Single integrated intravascular device

Abstract

The present invention is entitled "Single integrated intravascular device". A single integrated intravascular device, the single integrated intravascular device comprising a stent retriever and a semi-compliant balloon accommodated in the stent retriever. After traversing the clot, the device is deployed to a self-expanding state so as to engage the clot therein, whereby the device together with the embedded clot is removed. By imaging to detect the stenosis at the initial position of the captured clot, the device is reintroduced to that position and the stent retriever is deployed to a self-expanding state. Inflating the semi-compliant balloon expands the stent retriever to a super-expanded state greater than the self-expanding state, thereby dilating the blood vessel while completely separating / releasing the stent retriever from the remaining part of the device. Then, the semi-compliant balloon together with the remaining part of the device collapses and is withdrawn while the separable / releasable part of the stent retriever in the self-expanding state remains in the blood vessel.

Description

Background Art Technical Field

[0002] The present invention relates to intravascular devices. Specifically, the present invention relates to an improved single integrated intravascular device that includes a stent retriever and a balloon, thereby providing multi-functional treatment including clot removal, angioplasty, and / or restenosis prevention using a single device.

[0003] Related Art

[0004] Mechanical thrombectomy devices (e.g., stent retrievers or stent thrombectomy devices) are commonly used to remove clots, thrombi, obstructions, or blockages that impede blood flow in arteries. Using standard imaging techniques (e.g., X-ray radiology), a guide wire can be advanced alone across and beyond the target clot, thrombus, obstruction, or blockage through the artery, and then a microcatheter is tracked over the guide wire. Alternatively, the microcatheter together with a guide wire disposed within the lumen of the microcatheter can be advanced across the target clot as a single unit through the artery. In either case, with the microcatheter in place at the target site, the guide wire is withdrawn proximally, and a mechanical thrombectomy device (e.g., a stent retriever or stent thrombectomy device) is advanced through the lumen of the microcatheter such that the stent thrombectomy device straddles (crosses) the target clot. Now, the microcatheter is withdrawn proximally, thereby deploying (i.e., disengaging) the mechanical thrombectomy device that coincides with the obstructing mass. The mechanical thrombectomy device is no longer radially constrained by the microcatheter but automatically radially self-expands to an enlarged maximum diameter. When the stent thrombectomy device self-expands to engage the thrombus therein, the stent thrombectomy device exerts a radial force that compresses the thrombus against the vessel wall, thereby immediately restoring partial reperfusion of the distal vasculature. After a predetermined period of time (e.g., about 2 minutes - 5 minutes), the thrombus is sufficiently embedded in the spaces or openings between the struts of the expanded stent thrombectomy device. The microcatheter and the mechanical thrombectomy device that capture, embed, or engage the clot are withdrawn from the body as a single unit.

[0005] Sometimes, a potential stenosis (i.e., narrowing of the artery due to plaque accumulation) present behind the clot is initially undetected and only becomes apparent to the interventional physician after the thrombus itself has been removed. In such cases, to restore blood flow in the artery, a separate angioplasty procedure is performed using a separate device (e.g., a balloon catheter). Once the catheter has been advanced to coincide with the stenotic opening of the vessel, the balloon disposed at the end of the catheter is inflated. When the balloon expands, it radially outwardly pushes the plaque against the inner wall of the vessel, thereby restoring blood flow through the vessel. If necessary, in a third procedure separate from clot removal and opening the stenotic vessel, a mesh stent separate from the stent thrombectomy device and the balloon catheter can be deployed and permanently implanted in the body to maintain patency.

[0006] Accordingly, there is a desire to develop a simplified multi-functional treatment method to perform clot capture, angioplasty, and / or restenosis prevention using a single integrated intravascular device including a stent retriever and a semi-compliant balloon, thereby eliminating the need to perform separate medical procedures using separate devices. SUMMARY OF THE INVENTION

[0007] One aspect of the present invention relates to performing clot capture, angioplasty, and / or restenosis prevention using a single integrated intravascular device including a self-expanding stent retriever and a semi-compliant balloon, thereby eliminating the need to perform separate medical procedures using separate devices.

