Plunger apparatus and methods for delivering a closure device

An apparatus for delivering a clip includes an introducer sheath including an outer surface extending between its proximal and distal ends, and a hub on the proximal end that includes spacer elements spaced away from the outer surface. An annular clip includes a plurality of tines extending from its distal end and its proximal end is held away from the outer surface of the sheath by the spacer elements. A handle assembly is attached to the hub that includes an actuator member slidable between the spacer elements and the outer surface of the sheath. The actuator member includes radial protrusions for coupling with the clip, whereby distal movement of the actuator member advances the clip towards the distal end of the sheath. Optionally, a skin overlies the outer surface of the sheath and the clip that is separable from the outer surface as the clip is advanced.

FIELD OF THE INVENTION

The present invention relates generally to apparatus and methods for closing and/or sealing openings through tissue, and more particularly to apparatus and methods for delivering a closure element for closing a puncture in a blood vessel or other body lumen formed during a diagnostic or therapeutic procedure.

BACKGROUND

Catheterization and interventional procedures, such as angioplasty or stenting, generally are performed by inserting a hollow needle through a patient's skin and muscle tissue into the vascular system. A guide wire may then be passed through the needle lumen into the patient's blood vessel accessed by the needle. The needle may be removed, and an introducer sheath may be advanced over the guide wire into the vessel, e.g., in conjunction with or subsequent to a dilator. A catheter or other device may be advanced through a lumen of the introducer sheath and over the guide wire into a position for performing a medical procedure. Thus, the introducer sheath may facilitate introduction of various devices into the vessel, while minimizing trauma to the vessel wall and/or minimizing blood loss during a procedure.

Upon completion of the procedure, the devices and introducer sheath may be removed, leaving a puncture site in the vessel wall. External pressure may be applied to the puncture site until clotting and wound sealing occur. This procedure, however, may be time consuming and expensive, requiring as much as an hour of a physician's or nurse's time. It is also uncomfortable for the patient, and requires that the patient remain immobilized in the operating room, catheter lab, or holding area. In addition, a risk of hematoma exists from bleeding before hemostasis occurs.

Various apparatus have been suggested for percutaneously sealing a vascular puncture by occluding the puncture site. For example, U.S. Pat. Nos. 5,192,302 and 5,222,974, issued to Kensey et al., describe the use of a biodegradable plug that may be delivered through an introducer sheath into a puncture site. When deployed, the plug may seal the vessel and provide hemostasis. Such devices, however, may be difficult to position properly with respect to the vessel, which may be particularly significant since it is generally undesirable to expose the plug material, e.g., collagen, within the bloodstream, where it may float downstream and risk causing an embolism.

Another technique has been suggested that involves percutaneously suturing the puncture site, such as that disclosed in U.S. Pat. No. 5,304,184, issued to Hathaway et al. Percutaneous suturing devices, however, may require significant skill by the user, and may be mechanically complex and expensive to manufacture.

To facilitate positioning devices that are percutaneously inserted into a blood vessel, “bleed back” indicators have been suggested. For example, U.S. Pat. No. 5,676,974, issued to Kensey et al., discloses a bleed back lumen intended to facilitate positioning of a biodegradable plug within a puncture site. This device, however, requires that an anchor of the plug be positioned within the vessel, and therefore, may increase the risk of over-advancement of the plug itself into the vessel.

Alternatively, U.S. Pat. No. 5,674,231, issued to Green et al., discloses a deployable loop that may be advanced through a sheath into a vessel. The loop is intended to resiliently expand to engage the inner wall of the vessel, thereby facilitating holding the sheath in a desired location with respect to the vessel. The loop may also provide a support for facilitating the deployment and deflection of a surgical clip against the vessel wall. Such a device, however, may risk engagement between the loop and the surgical clip, thereby preventing the loop from being withdrawn from the vessel.

Accordingly, apparatus and methods for delivering a device for closing a vascular puncture site or other opening through tissue would be useful.

SUMMARY OF THE INVENTION

The present invention is directed to apparatus and methods for closing and/or sealing openings through tissue, e.g., into body lumens, and more particularly to apparatus and methods for delivering a vascular closure element for closing a puncture in a blood vessel formed during a diagnostic or therapeutic procedure.

In accordance with one aspect of the present invention, an apparatus is provided for delivering a closure element or other annular-shaped device into an opening through tissue, e.g., for engaging tissue adjacent the opening to close and/or seal the opening. The apparatus generally includes an elongate member including proximal and distal ends defining a longitudinal axis therebetween, and an outer surface extending between the proximal and distal ends. In one embodiment, the elongate member may be an introducer sheath that includes a lumen for advancing one or more devices into a body lumen during a procedure.

A carrier assembly may be slidable on the elongate member from the proximal end towards the distal end, the carrier assembly including a carrier member and a pusher member movable distally relative to the carrier member. A distal end of the pusher member may be disposed proximal to a distal end of the carrier member, e.g., if the pusher member has a substantially shorter length than the carrier member, thereby defining a space distal to the pusher member along an outer surface of the carrier member. An annular-shaped element, e.g., a clip or other closure device, may be received on the carrier member, the annular-shaped element being deployable from the carrier member upon distal movement of the pusher member relative to the carrier member.

Optionally, the carrier member may include one or more ramped portions, each portion defining a ramped distal surface and/or a ramped proximal surface. The closure element may include a plurality of tines extending distally, the tines being disposed proximal to the one or more ramped portions such that the ramped portions may protect the tines during advancement of the carrier assembly. In addition, the pusher member may advance the closure element over the one or more ramped portions when the carrier assembly is advanced to a distal position, e.g., for directing the tines radially outwardly to engage surrounding tissue.

A skin overlies at least a portion of the outer surface of the elongate member and the carrier assembly, the skin being separable from the outer surface of the elongate member as the carrier assembly is advanced from the proximal end towards the distal end of the elongate member. In one embodiment, the skin may include a weakened region, e.g., a thin and/or perforated region, extending axially along the skin. The weakened region may be configured to tear preferentially as the carrier assembly is advanced from the proximal end towards the distal end of the elongate member. In another embodiment, the skin may include a flap extending axially along the outer surface of the elongate member and overlying an adjacent region of the skin. The flap may be bonded to the adjacent region such that the flap may be separated from the adjacent region as the carrier assembly is advanced towards the distal end of the elongate member.

In addition or alternatively, the skin may be bonded to the outer surface of the elongate member by an adhesive. The adhesive may have sufficient adhesive strength such that the skin may be peeled away from the outer surface as the carrier assembly is advanced towards the distal end of the elongate member.

