Patent Description:
A wide variety of intracorporeal medical devices have been developed for medical use, for example, surgical and/or intravascular use. Some of these devices include guidewires, catheters, medical device delivery systems (e.g., for stents, grafts, replacement valves, etc.), and the like. These devices are manufactured by any one of a variety of different manufacturing methods and may be used according to any one of a variety of methods. Of the known medical devices and methods, each has certain advantages and disadvantages. There is an ongoing need to provide alternative medical devices as well as alternative methods for manufacturing and/or using medical devices.

<CIT> relates to an implant and delivery system including a female coupler at a proximal end of the implant and a male coupler at a distal end of an elongate tubular delivery member. The male coupler is insertable within the female coupler and expandable under the influence of an elongate control member that is slidable within the tubular delivery member. Expansion of the male coupler locks the implant to the tubular delivery member. Withdrawal of the control member unlocks the implant from the tubular delivery member, enabling placement of the implant within a body.

<CIT> relates to devices, systems and methods for tissue approximation and repair at treatment sites. The devices, systems and methods are intended to find use in a variety of therapeutic procedures, including endovascular, minimally-invasive, and open surgical procedures, and can be used in various anatomical regions, including the abdomen, thorax, cardiovascular system, heart, intestinal tract, stomach, urinary tract, bladder, lung, and other organs, vessels, and tissues.

In a first aspect, an occlusive medical device system comprises an elongate shaft having a proximal end, a distal strain relief portion, and a lumen extending longitudinally through the elongate shaft, the elongate shaft further comprising a plurality of retaining arms extending distally from the distal strain relief portion. The occlusive medical device system comprises an occlusive medical device configured to occlude fluid flow through a vessel lumen, the occlusive medical device including a proximal mounting portion fixed to an expandable occlusive element. The occlusive medical device system comprises a release wire disposed within the lumen of the elongate shaft and axially translatable between a distal engagement position and a proximal released position. The plurality of retaining arms extend into the proximal mounting portion. The release wire is configured to engage the plurality of retaining arms in the distal engagement position, thereby urging the plurality of retaining arms radially outward into releasable engagement with the proximal mounting portion of the occlusive medical device. When the release wire is in the proximal released position, the plurality of retaining arms is deflectable radially inward to disengage from the proximal mounting portion.

The distal strain relief portion includes a plurality of micromachined or laser cuts extending at an angle to a longitudinal axis of the elongate shaft from an outer surface of the elongate shaft through to the lumen extending through the elongate shaft.

In addition or alternatively, the plurality of micromachined or laser cuts extend perpendicular to the longitudinal axis of the elongate shaft.

In addition or alternatively, the proximal mounting portion includes a plurality of apertures configured to engage the plurality of retaining arms when the release wire is in the distal engagement position.

In addition or alternatively, each of the plurality of retaining arms includes a protrusion extending radially outward from an outer surface of the retaining arm.

In addition or alternatively, each of the protrusions of the plurality of retaining arms engages one of the plurality of apertures of the proximal mounting portion when the release wire is in the distal engagement position.

In addition or alternatively, an occlusive medical device system may comprise an elongate shaft having a proximal end, a distal strain relief portion, and a lumen extending longitudinally through the elongate shaft, the elongate shaft further comprising a plurality of retaining arms extending distally from the distal strain relief portion, each retaining arm having a protrusion proximate a distal end thereof and extending radially outward from an outwardly-facing surface of the retaining arm. The occlusive medical device system may comprise an occlusive medical device configured to occlude fluid flow through a vessel lumen, the occlusive medical device including a proximal tubular mounting portion fixed to an expandable occlusive element, the proximal tubular mounting portion including a lumen extending longitudinally through the proximal tubular mounting portion and a ridge extending radially inward from an inwardly-facing surface of the proximal tubular mounting portion proximate a proximal end of the proximal tubular mounting portion. The occlusive medical device system may comprise a release wire disposed within the lumen of the elongate shaft and axially translatable between a distal engagement position and a proximal released position. The plurality of retaining arms may extend into the proximal tubular mounting portion. The release wire may be configured to engage the plurality of retaining arms in the distal engagement position, thereby urging the plurality of retaining arms radially outward such that proximal axial translation of the elongate shaft relative to the proximal tubular mounting portion is prevented. When the release wire is in the proximal released position, the plurality of retaining arms is deflectable radially inward such that proximal axial translation of the elongate shaft relative to the proximal tubular mounting portion is permitted.

In addition or alternatively, the ridge is integrally formed with the proximal tubular mounting portion.

In addition or alternatively, the ridge is formed as a part of a tubular ring fixedly attached to a proximal end of the proximal tubular mounting portion.

In addition or alternatively, the ridge defines a proximal aperture having a diameter less than a diameter of the lumen of the proximal tubular mounting portion.

In addition or alternatively, the diameter of the proximal aperture is less than a maximum outer extent of the protrusions of the plurality of retaining arms when the release wire is in the distal engagement position.

In addition or alternatively, the occlusive medical device includes a radiopaque insert disposed within the lumen of the proximal tubular mounting portion.

In addition or alternatively, the elongate shaft is axially slidable within the proximal tubular mounting portion.

In addition or alternatively, advancing the elongate shaft distally urges the distal ends of the plurality of retaining arms into contact with the radiopaque insert.

In addition or alternatively, when the release wire is in the distal engagement position, withdrawing the elongate shaft proximally urges the protrusions of the plurality of retaining arms into contact with the ridge.

In addition or alternatively, the occlusive medical device includes a lumen extending longitudinally through the proximal mounting portion and a radiopaque marker fixedly secured within a distal end of the lumen extending longitudinally through the proximal mounting portion.

In addition or alternatively, the proximal mounting portion includes a plurality of protrusions extending radially inward into the lumen extending longitudinally through the proximal mounting portion.

In addition or alternatively, each of the plurality of retaining arms includes an aperture configured to engage one of the plurality of protrusions when the release wire is in the distal engagement position.

In addition or alternatively, the occlusive medical device system may comprise a securement member having a proximal portion fixedly attached to a proximal end of the release wire and a distal portion fixedly attached to a proximal end of the elongate shaft. The securement member may be configured to prevent axial translation of the release wire relative to the elongate shaft prior to disengagement of the proximal portion of the securement member from the distal portion of the securement member and permit axial translation of the release wire relative to the elongate shaft after disengagement of the proximal portion of the securement member from the distal portion of the securement member.

