Method and apparatus for delivering stent

Abstract

To provide a method, apparatus, and kit for assisting in the expansion of a self-expanding stent, especially within highly curved or tortuous blood vessels.SOLUTION: An elongated pusher 112 having an expandable distal mesh portion can be positioned within a self-expanding stent, expanding during delivery to provide extra expansion force to the stent to ensure the stent properly expands.SELECTED DRAWING: Figure 3

Description

[Technical field]

[0001] [Related Applications] This application claims priority to U.S. Provisional Patent Application No. 62 / 404,102, filed October 4, 2016, entitled "METHODS FOR STENT DELIVERY AND USE," which is hereby incorporated by reference in its entirety. [Background technology]

[0002] Stents are generally tubular devices that are delivered to a patient's vascular system by a catheter or similar delivery device. Stents can be used to treat a variety of conditions, including stenosis and aneurysms. When used to treat stenosis (narrowing of a blood vessel), stents are used to push blood clots through the vessel, allowing normal blood flow. When used to treat aneurysms, low-porosity stents can be used to restrict blood flow to the vessel (so-called flow-diverting stents) to promote aneurysm clotting and reduce the risk of aneurysm rupture. Alternatively, stents can be used as a scaffolding material to retain other embolic materials (such as embolic coils) within the aneurysm.

[0003] Stent delivery is usually easy when the stent is placed in a substantially straight portion of the blood vessel. As an example, the distal end of the delivery catheter can be advanced near the desired delivery location, the outer sheath can be withdrawn, and the stent can be expanded within the blood vessel. Even in these straight vessels, stent delivery can still be difficult due to variables such as the size of the stent, the size of the delivery catheter, and the size of the blood vessel. When the stent needs to be placed in or near a bent or highly curved portion of the blood vessel, a self-expanding stent can be difficult to properly place. As an example, FIG. 1 shows a self-expanding stent 12 (such as that described in U.S. Patent No. 5,399,323, which is incorporated herein by reference in its entirety) placed in a highly curved portion of a blood vessel 10. When the catheter 14 releases the stent 12, the stent forms a flat or folded portion 12A against the outer curved surface of the blood vessel 10. FIG. 2 shows a second flat or folded portion 12A formed against the outer surface of a second curve of the blood vessel 10 when the stent 12 is further expanded. When a folded section 12A occurs, the physician's only alternative is to try rotating the catheter 14 and / or partially retract and reposition the stent 12. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] U.S. Pat. No. 9,439,791 Summary of the Invention

[0005] The present invention is directed to methods, devices and kits for assisting the expansion of self-expanding stents, especially in highly curved or tortuous vessels.

[0006] In one embodiment, a stent delivery device is directed to an elongated pusher having a self-expanding mesh section at its distal end. The mesh section preferably includes one or more mesh valve sections connected to each other by a region of reduced diameter. Optionally, various regions of the mesh section, such as the intermediate region of the valve sections, can have a denser braided section with a higher pic per inch.

[0007] In one embodiment, the mesh portion is disposed on a core wire extending from a distal end of the pusher, the mesh portion is longitudinally slidable on the core wire, the proximal end can be fixed to the core wire or the pusher, or the distal end can be fixed to the core wire.

[0008] The mesh portion can include one bulb portion, or can include multiple bulb portions (e.g., 2-10, or more). Additionally, the bulb portions can have a variety of shapes, such as spherical, spheroidal, elongated cylinders, cones, or diamonds.

[0009] In one embodiment, the core wire can terminate at the distal end of the pusher or partway within the first valve section, allowing the assist device to be more flexible and to tolerate a greater degree of vascular curvature by not extending all the way to the end of the mesh section.

[0010] In one embodiment, structural wire members extend between the valve sections and above the reduced diameter region and are utilized to capture clots or other debris dislodged during the stent delivery procedure.

