Repositionable intracranial stent with recovery mechanism

Abstract

A stent device is described. The stent device comprises a stent (105) and a stent delivery system. The stent (105) comprises a cylindrical portion forming a stent frame having an outer mesh network of a plurality of interconnected segments, the stent frame being arranged to apply a radial force to an inner wall of a blood vessel. The stent delivery system includes a locking mechanism arranged to engage with the proximal end of the stent frame when wrapped in the sheath, and a push wire (103). The locking mechanism comprises a proximal positioning disk (102) and a distal positioning disk (100), the distal positioning disk (100) having a plurality of grooves (101) arranged to engage with the same number of struts (109) formed on the proximal end of the stent (105).

Description

[0001] Related Applications

[0002] This application claims priority to U.S. patent application 17 / 729,842, filed on April 26, 2022. Technical Field

[0003] The present invention relates generally to the field of intravascular treatment devices and delivery systems, and more particularly to expandable stents and corresponding delivery systems. The present invention particularly relates to very small expandable stents and delivery systems for use in neurovascular anatomy or similar vascular anatomy to treat occluded vessels, aneurysms or other vascular diseases. Background Art

[0004] Vascular diseases, particularly those affecting the neurovascular system, including intracranial atherosclerotic disease (ICAD) and aneurysms, are an important focus for innovation. In 2020, cerebrovascular disease was the fifth leading cause of death in the United States, according to the Centers for Disease Control and Prevention (CDC).

[0005] Stents and similar stent implantation techniques have been successfully used in larger vessels in both the cardiovascular and peripheral spaces. However, due to the smaller diameter of vessels in the neurovasculature, stents and stent implantation techniques that have been used in larger vessels such as the coronary arteries and peripheral structures and used in the smaller neurovasculature can cause additional complications.

[0006] Stenting involves accessing a patient's vascular system and deploying a mesh tube to provide structural support to the blood vessel. This may be to treat vessels that have fatty deposits or plaque buildup, also known as atherosclerosis, or to support vessels that are damaged or have questions about their structural integrity. In the neurovascular system, stenting is most notably used to prevent stroke or treat recurrent stroke.

[0007] Stents can be self-expanding or can be expanded by mechanical methods such as a balloon. After manufacturing, the stent is loaded onto an appropriate delivery system, either within a guide sheath for a self-expanding stent or on a balloon catheter for a non-self-expanding stent. During the procedure, the interventionalist will use a variety of accessories to locate the treatment site, typically including an introducer, guide catheter, guidewire, microcatheter, and fluorescent imaging technology. The interventionalist will then insert the delivery system into a guide catheter or microcatheter sized appropriately for the anatomy being treated. The delivery system with the preloaded stent will then be advanced to the target location and deployed by withdrawing the guide catheter or microcatheter for a self-expanding stent, or applying internal pressure to the balloon catheter to mechanically force the stent to open for a non-self-expanding stent.

[0008] Stent implantation in small, tortuous vessels such as the neurovasculature presents additional challenges due to the tortuosity of the anatomy and the reduction in vessel size. The increased tortuosity of the neurovasculature requires that the devices used be more flexible, and the reduction in vessel size requires that the devices and any accessories be downsized to fit into the smaller vessels. Because the vessels of the neurovasculature are small and tortuous, devices used in this part of the anatomy must be specially designed to work properly. Special consideration must also be given to the limited use of assistive devices, as implanting multiple devices simultaneously in the neurovasculature may be difficult or impossible.

[0009] When delivering a stent, accuracy of stent placement is critical to ensure that the stent is as effective as possible. In more tortuous anatomies, such as near bifurcations or aneurysms, accuracy of stent placement is critical. If a stent is not accurately placed beyond the intended vessel wall and into a patent vessel, the patient is at great risk for thrombosis. This risk is increased in critical anatomies such as the neurovasculature, where improper stent placement may increase the patient's risk of stroke. In larger vessels, established techniques exist for using auxiliary devices such as additional guidewires or balloon catheters, which can improve the accuracy of stent placement. In the neurovasculature, the reduced diameter and tortuosity of the vessel either preclude the use of these techniques or increase their risk and / or difficulty. Therefore, there is a need for a stent and stent delivery system that can improve the accuracy of stent placement without the need for accessories or advanced techniques.

