Patent Publication Number: US-9849012-B2

Title: Port retention mechanism for deployment handle of a medical device deployment system

Description:
BACKGROUND 
     Field 
     The present disclosure relates to medical device deployment systems. More particularly, the present disclosure relates to a handle for a medical device deployment system. 
     Discussion of the Related Art 
     There is a need for advanced devices, tools, systems and methods used for the endoluminal treatment of aortic diseases. In particular, there remains a need for deployment systems that can accommodate increasingly complex modes of deployment of a device, such as steering, reconstraining, multiple stage deployment, multiple device deployment, while promoting ease of use to the clinician. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The accompanying drawings are included to provide a further understanding of the present disclosure and are incorporated in and constitute a part of this specification, illustrate embodiments of the present disclosure, and together with the description serve to explain the principles of the present disclosure. 
         FIG. 1  is an exploded perspective view of an introducer assembly in accordance with the present disclosure; 
         FIGS. 2-8  illustrate various states of a handle of the introducer assembly of  FIG. 1 ; 
         FIGS. 9A and 9B  are top and front elevational views, respectively, of a handle of the introducer assembly in a first state. 
         FIGS. 9C and 9D  are top and front elevational views, respectively, of a handle of the introducer assembly in a second state. 
         FIG. 10  is a perspective view of a front portion of the introducer assembly; 
         FIG. 11  is a cross-sectional view of a front portion of the introducer assembly; 
         FIG. 12  is a perspective view of a rear portion of the introducer assembly; 
         FIG. 13  is a cross sectional view of a rear portion of the introducer assembly; 
         FIG. 14  illustrates perspective views of a handle and sheath of an introducer assembly decoupled from each other; 
         FIG. 15  is a perspective view of a portion of a catheter assembly illustrating a first catheter seated and retained by a cinching mechanism on a second catheter; and 
         FIG. 16  is a perspective view of the catheter assembly of  FIG. 15  with the second catheter unseated from the first catheter. 
     
    
    
     DETAILED DESCRIPTION 
     Introducer assemblies for endoluminal delivery of vascular implants in accordance with various embodiments are disclosed for allowing actuation or deployment of a vascular implant, while forcing a particular order of operation of the handle by a clinician. 
     In various embodiments, an introducer assembly includes a first actuating mechanism for actuating a constraining sheath between a first state releasably constraining a vascular implant and a second state allowing deployment of the vascular implant; a second actuating mechanism for actuating a blocking mechanism between a blocked state for blocking one or more other knobs and/or other functions of the handle and an unblocked state for allowing operation of the one or more other knobs and/or other functions of the handle; and an operating knob operatively coupled to both of the first and second actuating mechanisms for concurrent operation of both of the first and second actuating mechanisms in response to actuation of the operating knob. An example of such an introducer assembly is generally indicated at  100  in  FIG. 1 . The introducer assembly  100  includes a sheath  200  and a handle  300 . The introducer assembly  100  includes a constraint (not shown) for releasably constraining a vascular implant toward a distal end  210  of the sheath  200 . The constraint has a first state releasably constraining an expandable implant toward a delivery configuration suitable for endoluminal delivery, and a second state released to allow expansion of the implant from the delivery configuration toward a deployed configuration. The handle includes an actuating member operatively coupled to the constraint for actuating the constraint between the first state and the second state. 
     In various embodiments, the constraint can include a film sleeve that extends around the implant. In the first state, opposite portions or edges of the film sleeve can be releasably held or sewn together by an elongated member, such as a wire or fiber, to maintain the implant in the delivery configuration. In such embodiments, the sleeve can be opened, or otherwise disrupted, by displacing, unstitching or otherwise disengaging the elongated member from the film sleeve to allow expansion of the implant. Further details of such constraining sleeves can be found, for example, U.S. Pat. No. 6,352,561 issued to Leopold, et al., and U.S. Pat. No. 6,551,350 issued to Thornton, et al., the content of which is incorporated herein by reference in its entirety. In such embodiments, the actuating member can be coupled to the elongated member to release or open the film sleeve from the first state to the second state. 