[0011] In one embodiment, a distal protection device is included at the distal end of the device. The distal protection device can include a relatively large expandable mesh valve section that includes a filter or similar structure to capture any material dislodged during stent deployment. The distal protection device can be integrally braided with the mesh section or can be a separate structure connected near the distal end of the core wire.

[0012] The present invention is also directed to a method of deploying a stent, comprising the steps of exposing a distal portion of the stent within a curved region of the vasculature, expanding a mesh portion of a stent-assisted device within the stent to apply a radial expansive force to the interior of the stent, properly deploying the stent, and withdrawing the stent-assisted device.

[0013] The present invention is also directed to a kit that includes a catheter, a pusher within the catheter, a self-expanding mesh portion attached to a distal end of the pusher, and a stent disposed over the mesh portion.

[0014] These and other aspects, features, and advantages of the permissible embodiments of the present invention will become more apparent and obvious from the following description of the embodiments of the invention, taken in conjunction with the accompanying drawings. [Brief description of the drawings]

[0015] [Figure 1] FIG. 1 shows a stent placed in a bent portion of a blood vessel. [Diagram 2] FIG. 2 further illustrates the stent of FIG. 1 positioned in a bent portion of a blood vessel. [Diagram 3] FIG. 3 illustrates one embodiment of a stent-assisted device according to the present invention in an expanded configuration. [Figure 4] FIG. 4 shows the distal end of the stent-assisted device of FIG. 3 within a stent in accordance with the present invention. [Diagram 5] FIG. 5 illustrates the stent-assisted device of FIG. 3 within a stent in accordance with the present invention. [Figure 6] FIG. 6 illustrates the stent assist device of FIG. 3 to assist in the placement of a stent within a tortuous vasculature. [Figure 7] FIG. 7 illustrates the stent assist device of FIG. 3 assisting further placement of the stent of FIG. [Figure 8] FIG. 8 shows another embodiment of a stent-assisted device according to the present invention. [Figure 9] FIG. 9 illustrates another embodiment of a stent-assisted device having multiple mesh valve portions in accordance with the present invention. [Figure 10] FIG. 10 shows several different possible shapes for the mesh valve portion of the present invention. [Figure 11] FIG. 11 illustrates another embodiment of a stent-assisted device according to the present invention having a core wire that terminates within a proximal portion of the mesh portion. [Figure 12] FIG. 12 illustrates the stent-assisted device of FIG. 11 within a stent in accordance with the present invention. [Figure 13] FIG. 13 illustrates the proximal valve portion of the stent-assisted device of FIG. 11 in accordance with the present invention. [Figure 14] FIG. 14 illustrates the distal tip of the stent-assisted device of FIG. 11 in accordance with the present invention. [Figure 15] FIG. 15 illustrates a stent-assisted device having a wire frame member between the valve sections in accordance with the present invention. [Figure 16] FIG. 16 shows a stent-assisted device having a distal protection device attached to a mesh portion in accordance with the present invention. [Figure 17] FIG. 17 illustrates a stent-assisted device having a distal protection device separate from the mesh portion in accordance with the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0016] Specific embodiments of the present invention will now be described with reference to the accompanying drawings. However, the present invention may be embodied in various configurations and should not be construed as being limited to the embodiments set forth herein. Instead, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the present invention to those skilled in the art. The terminology used in the detailed description of the embodiments set forth in the accompanying drawings is not intended to be limiting of the present invention. In the drawings, like numbers refer to like elements.

[0017] The present invention is generally directed to a device that is expandable within the internal passageway of a self-expanding stent 12 upon deployment to provide additional expansive force to assist in radially expanding the self-expanding stent 12 and to maintain it in a radially expanded state. This additional expansive force may be particularly useful in highly tortuous vessels 10 that tend to cause the stent 12 to form folded portions 12A, as shown and described with respect to Figures 1 and 2.

[0018] It is noted that in FIG. 3 and those that follow, unless otherwise indicated, everything to the right of the drawing is considered distal (towards the patient / patient's vasculature) and everything to the left of the drawing is considered proximal (away from or outside the patient / patient's vasculature).

