Systems and methods for sheathing an implantable device

Systems and methods are disclosed for delivering a stent to a lumen internal to a body of a patient and for sheathing a stent just prior to an insertion procedure. One embodiment comprises a delivery device having a partially sheathed configuration, a fully sheathed delivery configuration, and a deployed configuration. A panchor (combination pusher and anchor) is configured to engage and limit proximal and distal movement of the implantable device. An outer sheath surrounds a distal portion of an inner member and retains the implantable device near the distal end. The outer sheath is slidably moveable relative to the inner member to deploy the implantable device. Proximal movement of a trigger results in movement of the outer sheath to deploy the implantable device. A sheathing mechanism is configured to crimp and fully sheathe the implantable device prior to a deployment procedure.

TECHNICAL FIELD

The present disclosure is directed to systems and methods for delivering a stent to a lumen internal to a body of a patient, and more particularly to systems and methods for sheathing a stent just prior to an insertion procedure.

DETAILED DESCRIPTION

The present disclosure relates to systems and methods for deploying a crimpable implantable device within a body of a patient. For example, the disclosed systems and methods may provide for deploying a valved stent within a lumen of a body of a patient. The disclosed embodiments may allow the implantable device to be stored and/or transported in partially sheathed (and also partially deployed) storage configuration, such that a portion of the implantable device is crimped and/or sheathed within a stent delivery device. A portion of the implantable device may also remain unsheathed and in an expanded (or uncrimped) state. In the case of a valved stent, the portion of the valved stent that includes the valve can remain unsheathed in an expanded state to prevent the valve from enduring prolonged periods of compression and deformation (e.g., during storage and/or transport) that can result in deformation of the valve.

The disclosed embodiments may further allow a practitioner to fully crimp and/or fully sheathe the implantable device and transition the delivery device into a delivery configuration just prior to delivery of the implantable device to a desired location within a target lumen. The disclosed embodiments may further allow deployment of the implantable device to an expanded fully deployed state.

Implantable medical devices are valuable tools of modern medicine. In general, an implantable device is a device or structure configured to be inserted or embedded into a patient for a variety of functions. Implantable devices include stents, filters, markers, drug delivery devices, valves, and monitors.

Stents are implantable devices that are inserted into body lumina, such as vessels or passages, to keep the lumen open and prevent closure due to a stricture, external compression, or internal obstruction. Stents are commonly used to keep blood vessels open in the coronary arteries, and they are frequently inserted into the ureters to maintain drainage from the kidneys, the bile duct for pancreatic cancer or cholangiocarcinoma, or the esophagus or airways for strictures or cancer.

In order to serve a desired function, an implantable device should be delivered precisely and oriented correctly. Improper installation can lead to several adverse complications, including tissue luminal inflammation and tissue granulation. In order to facilitate the delivery of implantable devices, delivery devices, such as endoscopes and catheters, have been utilized to deploy implantable devices more precisely.

Delivery devices vary in shape and structure. However, in general, a delivery device may include a handle and one or more movable tubular members extending from the handle. The delivery device may further include a deployment mechanism for moving or operating the tubular members between positions. The one or more moveable tubular members typically include an inner tubular member disposed within an outer tubular member or sheath. The outer tubular member is typically shorter than the inner tubular member and movable relative to the inner tubular member. A distal region of the outer tubular member generally surrounds the implantable device. In the case of a stent, the outer tubular member may maintain the stent sheathed in a crimped state in the sheathed delivery configuration, while a distal region of the inner tubular member is surrounded by the stent. Once the sheathed stent is properly positioned at a target deployment site, the outer tubular member may be retracted to deploy the stent and allow the stent to radially expand.

Many presently available delivery devices require an implantable device to be fully crimped and/or sheathed by special equipment prior to storage and/or transport and prior to deployment for use, for example in treating a lumen of a body of a patient. As used herein, the terms “crimp” and “crimping” refer to compressing or drawing a crimpable implantable device inward, radial toward a longitudinal axis of the implantable device, to bring the implantable device to approximately an original or initial size. Crimping may occur independent from and with limited compression or expansion longitudinally along a longitudinal axis of the implantable device. In other words, crimping may involve limited or no change in a longitudinal dimension of the implantable device.

Some implantable devices are designed to be sheathed (or re-sheathed) for removal from the body, yet such implantable devices may be configured such that they cannot be subsequently deployed for use without properly being crimped before being sheathed. A stent that is re-sheathed may not necessarily be crimped or otherwise returned to a crimped state. The re-sheathing process may damage, deform, or otherwise alter the structural integrity or other characteristic of the implantable device in such a way as to limit the usability of the implantable device when subsequently deployed, thereby preventing subsequent use.

Sheathing some implantable devices in a manner that avoids damage to the structural integrity of the stent, to enable subsequent use, can be particularly challenging. For example, some embodiments of stents, such as are disclosed in U.S. patent application Ser. No. 13/153,150, entitled “ESOPHOGEAL STENT,” which is hereby incorporated by reference herein in its entirety, may comprise a support or scaffolding structure formed of a plurality of rows of struts or legs oriented about an outer circumference of the stent and connected by a plurality of connectors extending longitudinally with a longitudinal axis of the stent. Additionally, the stent or other implantable device may comprise a variety of components, and the parameters of these components—such as shape, length, thickness, position, etc.—may greatly vary to provide a stent with certain properties. The arrangement of these components may make sheathing of the stent quite difficult. Protruding components of the scaffolding structure may prevent the stent, or portions of the stent from being “self-sheathing” with traditional equipment. The components may need to be crimped prior to sheathing. Prior to the embodiments of the present disclosure, such embodiments of stents could not be crimped and/or sheathed outside of a factory setting in a manner that would render the stent in a useable state for subsequent deployment and use.

Traditional delivery devices, which require that the implantable device be fully crimped and sheathed prior to storage and/or transport for eventual use, can be problematic to use to deliver (or deploy) a valved stent. A valve of a valved stent may be formed of a polymer material that may be easily deformable by applying a constant force or otherwise maintaining the valve in a deformed state for a prolonged period of time.

For example, embodiments of a valved stent are disclosed in U.S. patent application Ser. No. 13/285,358, entitled “ESOPHOGEAL STENT WITH VALVE,” which is hereby incorporated by reference herein in its entirety, and may include a valve formed of a polymer. Because polymers lack a well defined crystalline structure, they can easily undergo a glass transition at a given glass transition temperature Tgwhen cooled (or heated) and, thereby, exhibit physical properties of both a solid and a liquid. Specifically, a polymer can be cooled into a desired shape and may hold that shape. However, the polymer can easily be reshaped or plastically deformed in response to pressure or stress, particularly if also exposed to temperatures approaching or above the Tgof the polymer. If the Tgis relatively low (e.g., 114 degrees F.), as in the case for some polymers, plastic deformation occurs easily. A polymer valve of a valved stent that is compressed and deformed in a delivery configuration of the stent for a prolonged period of time (e.g., during storage and/or transport) can permanently deform. The deformed valve may not function properly and thus remain in a defective and unusable state. Accordingly, a delivery device that can only be used by a practitioner if the stent arrives fully crimped and/or sheathed may not be an effective delivery device for a valved stent. A delivery device that can be transported with the valve in a natural operable configuration, and not subject to forces that may induce plastic deformation, may be desirable.

Also, because delivery devices are commonly designed to facilitate easy deployment, inadvertent or accidental deployment may easily occur. Safety mechanisms to secure the outer tubular member relative to the inner tubular member typically comprise a pin passing through both the outer tubular member and the inner tubular member. These “pin-type” safety mechanisms can be difficult to operate or even ineffective in some instances. For example, a “pin-type” safety mechanism does not allow distal movement of a trigger and/or an outer sheath to enable sheathing a stent, while also restricting proximal movement of the trigger to prevent inadvertent deployment.

The present disclosure is directed to stent delivery systems addressing various shortcomings of presently available stent delivery devices. In particular, the present disclosure provides a stent delivery system that may enable a practitioner to fully sheath a stent that may be merely partially sheathed or even completely unsheathed and in an expanded configuration. The stent delivery system may have a plurality of triggers and a trigger safety to prevent accidental or inadvertent deployment. A stent delivery system according to the present disclosure may also have a flexible pusher/anchor (“panchor”) component configured to engage the sheathed stent to restrict movement of the sheathed stent both proximally and distally relative to the delivery device.

Although described in terms of delivering an esophageal stent with a valve, a person having ordinary skill in the art, with the aid of the present disclosure, will readily appreciate that the disclosed delivery systems can be used to deliver a variety of crimpable implantable devices, including but not limited to stents, filters, markers, drug delivery devices, valves, and monitors. In one embodiment, the present disclosure provides an esophageal valved stent delivery system. The present disclosure is also applicable to a variety of stents designed for a variety of applications, for example, biliary stents, bronchial stents, tracheal stents, colonic/duodenal stents, and so on. In another embodiment, the present disclosure may provide a heart replacement valve delivery system. In other embodiments, the present disclosure may provide a delivery system for other crimpable valves. In still other embodiments, the present disclosure may provide a delivery system for a variety of crimpable devices.

In some cases, well-known features, structures or operations are not shown or described in detail. Furthermore, the described features, structures, or operations may be combined in any suitable manner in one or more embodiments. As will also be readily understood, the components of the embodiments as generally described and illustrated in the figures herein could be arranged and designed in a wide variety of different configurations.

The terms “proximal” and “distal” refer to opposite ends of a medical device. As used herein, the proximal end of a medical device is the end nearest a practitioner during use, while the distal end is the opposite end. For example, the proximal end of a stent delivery device refers to the end having the handle and disposed nearest a point of contact with the practitioner when the stent delivery device is in use by a practitioner.

FIG. 1is a perspective view of a stent delivery system100in a partially sheathed configuration, according to one embodiment of the present disclosure. The stent delivery system100may comprise a stent delivery device101and a sheathing mechanism201. The stent delivery device101may comprise a trigger assembly102and a tubular member104. The tubular member104is configured to house a crimped and/or sheathed stent10for delivery to a target location within a patient's body, such as within a lumen. The trigger assembly102may enable a practitioner to deploy the stent10. The sheathing mechanism201may enable a practitioner to fully sheath a partially sheathed stent10shortly prior to a procedure in which the stent10may be deployed in a lumen of a patient. In the illustrated embodiment, the stent10may be a valved stent having a valve12. The stent10may have a length, for example, of 100 mm, such that it could be deployed with a two-stage, two-trigger deployment mechanism.

