RELATED APPLICATIONSThe present patent document claims the benefit of the filing date under 35 U.S.C. §119(e) of Provisional U.S. Patent Application Serial No. 62/212,767, filed Sep. 1, 2015, and entitled PROSTHESIS DELIVERY DEVICE, which is hereby incorporated by reference.
BACKGROUNDThe present disclosure relates generally to medical devices, and more particularly, to a system and methods for placement and deployment of a prosthesis in a vessel lumen.
The use of delivery devices or introducers employing catheters has long been known for a variety of medical procedures, including procedures for establishing, re-establishing or maintaining passages, cavities or lumens in vessels, organs or ducts in human and veterinary patients, occlusion of such vessels, delivering medical treatments, and other interventions. For these procedures, it has also long been known to deliver an implantable medical device by means of a catheter, often intraluminally. For example, a stent, stent-graft, vena cava filter or occlusion device may be delivered intraluminally from the femoral artery, via a transapical approach and/or using other acceptable delivery locations and methods for deployment of the prosthesis.
For procedures in which a prosthesis or other medical device is implanted into a patient, the prosthesis to be implanted is normally held on a carrier catheter or cannula of the introducer in a compressed state and then released from the cannula so as to expand to its normal operating state, prior to withdrawal of the cannula from the patient to leave the implant in position. In many devices, the steps to carry out the implantation may occur, for example, first by retracting a retractable sheath to expand or partially expand the prosthesis, and then performing further steps to, for example, release one or both ends of the prosthesis, deploy an anchoring stent, or the like.
The prosthesis which is to be implanted within a patient's vasculature by the delivery device may vary depending on various factors including the procedure being performed and the portion of the vasculature being treated. The delivery device described herein can be configured to deploy a wide range of different prostheses including, but not limited to cuffs, single lumen tubular stent grafts, bifurcated AAA stent grafts, branched or fenestrated stent grafts and combinations thereof. In addition to facilitating the delivery of a wide range of prostheses, the delivery device can be used for a variety of delivery approaches to be utilized, including but not limited to transapical or femoral approaches.
While the embodiments disclosed herein may be generally discussed in relation to a delivery device for a stent graft and method of deployment thereof into one or more specific arteries, including the aorta and iliac arteries, it is also contemplated that the present disclosure is not so limited and may relate to any prosthesis and/or any body or vessel lumen in which such a deployment is necessary or desired.
BRIEF SUMMARYIn one aspect, a system for the delivery and deployment of a prosthesis comprises a delivery device having a distal end and a proximal end. The delivery device comprises an inner cannula extending between the distal end and the proximal end of the delivery device, a positioner disposed coaxially over a first portion of the inner cannula, a concentric cannula disposed coaxially over a second portion of the inner cannula, and a tip assembly disposed over a third portion of the inner cannula. A distal end of the concentric cannula is attached to a proximal end of the positioner. The tip assembly comprises a distal tip segment and a proximal tip segment disposed proximally of the distal tip segment, the distal tip segment being attached to a proximal end of the concentric cannula, the proximal tip segment being attached to a proximal end of the inner cannula. A prosthesis is carried on the concentric cannula at the proximal end of the delivery device and a sheath is mounted coaxially over the prosthesis. The sheath comprises a split defining a proximal sheath segment disposed proximally of the split and a distal sheath segment disposed distally of the split. A proximal end of the proximal sheath segment is attached to the proximal tip segment.
In another aspect, a prosthesis fixation system comprises a delivery device having a distal end and a proximal end, the delivery device comprising an inner cannula extending between the distal end and the proximal end of the delivery device, a positioner disposed coaxially over a first portion of the inner cannula, and a tip assembly attached to a proximal end of the inner cannula. Further, the prosthesis fixation system comprises a prosthesis releasably coupled to the delivery device at the proximal end of the delivery device, at least one trigger wire extending longitudinally within a lumen of the positioner, and at least one suture loop attached to the proximal end of the positioner. A proximal end of the at least one trigger wire extends proximally beyond the proximal end of the positioner such that the at least one trigger wire passes through the at least one suture loop and is removably attached to an end of the prosthesis for releasably coupling the end of the prosthesis to the delivery device.