[0010] One approach to provide additional stent placement accuracy is to allow the stent to be recaptured before it is fully deployed. This would provide the interventionalist with an opportunity to reposition the stent if it is not positioned in the desired location.

[0011] US 7,309,351 discloses a stent that can be recaptured prior to full deployment. More specifically, US 7,309,351 discloses a self-expanding stent in which the ends of the stent are composed of struts surrounded by coils. The delivery system is a variable diameter coil, where the diameter changes in accordance with the stent strut coil diameter. The coiled ends of the stent then interact with a delivery wire to anchor the device in place until the ends are exposed. However, the stent and stent implantation techniques disclosed in US 7,309,351 introduce two (2) undesirable design limitations. First, by design, the anchoring member requires at least one end of the stent to have an additional coil, resulting in an inconsistency in stent geometry that may promote the generation of thrombi after implantation. Second, in order to make the delivery system compatible with standard neurovascular attachments (such as microcatheters), the stent must have very thin struts to accommodate the additional volume introduced by the coils at both ends of the stent and the mating coils on the delivery system. The thin struts required for a viable solution have a severe negative impact on the radial strength of the stent, reducing the overall effectiveness during and after implantation. Although the stent disclosed in US 7,309,351 allows recapture, it does not allow repositioning of the stent without sacrificing patient outcomes or introducing additional risk.

[0012] Therefore, there remains a need to provide repositionable low-profile stents and their corresponding delivery systems that can meet the functional requirements for effectively treating vascular disease without sacrificing patient outcomes or introducing additional risks. Summary of the invention

[0013] Through various embodiments of the present invention, at least the above-mentioned needs are solved and technical solutions are achieved in the art. In some embodiments of the present invention, the stent device includes a stent and a stent delivery system. The stent includes a cylindrical portion forming a stent frame, the stent frame having an external grid network of multiple interconnected segments, and the stent frame is configured to apply radial force to the inner wall of the blood vessel. The stent delivery system includes a locking mechanism and a push wire, and the locking mechanism is configured to engage with the proximal end of the stent frame when coated in a sheath or a microcatheter. The locking mechanism includes a proximal positioning disc and a distal positioning disc, and the distal positioning disc has a plurality of grooves, and the grooves are configured to engage with an equal number of struts formed on the proximal end of the stent.

[0014] In some embodiments of the present invention, the locking mechanism of the stent delivery system is further configured to engage with a plurality of struts of the stent when the stent is in a partially deployed state to allow the stent to be retracted to a non-deployed state.

[0015] In some embodiments of the present invention, the distance between the position of the distal positioning disc and the position of the proximal positioning disc corresponds to the length and radius of the proximal apex of the stent framework.

[0016] In some embodiments of the present invention, each of the plurality of slots of the distal positioning plate has a size greater than each of the plurality of struts of the stent to allow the proximal end of the stent frame to be located within the plurality of slots.

[0017] In some embodiments of the present invention, the locking mechanism of the stent delivery system is further configured to disengage from a plurality of struts of the stent when the stent is in a fully expanded state to allow the stent to be released in situ.

[0018] In some embodiments of the invention, the proximal end of the stent framework has an open geometry that allows the angle on the proximal vertex to be larger in the fully expanded state than in the undeployed state. In some embodiments of the invention, the proximal end of the stent framework includes two parallel struts connected by arcuate ends in the curled state. In some embodiments of the invention, the angle of the proximal vertex on the proximal end of the stent framework is large enough in the expanded state to cause the proximal end of the stent to tilt radially inward toward the central axis of the cylinder in the undeployed state.

[0019] In some embodiments of the invention, the stent further comprises at least one fluorescent element visible under fluorescent imaging. In some embodiments of the invention, at least one of the distal positioning disc or the proximal positioning disc comprises at least one fluorescent element visible under fluorescent imaging.

[0020] These and other embodiments of the invention are discussed in detail below. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] It should be understood that the drawings are used to illustrate various aspects of the embodiments and may include elements that are not drawn to scale.It should be noted that the same reference numerals in different figures represent the same objects.

[0022] Figure 1 A view showing a stent delivery system according to an embodiment of the present invention.

