Patent Description:
The present disclosure relates to apparatuses and systems that include constructing coverings used in delivery of implantable medical devices. More specifically, the present disclosure relates to apparatuses and systems that include constructing coverings for constraining an expandable device during device delivery.

Stents and stent-grafts may be utilized to radially support a variety of tubular passages in the body, including arteries, veins, airways, gastrointestinal tracts, and biliary tracts. The preferred method of placing these devices has been to use specialized delivery systems to precisely place and deploy a device at the site to be treated. These delivery systems allow the practitioner to minimize the trauma and technical difficulties associated with device placements. Attributes of delivery systems include: low profile; ability to pass through introducer sheaths; ability to negotiate tortuous vasculature, smoothly and atraumatically; protection of constrained devices; and ability to accurately position and deploy the device.

Stents or stent-grafts may be deployed and plastically deformed by using an inflatable balloon (e.g., balloon expandable stents) or to self-expand and elastically recover (e.g., self expandable devices) from a collapsed or constrained delivery diameter to an expanded and deployed diameter. Some stents are designed to elastically recover by being manufactured at their functional diameter out of a material that has elastic recovery properties, and then radially compressed to be mounted on a delivery catheter.

These stent and stent-graft devices may be held, compressed, or constrained in the delivery configuration prior to and during delivery to a target location. <CIT> is directed to a stent delivery system that includes a self-expanding stent with a longitudinal length and a plurality of individual suture loops spaced along the longitudinal length of the stent, wherein the stent is compressed by the plurality of individual suture loops. The stent delivery system also includes a longitudinal pull member that secures the plurality of individual suture loops about the stent, wherein the plurality of individual suture loops are configured to separate from about the stent when the longitudinal pull wire is removed. <CIT> is directed to a stent graft with an opening and a method for binding the stent graft. The stent graft includes multiple annular wave-shaped stent sections and a tectorial membrane pipe seamed with these stent sections. The tectorial membrane pipe (<NUM>) has at least one opening. There is an opening fixing wire seamed with the opening for supporting the opening. <CIT> is directed to a system-for repairing an anatomic duct, the system comprising an implant having a tubular body adapted to be radially expanded, once the implant is arranged in the duct and also a device for installing the implant in said duct. The device comprises a tie for maintaining the body in a restricted configuration, for the implantation thereof in the duct, and means for releasing the tie in order to allow the implant to radially expand. <CIT> is directed to a system for deploying a stent-graft within a body vessel. The system includes an expandable stent-graft having expandable stent rings attached thereto and a cannula extending through the stent-graft. The system includes a plurality of diameter reducing connectors extending around the circumference of the graft for reducing the diameter of the graft. The system further includes a plurality of trigger wires extending longitudinally along the perimeter of the graft. The trigger wires extend through the diameter reducing connectors to constrain the connectors for reducing the diameter of the stent-graft. The trigger wires are also releasably attached to the apices of a bare stent portion extending from the proximal end of the graft body. The trigger wires can be sequentially retracted to release the bare stent and the diameter reducing connectors to expand the stent-graft radially into engagement with the wall of the body vessel. <CIT> is directed to a temporary diameter reduction constraint arrangement for a stent graft. The arrangement comprises: primary and secondary release wires extending along the graft; a plurality of loops of thread, each loop engaged with either the primary or secondary wire and engaged around a portion of the graft circumferentially spaced away from its release wire, and drawn tight to reduce the diameter of the graft; an end constraint arrangement comprising four of the plurality of loops of thread arranged into a first and second pairs engaged with respective primary and secondary wires; and an intermediate constraint arrangement comprising a fifth and sixth of the plurality of loops of thread arranged into a third pair, the third pair engaged with the primary release wire, the primary release wire deviating towards the secondary release wire so as to locate the intermediate constraint arrangement substantially in-line with the end constraint arrangement. <CIT> is directed to a method of easily holding a stent in a reduced diameter state with a simple structure without requiring an outside sheath or a special device, and of easily and reliably controlling the expanded state of the stent. ;The device comprises a first loop-shaped part for inserting the stent in a reduced diameter state and a loop-shaped part for inserting a shaft are formed into a knot to be loosened by drawing in a wire. The stent in the reduced diameter state is inserted into the first loop-shaped part of the wire, and the shaft is inserted into the second loop-shaped part. Then, a second loop part for inserting the narrowed stent is formed as a knot to be loosened by drawing in the wire, and the stent in the reduced diameter state is inserted into the first loop-shape part of the wire, then the shaft is inserted into the second loop-shaped part. The above procedure is repeated a plurality of times from the distal end or near the distal end to the base end or near the base end on the opposite side.

