Flexible Features for Embolic Implant Deployment - Patent application

Abstract

Various systems and methods are disclosed for deploying an implantable medical device at a target location in a body vessel. The delivery system can include a tubular body defining a longitudinal axis. The tubular body can include a lumen extending therethrough, a sidewall surrounding the lumen, and a feature formed from the sidewall. The feature can include an aperture. A pull wire can extend through the lumen. The delivery system can include an implantable medical device including a locking portion. The locking portion can include an opening. The feature can be positioned within the opening of the locking portion. A distal end of the pull wire can pass through the aperture in the feature to secure the implantable medical device to the delivery system.

Description

[Technical field]

[0001] The present invention relates to aneurysm treatment devices, and more particularly to an improved delivery system for embolic implants. [Background technology]

[0002] Numerous intravascular implant devices are known in the art. Many are mechanically deployed via a system combining one or more catheters and wires for delivery. Examples of implants that can be mechanically delivered include embolic elements, stents, grafts, drug delivery implants, flow diverters, filters, stimulation leads, sensing leads, or other implantable structures delivered through a microcatheter. Some obstetric and gastrointestinal implants can also be implanted via a similar system combining one or more catheters and wires. Devices that can be released or deployed by mechanical means vary greatly in design, but can use similar delivery catheter and wire systems. Many such catheter-based delivery systems include a wire to hold the implant within the catheter until the time of release of the device. These systems are then actuated by retracting or pulling the wire relative to the catheter. Such a wire is referred to herein as a "pull wire." Many such catheter-based delivery systems also implement a "loop wire" that has an end attached to the tubular body of the catheter, forming a loop in which the pull wire can be positioned to hold the implant within the catheter.

[0003] One problem with current catheter-based delivery systems is the complexity of attaching the loop wire to the tubular body of the catheter. The complexity of forming the loop wire and attaching it to the catheter delivery system reduces the reliability of the delivery system and increases the likelihood of the implant becoming prematurely detached from the catheter system. Summary of the Invention [Problem to be solved by the invention]

[0004] Thus, there is a need for an improved implant delivery system that does not utilize loop wires to retain the implant on the catheter system.The present disclosure is directed to this and other considerations. [Means for solving the problem]

[0005] Various systems and methods are disclosed for deploying an implantable medical device at a target location in a body vessel. The delivery system can include a tubular body defining a longitudinal axis. The tubular body can include a lumen extending therethrough, a sidewall surrounding the lumen, and a feature formed from the sidewall. The feature can include an aperture. A pull wire can extend through the lumen. The delivery system can include an implantable medical device including a locking portion. The locking portion can include an opening. The feature can be positioned within the opening of the locking portion. A distal end of the pull wire can pass through the aperture of the feature to secure the implantable medical device to the delivery system.

[0006] In one aspect, a delivery system for deploying an implantable medical device at a target location in a body vessel is disclosed. The delivery system can include a tubular body defining a longitudinal axis. The tubular body can include a lumen extending therethrough, a sidewall surrounding the lumen, and a feature formed from the sidewall. The feature can include an aperture through the feature. The system can include a pull wire extending through the lumen. The delivery system can include an implantable medical device, the implantable medical device can include a locking portion having an opening. The feature formed from the sidewall can be positioned within the opening of the locking portion of the implantable medical device. A distal end of the pull wire can pass through the aperture of the feature to secure the implantable medical device to the delivery system.

[0007] In some embodiments, the features may include tab shapes cut into the sidewall and bent into a folded configuration. The features may be biased toward the longitudinal axis of the tubular body to secure the implantable medical device to a delivery system. In some embodiments, the features may be laser cut from the sidewall.

[0008] In some embodiments, the features can be configured to return to an unfolded configuration when the distal end of the pull wire is removed from the aperture, thereby deploying the implantable medical device at a target location in a body vessel.

[0009] In some embodiments, the feature is configured to impart a resilient force to the implantable medical device in response to the feature returning from the collapsed configuration to the uncollapsed configuration.

[0010] In some embodiments, the features may be formed from a shape memory material.

[0011] In some embodiments, the pull wires can be coated with polytetrafluoroethylene (PTFE).

[0012] In some embodiments, the features may be constructed from a resilient material.

[0013] In some embodiments, the distal end of the pull wire can be positioned through an aperture in the feature such that the distal end of the pull wire interferes with the locking portion, thereby securing the implantable medical device to the delivery system.