The apparatus may also include an actuator assembly including a housing extending from the proximal end of the elongate member, e.g., connectable by cooperating detents, and one or more elongate actuator elements that are movable axially relative to the housing. The actuator elements may be connected to the carrier assembly for coupling movement of the carrier assembly to the one or more actuator elements. For example, the carrier assembly and the actuator elements may include cooperating detents for coupling distal movement of the carrier assembly to the one or more actuator elements as the control member is directed distally. The cooperating detents may release the carrier member upon attaining a distal position, thereby permitting further distal movement of the pusher member to deploy the closure element from the carrier member.

During use, the distal end of the elongate member may be inserted into an opening through tissue, e.g., into a puncture communicating with an artery or other blood vessel. If the elongate member is an introducer sheath, one or more instruments may be inserted through the sheath, e.g., into a blood vessel accessed via the opening. A diagnostic and/or therapeutic procedure may be performed within a patient's body, e.g., via the blood vessel accessed via the opening. Upon completion of the procedure, any instruments may be removed from the sheath, the handle assembly may be connected to the proximal end of the elongate member, and/or an actuator may be coupled to the carrier assembly. Optionally, the distal end of the elongate member may be positioned relative to the blood vessel, e.g., using a bleedback indicator or a tactile indicator, such as an expandable obturator.

To deploy the closure element, the carrier assembly may be advanced towards the distal end of the elongate member. The carrier assembly may cause the skin to separate from the outer surface of the elongate member as the carrier assembly is advanced towards the distal end. If the skin includes a weakened region extending towards the distal end of the elongate member, the weakened region may tear preferentially as the carrier assembly is advanced towards the distal end of the elongate member. If the skin includes a flap extending axially along the outer surface of the elongate member and overlying an adjacent region of the skin, the flap may be released from the adjacent region as the carrier assembly is advanced towards the distal end of the elongate member, thereby allowing the skin to separate from the outer surface. In addition or alternatively, if the skin is bonded to the outer surface of the elongate member by an adhesive, the adhesive may have sufficient adhesive strength to release as the carrier assembly directs the skin outwardly such that the skin is separated from the outer surface as the carrier assembly is advanced towards the distal end.

As the carrier assembly is advanced, the carrier assembly may pass between the skin and the outer surface of the elongate member. Thus, if the opening through tissue extends through one or more layers of fascia or other tissue structures, the skin may facilitate advancing the carrier assembly through the layers and/or minimize the risk of the carrier assembly or the closure element catching on tissue as it is advanced towards the distal end of the elongate member.

The closure element may be deployed from the carrier assembly within the opening, e.g., by ejecting the closure element from the carrier assembly and/or by withdrawing the elongate member from the opening. With the elongate member withdrawn, the closure element may substantially close or seal the opening, e.g., to prevent blood flow therethrough, thereby allowing the opening to heal.

In accordance with another aspect of the present invention, an apparatus is provided for delivering a closure device that includes an elongate member, e.g., an introducer sheath, including proximal and distal ends defining a longitudinal axis therebetween, and an outer surface extending between the proximal and distal ends. A hub may be provided on the proximal end of the elongate member, the hub including one or more alignment tabs or spacers disposed about the periphery of the hub and/or spaced away from the outer surface of the elongate member.

A closure element, e.g., a clip, may be provided that includes a generally annular-shaped body including proximal and distal ends and a plurality of tissue engaging portions extending from the distal end. The proximal end of the closure element may be held away from the outer surface of the elongate member by the one or more spacers.

An actuator or handle assembly is provided that includes an actuator member slidable between the hub and the outer surface of the elongate member. The actuator member includes one or more elements for coupling with the closure element, whereby distal movement of the actuator member advances the closure element towards the distal end of the elongate member. In one embodiment, the hub may include an annular hub defining a passage between the annular hub and the outer surface of the elongate member, e.g., attached to the elongate member by one or more radial spokes. The actuator member may include a tubular member, e.g., defining a “C” shaped cross-section for inserting the tubular member through the passage around the one or more radial spokes.

In a preferred embodiment, the tubular member may include one or more protrusions or tabs, e.g., extending radially outwardly from the distal end of the tubular member. The closure element may include a plurality of pockets for receiving respective tabs on the tubular member therein, thereby coupling the closure element to the tubular member using the tabs. For example, the closure element may include a plurality of alternating diagonal elements extending between the proximal and distal ends of the closure element. The distal end of the closure element may include curved elements connecting adjacent diagonal elements, the curved elements defining the pockets.

Optionally, a skin may overlie at least a portion of the outer surface of the elongate member between the carrier assembly and the distal end of the elongate member, and may at least partially overlie the closure element. The skin may be separable from the outer surface as the closure element is advanced towards the distal end of the elongate member, similar to the previous embodiment.

During use, the distal end of the elongate member may be inserted into an opening through tissue, e.g., into a puncture communicating with a blood vessel, and a procedure may be performed, similar to the previous embodiment. Upon completing the procedure, a distal end of the actuator member may be inserted between the hub and the outer surface of the elongate member. Thus, the actuator member may pass under the spacers, and consequently, under the proximal end of the closure element, until the distal end of the actuator member is coupled with the closure element, e.g., received in pockets adjacent the distal end of the closure element. The actuator member may be advanced distally, thereby advancing the closure element towards the distal end of the elongate member. Tissue adjacent the distal end of the elongate member may be engaged with tissue engaging elements on the closure element, and the elongate member may be withdrawn from the opening, leaving the closure element to close and/or seal the opening. Alternatively, the closure element may be carried by the distal end of the actuator member, rather than being disposed initially adjacent the hub. In this alternative, the closure element may be introduced between the hub and the elongate member when the actuator member is connected to the hub, and advanced along the elongate member as the actuator member is advanced.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Turning now to the drawings,FIGS. 1,2, and4show a first preferred embodiment of an apparatus10for delivering a closure element, such as a clip5, into an opening through tissue for closing and/or sealing the opening (not shown). Generally, the apparatus10includes an introducer sheath12, a housing or carrier assembly14slidably disposed on the sheath12, and a skin44overlying the sheath12and/or carrier assembly14. The apparatus10may also include an actuator or handle assembly16that is connectable to the sheath12. Optionally, as shown inFIG. 4, the apparatus10may also include a locator member or obturator18that may be insertable through the actuator assembly16and/or sheath12for assisting positioning of the apparatus, as described further below.

The sheath12is generally a substantially flexible or semi-rigid tubular member including a lumen20extending along a longitudinal axis28between its proximal and distal ends22,24. The distal end24has a size and shape to facilitate insertion into an opening through tissue (not shown), e.g., having a tapered tip26for facilitating substantially atraumatic introduction through a passage and/or at least partially into a blood vessel or other body lumen accessed via the passage. The lumen20has a size for accommodating insertion of one or more devices therethrough, such as a catheter, guidewire, and the like (not shown). The sheath12may also include a seal (not shown), such as a hemostatic valve, within the lumen20, e.g., at or near the proximal end22, that may provide a fluid-tight seal, yet accommodate inserting one or more devices, such as the obturator18, into the lumen20without fluid passing proximally from the sheath12.