Disclosed herein is a delivery system including an implantable medical device; a constraining mechanism including interlocking loops configured to releasably constrain the implantable medical device in a delivery configuration, and a lock line arranged through a portion of the interlocking loops and configured to be withdrawn to enable release of the constraining mechanism. The lock line comprises an adhesive on an exterior surface of the lock line to increase friction between the interlocking loops. In the delivery system, each loop of the interlocking loops includes at least two strands forming the loop, and wherein one strand of the loop overlaps with a strand of an adjacent loop to form an interlocking loop. The lock line is arranged in at least one of the knot rows to prevent the knot row from unraveling.

The interlocking loops may include at least two strands arranged in a warp knit having multiple knot rows spaced around a circumference of the implantable medical device.

The lock line may be arranged through one row of the interlocking loops.

The lock line may be arranged through both rows of the loops.

When one of the knot rows of the delivery system is disrupted, the constraining mechanism may unravel and may be remotely removable when a force is applied to a deployment line.

The linchpin may be removable to allow a user to selectively unravel the at least one knot row.

The lock line may be configured to resist deployment when a ratio of a deployed diameter of the device to a delivery diameter of the device is less than <NUM>.

The lock line may be arranged through each of the knot rows to allow for controlled release of each of the knot rows.

The lock line may be a first lock line, and wherein the system may further comprise a second lock line arranged through another portion of interlocking loops.

The second lock line may be spaced a distance from the first lock line around the circumference of the constraining mechanism.

The first lock line may be configured to release a first portion of the interlocking loops and the second lock line is configured to release a second portion of the interlocking loops.

Also disclosed but not claimed herein is a delivery system including an implantable medical device; a constraining mechanism configured to constrain the implantable medical device to a delivery configuration, and a lock line configured to increase friction between interlocking loops of at least one knot row to maintain the constraining mechanism in the delivery configuration.

The lock line may be removed from the delivery system by applying a force to the lock line, and wherein removal of the lock line releases the constraining mechanism.

Removal of the lock line may release each loop of the interlocking loops sequentially.

Applying the force to the lock line may decrease friction between the interlocking strands of the knot row to sequentially unravel the knot row.

As the terms are used herein with respect to ranges of measurements "about" and "approximately" may be used, interchangeably, to refer to a measurement that includes the stated measurement and that also includes any measurements that are reasonably close to the stated measurement, but that may differ by a reasonably small amount such as will be understood, and readily ascertained, by individuals having ordinary skill in the relevant arts to be attributable to measurement error, differences in measurement and/or manufacturing equipment calibration, human error in reading and/or setting measurements, adjustments made to optimize performance and/or structural parameters in view of differences in measurements associated with other components, particular implementation scenarios, imprecise adjustment and/or manipulation of objects by a person or machine, and/or the like.

While multiple examples are disclosed, still other embodiments will become apparent to those skilled in the art from the following detailed description, which shows and describes illustrative examples, as long as they are covered by the appended claims. Accordingly, the drawings and detailed description are to be regarded as illustrative in nature rather than restrictive in nature.

Persons skilled in the art will readily appreciate that various aspects of the present disclosure can be realized by any number of apparatus configured to perform the intended functions. It should also be noted that the accompanying drawing figures referred to herein are not necessarily drawn to scale, but may be exaggerated to illustrate various aspects of the present disclosure, and in that regard, the drawing figures should not be construed as limiting.

Various aspects of the present disclosure are directed toward apparatuses, systems, and methods that include forming or manufacturing a constraining mechanism. The constraining mechanisms are configured to hold, compress, or constrain an implantable medical device (e.g., a stent, stent-graft, balloon, or other expandable medical device) in a delivery configuration prior to and during delivery to a target location. In certain instances, the constraining mechanism includes one or more fibers.

<FIG> is a top plan view of a delivery system <NUM> including a catheter <NUM> with a removable constraint <NUM>, according to some embodiments. As shown in <FIG>, the removable constraint <NUM> is configured to constrain an implantable medical device <NUM> to a delivery configuration. The removable constraint102 may include one or more fibers <NUM> arranged about the device <NUM> to maintain the removable constraint <NUM> in a constrained configuration.

The removable constraint <NUM> is arranged along a length of the device <NUM>. The removable constraint <NUM> is also circumferentially arranged about the device <NUM> and may substantially cover the device <NUM> for delivery. The one or more fibers <NUM> may be arranged within a lumen (not shown) of the catheter <NUM> and extend toward a proximal end of the catheter <NUM> that is arranged external to a patient during delivery of the device <NUM>. The one or more fibers <NUM> include a proximal end <NUM> that a user may apply tension to in order to release the removable constraint <NUM> and deploy the device <NUM>.