[0019] 3 illustrates an expandable stent-assisted device 100 according to one embodiment of the present invention. The stent-assisted device 100 may be thought of as a distal portion of a broad range of delivery systems or pushers used to mechanically push or deliver a stent 12. The stent-assisted device 100 includes a pusher body 112 having an elongated tubular shape terminating in a radiopaque (e.g., tantalum) marker band 109 and a stationary or fixed core wire 104 exposed distally of the pusher body 112.

[0020] In one embodiment, the core wire spans the lumen of the pusher body 112 with only a distal portion of the core wire 104 exposed. In another embodiment, the core wire 104 is attached to the distal end of the pusher body 112. The core wire 104 includes a fixed radiopaque marker band 107. In one example, the stent 12 can include multiple proximally disposed flared ends or loops with an enlarged marker coil region, one or more of which are disposed within the marker bands 109 and 107 at location 104A to retain the stent during delivery. The enlarged marker coil region keeps the flared loops of the stent anchored between the marker bands 107 and 109. The marker bands 107, 109 can have a size of about 0.0135 inches in diameter and the core wire 104 is about 0.003 inches in diameter. The stent assumes a first, folded configuration when placed within the delivery catheter 14, which is best seen in FIGS. 4-5. When the pusher body 112 is pushed beyond the distal end of the catheter 14, or when the catheter 14 is retracted, the stent expands to its heat-set, expanded shape. A similar stent and delivery system configuration is found in the previously incorporated US Pat. No. 6,393,633, in which the retained stent loop flares expand and are not retained in position 104A when the stent is pushed sufficiently out of the catheter 14.

[0021] The stent assist device 100 further includes a mesh portion 102 disposed along the core wire 104. The purpose of this mesh portion is to provide an additional radially outward force to the stent 12 to assist in the expansion of the stent 12 and maintain its expanded shape during the procedure. The mesh portion 102 is formed from multiple wires and is heat set into the expanded shape such that the mesh portion self-expands upon release from the overlying delivery catheter 14.

[0022] Preferably, the mesh portion 102 is braided and heat set to form one or more valve sections 102A (e.g., two valve sections as shown in FIG. 3, or more are possible), each connected by a reduced diameter section 102B. The mesh portion includes multiple crimp points (proximal crimp point 108, distal crimp point 106). The crimp points 106, 108 can be made by crimping the wire itself, welding, gluing, or using metal bands (e.g., radiopaque marker bands). In various embodiments, the crimp points 106-108 can float / slide over the core wire 104 or be fixed to the core wire 104 in the manner described below.

[0023] The mesh portion 102 can be woven in a variety of configurations, for example, 12, 16, 24, 36, or 48 wires can be woven together in a 1×1, 1×2, or other wire configuration.

[0024] The porosity or opening size of the mesh portion 102 in the expanded configuration can vary along the length of the mesh portion 102. In the embodiment shown in Figure 3, the radially central portion 102C of the valve portion 102A has a lower porosity (i.e., more wires or more pics per inch). This creates a stronger, more reinforced region of the mesh portion 102 that can provide a greater radial outward force and is less likely to tangle with the wires of the stent 12 when the stent 12 contacts the mesh portion 102.

[0025] Other embodiments may have other portions of mesh portion 102 reinforced in this manner, such as the ends of bulb portion 102A or reduced diameter region 102B. In one embodiment, the wires of mesh portion 102 include Nitinol and have a diameter in the range of about 0.001 inch to 0.0015 inch. Radiopaque (e.g., Tantalum) wires may also be included in the mesh to provide increased visibility and areas of increased stiffness in the braid to further improve contact force against the overlying stent 12. Dawn-filled tubing with a Nitinol jacket and a Tantalum core, or vice versa, may also be used.

