Abstract:
Medical systems, devices and methods are provided for engaging tissue, e.g. for clipping tissue, closing a perforation or performing hemostasis. Generally, the medical system including a housing, first and second jaws rotatable relative to the housing, first and second links pivotally attached to the jaws, and a driver. The housing, first and second jaws, and first and second links form a linkage mechanism that allows the jaws to engage tissue and be left in vivo.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application is a Continuation-In-Part of U.S. patent application Ser. No. 12/971,873 filed on Dec. 17, 2010, and also claims the benefit of U.S. Provisional Patent Application Ser. No. 61/391,875 filed on Oct. 11, 2010. All of the foregoing applications are hereby incorporated by reference. 
     
    
     BACKGROUND 
       [0002]    Conventionally, a clip may be introduced into a body cavity through an endoscope to grasp living tissue of a body cavity for hemostasis, marking, and/or ligating. Such clips are often known as surgical clips, endoscopic clips, hemostasis clips and vascular clips. In addition, clips are now being used in a number of applications related to gastrointestinal bleeding such as peptic ulcers, Mallory-Weiss tears, Dieulafoy&#39;s lesions, angiomas, post-papillotomy bleeding, and small varices with active bleeding. Clips have also been attempted for use in closing perforations in the stomach 
         [0003]    Gastrointestinal bleeding is a somewhat common and serious condition that is often fatal if left untreated. This problem has prompted the development of a number of endoscopic therapeutic approaches to achieve hemostasis such as the injection of sclerosing agents and contact thermo-coagulation techniques. Although such approaches are often effective, bleeding continues for many patients and corrective surgery therefore becomes necessary. Because surgery is an invasive technique that is associated with a high morbidity rate and many other undesirable side effects, there exists a need for highly effective, less invasive procedures. 
         [0004]    Mechanical hemostatic devices such as clips have been used in various parts of the body, including gastrointestinal applications. One of the problems associated with conventional hemostatic devices and clips, however, is that many devices are not strong enough to cause permanent hemostasis. Further, clips have also been attempted for use in closing perforations in the stomach or gastrointestinal structures, but unfortunately traditional clips suffer from difficult placement and the capability to grasp a limited amount of tissue, potentially resulting in incomplete closure. 
       SUMMARY 
       [0005]    The invention may include any of the following aspects in various combinations and may also include any other aspect described below in the written description or in the attached drawings. 
         [0006]    In a first aspect, a medical device is provided for engaging tissue, the medical device including a housing, first and second jaws, first and second links, and a driver. The housing defines an internal passageway and a longitudinal axis extending between proximal and distal ends of the housing. The housing also defines a jaw guide surface, a first link guide surface and a second link guide surface, each of the guide surfaces extending longitudinally between proximal and distal ends of the guide surfaces. The first jaw is slidably and pivotally connected to the housing, and has proximal and distal ends. The first jaw is slidably received within the internal passageway for longitudinal movement along the jaw guide surface. The second jaw is slidably and pivotally connected to the housing, and has proximal and distal ends. The second jaw is slidably received within the internal passageway for longitudinal movement along the jaw guide surface. The first link has first and second ends. The first end is pivotally attached to the first jaw, and the second end is slidably and pivotally attached to the housing for longitudinal movement along the first link guide surface. The second link has first and second ends. The first end is pivotally attached to the second jaw, and the second end is slidably and pivotally attached to the housing for longitudinal movement along the second link guide surface. The driver is operatively connected to the first and second jaws, whereby longitudinal movement of the driver moves the first and second jaws longitudinally along the jaw guide surface and moves the second ends of the first and second links along the first and second link guide surfaces. Longitudinal movement of the driver rotates the first and second jaws relative to the housing when the second ends of the first and second links reach the distal ends of the first and second link guide surfaces. 