[0023] Figure 2 A side view of a stent and a stent delivery system in an undeployed state is shown according to an embodiment of the present invention.

[0024] Figure 3 A top view of a stent and a stent delivery system in an undeployed state according to an embodiment of the present invention is shown.

[0025] Figure 4 A side view of a stent encased in a tube and a stent delivery system in an undeployed state is shown according to an embodiment of the present invention.

[0026] Figure 5A side view of a stent and stent delivery system in a partially deployed state is shown, wherein an introducer sheath or microcatheter has been partially retracted to expose the distal end of the stent but not the proximal end of the stent, according to an embodiment of the present invention.

[0027] Figure 6 The figure shows a device without an introducer sheath or microcatheter according to an embodiment of the present invention. Figure 5 structure.

[0028] Figure 7 A side view of a stent and stent delivery system in a fully deployed state is shown according to an embodiment of the present invention.

[0029] Figure 8 The embodiment according to the present invention is shown Figure 7 Top view of the structure.

[0030] Fig. 9 A front view of a first distal positioning disk according to an embodiment of the present invention is shown.

[0031] Fig.10 A front view of a second distal positioning disk according to another embodiment of the present invention is shown.

[0032] Fig.11 A front view of a third distal positioning disk according to another embodiment of the present invention is shown.

[0033] Fig.12 A front view of a fourth distal positioning disk according to another embodiment of the present invention is shown.

[0034] Fig.13 A bracket according to an embodiment of the present invention is shown.

[0035] Detailed description

[0036] In the description herein, certain specific details are set forth in order to provide a thorough understanding of various embodiments of the present invention. However, those skilled in the art will appreciate that the present invention can be implemented at a more general level without one or more of these details. In other cases, well-known structures are not shown or described in detail to avoid unnecessarily obscuring the description of various embodiments of the present invention.

[0037] Any reference in this specification to "one embodiment," "an embodiment," "an example embodiment," "an illustrated embodiment," "a specific embodiment," etc. means that a particular feature, structure, or characteristic described in conjunction with the embodiment is included in at least one embodiment. Thus, any appearance of the terms "in one embodiment," "in an embodiment," "in an example embodiment," "in the illustrated embodiment," "in this specific embodiment," etc. in this specification does not necessarily refer to one embodiment or the same embodiment. Furthermore, the particular features, structures, or characteristics of different embodiments may be combined in any suitable manner to form one or more other embodiments.

[0038] Unless the context clearly indicates or requires otherwise, the term "or" used in this disclosure is non-exclusive. In addition, unless the context clearly indicates or requires otherwise, the term "group" is intended to mean one or more. For example, the phrase "a group of objects" refers to one or more objects.

[0039] In the following description, the phrase "at least" is sometimes used or can be used in this article to emphasize that other elements may exist in addition to the elements clearly listed. However, unless the context clearly states otherwise (such as using the word "only") or requires, the phrase "at least" is not used in this article to still include the possibility that other elements may exist in addition to the elements clearly listed. For example, the phrase "at least includes A" includes A and may also include one or more other additional elements in addition to A. Similarly, the phrase "including A" includes A and may also include one or more other additional elements in addition to A. However, the phrase "only includes A" only includes A. Similarly, the phrase "at least set to A" includes performing the setting of A and may also include one or more other additional operations in addition to A. Similarly, the phrase "set to A" includes performing the setting of A and may also include one or more other additional operations in addition to A. However, the phrase "only set to A" means only performing the setting of A.

[0040] The word "device", the word "machine", the word "system", and the phrase "device system" are all intended to include one or more physical devices or sub-devices (e.g., parts of a device) that interact to achieve one or more functions, whether these devices or sub-devices are located in the same housing or in different housings. However, according to various embodiments, it can be expressly specified that the device or machine or device system is completely located in the same housing to exclude embodiments in which the corresponding device, machine, system, or device system spans different housings. In some embodiments, the term "device" can be equivalently referred to as a "device system".