The valved stent10may be an esophageal stent. Some patients suffer from an obstruction of the esophagus at or near the lower esophageal sphincter, which is the valve at the opening of the esophagus into the stomach. The lower esophageal sphincter prevents stomach acid and other gastric fluids from travelling up the esophagus, particularly when a person is lying down or in a prone position. If a stent is positioned near or through the portion of the esophagus where the lower esophageal sphincter is located, the stent may prevent proper functioning of the lower esophageal sphincter. Without a prosthetic valve coupled in the stent to prevent migration of gastric fluids up the esophagus, the gastric fluids can work their way into the lungs, for example, while the person is sleeping. An individual without a properly functioning valve at the opening between the stomach and esophagus can aspirate gastric fluids while sleeping in a recumbent or lying position (e.g., supine, prone, lateral recumbent) and die from asphyxiation. The stent10with a valve12can be positioned at the opening of the esophagus into the stomach and the valve12can function to allow food to pass in one direction but prevent passage of gastric fluids in an opposite direction.

The partially sheathed configuration of the stent delivery system100may be a storage and/or transport configuration. A portion of the stent10may remain uncrimped and/or unsheathed. The valve12may be positioned in an uncrimped and/or an unsheathed portion of the stent10that is in a partially sheathed configuration. The unsheathed portion of the stent10may remain in an uncrimped (or expanded) state. Therefore, the valve can be maintained in an operational or natural (e.g., undeformed) state during, for example, storage and/or transport, until just before implantation of the stent10in a lumen of a patient. Also, the stent10may be partially sheathed to facilitate fully sheathing the stent10to transition to a fully sheathed delivery configuration.

FIG. 2provides a closer perspective view of the stent delivery system100in the fully sheathed delivery configuration. The tubular member104of the stent delivery device101may include an outer sheath126coupled to the trigger assembly102. The outer sheath126may include a pod134at the distal end to enclose or sheathe the stent10in a crimped state. InFIG. 2, the stent10is not shown because it is fully crimped and fully sheathed within the pod134. The trigger assembly102may include a plurality of triggers114,116that are configured to be serially retracted (e.g., pulled) toward a handle106to retract the outer sheath126and provide staged release (or deployment) of the stent10. The triggers114,116may be supported by outer supports110. A proximal trigger114may be pulled proximally, toward the handle106, to partially deploy the stent. A distal trigger116may then be pulled proximally, toward the handle106and the proximal trigger114, to complete deployment of the stent10.

The serial retraction of proximal trigger114and then the distal trigger116to provide a staged deployment of the stent10may occur in a manner such that retracting the proximal trigger114moves the distal trigger116and the outer sheath126proximally and longitudinally relative to an inner member, from a first position to a second position to partially unsheathe and deploy the stent10. Subsequent retraction of the distal trigger116moves the outer sheath126proximally and longitudinally relative to the inner member from the second position to a third position to fully unsheathe and deploy the stent10. Deployment of the stent10will be described in greater detail below with reference to FIGS.8A1-8A2,8B1-8B2,8C1-8C2, and8D.

One or more trigger guide slots150in the outer supports110and corresponding protrusions or trigger guides (not shown) on the triggers114,116may guide longitudinal movement of the triggers114,116. A trigger safety142may inhibit operation of the trigger assembly102to restrict deployment of a sheathed stent10. More specifically, the trigger safety142may limit proximal movement of the proximal trigger114and the distal trigger116, thereby restricting deployment of the stent10. By restricting proximal movement of the triggers114,116, the trigger safety142may guard against inadvertent or accidental deployment of the stent10.

A sheathing grip112may provide a handle that can be grasped during sheathing of the stent10. The sheathing grip112can be grasped with a first hand while the sheathing mechanism201may be grasped with a second hand. With the first hand, the sheathing grip112may be pulled, pushed, or otherwise forced away from the sheathing mechanism201during a sheathing action to crimp and fully sheathe the stent10. Similarly, the second hand may push, pull, or otherwise force the sheathing mechanism201away from the sheathing grip112during a sheathing action.

The sheathing mechanism201is designed for the user to perform a sheathing action to sheathe the stent10. The sheathing action may initiate two actions relative to the stent10. A first action is to crimp the stent10to a diameter that approximates the inner diameter of the pod134. By virtue of crimping, a second action of sliding the pod134over the crimped stent10is facilitated. As can be appreciated, a portion of the stent10, but less than all, may be crimped (or compressed) at a given time and the pod134may be slid over (to sheathe) that portion before or while a next portion of the stent10may be crimped. The crimping action need not be completed for the entire stent10prior to beginning the sliding of the pod134. The stent10can be gradually crimped and the sliding of the pod134may occur as the stent10is crimped, thereby gradually sheathing crimped portions of the stent10. In other words, crimping and sheathing of the stent10may occur contemporaneously, or substantially contemporaneously, in a single motion and/or action.

The sheathing mechanism201may include a sheathing tube202, a sheathing funnel204, sheathing fingers206, a tip insertion funnel208, and a tip132. As will be described in more detail below, the components of the sheathing mechanism201are assembled at a distal end of the tubular member104, around the distal end of the outer sheath126or the pod134, and facilitate sheathing of the stent104. The sheathing funnel204and/or the sheathing tube interact with the sheathing fingers206and/or the stent10to crimp the stent10. The crimping of the stent10compresses the stent10to a crimped configuration over which the pod134can slide.

The sheathing tube202and/or the sheathing funnel204may be a translational member that is axially displaceable relative to the tubular member104of the delivery device100. The translational member may be configured to translate axial movement of the translational member in a distal direction along the tubular member104into radial force to compress and thereby crimp the unsheathed portion of the stent10. For example, the sheathing funnel204may interact with the sheathing fingers206during the sheathing action. The internal taper of the sheathing funnel204may interact with a ramped surface of the sheathing fingers206. The angle of the sheathing fingers206combined with the internal taper of the sheathing funnel204may translate axial movement of the sheathing tube202and sheathing funnel204into a radial force inward that may compress the stent10as the sheathing tube202is advanced distally by the user. As the sheathing funnel204and sheathing tube202advances distally, the stent10is compressed gradually until the stent10is crimped and/or until an outer diameter of the stent10approximates the inner diameter of the stent pod134. A collar205may be disposed within the sheathing tube202and/or sheathing funnel204to engage the sheathing fingers206and thereby facilitate sheathing. Sheathing of the stent10will be described in greater detail below with reference to FIGS.6A1-6A2,6B1-6B2,6C1-6C2, and6D1-6D2.

FIG. 3is an exploded view of the stent delivery system100.FIGS. 4A-4B,4C and4D1-4D2are partially exploded, cut away, and/or cross-sectional side views of the stent delivery system100. Referring collectively to FIGS.3and4A-4B,4C and4D1-4D2, the illustrated stent delivery system100includes a handle106, a rigid support tube108, outer supports110, a sheathing grip112, a proximal trigger114, a distal trigger116, a floater118, an internal connector120, an inner member122, a middle sheath124, an outer sheath126, a pusher/anchor (or panchor, as defined above)128, and a tip132. A pod134may be disposed at, or configured to couple to, the distal end of the outer sheath126to house a sheathed stent10. A sheathing tube202, a sheathing funnel204, sheathing fingers206, and a tip insertion funnel208facilitate sheathing of the stent10into the pod134and/or outer sheath126.

The trigger assembly102, including the triggers114,116, the internal connector120, and the floater118, facilitates deployment of the stent10from a sheathed state within the pod134. More specifically, the trigger assembly102facilitates moving the outer sheath126proximally relative to the inner member122, thereby retracting the pod134from around the stent10to expose and deploy the stent10. Still more specifically, the internal connector120may be bonded to the outer sheath126and proximal movement of the internal connector120relative to the handle106(and relative to the inner member122and outer supports110) may cause proximal movement of the outer sheath126relative to the inner member122. Proximal movement of the outer sheath126relative to the inner member122may result in deployment of the stent10sheathed within the pod134. The triggers114,116allow a practitioner to retract the outer sheath126proximally relative to the inner member122to deploy the stent, as will be explained in greater detail below with reference to FIGS.8A1-8A2,8B1-8B2,8C1-8C2, and8D.

The handle106is configured to be easily grasped by a practitioner to secure and control the stent delivery device101(shown inFIG. 4A). In the illustrated embodiment, the handle106is shaped like the handle or butt of a handgun and configured to position the triggers114,116similar to the position of a trigger of a handgun. The handle106may be ergonomically configured to be comfortably gripped in a practitioner's hand.

The inner member122extends from the handle106, through the trigger assembly102, through the tubular member104, to the panchor128. A distal inner segment136of the inner member122may be coupled to the tip132and configured for later coupling to the panchor132and/or the inner member122at the time of a stent implantation procedure. The distal inner segment136may be an elongate rigid shaft extending from the tip132. The inner member122may be the inner-most component of the stent delivery device101. The inner member122, including the distal inner segment136, may include a lumen and may be configured to receive a guidewire (not shown) that can guide insertion of the tubular member104into a body lumen where the stent10is to be deployed. The inner member122may be formed of a flexible material, such as polyethylene, which can be easily manipulated over a guidewire into a body lumen. In other embodiments, the inner member122may be formed of other flexible materials, including but not limited to nylon, Pebax, polypropylene, and Teflon. The distal segment may be formed of a slightly more rigid material to facilitate insertion through a valve12of the stent10and/or locking or coupling to the panchor128and/or the inner member122.

An inner assembly140(shown inFIG. 4B), which may include the rigid support tube108, the middle sheath124, and the panchor128, may be configured around the inner member122. The rigid support tube108may be securely fixed to the handle106and may be configured to secure a proximal end of the inner member122relative to the handle106. In the illustrated embodiment, the rigid support tube108may be formed of a metal, such as steel, and may be hollow and configured to receive the inner member122. The steel rigid support tube108may then be crimped at one or more points to secure the inner member122inside. In another embodiment the rigid support tube108may be formed of a rigid material, such as plastic, and secured to the inner member122by bonding, gluing, or other manner of affixing or securing the inner member122within or to the rigid support tube108.

The tip132is configured to be positioned at the distal end of the outer sheath126and pod134, when the stent delivery device101is in a fully sheathed delivery configuration and the stent10is fully sheathed. In the illustrated embodiment, the distal inner segment136of the inner member122is coupled to the tip132. The tip132may be bonded to or otherwise connected to the distal inner segment136of the inner member122. The tip132may be formed of a molded plastic. The distal inner segment136may be an elongate shaft configured to extend through the lumen of the stent10to engage the panchor128and/or couple to the inner member122.

In the illustrated embodiment, the tip132and the distal inner segment136are separated from the tubular member104of the stent delivery device101in the partially sheathed configuration (e.g., prior to use of the delivery system100by a practitioner). The distal inner segment136is not typically positioned through a lumen of the stent10and the valve12in the partially sheathed configuration so as to avoid plastic deformation of the valve12. The distal inner segment136may include a connection member138configured to couple to the panchor128. In one embodiment, the connection member138may be a barb configured to mate with an opening within the panchor128. The barb may include a tapered or ramped surface that allows the barb to pass through an opening within the panchor128in one direction and may include orthogonal surfaces that inhibit passage of the barb through the opening within the panchor128in an opposite direction. The opening within the panchor128may include one or more deflectable tabs129configured to deflect (e.g., spread apart) in response to contact with the tapered or ramped surface of the barb of the connection member138. The deflectable tabs129may retract to abut the orthogonal surface(s) of the barb and thereby restrict passage of the barb back out of the opening within the panchor128.