[0026] Mesh portion 102 can be made in a variety of ways. By way of example, a mandrel having a bulb region shaped similar to bulb portion 102A and a reduced diameter region shaped similar to region 102B may be used to make the mesh portion shape. Wire can be woven onto the mandrel and then heat set to impart the shape, or a tube of prewoven mesh can be placed onto the mandrel and heat set.

[0027] Alternatively, a mandrel of uniform cylindrical diameter may be used, and the mesh portion 102 may first be woven over the mandrel. The mesh portion 102 may then be removed from the mandrel and strings or marker bands may be selectively added in place to create the reduced diameter regions 102B, followed by a subsequent heat treatment to provide the shape shown in FIG.

[0028] In one embodiment, core wire 104 maintains a fixed position relative to other components of pusher body 112. Crimp point 108 is fixed to core wire 104, while crimp point 106 slides or floats longitudinally on core wire 104. Because the braided mesh structure tends to reduce in length as it radially expands, longitudinally slidable crimp point 106 allows the distal end of mesh portion 102 to move proximally as mesh portion 102 becomes exposed from catheter 14 and begins to radially expand.

[0029] If the stent 12 is too oversized relative to the vessel, there will be a large radial force against the vessel wall that can jam the stent 12. This can also cause the mesh portion 102 to jam because it is also too oversized relative to the vessel and therefore jams within the vessel or relative to the wires of the stent. To avoid the situation where the mesh portion 102 gets jammed in the expanded configuration, the core wire can include a fixed marker band 110 between the two crimp points 106, 108, which acts as a backstop to ensure that the crimp point 106 cannot be shortened too proximally.

[0030] Other embodiments are possible, including configurations in which either one of the crimp points 106, 108 is fixed or slidable, or situations in which the crimp points 106, 108 are both fixed or both slidable. To achieve a slidable crimp point, the crimp point inner diameter needs to be at least slightly larger than the core wire diameter. In one embodiment, the core wire may be about 0.003 inches in diameter, while any sliding crimp point may have an inner diameter of about 0.005 to 0.006 inches. To create a fixed crimp point, in one embodiment, the crimp point may be mechanically attached to the core wire 104 using a crimping tool, adhesive, or welding.

[0031] The core wire 104 may comprise Nitinol. As best shown in FIG. 4, the distal end of the core wire 104 includes a relatively soft distal tip 114, for example, comprised of a tantalum or platinum wire coiled around an underlying Nitinol wire. The tantalum or platinum coiled wire aids visualization so the user knows where the distal end of the wire 104 is positioned, while the coil provides increased flexibility so that the portion 114 does not get stuck against the vessel wall when it hits it. The soft distal tip 114 may have a pre-adjusted J-shape as shown in FIG. 4, or may be fusible so that the user can impart this J-shape on a given mandrel. The angled J-shape is particularly useful when guiding the system through a vessel bifurcation. This distal tip may eliminate the need for a separate guidewire to track catheters and stents to the target treatment area.

[0032] 4-5 generally illustrate how the stent 12 assumes its expanded configuration upon delivery and how the mesh portion can support and assist in opening the stent. In FIG. 4, the stent 12 is being released from the catheter 14 and the distal portion of the stent 12 assumes its expanded shape. In FIG. 5, the mesh portion 102A expands against the proximal portion of the stent 12 to provide a scaffolding force against the proximal portion of the stent 12 to assist in opening the stent. In FIG. 5, the mesh portion uses only one valve portion 102A or the stent 12 is only partially deployed such that a limited amount of the stent 12 is exposed corresponding to only the distal portion of the mesh portion 102.

[0033] In operation, as seen in Figures 6 and 7, the distal end of the catheter 14 is advanced to or near the area where the physician wishes to place the stent 12. The catheter 14 is then retracted from the stent 12, or the stent 12 is pushed outward from the interior passage of the catheter. Once the stent 12 is positioned around the curved portion of the patient's blood vessel 10, the mesh portion 102, and particularly the beaded portion 102A, radially expands and pushes outward from within the stent 12, supporting and opening the stent as shown in Figure 7.

