Abstract:
A stent graft introducer actuation assembly ( 1 ) having a fixed handle ( 3 ) and at least one sliding handle ( 5, 7 ), the sliding handle or handles telescoping within the fixed handle, and a winch arrangement ( 9 ) to retract the sliding handle into the fixed handle. There may be provided arrangements to give a mechanical advantage to the winch arrangement.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS  
       [0001]     This application is related to and claims priority from U.S. Provisional Patent Application No. 60/795,634 filed Apr. 26, 2006 entitled “Rotary Handle for Controlled Sequential Deployment” the contents of which are incorporated in their entirety herein and for all purposes. This application is related to and claims priority from U.S. Provisional Patent Application Ser. No. 60/795,617 filed Apr. 27, 2006 entitled “Controlled Sequential Deployment” the contents of which are incorporated in their entirety herein and for all purposes. 
     
    
     INCORPORATION BY REFERENCE  
       [0002]     The following co-pending patent applications are referred to in the following description:  
         [0003]     PCT Patent Publication No. WO 98/53761 entitled “A Prosthesis And A Method And Means Of Deploying A Prosthesis” discloses an introducer for a prosthesis which retains the prosthesis so that each end can be moved independently. These features and other features disclosed in PCT Patent Publication No. WO 98/53761 could be used with the present invention and the disclosure of PCT Patent Publication No. WO 98/53761 is herewith incorporated in its entirety into this specification” 
         [0004]     U.S. Provisional Patent Application Ser. No. 60/392,682, filed Jun. 28, 2002, U.S. patent application Ser. No. 10/447,406, filed May 29, 2003, and Published on Dec. 18, 2003, as U.S. Patent Application Publication No. US-2003-0233140-A1 entitled “Trigger Wire System”, and PCT Patent Publication No. WO 03/101518 entitled “Trigger Wire System For A Prosthesis Deployment Device” disclose release wire systems for the release of stent grafts retained on introducer devices. This feature and other features disclosed in U.S. Provisional Patent Application Ser. No. 60/392,682, U.S. patent application Ser. No. 10/447,406, and U.S. Patent Application Publication No. US-2003-0233140-A1, and PCT Patent Publication No. WO 03/101518 could be used with the present invention and the disclosure of U.S. Provisional Patent Application Ser. No. 60/392,682, U.S. patent application Ser. No. 10/447,406, and U.S. Patent Application Publication No. US-2003-0233140-A1, and PCT Patent Publication No. WO 03/101518 is herewith incorporated in its entirety into this specification  
       TECHNICAL FIELD  
       [0005]     This invention relates to a controlled sequential deployment device for endovascular stent grafts and more particularly to a method of actuation of such a device.  
       BACKGROUND OF THE INVENTION  
       [0006]     In our earlier patent application, PCT Patent Publication No. WO 98/53761 entitled “A prosthesis and a method deploying a prosthesis” there is disclosed an introducer for a stent graft which retains the stent graft so that each end can be moved independently during the process of endovascular deployment of the stent graft. This device requires that a number of actions be taken in a particular consecutive order to place a stent graft in the required position in the vasculature and then release one end of the stent graft and then another end and if required, between the release of each of the ends, the placement of a branch stent graft from a side arm of the stent graft. These features and other features disclosed in PCT Patent Publication No. WO 98/53761 are incorporated herewith in their entirety into this specification.  
         [0007]     It is desirable that the set of sequential actions necessary to release the stent graft at the desired position in the vasculature be undertaken in the required order and that there be less chance for operator error during such a deployment.  
         [0008]     In our patent application US Provisional Patent Application Serial No (PA-5858-PRV), a system is disclosed for the controlled sequential deployment of a stent graft into the vasculature of a patient. The device includes at least one telescoping slide which assists in drawing back the sheath from a stent graft and release stent graft retention wires.  
         [0009]     It has been found, however, that a stent graft which includes self expanding stents engaging against the inner surface of the sheath, trigger wires retaining the graft onto the pusher as well as the general friction of interacting components can provide significant load. It is the intention of this invention to provide a system to assist with the withdrawing of at least one sliding portion into the handle of a controlled sequential release device.  