[0014] In some embodiments, when the pull wire is pulled proximally, the distal end of the pull wire is withdrawn through an aperture in the feature, releasing the implantable medical device from the delivery system.

[0015] In some embodiments, when the distal end of the pull wire is withdrawn from the aperture in the feature, the distal end of the pull wire no longer interferes with the locking portion, thereby facilitating release of the implantable medical device from the delivery system.

[0016] In another aspect, a method is disclosed. The method can include providing a tubular body including a lumen extending therethrough and a sidewall surrounding the lumen. The tubular body can define a longitudinal axis. The method can include forming a feature in the sidewall of the tubular body. The feature can include an aperture. The feature can be bent from an unfolded configuration to a folded configuration such that the feature is biased toward the longitudinal axis of the tubular body. A pull wire can extend through the lumen. A locking portion of the implantable medical device can be positioned over the feature in the folded configuration. A distal end of the pull wire can be positioned through the aperture in the feature, thereby securing the implantable medical device to the tubular body. The implantable medical device can be positioned near a target location in a body vessel. The pull wire can be translated proximally, thereby deploying the implantable medical device at a target location in a body vessel.

[0017] In some embodiments, the feature can include a tab shape cut into the side wall and bent into a folded configuration, hi some embodiments, forming the feature can include laser cutting the feature into the side wall.

[0018] In some embodiments, deploying the implantable medical device at a target location in a body vessel can further include the feature returning from the collapsed configuration to an uncollapsed configuration.

[0019] In some embodiments, the return of the features to the unfolded configuration can impart a resilient force to the implantable medical device as it is deployed to a target location in a body vasculature.

[0020] In some embodiments, the method can include coating the pull wire with polytetrafluoroethylene (PTFE).

[0021] In some embodiments, when the pull wire is pulled proximally, the distal end of the pull wire is withdrawn through an aperture in the feature, releasing the implantable medical device from the tubular body.

[0022] In some embodiments, when the distal end of the pull wire is withdrawn from the aperture in the feature, the distal end of the pull wire no longer interferes with the locking portion of the implantable medical device, thereby facilitating release of the implantable medical device from the tubular body.

[0023] In some embodiments, the features may be formed from a shape memory material. [Brief description of the drawings]

[0024] The above and further aspects of the present invention will be further discussed with reference to the following description in conjunction with the accompanying drawings, in which like numerals indicate like structural elements and features in the various drawings. The drawings are not necessarily to scale, and instead the focus is on illustrating the principles of the invention. The figures depict one or more implementations of the apparatus of the present invention by way of example only, and not by way of limitation. [Figure 1] 1 is an illustration of a delivery system and implant according to an embodiment of the present invention. [Figure 2A] 1 illustrates a sequence of steps for securing an implantable medical device to a feature of a delivery system according to an aspect of the present invention. [Figure 2B] 1 illustrates a sequence of steps for securing an implantable medical device to a feature of a delivery system according to an aspect of the present invention. [Figure 2C] 1 illustrates a sequence of steps for securing an implantable medical device to a feature of a delivery system according to an aspect of the present invention. [Figure 2D]1 illustrates a sequence of steps for securing an implantable medical device to a feature of a delivery system according to an aspect of the present invention. [Figure 3A] 1 illustrates a sequence of steps for releasing an implantable medical device from a feature of a delivery system, according to an aspect of the present invention. [Figure 3B] 1 illustrates a sequence of steps for releasing an implantable medical device from a feature of a delivery system, according to an aspect of the present invention. [Figure 3C] 1 illustrates a sequence of steps for releasing an implantable medical device from a feature of a delivery system, according to an aspect of the present invention. [Figure 4] 1 is an illustration of an implantable medical device positioned within an aneurysm, according to an aspect of the present invention. [Figure 5A] 1 illustrates a sequence of steps for releasing an implantable medical device from a delivery member according to an aspect of the present invention. [Figure 5B] 1 illustrates a sequence of steps for releasing an implantable medical device from a delivery member according to an aspect of the present invention. [Figure 5C] 1 illustrates a sequence of steps for releasing an implantable medical device from a delivery member according to an aspect of the present invention. [Figure 5D] 1 illustrates a sequence of steps for releasing an implantable medical device from a delivery member according to an aspect of the present invention. [Figure 6] 1 is a flow chart of an exemplary method of using a delivery system, according to an aspect of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0025] The following description of specific examples of the present invention should not be used to limit the scope of the present invention. The drawings, which are not necessarily to scale, depict selected embodiments and are not intended to limit the scope of the present invention. The detailed description illustrates the principles of the present invention by way of example, not by way of limitation. Other examples, features, aspects, embodiments and advantages of the present invention will become apparent to those skilled in the art from the following description, which is, by way of example, one of the best modes contemplated for carrying out the present invention. As will be appreciated, the present invention is capable of other different or equivalent aspects, all without departing from the present invention. The drawings and description should therefore be regarded as illustrative in nature, and not restrictive.