A practitioner can insert the distal inner segment136through the lumen of the stent10, including the valve12, and engage the connection member138into the panchor128just prior to sheathing. The connection member138may be configured such that once the connection member138of the distal inner segment136is inserted into the panchor128the distal inner segment136cannot be removed. In this manner, the tip132is secured into position for sheathing and for the fully sheathed delivery configuration.

The tip132may include a narrow lumen133that connects to a lumen through the distal inner segment136and the lumen of the inner member122to allow a guidewire to be inserted into and through the inner member122. The tip132may be formed in a conical shape, tapering toward the distal end, to lead and guide the tubular member104during insertion into a lumen of the patient's body, for example, the esophagus. The connection member138of the distal inner segment136may couple the distal segment to the panchor128in such a way that the lumen through the distal inner segment136and the tip132aligns with the lumen of the inner member122.

In some embodiments, one or more spacers121a,121b,121c(collectively121) may be positioned around the distal inner segment136of the inner member122and may extend proximally from the tip132to the panchor128. The spacers121may be free floating around (e.g., coaxially with) the distal inner segment136. The spacers121may provide a surface or other support structure against which the panchor128(or segments of the panchor128) may abut to restrict proximal and/or distal movement of the panchor128and panchor segment relative to, for example, the tip132. During sheathing of a stent, for example, forces may be exerted on the stent in a distal direction, which in turn creates forces in a distal direction on the panchor128and the individual segments of the panchor128. The distal forces on the panchor128may cause the panchor segments to tend to separate. The one or more spacers121may restrict and/or prevent separation of panchor segments due to distal forces on the panchor128created during sheathing.

In one embodiment, a first spacer121amay abut with and/or engage the panchor128. The first spacer121amay have an outer diameter sized to allow the first spacer121ato abut and/or engage an inner surface of the panchor128. The second spacer121bmay abut a distal end of the first spacer121aand have an outer diameter that is larger than the outer diameter of the first spacer121a. The larger diameter of the second spacer121bmay enable the second spacer to engage the panchor128and restrict distal movement of the panchor128. More specifically, the second spacer121bmay have an outer diameter large enough to engage an inner surface of a socket portion of the panchor128and thereby prevent a corresponding segment of the panchor128from moving distally, for example relative to the tip132. The third spacer121cmay abut a distal end of the second spacer121band extend distally to abut the tip132and/or an outer tube portion of the distal inner segment136. The third spacer121cmay have an outer diameter similar to the diameter of the first spacer121a. The spacers121may be formed of a rigid material, such as a high yield strength polypropylene, to provide a desired longitudinal rigidity to counteract the forces in the distal direction exerted on the panchor128and/or panchor segments.

The pod134may house the stent10in a crimped configuration or otherwise compressed configuration. In other words, the stent10in a crimped configuration can be sheathed within the pod134. The pod134may be formed of a plurality of sheath layers (collectively131) that may be reflowed to form a solid wall of material. Forming the pod134from a plurality of sheath layers that are reflowed allows a way to bond the pod134to a transition135and maintain constant an outside diameter at a junction between the pod134and the transition135. FIG.4D1provides a side cross-sectional view of a portion of the pod134, the transition135, and the outer sheath126. FIG.4D2provides an enlarged cross-sectional view of the same. In the embodiment shown in FIGS.4D1and4D2, the pod134may comprise three sheath layers131a,131b,131c, an outer sheath layer131a, a mid jacket sheath layer131b, and a liner sheath layer131c. These sheath layers131may form a wall of the pod134. The liner sheath layer131cmay be a 0.005″ polytetrafluoroethylene (PTFE) liner, configured to limit frictional forces between a sheathed stent and an inner surface of the pod134. The mid jacket sheath layer131bmay be 0.005″ 55D Pebax and may provide structural reinforcement to the wall of the pod134. The outer sheath layer may be 0.010″ 55D Pebax. The three layers can be reflowed with heat to fuse or meld them together and make them one solid wall of material.

The transition135may be molded, for example of Pebax, to taper from an outer diameter approximately equal to the outer diameter of the pod134to an outer diameter approximately equal to the outer diameter of the outer sheath126. The outer sheath layer131amay slide over a larger, distal end of the transition135while the mid jacket layer131bmay abut against the distal end of the transition135. When reflowed, the outer sheath layer131a, a mid jacket sheath layer131b, and a liner sheath layer131cmay fuse or meld together and also fuse or meld to the transition135and may form a single integral wall of the pod134.

The panchor128is configured to secure the stent10within the pod134. The panchor128may function as both a pusher and an anchor to restrict movement of the stent both proximally and distally relative to the panchor128. More specifically, the panchor is configured to push against the stent10as a force in a proximal direction is exerted on the stent and configured to anchor the stent10as a force in a distal direction is exerted on the stent10. The panchor128may include one or more annular flanges about an outer circumference of the panchor128. The one or more annular flanges may engage the inner surface of the stent at one or more positions longitudinally along the stent10. In one embodiment, the one or more annular flanges may have five sides, such that an apex between each of the sides is configured to engage an inner surface of the stent10between connectors of the scaffolding structure of the stent10. The panchor128is shown inFIGS. 14A-14H, and will be described in greater detail below with reference to the same.

The middle sheath124is positioned around the inner member122in abutment with the rigid support tube108and the panchor128. The middle sheath124may function as a space-filler between the inner member122and the outer sheath126. By filling the space between the inner member122and the outer sheath126, the middle sheath124can provide additional structural support for the inner member122against buckling, crimping, and other undesired bending and/or collapse of the inner member122and/or the outer sheath126. In particular, pressure on the inner member122created by forces in the longitudinal direction of the inner member122during deployment of a stent can cause the inner member122to buckle, crimp, or otherwise bend in an undesirable fashion. The middle sheath124and the outer sheath126(in abutment with the middle sheath124) provide additional structural support against buckling, crimping or other undesired bending of the inner member122.

The inner assembly140(shown inFIG. 4B) may remain substantially fixed (in the proximal and distal directions) relative to the handle106. The outer sheath126is retracted proximally over the inner assembly140to expose the distal region of the inner assembly140. The trigger assembly102may facilitate proximal retraction of the outer sheath126.

The outer sheath126may substantially encase the inner assembly140, or at least a distal region of the inner assembly140. In the illustrated embodiment, when the stent delivery device101is in the fully sheathed delivery configuration, the outer sheath126may abut a distal portion of the tip132and extend proximally toward a proximal end of the middle sheath124, where the outer sheath126may couple to the internal connector120. As can be appreciated, in other embodiments the outer sheath126may extend proximally to a greater or lesser degree as a function of the positioning of, and/or coupling to, the internal connector120and/or the distal trigger116. The outer sheath126may be formed of a flexible material, such as nylon, which can be manipulated into a body lumen of a patient. In other embodiments, the outer sheath126may be formed of other flexible materials, including but not limited to polyethylene, Pebax, polypropylene, and Teflon.

The outer sheath126may couple to the smaller, proximal end of the transition135, as shown in FIGS.4D1and4D2. The outer sheath126may be formed of, for example, two layers127a,127bof Pebax and may be configured to couple to the proximal end of the transition135similar to the coupling of the pod134to the distal end of the transition135. An outer layer127amay fit over the outer diameter of the proximal end of the transition135while an inner layer127bmay abut against the proximal end of the transition135. The two layers may be reflowed and fused or melded together and to the transition135.

The outer supports110may support and/or provide a housing for the trigger assembly102. The outer supports110may include a plurality of elongate shafts secured to and/or extending from the handle106. The outer supports110may be configured to provide a guide for a plurality of triggers114,116, a housing for the trigger assembly102, and a structure against which the trigger safety142can secure the triggers114,116. In the illustrated embodiment, the outer supports110include an upper outer support110aand a lower outer support110b(collectively110), each configured in a half cylindrical shape. The outer supports110may mate together to form a housing around a portion of the proximal end of the outer sheath126, the internal connector120, the floater118, and a proximal portion of the inner assembly140.

The outer supports110also provide a support structure for the triggers114,116. The triggers114,116may be mounted on and/or positioned around the outside of the outer supports110and are slidably movable, proximally and/or distally relative to the outer supports110. The outer supports110also may be configured to form or otherwise provide one or more trigger guide slots150(shown inFIG. 4A) to restrict rotational movement of the triggers about a longitudinal axis of the outer supports110. The trigger guide slots150also provide a track or guide for the triggers114,116as they move proximally and/or distally relative to the outer supports110. A proximal end of the outer supports110may couple to the handle106and a distal end of the outer supports may couple to the sheathing grip112. The outer supports110may also provide one or more trigger safety notches144configured to be engaged by the trigger safety142to limit proximal movement of the distal trigger116. In the illustrated embodiment, the trigger safety notches144are adjacent to the trigger guide slots150. In another embodiment, one or more trigger safety notches may be positioned separate from the trigger guide slots150.

The sheathing grip112may couple to the outer supports110and may slidably abut against the outer sheath126. The sheathing grip112may be molded of soft Pebax to provide flexibility. The sheathing grip112may be configured to relieve strain on the outer sheath126as the tubular member104is manipulated during insertion into a patient's body. Specifically, the sheathing grip112may be configured to allow the outer sheath126to be displaced at an angle to the outer supports110without kinking the outer sheath126. This translates to allowing the user to position, for example, a distal portion of the outer sheath126at an angle to a main axis of the handle106and triggers114,116without kinking the outer sheath126. If the outer sheath126is kinked, then the stent may not deploy. The strain relief component guards against kinking of the outer sheath. The sheathing grip112may also allow the outer sheath126to slidably move longitudinally for sheathing and deployment of the stent.

The internal connector120may couple the outer sheath126and the distal trigger116. The internal connector120may be a rigid elongate tubular structure. In the illustrated embodiment, one or more protrusions152on the internal connector120near the proximal end extend radially outward to engage the distal trigger116. The internal connector120may be positioned within the housing formed by the outer supports110. A distal portion of the internal connector120may be bonded to or otherwise coupled to the outer sheath126. Accordingly, proximal movement of the internal connector120causes proximal movement of the outer sheath126relative to the inner member122. Proximal movement of the outer sheath126relative to the inner member122results in deployment of a stent10sheathed within the pod134. Similarly, distal movement of the outer sheath126relative to the inner member122causes distal movement of the internal connector120. In one embodiment the internal connector120may be partially inserted into a lumen of the outer sheath126, such that an outer surface of the internal connector120is bonded to an interior surface of the outer sheath126. In another embodiment, the outer sheath126may be received into the lumen of the internal connector120, such that an interior surface of the internal connector120is bonded to an outer surface of the outer sheath126. In still another embodiment, a distal edge of the internal connector120may be bonded to a proximal edge of the outer sheath126. In still other embodiments, a coupling mechanism, such as barbs, a pin, or the like may couple the internal connector120to the outer sheath126.