[0008] Another aspect of the present invention relates to a single integrated intravascular device including: a pusher member having a proximal end and an opposite distal end; and a self-expanding stent retriever including an open stent formed by a plurality of struts fixed together. The self-expanding stent retriever is capable of transitioning between a compressed state with a reduced diameter and a self-expanding state with an increased diameter when the externally applied mechanical force imposed by a microcatheter is withdrawn. The proximal end and the distal end of the self-expanding stent retriever are fixed to the pusher member at respective proximal and distal fixation points, and the self-expanding stent retriever is separable or releasable from the pusher member at the respective proximal and distal fixation points. The device further includes a semi-compliant balloon received within the self-expanding stent retriever and fixed to the pusher member axially extending through the semi-compliant balloon; and an inflation lumen axially defined within the pusher member and in fluid communication with the semi-compliant balloon.

[0009] Another aspect of the present invention relates to a method for using the single integrated intravascular device as described in the preceding paragraph. The method includes the steps of advancing a guide wire and a microcatheter across a target clot into a blood vessel. Then, the guide wire is withdrawn proximally while the microcatheter is maintained in a position across the target clot within the blood vessel. The single integrated intravascular device is loaded into the lumen of the microcatheter when the self-expanding stent retriever is in the compressed state and the semi-compliant balloon in the deflated state is received therein. Then, the single integrated intravascular device is advanced through the lumen of the microcatheter using the pusher member such that the self-expanding stent retriever coincides with the target clot. At this time, the microcatheter is withdrawn proximally from the blood vessel while the single integrated intravascular device is maintained across the target clot within the blood vessel. When deployed from the microcatheter, the self-expanding stent retriever automatically transitions to the self-expanding state, thereby engaging the target clot within the open stent of the self-expanding stent retriever while the semi-compliant balloon received within the self-expanding stent retriever remains in the deflated state so as not to interfere with the engagement and subsequent entrapment of the target clot within the self-expanding stent retriever.

[0010] Another aspect of the present invention relates to a method for using a single integrated intravascular device that includes a stent retriever and a semi-compliant balloon housed within the stent retriever. First, the single integrated intravascular device is introduced into a blood vessel to traverse a target clot. Then, the stent retriever is deployed to a self-expanding state, and the target clot is embedded therein. The single integrated intravascular device having the embedded clot therein is removed from the blood vessel. By imaging, a potential residual stenosis in the blood vessel is detected at the initial location of the captured target clot. Thereby, the single integrated intravascular device is reintroduced into the blood vessel to a position where the stent retriever coincides with the detected potential residual stenosis. Similarly, the stent retriever is deployed such that the stent retriever transitions from a compressed state to a self-expanding state. Next, the semi-compliant balloon is inflated with an inflation medium to expand the stent retriever to a super-expanded state having a diameter greater than the self-expanding state, thereby dilating the blood vessel at the location of the detected potential residual stenosis while completely separating or releasing the stent retriever from the remainder of the single integrated intravascular device. Now, the semi-compliant balloon is collapsed by removing the inflation medium therefrom. Finally, the remainder of the single integrated intravascular device is withdrawn proximally from the blood vessel while the separable or releasable portion of the stent retriever in the self-expanding state is maintained within the blood vessel at the location of the detected potential residual stenosis. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] The above and other features of the present invention will become more apparent from the following detailed description and the accompanying drawings, in which like reference numerals throughout several views refer to like elements, and in which:

[0012] Figure 1 is a cross-sectional view of an exemplary single integrated intravascular device according to the present invention that includes a self-expanding stent retriever and a semi-compliant balloon;

[0013] Figure 2A shows a guide wire and a microcatheter positioned to straddle a target clot in a blood vessel;

[0014] Figure 2B shows after the guide wire has been withdrawn proximally from the blood vessel Figure 1 the single integrated intravascular device of the present invention being advanced through the lumen of the microcatheter such that the self-expanding stent retriever traverses the target clot in the blood vessel;

[0015] Figure 2C shows after the microcatheter has been withdrawn proximally from the blood vessel, the self-expanding stent retriever being deployed and automatically expanding to a radially self-expanding state, thereby engaging the target clot within the open spaces of the stent;

[0016] Figure 2DShows a self-expanding stent retriever in a radially self-expanding state, with the clot embedded therein withdrawn proximally into a larger-diameter proximal catheter;