       SUMMARY OF THE INVENTION  
       [0010]     In one form therefore, the invention is said to reside in a stent graft introducer actuation assembly, the introducer comprising a pusher, a stent graft releasably retained onto the pusher, a sheath coaxially around the pusher and enclosing the stent graft and a sheath hub to which the sheath is mounted, the actuation assembly comprising a fixed handle and a sliding handle, the sliding handle telescoping within the fixed handle, the sheath hub being retained to the sliding handle and the pusher extending from the fixed handle through the sliding handle, and a winch arrangement to retract the sliding handle into the fixed handle to thereby withdraw the sheath from the stent graft.  
         [0011]     Preferably the winch arrangement comprises a ratchet arrangement to allow rotation of the winch arrangement only in a retraction direction.  
         [0012]     In a preferred embodiment the winch arrangement comprises a winch drum, a rotation handle for the winch drum and a cable extending from the winch drum to the sliding handle.  
         [0013]     The winch drum can be mounted on an axis transverse to the longitudinal extent of the actuation assembly or alternatively the winch drum can be mounted on an axis parallel to the longitudinal extent of the actuation assembly.  
         [0014]     Hence, in one embodiment the winch arrangement comprises a winch drum, a rotation handle for the winch drum and a cable extending from the winch drum to the sliding handle, the winch drum and rotation handle rotating on a longitudinal axis parallel to the longitudinal extent of the actuation assembly.  
         [0015]     The cable can comprise a band or ribbon of relatively inextensible material or a wire, such as a twisted or braided wire cable.  
         [0016]     Preferably the actuation assembly comprises the fixed handle, a release portion and the sliding handle, the release portion telescoping within the fixed handle and the sliding handle telescoping within the release portion.  
         [0017]     The actuation assembly can include a first removable stop pin to prevent movement of the sliding handle with respect to the release portion and a second removable stop pin to prevent movement of the release portion with respect to the fixed handle. It may also include a third removable stop pin acting between the fixed handle and the release portion to restrict the distance of retraction of the release portion into the fixed handle until the third stop pin is removed.  
         [0018]     The fixed handle can include a first grip and the sliding handle can include a second grip.  
         [0019]     In an alternative form the invention comprises a stent graft introducer actuation assembly, the introducer comprising a pusher, a stent graft releasably retained onto the pusher, a sheath coaxially around the pusher and enclosing the stent graft and a sheath hub to which the sheath is mounted, the actuation assembly comprising a fixed handle, a release portion and a sliding handle, the release portion telescoping within the fixed handle and the sliding handle telescoping within the release portion, the sheath hub being retained to the sliding handle and the pusher extending from the fixed handle through the release portion and sliding handle, a winch arrangement to retract the sliding handle and release portion into the fixed handle to thereby withdraw the sheath from the stent graft, a first removable stop pin to prevent movement of the sliding handle with respect to the release portion and a second removable stop pin to prevent movement of the release portion with respect to the fixed handle, a third removable stop pin acting between the fixed handle and the release portion to restrict the distance of retraction of the release portion into the fixed handle until the third removable stop pin is removed, the winch arrangement comprising a winch drum, rotation handle for the winch drum and a cable extending from the winch drum to and affixed to the sliding handle, the winch drum and rotation handle rotating on a longitudinal axis parallel to the longitudinal extent of the actuation assembly and the cable comprising a band or ribbon of relatively inextensible material.  
         [0020]     In an alternative form the invention comprises a stent graft introducer actuation assembly comprising a fixed handle and a sliding handle, the sliding handle telescoping within the fixed handle, the sheath hub being retained to the sliding handle and the pusher extending from the fixed handle through the sliding handle, and a winch arrangement to retract the sliding handle into the fixed handle to thereby withdraw the sheath from the stent graft.  