While aspects of the disclosure are amenable to various modifications and alternative forms, specifics thereof have been shown by way of example in the drawings and will be described in detail. It should be understood, however, that the intention is not to limit aspects of the disclosure to the particular embodiments described.

The following description should be read with reference to the drawings, which are not necessarily to scale, wherein like reference numerals indicate like elements throughout the several views. The detailed description and drawings are intended to illustrate but not limit the claimed invention. Those skilled in the art will recognize that the various elements described and/or shown may be arranged in various combinations and configurations without departing from the scope of the disclosure. The detailed description and drawings illustrate example embodiments of the claimed invention. However, in the interest of clarity and ease of understanding, while every feature and/or element may not be shown in each drawing, the feature(s) and/or element(s) may be understood to be present regardless, unless otherwise specified.

The term "extent" may be understood to mean a greatest measurement of a stated or identified dimension. For example, "outer extent" may be understood to mean a maximum outer dimension, "radial extent" may be understood to mean a maximum radial dimension, "longitudinal extent" may be understood to mean a maximum longitudinal dimension, etc. Each instance of an "extent" may be different (e.g., axial, longitudinal, lateral, radial, circumferential, etc.) and will be apparent to the skilled person from the context of the individual usage. Generally, an "extent" may be considered a greatest possible dimension measured according to the intended usage. In some instances, an "extent" may generally be measured orthogonally within a plane and/or cross-section, but may be, as will be apparent from the particular context, measured differently - such as, but not limited to, angularly, radially, circumferentially (e.g., along an arc), etc..

Diseases and/or medical conditions that impact and/or are affected by the cardiovascular system are prevalent throughout the world. For example, some forms of arterial venous malformations (AVMs) may "feed" off of normal blood flow through the vascular system. Without being bound by theory, it is believed that it may be possible to treat, at least partially, arterial venous malformations and/or other diseases or conditions by starving them of normal, oxygen and/or nutrient-rich blood flow, thereby limiting their ability to grow and/or spread. Other examples of diseases or conditions that may benefit from vascular occlusion include, but are not limited to, bleeds, aneurysms, venous insufficiency, shutting off blood flow prior to organ resection, or preventing embolic bead reflux into branch vessels in the liver. Disclosed herein are medical devices that may be used within a portion of the cardiovascular system in order to treat and/or repair some arterial venous malformations and/or other diseases or conditions. The devices disclosed herein may also provide a number of additional desirable features and benefits as described in more detail below.

<FIG> and <FIG> illustrate an example occlusive medical device system. Certain details of various elements of the occlusive medical device system are described in greater detail below with reference to <FIG>. The occlusive medical device system may comprise a delivery sheath <NUM> having a lumen extending through the delivery sheath <NUM>. The occlusive medical device system may comprise an elongate shaft <NUM> slidably disposed within the lumen of the delivery sheath <NUM>. The elongate shaft <NUM> may include a proximal end, a distal strain relief portion <NUM> opposite the proximal end, and a lumen <NUM> extending longitudinally through the elongate shaft <NUM> along a longitudinal axis of the elongate shaft <NUM>. Additionally, the occlusive medical device system may comprise a release wire <NUM> slidably disposed within the lumen <NUM> of the elongate shaft <NUM> and axially translatable between a distal engagement position (e.g., <FIG>) and a proximal released position (e.g., <FIG>), for reasons that will become apparent. In some embodiments, a proximal portion and/or proximal end of the release wire <NUM> may be releasably secured to the proximal end of the elongate shaft <NUM>, for example, using (but not limited to) a perforated polymer joint, a dissimilar polymer joint, a frangible joint, etc. Some suitable but non-limiting materials for the delivery sheath <NUM>, the elongate shaft <NUM>, and/or the release wire <NUM>, for example metallic materials, polymer materials, composite materials, etc., are described below.

The occlusive medical device system may comprise an occlusive medical device <NUM> configured to occlude fluid and/or blood flow through a vessel lumen (e.g., an artery, etc.). The occlusive medical device <NUM> may include a proximal tubular mounting portion <NUM> fixed to, fixedly attached to, and/or integrally formed with an expandable occlusive element <NUM>. The occlusive medical device <NUM> may have and/or define a longitudinal axis extending from the proximal tubular mounting portion <NUM> through and/or along the expandable occlusive element <NUM>. In some embodiments, at least a portion of the elongate shaft <NUM> may extend into and/or releasably engage with the proximal tubular mounting portion <NUM> of the occlusive medical device <NUM>. In some embodiments, the distal strain relief portion <NUM> of the elongate shaft <NUM> may provide flexibility and/or more flexibility to the elongate shaft <NUM> adjacent the occlusive medical device <NUM>, thereby preventing kinking, breakage, etc. of the elongate shaft <NUM> and/or the release wire <NUM>. The occlusive medical device <NUM> and/or the expandable occlusive element <NUM> may be radially expandable and/or longitudinally foreshortenable from a delivery configuration (e.g., <FIG>) to an expanded configuration (e.g., <FIG>). The expandable occlusive element <NUM> may comprise a support frame <NUM> and an occlusive membrane <NUM> fixedly attached to, encapsulating, and/or surrounding at least a portion of the support frame <NUM>. Alternatively, the occlusive medical device <NUM> may be and/or include a vascular plug, an embolic coil, or other suitable occlusive medical device.

In some embodiments, the occlusive medical device <NUM> and/or the expandable occlusive element <NUM> may be disposed within a distal portion of the delivery sheath <NUM> in the delivery configuration, as seen in <FIG>. After advancing and/or navigating the occlusive medical device <NUM> to a target site or area of interest, the elongate shaft <NUM> and/or the occlusive medical device <NUM> may be advanced distally out of the delivery sheath <NUM>, and/or the delivery sheath <NUM> may be retracted proximally as the elongate shaft <NUM> and/or the occlusive medical device <NUM> is held in a fixed position, (e.g., the elongate shaft <NUM> and/or the occlusive medical device <NUM> may be translated longitudinally relative to the delivery sheath <NUM>) to expose the occlusive medical device <NUM>. In at least some embodiments, the support frame <NUM> may be formed from a self-expanding material configured to automatically expand toward and/or to the expanded configuration when unconstrained (e.g., the support frame <NUM> may be configured to shift from the delivery configuration to the expanded configuration), as seen in <FIG>. In some embodiments, the support frame <NUM> may be formed from a shape memory material or other material configured with a "trigger" (e.g., temperature, electrical current, etc.) such that the support frame <NUM> may remain in the delivery configuration until the support frame <NUM> is "activated", at which time the support frame <NUM> may shift to the expanded configuration. Other embodiments are also envisioned which may utilize mechanical expansion and/or a supporting expansion member to shift the occlusive medical device <NUM>, the expandable occlusive element <NUM>, and/or the support frame <NUM> from the delivery configuration to the expanded configuration.