[0017] Figure 2E Shows the presence of potential residual stenosis at the initial site in the blood vessel of the target clot, and the guide wire and microcatheter are reintroduced into the blood vessel simultaneously or successively to reach a position coinciding with the potential residual stenosis;

[0018] Figure 2F Shows that after the guide wire is withdrawn proximally from the blood vessel, Figure 1 the single integrated intravascular device of the present invention is reloaded into the lumen of the microcatheter such that the self-expanding stent retriever coincides with the potential residual stenosis;

[0019] Figure 2G Shows that after the microcatheter is withdrawn proximally from the blood vessel, the self-expanding stent retriever is deployed and automatically deployed to a radially self-expanding state at the detected position of the potential residual stenosis;

[0020] Figure 2H Shows the inflation of a semi-compliant balloon housed within the self-expanding stent retriever to dilate the blood vessel at the detected potential residual stenosis; the self-expanding stent retriever is shown in a super-expanded state with a diameter greater than that in the Figure 2G self-expanding state;

[0021] Figure 2I Shows that after the fragile segments of the stent of the self-expanding stent retriever break when deformed by the inflated semi-compliant balloon and then the semi-compliant balloon is deflated, the remaining portion of the self-expanding stent retriever is withdrawn proximally from the blood vessel as a single unit, which remains fixed to the pusher shaft together with the deflated balloon, while the detachable portion of the self-expanding stent retriever in the self-expanding state remains permanently in place within the blood vessel to prevent restenosis;

[0022] Figure 2J For Figure 2H an enlarged area of cross-section II(J) of the struts of the self-expanding stent retriever in, the struts having a thinner cross-section to facilitate breakage when the semi-compliant balloon is inflated, thereby causing the self-expanding stent retriever to transition to the super-expanded state;

[0023] Figure 3A Is a cross-sectional view of an alternative configuration of the single integrated intravascular device of the present invention including a self-expanding stent retriever and a semi-compliant balloon; wherein the distal end and proximal end of the self-expanding stent retriever are releasably fixed to the pusher member via respective distal and proximal sleeves;

[0024] Figure 3B For Figure 3ACross-sectional view of a single integrated intravascular device after a self-expanding stent retriever has been deployed from a microcatheter and transitioned to a self-expanded state;

[0025] Figure 3C For Figure 3A Cross-sectional view of a single integrated intravascular device, where a semi-compliant balloon has been inflated, causing the self-expanding stent retriever to radially expand to an over-expanded state (the diameter in the over-expanded state is larger than the self-expanded state in Figure 3B ), while the corresponding proximal and distal ends of the self-expanding stent retriever are axially shortened; and

[0026] Figure 3D For Figure 3A Cross-sectional view of a single integrated intravascular device, where the proximal and distal ends of the self-expanding stent retriever are released or disengaged from the corresponding proximal and distal sleeves, allowing the released self-expanding stent retriever to return to its preformed shape. Detailed Description

[0027] The terms "distal" or "proximal" are used in the following description with respect to the position or direction relative to the treating physician or medical interventionist. "Distal" or "distally" is a position away from the physician or interventionist or in the direction away from the physician or interventionist. "Proximal" or "proximally" or "proximal" is a position close to the physician or medical interventionist or in the direction towards the physician or medical interventionist. The terms "occlusion", "clot", thrombus or "blockage" may be used interchangeably.

[0028] The present invention relates to a single integrated intravascular device comprising a self-expanding stent retriever and a semi-compliant balloon. The term "semi-compliant balloon" is defined herein as a balloon that expands its diameter by approximately 10% between the nominal pressure (pressure at the marked diameter) and the rated burst pressure (at 95% confidence, 99.9% will not fail at or below the rated burst). Exemplary semi-compliant balloon materials include, but are not limited to, polyethylene, polyolefin copolymers or polyamides (nylon). Heretofore, multiple intravascular treatments (clot removal; angioplasty; restenosis prevention) have been performed successively, one after another, each treatment using a different separate device dedicated to one treatment or procedure. With the single integrated intravascular device of the present invention, multiple intravascular treatments or procedures can now be performed in a single simplified procedure, thus saving time, reducing device exchanges and providing flexibility to the interventionist to permanently deploy a stent at any point in the thrombectomy procedure. The single integrated intravascular device can be used to perform multiple intravascular treatments or procedures, including clot capture / removal, angioplasty and / or restenosis prevention.