BRIEF DESCRIPTION OF THE DRAWINGSFIG. 1 is a rear perspective view of one example of a delivery device illustrating a split sheath deployment system with a divided tip for placement and deployment of a prosthesis at the proximal end of the delivery device.
FIG. 2 illustrates the proximal end of the delivery device and the prosthesis fully sheathed.
FIG. 3 illustrates the proximal end of the delivery device and the prosthesis partially unsheathed.
FIG. 4 illustrates the proximal end of the delivery device and the proximal end of the prosthesis fully unsheathed.
FIG. 5 illustrates the proximal end of the delivery device and the prosthesis fully unsheathed.
FIG. 6 illustrates the proximal end of the delivery device and the prosthesis fully deployed.
FIG. 7 illustrates the proximal end of the delivery device and the delivery device partially withdrawn after the prosthesis is fully deployed.
FIG. 8 is a cross-sectional side view of the proximal end of the delivery device and the prosthesis fully sheathed.
FIG. 9 is a cross-sectional side view of the proximal end of the delivery device and the proximal end of the prosthesis fully unsheathed.
FIG. 10 is a cross-sectional side view of the proximal end of the delivery device and the prosthesis fully unsheathed.
FIG. 11 is a perspective view of the proximal end of the delivery device and the prosthesis fully sheathed.
FIG. 12 is a perspective view of the proximal end of the delivery device and the prosthesis fully unsheathed.
FIG. 13 is a perspective view of the proximal end of the delivery device illustrating the delivery device partially withdrawn after the prosthesis is fully deployed.
FIG. 14 illustrates an example of an attachment and release mechanism for the distal end of the prosthesis.
FIG. 15 illustrates another example of an attachment and release mechanism for the distal end of the prosthesis.
FIG. 16 is an end view of one example of a positioner with suture loops for the delivery device.
FIG. 17 illustrates an example of an attachment and release mechanism for the proximal end of a prosthesis.
DETAILED DESCRIPTIONIn the present disclosure, when referring to a prosthesis delivery device, “proximal” refers to the part of the delivery device that is furthest from the operator of the delivery device and intended for insertion in a patient's body and “distal” refers to that part of the delivery device closest to the operator. With regard to a prosthesis, the term “proximal” refers to that part of the prosthesis that is closest to the proximal end of the delivery device and “distal” refers to the opposite end of the prosthesis. The term “ipsilateral” is used to indicate that the diseased vessel(s) being accessed during a given procedure are on the same side of the body (right or left) as the vascular access delivery device/introducer, while “contralateral” signifies that the vessel(s) of interest are on the opposite side of the body.
Referring initially toFIG. 1, an example of a delivery device is shown generally at2, including aproximal end4 and a distal end6. Ahandle assembly8 is located adjacent the distal end of the device. A split sheath deployment system with a divided tip can be operated and manipulated using thehandle assembly8, as will be described in further detail below.
In one example, thehandle assembly8 generally includes first ormain handle10, a second orfront handle12 and a third orrear handle14. Themain handle10 is fixed relative to thedelivery device2. In one example, themain handle10 may also be fixed relative to thefront handle12 and/or to therear handle14, with thefront handle12 and therear handle14 being separately and independently rotatable relative to themain handle10. Further details of examples of a handle assembly that may be used to manipulate the split sheath and divided tip assembly are described herein and in U.S. Provisional Application Nos. 62/064,595 filed on Oct. 16, 2014, which application is incorporated by reference herein in its entirety.
As shown inFIGS. 2-13, theproximal end4 of thedelivery device2 includesretention region16 upon which a variety of prostheses52 can be releasably coupled and a “divided” tip assembly ornose cone dilator18. Thetip assembly18 includes aproximal tip segment20 having a forward proximal taper and aninner lumen20aand a separatedistal tip segment22 having a reverse distal taper and aninner lumen22a,as shown for example inFIGS. 8-10. Thetip assembly18 presents a smooth tapered surface to facilitate entry into and movement through a body vessel and facilitates deployment of the prostheses52, as will be described in further detail below.Tip assembly18 may include radiopaque material or be equipped with a radiopaque marker (not shown) to facilitate visualization of thetip assembly18 in use provided by desired imaging modality (i.e., by fluoroscopy, MRI,3D or other imaging techniques).