The internal connector120may further include a floater engagement surface153configured to be engaged by the floater118as it moves proximally relative to the internal connector120. In the illustrated embodiment, the floater engagement surface may be at a proximal end of a floater engagement channel160in the internal connector120. The internal connector120may include a pair of floater engagement channels160configured to receive and guide a pair of barbed prongs176of the floater118. As the barbed prongs176move proximally within the floater engagement channels160, the barbs178may engage the floater engagement surface153. Accordingly, proximal movement of the floater118past a given distance may result in proximal movement of the internal connector120. The given distance past which proximal movement of the floater118results in proximal movement of the internal connector120may be the length of the floater engagement channel160. As can be appreciated, in another embodiment the floater engagement surface153may also be positioned on the distal trigger116.

The distal trigger116may include a ring-shaped base with a pair of finger holds extending radially outward from the outer surface of the base directly opposite one another. The distal trigger116is configured to engage or otherwise couple to the internal connector120. The proximal trigger114may be configured similar to the distal trigger116, having a ring-shaped base and a pair of finger holds extending radially outward from the outer surface of the base directly opposite one another. The proximal trigger114is configured to engage or otherwise couple to the floater118. The proximal trigger114and distal trigger116are shown inFIGS. 10A and 10B, respectively, and described in greater detail below with reference to the same.

The floater118may comprise a tubular shaft having a distal engagement mechanism172and a proximal engagement mechanism174. In the illustrated embodiment, the distal engagement mechanism172may be one or more barbed prongs176at the distal end of the floater118. The barbed prongs176may include outwardly protruding barbs178. The barbs178may be configured to engage the distal trigger116and/or the proximal end of the internal connector120as the floater118is retracted proximally. For example, proximal movement of the floater118past a given distance may result in the barbs178engaging the floater engagement surface153of the internal connector120and in turn may result in proximal movement of the internal connector120. The given distance may be approximately the length of the floater engagement channel160of the internal connector120.

The barbs178may also be configured to allow the floater118to move distally and to telescope into the internal connector120. For example, the barbs178may be configured to slide distally for the length of the floater engagement channel160. The given distance may also be approximately equivalent to the length of the floater118, such that the distal trigger116and internal connector120can be moved proximally relative to the floater118and proximal trigger114a length of the floater118until the distal trigger116is drawn into abutment with the proximal trigger114. This enables serial retraction of the distal trigger116following retraction of the proximal trigger114.

Stated differently, the distal engagement mechanism172may allow the floater to move distally relative to the distal trigger116and the internal connector120(and telescope into the internal connector120). The distal engagement mechanism172may also limit proximal movement of the floater relative to the distal trigger116and the internal connector120because the barbs178of the distal engagement mechanism172engage the internal connector120(at the proximal end) and/or engage the distal trigger116. Described still another way, the distal engagement mechanism172may allow the distal trigger116and the internal connector120to move proximally relative to the floater118(and proximal trigger), such that the distal trigger116can be retracted proximally toward the proximal trigger114to enable serial retraction of the proximal trigger114and distal trigger116. Serial retraction of the triggers114,116will be described in greater detail below with reference to FIGS.8A1-8A2,8B1-8B2, and8C1-8C2.

In the illustrated embodiment, the proximal engagement mechanism174may include a flange or lip around the circumference of the floater118at the proximal end. The proximal engagement mechanism174may be configured to engage a floater engagement ring170(shown inFIG. 10A) of the proximal trigger114, such that proximal movement of the proximal trigger114results in proximal movement of the floater118. Accordingly, proximal movement of the proximal trigger114relative to the handle106and inner member122may result in proximal movement of the floater118, the distal trigger116, the internal connector120, and the outer sheath126, thereby at least partially deploying the stent10. Deployment of the stent10is described in greater detail below with reference to FIGS.8A1-8A2,8B1-8B2,8C1-8C2, and8D.

FIGS. 5A-5Iare perspective views illustrating assembly of a sheathing mechanism201at a distal region of the stent delivery system100ofFIG. 1, sheathing of a stent10, and disassembly of the sheathing mechanism201, preparatory to performing a stent implantation procedure. The delivery device100begins in a partially sheathed configuration inFIG. 5Aand ends in a fully sheathed delivery configuration inFIG. 5I. The components of the sheathing mechanism201are described referring collectively to FIGS.3and5A-5D.

FIG. 5Ais a perspective view of the stent delivery system100illustrating the sheathing tube202and sheathing funnel204disposed over the outer sheath126of the tubular member104. The sheathing tube202may have a tube-like cylindrical shape. The inner diameter of a lumen of the sheathing tube202may be sized and shaped to be positioned over an outer diameter of a distal region of the outer sheath126and/or the pod134of the delivery device101. Furthermore, the sheathing tube202lumen may have an inner diameter configured to allow the sheathing tube202to be slidably moveable relative to the outer sheath126and/or the pod134. In the illustrated embodiment, the sheathing tube202may slide relative to the outer sheath126and relative to the pod134without interference.

The sheathing funnel204may be disposed at a distal end of the sheathing tube202. A proximal end of the sheathing funnel204may be coupled to the sheathing tube202in a manner that the inner diameter of the sheathing funnel204at the proximal end is approximately equivalent to the inner diameter of the sheathing tube202at the distal end. The sheathing funnel204may have an internal taper configured to guide an expanded portion of a stent10and the sheathing fingers206into the sheathing tube202. Accordingly, the distal end of the sheathing funnel204may have an inner diameter that is larger than the inner diameter of the proximal end of the sheathing funnel204and the inner diameter tapers from the distal end to the proximal end.

The sheathing funnel204may include ribs222disposed on an internal surface of the sheathing funnel204and extending in a direction generally from the distal end to the proximal end of the sheathing funnel204. The ribs of the sheathing funnel204are shown in greater detail inFIGS. 12A-12Cand described in greater detail below with reference to the same. The ribs222may interact with the sheathing fingers206to cause the sheathing fingers206to align with the ribs222, such that a flared region212of the sheathing fingers is positioned on either side of each rib222and the ribs are positioned in the gaps between the flared regions212. The ribs also interact with the stent10during sheathing. The sheathing funnel204, and particularly the ribs222, guides the stent10and the sheathing fingers206into the sheathing tube202to crimp the stent10during (or substantially contemporaneous with) sheathing. The crimped stent10can then be drawn into and sheathed within the pod134.

FIG. 5Billustrates the sheathing fingers206assembled and arranged around and/or in engagement with a distal region of the outer sheath126(see e.g.,FIG. 5A) and/or the pod134. The flared portions212of the sheathing fingers206are disposed around the outer diameter of an unsheathed portion of the stent10. The sheathing fingers206, as mentioned, interact with the sheathing funnel204to aid in drawing the stent10into the sheathing tube202to crimp and sheath the stent in the pod134. In the illustrated embodiment, the sheathing mechanism201includes a plurality of sheathing fingers206(e.g., two halves). The sheathing fingers206may each include a base portion214and a flared portion212. The base portions214of the plurality of sheathing fingers206may be configured to couple together to at least partially surround a distal region of the outer sheath126and/or the pod134. The base portions214, when coupled together around the outer sheath126may also be configured to be received into the sheathing tube202, such that the base portions214can be disposed between the outer sheath126(and/or the pod134) and the sheathing tube202.FIG. 5Billustrates the sheathing tube202drawn up around a portion of the base portions214of the sheathing fingers206.

In the illustrated embodiment, a proximal end of the base portions214forms an inner taper configured to abut against a corresponding tapered region at the transition between the outer sheath126and the pod134. The inner taper of the base portions214may limit distal movement of the sheathing fingers206relative to the tubular member104of the stent delivery device101, particularly during sheathing, which may result in pulling the pod134over the compressed stent10.

The flared portions212(FIGS. 3 and 5A) may be configured to extend distally beyond the distal end of the outer sheath126and extend along a length of an unsheathed portion of the stent10beyond a distal end of the stent10. The flared portions214may be arranged circumferentially about an outer diameter of the unsheathed portion of the stent10. The flared portions212may be configured to collapse axially inward, toward a longitudinal axis of the stent10extending through the center of the lumen of the stent10, as the flared portions212of the sheathing fingers206are drawn into the sheathing funnel204and/or sheathing tube202during a sheathing action. As the flared portions212collapse inwardly, they compress the stent10to an outer diameter less than the inner diameter of the pod134. The pod134can then be drawn over the compressed stent10to a fully sheathed delivery configuration.

In the illustrated embodiment, the flared portions212are divided into two elongate projections216forming a gap217in between the projections216. As described, ribs222on an inner surface of the sheathing funnel204may align with the gaps217between the projections216to guide the flared portions212as they are drawn into the sheathing funnel204. The gaps217may allow the flared portions212to collapse and narrow (e.g., reduce the outer diameter) as the projections216are drawn into and received into the sheathing funnel204and sheathing tube202. The distal end of each projection216may include a flange218configured to couple to or otherwise receive the tip insertion funnel208.

FIG. 5Cillustrates the tip insertion funnel208coupled to the distal ends of the sheathing fingers206. In particular, the tip insertion funnel208may be configured to couple to the flanges218(see e.g.,FIG. 5B) at the distal ends of the elongate projections216of the flared portions212of the sheathing fingers206. The tip insertion funnel208tapers from a large distal opening260to a relatively small proximal opening. The tapered shape of the tip insertion funnel208aids to guide insertion of the distal inner segment136of the inner member122as the distal inner segment136is inserted through the valve12of the stent10and into the panchor128. As described above, the valve12may be formed of an easily deformed polymer. The tip insertion funnel208precisely guides the proximal end of the distal inner segment136retrograde through the valve12to avert undesired contact and/or damage, for example, to leaflets of the valve12or other portion of the valve12, as a result of imprecise insertion of the distal inner segment136. The connection member138at the proximal end of the distal inner segment136may be relatively sharp and/or pointed. As can be appreciated, even a relatively small force focused on the relatively narrow point of the connection member138can multiply the force and cause damage to the valve12and/or plastically deform the valve12. The tip insertion funnel208provides a precise guide to properly insert the distal inner segment136through the valve12without causing damage or deformation. The stent delivery system100is in a partially sheathed configuration for storage and/or transport. With the aid of the tip insertion funnel208, the tip132and distal inner segment136can readily be inserted by a practitioner. The tip insertion funnel208is shown in greater detail inFIGS. 15A-15Cand is described below with reference to the same.

FIG. 5Dillustrates the stent delivery system100in a partially sheathed configuration with the tip132and distal inner segment136inserted. The connection member138at the proximal end of the distal inner segment136is inserted through the tip insertion funnel208, through the stent10, including the valve12, and into the panchor128(not visible inFIG. 5D, but seeFIG. 3). The sheathing mechanism201of the stent delivery system100is fully assembled at a distal region of the stent delivery device101. The trigger safety142is positioned to prevent premature full deployment of the partially sheathed stent10before the sheathing process that will fully sheathe the stent. The trigger safety142is positioned in engagement with the first trigger safety notch144a(hidden from view inFIG. 5D, but viewable inFIG. 3andFIG. 4A). During sheathing of the stent, the trigger safety142will transition to the second trigger safety notch144b. The tip insertion funnel208can be detached from the sheathing fingers206prior to sheathing.