     In other embodiments, the constraint can include an axially displaceable tube, wherein such a tube can be formed from a wrapped film tube or an extruded polymer. Indeed, in various embodiments, the sheath itself could be such a constraint, wherein the sheath in the first state extends over the implant to retain the implant toward the delivery configuration. The sheath can be displaced toward the second state to allow expansion of the implant from the delivery configuration. In such embodiments, the actuating member can be coupled to the sheath so that the sheath is displaced with the actuating member between the first state and second state. 
     Thus, the actuating member can be configured for deploying an implant from either type of constraint described above, or other similarly actuated constraint mechanisms known in the art. The latter type of integrated sheath and constraint are described below in connection with the illustrated embodiments. 
     Referring to  FIGS. 9A-9D , the handle  300  includes an actuating member  310  coupled to the sheath  200  for actuating the sheath  200  between the first state and second state in response to linear displacement of the actuating member  310  between a first position and a second position, respectively. The handle  300  includes a first actuating mechanism  320  for displacing the actuating member  310  between the first position and the second position. 
     The handle  300  includes a main knob  330  for operating the first actuating mechanism  320 . Described further below, the handle  300  can include one or more additional knobs to operate one or more additional separate handle functions. The handle  300  includes a cover  350  operable for movement between a covered state covering the one or more additional knobs  340 ,  342 ,  344  as shown in  FIGS. 9A and 9B , and an uncovered state allowing access to the one or more additional knobs  340 ,  342 ,  344  as shown in  FIGS. 9C and 9D . The handle  300  includes a second actuating mechanism  360  for displacing the cover  350  between the covered state and the uncovered state. The main knob  330  is operatively coupled to both of the first actuating mechanism  320  and the second actuating mechanism  360  to cause displacement of both the actuating member  310  between the first state and the second state and the cover  350  between the covered state and the uncovered state, respectively, in response to corresponding operation of the main knob  330 . 
     In various embodiments, an actuating knob of the handle can be configured for rotation about an axis, and an actuating member for actuating one or more functions of the handle can be configured for displacement along and/or about the axis between operating states in response to corresponding rotation of the actuating knob. For example, as shown in  FIGS. 9A-9D , the main knob  330  is rotatable about a rotational axis  332 . The actuating member  310  is movable linearly along the axis  332  between the first state and second state. Referring to  FIGS. 10 and 11 , the first actuating mechanism  320  includes a first helical guide  322  movable with the main knob  330  about the axis  332 . The first actuating mechanism  320  includes a first follower  324  on the actuating member  310  engaged with the first helical guide  322  to cause linear movement of the actuating member  310  between the first state and second state in response to corresponding rotation of the main knob  330 . The main knob  330  includes a receiving tube  334  receiving at least a portion of the actuating member  310  therethrough as the actuating member  310  moves between the first state and second state. In a number of embodiments, the first helical guide  322  is a first helical slot  326  formed along an inner surface  336  of the receiving tube  334  and the first follower  324  includes an outwardly extending first pin  338  engaged with the helical slot  326 . 
     Referring to  FIG. 12 , the second actuating mechanism  360  includes a second helical guide  362  that translates rotation of the main knob  330  to axial displacement of the cover  350 . In one embodiment, the second helical guide  362  comprises a second helical slot  368  formed along an outer surface  366  of a spindle  364 , the spindle  364  being aligned with the axis  332  of the main knob  330 . The second actuating mechanism  360  also includes a longitudinal slot  366  formed along the main knob  330 . In various embodiments, the slot  366  is parallel with the axis  332  of the main knob  330 . The second actuating mechanism  360  includes a second pin  363  extending from the cover  350  and slidably engaged with the longitudinal slot  366 . As best shown in  FIG. 13 , the second actuating mechanism  360  includes a third pin  352  extending from the cover  350  and engaging the second helical slot  368  to cause displacement of the cover  350  between the covered state and the uncovered state in response to corresponding rotation of the main knob  330 . 
     The actuating mechanisms of the handle can be configured so that functions, such as displacements of the actuating member and cover, are delayed or accelerated relative to each other during operation of the main knob. For example, the first helical guide can include a flat or reduced or increased pitch to cause a delay, decrease or increase, respectively, in the displacement of the actuating mechanism relative to the cover in response to operation of the main knob. 