Aninner cannula26 extends the longitudinal length of thedelivery device2, from apin vice24 at the distal end6 of thedevice2 to thetip assembly18 at theproximal end4 of thedevice2. Theinner cannula26 may be connected at its distal end within thehandle assembly8 to facilitate pushing the inner cannula forward or proximally relative to thedevice2, as described further herein. At its proximal end, theinner cannula26 is moveably received within theinner lumen22aof thedistal tip segment22 and is fixedly attached within theinner lumen20aof theproximal tip segment20. More particularly,inner cannula26 extends within theinner lumen22aof thedistal tip segment22, which may be configured so as to allowinner cannula26 to move or slide longitudinally therein.Inner cannula26 also extends within theinner lumen20aof theproximal tip segment20, and may be attached or coupled to theproximal tip segment20 by various means, including adhesives, welding, and/or other suitable attachment mechanism. In one example,inner cannula26 is attached to theproximal tip segment20 by an overmolding process and a gluing process. As a result, pushing theinner cannula26 in a proximal direction simultaneously causes proximal longitudinal movement of theinner cannula26 as well as proximal movement of theproximal tip segment20 of thetip assembly18.Inner cannula26 has aninner lumen26awhich may accommodate aguide wire28 for tracking thedelivery device2 to a desired position within a patient's vasculature and which may also be used for flushing or injection of fluids as shown inFIG. 3. Theinner cannula26 may be made of a variety of suitable materials that are stiff, yet flexible enough to allow theinner cannula26 to conform to the tortious anatomy of a patient during use, and may be either straight or have a curve imparted to a portion of it. For example, theinner cannula26 may be constructed of polymers, metals and/or alloys, including nitinol or stainless steel.
A stiffening cannula orpositioner30, sometimes also referred to as a pusher, is disposed coaxially over at least a portion of theinner cannula26. Thepositioner30 may be a cannula constructed from various materials, and in one example, a proximal portion of the positioner which is introduced into the patient may comprise a polymer, sometimes referred to as VRDT (or vinyl radiopaque dilator tubing), plastics, metals, alloys or a combination thereof, whereas a distal portion of thepositioner30 may comprise the same material as the proximal portion of thepositioner30 or it may be a different material including but not limited to plastics, polymers, alloys, metals or a combination thereof, that provide sufficient maneuverability and stiffness to thepositioner30 as necessary and desired. Thepositioner30 may extend from a location just distal of theprosthesis retention region16 coaxial with a length of theinner cannula26 and terminate at a distal end within thehandle assembly8. In one example, the distal end of thepositioner30 may be directly or indirectly attached to themain handle10 by various means, including threaded attachment, adhesives, welding, and/or other suitable attachment mechanisms. For a length of thepositioner30, a stiffening rod (not shown) may be disposed over theinner cannula26 and/or over thepositioner30 for additional stability and maneuverability.
Aconcentric cannula34 may be disposed coaxially over a portion of theinner cannula26 at theprosthesis retention region16. Adistal end36 of theconcentric cannula34 may be attached or coupled to aproximal end32 of thepositioner30 by various means, including adhesives, welding, and/or other suitable attachment mechanisms. Aproximal end38 of theconcentric cannula34 may be attached or coupled to thedistal tip segment22 of thetip assembly18 by various means, including adhesives, welding, and/or other suitable attachment mechanisms. Theconcentric cannula34 may be constructed from various materials including but not limited to plastics, polymers, alloys, metals or a combination thereof, that provide sufficient maneuverability and stiffness to theconcentric cannula34 as necessary and desired. In one example,concentric cannula34 may be constructed of a flexible, high-tensile polymeric material such as polyetheretherketone (PEEK).
Thedelivery device2 can be used to deliver and deploy a wide variety of prostheses52, including variously sized and shaped stent grafts. Therefore,FIG. 1 illustrates one exemplary prosthesis52 in dashed lines to indicate that it is a generic prosthesis for illustrative purposes and that any one or more different prostheses can be interchanged and be releasably coupled to thedelivery device2 in a similar fashion. Several non-limiting examples of prostheses52, which may be delivered to and deployed within a patient in a controlled and sequential manner using thedelivery device2, are described further herein.