[0029] See Figure 1, a single integrated intravascular device 100 of the present invention includes a mechanical thrombectomy device (e.g., a self-expanding stent retriever) 115, which includes an open mesh formed by a plurality of struts, a cage, a stent, or a framework, and these struts are connected together with a space or opening 116 defined therebetween, through which a clot can engage, be captured, and become embedded over time. The self-expanding stent retriever 115 is made of an automatically self-expanding material (e.g., a biocompatible superelastic shape memory material such as nitinol (e.g., nickel-titanium)), which can be curled downward or reduced in diameter to a compressed state capable of being received within the lumen of a microcatheter, as described in further detail below. The deflated semi-compliant balloon 120 is housed within the self-expanding stent retriever 115. The proximal and distal ends of each of the semi-compliant balloon 120 and the self-expanding stent retriever 115 are fixed (e.g., fused) to the proximal shaft or pusher member 125 at corresponding proximal fixation points 117 and distal fixation points 117'. As Figure 1 shown, the proximal segment of the pusher member 125 extends proximally and axially completely through the semi-compliant balloon 120, while the distal segment of the pusher member 125 extends outwardly beyond the distal end of the semi-compliant balloon 120 and the self-expanding stent retriever 115. The stiffness of the pusher member 125 preferably varies along its axial length from a rigid proximal end to a more flexible distal end that axially extends beyond the semi-compliant balloon and the self-expanding stent retriever. The inflation / deflation lumen 127 is defined axially through a portion of the proximal segment of the pusher member 125 and is in fluid communication with the semi-compliant balloon 120, and this inflation / deflation lumen receives an inflation medium (e.g., a 50% contrast agent saline solution) for inflating / deflating the semi-compliant balloon 120. As is Figure 1 apparent from the illustration, the inflation / deflation lumen 127 is in fluid communication with the semi-compliant balloon without axially extending beyond the semi-compliant balloon into the distal segment of the pusher member 125.

[0030] To date, multi-functional endovascular medical procedures (i.e., clot capture / retrieval; angioplasty; and subsequent implantation of a permanent stent to prevent restenosis) have required the use of different individual medical devices in successive medical treatments. The use of a single integrated endovascular device of the present invention has simplified these individual medical treatments. An overall overview of the multi-functional applications of the single integrated endovascular device of the present invention is provided, and the specific details of operating the device will be shown in the following description. Initially, the self-expanding stent retriever component of the single integrated endovascular device of the present invention can be used to capture a target clot and withdraw the target clot into the proximal catheter. Then, imaging can be performed to determine whether there is a potential residual stenosis at the initial site of the target clot. If the presence of a potential residual stenosis is detected at the initial site of the target clot, the same single integrated endovascular device 100 can be reloaded into the microcatheter and reintroduced back to the initial site of the target clot where the potential residual stenosis has been detected. At this initial site of the blood vessel, angioplasty can be performed on the potential residual stenosis by inflating a semi-compliant balloon housed within the self-expanding stent retriever to dilate the opening of the artery to restore blood flow therethrough. As the semi-compliant balloon inflates, the self-expanding stent retriever can be separated or released (disengaged) from the remaining portion of the single integrated endovascular device. Then, the remaining portion of the single integrated endovascular device can be withdrawn, leaving in the blood vessel the separated or released (disengaged) portion of the self-expanding stent retriever in a self-expanded state to prevent elastic vessel recoil or restenosis.

[0031] The use of the single integrated endovascular device is described in detail below. Since the single integrated endovascular device of the present invention employs a semi-compliant balloon, the single integrated device is prepared by removing, purging, or evacuating residual air from the device before introducing the single integrated device into the body. Removal of the residual air can be achieved by applying a vacuum using a syringe 110 or other mechanical device connected to the proximal hub 105. Figure 1 The exemplary illustration in shows a single inflation / deflation lumen 127, however, it is contemplated and within the scope of the present invention that separate inflation and deflation lumens (coaxial or side-by-side arrangement) may be employed as needed.