In some embodiments, the expandable occlusive element <NUM> and/or the support frame <NUM> may include and/or comprise at least one strut, support, and/or member. In some embodiments, the expandable occlusive element <NUM> and/or the support frame <NUM> may include and/or comprise a plurality of struts, supports, and/or members interconnected, joined together, and/or integrally formed with each other. In at least some embodiments, the expandable occlusive element <NUM> and/or the support frame <NUM> may include a generally closed first end proximate the proximal tubular mounting portion <NUM> of the occlusive medical device <NUM> and a generally open second end opposite the generally closed first end, wherein the expandable occlusive element <NUM> and/or the support frame <NUM> expands radially outward from and opens away from the proximal tubular mounting portion <NUM> of the occlusive medical device <NUM>. In some embodiments, the expandable occlusive element <NUM> and/or the support frame <NUM> may include a generally closed first end proximate the proximal tubular mounting portion <NUM> of the occlusive medical device <NUM> and a generally closed second end opposite the generally closed first end, wherein a middle portion of the expandable occlusive element <NUM> and/or the support frame <NUM> expands radially outward from and/or between the generally closed first end and the generally closed second end. The expandable occlusive element <NUM> and/or the support frame <NUM> may have and/or define a longitudinal length along a longitudinal axis of the occlusive medical device <NUM>. Some suitable but non-limiting materials for the expandable occlusive element <NUM> and/or the support frame <NUM>, for example metallic materials, polymer materials, composite materials, etc., are described below.

As mentioned above, the occlusive membrane <NUM> may be fixedly attached to, encapsulate, and/or surround at least a portion of the support frame <NUM>. In some embodiments, the occlusive membrane <NUM> may be disposed on and/or attached to an inside surface of the expandable occlusive element <NUM> and/or the support frame <NUM>, an outside surface of the expandable occlusive element <NUM> and/or the support frame <NUM>, and/or may extend between individual struts, supports, and/or members of the expandable occlusive element <NUM> and/or the support frame <NUM>. In some embodiments, the occlusive membrane <NUM> may include a generally closed first end proximate the proximal tubular mounting portion <NUM> of the occlusive medical device <NUM> and a generally open second end opposite the generally closed first end. In some embodiments, the occlusive membrane <NUM> may include a generally closed first end proximate the proximal tubular mounting portion <NUM> of the occlusive medical device <NUM> and a generally closed second end opposite the generally closed first end. In some embodiments, the generally closed first end of the occlusive membrane <NUM> may be disposed at and/or may be fixedly attached to the proximal tubular mounting portion <NUM> of the occlusive medical device <NUM>. In some embodiments, the generally closed first end of the occlusive membrane <NUM> may be disposed distal of the proximal tubular mounting portion <NUM> of the occlusive medical device <NUM>. In some embodiments, the occlusive membrane <NUM> may extend along a portion of the longitudinal length of the expandable occlusive element <NUM> and/or the support frame <NUM>. For example, the second end of the occlusive membrane <NUM> may be disposed between the first end of the expandable occlusive element <NUM> and/or the support frame <NUM> and the second end of the expandable occlusive element <NUM> and/or the support frame <NUM>. In some embodiments, the second end of the occlusive membrane <NUM> may be substantially straight and/or arranged in a planar manner normal to the longitudinal axis of the occlusive medical device <NUM>. In some embodiments, the second end of the occlusive membrane <NUM> may be substantially scalloped and/or have a variable longitudinal length along and/or relative to the longitudinal axis of the occlusive medical device <NUM>. In some embodiments, the occlusive membrane <NUM> may extend along the entire longitudinal length of the expandable occlusive element <NUM> and/or the support frame <NUM>.

In some embodiments, the occlusive membrane <NUM> may be substantially nonporous and/or impermeable to fluid. For example, in some embodiments, blood or other fluid(s) may be unable to pass through the occlusive membrane <NUM>. As such, when the occlusive medical device <NUM> and/or the expandable occlusive element <NUM> is deployed within the vessel lumen (e.g., an artery, etc.) in the expanded configuration, the expandable occlusive element <NUM>, the support frame <NUM>, and/or the occlusive membrane <NUM> may extend across the vessel lumen and substantially and/or completely block and/or occlude fluid and/or blood flow through the vessel lumen. In some embodiments, the occlusive membrane <NUM> may include and/or be formed from a knitted, woven, and/or porous material having an impermeable coating and/or layer of material (e.g., polymeric material, etc.) formed thereon and/or thereover. In some embodiments, the occlusive membrane <NUM> may include and/or be formed from a knitted, woven, and/or porous material where blood quickly coagulates to form an impermeable barrier. Some suitable but non-limiting materials for the occlusive membrane <NUM>, for example metallic materials, polymer materials, composite materials, textile materials, etc., are described below.

<FIG> and <FIG> illustrate an example attachment mechanism of the occlusive medical device system. As mentioned above, the elongate shaft <NUM> may include a proximal end, a distal strain relief portion <NUM> opposite the proximal end, and a lumen <NUM> extending longitudinally through the elongate shaft <NUM>. The elongate shaft <NUM> may further comprise and/or include a plurality of retaining arms <NUM> extending distally from the distal strain relief portion <NUM>, the plurality of retaining arms <NUM> each having a distal end opposite the distal strain relief portion <NUM>. In some embodiments, the plurality of retaining arms <NUM> may be biased radially inward. In some embodiments, the plurality of retaining arms <NUM> may be self-biased radially inward. In some embodiments, the plurality of retaining arms <NUM> may be configured to deflect radially inward when unconstrained and/or when not biased radially outwardly by the release wire <NUM> as described herein. In some embodiments, the plurality of retaining arms <NUM> may comprise two retaining arms, three retaining arms, four retaining arms, or another suitable number of retaining arms.