         [0007]    According to more detailed aspects, the proximal ends of the first and second jaws are slidably and pivotally attached to the housing. Preferably, the proximal ends are pivotally attached to the housing about a shared jaw pivot axis. A jaw pivot pin may be used to pivotally connect the proximal ends of both the first and second jaws to the housing. The jaw guide surface is defined by opposing jaw slots formed in the housing, the opposing jaw slots receiving opposing ends of the jaw pivot pin. Preferably, the jaw guide surface extends longitudinally and parallel to the central axis. The jaw guide surface may be located between the first and second link guide surfaces. The first ends of the first and second links are pivotally attached at a midpoint of the first and second jaws, respectively, while the second ends of the first and second links are slidably and pivotally connected to the housing. 
         [0008]    According to further detailed aspects, the driver is engaged with the proximal ends of the first and second jaws when the driver is moved distally. The driver is engaged with the second ends of the first and second links when the driver is moved proximally. Preferably, the driver includes a distal end for engaging the first and second jaws, the distal end of the driver including a first flange which engages the proximal end of the first jaw and is shaped to permit rotation of the first jaw relative to the first flange while engaged, the distal end of the driver including a second flange which engages the proximal end of the second jaw and is shaped to permit rotation of the second jaw relative to the second flange while engaged. The driver extends longitudinally to a position located proximal to the second ends of the first and second links. 
         [0009]    According to still further detailed aspects, the first and second jaws are longitudinally slidable between an extended position and a retracted position, and the housing is structured to block rotation of the first and second jaws when in their retracted positions, and the housing is structured to permit rotation of the first and second jaws when in their extended positions. The first and second links are also longitudinally slidable between an extended position and a retracted position, and at the same time or alternatively, the housing is structured to block rotation of the first and second links when in their retracted positions, and the housing is structured to permit rotation of the first and second links when in their extended positions. The housing, the first link, and the first jaw are pivotable relative to each other, and the housing, the second link, and the second jaw are pivotable relative to each other, and further the second ends of the first and second links are longitudinally slidable relative to the proximal ends of the first and second jaws, whereby the distance between the second ends and proximal ends determines the rotation of the first and second jaws between a closed configuration and an open configuration. The device may also include an elongate drive wire selectively connected to the driver for longitudinal movement therewith, and an elongate tubular member (e.g. a catheter) selectively connected to the housing. Sufficient proximal translation of the drive wire disconnects the driver from the drive wire and the housing from the elongate tubular member. 
         [0010]    According to more detailed aspects, the device may also include a first link pivot pin that pivotally connects the second end of the first link to the housing, and a second link pivot pin that pivotally connects the second end of the second link to the housing. The first link guide surface is defined by opposing first link slots formed in the housing, and the second link guide surface is defined by opposing second link slots formed in the housing, wherein the opposing first link slots receive opposing ends of the first link pivot pin, and wherein the opposing second link slots receive opposing ends of the second link pivot pin. 
         [0011]    In a second aspect, a method is provided for clamping tissue. The method includes providing a medical device comprising a housing, first and second jaws, first and second links, and a driver, wherein the first and second jaws are slidably and pivotally connected to the housing, the first and second links are slidably and pivotally connected to the housing, the first and second links are pivotally attached to the first and second jaws, respectively, and the driver is operatively connected to the first and second jaws. The driver is advanced distally to translate the first and second jaws and the first and second links distally relative to the housing. The distal translation of the first and second links is limited or blocked while further advancing the driver distally to rotate the first and second jaws relative to the housing. The driver is retracted proximally to rotate the first and second jaws relative to the housing. According to more detailed aspects, the medical device may further comprise an elongated drive wire selectively connected to the driver for longitudinal movement therewith, and the drive wire may be detached from the driver. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0012]    The accompanying drawings incorporated in and forming a part of the specification illustrate several aspects of the present invention, and together with the description serve to explain the principles of the invention. In the drawings: 
           [0013]      FIG. 1  is a top view of a medical system having a medical device for engaging tissue, constructed in accordance with the teachings of the present invention; 
           [0014]      FIG. 2  is a top view similar to  FIG. 1 , but showing the outer structures in dotted lines and the interior sections in solid lines and partial cross-section; 
           [0015]      FIG. 3  is a side view of the medical system and device depicted in  FIG. 1 ; 
           [0016]      FIG. 4  is a side view similar to  FIG. 3 , but showing the outer structures in dotted lines and the interior structures in solid lines and partial cross section 
           [0017]      FIG. 5  is a front perspective view of interior structures of the medical system and device depicted in  FIGS. 1-4 ; 
           [0018]      FIG. 6  is a rear perspective view of interior structures of the medical system and device depicted in  FIGS. 1-4 ; 
           [0019]      FIGS. 7-11  are side views showing operation of the medical system and device depicted in  FIGS. 1-4 ; 
           [0020]      FIGS. 12 and 13  are top views, partially in cross-section, depicting operation of the medical system and device depicted in  FIGS. 1-4 ; and 
           [0021]      FIGS. 14 and 15  are cross-sectional views showing operation of the medical system depicted in  FIGS. 1-4 . 