         [0021]     In an alternative form the invention comprises a stent graft introducer actuation assembly comprising a fixed handle, a release portion and a sliding handle, the release portion telescoping within the fixed handle and the sliding handle telescoping within the release portion, a winch arrangement to retract the sliding handle and release portion into the fixed handle, a first removable stop pin to prevent movement of the sliding handle with respect to the release portion and a second removable stop pin to prevent movement of the release portion with respect to the fixed handle, a third removable stop pin acting between the fixed handle and the release portion to restrict the distance of retraction of the release portion into the fixed handle until the third removable stop pin is removed, the winch arrangement comprising a winch drum, a rotation handle for the winch drum and a cable extending from the winch drum to and affixed to the sliding handle, the winch drum and rotation handle rotating on a longitudinal axis parallel to the longitudinal extent of the actuation assembly and the cable comprising a band or ribbon of relatively inextensible material.  
         [0022]     Throughout this specification the term distal with respect to a portion of the aorta, a deployment device or a prosthesis is the end of the aorta, deployment device or prosthesis further away in the direction of blood flow away from the heart and the term proximal means the portion of the aorta, deployment device or end of the prosthesis nearer to the heart. When applied to other vessels similar terms such as caudal and cranial should be understood.  
         [0023]     This then generally describes the invention but to assist with understanding reference will now be made to the accompanying drawings. 
     
    
     BRIEF DESCRIPTION OF THE DRAWING  
       [0024]     In the drawings;  
         [0025]      FIG. 1  shows a side view of first embodiment of a stent graft retraction device according to a first embodiment of the present invention;  
         [0026]      FIG. 2  shows a longitudinal cross-sectional view of the device shown in  FIG. 1 ;  
         [0027]      FIGS. 3A, 3B  and  3 C show a side view and cross-sectional view of a first slide component of the stent graft retraction device of  FIG. 1  and a detailed view of the connection of the winch cable to the first slide;  
         [0028]      FIGS. 4A and 4B  show a top view and cross-sectional view of the second slide component of the stent graft retraction device of  FIG. 1 ;  
         [0029]      FIGS. 5A and 5B  show a top view and a cross-sectional view of a rotary handle portion of the stent graft stent graft retraction device of  FIG. 1 ;  
         [0030]      FIGS. 6A and 6B  show a top view and a cross-sectional view of the fixed handle portion of the stent graft retraction device of  FIG. 1 ;  
         [0031]      FIGS. 7A  to  7 E show the various stages of operation of the stent graft introducer actuation assembly of  FIG. 1  and  FIG. 2 ;  
         [0032]      FIG. 8  shows a perspective view of a stent graft introducer and actuation handle assembly according to the embodiment of the invention shown in  FIG. 1 ;  
         [0033]      FIGS. 9A  to  9 C show the various stages of operation of an alternative embodiment of a stent graft introducer actuation assembly according to the present invention;  
         [0034]      FIG. 10  show the an alternative embodiment of a stent graft introducer actuation assembly according to the present invention; and  
         [0035]      FIGS. 11 and 11 A show a still further alternative embodiment of a stent graft introducer actuation assembly according to the present invention and its method of operation.  
         [0036]      FIG. 12  shows a shows a longitudinal cross-sectional view of the embodiment of the actuation assembly shown in FIGS.  1  to  6  with a stent graft introducer carried in it.  
     
    
     DETAILED DESCRIPTION  
       [0037]     Now looking more closely at the drawings and in particular FIGS.  1  to  6  it will be seen that the stent graft introducer actuation assembly  1  comprises generally a fixed handle  3 , a first slide or sliding handle  5  and a second slide or release portion  7 . On the fixed handle  3  is a rotary handle  9 .  
         [0038]     The fixed handle  3  as shown in details in  FIGS. 6A and 6B  comprises an elongate tubular body  11  with a closed distal end  13 . Hand grips  15  are provided on the outside of the fixed handle  3 .  
         [0039]     A toothed ring  17  is moulded into the outer surface of the fixed handle  3 , the use of which will be discussed later. An annular groove  19  in the distal closed end  13  acts as a support for a winch drum which is integral with the rotary handle  9  as will be discussed later. An aperture  21  is provided for a removable second stop pin and aperture  23  is for a third removable stop pin as will be discussed later.  