In some embodiments, the plurality of retaining arms <NUM> may be arranged circumferentially about the longitudinal axis of the elongate shaft <NUM>. In some embodiments, a longitudinally-extending slot may extend between adjacent retaining arms <NUM>, thereby radially, angularly, and/or circumferentially spacing apart the adjacent retaining arms <NUM>. For example, centerlines (arranged generally parallel to the longitudinal axis of the elongate shaft <NUM>) of each of the plurality of retaining arms <NUM> may be arranged and/or spaced apart at equal and/or regular radial, angular, and/or circumferential intervals (e.g., <NUM> degrees apart, <NUM> degrees apart, etc.) about the longitudinal axis of the elongate shaft <NUM>. Alternatively, in some embodiments, centerlines (arranged generally parallel to the longitudinal axis of the elongate shaft <NUM>) of each of the plurality of retaining arms <NUM> may be arranged and/or spaced apart at unequal and/or irregular radial, angular, and/or circumferential intervals about the longitudinal axis of the elongate shaft <NUM>, with appropriate changes to the spacing (e.g., size of longitudinally-extending slot, etc.) of the plurality of retaining arms <NUM> to permit the desired inward deflection of the plurality of retaining arms <NUM>, as described herein. The plurality of retaining arms <NUM> may be formed and/or made by one or more of a variety of suitable means including, but not limited to, machining, cutting (e.g., laser, water jet, etc.), electro discharge machining, grinding, etc..

The elongate shaft <NUM> may include the release wire <NUM> slidably disposed within the lumen <NUM> of the elongate shaft <NUM> and axially translatable between the distal engagement position (e.g., <FIG> and <FIG>) and the proximal released position (e.g., <FIG>). As seen in the figures, the plurality of retaining arms <NUM> may extend into a lumen <NUM> extending longitudinally through the proximal tubular mounting portion <NUM>. The release wire <NUM> may be configured to engage the plurality of retaining arms <NUM> in the distal engagement position, thereby urging the plurality of retaining arms <NUM> radially outward into releasable engagement with the proximal tubular mounting portion <NUM> of the occlusive medical device <NUM> such that proximal axial translation of the elongate shaft <NUM> relative to the proximal tubular mounting portion <NUM> is prevented. When the release wire <NUM> is axially translated to and/or disposed in the proximal released position (e.g., <FIG>), the plurality of retaining arms <NUM> may deflect radially inward and disengage from the proximal tubular mounting portion <NUM> such that proximal axial translation of the elongate shaft <NUM> relative to the proximal tubular mounting portion <NUM> is permitted. In some embodiments, when the release wire <NUM> is axially translated to and/or disposed in the proximal released position (e.g., <FIG>), the plurality of retaining arms <NUM> may be biased and/or self-biased radially inward and disengage from the proximal tubular mounting portion <NUM> such that proximal axial translation of the elongate shaft <NUM> relative to the proximal tubular mounting portion <NUM> is permitted.

In at least some embodiments, each of the plurality of retaining arms <NUM> may include a protrusion <NUM> proximate the distal end thereof and extending radially outward from an outer surface and/or an outwardly-facing surface of the retaining arm <NUM>. In some embodiments, the protrusion <NUM> on each of the plurality of retaining arms <NUM> may be urged radially outward into releasable engagement with the proximal tubular mounting portion <NUM> of the occlusive medical device <NUM> when the release wire <NUM> is in the distal engagement position. The protrusion <NUM> of each of the plurality of retaining arms <NUM> may be formed on and/or added to its respective retaining arm using one or more suitable means including, but not limited to, adhesive, soldering, welding, grinding, electro discharge machining, etc..

In some embodiments, the proximal tubular mounting portion <NUM> may include a ridge <NUM> extending radially inward from an inwardly-facing surface of the proximal tubular mounting portion <NUM> proximate a proximal end of the lumen <NUM> and/or the proximal tubular mounting portion <NUM>. In some embodiments, the ridge <NUM> may be integrally formed with the proximal tubular mounting portion <NUM>, as seen in <FIG> for example. In some embodiments, the ridge <NUM> may be formed as a part of a tubular ring <NUM> fixedly attached to a proximal end of the proximal tubular mounting portion <NUM>, as seen in <FIG> for example. The tubular ring <NUM> may be fixedly attached to the proximal end of the proximal tubular mounting portion <NUM> using one or more suitable means, including but not limited to, welding, adhesives, mechanical fasteners, interference fit, etc. In some embodiments, the elongate shaft <NUM> and/or the plurality of retaining arms <NUM> may be axially slidable within the lumen <NUM> of the proximal tubular mounting portion <NUM>.

In some embodiments, the occlusive medical device <NUM> may include a radiopaque insert <NUM> disposed within a distal end of the lumen <NUM> extending longitudinally through the proximal tubular mounting portion <NUM>. In some embodiments, the radiopaque insert <NUM> may be fixedly and/or permanently secured within the distal end of the lumen <NUM> extending longitudinally through the proximal tubular mounting portion <NUM>. In some embodiments, the lumen <NUM> may not extend completely through the proximal tubular mounting portion <NUM>. For example, the distal end of the lumen <NUM> proximate the expandable occlusive element <NUM> and/or the support frame <NUM> may be closed.

As shown in <FIG>, advancing the elongate shaft <NUM> and the release wire <NUM> disposed in the distal engagement position distally and/or axially translating the elongate shaft <NUM> and the release wire <NUM> disposed in the distal engagement position distally within the lumen <NUM> extending through the proximal tubular mounting portion <NUM> urges the distal ends of each of the plurality of retaining arms <NUM> into contact with the radiopaque insert <NUM> and/or the closed distal end of the lumen <NUM> (where so configured). Further distal advancement and/or axial translation of the elongate shaft <NUM> relative to the delivery sheath <NUM> may advance and/or translate the occlusive medical device <NUM> distally relative to the delivery sheath <NUM>. In some embodiments, when the release wire <NUM> is disposed in the distal engagement position, withdrawing the elongate shaft <NUM> and the release wire <NUM> proximally urges the protrusion <NUM> of each of the plurality of retaining arms <NUM> into contact with a distal face of the ridge <NUM>, as shown in <FIG>. Withdrawing the release wire <NUM> axially within the elongate shaft <NUM> from the distal engagement position to the proximal released position permits the plurality of retaining arms <NUM> to deflect radially inward and disengage from the proximal tubular mounting portion <NUM>, as shown in <FIG>. In some embodiments, withdrawing the release wire <NUM> axially within the elongate shaft <NUM> from the distal engagement position to the proximal released position permits the plurality of retaining arms <NUM> to be biased and/or self-biased radially inward and thereby disengage from the proximal tubular mounting portion <NUM>, as shown in <FIG>. For example, when the retaining arms <NUM> are deflected and/or biased radially inward they have a diameter less than a proximal aperture <NUM>. As also seen in <FIG>, the ridge <NUM> defines the proximal aperture <NUM> having a diameter less than a diameter of the lumen <NUM> extending through the proximal tubular mounting portion <NUM>. The diameter of the proximal aperture <NUM> is also less than a maximum outer extent of the protrusions <NUM> of the plurality of retaining arms <NUM> when the release wire <NUM> is in the distal engagement position. When assembling the attachment mechanism, the plurality of retaining arms <NUM> are extended through the proximal aperture <NUM> into the lumen <NUM> of the proximal tubular mounting portion <NUM> prior to advancing the release wire <NUM> to the distal engagement position and into engagement with the plurality of retaining arms <NUM>.