[0026] Any one or more of the teachings, expressions, variations, examples, etc. described herein may be combined with any one or more of the other teachings, expressions, variations, examples, etc. described herein. Thus, the teachings, expressions, variations, examples, etc. described below should not be considered in isolation from one another. In light of the teachings herein, various suitable methods that may be combined with the teachings herein will be readily apparent to those skilled in the art. Such modifications and variations are intended to be included within the scope of the claims.

[0027] As used herein, the term "about" or "approximately" with respect to any numerical value or range indicates a suitable dimensional tolerance that allows a portion or collection of components to function for the intended purpose described herein. More specifically, "about" or "approximately" may refer to a range of values ​​of ±10% of the recited value, e.g., "about 90%" may refer to a range of values ​​of 81% to 99%. Additionally, as used herein, the terms "patient," "host," "user," and "subject" refer to any human or animal subject, and while use of the invention in human patients represents a preferred embodiment, it is not intended to limit the system or method to human use.

[0028] Referring to FIG. 1, FIG. 1 illustrates an exemplary delivery system 10 for deploying an implantable medical device 12 at a target location in a vasculature of a body. The delivery system 10 can include a tubular body 90 having a lumen 508 extending therethrough. The tubular body can define a longitudinal axis LL. The lumen 508 can be surrounded by a sidewall 96 of the tubular body 90. The feature 150 can be located near a distal end 94 of the tubular body 90. The feature 150 can be formed from the sidewall 96 of the tubular body 90. According to some embodiments, the feature 150 can be in the shape of a tab cut into the sidewall 96. According to some embodiments, the feature can be laser cut from the sidewall. The feature 150 can have an unfolded configuration at rest and can automatically or elastically return from a folded configuration to an unfolded configuration unless otherwise restrained. According to some embodiments, the feature 150 can be constructed from an elastic material or a shape memory alloy, such as Nitinol, to allow the feature 150 to elastically return from a folded configuration to an unfolded configuration. As shown in FIG. 1 , the feature 150 can be in a folded configuration and positioned through the opening 20 of the locking portion 18 of the implantable medical device 12. The folded configuration of the feature 150 can be characterized in that the feature 150 is biased toward the longitudinal axis LL of the tubular body. According to some embodiments, the feature 150 can be constructed from a shape memory material, such as, for example, Nitinol. As shown, the implantable medical device 12 is located near the distal end 94 of the tubular body 90. The pull wire 140 can extend through a lumen 508 of the tubular body 90. The distal end 144 of the pull wire 140 can be positioned through the aperture 152 of the feature 10 after the feature 150 is positioned through the opening 20 of the locking portion 18. Once the distal end 144 of the pull wire 140 is positioned through the aperture 152 of the feature 150, the implantable medical device 12 is secured to the delivery system 10. The pull wire 140 can be constructed from any suitable material, for example, the pull wire 140 can be constructed from stainless steel or a shape memory material such as Nitinol.According to some embodiments, the pullwires 140 may be coated with a polymer such as polytetrafluoroethylene (PTFE).

[0029] 2A-2D illustrate a sequence of steps for securing an implantable medical device to a feature of a delivery system, according to an embodiment of the present invention. FIG. 2A shows feature 150 as it is molded from sidewall 96 of tubular body 90. Feature 150 may include aperture 152. As shown in FIG. 2A, feature 150 is in an unfolded configuration 154. FIG. 2B shows feature 150 folded toward longitudinal axis LL and locking portion 18 of implantable medical device 12 positioned within lumen 508. FIG. 2C shows feature 150 in a folded configuration 156, where locking portion 18 of implantable medical device 12 (not shown) is positioned over feature 150. As shown, locking portion 18 is positioned over feature 150 such that a portion of feature 150, including aperture 152, is positioned through locking portion 18. 2D , distal end 144 of pullwire 140 is positioned through aperture 152 after feature 150 has been positioned through anchoring portion 18 of implantable medical device 12. In this configuration, implantable medical device 12 is now secured to delivery system 10.

