allows for a more compact system 100 because it enables the use of a smaller diameter outer sheath member 102 while still protecting the system.

[0053] Figures 3A to 3J Cross-sectional views are shown, illustrating exemplary steps of one method of performing mechanical thrombectomy and subsequent stent implantation using the system of the present invention. When the system 100 is advanced to a position just proximal to the target lesion 60 and the occlusive clot 50, the deployment catheter 106 can be used as an aspiration catheter to aspirate the occlusion into the lumen 108 of the deployment catheter for removal. For more viscous and difficult-to-control occlusions, the microcatheter 114 can be advanced beyond the distal end 107 of the deployment catheter 106 and through the clot until the distal end 115 is located distal to the clot, as shown. Figure 3A As shown. A guidewire can also be used to position the microcatheter. In many cases, radiopaque markers or coils can be added to various parts of the device and / or catheter to help the user determine when the device is properly positioned on the clot. For example, a coil of radiopaque material such as tungsten and / or platinum can be attached to the distal end of the thrombectomy device to make the terminal easily visible during the treatment procedure. Once in place, the thrombectomy device 118 can be pulled out of its sheath as the microcatheter 114 is withdrawn proximally, allowing the thrombectomy device to expand within the clot 50 and reach either side of the clot, such as... Figure 3B As shown. The support of the capture section of the device expands to clamp the clot.

[0054] Once the user is satisfied that the thrombectomy device 118 has firmly clamped the clot 50, the device can be withdrawn proximally back into the deployment catheter 106, as... Figure 3C As shown. This can be accomplished by aspiration via the deployment of catheter 106 to help maintain a firm grip on the clot and prevent fragment loss and migration. If necessary, the user can completely remove the thrombectomy device and microcatheter from system 100 and the patient to allow for more effective aspiration during subsequent steps. Multiple passes of the microcatheter and thrombectomy device may also be necessary to adequately clear the vessel.

[0055] After the occlusive clot is securely secured and removed, the remainder of the system 100 within the sheath member 102 can be advanced through the stenosis, aligning the stent implantation device 112 and the inflation device 122 with the lesion 60, as... Figure 3D As shown. Good alignment ensures that the radial forces applied to the blood vessel during stent implantation are distributed as evenly as possible along the longitudinal length of the device. Figure 3B Similar to thrombectomy, proper alignment can be achieved by placing radiopaque markers or coatings. Once aligned across the entire lesion, the sheath member 102 can be retracted, allowing the distal end 109 of the sheath to return to the proximal side of the stenosis, exposing the stent implantation device 112, as... Figure 3E As shown.

[0056] Once exposed, the stent implantation device 112 can self-inflate or radially expand via the inflation device 122. The inflatable component of the inflation device 122 can be filled with a working fluid, typically a contrast agent, via an inflation lumen or tube 124. Once inflation begins, the inflation device allows the stent implantation device 112 to expand radially, such as... Figure 3F As shown, as the inner diameter of the target blood vessel is constricted by the stenosis, the outer surface of the stent implantation device can first contact the plaque or fatty deposits in the lesion 60. Figure 3G This illustrates that as the outer diameter of the stent implantation device continues to increase, this contact can gently apply radial compression to the lesion by squeezing it between the stent implantation device and the vessel wall. Once the lesion can no longer be compressed further, continued inflation can expand and enlarge the lumen diameter until the desired implant diameter D3 of the vessel is reached, such as... Figure 3H As shown. In one example, the desired diameter is reached when the first diameter of the constricted portion of the blood vessel containing the lesion increases to 75% of the second diameter of the portion of the blood vessel adjacent to the first diameter.

[0057] In an alternative step, the stent implantation device 112 may be a self-expanding structure configured to present a predetermined outer diameter upon deployment without requiring an inflation device 122. The outer diameter of the device may be selected such that the required radial force is applied to the blood vessel and the implant diameter D3 is sufficient to allow flow recanalization.