As shown inFIGS. 2-13, the prosthesis52, such asstent graft54, is carried on thedelivery device2 at theproximal end4. More specifically, the prosthesis52, such asstent graft54 is carried on theconcentric cannula34 at theprosthesis retention region16. In one example, astent graft54 has an uncoupled state in which the graft is positioned coaxially over theinner cannula26 and theconcentric cannula34 with the proximal end of thestent graft54 in longitudinal proximity relative to thedistal tip segment22 of thetip assembly18. During assembly, the distal end of thestent graft54 can be releasably coupled to theproximal end32 of thepositioner30 and the proximal end of thestent graft54 can be releasably coupled to thedistal tip segment22 of thetip assembly18, as described below.
The prosthesis52 may be releasably coupled to thedelivery device2 at theprosthesis retention region16 in a variety of ways.FIGS. 12-15 illustrate one non-limiting example of an attachment and release mechanism for the distal end of astent graft54. In this example, a prosthesis attachment mechanism releasably may couple thedistal end58 of thestent graft54 to theproximal end32 of thepositioner30. More particularly, the attachment mechanism may comprise threedistal trigger wires40 each having a proximal end42. However, other attachment mechanisms, including fewer or more distal trigger wires may also be used to releasably couple thedistal end58 of thestent graft54 to thepositioner30. Further, other attachment mechanisms, in addition to the one or moredistal trigger wires40, may also be used to couple thedistal end58 of thestent graft54 to thedelivery device2, such as diameter reducing ties, a retractable sheath, sutures and the like as will be recognized by one of skill in the art. U.S. application Ser. No. 13/970,861 filed on Aug. 20, 2013, describes one example of a releasable diameter reducing tie, which application is incorporated by reference herein in its entirety.
Thedistal trigger wires40 may extend longitudinally within a lumen ofpositioner30 proximally from thehandle assembly8 to thedistal end58 of the stent graft. More particularly, the distal ends of thedistal trigger wires40 may be coupled to one or more trigger wire release mechanisms that are disposed about and/or around at least a portion of themain handle10, as described further herein.
The proximal ends42 of thedistal trigger wires40 exit thepositioner30 at itsproximal end32 and are releasably coupled to thedistal end58 of thestent graft54. In one example, thedistal trigger wires40 may be directly or indirectly attached to thedistal end58 of thestent graft54. For example, thedistal trigger wires40 may engage suture loops (not shown) which are attached to thedistal end58 of thestent graft54. In this way, the trigger wires do not weave directly through thegraft material62. Alternatively, thedistal trigger wires40 may be woven directly through or removably attached to thegraft material62 or woven over or through one ormore stents60 at thedistal end58 of thestent graft54.
In the example shown inFIGS. 14-16, the threedistal trigger wires40 are woven directly through thegraft material62 at thedistal end58 of thestent graft54 and engagesuture loops78 attached to thepositioner30 at itsproximal end32. More particularly, thedistal trigger wires40 are woven directly through thegraft material62 at thedistal end58 of the stent graft at three spaced apart points around the periphery of the tubular graft body (for example, at radial positions approximately 120 degrees apart) such that when those points are retained by thetrigger wires40 against thepositioner30, the distal end of thestent graft54 generally forms a “cloverleaf” formation with each lobe of the “cloverleaf” being approximately the same size. Of course, other points of attachment may also be used to releasably couple thestent graft54 to thepositioner30 to form various configurations at thedistal end58 of thestent graft54. After eachdistal trigger wire40 penetrates thegraft material62, the wire travels through asuture loop78 attached to the positioner30 (for example by tying each suture loop through a hole in the wall of the positioner30) and then back through thegraft material62. Such a configuration usingsuture loops78 attached to thepositioner30 may allow higher deployment and loading forces and than fixation methods using suture loops attached to thestent graft54 and reduce the risk of structural failure of the positioner, for example, in applications requiring high forces for loading and/or deployingstent grafts54. This configuration may also prevent undesired rotation of thepositioner30 relative to thestent graft54 so that the the rotational position of thestent graft54 can be more accurately adjusted during deployment. In addition, this configuration may reduce the risk of embolization during a procedure in which thestent graft54 is implanted into a patient by avoiding potentially loose suture loops on thestent graft54 from being exposed to the blood flow.