In certain instances, the one or more fibers <NUM> release similar to a rip cord such that interlocking portions (e.g., overlapping fibers or knots) sequentially release along the length of the device <NUM>. As is explained in greater detail below, the removable constraint <NUM> is formed by interlocking together the one or more fibers <NUM> directly on the device <NUM>. The device <NUM> may be a stent, stent-graft, a balloon, or a similar device.

<FIG> is a side view of the device <NUM> including the constraining mechanism <NUM>, in accordance with an embodiment. As shown, the device <NUM> includes a delivery diameter D1 and a deployed diameter D2 (not shown) that is larger than the delivery diameter D1. The removable constraint <NUM> is attached to the device <NUM> at its delivery diameter D1. As shown, the constraining mechanism <NUM> includes at least two interlocking strands in the form of a warp knit. For example, the constraining mechanism <NUM> includes a first interlocking strand <NUM> and a second interlocking strand <NUM>. The constraining mechanism <NUM> includes a lock line <NUM> configured to release the constraining mechanism <NUM> and release the device <NUM> from the delivery diameter D1 to the deployed diameter D2 in response to a force applied to the lock line <NUM>. In other terms, when the lock line <NUM> is removed from the constraining mechanism <NUM>, the constraining mechanism <NUM> is released and decreases friction between the interlocking loops to sequentially unravel the at least one knot row.

The device <NUM> may have a desired deployed diameter D2 from about <NUM>-<NUM>, or <NUM>-<NUM>, or <NUM>-<NUM>, for example, and a delivery diameter D1 that is less than the deployed diameter D2. For example, in some instances, a ratio of the delivery diameter D1 of the device <NUM> to the deployed diameter D2 (not shown) of the device <NUM> is less than about <NUM>, less than about <NUM>, less than about <NUM>, less than about <NUM>, or less than about <NUM>. For reference, the term "diameter" is not meant to require a circular cross-section, and is instead to be understood broadly to reference a maximum transverse cross-sectional dimension of a device <NUM>.

<FIG> is a schematic view of interlocking strands of the constraining mechanism <NUM>, in accordance with an embodiment. The interlocking strands (e.g., the first and second interlocking strands <NUM>, <NUM> as shown) are interwoven with one another to form at least one knot <NUM>. As shown, the knot <NUM> is formed of interlocking loops formed from the first and second interlocking strands <NUM>, <NUM>. For example, the first interlocking loop <NUM> is formed by the first interlocking strand <NUM> and is interwoven with the second interlocking loop <NUM> formed by the second interlocking strand <NUM>. This interlocking, looped configuration may be repeated to extend the longitudinal length of the device <NUM> (as shown in <FIG>, <FIG>, and <FIG>) to form a knot row <NUM>.

The lock line <NUM> is arranged through the knot row <NUM> of the constraining mechanism <NUM>. The lock line <NUM>, in connection with the interlocking strands <NUM>, <NUM>, is configured to lessen ramping (or deployment angle) of the device <NUM> prior to being released. For example, the lock line <NUM> may be configured to lessen ramping of the device <NUM> prior to the knots <NUM> being released in sequence. The device <NUM> begins to expand to a larger diameter after release of the constraining mechanism <NUM>.

As discussed in further detail below, the lock line <NUM> lessens ramping of the device <NUM> (which may lead to uncontrolled or undesired deployment) by maintaining a location of each of the knots <NUM>, relative to the device <NUM>, as the knots <NUM> are released in sequence. The lock line <NUM>, in this manner, lessens undesired or pre-deployment of the device. In some instances, the lock line <NUM> can be a fiber, wire, rod, or other similar device that is capable of extending along the knot row <NUM>.

As force is applied to the lock line <NUM> and the lock line <NUM> is removed from the constraining mechanism <NUM>, each of the knots <NUM> may be released in sequence. The knots <NUM> may be released as the lock line <NUM> is withdrawn or the knots <NUM> may be released by applying tension to a deployment line <NUM>, which is an end of one or both of the interlocking strands <NUM>, <NUM>. Removal of the lock line <NUM> decreases friction between the interlocking strands of the constraining mechanism <NUM> to sequentially unravel the knot row <NUM>. Thus, when force is applied to the lock line <NUM>, the constraining mechanism <NUM> is remotely removable by a user.

In some instances, the lock line <NUM> is arranged through one of the interlocking loops (e.g., either the first or second interlocking loop <NUM>, <NUM>), as shown in <FIG>. In other instances, the lock line <NUM> can be arranged through both of the interlocking loops, as shown in <FIG>. The lock line <NUM> is incorporated into at least one of the knots <NUM> to prevent the knot <NUM> from unraveling. Examples of suitable lock lines <NUM> can include linchpins, wires, metallic lines, fibers, and various adhesives. In certain instances, the lock line <NUM> is removable to allow a user to selectively unravel the respective knot <NUM>. In some instances, the lock line <NUM> may be incorporated into each of the knots <NUM> for controlled release of all knots <NUM> of a respective knot row <NUM> (<FIG>).