[0034] The catheter often includes a radiopaque marker band located 3 centimeters from its distal tip, so that the user can line up the marker band located anywhere along the delivery pusher to determine the location of the proximal end of the stent. In this regard, the physician can determine when the stent is fully deployed or nearly fully deployed based on the longitudinal position of the pusher. In FIG. 3 and described above, a marker band 109 connected to the pusher body 112 and a marker band 107 along the core wire 104 are described. Either of these markers can be aligned with the 3 centimeter marker on the catheter to determine that the stent is fully deployed or nearly fully deployed. Once the stent 12 is fully deployed, the pusher body 112 is retracted proximally to return the mesh portion 102 to the passageway of the catheter 14.

[0035] In some embodiments, the core wire 104 is freely movable relative to the body of the pusher body 112. This movable core wire 104 allows a physician to manually control the expansion and / or contraction of the mesh portion 102 corresponding to the configuration of the crimp points 106 and 108.

[0036] 8 illustrates such an embodiment of a stent assist device 120 in which the core wire 104 is movable independently of the pusher body 112 to selectively increase the diameter of the mesh valve portion 102A to increase the radial pushing force against the overlying stent 112. In this embodiment, the pusher body 112 includes a lumen extending along its length and opening at its proximal and distal ends. The core wire 104 can be pushed and pulled through the lumen independently of the pusher body 112, and the proximal end of the core wire 104 can be manipulated independently of the pusher body 112 by a user / physician.

[0037] The proximal crimp point 108 is fixed to the pusher body 112 or the core wire 104. If the proximal crimp point 108 is fixed to the core wire 104 (rather than fixed to the pusher body 112), the proximal crimp point 108 is located relatively close to the pusher body 112 such that upon retraction of the core wire, the crimp point immediately abuts the pusher body 112, preventing further proximal movement of the mesh portion 102. The distal crimp point 106 is longitudinally movable on the core wire 104. The core wire 104 includes another fixed distal marker band 122 that is distal to the mesh crimp point 106 and is fixed to the core wire. As the user / physician retracts the core wire 104, the distal marker band 122 contacts the crimp point 106 and, due to the slidability of the crimp point 106, the crimp point 106 moves proximally inward, increasing the radial profile of the mesh portion 102A as the mesh portion 102A contracts longitudinally due to the compressive force exerted by the distal marker 122. In this manner, the user can selectively increase the radial expansion force exerted on the stent by independently controlling the diameter of the mesh valve portion 102A. The marker band 110 provides a backstop surface that limits how much the distal crimp point 106 can float, as in the embodiment of FIG.

[0038] Another embodiment is similar to device 120 of FIG. 8. However, in this embodiment, the lumen of pusher body 112 is larger than crimp points 106, 108 such that pulling corewire 104 proximally can retract all or a portion of mesh portion 102A into pusher body 112. Proximal crimp point 108 is slidable over corewire 104, while distal crimp point 106 is fixed to corewire 104. Retracting corewire 104 causes proximal crimp point 108 to enter delivery pusher body 112. Further retraction of corewire 104 can also cause mesh portion 102 to enter pusher body 112 (depending on how oversized the inner diameter of pusher body 112 is compared to mesh portion 102). However, the ability to retract the proximal portion of mesh portion 102 within pusher body 112 also allows the user to customize how much contact mesh portion 102 has with the overlying stent.

[0039] In one embodiment, the core wire is in a first retracted configuration with all or a portion of the mesh portion 102 housed within the pusher body 112. The user then delivers the stent 12, and if there is a tracking issue with the stent 12 getting stuck at a bend where a portion of the stent does not open, the user can push the core wire distally, exposing the mesh portion 102 and allowing the mesh valve portion 102A to contact and push open the stent 12. This is primarily accomplished by the sliding of the proximal crimp point 108 in this embodiment, as this allows the mesh portion 102 to expand longitudinally and contract radially.