An annular hub30may be provided on the proximal end22of the sheath12, e.g., attached by one or more radial spokes, such as the spoke31shown inFIG. 2. Preferably, the hub30and the sheath12define a “C” shaped passage38(or multiple passages if multiple spokes are provided) therebetween that extends substantially parallel to the longitudinal axis28. In addition, the hub30may include one or more connectors on its proximal end32, such as recesses or pockets34, for cooperating with mating connectors80on the actuator assembly16, as described further below. Alternatively, the actuator assembly16may be connectable directly to the proximal end22of the sheath12(not shown), may be provided as an integral component of the sheath12(not shown), or may otherwise extend from the proximal end22of the sheath12, e.g., such that the hub30may be eliminated.

Optionally, the hub30may include a side port (not shown) that communicates with the lumen20, for example, to allow infusion of fluids into the lumen20through the sheath12. Alternatively, or in addition, the side port may be used to provide a “bleed back” indicator, such as that disclosed in co-pending application Ser. No. 09/680,837, filed Oct. 6, 2000, which is assigned to the assignee of the present invention. The disclosure of this application and any references cited therein are expressly incorporated herein by reference.

In a further alternative, the spokes31may be eliminated from the hub30, and the hub30may be secured to the sheath12by an annular seal or other frictional member (not shown). When the actuator assembly16is attached to the sheath12, as described further below, the hub30may at least partially break away or may be secured to the actuator assembly16. The actuator assembly16and/or the obturator18may frictionally or mechanically become secured to the sheath12to prevent the apparatus10from separating during use.

The carrier assembly14is slidably disposed on an outer surface13of the sheath12and is configured for releasably holding the clip5. The carrier assembly14is slidable from a proximal position, e.g., adjacent the hub30, and preferably at least partially disposed within the passage38, towards the distal end24of the sheath12.

With particular reference toFIG. 2, the carrier assembly14may include an inner or carrier member40and an outer or pusher member42that are nested together and coaxially disposed around the sheath12. The carrier member40is an annular-shaped body including proximal and distal ends46,48, and a ramped region50adjacent the distal end48. The ramped region50may include a ramped proximal surface50a, e.g., for facilitating deployment of the clip5over the ramped region50, and/or a ramped distal surface50b, e.g., for facilitating advancement of the carrier assembly14, as described further below. The distal end48of the carrier member40may be tapered, and/or, alternatively, the carrier member40may include a plurality of ramped regions (not shown) adjacent the distal end48, rather than a single annular ramped region, e.g., spaced evenly about a perimeter or other periphery of the carrier member40.

The carrier member40may include a connector (not shown) on the proximal end46for coupling the carrier member40to the actuator assembly16. Alternatively, the carrier member40may be coupled to the hub30and/or to the proximal end22of the sheath12by a tether or other element (not shown) for limiting distal movement of the carrier member40, as described further below.

The pusher member42may also be an annular body, including proximal and distal ends56,58and may include a connector (not shown) on its proximal end56for coupling the pusher member42to the actuator assembly16. The distal end58may be substantially blunt to engage the clip5, e.g., to advance or deploy the clip5from the carrier assembly14, as described further below. The pusher member42is configured to slidably fit around the carrier member40, but has a substantially shorter length than the carrier member40, such that the carrier and pusher members40,42define a space15distal to the distal end58of the pusher member42and along an outer surface of the carrier member40for receiving the clip5.

The carrier assembly14may be used to deploy a clip5or other closure element from the space15defined by the carrier assembly14. In a preferred embodiment, the clip5is a generally annular-shaped body, including one or more tines7for engaging the tissue around an opening, e.g., adjacent to a wall of a blood vessel (not shown). Preferably, the clip5is configured for drawing the tissue around a puncture in the wall of a blood vessel substantially closed and/or sealed, e.g., for enhancing hemostasis within the puncture. Exemplary embodiments of a closure element for use with an apparatus in accordance with the present invention are disclosed in U.S. Pat. No. 6,197,042, and in co-pending application Ser. Nos. 09/546,998 and 09/610,238, the disclosures of which are expressly incorporated herein by reference.

The carrier assembly14may be actuated from the proximal end22of the sheath12, preferably by the actuator assembly16, as explained further below. The carrier assembly14may be substantially permanently but slidably disposed on the sheath12. For example, the carrier assembly14may be initially stored at least partially within the passage38under the hub30. Alternatively, the carrier assembly14may be provided separate from the sheath12(not shown), e.g., with the clip5pre-loaded therein, but may be slidably attached to the sheath12before deploying the clip5.

The skin44overlies at least a portion of the outer surface13of the sheath12and the carrier assembly14. Preferably, the skin44extends from the carrier assembly14towards the distal end24of the sheath12, e.g., having a proximal end66that at least partially covers the clip5and a distal end68proximate the distal end24of the sheath12. The skin44may be substantially secured over the sheath12, thereby substantially securing the skin44from moving axially relative to the sheath12.

The skin44may be separable from the outer surface13of the sheath12as the carrier assembly14is advanced from its proximal position towards the distal end24of the sheath12. For example, the distal end68of the skin44may terminate adjacent the distal position to which the carrier assembly14may be advanced such that the clip5may be disposed beyond the distal end68of the skin44in the distal position.

The skin44may be substantially inelastic, e.g., such that the skin44may tear when expanded, or alternatively may be elastic. In addition or alternatively, the skin44may include an outer surface70that is substantially slippery to facilitate advancing the sheath12through layers of tissue (not shown), as described further below. The skin44may be formed from a variety of materials, e.g., having sufficient flexibility to allow the carrier assembly14to be advanced between the skin44and the outer surface13of the sheath12and/or sufficient rigidity to allow the skin44to separate or peel away from the outer surface13in a predictable and desired manner. Exemplary materials from which the skin44may be formed include polytetrafluoroethylene (PTFE), polyethylene terephthalate (PET), polyester, latex, silicone, polyamides, polyurethanes, and/or blends and copolymers thereof. The skin44may have a thickness, for example, between about 0.002-0.005 inch. Optionally, the skin44may include fibers (not shown) embedded therein or on a surface thereof that may reinforce the skin44in a desired manner.

The skin44may be bonded to the outer surface13of the sheath12, e.g., using an adhesive, such as an epoxy or urethane. Preferably, the adhesive has sufficient adhesive strength such that the skin44may not slide along the outer surface13of the sheath12, yet may be peeled away from the outer surface13, e.g., as the carrier assembly14is advanced towards the distal end24of the sheath12. Alternatively, the skin44may be thermally bonded to the outer surface13, e.g., by heating the skin44and/or sheath12to at least partially melt or fuse the skin44to the outer surface13.