[0041] Figure 1A stent delivery system according to some embodiments of the present invention is shown. The stent delivery system includes a distal positioning disc 100 having four (4) distal positioning disc slots 101 mounted to the distal end of a push wire 103. The stent delivery system also includes a proximal positioning disc 102 mounted on the push wire 103 proximal to the distal positioning disc 100. In some embodiments of the present invention, the push wire 103 terminates in a push wire sphere 104 to produce a flatter surface geometry and reduce the risk of damaging the patient's blood vessels during surgery. In some embodiments of the present invention, the push wire 103 can be a tapered wire. In some embodiments of the present invention, the push wire 103 can be a coil or a combination of a wire and a coil to improve the pushing ability of the stent delivery system. In some embodiments of the present invention, the distal positioning disc 100 includes fewer or more distal retaining slots 101, such as Figure 9-12 as shown to accommodate alternative bracket designs or to provide additional holding force.

[0042] Figure 2 and Figure 3 A stent delivery system is shown loaded with a self-expanding stent 105 according to some embodiments of the present invention. Figure 2 Depicted is a side view of a stent and stent delivery system in an undeployed state with the stent engaged within the delivery system locking mechanism (proximal and distal detents) according to one embodiment of the present invention. Figure 3 Depicted is a top view of a stent and stent delivery system in an undeployed state with the stent engaged within the delivery system locking mechanism (proximal and distal detents) according to one embodiment of the present invention.

[0043] The self-expanding stent 105 includes a plurality of interconnected metal segments forming a mesh tube. In some embodiments, the interconnected metal segments of the self-expanding stent 105 are formed of a superelastic metal material, which allows the self-expanding stent 105 to expand without an externally applied force (e.g., a balloon catheter). Figure 2 and Figure 3 1 , the self-expanding stent 105 is in an undeployed, crimped or covered configuration, the self-expanding stent 105 is fully engaged in the distal positioning disc slot 101, and the entire self-expanding stent 105 is covered by the introducer sheath or microcatheter 106. In some embodiments, the width of the distal positioning disc slot 101 is slightly larger than the width of the proximal end of the self-expanding stent 105. The difference in the size of the distal positioning disc slot 101 and the width of the proximal end of the self-expanding stent 105 allows the proximal end of the self-expanding stent 105 to be located inside the distal positioning disc slot 101. In some embodiments of the present invention, the distal positioning disc 100 includes four (4) distal positioning disc slots 101, which provide passages for an equal number of struts 109 of the self-expanding stent 105. In some alternative embodiments of the present invention, the distal positioning disc 100 includes a different number of distal positioning disc slots 101 to accommodate alternative stent designs with different numbers of struts 109.

[0044] Figure 4 A side view of a stent and stent delivery system in an undeployed state is depicted, wherein the stent and stent delivery system are contained within a tube, such as an introducer sheath or microcatheter 106 , according to one embodiment of the present invention. Figure 4 Shows the Figure 2 The same stent construction, but including a microcatheter 106 or an introducer sheath. In some embodiments of the present invention, prior to use, the stent delivery system and the self-expanding stent 105 can be loaded into a guide sheath for ease of packaging and shipping. In some embodiments of the present invention, the guide sheath can be constructed of a smooth plastic material that allows the stent delivery system and the self-expanding stent 105 to be advanced along the inner diameter of the guide sheath. In some embodiments of the present invention, the inner diameter of the guide sheath is at least equal to the maximum diameter of the distal positioning disk 100 and the proximal positioning disk 102, but not greater than the sum of the maximum diameter of the distal positioning disk 100 and the thickness of the proximal struts 109 of the self-expanding stent 105. As long as the inner diameter of the guide sheath meets the above specifications, the proximal end of the self-expanding stent 105 will remain engaged in the distal positioning disk slot 101.

[0045] Procedurally, in these embodiments where the stent 105 is packaged in an introducer sheath, the stent delivery system and the self-expanding stent 105 are advanced from the introducer sheath to the microcatheter 106, which is used as an in situ delivery attachment to allow the stent delivery system and the self-expanding stent 105 to reach the target treatment location. In some embodiments of the present invention, the inner diameter of the microcatheter 106 is at least equal to the maximum diameter of the distal positioning disk 100 and the proximal positioning disk 102, but not greater than the sum of the maximum diameter of the distal positioning disk 100 and the thickness of the proximal struts 109 of the self-expanding stent 105. As long as the inner diameter of the microcatheter 106 meets the above specifications, the proximal end of the self-expanding stent 105 will remain engaged in the distal positioning disk slot 101. In some embodiments, the self-expanding stent 105 can be packaged in the microcatheter 106 instead of the introducer sheath.