       
    
    
     DETAILED DESCRIPTION 
       [0022]    The terms “proximal” and “distal” as used herein are intended to have a reference point relative to the user. Specifically, throughout the specification, the terms “distal” and “distally” shall denote a position, direction, or orientation that is generally away from the user, and the terms “proximal” and “proximally” shall denote a position, direction, or orientation that is generally towards the user. 
         [0023]    An exemplary medical system  20  having a medical device  40  for engaging tissue T ( FIG. 11 ) is shown in  FIGS. 1 through 4 . The medical system  20  and device  40  are generally sized and structured for operation through the working channel of an endoscope (not shown) or other scope, although the system  20  and device  40  may also be used alone or in conjunction with other elongate devices such as catheters, fiber-optic visualization systems, needles and the like. Generally, the medical system  20  includes a drive wire  22  slidably housed within the distal end  23  of a catheter  24  for selective connection to, and operation of, the medical device  40 . As will be described in further detail herein, the medical device  40  generally includes a housing  42  having a first jaw  44  and a second jaw  46  pivotally connected thereto for engaging the tissue T. Generally, the jaws  44 ,  46  have been shown as forming grasping forceps, although the jaws are intended to be used to clip tissue, e.g. to close an opening or for hemostasis. Accordingly, it will be recognized that the shape and structure of the jaws may take many forms and serve many purposes and functions, all in accordance with the teachings of the present invention. 
         [0024]    In the medical system  20 , the drive wire  22  slidably extends through the catheter  24 . Although the term “wire” is used to refer to the drive wire  22 , it will be recognized that any elongate control member capable of transmitting longitudinal force over a distance (such as is required in typical endoscopic, laparoscopic and similar procedures) may be used, and this includes plastic rods or tubes, single filament or multi-filament wires and the like. The drive wire  22  should also be capable of properly transmitting a rotational/torsional force from the proximal end to the distal end to rotate the medical device  40  and jaws  44 ,  46 , and thus it is currently preferred that the drive wire  22  is formed from nitinol (e.g. a nitinol wire) or other superelastic alloy. 
         [0025]    A connection block  26  is slidably fitted within the distal end  23  of the catheter  24  and defines a bore  28  therethrough which slidably receives the drive wire  22 . The exterior of the connection block  26  includes a recessed portion  27 , and two pins  30  (e.g., formed from stainless steel wire) are connected to the catheter  24  and positioned within the recessed portion  27  (i.e. between proximal and distal flanges defining the recessed portion  27 ) to limit the longitudinal movement of the connection block  26 . 
         [0026]    A distal end of the drive wire  22  defines a distal head  32  that is sized larger than the drive wire  22 , and likewise larger than the bore  28  in the connection block  26 . As will be described later herein, the distal head  32  is used to slide the connection block  26  within the catheter  24  to disconnect the medical device  40  from the medical system  20 . As also seen in  FIGS. 1-4 , the housing  42  of the medical device  40  is a tubular member defining an interior space  43 . A proximal end of the housing  42  frictionally receives a distal end of the connection block  26  within the interior space  43  for selective connection therewith. 