Again,stent graft54 is used for exemplary purposes only in this particular description of proximal stent graft attachment, but any type of prosthesis can be releasably coupled to the inner cannula in this manner. Other suitable attachment methods or mechanisms may be used to removably attach one or moredistal trigger wires40 to the distal end of thestent graft54, thereby coupling the stent graft to thepositioner30 until the trigger wire(s) are released during deployment, as would be recognized by one of skill in the art. Moreover, the attachment and release mechanism described above may be used to releasably couple a prosthesis to various types of delivery devices, including but not limited to the split sheath deployment system with a divided tip described further herein.
In addition, thedelivery device2 may also include an attachment and release mechanism for the proximal end of thestent graft54 as described further herein. In one non-limiting example, the proximal attachment mechanism may releasably couple theproximal end56 of thestent graft54 to thedistal tip segment22 of thetip assembly18. More particularly, the proximal attachment mechanism may comprise one or moreproximal trigger wires44 each having aproximal end46. Other attachment mechanisms, in addition to the one or moreproximal trigger wires44 may also be used to couple theproximal end56 of thestent graft54 to thedelivery device2, such as diameter reducing ties, a retractable sheath, sutures and the like as will be recognized by one of skill in the art. U.S. application Ser. No. 13/970,861 filed on Aug. 20, 2013, which application is incorporated by reference herein in its entirety, describes one example of a releasable diameter reducing tie.
In the non-limiting example, theproximal trigger wires44 may extend longitudinally within a lumen ofpositioner30 proximally from thehandle assembly8 and further within a lumen of thestent graft54 to theproximal end56 of thestent graft54. More particularly, the distal ends of theproximal trigger wires44 may be coupled to one or more trigger wire release mechanisms that are disposed about and/or around at least a portion of themain handle10, as described further herein. The proximal ends46 of the one ormore trigger wires44 are releasably coupled to theproximal end56 of thestent graft54. In one example, theproximal trigger wires44 may be directly or indirectly attached to theproximal end56 of thestent graft54 to releasably couple theproximal end56 of the stent graft to thedistal tip segment22 of thetip assembly18. For example, theproximal trigger wires44 may engage a suture loop (not shown) which is attached to theproximal end56 of thestent graft54. In this way, thetrigger wires44 do not weave directly through thegraft material62. Alternatively, theproximal trigger wires44 may be woven directly through or removably attached to thegraft material62 or woven over or through one ormore stents60 at theproximal end56 of thegraft54. In the event that astent graft54 includes a bare anchoring stent (not shown) extending proximally from theproximal end56, the one or more trigger wires my weave over and/or through the proximal bare stent to releasably couple theproximal end56 of the stent graft to thedistal tip segment22 of thetip assembly18.
The proximal ends46 of the one or moreproximal trigger wires44 may be retained within thedistal tip segment22 of thetip assembly18, such as by friction fit, adhesives, or other suitable releasable attachment means so as to hold theproximal end56 of thestent graft54 in a radially inwardly contracted delivery configuration and allow for the trigger wires to be pulled distally and released from theinner cannula26 when deployment of the proximal end of thestent graft54 is necessary or desired. Other suitable attachment methods or mechanisms may be used to removably attach theproximal trigger wires44 to the proximal end of thestent graft54 as would be recognized by one of skill in the art.
When deployment is desired, distal retraction of theproximal trigger wires44 and the distal trigger wires40 (such as by manipulation of one or more trigger wire release mechanisms of the handle assembly8) allows the proximal ends of theproximal trigger wires44 and thedistal trigger wires40 to be released from the proximal and distal ends of thestent graft54, allowing the proximal and distal ends of thestent graft54 to at least partially deploy radially outwardly within a vessel. If other diameter reducing ties are being used to radially restrain the proximal and distal ends of thestent graft54, those ties may also be removed by manipulation of the trigger wire release mechanisms to allow the stent graft to move from a radially inwardly constrained delivery configuration to a radially outwardly expanded configuration and fully deploy fromdelivery device2 within the vessel.