FIG.5E1illustrates the tip insertion funnel208removed from the distal ends of the sheathing fingers206, preparatory to sheathing. The tip insertion funnel208may be detached from the flanges218and/or the sheathing fingers206and opened to slide over the inserted tip132.

FIG.5E2illustrates an end view of the distal end of the stent delivery system100with the sheathing mechanism201positioned as in FIG.5E1. The flared portions212of the sheathing fingers206are in a flared state and the flanges218at a distal end of the elongate projections216are extended outward beyond an outer perimeter of the sheathing funnel204. Other components are shown on the drawing for reference.

FIG.5F1illustrates the beginning of a sheathing action. A user, such as a medical practitioner, may grasp in one hand the sheathing tube202and/or sheathing funnel204of the assembled sheathing mechanism201and grasp in the other hand the sheathing grip112of the stent delivery device101. The user may push the sheathing tube202of the sheathing mechanism201forward toward the distal end of the stent delivery system100. In other words, the user may push or otherwise move (displace) the sheathing tube202and sheathing funnel204in a distal direction with the first hand and away from the second hand and the sheathing grip112, while restraining distal movement of the sheathing grip112.

Alternatively and/or in addition, the practitioner can pull the sheathing grip112back in a proximal direction toward the handle106at the proximal end of the stent delivery system100. The sheathing funnel204and/or the sheathing tube202and/or the sheathing fingers206pull the pod134over the crimped stent10. The pod134in turn pulls and moves the outer sheath126, the internal connector120(not visible in FIG.5F1), the trigger safety142, the distal trigger116, the floater118(not visible in FIG.5F1), and the proximal trigger114, all in a distal direction relative to the handle106and the tip132. The displacement also occurs relative to the components of the internal assembly, although the components of the internal assembly are not viewable, including the middle sheath124, the panchor128, the inner member122, and the distal inner segment136. Arrows indicate the direction of the resulting movement relative to the handle106. FIG.5F1illustrates the sheathing tube202and sheathing funnel204moved slightly relative to FIG.5E1. The sheathing funnel204is drawn over the flared portions of the sheathing fingers, including the flanges218. FIG.5F1also illustrates a displacement of the trigger safety142, the distal trigger116and the proximal trigger114.

FIG.5F2illustrates an end view of the distal end of the stent delivery system100with the sheathing mechanism201positioned as in FIG.5F1. The flanges218at a distal end of the elongate projections of the flared portions of the sheathing finger are drawn into and within an outer perimeter of the sheathing funnel204. Other components are shown on the drawing of FIG.5F2for reference.

FIG.5F3is an enlarged sectional view of the sheathing funnel204and/or the sheathing tube202with the flanges218disposed within the sheathing funnel204. Further distal movement of the sheathing tube202and/or sheathing funnel204cause the flanges218to engage against the collar205disposed within the sheathing funnel204and/or the sheathing tube202.

FIG.5G1illustrates another phase of the sheathing action. The sheathing tube202and/or sheathing funnel204are moved distally over the pod134, the stent10, the tip132, and the flared portions216of the sheathing fingers206(not shown in FIG.5G1for clarity). Relative displacement of the sheathing tube202and/or sheathing funnel204can be seen in comparison to FIG.5F1. Pushing the sheathing tube202and/or sheathing funnel204may cause movement of the sheathing tube202and/or sheathing funnel204over the stent10and sheathing fingers206to crimp the stent10and/or collapse the sheathing fingers206inwardly. In addition, movement of the sheathing tube202and/or sheathing funnel204over the stent10and sheathing fingers206may pull the outer sheath126over the crimped stent10. The flanges218of the sheathing fingers206may engage the collar205within the inner surface of the tapered sheathing funnel204and/or the sheathing tube202. The engagement of the flanges218with the collar205may cause the distal movement of the sheathing funnel204and/or the sheathing tube202to move the sheathing fingers206, which in turn move the outer sheath126distally to sheath the crimped stent10.

Again, movement of the outer sheath126relative to the handle may in turn result in displacement of the internal connector120(not visible in FIG.5G1), the trigger safety142, the distal trigger116, the floater118(not visible in FIG.5G1), and the proximal trigger114, all in a distal direction relative to the handle106and the tip132. Arrows indicate the direction of the resulting movement relative to the handle106.

The distal movement of the sheathing tube202and sheathing funnel204collapses the sheathing fingers206, which crimps or compresses the stent10to a diameter smaller than the inner diameter of the pod134. The distal movement of the sheathing tube202and sheathing funnel204also pulls the pod134over the compressed stent10to fully sheathe the stent10. When the trigger safety142reaches a second trigger safety notch144b(FIGS.5E1and5F1), it may make an audible click to indicate that the stent10is fully sheathed and the stent delivery system100is in the fully sheathed delivery configuration. In FIG.5G1, the outer sheath126, the trigger safety142, the distal trigger116, and the proximal trigger114are all shifted distally relative to the handle106. The trigger safety142is positioned to engage the second trigger safety notch144b. Although not visible in the view of FIG.5G1, the internal connector120and the floater118are also shifted distally.

FIG.5G2illustrates an end view of the distal end of the stent delivery system100with the sheathing mechanism201positioned as in FIG.5G1. The flanges218at a distal end of the elongate projections of the flared portions of the sheathing finger are more fully drawn into the sheathing funnel204and are entirely collapsed inward and abutting each other. The flanges218may be engaging the collar205disposed within the sheathing funnel204and/or the sheathing tube202.

FIG.5G3is an enlarged sectional view of the sheathing funnel204and/or the sheathing tube202with the flanges218engaged against the collar205disposed within the sheathing funnel204and/or the sheathing tube202. The collar205causes distal movement of the sheathing funnel204and/or the sheathing tube202to distally displace the sheathing fingers206, thereby distally moving the outer sheath126to sheathe the crimped stent10.

FIGS. 5H and 5Iillustrate disassembly of the components of the sheathing mechanism201(seeFIG. 2), preparatory to an implantation procedure to implant the stent10. InFIG. 5H, the sheathing tube202and/or sheathing funnel204are shown retracted proximally to expose the sheathing fingers206and/or the pod134, such that the sheathing fingers206can be removed. The sheathing fingers206are shown separated and detached from around the pod134. The pod134is slid over an entire length of the stent10, thereby sheathing the stent.

FIG. 5Iillustrates the sheathing tube202and sheathing funnel204pulled over the pod134and tip132and removed from the tubular member104of the stent delivery device101. The stent delivery device101is now in a fully sheathed delivery configuration and ready for use in a procedure to deploy the stent10in a target lumen of a patient needing treatment.

FIGS.6A1-6A2,6B1-6B2,6C1-6C2, and6D1-6D2are cross-sectional views of the stent delivery system ofFIG. 1, at various positions during sheathing of a partially sheathed stent10to transition the stent delivery system100from a partially sheathed configuration to a fully sheathed delivery configuration.

FIG.6A1is a side view of the stent delivery system100in a partially sheathed configuration and a similar configuration as in FIG.5E1. FIG.6A2is an enlarged cross-sectional side view of a distal region of the stent delivery system100. Referring generally and collectively to FIGS.6A1and6A2, the stent delivery system100is prepared for the sheathing process. The tip132and distal inner segment136are inserted into the panchor128and the stent10is partially sheathed within the pod134. The pod134is at position Pspod1and partially enclosing a crimped or compressed portion of the stent10. In other words, the stent10is partially sheathed. The valve12is in an uncompressed, uncrimped, and unsheathed portion of the stent10, such that the valve is in a natural (e.g., undeformed) operable configuration and not subject to forces that may induce plastic deformation. The trigger safety142is engaged around the outer supports110at a first trigger safety notch144a(not visible in FIG.6A1, but see FIG.6B1) at position Pst1. A second trigger safety notch144bis visible. The distal trigger116is positioned adjacent the trigger safety142at position Psd1. The proximal trigger114is positioned at position Psp1substantially in abutment with the handle106and at or toward a proximal end of the one or more trigger guide slots150of the outer supports110.

FIG.6B1is a side view of the stent delivery system100partially through the sheathing process and in a similar position as in FIG.5F1. FIG.6B2is an enlarged cross-sectional side view of the distal region of the stent delivery system100showing the stent10being drawn into and sheathed within the pod134. Referring generally and collectively to FIGS.6B1and6B2, as the sheathing tube202and the sheathing funnel204are moved distally relative to the handle106, the outer sheath126, the trigger safety142, the distal trigger116, and the proximal trigger114also move distally relative to the handle106. The pod134may be slightly displaced from position Pspod1and is now at position Pspod2. The displacement may be due to frictional forces (as depicted) or may be due to the flanges218engaging and being moved by the sheathing funnel204and/or the sheathing tube202. Also, the trigger safety142is displaced from position Pst1to position Pst2, distally toward the second trigger safety notch144b. Similarly, the distal trigger116is displaced distally from position Psd1to position Psd2and the proximal trigger114is displaced from position Psp1to position Psp2. Although not visible in FIG.6B1, the internal connector120and the floater118also move distally. More particularly, the sheathing tube202and sheathing funnel204are pushed distally, in turn pulling the pod134from position Pspod1to position Pspod2, the outer sheath126the internal connector120, the trigger safety142from position Pst1to position Pst2, the distal trigger116from position Psd1to position Psp2, the floater118and the proximal trigger114from position Psp1to position Psp2. The movement of these components may continue until the trigger safety142engages the second trigger safety notch144b. An audible click may be made by the trigger safety142as it engages the second trigger safety notch144b. The first trigger safety notch144ais now visible.

FIG.6C1is a side view of the stent delivery system100at a completion of distal movement of the sheathing tube202and the sheathing funnel204during the sheathing process and in a similar position as in FIG.5G1. FIG.6C2is an enlarged cross-sectional side view of the pod134and the stent10sheathed within the pod134. Referring generally and collectively to FIGS.6C1and6C2, the stent10is fully sheathed. The pod134is now displaced from position Pspod2to position Pspod3. Additional distal displacement of the sheathing tube202and/or sheathing funnel204resulted in abutment of the flanges218with the collar205disposed within the sheathing tube202and/or sheathing funnel204. The collar205in turn transfers force in the longitudinal direction to the flanges218, resulting in longitudinal movement of the sheathing fingers206and movement of the pod134over the crimped stent10from position Pspod2to position Pspod3The distal trigger116and proximal trigger114are also shifted distally in preparation for retraction to deploy the stent10. Specifically, the distal trigger116is now shown displaced distally from position Psd2to position Psd3and the proximal trigger114is displaced from position Psp2to position Psp3. Although not visible in FIG.6C1, the internal connector120and the floater118are also displaced distally. The trigger safety142is displaced from position Pst2to position Pst3in engagement with the second trigger safety notch144bto limit (e.g., prevent) inadvertent deployment of the stent10. The flanges218of the sheathing fingers206are also engaged with the collar205that may be disposed within the sheathing funnel204and/or the sheathing tube202. Accordingly, further distal movement of the sheathing funnel204and/or the sheathing tube202may result in distal movement of the sheathing fingers206, which in turn results in distal movement of the pod134and outer sheath126.