         [0040]     First slide  5  as shown on detail in  FIGS. 3A and 3B  includes a socket  31  for the hub of a sheath manipulator of a stent graft as will be discussed in relation to  FIG. 8 . The first slide  5  includes an elongate tubular body  33  with a groove  35  along it into which is engaged a pin (not shown) which prevents relative rotation of the first slide  5  and the second slide  7 . Apertures  37  provides an original locking arrangement to prevent movement of the first slide  5  in respect of the second slide  7  until it is required. The selection of which aperture  37  is used depends upon the length of a stent graft deployed using the device of the present invention.  
         [0041]     Connection of the cable  51  to the first slide is shown in the detail drawing  FIG. 3C . A groove  34  is formed in the wall of the tubular body  33  of the first slide  5  and the groove terminates in a through aperture  32 . The cable  51  has a blob of solder or other protrusion  52  formed at its proximal end and the blob  52  is received in the through aperture  32  and the cable  51  lies in the groove  34 .  
         [0042]     The second slide  7  as shown on detail in  FIGS. 4A and 4B  includes an elongate tubular body  41  which slides inside the fixed handle  3 . The body  41  has a closed distal end  43 . The first slide  5  slides within the second slide  7 .  
         [0043]     The rotary handle  9  as shown on detail in  FIGS. 5A and 5B  comprises a tubular body  45  which fits over the distal end of the fixed handle  3 . Within the tubular body  45  of the rotary handle  9  is a integral winch drum  47  which is formed on the back wall  49  of the rotary handle  9 . The winch drum has a bearing protrusion  51  which when mounted to the fixed handle  3  engages in and is supported by the annular groove  19  in the end  13  of the fixed handle  3  as shown in  FIG. 6B . A ratchet assembly  46  mounted into the rotary handle  9  has a detent pin  48  which in use engages into the toothed ring  17  (see  FIG. 6A ) moulded into the outer surface of the fixed handle  3  such that the rotary handle can only be rotated in one direction. The detent pin  48  also assists in holding the rotary handle  9  engaged onto the fixed handle  3 .  
         [0044]     As can be particularly seen in the cross sectional view,  FIG. 2 , a cable or inextensible band  51  is mounted at one end to the outer surface of the tubular body  33  of the first slide  5  at position  53  as discussed above in relation to  FIG. 3C . The cable extends through an aperture  55  in the rear surface  43  of the second slide  7 . The cable then passes through an aperture  57  in the distal end  13  of the fixed handle  3  before extending past the winch drum  47  and then extending through aperture  58  in the rotary handle and being fastened at  59  to the rotary handle  9 .  
         [0045]     The operation of the winch actuated controlled sequential deployment actuator of one embodiment of the present invention is shown in  FIGS. 7A  to  7 E.  
         [0046]      FIG. 7A  shows the same as  FIG. 2  except that the winch drum  47  on the rotary handle  9  is shown not in cross-section to more clearly show how it is used. In these views the stent graft deployment device with which the actuation assembly is used is not shown.  
         [0047]     As shown in  FIG. 7B  the rotary handle  9  has been turned through about one turn and the cable  51  has been drawn around the winch drum  47  because it is fixed at  59  and passes through the aperture  57  in the fixed handle  3 . A catch arrangement between the fixed handle  3  and the second slide  7  (not shown) prevents movement of these two items until the first slide  5  has been fully retracted and hence at this stage only the first slide  5  is retracted.  
         [0048]     With continued rotation of the rotary handle  9  with respect to the fixed handle  3  as shown in  FIG. 7C , more cable  51  has wound on to the drum  47  and the first slide  5  has fully retracted into the second slide  7 . At this stage the catch arrangement (not shown) is released so that the second slide can move in respect to the fixed handle  3 .  
         [0049]     Also as shown in  FIGS. 7D and 7E , continued rotation of the rotary handle  9  with respect to the fixed handle  3  winds more cable  51  onto the drum  47  and the first and the second slides  5  and  7  respectively move into the fixed handle  3 .  
         [0050]     It will be seen therefore that by holding the fixed handle  3  stationary and rotating the rotary handle  9  the cable  51  is caused to wind onto the winch drum  47  and this causes the first and second slides to be withdrawn into the fixed handle  3 .  