Turning now to <FIG> and <FIG>, which illustrate configuration of the attachment mechanism, the distal strain relief portion <NUM> includes a plurality of micromachined or laser cuts extending at an angle relative to the longitudinal axis of the elongate shaft <NUM> from an outer surface of the elongate shaft <NUM> through to the lumen <NUM> extending through the elongate shaft <NUM>. As will be apparent to the skilled person, the distal strain relief portion <NUM> shown in <FIG> may also be used in conjunction with the attachment mechanism configurations of <FIG> and <FIG>. In some embodiments, the plurality of micromachined or laser cuts may be arranged at an oblique angle relative to the longitudinal axis of the elongate shaft <NUM>. In some embodiments, the plurality of micromachined or laser cuts may be arranged substantially perpendicular to the longitudinal axis of the elongate shaft <NUM>. The distal strain relief portion <NUM> having the plurality of micromachined or laser cuts may be included in any of the disclosed and/or alternative configurations of the elongate shaft <NUM> described herein. In some embodiments, other methods of forming the plurality of micromachined or laser cuts may be employed, including but not limited to, electro discharge machining (EDM), chemical reaction and/or dissolution, saw cutting, stamping, injection molding, etc..

Additionally, in some embodiments, the proximal tubular mounting portion <NUM> may lack the ridge <NUM> and may alternatively include a plurality of apertures <NUM> extending from an outer surface of the proximal tubular mounting portion <NUM> through to the lumen <NUM> extending through the proximal tubular mounting portion <NUM>, as seen in <FIG> for example. The plurality of apertures <NUM> may be configured to engage the plurality of retaining arms <NUM> when the release wire <NUM> is in the distal engagement position. In some embodiments, each of the protrusions <NUM> of the plurality of retaining arms <NUM> engages one of the plurality of apertures <NUM> of the proximal tubular mounting portion <NUM> when the release wire <NUM> is in the distal engagement position. When the release wire <NUM> is in the proximal released position, the plurality of retaining arms <NUM> may deflect radially inward and the protrusions <NUM> may disengage from the plurality of apertures <NUM> of the proximal tubular mounting portion <NUM>, as seen in <FIG>. In some embodiments, when the release wire <NUM> is in the proximal released position, the plurality of retaining arms <NUM> may be biased and/or self-biased radially inward and the protrusions <NUM> may thereby disengage from the plurality of apertures <NUM> of the proximal tubular mounting portion <NUM>. In the configuration illustrated in <FIG> and <FIG>, the protrusions <NUM> may be formed as rounded buttons or knobs extending radially outward from the outer surface of the plurality of retaining arms <NUM>. The plurality of apertures <NUM> may have a corresponding shape configured to complement and/or engage with the protrusions <NUM> of the plurality of retaining arms <NUM>.

In an alternative configuration illustrated in <FIG> and <FIG>, the protrusions <NUM> of the plurality of retaining arms <NUM> may be formed as rectilinear and/or elongated protuberances having a longitudinal dimension arranged generally parallel to the longitudinal axis of the elongate shaft <NUM>. Similar to the configuration of <FIG> and <FIG>, the proximal tubular mounting portion <NUM> may include a plurality of apertures <NUM> extending from an outer surface of the proximal tubular mounting portion <NUM> through to the lumen <NUM> extending through the proximal tubular mounting portion <NUM>, as seen in <FIG> for example. The plurality of apertures <NUM> may be configured to engage the plurality of retaining arms <NUM> when the release wire <NUM> is in the distal engagement position. In some embodiments, each of the protrusions <NUM> of the plurality of retaining arms <NUM> engages one of the plurality of apertures <NUM> of the proximal tubular mounting portion <NUM> when the release wire <NUM> is in the distal engagement position. When the release wire <NUM> is in the proximal released position, the plurality of retaining arms <NUM> may deflect radially inward and the protrusions <NUM> may disengage from the plurality of apertures <NUM> of the proximal tubular mounting portion <NUM>, as seen in <FIG>.

In another alternative configuration, the proximal tubular mounting portion <NUM> may include a plurality of protrusions <NUM> extending radially inward into the lumen <NUM> extending longitudinally through the proximal tubular mounting portion <NUM>, as seen in <FIG>. In some embodiments, the plurality of protrusions <NUM> may be formed as distinct, individual protrusions (e.g., balls, beads, rings, beaded rings, etc.) fixedly secured within openings extending through a side wall of the proximal tubular mounting portion <NUM>. In some embodiments, the plurality of protrusions <NUM> may be integrally formed with the proximal tubular mounting portion <NUM>. In the configuration shown in <FIG>, each of the plurality of retaining arms <NUM> of the elongate shaft <NUM> may include an aperture <NUM> (collectively, a plurality of apertures) configured to engage one of the plurality of protrusions <NUM> when the release wire is in the distal engagement position. Function and operation of the occlusive medical device system may be similar to that described above and/or herein. When the release wire <NUM> is in the proximal released position, the plurality of retaining arms <NUM> may deflect radially inward and the apertures and/or the plurality of apertures <NUM> may disengage from the plurality of protrusions <NUM> of the proximal tubular mounting portion <NUM>, as seen in <FIG>.

In another alternative configuration, the arrangement(s) described above may be inverted, wherein the features of the distal end of the elongate shaft <NUM> (e.g., the plurality of retaining arms <NUM>, the protrusion(s) <NUM>, etc.) may be disposed on and/or be formed with a proximal end of the occlusive medical device <NUM>, and the features of the proximal tubular mounting portion <NUM> (e.g., the lumen <NUM>, the ridge <NUM>, the tubular ring <NUM>, the proximal aperture <NUM>, the plurality of apertures <NUM>, etc.) may be disposed on and/or be formed with a distal end of the elongate shaft <NUM>. Other functionality may remain substantially the same as described above, with the plurality of retaining arms (now of the occlusive medical device) extending into the proximal tubular mounting portion (now of the elongate shaft), and the release wire <NUM> urging the plurality of retaining arms into releasable engagement with the proximal tubular mounting portion in the distal engagement position. Proximal translation of the release wire from the distal engagement position to the proximal release position may permit the plurality of retaining arms to disengage from the proximal tubular mounting portion and release the occlusive medical device from the elongate shaft.