FIG.6D1is a side view of the stent delivery system100in a fully sheathed delivery configuration similar to the configuration inFIG. 5I. FIG.6D1illustrates the sheathing tube202, sheathing funnel204and the sheathing fingers206removed after the sheathing process. FIG.6D2is an enlarged cross-sectional side view of the distal region of the stent delivery system100with the stent10fully sheathed within the pod134. Referring generally and collectively to FIGS.6D1and6D2, the one or more spacers121a,121b,121c(collectively121) can be seen positioned around a portion of the distal inner segment136. The spacers121may be free floating around (e.g., coaxially with) a portion of the distal inner segment136. The spacers121may provide a surface or other support structure against which the panchor128(or segments of the panchor128) may abut to restrict proximal and/or distal movement of the panchor128, or segment thereof, relative to, for example, the tip132. During sheathing of a stent, for example, forces may be exerted on the stent in a distal direction, which in turn may create forces in a distal direction on the panchor128, including individual segments of the panchor128. The distal forces on the panchor128may cause the segments of the panchor128, for example, to tend to separate. The one or more spacers121may restrict and/or prevent separation of panchor segments due to distal forces on the panchor128created during sheathing. The segments of a panchor128are shown inFIGS. 14B-14Eand described below with reference to the same.

In one embodiment, a first spacer121amay abut with and/or engage the panchor128. The first spacer121amay have an outer diameter sized to allow the first spacer121ato abut and/or engage an inner surface of the panchor128. The second spacer121bmay abut a distal end of the first spacer121aand have an outer diameter that is larger than the outer diameter of the first spacer121a. The larger diameter of the second spacer121bmay enable the second spacer to engage the panchor128and restrict distal movement of the panchor128, including individual segments of the panchor128. More specifically, the second spacer121bmay have an outer diameter large enough to engage an inner surface of a socket portion of the panchor128and thereby limit distal movement of a corresponding segment of the panchor128, for example relative to the tip132. The third spacer121cmay abut a distal end of the second spacer121band extend distally to abut the tip132and/or an outer tube portion136bof the distal inner segment136. The distal inner segment136may comprise an outer tube portion136band an inner tube portion136apositioned coaxially within the outer tube portion136b. The outer tube portion136bmay extend a portion of the length of the distal inner segment136and provide a protruding surface (e.g., protruding relative to the inner tube portion) against which the third spacer121acan abut. The inner tube portion136amay extend the length of the distal inner segment136from the tip to the connection member138. The outer tube portion136bmay be bonded to the inner tube portion136a.

FIG. 7Ais a cross-sectional view of the stent delivery system100in the fully sheathed delivery configuration preparatory to use in a medical procedure, prior to the trigger safety142being removed. The trigger safety142is engaged around the outer supports110at the second trigger safety notch144b.FIG. 7Aportrays an interrelation of various components of the stent delivery system100, including but not limited to the handle106, the outer supports110, the floater118, the triggers114,116, the trigger safety142, the internal connector120, the sheathing grip112, the outer sheath126, the middle sheath124, the inner member122, the panchor128, the pod134and the tip132.FIG. 7Bis a close-up cross-sectional view of the stent10in a compressed configuration within the pod134. The panchor128may include an anchor198configured to be positioned between connectors18of the stent10that interconnect annular segments14(or rows of struts16or strut arms) in a scaffolding structure of the stent10. The anchors198may engage the distal ends of the struts16and thereby engage the stent10to limit distal movement of the stent10relative to the panchor128. For example, the anchors198may be arranged radially to be positioned circumferentially between the connectors18. The stent10is compressed around the panchor128and/or the distal inner segment136. The spacers121a,121b,121c, may be disposed between the distal inner segment136and the panchor128and/or the stent10.

FIGS.8A1-8A2,8B1-8B2,8C1-8C2, and8D are side longitudinal cross-sectional views of the trigger assembly of the stent delivery system100, at various positions during deployment of the stent10. FIGS.8A1-8A2,8B1-8B2,8C1-8C2, and8D illustrate operation of the proximal trigger114, the floater118, the distal trigger116, the internal connector120, and the outer sheath126to deploy a stent10.

FIG.8A1shows the stent delivery system100with the trigger safety142removed. The stent delivery system100may be ready to deploy the stent10. The pod134is abutting the tip132at position Pdpod1, completely over and fully enclosing the collapsed stent10. The distal trigger116is positioned substantially at or toward the distal end of the one or more trigger guide slots150(see e.g.,FIG. 2) of the outer supports110at position Pdd1. The proximal trigger114is positioned at position Pdp1. The trigger safety142is removed (and therefore is not shown in FIGS.8A1-8A2,8B1-8B2,8C1-8C2, and8D), thereby allowing retraction of the triggers114,116and deployment of the stent10to occur. FIG.8A2is a close up view of the panchor128engaging the compressed and fully sheathed stent10within the pod134.

FIG.8B1is a side longitudinal cross-sectional view of the stent delivery system100with the proximal trigger114retracted from position Pdp1to position Pdp2. and the stent10partially deployed. Proximal retraction of the proximal trigger114results in proximal retraction of the floater118, which in turn displaces the distal trigger116from Pdd1to position Pdd2. As shown, position Pdd2may be substantially proximate to position Pdp1. Proximal retraction of the distal trigger116may result in proximal retraction of the internal connector120and the outer sheath126. Proximal retraction of the outer sheath126results in at least partial deployment of the stent10. The pod134is shown displaced proximally from position Pdpod1to position Pdpod2, away from the tip132, exposing a portion of the stent10. The stent10, which is expanded in the area exposed outside the pod134, is partially deployed. When the proximal trigger114is fully retracted, a practitioner can more easily reach the distal trigger116. FIG.8B2is a close up view of the partially deployed stent10partially compressed within the pod134.

FIGS.8C1and8C2are side longitudinal cross-sectional views of the stent delivery system100with the distal trigger116fully retracted from position Pdd1to position Pdd3. The floater118is telescoped into the internal connector120. The pod134is completely retracted, from position Pdpod1to position Pdpod3, fully withdrawn from the stent10allowing the stent10to fully expand and deploy.

As described above, the design and coupling of the floater118to the internal connector120(and/or distal trigger116) allow the internal connector120and distal trigger116to move proximally relative to the floater118and the proximal trigger114, thus enabling the two-trigger mechanism of the stent delivery system100. The two-trigger mechanism enables serial retraction of the triggers114,116. A two-trigger design allows an elegant, ergonomic mechanism to enable a practitioner to deploy a longer stent (e.g., a stent with a length longer than the finger span of the practitioner). The two-trigger design also allows a two-stage stent deployment process, enabling repositioning of the stent after partial deployment and before complete deployment. A three-trigger design enables deployment of still longer stents, as described below with reference toFIGS. 16A,16B,17A,17B, and18A-18C. Typically, a maximum trigger reach of a hand of a woman over sixty years of age in the fifth percentile is approximately 3.4 inches. Accordingly, the distance between the triggers and/or handle may be no greater than approximately 3.4 inches. Accordingly, the distance between the triggers and/or handle may be less than approximately 3.4 inches.

FIG. 8Dis a close-up view of the stent10in the fully expanded, deployed state within a lumen of the body. The tip132and distal inner segment136are shown as being partially withdrawn proximally (in the direction of the arrows) through the valve12of the stent10.

FIGS. 9A and 9Bare a transverse cross-sectional view and a longitudinal cross-sectional view, respectively, of a portion of the stent delivery system100.FIG. 9Aprovides a transverse cross-sectional view of the stent delivery system100through the trigger safety142.FIG. 9Aillustrates the nested positioning of the trigger safety142, the outer supports110, the floater118, the rigid support tube108, and the inner member122.

FIG. 9Bprovides a top longitudinal cross-sectional view of the stent delivery system100.FIG. 9Billustrates a number of component relationships, according to one embodiment. Looking from right to left on the figure, the outer sheath126is received into and bonded to an interior surface of the internal connector120. The internal connector120passes through and engages the distal trigger116. Specifically, one or more protrusions152(see e.g.,FIG. 3) extending radially outward from the internal connector120engage the distal trigger116. As shown inFIG. 9B, a first pair of protrusions152aare configured to engage and/or abut a proximal end of the distal trigger116and a second pair of protrusions152bare configured to engage and/or abut a distal end of the distal trigger116. The floater118couples together the proximal trigger114and the internal connector120and distal trigger116. In the illustrated embodiment, the distal engagement mechanism172(FIG. 3) of the floater118engages the internal connector120and the proximal engagement connector174engages the floater engagement ring170(FIG. 10A) of the proximal trigger114. The rigid support tube108extends within the floater118and the internal connector120and around the inner member122.

The trigger safety142is wrapped around or otherwise engages the outer supports110. Inward protrusions188of the trigger safety142engage a trigger safety notch144bformed by the outer supports110to limit proximal movement of the trigger safety142relative to the outer supports110. Alignment ribs189protruding inward from an inner surface of the trigger safety142are received into the trigger guide slots150(see e.g.,FIG. 9A) and align the trigger safety142. The alignment ribs189may also engage a third pair of protrusions152con the internal connector120radiating outward. The engagement of the alignment ribs189with the protrusions152cof the internal connector120limits proximal movement of the internal connector120relative to the trigger safety142and the outer supports, thereby restricting deployment of the stent10. The second pair of protrusions152bmay also be configured to engage alignment ribs189of the trigger safety, such that distal movement of the internal connector120may result in distal movement of the trigger safety142, for example during sheathing of a stent.

FIGS. 10A and 10Bare end views of the triggers114,116of the stent delivery system100ofFIG. 1.FIG. 10Ais an end view of the proximal trigger114andFIG. 10Bis an end view of the distal trigger116.

Referring toFIG. 10A, the proximal trigger114may have a ring-shaped base164and a pair of finger holds166extending radially outward from the outer surface of the base164directly opposite one another. One or more trigger guides168may protrude radially inward from the base164to engage the trigger guide slot150formed by the outer supports110(FIGS. 2,9A). The trigger guides168may restrict rotation of the proximal trigger114about the outer supports110while allowing proximal and distal movement of the proximal trigger114. The proximal trigger114may also include a floater engagement ring170to engage the proximal engagement mechanism174(FIG. 3) of the floater118, such that proximal movement of the proximal trigger114results in proximal movement of the floater118.