         [0051]      FIG. 8  shows the assembly of a controlled sequential actuation device according to the embodiment shown in FIGS.  1  to  6  with a stent graft deployment device mounted into it. The actuation device includes a fixed handle  103  with a first slide  105 , a second slide  107  and a rotary handle  109 . A first removable stop pin  60  prevents relative movement of the first slide  105  in respect to the second slide  107  until it is removed. A second removable stop pin  62  prevents relative movement of the second slide  107  into the fixed handle  103 . A third removable stop pin  64  prevents complete retraction of the second slide  107  into the fixed handle  103  until it is removed.  
         [0052]     The stent graft introducer mounted onto the actuation assembly includes a hub assembly  70 , a sheath  72  mounted onto the hub and a nose cone dilator  74 . The stent graft to be introduced is retained in the region  76  underneath the sheath  72 . A main pusher catheter (not shown) of the stent graft introducer extends from the fixed handle  103  to distal of the stent graft in the region  76  just distal of the nose cone dilator  74 . The hub  70  of the sheath manipulator is mounted into the socket  31  by means of a bayonet clip arrangement  78 .  
         [0053]     Rotation of the rotary handle  109  in respect of the fixed handle  103  causes the sheath  72  to be retracted distally from the nose cone dilator to expose and release the stent graft  76 .  
         [0054]      FIGS. 9A  to  9 C show in cross sectional view an alternative embodiment of actuation assembly for stent graft introducer. In these views the stent graft deployment device with which the actuation assembly is used is not shown.  
         [0055]     In this embodiment the actuation assembly  80  includes a fixed handle  82 , a first slide  84  and a second slide  86 . In the fixed handle  82  there is an interior recesses  88  into which is mounted a winch drum  90  actuated by handle  92 . A cable  94  is mounted to the winch drum  90  and extends forward to be mounted at  96  in the first slide  84 .  
         [0056]     In a similar manner to that explained in relation to  FIG. 7 , rotation of the winch handle causes the cable  94  to be wound onto the winch drum  90  so that the first slide  84  is retracted into the second slide  86  and then as shown in  FIG. 9B  the first and second slides are retracted into the fixed handle  82  until both slides are fully retracted as shown in  FIG. 9C .  
         [0057]      FIG. 10  shows an alternative embodiment of a stent graft introducer actuation assembly according to the present invention. In this embodiment the same reference numerals as used in relation to FIGS.  1  to  6  are used for corresponding items.  
         [0058]     The stent graft introducer actuation assembly  100  of this embodiment comprises generally a fixed handle  3 , a first slide  5  and a second slide  7 . On the fixed handle  3  is a rotary handle  9 . To give additional mechanical advantage to the winch arrangement  102  on the rotary handle  9  the cable  104  extends from its fixing point  106  on the rotary handle to a boss or pulley on the first slide  5  and then back to a fixing  110  on the end piece  13  of the fixed handle  3 . Rotation of the rotary handle  9  will give an increased mechanical advantage to retraction of the slides.  
         [0059]      FIGS. 11 and 11 A show a still further alternative embodiment of a stent graft introducer actuation assembly according to the present invention and its method of operation. In this embodiment the same reference numerals as used in relation to FIGS.  1  to  6  are used for corresponding items.  
         [0060]     The stent graft introducer actuation assembly  120  of this embodiment comprises generally a fixed handle  3 , a first slide  5  and a second slide  7 . On the fixed handle  3  is a rotary handle  9 . To give additional mechanical advantage to the winch arrangement  102  on the rotary handle  9  the winch drum  122  is tapered to give a reduced diameter  126  where the cable  124  first winds onto the winch drum. This means that additional turns are necessary to retract the slides early on in retraction of the first slide into the second slide which will give an increased mechanical advantage to the retraction where it is needed most due to greater friction.  
         [0061]      FIG. 12  shows a longitudinal cross-sectional view of the embodiment of the actuation assembly shown in FIGS.  1  to  6  with a stent graft introducer carried in it.  