[0030] 3A-3C illustrate a sequence of steps for releasing an implantable medical device from a feature of a delivery system according to an embodiment of the present invention. In FIG. 3A, the implantable medical device 12 (not shown) is secured to the delivery system 10 via the interface of the pull wire 140 with the feature 150 and the locking portion 18. In FIG. 3B, the distal end 144 of the pull wire 140 has been withdrawn from the aperture 152 of the feature 150. The feature 150 is now free to resiliently move from the folded configuration 156 to the unfolded configuration 154. FIG. 3C shows the distal end 144 of the pull wire 140 just after exiting the aperture 152 of the feature 150. The arrow indicates the feature 150 resiliently moving from the folded configuration 156 to the unfolded configuration 154. Movement of feature 150 may thereby allow anchoring portion 18 of the implantable medical device to disengage from delivery system 10. Additionally, movement of feature 150 may impart a resilient force E that urges implantable medical device 18 toward the treatment site.

[0031] 4 is an illustration of an embolic implant 12 delivered through a catheter 250 and positioned within an aneurysm A of a blood vessel BV. The implants may loop and bend within the aneurysm sac to form a thrombotic mass. The implants may loop back on themselves and / or loop next to other implants. As the aneurysm A becomes increasingly crowded, overlapping portions of the implants 12 may be pushed into one another.

[0032] 5A-5D illustrate a timeline of steps for releasing the embolic implant 12 from the delivery system 10. The delivery system 10 may be configured as illustrated in the previous figures and as otherwise described herein. FIG. 5A illustrates an engagement system including a pull wire 140 and a feature 150 locked to the locking portion 18 of the medical device 12. The feature 150 may be in a folded configuration 156, and the feature may be positioned through an opening 20 in the locking portion 18 of the implantable medical device 12. Once the distal end 144 of the pull wire 140 is threaded through the aperture 152 of the feature 150, the implantable medical device 12 is now secured. FIG. 5B illustrates the pull wire 140 being pulled proximally to initiate the release sequence of the implantable medical device 12. FIG. 5C illustrates the moment when the pull wire 140 is pulled without the feature 150 as the pull wire distal end 144 exits the aperture 152. The feature 150 moves from the folded configuration 156 to the unfolded configuration 154 and exits the opening 20 of the locking portion 18. As shown, there is now nothing holding the medical device 12 to the delivery system 10. FIG. 5D illustrates the end of the release sequence, where the feature 150 has moved from the folded configuration 156 back to the unfolded configuration 154. The feature 150 applies a resilient force E to the implantable medical device 12, "pushing" the implantable medical device 12 apart to ensure clean separation and delivery of the implantable medical device 12.

[0033] 6 is a flow chart of an exemplary method of using a delivery system, according to an embodiment of the present invention. At block 604, the method may include providing a tubular body 90. The tubular body 90 includes a lumen 508 extending therethrough. The tubular body may define a longitudinal axis LL. The lumen 508 may be surrounded by a sidewall 96.

[0034] At block 608, the method may include forming a feature 150 in the sidewall 96 of the tubular body. The feature may include an aperture 152. At block 612, the method may include bending the feature 150 from an unfolded configuration 154 to a folded configuration 156. When bent, the feature 150 may be biased toward the longitudinal axis LL of the tubular body 90.

[0035] At block 616, the pull wire 140 may extend through the lumen 508. At block 620, the method may include positioning the locking portion 18 of the implantable medical device 12 over the feature 150 while the feature 150 is in the folded configuration 156. At block 624, the method may include positioning the distal end 144 of the pull wire 140 through the aperture 152 of the feature 150. Once the distal end 144 of the pull wire 140 is positioned through the aperture 152, the implantable medical device may be secured to the tubular body 90 of the delivery system 10.

[0036] At block 628, the method may include positioning the implantable medical device 12 proximate the target location in the body vessel. At block 632, the method may include translating the pullwire 140 proximally, thereby deploying the implantable medical device 12 at the target location in the body vessel.

[0037] In some embodiments, the features may be formed as tab shapes cut into the sidewall 96 and bent into the folded configuration 156 .

[0038] In some embodiments, forming the feature can further include laser cutting the feature 150 in the sidewall 96 .

[0039] In some embodiments, deploying the implantable medical device 12 to a target location in a body vessel can further include the feature reverting from the collapsed configuration 156 to the uncollapsed configuration 154.