Referring toFIG. 10B, the distal trigger116may be configured similarly to the proximal trigger114, having a ring-shaped base154with a pair of finger holds156extending radially outward from the outer surface of the base154directly opposite one another. One or more trigger guides158may protrude radially inward from the base154to engage the trigger guide slot150formed by the outer supports110(FIGS. 2,9A,9B). The trigger guides158may restrict rotation of the distal trigger116about the outer supports110while allowing proximal and distal movement of the distal trigger116. The distal trigger116is configured to engage or otherwise couple to the internal connector120(FIGS. 3,9A,9B).

FIGS. 11A and 11Bare a side view and a top cross-sectional view, respectively, of an internal connector120, a distal trigger116, a floater118, and a proximal trigger114of the stent delivery system100.FIGS. 11A and 11Billustrate the coupling relationship of the internal connector120, the distal trigger116, the floater118, and the proximal trigger114. Referring collectively toFIGS. 11A and 11B, the distal trigger116couples to the internal connector120. In the illustrated embodiment, the one or more outwardly extending protrusions152on the internal connector120mate with the trigger guides158. As the distal trigger116is retracted proximally, toward the handle106, the distal trigger116retracts the internal connector120proximally. Thus, retraction of the distal trigger116results in retraction of the outer sheath126and pod134(FIGS. 2 and 3), which results in at least partial deployment of the stent10.

The proximal trigger114is mechanically coupled to the distal trigger116by the floater118. In the illustrated embodiment, the proximal trigger114further includes a floater engagement ring170coupled to the inwardly protruding trigger guides168(see alsoFIG. 10A). The floater engagement ring170may engage the proximal engagement mechanism174at the proximal end of the floater118, such that proximal movement of the proximal trigger114in turn retracts the floater118. The distal end of the floater in turn engages the distal trigger116and/or the internal connector120. Accordingly, retraction of the proximal trigger114results in retraction of the distal trigger116and/or the internal connector120, which results in at least partial deployment of the stent10.

FIGS. 12A-12Care various views of the sheathing funnel204and sheathing tube202of the stent delivery system100.FIG. 12Ais a perspective view of the sheathing mechanism201disposed at the distal end of a stent delivery device101and showing positioning of the sheathing funnel204and sheathing tube202in the assembled sheathing mechanism201.FIG. 12Bis an end view of the sheathing funnel204andFIG. 12Cis a perspective end view of the sheathing funnel204.

Referring collectively toFIGS. 12A-12C, the sheathing tube202may have a tube-like cylindrical shape. The inner diameter diof a lumen of the sheathing tube202may be sized and shaped to be positioned over an outer diameter of a distal region of the outer sheath126and/or the pod134of the delivery device101. Furthermore, a lumen of the sheathing tube202may have an inner diameter configured to allow the sheathing tube202to be slidably moveable relative to the outer sheath126and/or the pod134. The sheathing tube202may slide relative to the outer sheath126and relative to the pod134without interference. The sheathing tube202may also slide relative to the sheathing fingers206.

The sheathing funnel204may be disposed at a distal end of the sheathing tube202. A proximal end of the sheathing funnel204may be coupled to the sheathing tube202in a manner that the inner diameter of the sheathing funnel204at the proximal end is approximately equivalent to the inner diameter diof the sheathing tube202at the distal end. The sheathing funnel204has an internal taper configured to guide an expanded portion of a stent10and the sheathing fingers206into the sheathing tube202. Accordingly, the distal end of the sheathing funnel204may have an inner diameter that is larger than the inner diameter diof the proximal end of the sheathing funnel204and the inner diameter of the sheathing funnel204may taper from the distal end to the proximal end.

The sheathing funnel204may include ribs222disposed on an internal surface of the sheathing funnel204and extending in a direction generally from the distal end to the proximal end of the sheathing funnel204. The ribs222may be configured to interact with the sheathing fingers206to cause the sheathing fingers206to align with the ribs222such that an elongate projection216of a flared region212of the sheathing fingers206is positioned on either side of each rib222and the ribs222are positioned in the gaps between the flared regions212. The ribs222also interact with the stent10during sheathing. The sheathing funnel204, and particularly the ribs222, guides the stent10and the sheathing fingers206into the sheathing tube202to crimp the stent10during sheathing. The crimped stent10can then be sheathed or drawn into the pod134.

The elongate projections216of the sheathing finger206may include one or more rails219or similar thicker portion disposed on an outer surface and configured to contact the inner surface of the sheathing funnel204and/or sheathing tube202during a sheathing process. The rails219may function to reduce frictional forces between the projections216and the sheathing funnel204and/or sheathing tube202during sheathing of a stent10.

The sheathing funnel204and/or sheathing tube202may include and/or define an annular collar205on an interior surface of the sheathing funnel204and/or sheathing tube202. The collar205may be configured to engage and cause distal movement of the flanges218(at a distal end of the elongate projections216of the flared portion212of the sheathing fingers206) as the sheathing funnel204and/or sheathing tube202is advanced distally over the sheathing fingers206. Engagement of the collar205with the flanges218during distal movement of the collar205may result in distal movement of the sheathing fingers206, resulting in distal movement of the pod134to sheathe the crimped portion of the stent10.

FIGS. 13A-13Care a trigger safety142of the stent delivery system100, according to one embodiment.FIG. 13Ais a perspective view of the trigger safety142.FIG. 13Bis a side view of the trigger safety142in a closed state.FIG. 13Cis a side view of the trigger safety142in an open state.

Referring collectively toFIGS. 13A-13C, the trigger safety142may include an annular body182and a release tab184. The annular body182may be configured to, in a closed configuration, encircle and engage the outer supports110(shown inFIG. 9A). The release tab184releases the annular body182to open the annular body182to allow the annular body182to transition to an open configuration and disengage from the outer supports110and thereby release the trigger safety142. The annular body182may further include various protrusions188and ribs189on an inner surface to engage or otherwise interact with the outer supports110.

The body182may have an annular shape configured to wrap around the outer supports110of the stent delivery device101. The body182may comprise a hinge186to allow the body182to open and disengage from the outer supports110. One or more inward protrusions188may be configured to engage a trigger safety notch144a,144b(shown inFIGS. 3,5F1,6B1, and9B) of the outer supports110.

The protrusions188may each extend inwardly from a deflectable tab187formed in the body182and be designed and configured to allow distal movement of the trigger safety142(for sheathing) while restricting proximal movement of the trigger safety142. Specifically, the trigger safety142, when in an operable state and engaged with the first trigger safety notch144a(see e.g.,FIG. 3), may be moved distally from the first trigger safety notch144ato the second trigger safety notch144b(see e.g.,FIG. 3). The deflectable tabs187may enable the protrusions188to withdraw from engagement with the trigger safety notches144.

The protrusions188may have a ramped distal side configured to interact with a distal edge of the first trigger safety notch144aas the trigger safety142is moved distally. The proximal side of the protrusions may be straight, or unramped, and configured to engage the proximal edge of the trigger safety notches144(see e.g.,FIG. 3) and thereby restrict proximal movement of the trigger safety142relative to the outer supports110. The ramped distal side may act as a ramp to cause the protrusions188to be raised out of engagement with the first trigger safety notch144ain response to distal movement of the trigger safety142relative to the outer supports110. The ramped distal side may interact with a distal edge of the trigger safety notches144, which urges the protrusion out of the trigger safety notch. As the protrusions188rise out of engagement with first trigger safety notch144a, the deflectable tabs187bend or deflect to a deflected state to accommodate the outward shift of the protrusions188.

The deflectable tabs187may be biased toward an undeflected state. When the proximal side of the protrusions188reach the second trigger safety notch144b, the deflectable tabs spring back to the undeflected state causing the protrusions188to engage the second trigger safety notch144band restrict proximal movement of the trigger safety142. The springing back of the deflectable tabs187and the protrusions188may cause an audible click to signal that the stent delivery system100has reached the fully sheathed delivery configuration.

One or more alignment ribs189(or similar protrusions) disposed on the inner surface of the body182are configured to be received in the trigger guide slot150(see e.g.,FIG. 2) to appropriately align the trigger safety142. The ribs189are also configured to engage the protrusions152on the internal connector120(FIGS. 3,9A,9B) and restrict proximal movement of the internal connector120and distal trigger116(see e.g.,FIG. 2). When the internal connector120is unable to move proximally, the floater118(see e.g.,FIGS. 3,9B), the proximal trigger114(FIGS. 3,9B) and the outer sheath126also cannot move proximally. In this manner, the trigger safety142may guard against inadvertent or accidental deployment of a sheathed stent.

Described differently, the ribs189may be configured to restrict movement of the internal connector120(and thus the outer sheath126) relative to the trigger safety142when the annular body182is in the closed configuration around the outer supports110of the stent delivery device101. The protrusions188may be configured to engage the trigger safety notches144of the outer supports110of the stent delivery device101when the annular body is in the closed configuration and restrict proximal movement of the trigger safety142relative to the outer supports110of the delivery device101. The protrusions188in combination with the deflectable tabs187permit distal movement of the trigger safety142relative to the outer supports110of the stent delivery device101to allow distal movement of the outer sheath126relative to the inner member122(and, among other things, the panchor128and the stent10) of the tubular member of the stent delivery device101. The distal movement of the trigger safety142relative to the housing allows the transition of the stent delivery device101from the partially sheathed configuration to the fully sheathed delivery configuration during a sheathing process.

The release tab184of the trigger safety142allows for simple and convenient release of the trigger safety142from engagement around the outer supports110. In the illustrated embodiment, the release tab184is a tongue-like projection extending away from the body182and oriented substantially at a tangent to the ring-like body182. The release tab184may be coupled to the body182by one or more hinged extensions190. The hinged extensions190may include a hinge192to allow the hinged extensions190and the release tab184to rotate away from the body182. The release tab184may engage a projection194on the body182so as to maintain the body182in a closed position. As shown inFIG. 13C, lifting or pulling the release tab184away from the body182may cause the hinged extensions190and the release tab184to rotate away from the body182. As the release tab184rotates away from the body182, the release tab184disengages from the projection194and allows the body182to open. Once the trigger safety142is open, it can be removed from the outer supports110to allow operation of the trigger assembly102.

FIGS. 14A-14Hare views of the panchor128of the stent delivery system100, according to one embodiment of the present disclosure. The panchor includes a base segment230and one or more extension segments232.FIG. 14Ais a perspective view of a base segment230. The base segment230alone can function as a panchor, by itself, according to one embodiment.FIG. 14Bis a perspective view of the panchor128of the stent delivery system100and illustrates an extension segment232coupled to the base segment230.FIG. 14Cis a side view of the panchor128.FIG. 14Dis a top view andFIG. 14Eis a bottom exploded view of the panchor128.FIGS. 14F and 14Gare end views of the panchor128.FIG. 14His a cross-sectional view of the panchor128.