     In various embodiments, the handle can include a ratchet mechanism that allows actuation of an actuating knob in a first direction and prevents rotation of the actuating knob in an opposite second direction. For example, the handle can include a ratchet mechanism having a gear rack on the main knob and a fixed pawl that engages the gear rack to allow rotation of the main knob in a first direction as the pawl slips along teeth of the gear rack and that limits rotation of the main knob in an opposite second direction as the pawl catches a tooth on the gear rack. The pawl can be a spring-loaded machined component or alternatively, the pawl can be formed from spring leaf metal. The pawl can be configured to generate audible noise and/or at least provide tactile feedback as the pawl slips along the teeth of the gear rack. Optionally, one or more of the teeth of the gear rack can be sized and/or shaped differently from the other teeth of the gear rack to cause a distinct change in sound, e.g. pitch, or tactile feedback, e.g. clicks, resistance, that indicates to a clinician when a certain step in the deployment is achieved. 
     In use, rotation of the main knob  330  about the axis  332  simultaneously operates the first actuating mechanism  320  to cause displacement of the actuating member  310  in a first direction, as indicated at arrow “a” in  FIG. 2 , and the second actuating mechanism  360  to cause displacement of the cover  350  in a second direction, as indicated at arrow “b” in  FIG. 2 . Displacement of the actuating member  310  in the first direction “a” causes corresponding displacement of the sheath  200  to allow expansion of the expandable implant  400  outwardly from the delivery configuration. The expandable vascular implant can be a self-expanding stent graft or, alternatively, a balloon-expanded implant. Displacement of the cover  350  in the second direction “b” can reveal one or more additional knobs each for operating one or more other handle functions. 
     For example, as illustrated in  FIG. 3 , a second knob  340  is revealed after displacement of the cover  350  for operating a constraining mechanism for selectively constraining at least a portion of the implant to allow positioning of the device prior to committing to a full deployment of the implant at the treatment site. A detailed description of constraining mechanisms, construction and methods of use of such constraining mechanisms are provided in co-pending application U.S. Patent Application Publication US 2010/0049293 A1 (Zukowski et al.), the content of which is incorporated herein by reference in its entirety. 
     In various embodiments, the handle can be configured so that the cover can be displaced in steps to reveal additional knobs each for operating one or more other handle functions. 
     Continued rotation of the main knob  330 , for example, as illustrated in  FIG. 4 , causes further displacement of the cover  350  in the second direction “b” to reveal a third knob  342 , as shown in  FIG. 5 . The third knob  342  can be configured to actuate one or more other handle functions, such as displacing fibers, wires, levers, gears or any combination thereof of a steering mechanism (not shown) for selectively bending or otherwise steering at least a portion of the implant  400  during deployment. 
     Continued rotation of the main knob  330 , for example, as illustrated in  FIG. 6 , causes further displacement of the cover  350  in the second direction “b” to reveal a fourth knob  344 , as shown in  FIGS. 7-8 . The fourth knob  344  can be configured to actuate one or more other handle functions, such as displacing fibers, wires, levers, gears or any combination thereof of a release mechanism. In one embodiment, a release mechanism can include a lock wire frictionally engaged with the implant to maintain a releasable coupling between the implant and the handle. The lock wire can be operatively coupled to the fourth knob to be displaced relative to and disengaged from the implant in response to actuation of the fourth knob. For example, the lock wire can be wound about a spindle portion of the fourth knob during rotation of the fourth knob. Winding of the lock wire about the spindle displaces the lock wire relative to the implant until the lock wire disengages from the implant. 
     In various embodiments, handle functions, such as steering, reconstraining, and deploying of an expandable implant can be operated by actuating the one or more knobs of the handle, while maintaining the implant at an intermediate configuration within a secondary or intermediate sheath or sleeve, wherein the intermediate configuration is larger than the delivery configuration and smaller than a deployed configuration. For example, the introducer assembly can include a secondary sheath for limiting expansion of the implant to an intermediate configuration after displacement of the constraining sheath. The secondary sheath can include a flexible film constraining sleeve that extends over and releasably constrains the implant. An elongated coupling member, such as a fiber or wire, stitches opposing edges or sides of the constraining sleeve together to releasably constrain the implant toward the intermediate configuration. The constraining sleeve can be opened by de-coupling the coupling member from the constraining sleeve. Further details of materials and general construction of constraining sleeves can be found in U.S. Pat. No. 6,352,561 to Leopold et al. 