Alternatively, the skin44may be a tube that is securely received around the outer surface13. For example, the skin44may be a length of shrink tube, having an initial diameter that is substantially larger than the sheath12. The shrink tube may be disposed around the sheath12, heated, and, consequently, shrunk to wrap around or otherwise engage the outer surface13of the sheath12, either with or without adhesive provided between the skin44and the outer surface13.

Optionally, the skin44may include a weakened region72extending between the proximal and distal ends66,68of the skin44, as shown inFIG. 1. The weakened region72may be configured to tear or split preferentially as the carrier assembly14is advanced towards the distal end24of the sheath12. For example, the weakened region72may include a plurality of perforations spaced apart along the skin44, thereby defining a seam extending between the proximal and distal ends66,68of the skin44. Alternatively, the weakened region72may include a relatively thin-walled seam or region (not shown) of the skin44in addition to or instead of the perforated seam.

In a further alternative, fibers (not shown) embedded in the skin44may bias the skin44to tear preferentially in a desired manner. For example, one or more fibers (not shown) may be may be bonded to the skin44that extend between the proximal and distal ends66,68of the skin44, thereby defining a seam adjacent or between the fibers that may tear preferentially. Alternatively, a plastic or other soft material may be bonded over a braided core (not shown) instead of or in addition to individual fibers, e.g., to create regions of the skin44that are resistant to tearing.

Although the weakened region72is shown extending substantially parallel to the longitudinal axis28, the weakened region72may extend helically (not shown) or otherwise between the proximal and distal ends66,68. The term “axially” as used herein is intended to include any arrangement that may extend generally towards the proximal and/or distal ends22,24of the sheath12. When the carrier assembly14is advanced under the skin44, the weakened region72may tear such that the skin44separates or peels away from the outer surface13, as described further below.

Turning toFIG. 3A, in an alternative embodiment, the skin44may be a tubular sleeve44′ that has a relaxed diameter or other periphery that is substantially larger than a diameter or other periphery of the sheath12. The sleeve44′ may be wrapped around the outer surface13of the sheath12until a portion of the sleeve44′ is folded over itself to define a flap45.′ The flap45′ may then be laid over an adjacent region47′ of the sleeve44′, whereupon the flap45′ may be bonded or otherwise fastened in order to secure the sleeve44′ to the sheath12. Thus, as the carrier assembly14(not shown inFIG. 3A) is advanced along the sheath12, the adhesive may fail, and the flap45′ may separate from the adjacent region47′ of the sleeve44′ as the carrier assembly14is advanced towards the distal end24of the sheath12.

Turning toFIG. 3B, in another alternative embodiment, the skin44may be a tubular sleeve44″ that is slitted generally axially such that the sleeve44″ defines first and second portions45″,47″ including edges. When the edges of the first and second portions45″,47″ abut one another, the sleeve44″ defines a diameter or other periphery that is substantially larger than a diameter or other periphery of the sheath12. The sleeve44″ may be wrapped around the outer surface13of the sheath12until the first portion45″ overlies the second portion47.″ The first or outer portion45″ may then be bonded or otherwise fastened to the second or inner portion47″ in order to secure the sleeve44″ to the sheath12. Thus, as the carrier assembly14(not shown inFIG. 3B) is advanced along the sheath12, the adhesive may fail, and the outer portion45″ may separate from the adjacent region47″ as the carrier assembly14is advanced towards the distal end24of the sheath12.

The sleeve44″ may have a substantially uniform thickness about its circumference. Alternatively, the sleeve44″ may have a variable thickness about the circumference. For example, the sleeve44″ may have a relatively thin thickness in the first and second portions45,″47,″ which may provide a more uniform overall cross-section for the skin44, as shown inFIG. 3B.

Returning toFIG. 1, the actuator assembly16generally includes a handle body74and a plurality of telescoping actuator members76,78. The handle body74includes one or more connectors80for connecting the actuator assembly16to the sheath12. For example, the handle body74may include a plurality of tabs80for engaging mating pockets34in the hub30or one or more pockets (not shown) for receiving respective tabs (not shown) on the hub30of the sheath12. Thus, the actuator assembly16may be substantially permanently attached or removably attached to the sheath12by cooperating connectors34,80.

In the preferred embodiment shown, the telescoping actuator members76,78include an inner tubular member76and an outer tubular member78. The tubular members76,78may be substantially rigid members having longitudinal slots therein (not shown), thereby defining generally “C” shaped cross-sections over at least a substantial portion of their lengths. Preferably, the longitudinal slots have a width greater than a width of the spoke(s)31securing the hub30to the sheath12, thereby allowing the tubular members76,78to slide distally beyond the hub30, as described further below. The longitudinal slots may extend predetermined distances from ends of the respective tubular members76,78, e.g., to limit movement of the tubular members76,78in a desired manner, or may extend the entire length of one or both tubular members76,78. Alternatively, the longitudinal slots may be eliminated from the actuator members, such that the actuator members are enclosed wall tubes, if the spokes are eliminated from the hub30(not shown).

The distal ends82,84of the tubular members76,78may include detents (not shown) for engaging respective detents on the carrier assembly14. For example, the detents may be pockets for receiving respective tabs (also not shown) on the carrier and pusher members40,42. Thus, movement of the carrier and/or pusher members40,42may be coupled to the inner and outer tubular members76,78, respectively. Alternatively, the distal ends82,84of the tubular members76,78may simply abut the carrier and pusher members40,42for pushing the carrier and pusher members40,42, thereby coupling distal movement of the carrier and pusher members40,42to the tubular members76,78.

In an alternative embodiment, the tubular members76,78may be replaced with one or more elongate rods, bands, or other actuator elements (not shown) that may extend from the handle body74and may engage, abut, or otherwise be coupled to the carrier assembly14. Preferably, the actuator elements are substantially rigid such that they do not buckle when directed distally against the carrier assembly14. In addition, the actuator elements may be substantially flat such that they slide along the outer surface13of the sheath12, thereby facilitating insertion between the hub30and the sheath12and/or minimizing a cross-sectional profile.

The actuator assembly16also includes a control member, such as a shaft86, that is coupled to the inner and/or outer tubular members76,78. Preferably, the shaft86is connected only to the outer tubular member78, while the inner tubular member76is releasably coupled to the outer tubular member78, as explained further below. Thus, axial movement of one or both of the tubular members76,78may be attained by applying an axial force to the shaft86.