[0032] Once prepared, the use of the single integrated device 100 of the present invention begins by introducing a guide wire 200 into the artery 205 and advancing the guide wire across the target clot, thrombus, occlusion, or blockage 210, as Figure 2A shown. Then, a microcatheter 220 having a lumen 225 axially defined therein is tracked over the guide wire 200 until the distal end 230 of the microcatheter 220 crosses the target clot 210 and extends distally beyond the target clot 210. Then the guide wire 200 is withdrawn proximally from the blood vessel while maintaining the microcatheter 220 in a position across the target clot 210 in the blood vessel 205. SeeFigure 2B When the self-expanding stent retriever 115 is in a compressed state (e.g., wrapped by a microcatheter so as to be curled downwardly with a reduced diameter) and the deflated semi-compliant balloon 120 is accommodated therein, the single integrated intravascular device 100 is introduced into the lumen 225 of the microcatheter 220. Under the guidance of imaging, the single integrated intravascular device 100 is advanced through the lumen 225 of the microcatheter 220 using the pusher member 125 such that the self-expanding stent retriever 115 traverses the target clot 210. See Figure 2C , then the microcatheter 220 is retracted or withdrawn proximally while the single integrated intravascular device 100 remains in place across / straddling the target clot 210 within the blood vessel 205. As the microcatheter 220 is retracted proximally from the blood vessel 205, the microcatheter 220 unfolds or disengages the self-expanding stent retriever 115 disposed therein, and the self-expanding stent retriever automatically transitions to a self-expanded state with an enlarged diameter, thereby engaging the target clot 210 within the open spaces 116 of the mesh or stent structure. While the stent or framework structure of the self-expanding stent retriever 115 expands radially outwardly, the semi-compliant balloon 120 accommodated therein remains in a deflated state so as not to impede the engagement and subsequent entrapment of the target clot 210. Over time (e.g., about 2 minutes - 5 minutes), the target clot 210 is sufficiently entrapped within the interstices or openings 116 of the stent of the self-expanding stent retriever 115. Then, the target clot 210 entrapped in the self-expanding stent retriever 115 together with the deflated semi-compliant balloon 120 accommodated therein is withdrawn proximally as a single unit and received in the proximal catheter 235, the diameter of which is large enough to accommodate the self-expanding stent retriever 115 (which is in a self-expanded state) without compressing and stripping the target clot, as Figure 2D shown.

[0033] The function of the single integrated intravascular device of the present invention does not necessarily end here. Now that the self-expanding stent retriever 115 and the target clot 210 captured therein have been received in the proximal catheter 235 and withdrawn from the blood vessel 205, it can be detected by imaging whether there is any potential residual stenosis 215 at the initial location of the captured target clot.

[0034] If a residual stenosis 215 is detected during imaging, the single integrated intravascular device 100 can be cleaned and reloaded into the microcatheter 220. Similar to the situation in Figure 2A (but the target clot 210 has been captured and removed from the blood vessel), the guide wire 200 and the microcatheter 220 are reintroduced successively (one after another) or simultaneously and tracked through the blood vessel 205 to the detected potential residual stenosis 215, as Figure 2EAs shown. Then, the guide wire 200 is withdrawn proximally from the blood vessel, leaving the microcatheter 220 in a position coinciding with the potential residual stenosis 215. While the self-expanding stent retriever 115 is in a compressed state (i.e., curled downward to have a reduced diameter) and the deflated semi-compliant balloon 120 is accommodated therein, the single integrated intravascular device 100 is reloaded into the microcatheter 220 and advanced such that the self-expanding stent retriever 115 coincides with the potential residual stenosis 215, as Figure 2F shown. Referring Figure 2G to, the microcatheter 220 is withdrawn proximally from the blood vessel 205, thereby deploying the self-expanding stent retriever 115 and allowing it to automatically expand radially to a self-expanded state. With the self-expanding stent retriever 115 in a self-expanded state, the syringe 110 distributes inflation medium under pressure through the inflation lumen 127 of the pusher member 125 that fills the semi-compliant balloon 120. The self-expanding stent retriever 115 can be configured such that certain portions of the stent or struts include weakened segments or frangible segments 111 disposed at a plurality of strut positions near the proximal and distal fixation points of the pusher member 125. The frangible segments 111 of the self-expanding stent retriever can be designed as strut segments having a thinner cross-section (as Figure 2J shown), or can be designed as struts having a local stress gradient (notch).