In some embodiments, the occlusive medical device system may include a securement member <NUM> fixedly attached to and/or extending proximally from a proximal end of the elongate shaft <NUM>, and fixedly attached to a proximal end of the release wire <NUM>. The securement member <NUM> may include a proximal portion <NUM>, a distal portion <NUM>, and a wall <NUM> (as seen in <FIG> and <FIG>, for example) extending from a proximal end of the securement member <NUM> to a distal end of the securement member <NUM>. In at least some embodiments, the proximal portion <NUM> of the securement member <NUM> may be integrally formed with the distal portion <NUM> of the securement member <NUM> as a single unitary structure. Some suitable but non-limiting materials for the securement member <NUM>, for example metallic materials, polymer materials, composite materials, etc., are described below.

In some embodiments, the proximal portion <NUM> of the securement member <NUM> may be configured to disengage from the distal portion <NUM> of the securement member <NUM>. The proximal portion <NUM> of the securement member <NUM> may be fixedly attached to the proximal end of the release wire <NUM>. The distal portion <NUM> of the securement member <NUM> may be fixedly attached to the proximal end of the elongate shaft <NUM>. In at least some embodiments, an outer surface of the distal portion <NUM> of the securement member <NUM> may be fixedly attached to an inner surface of the elongate shaft <NUM> (e.g., a surface defining the lumen <NUM>). Alternatively, in some embodiments, an inner surface of the distal portion <NUM> of the securement member <NUM> may be fixedly attached to an outer surface of the elongate shaft <NUM>. In some embodiments, the proximal portion <NUM> of the securement member <NUM> may be releasably secured to and/or configured to disengage from the distal portion <NUM> of the securement member <NUM> at a joint <NUM>. In some embodiments, the joint <NUM> may be a perforation, a dissimilar polymer joint, a frangible link, or other releasable securement feature formed in the wall <NUM> of the securement member <NUM>.

In at least some embodiments, the securement member <NUM> may prevent axial translation of the release wire <NUM> relative to the elongate shaft <NUM> and/or the occlusive medical device <NUM> prior to disengagement of the proximal portion <NUM> of the securement member <NUM> from the distal portion <NUM> of the securement member <NUM>. Disengaging the proximal portion <NUM> of the securement member <NUM> from the distal portion <NUM> of the securement member <NUM> may permit the release wire <NUM> to axially translate relative to the distal portion <NUM> of the securement member <NUM> and/or the elongate shaft <NUM>. In other words, the wall <NUM> of the distal portion <NUM> of the securement member <NUM> may define a lumen, as seen in <FIG> and <FIG> for example, wherein the release wire <NUM> is slidably disposed within the lumen of the distal portion <NUM> of the securement member <NUM>. Upon disengagement of the proximal portion <NUM> of the securement member <NUM> from the distal portion <NUM> of the securement member <NUM>, as seen in <FIG>, axial translation of the proximal portion <NUM> relative to the distal portion <NUM> of the securement member <NUM> and/or the elongate shaft <NUM> may translate the release wire <NUM> relative to the elongate shaft <NUM> and/or the distal portion <NUM> of the securement member <NUM> to release the occlusive medical device <NUM> from the distal end of the elongate shaft <NUM>, as explained herein.

The release wire <NUM>, in the distal engagement position, urges the plurality of retaining arms <NUM> into releasable engagement with the proximal tubular mounting portion <NUM> of the occlusive medical device <NUM> when the proximal portion <NUM> of the securement member <NUM> is engaged with the distal portion <NUM> of the securement member <NUM>. For example, when the proximal portion <NUM> of the securement member <NUM> is disengaged and/or separated from the distal portion <NUM> of the securement member <NUM>, as seen in <FIG>, the release wire <NUM> is translated in a proximal direction relative to the elongate shaft <NUM> to the proximal released position, thereby permitting the plurality of retaining arms <NUM> to deflect radially inward and disengage from the proximal tubular mounting portion <NUM>, as described above. In some embodiments, the release wire <NUM> may be slidably disposed within the distal portion <NUM> of the securement member <NUM>, the elongate shaft <NUM>, the lumen <NUM>, the plurality of retaining arms <NUM>, and at least a portion of the proximal tubular mounting portion <NUM> and/or the lumen <NUM>.

In use, the elongate shaft <NUM> may have sufficient length to reach from the target site or area of interest to a position outside of the patient where the occlusive medical device system may be manipulated by an operator (e.g., clinician, physician, user, etc.). The operator of the occlusive medical device system may then place a first hand on the distal portion <NUM> of the securement member <NUM> and a second hand on the proximal portion <NUM> of the securement member <NUM>. The proximal portion <NUM> of the securement member <NUM> may be configured to disengage from the distal portion <NUM> of the securement member <NUM> at a location proximal of the delivery sheath <NUM>. In at least some embodiments, the proximal portion <NUM> of the securement member <NUM> may be disengaged from the distal portion <NUM> of the securement member <NUM> by bending, twisting, and/or pulling the proximal portion <NUM> of the securement member <NUM> relative to the distal portion <NUM> of the securement member <NUM>. In some embodiments, disengaging the proximal portion <NUM> of the securement member <NUM> from the distal portion <NUM> of the securement member <NUM> may include moving the proximal portion <NUM> of the securement member <NUM> relative to the distal portion <NUM> of the securement member <NUM> to separate the proximal portion <NUM> of the securement member <NUM> from the distal portion <NUM> of the securement member <NUM>. In some embodiments, disengaging the proximal portion <NUM> of the securement member <NUM> from the distal portion <NUM> of the securement member <NUM> may include using an external device (e.g., a torque device, an external handle, etc.) to move the proximal portion <NUM> of the securement member <NUM> relative to the distal portion <NUM> of the securement member <NUM>.