[0040] In some embodiments, the return of feature 150 to unfolded configuration 154 can impart an elastic force (E) to the implantable medical device 12 as the implantable medical device 12 is deployed to a target location in a vasculature of the body.

[0041] In some embodiments, the method can include coating the pullwire 140 with PTFE.

[0042] In some embodiments, when the pull wire 140 is pulled proximally, the distal end 144 of the pull wire 140 is withdrawn from the aperture 152 of the feature, releasing the implantable medical device from the tubular body 90 .

[0043] In some embodiments, when the distal end 144 of the pullwire 140 is withdrawn from the aperture 152 of the feature 150, the distal end 144 of the pullwire 140 no longer interferes with the locking portion 18, thereby facilitating release of the implantable medical device from the tubular body 90. In some embodiments, the feature 150 can be formed from a shape memory material.

[0044] The descriptions contained herein are examples of embodiments of the invention and are not intended to limit the scope of the invention in any way. As described herein, the invention contemplates many variations and modifications of the implantation system and related methods, including alternative geometries of system components, alternative materials, additional or alternative method steps, etc. Modifications that are obvious to one of ordinary skill in the art are intended to be within the scope of the following claims.

[0045] [Embodiment] (1) A delivery system for deploying an implantable medical device at a target location in a body vasculature, comprising: A tubular body defining a longitudinal axis, a lumen extending through said tubular body; a sidewall surrounding the lumen; and a tubular body comprising a feature formed from the sidewall, the feature comprising an aperture; a pull wire extending through said lumen; a locking portion of the implantable medical device comprising an opening, the feature being positioned within the opening of the locking portion; A delivery system wherein a distal end of the pull wire passes through the aperture in the feature to secure the implantable medical device to the delivery system. (2) The delivery system of embodiment 1, wherein the feature comprises a tab shape cut into the side wall and bent into a folded configuration, the feature being biased toward the longitudinal axis of the tubular body to secure the implantable medical device to the delivery system. (3) The delivery system of claim 1, wherein the feature is laser cut from the side wall. (4) The delivery system of embodiment 2, wherein the feature is configured to return to a non-collapsed configuration when the distal end of the pull wire is removed from the aperture, thereby deploying the implantable medical device at the target location in the body vessel. (5) The delivery system of embodiment 4, wherein the feature is configured to impart a resilient force to the implantable medical device in response to the feature returning from the folded configuration to the unfolded configuration.

[0046] (6) The delivery system of embodiment 1, wherein the feature is formed from a shape memory material. (7) The delivery system of claim 1, wherein the pull wire is coated with polytetrafluoroethylene. (8) The delivery system of claim 1, wherein the feature comprises an elastic material. (9) The delivery system of embodiment 1, wherein the distal end of the pull wire is positioned through the aperture of the feature such that the distal end of the pull wire interferes with the locking portion, thereby securing the implantable medical device to the delivery system. (10) The delivery system of embodiment 1, wherein when the pull wire is pulled proximally, the distal end of the pull wire is withdrawn from the aperture in the feature, releasing the implantable medical device from the delivery system.

[0047] (11) The delivery system of embodiment 10, wherein when the distal end of the pull wire is withdrawn from the aperture of the feature, the distal end of the pull wire no longer interferes with the locking portion, thereby facilitating release of the implantable medical device from the delivery system. (12) A method comprising the steps of: providing a tubular body having a lumen extending therethrough and a sidewall surrounding said lumen, said tubular body defining a longitudinal axis; forming a feature in the sidewall of the tubular body, the feature comprising an aperture; and bending the feature from an unfolded configuration to a folded configuration such that the feature is biased toward the longitudinal axis of the tubular body; extending a pull wire through the lumen; positioning an anchoring portion of an implantable medical device over the feature in the folded configuration; positioning a distal end of the pull wire through the aperture in the feature, thereby securing the implantable medical device to the tubular body; positioning the implantable medical device proximate a target location in a body vessel; and proximally translating the pull wire, thereby deploying the implantable medical device at the target location in the body vessel. 13. The method of claim 12, wherein the feature comprises a tab shape cut into the side wall and bent into a folded configuration. 14. The method of claim 12, wherein forming the feature further comprises laser cutting the feature in the sidewall. (15) The method of claim 12, wherein deploying the implantable medical device at the target location in the body vessel further comprises the feature returning to the unfolded configuration.