Optionally, the actuator assembly16may also include other components. For example, a lateral port88may include an inner passage89that communicates with an interior region or lumen (not shown) of the telescoped tubular members76,78. Preferably, the lateral port88extends through the slots in the tubular members76,78, although alternatively, separate slots (not shown) may be provided for the lateral port88. The lateral port88may include one or more detents (not shown) for securing the obturator18or other device within the lateral port88, as described below. In addition, the actuator assembly16may include a trigger (not shown) for releasing the obturator18, as described further below.

Turning toFIGS. 4,5A, and5B, the obturator18includes a flexible or semi-rigid tubular body or other elongate rail172having proximal and distal ends174,176. An actuator rod, wire, or other elongate member178is slidably disposed with respect to the rail172, e.g., within a lumen of the rail172. Preferably, the obturator18includes an obturator housing180on the proximal end174. The obturator housing180and/or the proximal end174of the rail172may include one or more detents (not shown) for engaging complementary-shaped detents (also not shown) on the lateral port88of the actuator assembly16. Thus, the obturator18may be substantially secured axially with respect to the lateral port88.

With particular reference toFIGS. 5A and 5B, a distal portion182of the obturator18may include a substantially rounded, soft, and/or flexible distal tip184, possibly including a pigtail (not shown) that may facilitate atraumatic advancement of the distal portion182into a blood vessel or other body lumen (not shown). The obturator18preferably has a length relative to the sheath12such that the distal portion182may extend beyond the distal end24of the sheath12when the obturator18is fully received in the actuator assembly16and sheath12, as shown inFIG. 4.

One or more, and preferably a plurality of, positioning elements186are provided on the distal portion182that may be selectively expanded between a substantially axial collapsed configuration (shown inFIG. 5A) and a substantially transverse expanded configuration (shown inFIG. 5B). Preferably, the positioning elements186are substantially flexible splines configured for expanding substantially transversely with respect to the longitudinal axis28. In one embodiment, shown inFIGS. 5A and 5B, the obturator18includes a pair of splines186disposed generally opposite one another about the distal portion182. Alternatively, the obturator18may include four or any other number of splines (not shown) that are substantially equally spaced about the distal portion182. Additional information on positioning elements that may be used are disclosed in co-pending application Ser. No. 09/732,835, the disclosure of which is expressly incorporated herein by reference.

Optionally, the splines186may include radiopaque markers (not shown) or may be at least partially formed from radiopaque material to facilitate observation of the splines186using fluoroscopy or other imaging systems. Alternatively, or in addition, the carrier assembly14may include one or more radiopaque markers, e.g., at its distal end (not shown) and/or the clip5may include radiopaque marker(s) or may be made from radiopaque material. This may facilitate monitoring the location of the clip5relative to the splines186, as described further below.

Turning toFIGS. 6A-6G, the apparatus10may be used to provide access into a blood vessel or other body lumen90. Preferably, the apparatus10is used to deliver a closure device, such as the clip5, to close and/or seal an incision, puncture, or other opening, such as a passage92that extends from a patient's skin94through intervening tissue96, and a wall98of the vessel90. Alternatively, the apparatus10may be used to deliver other annular shaped devices (not shown) that may be carried by the carrier assembly14.

As shown inFIG. 6A, the sheath12, without the actuator assembly16attached and without the obturator18therein (both not shown), may be inserted or otherwise positioned within the blood vessel90, i.e., through the passage92. The sheath12is preferably provided with the carrier assembly14in its proximal position, e.g., adjacent to or within the hub30. The skin44may facilitate advancing the sheath12through the passage92, e.g., by providing a slippery outer coating on the skin44, e.g., of PTFE. In particular, the skin44may facilitate advancing the sheath12through one or more intervening layers of tissue, such as layers of fascia97, which may otherwise catch on the sheath12.

The sheath12may be advanced over a guide wire or other rail (not shown) previously positioned through the passage92into the blood vessel90using conventional procedures. Preferably, the blood vessel90is a peripheral vessel, such as a femoral or carotid artery, although other body lumens may be accessed using the sheath12, as will be appreciated by those skilled in the art. The passage92, and consequently the sheath12, may be oriented with respect to the vessel90, thereby facilitating introducing devices through the lumen20of the sheath12into the vessel90with minimal risk of damage to the vessel90. One or more devices, such as a guide wire, catheter, and the like (not shown), may be inserted through the sheath12and advanced to a desired location within the patient's body. For example, the devices may be used to perform a therapeutic or diagnostic procedure, such as angioplasty, atherectomy, stent implantation, and the like, within the patient's vasculature.

After completing the procedure, any device(s) may be removed from the sheath12, and the actuator assembly16may be attached to the hub30of the sheath12, as shown inFIG. 6B. The tabs80on the actuator assembly16may be inserted into the pockets34on the hub30of the sheath12(not shown inFIG. 6B), which may align the tubular members76,78such that the distal ends82,84may be inserted freely into the passage38. If the carrier assembly14includes detents (not shown) for being engaged with the distal ends82,84of the tubular member76,78, the detents may become engaged as the tabs80are inserted into the pockets34. Alternatively, the tubular members76,78may be advanced into the passage38by pushing on the shaft86to secure the carrier assembly14to the tubular members76,78. In a further alternative, the distal ends82,84may simply abut the carrier assembly14.

Turning toFIG. 6C, the obturator18may then be inserted into the lateral port88, through the interior of the tubular members76,78and into the lumen20of the sheath12. When the obturator18is fully inserted within the sheath12, the actuator housing180may be received in the lateral port88, and the distal portion182of the obturator18may extend beyond the distal end24of the sheath12. The distal tip184preferably is substantially soft and/or flexible such that the distal portion182substantially atraumatically enters the vessel90. In this fully inserted position, cooperating detents (not shown), e.g., on the actuator housing180and the lateral port88, may be engaged to secure the obturator18axially within the actuator assembly16. Alternatively, the obturator18may be pre-attached to the actuator assembly16, e.g., as a single assembly, as described in co-pending application Ser. No. 10,081,723, filed on Feb. 21, 2002 titled “Apparatus and Methods for Delivering a Closure Element”. The disclosure of this application and any references cited therein are expressly incorporated herein by reference.

As shown inFIG. 6D, the splines186may then be directed to their expanded configuration, for example, by activating a switch (not shown) on the obturator housing180of the obturator18. The sheath12and obturator18may then be moved in conjunction with one another, e.g., by manipulating the actuator assembly16. Preferably, the sheath12and obturator18are together partially withdrawn from the vessel90, until the splines186contact the wall98of the vessel90. Thus, the splines186may provide a tactile indication of the position of the sheath12with respect to the wall98of the vessel90. In addition, the splines186may assist in “presenting” the wall98of the vessel90, e.g., for receiving the clip5(or other closure element) if the clip5is to engage the wall98.