<FIG> is a schematic view of interlocking strands of the constraining mechanism <NUM> having multiple lock lines <NUM>, in accordance with an embodiment. As shown, the knot row <NUM> can include more than one lock line <NUM>. For example, the knot row <NUM> may include a first lock line 124a arranged through a first portion of the interlocking loops and a second lock line 124b arranged through a second portion of the interlocking loops. In certain instances, the first lock line 124a and the second lock line 124b longitudinally overlap. The first lock line 124a and the second lock line 124b may originate from a user end of the delivery system <NUM> that uses the constraining mechanism <NUM>. In other instances, one of the first lock line 124a and the second lock line 124b may be coupled to or bifurcate from the other of the first lock line 124a and the second lock line 124b. The first lock line 124a may configured to release the first portion of the interlocking loops while the second lock line 124b is configured to release the second portion of interlocking loops. In some instances, the constraining mechanism <NUM> may include more than one knot row <NUM>.

The knots <NUM> may be released as the lock lines 124a, 124b are withdrawn or the knots <NUM> may be released by applying tension to a deployment line <NUM>, which is an end of one or both of the interlocking strands <NUM>, <NUM>. Removal of the lock lines 124a, 124b decreases friction between the interlocking strands of the constraining mechanism <NUM> to sequentially unravel the knot row <NUM>. Thus, when force is applied to the lock line <NUM>, the constraining mechanism <NUM> is remotely removable by a user.

<FIG> is an end view of the device <NUM> including the constraining mechanism <NUM>, according to an embodiment. As shown, the constraining mechanism <NUM> includes two knot rows. For example, the constraining mechanism <NUM> includes a first knot row 122a and a second knot row 122b spaced a distance from the first knot row 122a about the circumference of the constraining mechanism <NUM>. In some instances, each of the knot row 122a, 122b includes a lock line <NUM> (e.g., a first lock line 124a and a second lock line 124b). For example, the first knot row 122a can include the first lock line 124a and the second knot row 122b can include the second lock line 124b.

<FIG> are end views of the device <NUM> including the constraining mechanism <NUM>, according to an embodiment. As shown, the constraining mechanism <NUM> can include more than two knot rows <NUM>. For example, the constraining mechanism <NUM> can include four, six, or more knot rows <NUM> spaced about the circumference of the constraining mechanism <NUM> as desired. The loops in the knot rows <NUM> may be of different diameters in certain instances.

<FIG> are images of a delivery system in a delivery configuration and a semi-deployed configuration, respectively, in accordance with an embodiment. As shown in <FIG>, the removable constraint <NUM> is attached to the device <NUM> at its delivery diameter D1. During deployment, a force is applied to the lock line <NUM> to release the removable constraint <NUM> by unraveling the knot row <NUM>, as shown in <FIG>. In certain instances, the knot row <NUM> may sequentially release, after the lock line <NUM> is removed, by applying a force to the deployment line <NUM>. The device <NUM> is released to the deployed diameter D2 as the removable constraint <NUM> is released.

The lock line <NUM> can lessen ramping of the device <NUM> prior to being released. For example, the lock line <NUM> may lessen ramping of the device <NUM> prior to the knots of the knot row <NUM> being released in sequence. The device <NUM> begins to expand to a larger diameter after release of the constraining mechanism <NUM>. The device <NUM> may be have an angle A between the portions held by the constraining mechanism <NUM> and portions that have been expanded or are beginning to expand. Due to the angle A and the device <NUM> expending a force to deploy to the deployed diameter D2, prior devices may shift due to ramping of the device <NUM>. The lock line <NUM>, however, resists spontaneous deployment that can be magnified by ramping of the device <NUM> with or without application of a radial force by the compressed stent.

Claim 1:
A delivery system (<NUM>) comprising:
an implantable medical device (<NUM>);
a constraining mechanism (<NUM>) including interlocking loops configured to releasably constrain the implantable medical device (<NUM>) in a delivery configuration, and
a lock line (<NUM>) arranged through a portion of the interlocking loops and configured to be withdrawn to enable release of the constraining mechanism (<NUM>), wherein the lock line (<NUM>) comprises an adhesive on an exterior surface of the lock line (<NUM>) to increase friction between the interlocking loops;
wherein each loop of the interlocking loops includes at least two strands (<NUM>, <NUM>) forming the loop;
wherein one strand (<NUM>) of the loop overlaps with a strand (<NUM>) of an adjacent loop to form an interlocking loop (<NUM>, <NUM>), and
wherein the lock line (<NUM>) is arranged in at least a knot row (<NUM>) to prevent the knot row (<NUM>) from unraveling.