[0046] When the stent delivery system and the self-expanding stent 105 are advanced through the microcatheter 106 and reach the target treatment location, the interventionalist will deploy the stent. The interventionalist will determine when it is appropriate to deploy the self-expanding stent 105 by using fluoroscopic imaging. In some embodiments of the present invention, the self-expanding stent 105 includes one or more elements 110 visible under fluoroscopy. In some embodiments of the present invention, the distal positioning disk 100 and the proximal positioning disk 102 include one or more elements 110 visible under fluoroscopy. In some embodiments of the present invention, the stent delivery system includes elements visible under fluoroscopy. Deployment of the self-expanding stent 105 involves unsheathing the self-expanding stent 105. Unsheathing is accomplished by withdrawing the introducer sheath or microcatheter 106 while not moving the self-expanding stent 105, thereby exposing the self-expanding stent 105 from beneath the introducer sheath or microcatheter 106. By unsheathing the self-expanding stent 105, the diameter of the self-expanding stent 105 increases until its intended diameter is reached. When the interventionalist is confident in the position of the stent delivery system and the self-expanding stent 105 relative to the intended treatment site, the interventionalist will fully withdraw the microcatheter 106 to expose the entirety of the self-expanding stent 105 starting from the distal end of the self-expanding stent 105. As the microcatheter 106 is withdrawn, the diameter of the self-expanding stent 105 will increase. However, the self-expanding stent 105 will remain engaged in the distal positioning disc slot 101 until the proximal end of the self-expanding stent 105 is unsheathed.

[0047] As the microcatheter 106 is withdrawn, the self-expanding stent 105 enters a partially deployed state. Figure 5 and Figure 6 When in this partially deployed state, the proximal end of the self-expanding stent 105 remains engaged within the distal positioning disc 100 and the proximal positioning disc 102. In some embodiments of the present invention, the engagement force of the self-expanding stent 105 to the proximal end of the self-expanding stent 105 in the partially deployed state is enhanced due to the stent frame radial angle 107 generated by the partial deployment, which further prevents the proximal end of the self-expanding stent 105 from being disengaged in the distal positioning disc groove 101 by applying additional force to the distal positioning disc groove 101.

[0048] During the partial deployment phase of the procedure, the interventionalist may choose to recapture or re-sheath the self-expanding stent 105 by advancing the microcatheter 106 to the distal portion of the stent. The self-expanding stent 105 can be recaptured as long as the proximal end of the self-expanding stent 105 remains engaged with the distal positioning disk 100 and the proximal positioning disk 102. The interventionalist may do this to reposition the stent if the initial deployment position does not meet the treatment requirements.

[0049] Once the interventional physician confirms the correct position of the self-expanding stent 105 by partially deploying it, the self-expanding stent 105 is fully deployed by completely withdrawing the microcatheter 106, thereby exposing the proximal positioning disk 102 and the most proximal end of the self-expanding stent 105. Figure 7 and Figure 8 shown. Figure 7 A side view of a stent and stent delivery system in a fully deployed state is depicted, wherein the microcatheter 106 has been fully retracted to expose the proximal positioning disk 102 and the proximal end of the stent 105, and wherein the stent 105 has been fully deployed, according to one embodiment of the present invention. Figure 8 Shows Figure 7 Therefore, Figure 8 The stent and stent delivery system are depicted in a fully deployed state, wherein the microcatheter 106 has been fully retracted to expose the proximal positioning disk 102 and the proximal end of the stent 105, thereby enabling the stent 105 to open to its intended diameter. Figure 8 Also depicted is the deployment angle of the proximal stent apex according to one embodiment of the present invention.

[0050] The push wire 103 and the corresponding stent delivery system can then be completely removed from the patient's body along with the microcatheter 106, while the self-expanding stent 105 remains in the target vessel as a permanent implant. When fully deployed, the self-expanding stent 105 can support the target vessel to treat vascular disease, or support auxiliary devices for more complex treatments.