Referring toFIGS. 14A-14H, collectively, the panchor128may include a push surface196and one or more anchors198. The push surface196may be oriented orthogonal to an outer surface of the base segment230. For example, the push surface198may be disposed on a flange positioned annularly around the base segment230. The push surface196is configured to restrict proximal movement of the stent10as the outer sheath126is pulled proximally over the stent10during deployment. The anchors198may include a flange at a distal end of the base segment230and/or the distal end of the one or more extension segments232of the panchor128. In the illustrated embodiment, the anchors198may include a plurality (e.g., five) of protrusions or apices about the circumference of a distal end of the base segment230and/or one or more extension segments232. For example, the anchors198may be a pentagon shaped annular flange having five apices. The protrusions of each anchor198may be configured to be positioned between connectors of the stent10that interconnect annular segments (or rows of struts or strut arms) in the scaffolding of structure of the stent10. For example, the anchors198may be arranged radially to be positioned circumferentially between the connectors of a stent10. The anchors198may engage the distal ends of the struts and thereby engage the stent to limit distal movement of the stent relative to the panchor128.

Engagement of the struts by the anchors198of the panchor128may restrict distal movement of the stent10, so long as the proximal end of the stent10remains sheathed within the pod134and compressed around the panchor128. One or more deflectable tabs129may be positioned at an opening within the panchor128. The deflectable tabs129may be configured to deflect (e.g., spread apart) in response to contact with a tapered or ramped surface of a barb of a connection member that couples the distal inner segment to the distal end of the inner member122(see e.g.,FIG. 3). The deflectable tabs129may retract to abut the orthogonal surface(s) of the barb and thereby restrict passage of the barb back out of the opening within the panchor128, thereby securing the barb in place.

The plurality of segments128, namely the base segment230and one or more extension segments232, may be rotatably and/or flexibly coupled to enable the panchor128to be flexible. In the illustrated embodiment, the segments230,232may comprise ball234and socket236connections. A ball234at a proximal end of the extension segments232fits into and is received by a socket236at the distal end of the base segment230or another extension segment232. The ball234and socket236connection allows the segments230,232to bend and rotate relative to each other. An embodiment of a panchor128having a plurality of extension segments232in a curved configuration is shown inFIG. 18C.

FIGS. 15A-15Care views of a tip insertion funnel208of the stent delivery system ofFIG. 1.FIGS. 15A and 15Billustrate the tip insertion funnel208in a closed state andFIG. 15Cillustrates the tip insertion funnel208in an open state. The tip insertion funnel208may form a large opening260at a distal end that tapers to a small opening262configured to guide the distal inner segment136into the panchor128. Specifically, the tip insertion funnel208may precisely guide the proximal end of the distal inner segment136retrograde through a valve of a stent to avert undesired contact and/or damage, for example, to leaflets of the valve or other portion of the valve, as a result of imprecise insertion of the distal inner segment136.

In the illustrated embodiment, the tip insertion funnel208may comprise two halves242a,242band hinges244at a distal end of the tip insertion funnel208, near the larger distal opening260. The hinges244hingedly couple the halves242a,242btogether. The hinges242may be disposed in a rim246around the outer circumference of the distal opening of the tip insertion funnel208. The hinges242may allow the tip insertion funnel208to open as shown inFIG. 15Cand to be withdrawn over the tip132(see e.g.,FIG. 3) for removal after insertion of the distal inner segment136into the panchor128. The tip insertion funnel208may include removal features248(e.g. finger grips) to aid in removing the tip insertion funnel208. In the illustrated embodiment, a removal feature248is disposed on each of the halves242a,242bon the distal side of the rim246. The removal features are configured to be squeezed together to rotate the halves242a,242brelative to each other about the hinges244to open the tip insertion funnel208.

FIGS. 16A-16Bare perspective views of a stent delivery system1000having three triggers, according to another embodiment of the present disclosure.FIG. 16Ais a perspective view of the stent delivery system1000in a partially sheathed configuration.FIG. 16Bis a perspective view of the stent delivery device1001in a fully sheathed delivery configuration. Referring generally and collectively toFIGS. 16A-16B, the stent delivery system1000has three triggers1002,1004,1006that a practitioner can manipulate to retract an outer sheath1026and pod1034to deploy a stent20. The stent20may have a longer length, for example 150 mm, that may be more easily deployed with a three-stage, three-trigger deployment mechanism.

Other components of the stent delivery system1000may be substantially similar to the components of stent delivery system100described in detail above. The three triggers1002,1004, and1006may be operated sequentially, each to partially deploy the stent20. The first trigger1002may be pulled proximally, toward a handle1008, to partially deploy the stent20. A second trigger1004may then be pulled proximally, toward the handle1008and the first trigger1002, to further deploy the stent20. Finally, a third trigger1006may be pulled proximally, toward the handle1008, the first trigger1002, and the second trigger1004, to complete deployment of the stent20. A trigger safety142may limit proximal movement of the third trigger1006(and also limit proximal movement of the first trigger1002and second trigger1004), thereby restricting deployment of the stent20. The trigger safety142may operate by engaging outer supports1010and an internal connector (not shown) similar to the manner previously described.

The first trigger1002may include an annular base configured to encircle the outer supports1010and one or more finger holds. The first trigger1002couples to the second trigger1004, such that proximal movement of the first trigger1002results in proximal movement of the second trigger1004. The second trigger1004may be substantially similar in structure, function, and/or operation to the proximal trigger114of the stent delivery system100described above. The third trigger1006may be substantially similar in structure, function, and/or operation to the distal trigger116described above. Moreover, the coupling and operation of the second trigger1004and the third trigger1006may be substantially similar to the proximal trigger114and distal trigger116of the stent delivery system100, as described above.

The sheathing mechanism201may be used to sheath the stent20. Sheathing of the stent20, by a sheathing action to transition the stent delivery system1000from the partially sheathed configuration to the fully sheathed delivery configuration, may be accomplished in much the same way as described above. As can be appreciated, the sheathing fingers of the sheathing mechanism201may have a longer length to accommodate a longer stent. Similarly, the sheathing mechanism201may be longer.

FIGS. 17A and 17Bare side and top cross-sectional views, respectively, of an internal connector1020, a third trigger1006, a floater1018, a second trigger1004, floater arms1012, and a first trigger1002of the stent delivery system ofFIGS. 16A and 16B.FIG. 17Ais a side view andFIG. 17Bis a top sectional view illustrating the coupling relationship of the first trigger1002, the second trigger1004, a floater1018, an internal connector1020, and the third trigger1006. The floater1018and internal connector1020may be substantially similar in structure, function, and/or operation to the floater118and internal connector120of stent delivery system100ofFIG. 1, described above. The coupling and operation of the second trigger1004, the floater1018, the internal connector1020, and the third trigger1006may be substantially similar to the corresponding components of the stent delivery system100, as described above with reference toFIGS. 11A and 11B.

Referring collectively toFIGS. 17A and 17B, the third trigger1006couples to the internal connector1020. In the illustrated embodiment, one or more outwardly extending protrusions1052on the internal connector1020mate with trigger guides on the third trigger1006. As the third trigger1006is retracted proximally, toward the handle1008(FIG. 16A), the third trigger1006retracts the internal connector1020proximally. Thus, retraction of the third trigger1006results in retraction of the outer sheath1026and pod1034(FIG. 16A), which results in at least partial deployment of a stent20sheathed within the pod1034.

The second trigger1004is mechanically coupled to the third trigger1006by the floater1018. In the illustrated embodiment, the floater1018engages a floater engagement ring (coupled to inwardly protruding trigger guides) of the second trigger1004. The floater engagement ring engages the proximal end of the floater1018such that proximal movement of the second trigger1004retracts the floater1018. The distal end of the floater engages the third trigger1006and/or the internal connector1020. Accordingly, retraction of the second trigger1004results in retraction of the third trigger1006and/or the internal connector1020, which retracts the outer sheath1026and pod1034and at least partially deploys a sheathed stent20.

The first trigger1002includes one or more barbed external floater arms1012that may extend distally from the base of the first trigger1002to engage the second trigger1004. Barbs1014at the distal end of the external floater arms1012may engage a base of the second trigger1004as the first trigger1002moves proximally, while allowing distal movement of the first trigger1002relative to the second trigger1004. Stated differently, the barbed engagement arms1002allow the second trigger1004to move proximally relative to the first trigger1002, such that the second trigger1004can be operated and retracted toward the first trigger1002, even after the first trigger1002has been retracted.

FIGS. 18A-18Care views of the panchor1028of the stent delivery system1000. The panchor includes a base segment1130and a plurality of extension segments1132a,1132b,1132c,1132d,1132e(collectively1132).FIG. 18Ais a side view of the panchor1028.FIG. 18Bis a side cross-sectional view of the panchor1028.FIG. 18Cis a side cross-sectional view illustrating flexibility of the panchor1028.

Referring toFIGS. 18A-18C, collectively, the panchor1028may include a push surface1096and one or more anchors1098. The push surface1096is configured to restrict proximal movement of the stent20as the outer sheath1026is pulled proximally over the stent20during deployment. The anchors1098may include a flange at a distal end of the base segment1130and/or the distal end of the one or more extension segments1132of the panchor1028. In the illustrated embodiment, the anchors1098may include a plurality (e.g., five) of protrusions or apices about the circumference of a distal end of the base segment1130and/or one or more extension segments1132. The protrusions of each anchor1098are configured to be positioned between connectors of the stent20that interconnect annular segments (or rows) of struts in the scaffolding of structure of the stent20to engage the distal ends of the struts. Engagement of the struts by the anchors1098of the panchor1028restricts distal movement of the stent20, so long as the engaged portion of the stent20remains sheathed within the pod1034and compressed around the panchor1028.

The plurality of segments of the panchor1028, namely the base segment1130and the extension segments1132, may be rotatably and/or flexibly coupled to enable the panchor1028to be flexible. In the illustrated embodiment, the segments1130,1132comprise ball1134and socket1136connections. A ball1134at a proximal end of the extension segments1132fits into and is received by a socket1136at the distal end of the base segment1130or another extension segment1132. The ball1134and socket1136connection allows the segments1130,1132to bend and rotate relative to each other.FIG. 18Cillustrates the panchor1028having a plurality of extension segments1132in a curved configuration.

In the illustrated embodiment, the first extension segment1132amay be slightly longer than the other extension segments1132b,1132c,1132d,1132e. The length of any of the extension segments1132and/or the base member1130may be adjusted according to the design and/or configuration of a stent to be deployed. Moreover, the number of protrusions on the plurality of anchors1098may vary according to the design and/or configuration of a stent to be deployed.

FIG. 19is a perspective view of the stent delivery system100ofFIG. 1packaged in a storage configuration, according to one embodiment.

As can be appreciated, other embodiments are possible in which additional triggers, beyond three, are coupled together in a similar manner as described herein.

The present disclosure may be embodied in other specific forms without departing from its spirit or essential characteristics. The described embodiments are to be considered in all respects only as illustrative and not restrictive. As can be appreciated by those having skill in the art, many changes may be made to the details of the above-described embodiments without departing from the underlying principles of the invention. The scope of the invention is, therefore, indicated by the appended claims rather than by the foregoing description. All changes which come within the meaning and range of equivalency of the claims are to be embraced within their scope.