[0040] Alternatively, this functionality is also possible if the proximal crimp point 108 is fixed to the core wire 104 but the distal crimp point 106 is slidable relative to the core wire 104. In this configuration, when the core wire 104 is retracted into the pusher body 112, the proximal crimp point 108 enters the pusher body 112, and as more mesh portion 102 is retracted into the pusher body 112, the mesh portion 102 expands longitudinally to push the slidable distal crimp point 106 distally, which allows for continuous radial contraction and longitudinal expansion of the mesh portion 102. On the other hand, if both crimp points 106, 108 are fixed, the mesh portion 102 has a relatively constant shape and it becomes difficult to obtain a radially compressed and longitudinally expanded shape to fit within the pusher body 112.

[0041] 9 illustrates a stent-assisted device 130 having six valve portions 102A instead of the two valve portions 102A generally shown in the stent-assisted device embodiments of the previous figures. It is contemplated that many valve portions 102A may be included as part of the mesh portion (e.g., 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10 or more valve portions). The number, length, and diameter of these valve portions 102A may be selected to correspond together to the length and expansion diameter of the particular stent 12 being used.

[0042] In addition to varying numbers of valve portions 102A, the valve portions 102A can have a variety of shapes (e.g., all valve portions have the same shape, or there are a variety of shapes). Figure 10 shows example valve shapes including a sphere shape 132, a spheroid 133, an elongated cylinder 134, a proximally increasing cone shape 135, a proximally decreasing cone shape 136, or a diamond-like shape with proximal and distally decreasing tapered cone sections 137. These shapes can be imparted to the mesh portion 102 by braiding the mesh portion 102 over a mandrel having the desired shape (e.g., a mandrel having the same shape as the mesh shape of Figure 10) and then heat setting to impart the expanded shape. Alternatively, these shapes can be created by braiding mesh 102 over a mandrel having a uniform, fixed shape (e.g., cylindrical), heat setting the shape on the mandrel, removing mesh portion 102, and tying or selectively placing marker bands around portions of the shape to achieve the shape shown in FIG. 10.

[0043] The previous embodiment described a core wire 104 spanning the entire mesh portion 102, where the mesh portion 102 was placed directly onto the core wire 104. Other embodiments may use a core wire 104 that terminates proximal to the distal end of the mesh portion 102. This prior termination point may give the mesh portion some independence to conform to the bending conditions of the vasculature and further aid in adequate stent expansion.

[0044] By way of example, Figures 11, 12, 13, and 14 show another embodiment of a stent-assisted device 140 in which the core wire 104 terminates within or proximal to the mesh portion 102. Looking to Figure 11, a core wire tip portion 142 of the core wire 104 is disposed within the first-most proximal valve section 102A. In one embodiment, the core wire tip 142 may be a Nitinol wire or a platinum or tantalum wire coiled around the distal end of the core wire 104. In another embodiment, the core wire 104 terminates within the body of the pusher body 112, exposing only the core wire tip 142 (e.g., a platinum or tantalum wire coiled around a Nitinol wire) within the first-most proximal valve section 102A. This tip portion 142 is seen in the enlarged view of Figure 13. The proximal end of mesh portion 102 is secured to the body of pusher body 112 either directly or immediately adjacent to the body of pusher body 112 via proximal crimp point 108 .

[0045] Optionally, the distal end of the mesh portion 102 may include a distal tip 114 that connects to the distal end of the mesh portion 102, similar to the previously described embodiment, to provide a guiding surface under the stent 12 and to provide a soft vessel contacting surface to aid in placement of the stent 12 without causing vessel trauma. As best shown in FIG. 14, the distal tip 114 includes an underlying nitinol wire with a proximal laser weld ball 114A in the distal-most mesh valve portion 102A. A coil 114B of tantalum or platinum wire is wound around the nitinol wire and the distal-most portion of the mesh portion 102. A coil 114C of platinum or tantalum wire is also wound around the nitinol wire, intertwining with a portion of the tantalum-platinum coil 114B and extending along the remaining distal length of the nitinol wire. Optionally, adhesive or welding may be used on the distal end of the tip 114. Additionally, a portion of the underlying nitinol wire may be flattened or shaped.