[0058] After the occluded neurovascular 40 is reopened by inflation, the stent implantation device 112 can be left in place as an implanted stent by deflating the inflation device 122. This can be achieved by attaching an aspiration source to the proximal end of the inflation tube 126. Aspiration may continue until the inflation device contracts to a diameter close to the diameter D2 of the outer surface 110 of the deployment catheter 106. Alternatively, aspiration may continue until the inflation device contracts to a diameter smaller than the inner diameter of the sheath member 102, thereby allowing the deployment catheter to retract into the lumen 104 of the sheath member 102, such as... Figure 3I and Figure 3JAs shown, the inflatable stent implantation device 112 is no longer pinned by the inflation device, but is held in place as a stent to ensure the patency of the target blood vessel lumen.

[0059] Figure 4 This is a flowchart illustrating methodological steps involving endovascular treatments such as thrombectomy and stent implantation using systems such as those described herein. See also Figure 4 The method 400 outlined herein, in step 410, provides access to a patient's blood vessel using conventionally known techniques, and the three-catheter system is positioned near the lesion and occlusive clot in the occluded neurovascular vessel. The first catheter may be a guiding catheter or sheath component as described herein or originally known to those skilled in the art. The second catheter may be a delivery catheter having an inflation device and stent implantation device as described herein. The delivery catheter may also be configured as an aspiration catheter. The third catheter may be a microcatheter having a lumen and thrombectomy device as described herein or originally known to those skilled in the art.

[0060] In step 420, the distal portion of the microcatheter and thrombectomy device is advanced from the deployment catheter toward and through the occlusive clot in the neurovascular bundle, while keeping the deployment catheter, inflation device, stent implantation device, and sheath close to the lesion. In step 430, the thrombectomy device is deployed to capture the occlusive clot, as shown and described herein, or by other means that will be understood by those skilled in the art, such as direct aspiration. Step 430 may also include the step of retracting the captured clot, thrombectomy device, and microcatheter proximally into the lumen of the deployment catheter. At this stage, if desired by the user, the captured clot, thrombectomy device, and microcatheter can be completely removed from the system and the patient.

[0061] In step 440, the sheath component, deployment catheter, inflation device, and stent implantation device are advanced distally through the lesion. The stent implantation device may be aligned with the lesion. In step 450, the sheath component is retracted proximally to the lesion to expose the stent implantation device and allow it to expand.

[0062] In step 460, the inflation device is inflated to expand the stent implantation device, thereby dilating the lesion and increasing the diameter of the blood vessel lumen. The stent implantation device may expand until the desired stent implant diameter is achieved. In step 470, the inflation device is deflated to release pressure on the implanted stent implantation device and allow the deployment catheter to be withdrawn into the sheath member. In step 480, the stent remains in the blood vessel as an implant. Step 480 may also include a step of removing the remainder of the system from the patient.

[0063] The invention is not necessarily limited to the described examples, the configurations and details of which may vary. The terms “distal” and “proximal” are used throughout the foregoing description and refer to position and orientation relative to the treating physician. Similarly, “distal” or “towards distal” refers to a position away from the physician or in a direction away from the physician. Likewise, “proximal” or “towards proximal” refers to a position close to the physician or in a direction toward the physician. Furthermore, unless the context clearly indicates otherwise, the singular forms “an,” “a,” and “the / described” include plural references.

[0064] "Comprising," "containing," or "including" means that at least the named compound, element, particle, or method step is present in the composition, article, or method, but does not exclude the presence of other compounds, materials, particles, or method steps, even if the other such compounds, materials, particles, or method steps have the same function as the named ones.

[0065] In describing the example embodiments, terminology is used for clarity. It is intended that each term be contemplated for its broadest meaning as understood by one skilled in the art, and includes all technical equivalents that operate in a similar manner to achieve a similar purpose. It should also be understood that reference to one or more steps of a method does not exclude the presence of additional method steps or intermediate method steps between those explicitly identified steps. Some steps of the method may be performed in an order different from that described herein without departing from the scope of the disclosed art. Similarly, it should be understood that reference to one or more components in an apparatus or system does not exclude the presence of additional components or intermediate components between those explicitly identified components. For clarity and brevity, not all possible combinations are listed.

[0066] As used herein, the term “about” or “approximately” for any numerical value or range indicates a suitable dimensional tolerance that allows a collection of parts or components to achieve the intended purpose as described herein. More specifically, “about” or “approximately” may refer to a range of ±20% of the enumerated values, for example, “about 90%” may refer to a range of values ​​from 71% to 99%.