[0051] In some embodiments of the present invention, the proximal end of the self-expanding stent 105 is laser cut into an open geometry with stent frame corners 108, such as Figure 8 As shown. The stent frame apex angle 108 is large enough in the deployed configuration so that when in the undeployed or crimped configuration, the proximal end of the self-expanding stent 105 is at the stent frame radial angle 107, which can increase the engagement force of the self-expanding stent 105 in the distal positioning disk 100. This feature becomes increasingly important during the process of the stent delivery system and the self-expanding stent 105 being transferred from the introducer sheath to the microcatheter 106, because the difference in the inner diameter of the introducer sheath and the inner diameter of the microcatheter 106 may cause the self-expanding stent to disengage from the distal positioning disk. In some embodiments of the present invention, the stent frame apex angle 108 provides additional outward force on the distal positioning disk 100 in the undeployed state, thereby further increasing the retention force of the stent in the delivery system locking mechanism. In some embodiments of the present invention, when the microcatheter 106 is withdrawn beyond the proximal end of the self-expanding stent 105, the stent frame apex angle 108 promotes the release of the self-expanding stent 105. In this embodiment, when the compressive force applied by the microcatheter 106 is removed, the stent frame apex 108 is used to force the proximal end of the stent 105 to disengage from the delivery system locking mechanism.

[0052] In some embodiments of the present invention, the distal positioning disc 100 and the proximal positioning disc 102 are spaced apart by a sufficient amount to allow the proximal end of the self-expanding stent 105 to achieve the previously described stent frame radial angle 107. In another embodiment of the present invention, the proximal positioning disc 102 provides additional stent retention force when the device is advanced within the microcatheter 106. When the stent 105 is subjected to compressive forces caused by advancement through the microcatheter 106, the proximal positioning disc 102 will further promote the stent frame radial angle 107, further increasing the stent retention force, especially at critical moments such as transfer from the introducer sheath to the microcatheter 106.

[0053] Figure 9-12 Depicted are front views of various distal positioning disks 100 according to different embodiments of the present invention. Fig. 9 FIG. 1 is a front view of a first distal positioning disc according to an embodiment of the present invention, showing the distal positioning disc grooves that cooperate with the proximal stent struts 109 of the previous figures. Fig. 9 In the illustrated embodiment, the bracket 105 has four (4) posts 109 that engage with the four (4) slots 101 of the positioning plate 100 .

[0054] Fig.10 A front view of a second distal positioning disc according to another embodiment of the present invention is shown, which is located in a separate embodiment of the present invention, wherein only two (2) slots 101 are used for the stent delivery system locking mechanism. Fig.10 In the illustrated embodiment, the bracket 105 has two (2) posts 109 that engage with the two (2) slots 101 of the positioning plate 100 .

[0055] Fig.11 A front view of a third distal positioning disk according to another embodiment of the present invention is shown, wherein there are eight (8) slots 101 for the stent delivery system locking mechanism. Fig.11 In the illustrated embodiment, the bracket 105 has eight (8) posts 109 that engage with the eight (8) slots 101 of the positioning plate 100 .

[0056] Fig.12 A front view of a fourth distal positioning disk according to another embodiment of the present invention is shown, wherein there are twelve (12) slots 101 for a stent delivery system locking mechanism. Fig.12 In the illustrated embodiment, the bracket 105 has twelve (12) posts 109 that engage with the twelve (12) slots 101 of the positioning plate 100 .

[0057] In some embodiments of the present invention, the stent device includes a stent 105 and a stent delivery system. Fig.13As shown in the exemplary embodiment of the present invention, the stent 105 includes a cylindrical portion forming a stent framework having an outer mesh network of multiple interconnected segments, and the stent framework is configured to apply radial force to the inner wall of the blood vessel. The stent delivery system includes a locking mechanism and a push wire 103, and the locking mechanism is configured to engage with the proximal end of the stent framework when it is encased in a sheath or microcatheter 106. The locking mechanism includes a proximal positioning disc 102 and a distal positioning disc 100, and the distal positioning disc 100 has a plurality of grooves 101, and the grooves are configured to engage with an equal number of struts 109 formed on the proximal end of the stent 105.

[0058] In some embodiments of the present invention, the locking mechanism of the stent delivery system is further configured to engage with the plurality of struts 109 of the stent 105 when the stent 105 is in the partially deployed state to allow the stent 105 to be retracted to the undeployed state.