The above description of the coupling of prosthesis52 to thedelivery device2 is for exemplary purposes, and shall not be considered limiting, as different prostheses may be releasably coupled to the delivery device in different ways, and the proximal and distal ends of a particular prosthesis may be coupled to the delivery device in different ways. In addition, several other non-limiting examples of attachment and release mechanisms for the distal and proximal ends of the prosthesis52 that can be operated and manipulated using thehandle assembly8 are described herein.
The releasable coupling of prosthesis52 to thedelivery device2 at theprosthesis retention region16 secures the prosthesis52 to thedelivery device2 to radially inwardly restrain the prosthesis52 in a manner that may subsequently facilitate insertion of the subassembly comprising theinner cannula26, thepositioner30, theconcentric cannula34, and the prosthesis52 into an outer sheath, such as the sheath64 described below. As will be apparent, the sheath64 is configured to radially restrain other regions of the prosthesis52 for delivery in a low-profile configuration to a target site within a patient's anatomy.
As shown inFIGS. 1-2, 8 and 11, the longitudinally slideable and retractable sheath64 may extend along the length of thedelivery device2 from thefront handle12 to thetip assembly18. The sheath64 may be disposed coaxially about and/or over at least a portion of theinner cannula26. The sheath64 is configured to cover and assist in retaining a prosthesis52, such as stent graft, in a radially inwardly compressed, low-profile configuration during delivery of the prosthesis to a target site within a patient's anatomy.
In one example, the sheath64 may be a “split sheath,” meaning that there is asplit76 at a point between the proximal and distal ends of the sheath64, resulting in aproximal sheath segment66 and a distal sheath segment72 that must both be removed to expose the prosthesis52. Theproximal sheath segment66 may be disposed coaxially over a proximal portion of theinner cannula26 and may be attached or otherwise secured at itsproximal end68 to theproximal tip segment20, for example at or about the point where the forward proximal taper of the proximal tip segment begins, such as by adhesives, bonding, welding or other suitable attachment mechanisms. In this way, theproximal sheath segment66 is indirectly attached to theinner cannula26 via theproximal tip segment20. As a result, pushing theinner cannula26 in a proximal direction simultaneously causes proximal longitudinal movement of the inner cannula as well as proximal movement of theproximal tip segment20 and theproximal sheath segment66. The distal sheath segment72 may be disposed coaxially over at least a portion of thepositioner30 over a distal portion of theinner cannula26. The distal sheath segment72 may be connected at its distal end within thehandle assembly8 to facilitate retraction of the distal sheath segment72 distally, as described further herein.
In one example, thesplit76 in the sheath may be generally aligned at thedistal end58 of the prosthesis52 such that thedistal end70 of theproximal sheath segment66 and theproximal end74 of the distal sheath segment72 are disposed over a portion of the prosthesis52 at thedistal end58 of the prosthesis. In another example, thesplit76 in the sheath may be generally aligned with a fenestration (not shown) in the prosthesis52, such asstent graft54. This may allow cannulation of a branch vessel through the fenestration before one or both of the sheath segments are removed.
Before use of thedelivery device2 and during a procedure when the delivery device is tracked to a desired location within a patient's body, the prosthesis52 at theproximal end4 of thedelivery device2 is fully covered by sheath64 and held in a radially inwardly contracted condition. To deploy the prosthesis52 in a vessel lumen, removal of theproximal sheath segment66 and the distal sheath segment72 may proceed in two separate actions or manipulations of thehandle assembly8.
In one example, a first action may be to push theproximal sheath segment66 of the sheath64 proximally so as to remove theproximal sheath segment66 from the prosthesis52 and expose theproximal end56 of the prosthesis and the reverse distal taper ofdistal tip segment22 of thetip assembly18 as shown inFIGS. 3, 4 and 9. Several non-limiting examples of usinghandle12 to facilitate proximal longitudinal movement of theinner cannula26, thereby simultaneously pushing theproximal tip segment20 and theproximal sheath segment66 proximally, are described further herein. During removal of theproximal sheath segment66 from the prosthesis52 over thedistal tip segment22, longitudinal movement of thedistal tip segment22 is prevented because the distal tip segment, being indirectly attached to thepositioner30 and thus thehandle10 via theconcentric cannula34, is held in place.