In some embodiments, the joint <NUM> may include a series of apertures (e.g., perforation) extending through the wall <NUM> of the securement member <NUM>. In some embodiments, the joint <NUM> may extend circumferentially about an entire circumference of the wall <NUM> of the securement member <NUM>. In some embodiments, the joint <NUM> may extend partially and/or intermittently about the entire circumference of the wall <NUM> of the securement member <NUM>. Additionally, while the joint <NUM> is illustrated in <FIG> and <FIG> as being generally oriented and/or positioned within a plane perpendicular to a longitudinal axis of the securement member <NUM>, other orientations and/or positioning may be used. For example, in some embodiments, the joint <NUM> may be oriented and/or positioned within or along a plane at an oblique angle to the longitudinal axis of the securement member <NUM>. Other, for example non-planar, configurations are also possible. The proximal portion <NUM> of the securement member <NUM> is disposed proximal of the joint <NUM> and the distal portion <NUM> of the securement member <NUM> is disposed distal of the joint <NUM>. As mentioned above, the proximal portion <NUM> of the securement member <NUM> may be releasably secured to and/or configured to disengage from the distal portion <NUM> of the securement member <NUM> at the joint <NUM> formed in the wall <NUM> of the securement member <NUM>.

The materials that can be used for the various components of the occlusive medical device system, the delivery sheath <NUM>, the elongate shaft <NUM>, the release wire <NUM>, the securement member <NUM>, the occlusive medical device <NUM>, the proximal tubular mounting portion <NUM>, the expandable occlusive element <NUM>, and/or the support frame <NUM>, the radiopaque insert <NUM>, etc. (and/or other systems or components disclosed herein) and the various elements thereof disclosed herein may include those commonly associated with medical devices. For simplicity purposes, the following discussion makes reference to the occlusive medical device system, the delivery sheath <NUM>, the elongate shaft <NUM>, the release wire <NUM>, the securement member <NUM>, the occlusive medical device <NUM>, the proximal tubular mounting portion <NUM>, the expandable occlusive element <NUM>, and/or the support frame <NUM>, the radiopaque insert <NUM>, etc. However, this is not intended to limit the devices and methods described herein, as the discussion may be applied to other elements, members, components, or devices disclosed herein, such as, but not limited to, the distal strain relief portion <NUM>, the plurality of retaining arms <NUM>, the protrusions <NUM>, the ridge <NUM>, the tubular ring <NUM>, etc. and/or elements or components thereof.

In some embodiments, the occlusive medical device system, the delivery sheath <NUM>, the elongate shaft <NUM>, the release wire <NUM>, the securement member <NUM>, the occlusive medical device <NUM>, the proximal tubular mounting portion <NUM>, the expandable occlusive element <NUM>, and/or the support frame <NUM>, the radiopaque insert <NUM>, etc., and/or components thereof may be made from a metal, metal alloy, polymer (some examples of which are disclosed below), a metal-polymer composite, ceramics, combinations thereof, and the like, or other suitable material. Some examples of suitable metals and metal alloys include stainless steel, such as 444V, <NUM>, and 314LV stainless steel; mild steel; nickel-titanium alloy such as linear-elastic and/or super-elastic nitinol; other nickel alloys such as nickel-chromium-molybdenum alloys (e.g., UNS: N06625 such as INCONEL® <NUM>, UNS: N06022 such as HASTELLOY® C-<NUM>®, UNS: N10276 such as HASTELLOY® C276®, other HASTELLOY® alloys, and the like), nickel-copper alloys (e.g., UNS: N04400 such as MONEL® <NUM>, NICKELVAC® <NUM>, NICORROS® <NUM>, and the like), nickel-cobalt-chromium-molybdenum alloys (e.g., UNS: R44035 such as MP35-N® and the like), nickel-molybdenum alloys (e.g., UNS: N10665 such as HASTELLOY® ALLOY B2®), other nickel-chromium alloys, other nickel-molybdenum alloys, other nickel-cobalt alloys, other nickel-iron alloys, other nickel-copper alloys, other nickel-tungsten or tungsten alloys, and the like; cobalt-chromium alloys; cobalt-chromium-molybdenum alloys (e.g., UNS: R44003 such as ELGILOY®, PHYNOX®, and the like); platinum enriched stainless steel; titanium; platinum; palladium; gold; combinations thereof; and the like; or any other suitable material.

In at least some embodiments, portions or all of the occlusive medical device system, the delivery sheath <NUM>, the elongate shaft <NUM>, the release wire <NUM>, the securement member <NUM>, the occlusive medical device <NUM>, the proximal tubular mounting portion <NUM>, the expandable occlusive element <NUM>, and/or the support frame <NUM>, the radiopaque insert <NUM>, etc., and/or components thereof, may also be doped with, made of, or otherwise include a radiopaque material. Radiopaque materials are understood to be materials capable of producing a relatively bright image on a fluoroscopy screen or another imaging technique during a medical procedure. This relatively bright image aids a user in determining the location of the occlusive medical device system, the delivery sheath <NUM>, the elongate shaft <NUM>, the release wire <NUM>, the securement member <NUM>, the occlusive medical device <NUM>, the proximal tubular mounting portion <NUM>, the expandable occlusive element <NUM>, and/or the support frame <NUM>, the radiopaque insert <NUM>, etc. Some examples of radiopaque materials can include, but are not limited to, gold, platinum, palladium, tantalum, tungsten alloy, polymer material loaded with a radiopaque filler, and the like. Additionally, other radiopaque marker bands and/or coils may also be incorporated into the design of the occlusive medical device system, the delivery sheath <NUM>, the elongate shaft <NUM>, the release wire <NUM>, the securement member <NUM>, the occlusive medical device <NUM>, the proximal tubular mounting portion <NUM>, the expandable occlusive element <NUM>, and/or the support frame <NUM>, the radiopaque insert <NUM>, etc. to achieve the same result.

In some embodiments, a degree of Magnetic Resonance Imaging (MRI) compatibility is imparted into the occlusive medical device system, the delivery sheath <NUM>, the elongate shaft <NUM>, the release wire <NUM>, the securement member <NUM>, the occlusive medical device <NUM>, the proximal tubular mounting portion <NUM>, the expandable occlusive element <NUM>, and/or the support frame <NUM>, the radiopaque insert <NUM>, etc. For example, the occlusive medical device system, the delivery sheath <NUM>, the elongate shaft <NUM>, the release wire <NUM>, the securement member <NUM>, the occlusive medical device <NUM>, the proximal tubular mounting portion <NUM>, the expandable occlusive element <NUM>, and/or the support frame <NUM>, the radiopaque insert <NUM>, etc., and/or components or portions thereof, may be made of a material that does not substantially distort the image and create substantial artifacts (e.g., gaps in the image). Certain ferromagnetic materials, for example, may not be suitable because they may create artifacts in an MRI image. The occlusive medical device system, the delivery sheath <NUM>, the elongate shaft <NUM>, the release wire <NUM>, the securement member <NUM>, the occlusive medical device <NUM>, the proximal tubular mounting portion <NUM>, the expandable occlusive element <NUM>, and/or the support frame <NUM>, the radiopaque insert <NUM>, etc., or portions thereof, may also be made from a material that the MRI machine can image. Some materials that exhibit these characteristics include, for example, tungsten, cobalt-chromium-molybdenum alloys (e.g., UNS: R44003 such as ELGILOY®, PHYNOX®, and the like), nickel-cobalt-chromium-molybdenum alloys (e.g., UNS: R44035 such as MP35-N® and the like), nitinol, and the like, and others.