[0046] When a stent is deployed in a patient, the thrombus may become dislodged and migrate downstream, potentially resulting in further complications downstream in the vasculature. The following description is directed to embodiments utilized to harvest or capture thrombus dislodged during a stent deployment procedure.

[0047] 15 shows an embodiment of a stent assist device 150 that utilizes a mesh portion 102 with wire frame members 152 extending between the expanded valve portions 102A. These wire frame members 152 provide additional structural support to the valve portions 102A and can be utilized to collect and capture blood clots that may form during the procedure. These wire frame members 152 are preferably constructed from wires of the same or larger diameter than those that make up the mesh portion 102 and are attached to the wires of the mesh portion 102, the underlying core wire 104, or a combination of each such that the wire frame members 152 expand and contract with the mesh portion 102.

[0048] In one embodiment (shown in FIG. 15), four equidistant wire frame members 152 are used, each of which, when expanded, forms an outward arc shape similar in diameter to the valve portions 102A. However, the wire frame members 152 could alternatively have a spiral shape around the mesh portion 102, a straight shape between the valves 102A, or a similar geometric shape.

[0049] 16-17 show an embodiment of a stent-assisted device having a distal mesh element to capture dislodged thrombus. In FIG. 16, the stent-assisted device 160 uses a mesh portion 102 having a relatively large mesh valve portion 162 including a recessed filter 164 that acts as a distal guard during the procedure to capture clots, thrombus, or other debris that may be dislodged during deployment of the stent 12. The recessed filter 164 can be constructed of fine mesh, fabric, polymer film, or similar known filter materials. Additionally, other filter 164 shapes are possible, such as a circular planar shape. The larger mesh valve portion 162 can be woven from the wires of the mesh portion 102 to form an interconnected mesh structure. During the procedure, the mesh valve portion 162 can be advanced distally beyond the stent 12 (or placed in front of the stent 12) so that it expands in front of the stent 12 and contacts the vessel.

[0050] 17, the mesh valve portion 162 can be separate from the mesh portion 102 and secured near the distal end of the core wire 104. This location allows the physician to more easily position the valve portion 162 and filter 164 prior to or at the initiation of deployment of the stent 12. This separate mesh valve portion 162 can be configured to slide longitudinally over the core wire 104 or can be locked in place from sliding.

[0051] The embodiments disclosed herein utilize a common delivery pusher body 112 that is used to deliver the stent 12 and the mesh portion 102. Other embodiments may utilize a stent 12 that connects to a first elongated delivery pusher having a passageway. A second pusher body 112 of the stent-assisted device is positioned within the first pusher to allow the user to move the stent and stent-assisted device separately and independently.

[0052] It should be understood that the present invention is also directed to a kit that includes a guide tube, a pusher body 112 disposed within the guide tube, any of the stent-assisted embodiments described herein attached to the pusher body 112, and a stent disposed near the distal end of the guide tube and on the mesh portion 102 of the pusher body 112. In use, a physician can connect the guide tube to the proximal hub of the catheter 14 and advance the pusher (including the mesh portion 102) and stent 12 into the catheter 14.

[0053] Although the present invention describes separate components such as the pusher body 112, the core wire 104, and the mesh portion 102, it should be understood that one or more of these components may also be considered a pusher, a stent-assist system, or a stent-assist device.

[0054] Although the present invention has been described with respect to specific embodiments and applications, those skilled in the art can implement further embodiments and modifications from this teaching without departing from the spirit or scope of the present invention. It is therefore understood that the drawings and descriptions herein are presented by way of example to facilitate understanding of the present invention and should not be construed as limiting its scope.