[0035] When the semi-compliant balloon 120 is inflated to apply a radially outward force, the self-expanding stent retriever 115 is over-expanded to a diameter greater than the self-expanded state while adopting the curved profile of the inflated semi-compliant balloon, as Figure 2H shown. The inflated balloon enlarges or dilates the stenotic opening in the blood vessel where plaque accumulation is present, thereby improving blood flow therethrough.

[0036] At some point during the inflation of the semi-compliant balloon 120, a sufficient radially outward force is imposed to deform the frangible segments 111 of the self-expanding stent retriever 115, resulting in the fracture or rupture of the frangible segments 111. The fracture of the frangible segments 111 causes the separable portion 130' of the self-expanding stent retriever 115 to completely disengage or release from the remaining portion 130 of the self-expanding stent retriever 115 that remains fixed to the pusher member 125 at the corresponding proximal and distal fixation points. Negative pressure is applied using the syringe 110, which discharges the inflation medium via the inflation / deflation lumen 127 of the pusher member 125 such that the collapsed semi-compliant balloon 120 can be withdrawn from the blood vessel. When the semi-compliant balloon 120 collapses, the separable portion 130' of the self-expanding stent retriever transitions from the over-expanded state ( Figure 2H ) to the self-expanded state of a smaller diameter ( Figure 2I ). Figure 2IAlso shown is the severed separable portion 130' of a self-expanding stent retriever maintained in the self-expanded state within the blood vessel 205, while the remaining portion 130 fixed to the pusher member 125, together with the deflated semi-compliant balloon 120, is withdrawn proximally from the blood vessel as a single unit. The separable portion 130' of the self-expanding stent retriever 115 in the self-expanded state is permanently retained within the blood vessel at the location where residual stenosis is detected to prevent restenosis. Thus, restenosis (re-narrowing of the arterial opening), which typically occurs within about 6 months - 12 months after the blood vessel opening is dilated by an inflated balloon, is prevented or reduced by permanently retaining the separable portion of the self-expanding stent retriever in place within the blood vessel.

[0037] Instead of designing the struts of the self-expanding stent retriever to have frangible segments 111 that break or fracture upon deformation, the self-expanding stent retriever can alternatively be releasably fixed to the pusher member. By way of an illustrative example, Figure 3A an alternative configuration is shown where a self-expanding stent retriever 315 (when in the coiled state) having a deflated semi-compliant balloon 320 therein is advanced through a microcatheter 370 to a target site within the blood vessel. The proximal end struts and distal end struts of the self-expanding stent retriever 315 are respectively fixed to the pusher member 325 via a proximal sleeve or end cap 385 and a distal sleeve or end cap 385' that are axially held in place relative to each other. When the microcatheter 370 is withdrawn proximally, the self-expanding stent retriever 315, no longer constrained by the microcatheter, automatically self-expands, thereby increasing in diameter to the self-expanded state, as Figure 3B shown. Despite such expansion, the distal end struts and proximal end struts of the self-expanding stent retriever 315 remain constrained or fixed by the proximal sleeve 385 and the distal sleeve 385'. Thus, the self-expanding stent retriever 315, when in the self-expanded state, can engage and remove the target clot similar to the self-expanding stent retriever described above with respect to Figures 2A to 2J If, after removing the target clot, stenosis is detected by imaging at the site of the removed target clot, the device can be cleaned again in accordance with the description and procedure of the design regarding Figures 2A to 2J above, and then reloaded into the blood vessel to the target site. Once the self-expanding stent retriever is positioned at the target site, the microcatheter 370 is withdrawn proximally. The deployment of the downwardly coiled self-expanding stent retriever 315 causes its diameter to increase to the self-expanded state, yet the distal end struts and proximal end struts of the self-expanding stent retriever remain fixed to the pusher member 325 below the respective proximal sleeve 385 and distal sleeve 385'. See Figure 3C, the semi-compliant balloon 320 is inflated, causing the self-expanding stent retriever 315 to transition to a super-expanded state (i.e., a diameter greater than the self-expanded state diameter when the self-expanding stent retriever is not covered by the microcatheter but remains fixed by the proximal sleeve 385 and the distal sleeve 385', as Figure 3B shown). The semi-compliant balloon 320 is inflated to a super-expanded state, increasing the diameter (in the direction transverse to the axial direction - as indicated by the larger arrow), which in turn causes the self-expanding stent retriever (axial direction - as indicated by the smaller arrows drawn towards each other) to shorten to such an extent that the distal end struts and proximal end struts of the self-expanding stent retriever disengage or separate from the proximal sleeve 385 and the distal sleeve 385' (no longer fixed by the proximal sleeve 385 and the distal sleeve 385'). Once released or separated from the proximal and distal sleeves (as Figure 3D shown), the diameters of the distal end struts and proximal end struts of the self-expanding stent retriever automatically expand to their preformed shape, thus making direct physical contact with the inner wall of the blood vessel at the narrow target site. Thereafter, the semi-compliant balloon 320 can be deflated and removed proximally together with the sleeves 385, 385' and the pusher member 325, while the separated (disengaged) self-expanding stent retriever 315 remains in permanent physical contact with the inner wall of the blood vessel 305 at the target site.