In some embodiments, the occlusive medical device system, the delivery sheath <NUM>, the elongate shaft <NUM>, the release wire <NUM>, the securement member <NUM>, the occlusive medical device <NUM>, the proximal tubular mounting portion <NUM>, the expandable occlusive element <NUM>, and/or the support frame <NUM>, the radiopaque insert <NUM>, etc., and/or portions thereof, may be made from or include a polymer or other suitable material. Some examples of suitable polymers may include polytetrafluoroethylene (PTFE), ethylene tetrafluoroethylene (ETFE), fluorinated ethylene propylene (FEP), polyoxymethylene (POM, for example, DELRIN® available from DuPont), polyether block ester, polyurethane (for example, Polyurethane 85A), polypropylene (PP), polyvinylchloride (PVC), polyether-ester (for example, ARNITEL® available from DSM Engineering Plastics), ether or ester based copolymers (for example, butylene/poly(alkylene ether) phthalate and/or other polyester elastomers such as HYTREL® available from DuPont), polyamide (for example, DURETHAN® available from Bayer or CRISTAMID® available from Elf Atochem), elastomeric polyamides, block polyamide/ethers, polyether block amide (PEBA, for example available under the trade name PEBAX®), ethylene vinyl acetate copolymers (EVA), silicones, polyethylene (PE), Marlex high-density polyethylene, Marlex low-density polyethylene, linear low density polyethylene (for example REXELL®), polyester, polybutylene terephthalate (PBT), polyethylene terephthalate (PET), polytrimethylene terephthalate, polyethylene naphthalate (PEN), polyetheretherketone (PEEK), polyimide (PI), polyetherimide (PEI), polyphenylene sulfide (PPS), polyphenylene oxide (PPO), poly paraphenylene terephthalamide (for example, KEVLAR®), polysulfone, nylon, nylon-<NUM> (such as GRILAMID® available from EMS American Grilon), perfluoro(propyl vinyl ether) (PFA), ethylene vinyl alcohol, polyolefin, polystyrene, epoxy, polyvinylidene chloride (PVdC), poly(styrene-b-isobutylene-b-styrene) (for example, SIBS and/or SIBS 50A), polycarbonates, ionomers, polyurethane silicone copolymers (for example, ElastEon® from Aortech Biomaterials or ChronoSil® from AdvanSource Biomaterials), biocompatible polymers, other suitable materials, or mixtures, combinations, copolymers thereof, polymer/metal composites, and the like. In some embodiments, the sheath can be blended with a liquid crystal polymer (LCP). For example, the mixture can contain up to about <NUM> percent LCP.

In some embodiments, the occlusive medical device system, the delivery sheath <NUM>, the elongate shaft <NUM>, the release wire <NUM>, the securement member <NUM>, the occlusive medical device <NUM>, the proximal tubular mounting portion <NUM>, the expandable occlusive element <NUM>, and/or the support frame <NUM>, the occlusive membrane <NUM>, the radiopaque insert <NUM>, etc. may include and/or be formed from a textile material. Some examples of suitable textile materials may include synthetic yams that may be flat, shaped, twisted, textured, pre-shrunk or un-shrunk. Synthetic biocompatible yams suitable for use in the present invention include, but are not limited to, polyesters, including polyethylene terephthalate (PET) polyesters, polypropylenes, polyethylenes, polyurethanes, polyolefins, polyvinyls, polymethylacetates, polyamides, naphthalene dicarboxylene derivatives, natural silk, and polytetrafluoroethylenes. Moreover, at least one of the synthetic yarns may be a metallic yarn or a glass or ceramic yarn or fiber. Useful metallic yarns include those yams made from or containing stainless steel, platinum, gold, titanium, tantalum or a Ni-Co-Cr-based alloy. The yarns may further include carbon, glass or ceramic fibers. Desirably, the yarns are made from thermoplastic materials including, but not limited to, polyesters, polypropylenes, polyethylenes, polyurethanes, polynaphthalenes, polytetrafluoroethylenes, and the like. The yams may be of the multifilament, monofilament, or spun-types. The type and denier of the yarn chosen may be selected in a manner which forms a biocompatible and implantable prosthesis and, more particularly, a vascular structure having desirable properties.

Claim 1:
An occlusive medical device system, comprising:
an elongate shaft (<NUM>) having a proximal end, a distal strain relief portion (<NUM>), and a lumen (<NUM>) extending longitudinally through the elongate shaft (<NUM>), the elongate shaft further comprising a plurality of retaining arms (<NUM>) extending distally from the distal strain relief portion (<NUM>), the plurality of retaining arms (<NUM>) each having a distal end;
an occlusive medical device (<NUM>) configured to occlude fluid flow through a vessel lumen, the occlusive medical device including a proximal mounting portion (<NUM>) fixed to an expandable occlusive element (<NUM>); and
a release wire (<NUM>) disposed within the lumen of the elongate shaft (<NUM>) and axially translatable between a distal engagement position and a proximal released position;
wherein the plurality of retaining arms (<NUM>) extend into the proximal mounting portion (<NUM>);
wherein the release wire (<NUM>) is configured to engage the plurality of retaining arms (<NUM>) in the distal engagement position, thereby urging the plurality of retaining arms (<NUM>) radially outward into releasable engagement with the proximal mounting portion (<NUM>) of the occlusive medical device (<NUM>);
wherein when the release wire (<NUM>) is in the proximal released position, the plurality of retaining arms (<NUM>) is deflectable radially inward to disengage from the proximal mounting portion (<NUM>),
wherein the distal strain relief portion (<NUM>) includes a plurality of micromachined or laser cuts extending at an angle to a longitudinal axis of the elongate shaft (<NUM>) from an outer surface of the elongate shaft through to the lumen (<NUM>) extending through the elongate shaft (<NUM>).