Claims

1. An elongated pusher body; a mesh portion connected to a distal end of the elongate pusher body, the mesh portion further having a compressed configuration and a radially expanded configuration; a stent engaged with the elongated pusher body and positioned over the mesh portion; A stent delivery device, wherein the mesh portion expands radially against the interior of the stent when the stent is deployed from a catheter.

2. The stent delivery device of claim 1 , wherein the mesh portion, in its radially expanded configuration, includes a first valve shape, a second valve shape, and a reduced diameter shape between the first valve shape and the second valve shape.

3. The stent delivery device of claim 1 , wherein the pusher body further comprises a core wire, at least a portion of the core wire being exposed from a distal end of the pusher body, and the mesh portion being disposed about the core wire.

4. 2. The stent delivery device of claim 1, wherein a proximal end of the mesh portion is connected at a distal end of the elongate pusher body and a core wire extends from the elongate pusher body into the mesh portion and terminates in a proximal-most valve portion of the mesh portion.

5. The stent delivery device of claim 2 , further comprising a plurality of structural wires extending between the first valve configuration and the second valve configuration and disposed above the reduced diameter configuration.

6. The stent delivery device of claim 3 , wherein the mesh portion slides longitudinally on the core wire.

7. The stent delivery device of claim 3 , wherein a distal end of the mesh portion slides over the core wire and a proximal end of the mesh portion is longitudinally fixed relative to the core wire.

8. The stent delivery device of claim 3 , wherein a proximal end of the mesh portion is secured to a distal end of the pusher body.

9. The stent delivery device of claim 3 , further comprising a marker band secured to the core wire and disposed within the mesh portion.

10. 4. The stent delivery device of claim 3, wherein the mesh portion further comprises a third valve shape disposed distal to the first and second valve shapes, the third valve shape having a larger expanded diameter than the first and second valve shapes, and further comprising a filter disposed within the third valve section and configured to filter blood for debris.

11. 4. The stent delivery device of claim 3, further comprising a third valve shape disposed distally from and spaced apart from the first and second valve shapes, the third valve shape having a larger expanded diameter than the first and second valve shapes, and further comprising a filter disposed within the third valve section and configured to filter blood for debris.

12. an induction tube having a passage; a stent compressed and positioned in the passageway adjacent the distal end of the guide tube; an elongated pusher body disposed within the passage of the guide tube; a mesh portion having a compressed configuration and a radially expanded configuration, the mesh portion being positioned within an interior of the stent such that when the stent is exposed from a distal end of a catheter, the mesh portion radially expands to apply a radial force against the interior of the stent.

13. 13. The stent delivery kit of claim 12, wherein the mesh portion, in its radially expanded configuration, includes a first valve shape, a second valve shape, and a reduced diameter shape between the first valve shape and the second valve shape.

14. The stent delivery kit of claim 12 , further comprising a core wire, at least a portion of said core wire being exposed at a distal end of said elongate pusher body, and said mesh portion being disposed about said core wire.

15. The stent delivery kit of claim 12 , wherein the mesh portion comprises a plurality of bulb shapes in its radially expanded configuration.

16. 16. The stent delivery kit of claim 15, wherein each of the plurality of valve shapes has a shape selected from a shape comprising a sphere, a spheroid, an elongated cylinder, a cone, or a proximally increasing and a proximally decreasing cone shape.

17. 1. A method of deploying a stent, comprising: advancing a distal end of the catheter adjacent a curved portion of a blood vessel; exposing a distal portion of the stent; and expanding a mesh portion within the stent to apply an outward radial force to the stent.

18. 20. The method of claim 17, further comprising retracting a pusher body connecting the mesh portion to retract the mesh portion into the catheter.

19. 20. The method of claim 18, wherein expanding the mesh portion further comprises expanding a first valve portion and a second valve portion of the mesh portion.

Images