         [0062]     In this embodiment, the actuation assembly  1  comprises a handle portion  3 , a first slide  5  and a second slide  7 . The first slide  5  has a hub retention socket  31  and into this is received the hub  130  of a stent graft introduction assembly  132 . A sheath  134  is mounted to the hub  130  and extends forward to a nose cone dilator  136 . Just distal of the nose cone dilator and within the sleeve  134  a stent graft  138  is retained. A trigger wire  140  or a set of trigger wires engages with the exposed stent  142  at the proximal end of the stent graft  138  and retains the proximal end of the stent graft to the stent graft introduction assembly  132 . The trigger wire or wires extend distally through a lumen of the pusher catheter  144  to a trigger wire clamp  146  at the distal end of the second slide  7 .  
         [0063]     A method of retention of the proximal end of a stent graft onto a introducer is disclosed in PCT Publication WO03/101518 entitled “Trigger Wire System for a Prosthesis Deployment Device”. This feature and other features disclosed in PCT Publication WO03/101518 could be used with the present invention and the disclosure of PCT Publication WO03/101518 is herewith incorporated in its entirety into this specification.  
         [0064]     The hub  130  is retained in the hub socket  31  on the first slide  5  by means of a bayonet lock arrangement as can be see particularly in  FIG. 8 .  
         [0065]     The pusher catheter  144  extends back through the hub  130  to a mounting position  150  within the handle portion  3 . The first slide  5  slides within the second slide  7  and a first removable stop pin  152  prevents relative movement of the first slide within the second slide until the locking pin  152  has been removed. The second slide  7  includes the trigger wire clamp  146  at the distal end thereof and a second removable stop pin  154 .  
         [0066]     A third removable stop pin  156  provides an intermediate stop positions during withdrawal of the sheath  134  from the stent graft  138 .  
         [0067]     In a first stage of operation of the stent graft introducer actuation assembly according to this embodiment the first removable stop pin  152  is withdrawn so that the first slide  5  can slide within the second slide  7 . As the hub  130  is connected to the first slide  5 , the hub and therefore the sheath  134  is withdrawn from the nose cone dilator  136  so that the stent graft  138  is partially exposed. At this stage, the exposed stent  142  at the proximal end of the stent graft  138  is still retained just distal of the nose cone dilator  136 .  
         [0068]     In the next stage the first slide  5  continues to slide back inside the second slide  7  until the distal end of the first slide  5  is fully retracted into the second slide  7 . The second removable stop pin  154  can then be removed which enables the second slide  7  and first slide  5  to be able to slide into the handle portion  3 .  
         [0069]     At this stage, more of the stent graft  138  is exposed but the exposed stent  142  at the proximal end of the stent graft  138  is still retained just distal of the nose cone dilator  136 .  
         [0070]     Continued movement of the first slide  5  along with the second slide  7  within the handle portion  3  can occur until the distal end  157  of the second slide  7  engages third removable stop pin  156 . During this stage, because the distal end of the trigger wire or wires  140  are clamped by the trigger wire clamp  146  on the distal end of the second slide  7 , movement of the second slide  7  pulls the trigger wire  140  from its retention arrangement at the proximal end of the stent graft  138  so the proximal end of the stent graft is freed. At the same time, the sheath  134  has been withdrawn so that the distal end of the main body of the stent graft  138  is still retained within the sheath.  
         [0071]     At this stage, a side arm can be deployed such as in relation to deployment about the aortic bifurcation by access from the contra-lateral iliac artery to engage an extension arm into the side arm. Our earlier PCT Patent Publication No. WO 98/53761 discussed above showed how such a deployment can be done.  
         [0072]     The third removable stop pin  156  can then be removed and the first and second slides continued in their movement back into the handle portion  3 . Completion of the movement of the first and second slides  5  and  7  into the handle portion  3  ensures that the sheath  134  is completely withdrawn from the stent graft  138  and the stent graft  138  is released.  
         [0073]     The hub  130  can then be released from the hub socket  31  on the first slide  5  so that the pusher  144  and nose cone dilator  136  can be withdrawn through the sleeve  134  along with the actuation assembly, leaving the hub and sheath in place. Subsequent deployment operations can be made through the sheath  134  and hub  130  as required.  
         [0074]     It will be seen by this invention an arrangement is provided by which considerable mechanical advantage can be provided to retract the sheath of a stent graft introducer to assist with overcoming friction between the stent graft and a enclosing sheath.