Alternatively, one or more bleed back ports (not shown) may be used to position the sheath12, either instead of or in addition to the obturator18. Such methods are described in U.S. Pat. No. 6,197,042, issued Mar. 6, 2001 or in co-pending application Ser. No. 09/680,837, filed Oct. 6, 2000. The disclosures of these references and any others cited therein are expressly incorporated herein by reference.

Turning toFIG. 6E, with the sheath12properly positioned, the carrier assembly14may be advanced along the sheath12, i.e., into the passage92to deliver the clip5. For example, a distal force may be applied to the shaft86, thereby advancing the tubular members76-80distally over the sheath12. Because the tubular members76,78are coupled to the carrier assembly14, the carrier assembly14advances along the outer surface13of the sheath12as the tubular members76,78are pushed distally.

As the carrier assembly14is advanced towards the distal end24of the sheath12, the carrier assembly14may cause the skin44to separate from the outer surface13of the sheath12. Preferably, the distal end48of the carrier member40includes a ramped region50including a ramped distal surface50b(not shown, seeFIG. 2). The ramped distal surface50bmay slidably engage the skin44, peeling the skin44from the outer surface13of the sheath12and directing the skin44outwardly away from the tines7of the clip5. Thus, the ramped region50may ensure that the tines7of the clip5do not engage the skin44and possibly entangle or tear the skin44in an undesired manner.

If, as shown inFIG. 1, the skin44includes a weakened region72, the weakened region72may tear as the carrier assembly14is advanced and the skin44is forced to expand due to the increased size of the ramped region50. Alternatively, if the skin44is formed from an elastic material, the skin44may simply expand and separate from the outer surface13to accommodate the carrier assembly14passing under the skin44. In a further alternative, as shown inFIGS. 3A and 3B, the skin44may include a flap45′ or outer portion45″ overlying an adjacent region47′,47″ of the skin44. The flap45′ or outer portion45″ may be released from the adjacent region47′,47″ as the carrier assembly14is advanced towards the distal end of the elongate member, thereby allowing the skin44to separate from the outer surface13. If the skin is bonded to the outer surface13of the sheath12by an adhesive, the adhesive may allow the skin44to be peeled away from the outer surface13as the carrier assembly14is advanced towards the distal end24of the sheath12.

Because the carrier assembly14passes beneath the skin44, i.e., between the skin44and the outer surface13of the sheath12, as it advances along the sheath12, the skin44may facilitate advancing the carrier assembly14through one or more intervening layers of fascia97or other tissue. Thus, the distal end48of the carrier member40may not directly contact the layers of fascia97, thereby minimizing the risk of the carrier assembly14and/or the clip5catching or otherwise being held up by the intervening layers of fascia97.

In addition, the tapered configuration of the ramped region50may facilitate advancing the carrier assembly through the passage92substantially atraumatically. Further, because the clip5is substantially covered by the skin44, the tissue surrounding the passage92may not be exposed to the tines7on the clip5, which otherwise may inadvertently catch the tissue and damage the tissue and/or the clip5.

As shown inFIG. 6F, when the carrier assembly14reaches a distal position, the clip5may become at least partially exposed beyond the distal end68of the skin44. In addition, the inner tubular member76may become locked from further distal movement, consequently preventing further distal movement of the carrier member40of the carrier assembly14. Thus, subsequent distal force on the shaft86may cause the pusher member42to advance distally relative to the carrier member40, thereby deploying the clip5from the carrier member40. In a preferred embodiment, the ramped region50includes a ramped proximal surface50athat may deflect the tines7and/or the entire clip5radially outwardly. Thus, the ramped region50may direct the tines7outwardly into surrounding tissue and/or may advance the clip5over the ramped region50and into tissue beyond the distal end24of the sheath12.

In an alternative embodiment, the skin44may cover the clip5in the distal position. As the pusher member42is advanced distally, the clip5may be directed over the ramped region50, thereby causing the tine7to tear through the skin44and into surrounding tissue.

To lock the carrier member40in the distal position, the inner tubular member76may include detents (not shown) that engage with a region of the hub30and/or sheath12to prevent further distal movement. Alternatively, a tether (also not shown) may be coupled to the carrier member76that may prevent further distal movement of the carrier member76beyond the distal position.

Returning toFIG. 6F, the splines186on the obturator18may be collapsed before, during, or after deploying the clip5from the carrier assembly14. Preferably, the splines186automatically return to their collapsed configuration before the clip5is ejected completely from off of the carrier member40. For example, a trigger (not shown) in the actuator assembly16may release a locking mechanism (also not shown) in the actuator housing180, whereupon the actuator housing180may be biased to collapse the splines186. In addition, the obturator18may include a spring or other biasing mechanism to automatically withdraw the distal portion182into the sheath12once the splines186are collapsed. This feature may avoid any risk of contact between the clip5and the splines186, e.g., which otherwise may risk driving the tines7of the clip5through the wall98of the vessel90and into the splines186. Alternatively, the tines7on the clip5may be aligned to extend between the splines186, thereby avoiding any contact between the tines7and the splines186, and the splines186may be collapsed after the clip5is at least partially deployed.

The relative lengths of the tubular members76,78and the sheath12may be selected such that the distal position is at a region proximal to the wall98of the vessel90. For example, it may be desirable to deploy the clip5within intervening tissue between the patient's skin and the wall98of the vessel90. Alternatively, the clip5may be deployed such that the tines7are driven into or through the wall98of the vessel90, as shown inFIGS. 6F and 6G.

Once the clip5is successfully delivered, the apparatus10may be withdrawn from the passage92, leaving the clip5to close the opening in the wall98or otherwise seal the passage92, as shown inFIG. 6G. If the splines64of the locator member14are not automatically collapsed while advancing the housing24, the splines64may be affirmatively collapsed, e.g., by depressing a switch (not shown) on the actuator housing180, either before or after deployment of the clip5. The entire apparatus10may then be removed in one step, or alternatively, the obturator18may first be withdrawn from the sheath12before withdrawing the sheath12, thereby leaving the clip5in place to close and/or seal the passage92. In an alternative embodiment, the distal tip184of the obturator18may be formed from a bioabsorbable and/or expandable material, e.g., collagen, and may be detachable such that the distal tip184may be released within the passage92to enhance sealing.

Turning toFIGS. 7-9, another embodiment of an apparatus210is shown for delivering a closure element, such as a clip205, into an opening through tissue (not shown) for closing and/or sealing the opening. Generally, the apparatus210includes an introducer sheath212, a plunger or actuator assembly216that may be coupled to the sheath212and/or clip205, and a skin244overlying an outer surface213of the sheath212and/or the clip205. Optionally, the apparatus210may also include a locator member or obturator218(not shown, seeFIG. 10) that may be insertable through the actuator assembly216and/or sheath212for assisting positioning of the apparatus, similar to the embodiment described above.