     Referring to  FIG. 14 , the sheath  200  and handle  300  can be releasably coupled to each other for subsequent re-use of the sheath  200  as an introducer for other surgical implements after deployment of the device and de-coupling of the handle from the introducer. For example, the introducer and handle can be threaded or keyed with a slot-pin arrangement to form a releasable coupling that allows separation of the handle after deployment of the device and subsequent re-use or re-purposing of the introducer for introducing other surgical implements, such as other devices, tools, probes, cameras, drugs and saline. 
     A catheter assembly in accordance with various embodiments can include tubular first and second catheters in fluid communication with each other, wherein the second catheter includes a port fitting and can be elastically longitudinally strained to cinch the first and second catheters together. An example of such a catheter assembly is shown in  FIGS. 15-16  and generally indicated at  500 . The catheter assembly  500  includes a tubular first catheter  510  having opposite first  512  and second  514  ends, an outer surface  516 , and an inner surface  518  defining a lumen  520  that extends between the first  512  and second  514  ends. A side aperture  522  extends between the outer surface  516  and inner surface  518 . 
     The catheter assembly  500  includes a first port housing  524  along the second end  514  of the first catheter  510 . The first port housing  524  can include a first port  526  for accessing the lumen  520  of the first catheter  510 . 
     The catheter assembly  500  also includes a tubular second catheter  530  having opposite first  532  and second  534  ends, an outer surface  536 , and an inner surface  538  defining a lumen  540  that extends between the first  532  and second  534  ends of the second catheter  530 . The first end  532  of the second catheter  530  terminates along the outer surface  516  of the first catheter  510 . The lumen  540  of the second catheter  530  is in fluid communication with the lumen  520  of the first catheter  510  via the side aperture  522 . 
     The catheter assembly  500  can include a second port housing  560  along the second end  534  of the second catheter  530 . The second port housing  560  can include a second port  564  for accessing the lumen of the second catheter  530 . 
     The catheter assembly  500  includes a cinching mechanism  600  for releasably coupling the first  510  and second  530  catheters utilizing elastic tensioning of the second catheter  530 . More specifically, the cinching mechanism  600  includes a receiver  610  on the first port housing  526  that corresponds in shape and size to at least a portion of the second port housing  560  for receiving and supporting the second port housing  560  thereon. The receiver  610  includes a pair of upstanding walls  612  that are spaced apart to accommodate the second port housing  560  therebetween. At least one of the upstanding walls  612  includes a recess  614 . 
     The cinching mechanism  600  also includes at least one protrusion  630  extending outwardly from the second port housing  560 . The protrusion  630  engages the recess  614  while the second port housing  560  is seated between the upstanding walls  612  of the receiver  610 , as shown in  FIG. 15 . In this seated state, the second catheter  530  is elastically tensioned which creates a reactive force that retains the protrusion  630  within the recess  614 . The second port housing  560  can be unseated from the receiver  610  by pulling and elastically stretching the second catheter  530  along a direction generally indicated at “c” in  FIG. 16  to allow the protrusion  630  to exit the recess  614 . The second port housing  560  and second catheter  530  can then be freely positioned relative to the first port housing  524 . The second port housing  560  can be returned to the seated state by again elastically stretching the second catheter  530 , re-aligning the protrusion  630  with the recess  614  and allowing the second catheter  530  to relax, cinch and thereby maintain the second port housing  560  in the seated state in the receiver  610  of the first port housing  524 . 
     The second catheter  530  can be made from any suitable materials that allow the second catheter  530  to be elastically stretched to create sufficient reactive force to retain the protrusion  630  in the recess  614  while the second port housing  560  is in the seated state; allow the second catheter  530  to be further elastically stretched to allow the protrusion  630  to be displaced from the recess  614  to unseat the second port housing from between the upstanding walls  612  of the receiver  610 ; and yet still provide conventional catheter functions, such as fluid transfer, and delivery of surgical implements and devices. 
     It will be apparent to those skilled in the art that various modifications and variations can be made in the present disclosure without departing from the spirit or scope of the present disclosure. Thus, it is intended that the present disclosure cover the modifications and variations of this present disclosure provided they come within the scope of the appended claims and their equivalents.