[0048] (16) The method of claim 15, wherein the return of the feature to the unfolded configuration imparts a resilient force to the implantable medical device when the implantable medical device is deployed to the target location in a blood vessel of the body. 17. The method of claim 12, further comprising coating the pull wire with polytetrafluoroethylene. (18) The method of embodiment 12, wherein when the pull wire is pulled proximally, the distal end of the pull wire is withdrawn from the aperture in the feature, releasing the implantable medical device from the tubular body. (19) The method of embodiment 18, wherein when the distal end of the pull wire is withdrawn from the aperture of the feature, the distal end of the pull wire no longer interferes with the locking portion, thereby facilitating release of the implantable medical device from the tubular body. 20. The method of claim 12, wherein the feature is formed from a shape memory material.

Claims

1. 1. A delivery system for deploying an implantable medical device at a target location in a body vessel, comprising: A tubular body defining a longitudinal axis, a lumen extending through said tubular body; a sidewall surrounding the lumen; and a tubular body comprising a feature formed from the sidewall, the feature comprising an aperture; a pull wire extending through said lumen; a locking portion of the implantable medical device comprising an opening, the feature being positioned within the opening of the locking portion; A delivery system wherein a distal end of the pull wire passes through the aperture in the feature to secure the implantable medical device to the delivery system.

2. 2. The delivery system of claim 1, wherein the feature comprises a tab shape cut into the side wall and bent into a folded configuration, the feature being biased toward the longitudinal axis of the tubular body to secure the implantable medical device to the delivery system.

3. The delivery system of claim 1 , wherein the feature is laser cut from the sidewall.

4. 3. The delivery system of claim 2, wherein the feature is configured to return to an uncollapsed configuration when the distal end of the pull wire is removed from the aperture, thereby deploying the implantable medical device at the target location in the body vessel.

5. The delivery system of claim 4 , wherein the feature is configured to impart a resilient force to the implantable medical device in response to the feature returning from the collapsed configuration to the uncollapsed configuration.

6. The delivery system of claim 1 , wherein the feature is formed from a shape memory material.

7. The delivery system of claim 1 , wherein the pull wire is coated with polytetrafluoroethylene.

8. The delivery system of claim 1 , wherein the feature comprises a resilient material.

9. 2. The delivery system of claim 1, wherein the distal end of the pull wire is positioned through the aperture of the feature such that the distal end of the pull wire interferes with the locking portion, thereby securing the implantable medical device to the delivery system.

10. The delivery system of claim 1 , wherein when the pull wire is pulled proximally, the distal end of the pull wire is withdrawn from the aperture in the feature to release the implantable medical device from the delivery system.

11. The delivery system of claim 10 , wherein when the distal end of the pull wire is withdrawn from the aperture of the feature, the distal end of the pull wire no longer interferes with the locking portion, thereby facilitating release of the implantable medical device from the delivery system.

12. 1. A method comprising: providing a tubular body having a lumen extending therethrough and a sidewall surrounding said lumen, said tubular body defining a longitudinal axis; forming a feature in the sidewall of the tubular body, the feature comprising an aperture; and bending the feature from an unfolded configuration to a folded configuration such that the feature is biased toward the longitudinal axis of the tubular body; extending a pull wire through the lumen; positioning an anchoring portion of an implantable medical device over the feature in the folded configuration; positioning a distal end of the pull wire through the aperture in the feature, thereby securing the implantable medical device to the tubular body; positioning the implantable medical device proximate a target location in a body vessel; and proximally translating the pull wire, thereby deploying the implantable medical device at the target location in the body vessel.

13. The method of claim 12 , wherein the feature comprises a tab shape cut into the side wall and bent into a folded configuration.

14. The method of claim 12 , wherein forming the feature further comprises laser cutting the feature in the sidewall.

15. 13. The method of claim 12, wherein deploying the implantable medical device at the target location in the body vessel further comprises the features returning to the unfolded configuration.

16. 16. The method of claim 15, wherein the return of the features to the unfolded configuration imparts a resilient force to the implantable medical device as the implantable medical device is deployed to the target location in a vessel of the body.

17. The method of claim 12 , further comprising coating the pull wire with polytetrafluoroethylene.

18. The method of claim 12 , wherein when the pull wire is pulled proximally, the distal end of the pull wire is withdrawn from the aperture in the feature to release the implantable medical device from the tubular body.

19. 20. The method of claim 18, wherein when the distal end of the pull wire is withdrawn from the aperture in the feature, the distal end of the pull wire no longer interferes with the locking portion, thereby facilitating release of the implantable medical device from the tubular body.

20. The method of claim 12 , wherein the features are formed from a shape memory material.

Images