[0038] Regardless of the specific design or construction of the device, if the self-expanding stent retriever is substantially "waist constricted", indicating that it cannot be embedded in the target clot and there may be a potential stenosis, the step of removing the target clot can be completely bypassed. In such a case, the interventional physician can directly proceed to inflate the semi-compliant balloon, causing the self-expanding stent retriever to transition to a super-expanded state and separate / release itself from the pusher member without attempting to remove or withdraw the clot. After deflation, the semi-compliant balloon is withdrawn together with the pusher member, thereby placing the separated / released self-expanding stent retriever in a position of physical contact with the blood vessel wall at the stenotic site in the self-expanded state.

[0039] Thus, the single integrated intravascular device of the present invention is used to perform multi-functional treatments, including: (i) capturing and removing a target clot; (ii) dilating a stenotic opening of a blood vessel, where a potential residual stenosis is detected below the target clot after removal; and / or (iii) permanently holding a separable / releasable (disengaged) self-expanding stent retriever at the detected potential residual stenosis position in the blood vessel to prevent restenosis.

[0040] Accordingly, while the fundamental novel features of the invention which are applied to its preferred embodiments have been shown, described, and pointed out, it should be understood that various omissions, substitutions, and changes in form and detail may be made by those skilled in the art without departing from the spirit and scope of the invention. For example, all combinations of elements and / or steps which perform substantially the same function in substantially the same way to achieve the same result are clearly contemplated as being within the scope of the invention. Substitutions of elements from one described embodiment to another are also fully contemplated and envisioned. It should also be understood that the drawings are not necessarily drawn to scale, but are in essence merely conceptual. Accordingly, the only intention is to be limited as indicated by the scope of the appended claims.

[0041] Each published patent, pending patent application, publication, journal article, book, or any other reference cited herein is hereby incorporated by reference in its entirety.

Claims

1. A single integrated intravascular device, comprising: A pusher member having a proximal end and an opposite distal end; A self-expanding stent retriever including an open stent formed by a plurality of struts fixed together; the self-expanding stent retriever is capable of transitioning between a compressed state with a reduced diameter and a self-expanding state with an increased diameter when an externally applied mechanical force is withdrawn; proximal and distal ends of the self-expanding stent retriever are fixed to the pusher member at respective proximal and distal fixation points; the self-expanding stent retriever is capable of separating or releasing from the pusher member at the respective proximal and distal fixation points; A semi-compliant balloon housed within the self-expanding stent retriever and fixed to the pusher member axially extending through the semi-compliant balloon; And An inflation lumen axially defined within the pusher member and in fluid communication with the semi-compliant balloon, wherein the proximal and distal ends of the self-expanding stent retriever are releasably fixed to the pusher member via respective proximal and distal sleeves, wherein the proximal and distal ends of the self-expanding stent retriever are capable of being released from the respective proximal and distal sleeves only when the semi-compliant balloon is inflated and the self-expanding stent retriever is in a super-expanded state, the diameter of the self-expanding stent retriever in the super-expanded state being greater than the diameter in the self-expanding state.

Images