The sheath212is generally a substantially flexible or semi-rigid tubular member including a lumen220extending along a longitudinal axis228between its proximal and distal ends222,224. The distal end224has a size and shape to facilitate insertion into an opening through tissue (not shown), e.g., having a tapered tip226for facilitating substantially atraumatic introduction through a passage and/or at least partially into a blood vessel or other body lumen accessed via the passage. The lumen220has a size for accommodating inserting one or more devices therethrough, such as the obturator218, a catheter, a guidewire, and the like (not shown). The sheath212may also include a seal (not shown) that may provide a fluid-tight seal, yet accommodate inserting one or more devices into the lumen20, similar to the embodiment described above.

An annular hub230is provided on the proximal end222of the sheath212, e.g., attached by one or more radial spokes231. Preferably, the hub230and the sheath212define an annular or “C” shaped passage238between the outer surface213of the sheath212and an inner surface237of the hub230that extends substantially parallel to the longitudinal axis228. The actuator assembly216may be slidably coupled to the hub230, e.g., by inserting the distal end of the actuator assembly216into the passage238. Alternatively, the hub230may include one or more connectors (not shown) on its proximal end232for cooperating with mating connectors (also not shown) on a housing (also not shown) of the actuator assembly216, similar to the embodiment described above. Optionally, the hub230may include a side port (not shown) that communicates with the lumen220, for example, to allow infusion of fluids into the lumen220through the sheath212and/or to provide a “bleed back” indicator, as described above.

The hub230includes a plurality of spacers or alignment tabs234extending from a distal end233of the hub230. Preferably, the tabs234are spaced apart from the outer surface213of the sheath212and extend substantially parallel to the longitudinal axis228. For example, as best seen inFIGS. 9A-9C, an inner surface234aof the tabs234may be aligned with the inner surface237of the hub230such that the tabs234do not obstruct the passage238. In a preferred embodiment, the tabs234are spaced evenly about the circumference of the hub230, e.g., in a desired orientation relative to the passage238, as explained further below. Alternatively, an annular ridge (not shown) may be provided that extends continuously around the circumference of the hub230, thereby defining a single, continuous spacer.

The clip205, best seen inFIG. 8, is an annular-shaped member including proximal and distal ends206,208and a plurality of tissue engaging elements207extending from the distal end208. In a preferred embodiment, the clip205includes a plurality of alternating diagonal elements209extending between the proximal and distal ends206,208. The proximal and distal ends206,208of the clip205include curved elements connecting adjacent diagonal elements209, the curved elements alternating between the proximal and distal ends206,208around the circumference of the clip205such that the clip205defines a substantially continuous serpentine or zigzag pattern about the circumference. Alternatively, the clip may include one or more loops (not shown) between adjacent tissue engaging elements, which may enhance a flexibility of the clip205. Additional information on such a clip may be found in co-pending application Ser. No. 10,081,726, filed on Feb. 21, 2002 titled “Closure Apparatus and Methods for Making and Using Them”. The disclosure of this application and any references cited therein are expressly incorporated herein by reference.

Preferably, the tissue engaging elements are tines207extending distally from the distal end208. Optionally, the tines207or the distal end208may include offset elements204, e.g., on an inner surface thereof for maintaining the tines207away from the outer surface213of the sheath, as best seen inFIGS. 9A-9C. The offset elements204may simply be rounded tabs formed on an inner surface of the clip205, e.g., having a thickness greater than the rest of the clip205or may be separate elements attached to the clip205.

In a preferred embodiment, the tines207are biased towards one another, e.g., for engaging tissue surrounding an opening and drawing the tissue inwardly to substantially close and/or seal the opening. For example, the distal curved elements208of the clip205may be biased to move inwardly and/or the proximal curved elements206may be biased to move outwardly. Thus, in a preferred embodiment, the clip205is biased towards a planar configuration with the tines207directed inwardly towards one another (not shown). Additional information on clips appropriate for use with the apparatus210may be found in application Ser. Nos. 09/546,998 and 09/610,238, incorporated by reference above.

Returning toFIG. 8, the clip205is initially carried adjacent the proximal end222of the sheath212such that the proximal end206of the clip205overlies or engages the tabs234on the hub230, thereby retaining the proximal end206of the clip205away from the outer surface213of the sheath212and in a desired orientation. The spacing of the tabs234on the hub230may correspond to the spacing of the proximal curved elements206of the clip205, e.g., such that each proximal curved element206is held away from the outer surface213of the sheath212by a respective tab234. Preferably, the tabs234hold the clip205in the desired orientation to ensure that the clip205is properly coupled to the actuator assembly216, as described further below. In this initial position, the distal end208of the clip205may rest against the outer surface213of the sheath212, although the tines207may be retained away from the outer surface213by the offset elements204.

The skin244may overlie at least a portion of the outer surface213of the sheath212and the clip205. Preferably, the skin44extends from the clip205towards the distal end24of the sheath12, e.g., having a proximal end266that at least partially covers the clip205and a distal end268proximate the distal end224of the sheath212. The skin244may be substantially secured over the sheath212, thereby substantially securing the skin244from moving axially relative to the sheath212, e.g., by friction and/or by an adhesive, similar to the embodiments described above. In a further alternative, the skin244may be eliminated from any of the embodiments described herein.

The skin244may be separable from the outer surface213of the sheath212as the clip205is advanced from its proximal position towards the distal end224of the sheath212. The skin244may be formed from substantially inelastic materials, e.g., such that the skin244may tear when expanded, or alternatively from elastic materials, similar to the embodiments described above. Optionally, the skin244may include a weakened region (not shown) extending between the proximal and distal ends266,268of the skin244, and/or may include fibers (not shown) embedded in the skin244may bias the skin244to tear preferentially in a desired manner, as explained above.

The actuator assembly216generally includes a substantially rigid tubular member276including proximal and distal ends281,282. In a preferred embodiment, the tubular member276includes a slot284(not shown, seeFIG. 7) extending at least partially between the proximal and distal ends281,282. The tubular member276has a “C” shaped cross-section defining a diameter corresponding generally to the outer surface213of the sheath212and has a thickness such that the distal end282may be slidably inserted into the passage238between the hub230and the sheath212, as explained further below. The slot284may have a width corresponding to the spoke231, thereby allowing the tubular member276to be directed distally through the passage238without substantial interference by the spoke231. Alternatively, the actuator assembly216may include a plurality of substantially rigid bands separated by slots (not shown) that generally define a tubular structure or otherwise conform generally to the shape of the outer surface213of the sheath212.

Optionally, the actuator assembly216may include a housing (not shown) that may be connected to the hub230and/or directly to the proximal end220of the sheath212. The housing may secure the actuator assembly216to the sheath212, may limit movement of the tubular member276, and/or may contain internal components (not shown) of the actuator assembly216, similar to the embodiment described above. In addition, a housing may ensure that the actuator assembly216is coupled to the sheath212in a desired orientation, e.g., to align the slot284of the tubular member276with the spoke231securing the hub230to the sheath212, as explained further below.