When thedelivery device2 is used to deliver a prosthesis52 to a vessel having a branch vessel extending from a main vessel where cannulation of the branch vessel is necessary or desired, theproximal sheath segment66 may be only partially removed from the prosthesis52 to expose a fenestration (not shown) in the prosthesis52 for cannulation of the branch vessel through the fenestration prior to full deployment of the prosthesis52, as shown inFIG. 3. This may provide a higher degree of control over the position of the prosthesis52 anddelivery device2 during the cannulation procedure. Once cannulation of the branch vessel is complete, theproximal sheath segment66 may be pushed further until it is fully removed from the prosthesis52 and the reverse distal taper ofdistal tip segment22 is exposed, as shown inFIGS. 4 and 9. Alternatively, theproximal sheath segment66 may be fully removed from the prosthesis52 prior to cannulation.
The second action may be to retract the distal sheath segment72 distally over thepositioner30 to remove it from the prosthesis52 and expose thedistal end58 of the prosthesis at theproximal end32 of thepositioner30, as shown inFIGS. 5, 10 and 12. Several non-limiting examples of usinghandle14 to facilitate retraction of the distal sheath segment72 so as to remove it from the prosthesis52, thereby fully exposing the prosthesis52 between its proximal and distal ends, are described further herein.
In one example, when theproximal sheath segment66 has been pushed proximally a sufficient distance to expose theproximal end56 of the prosthesis52 and before retracting the distal sheath segment72 distally to expose thedistal end58 of the prosthesis, the user may proceed with removal of at least theproximal trigger wires44 and any other diameter reducing ties that may be present at theproximal end56 of the prosthesis (such as by manipulation of one or more trigger wire release mechanisms of thehandle assembly8 to retract the proximal trigger wires44) to allow theproximal end56 of the prosthesis to at least partially deploy radially outwardly within a vessel. Alternatively, the user may proceed with removal of at least theproximal trigger wires44 and any other diameter reducing ties that may be present at theproximal end56 of the prosthesis after theproximal sheath segment66 has been pushed proximally a sufficient distance to expose theproximal end56 of the prosthesis52 and the distal sheath segment72 has been retracted distally to expose thedistal end58 of the prosthesis.
When the distal sheath segment72 has been sufficiently retracted to expose thedistal end58 of the prosthesis, the user may then retract thedistal trigger wires40 and/or any other diameter reducing ties that may be present at thedistal end58 of the prosthesis (such as by manipulation of one or more trigger wire release mechanisms of the handle assembly8) to allow thedistal end58 of the prosthesis to at least partially deploy radially outwardly within a vessel. At this point, the prosthesis52 may be fully deployed within the vessel, as shown inFIG. 6. In another example, thehandle assembly8 may be manipulated further to facilitate release of other components, for example a top cap (not shown) necessary to allow the prosthesis52 to fully deploy.
Once the prosthesis52 has been fully released from thedelivery device2, thedelivery device2 can be removed from the patient's body. In one example, thedelivery device2 may be removed with theproximal sheath segment66 and the segment72 in the configuration described above when the prosthesis52 is fully deployed, as shown inFIGS. 7 and 13. The reverse distal taper of thedistal tip segment22 may facilitate efficient and easy withdrawal of thedelivery device2 from the body with reduced risk of thetip assembly18, theproximal sheath segment66, or other portions of thedelivery device2 from snagging, catching or otherwise interfering with the deployed prosthesis52. Thedelivery device2 can then be withdrawn distally, through the lumen of the prosthesis and retracted further until the device has been safely removed from the patient's body.
Throughout this specification, unless the context requires otherwise, the words “comprise” and “include” and variations such as “comprising” and “including” will be understood to imply the inclusion of an item or group of items, but not the exclusion of any other item or group items. While various embodiments have been described, it will be apparent to those of ordinary skill in the art that many more examples and implementations are possible within the scope of the present disclosure. Furthermore, although various indications have been given as to the scope of this present disclosure, the present disclosure is not limited to any one of these but may reside in two or more of these combined together. Accordingly, the present disclosure is not to be restricted except in light of the attached claims and their equivalents.