[0067] The description contained herein is an example of embodiments of the invention and is not intended to limit the scope of the invention in any way. While specific examples of the invention have been described, various modifications may be made to the apparatus and methods without departing from the scope and spirit of the invention. For example, while the examples described herein relate to specific components, the invention includes other examples such as using various combinations of components to achieve the function, using alternative materials to achieve the function, combining components of the various examples, combining components of the various examples with known components, etc. The invention contemplates replacing the components shown herein with other well-known and commercially available products. These modifications will generally be apparent to those skilled in the art to which this invention pertains and are intended to fall within the scope of the following claims.

Claims

1. A thrombectomy and stent implantation system for removing a clot from a blood vessel and implanting a stent into the blood vessel, the system comprising: A sheath component, the sheath component including a sheath lumen; A deployment catheter, the deployment catheter being oriented within the sheath lumen, the deployment catheter comprising a deployment catheter lumen and a deployment catheter outer surface; A stent implantation device, wherein the stent implantation device is externally connected to the outer surface of the deployment catheter, and wherein the stent implantation device includes a stent; A microcatheter oriented in a deployment catheter lumen, wherein the microcatheter includes a microcatheter lumen; as well as A thrombectomy device, wherein at least a portion of the thrombectomy device is oriented within the lumen of the microcatheter; The thrombectomy device includes an expandable clot retrieval device that is collapsible to fit within the microcatheter lumen and self-expanding upon exiting the microcatheter lumen; and wherein The clot retrieval device includes a clot engagement portion, the clot engagement portion including an expandable network of struts configured to hold the clot and remove the clot from the blood vessel; The thrombectomy device is retracted into the deployment catheter before the stent is deployed near the lesion.

2. The system of claim 1, wherein the deployment conduit further comprises: Deploy the outer diameter of the catheter; as well as A recessed region located on the outer surface of the deployment conduit and near the distal end of the deployment conduit, the recessed region including an outer diameter of the recessed region configured to be smaller than the outer diameter of the deployment conduit.

3. The system of claim 2, wherein the stent implantation device is externally connected to the recessed area of ​​the deployment catheter.

4. The system according to claim 1, further comprising: An inflation device is connected to the outer surface of the deployment conduit. A portion of the stent implantation device is externally connected to the inflation device, and The inflation device is configured to expand the stent implantation device.

5. The system of claim 1, wherein the sheath lumen, the deployment catheter lumen, and the microcatheter lumen are substantially concentric.

6. The system of claim 1, wherein the deployment catheter includes a flexible portion adjacent to the stent implantation device.

7. A thrombectomy and stent implantation system for removing a clot from a blood vessel and implanting a stent into the blood vessel, the system comprising: A sheath component, the sheath component including a sheath lumen; A deployment catheter, the deployment catheter being oriented within the sheath lumen, the deployment catheter comprising a deployment catheter lumen and a deployment catheter outer surface; A stent implantation device, the stent implantation device being coupled to the outer surface of the deployment catheter, wherein the stent implantation device includes a stent; A microcatheter oriented in a deployment catheter lumen, wherein the microcatheter includes a microcatheter lumen; as well as A thrombectomy device, wherein at least a portion of the thrombectomy device is oriented within the lumen of the microcatheter; The sheath member, the deployment catheter, and the microcatheter are substantially concentric and configured to move independently of each other along an axis; The thrombectomy device includes an expandable clot retrieval device that is collapsible to fit within the microcatheter lumen and self-expanding upon exiting the microcatheter lumen; and wherein The clot retrieval device includes a clot engagement portion, the clot engagement portion including an expandable network of struts configured to hold the clot and remove the clot from the blood vessel; The thrombectomy device is retracted into the deployment catheter before the stent is deployed near the lesion.

8. The system of claim 7, wherein the deployment conduit further includes a recessed region on the outer surface of the deployment conduit, wherein the recessed region comprises a size smaller than the size of another region on the outer surface of the deployment conduit adjacent to the recessed region.

9. The system of claim 8, wherein the stent implantation device is externally connected to the recessed region of the deployment catheter.

10. The system according to claim 7, further comprising: An inflation device is connected to the outer surface of the deployment conduit. A portion of the stent implantation device is externally connected to the inflation device.

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