[0059] In some embodiments of the present invention, the distance between the position of the distal positioning disc 100 and the position of the proximal positioning disc 102 corresponds to the length and radius of the proximal apex of the stent framework.

[0060] In some embodiments of the present invention, the size of each of the plurality of slots 101 of the distal positioning plate is larger than the size of each of the plurality of struts 109 of the stent 105 to allow the proximal end of the stent frame 105 to be located within the plurality of slots 101 .

[0061] In some embodiments of the present invention, the locking mechanism of the stent delivery system is further configured to disengage from the plurality of struts 109 of the stent 105 when the stent 105 is in a fully deployed state to allow the stent 105 to be released in situ.

[0062] In some embodiments of the present invention, the proximal end of the stent framework has an open geometry that allows the angle on the proximal vertex to be larger in the fully expanded state than in the undeployed state. In some embodiments of the present invention, the proximal end of the stent framework includes two parallel struts 109 that are connected by arcuate ends when in the curled state. In some embodiments of the present invention, the angle of the proximal vertex on the proximal end of the stent framework is large enough in the expanded state to cause the proximal end of the stent 105 to tilt radially inward toward the central axis of the cylinder in the undeployed state.

[0063] In some embodiments of the present invention, the support 105 further comprises at least one fluorescent element 110 visible under fluorescent imaging. In some embodiments of the present invention, at least one of the distal positioning disk 100 or the proximal positioning disk 102 comprises at least one fluorescent element 110 visible under fluorescent imaging.

[0064] It should be understood that the present invention is not limited to the above-described embodiments, which are for illustrative purposes only. Subsets or combinations of the various embodiments described above provide further embodiments of the present invention.

[0065] These and other changes may be made to the present invention in light of the above detailed description and still fall within the scope of the present invention. In general, in the following claims, the terms used should not be interpreted as limiting the present invention to the specific embodiments disclosed in the specification. Therefore, the present invention is not limited by the present disclosure, but its scope is determined entirely by the appended claims.

Claims

1. A support device, comprising: a stent comprising a cylindrical portion forming a stent framework having an outer lattice network of a plurality of interconnected segments, the stent framework being configured to apply a radial force to an inner wall of a blood vessel; and A stent delivery system comprising a locking mechanism and a push wire, wherein the locking mechanism is configured to engage with a proximal end of a stent frame when encased in a sheath, The locking mechanism comprises a proximal positioning plate and a distal positioning plate, wherein the distal positioning plate has a plurality of grooves, and the grooves are configured to engage with an equal number of struts formed on the proximal end of the stent.

2. The device according to claim 1, wherein the locking mechanism of the stent delivery system is further configured to engage with a plurality of struts of the stent when the stent is in a partially deployed state to allow the stent to retract to a non-deployed state.

3. The device according to claim 1, wherein: The distance between the position of the distal positioning disc and the position of the proximal positioning disc corresponds to the length and radius of the proximal apex of the stent framework.

4. The device of claim 1, wherein the size of each of the plurality of slots of the distal positioning plate is larger than the size of each of the plurality of struts of the stent to allow the proximal end of the stent frame to be positioned within the plurality of slots.

5. The device according to claim 1, wherein the locking mechanism of the stent delivery system is further configured to disengage from the plurality of struts of the stent when the stent is in a fully deployed state to allow the stent to be released in situ.

6. The device of claim 1, wherein the proximal end of the stent framework has an open geometry that allows the angle at the proximal end apex to be greater in the fully deployed state than in the undeployed state.

7. The device of claim 6, wherein the proximal end of the stent framework comprises two parallel struts connected by arcuate ends when in the crimped state.

8. The device of claim 6, wherein the angle of the proximal apex on the proximal end of the stent framework in the expanded state is sufficiently large to cause the proximal end of the stent to tilt radially inward toward the central axis of the cylinder in the undeployed state.

9. The device of claim 1, wherein the support further comprises at least one fluorescent element visible under fluorescent imaging.

10. The device of claim 1, wherein at least one of the distal positioning disk or the proximal positioning disk comprises at least one fluorescent element visible under fluoroscopic imaging.

Images