The tubular member276includes a plurality of protrusions288on the distal end282for coupling distal movement of the clip205to the tubular member276. Preferably, the protrusions288are tabs that extend radially outwardly from the distal end282of the tubular member276. The protrusions288may be spaced apart about the circumference of the tubular member276, preferably in a predetermined relationship to the tabs234extending from the hub230of the sheath212. Preferably, the protrusions288are disposed between adjacent tabs234such that a protrusion288may be aligned with each distal curved element208of the clip205when the proximal curved elements206are engaged over the tabs234. Thus, the distal curved elements208of the clip205may provide for pockets for receiving the protrusions288to couple the clip205to the tubular member276.

During assembly of the apparatus210, the distal end282of the tubular member276may be aligned with the passage238of the sheath212, as shown inFIG. 7. The distal end282may be inserted into the passage238, as shown inFIG. 9A, until the protrusions288pass between the tabs234, and, consequently, between the proximal curved elements206of the clip205. Thus, as the tubular member276is advanced distally, the protrusions288enter the pockets defined by the distal curved elements208and engage the distal curved elements208of the clip205, as shown inFIG. 9B. With the clip205coupled to the tubular member276, further distal movement of the tubular member276causes the clip205to move distally, as shown inFIG. 9C. As this occurs, the proximal curved elements leave the tabs234and travel along the outer surface213of the sheath212.

If the apparatus210includes a skin244overlying the outer surface213of the sheath212, the skin244may be separated from the outer surface213as the clip205is advanced towards the distal end224of the sheath212, similar to the embodiment described above. In one embodiment, the protrusions288may have a height that is greater than a thickness of the clip205such that the protrusions288extend radially outwardly from the outer surface213of the sheath212a greater distance than the clip205. Thus, the protrusions288may cause the skin244to separate from the outer surface213, thereby minimizing the risk of the tines207of the clip205catching on the skin244. Alternatively, the tines206may be oriented to prevent them from catching on the skin244or the skin244may include an interior surface that is substantially slippery such that the tines207may slide along the skin244.

The apparatus210may be used to deliver the clip205or other closure element, similar to the embodiment described above. Initially, the sheath212, without the actuator assembly216, may be inserted or otherwise positioned within a blood vessel through a puncture or other passage. The sheath212is provided with the clip205in its proximal position, e.g., with the proximal end206held by the tabs234extending from the hub230. The sheath212may be advanced over a guide wire or other rail (not shown) previously positioned through the passage into the blood vessel using conventional procedures. In a preferred method, the blood vessel is a peripheral vessel, such as a femoral or carotid artery, although other body lumens may be accessed using the sheath212, as will be appreciated by those skilled in the art.

One or more devices, such as a guide wire, catheter, and the like (not shown), may be inserted through the sheath212and advanced to a desired location within the patient's body. For example, the devices may be used to perform a therapeutic or diagnostic procedure, such as angioplasty, atherectomy, stent implantation, and the like, within the patient's vasculature. After completing the procedure, any device(s) may be removed from the sheath212, and the actuator assembly216may be inserted into the passage238, as shown inFIGS. 9A and 9B, and as described above. If the actuator assembly216includes a housing (not shown), the housing may be attached to the hub230and/or to the sheath212.

Alternatively, the clip205may be pre-loaded on the actuator assembly216, rather than on the sheath212. For example, the clip205may be disposed on the distal end282such that the protrusions288are disposed between the diagonal elements209and/or the distal curved elements208. In this alternative, the spacers234on the hub230may be eliminated. Thus, the clip205may be advanced through the passage238as the actuator assembly216is coupled to the sheath212. In a further alternative, a pusher member (not shown) may be disposed around the actuator assembly216for deploying the clip205from the actuator assembly216.

As shown inFIG. 10, an obturator218, similar to the obturator18described above, may then be inserted into the lumen220of the sheath212, e.g., through a lateral port (not shown) communicating with the actuator assembly216or the hub230. The distal tip294preferably is substantially soft and/or flexible such that the distal portion292substantially atraumatically enters the vessel. The obturator218may include a plurality of splines296on the distal portion292that are expandable from an axial collapsed configuration to a transverse expanded configuration, such as that shown inFIG. 10. In a preferred embodiment, the splines296are formed from substantially rigid segments, e.g., from stainless steel, connected by hinged regions such that the splines296may bend to the expanded configuration. When the obturator218is fully inserted into the sheath212, the distal portion292extends beyond the distal end224of the sheath212. Cooperating detents (not shown), e.g., on the obturator218and the lateral port, may be engaged to secure the obturator218with respect to the sheath212.

With the obturator218inserted into the sheath212, the splines296may be directed to their expanded configuration, for example, by activating a switch (not shown) on the proximal end of the obturator218. The sheath212and obturator218may then be moved in conjunction with one another and preferably are together partially withdrawn from the vessel90, until the splines296contact the wall98of the vessel90. Thus, the splines296may provide a tactile indication of the position of the sheath12with respect to the wall98of the vessel90. In addition, the splines296may assist in “presenting” the wall98of the vessel90, e.g., for receiving the clip205(or other closure element) if the clip205is to engage the wall98. Alternatively, one or more bleed back ports (not shown) may be used to position the sheath212, either instead of or in addition to the obturator18.

With the sheath212properly positioned, the clip205may be advanced along the sheath212, i.e., into the passage92, as described above. A distal force may be applied to the tubular member276, thereby advancing the clip205distally over the sheath212. As the clip205is advanced towards the distal end224of the sheath212, the protrusions288and/or the clip205may cause the skin244to separate from the outer surface213of the sheath212. Because the clip205passes beneath the skin244, i.e., between the skin244and the outer surface213, as it advances along the sheath212, the skin244may facilitate advancing the clip205through one or more intervening layers, e.g., of fascia (not shown), similar to the embodiment described above.

As shown inFIG. 10, when the clip205reaches the distal end224of the sheath212, the clip205may become at least partially exposed beyond the distal end268of the skin244. Preferably, the clip205is entirely exposed beyond the distal end268of the skin244and the tines207are driven into or otherwise engage tissue adjacent the distal end224of the sheath212. When the clip205is exposed, the clip205may begin to move towards a planar configuration, as shown inFIG. 10, such the proximal curved elements206move away from the distal end282of the tubular member276. The splines296on the obturator218may be collapsed before, during, or after deploying the clip205, and the apparatus210may be withdrawn from the passage92. The clip205may then return to a substantially planar configuration, thereby closing and/or sealing the passage92, similar to the embodiment shown inFIG. 6G.