         [0027]    The internal passageway  43  of the housing  42  also receives the first and second jaws  44 ,  46  and a driver  48  which is used to interconnect the drive wire  22  to the jaws  44 ,  46 . As best seen in  FIG. 5 , the first and second jaws  44 ,  46  include distal ends  60 ,  62  that are structured to grasp and engage tissue, which have a talon shape as disclosed in 61/141,934 filed Dec. 31, 2008, the disclosure of which is incorporated herein by reference in its entirety. Generally, distal translation of the driver  48  causes the first and second jaws  44 ,  46  to rotate outwardly away from each other, while proximal retraction of the driver  48  causes the first and second jaws  44 ,  46  to rotate inwardly toward one another. 
         [0028]    As best seen in  FIGS. 1 ,  2  and  5 - 6 , the driver  48  has a proximal portion which defines a socket  50  sized to receive enlarged distal head  32  of the drive wire  22 . At the proximal entrance of the socket  50 , two deflectable locking tabs  52  are formed which rotate relative to the remainder of the driver  48  to increase or decrease the size of the socket  50 . The locking tabs  52  may be separately formed and pivotally attached to the driver  48 , or may be integrally formed with the driver  48  and formed of a resilient material which flexes to permit rotation of the locking tabs  52  radially inwardly and radially outwardly. Preferably the locking tabs  52  are plastically deformable, such that they may be locked to the drive wire  22  or to the housing  42 , as discussed further herein. 
         [0029]    As best seen in  FIGS. 5-6 , a distal portion of the driver  48  defines a two L-shaped flanges  56 ,  58  for engaging and operating the jaws  44 ,  46 . The inner surface of flange  56  engages a proximal end  66  of jaw  46 , while the inner surface of flange  58  engages a proximal end  64  of jaw  44 . The flanges  56 ,  58  are shaped to permit rotation of the proximal ends  64 ,  66  of the jaws  44 ,  46  relative to the flanges  56 ,  58  while engaged therewith. While the flanges  56 ,  58  and proximal ends  64 ,  66  have been shown as squared-off (so that they firmly engage in the fully open, and fully closed, positions), the mating surfaces may be rounded or otherwise shaped to promote rotation between the flanges  56 ,  58  and the proximal ends  64 ,  66  of the jaws  44 ,  46 . 
         [0030]    The proximal ends  64 ,  66  of jaws  44 ,  46  are pivotally attached to the housing  42  directly via a pin  49  which extends through the proximal ends  64 ,  66  and through opposing jaw slots  86  formed in the housing, as best seen in  FIGS. 3-4 . By virtue of the jaw slots  86 , the jaws  44 ,  46  are thus both pivotally, and slidably, attached to the housing  42 . The opposing jaw slots  86  thus act and define a jaw guide surface of the housing  42  which guides longitudinal movement of the jaws  44 ,  46  relative to the housing. The distal ends of the jaw slots  86  also serve to restrict the longitudinal movement of the jaws  44 ,  46  relative to the housing  42 . It will be recognized that the jaw guide surface could also be formed by channels, recesses or other structures formed into the housing  42 , instead of, or in conjunction with, the jaw slots  86 . During assembly, the slots allow the pins of the device  40  to be inserted after the jaws, links and driver are positioned with the housing, and the slots may later be covered with a sleeve, strip, secondary housing or other material if desired. 
         [0031]    Turning back to  FIGS. 5 and 6 , the first and second jaws  44 ,  46  are also indirectly connected to the housing  42  via first and second links  68 ,  70 , respectively. Distal ends of the first and second links  68 ,  70  are pivotally attached to first and second jaws  44 ,  46  via pivots  81 . The pivotal connections (pivots  81 ) are formed at a midpoint of the first and second jaws  44 ,  46 , i.e. anywhere between the proximal ends  66 ,  68  and the distal ends  60 ,  62  of the first and second jaws  44 ,  46 . The proximal ends of the first and second links  68 ,  70  are slidably and pivotally attached to the housing  42  via two pins  80 . In particular, and as best seen in  FIGS. 3-4 , the housing  42  defines opposing first link slots  82  that are sized and positioned to receive the pin  80  of the first link  68 , as well as opposing second link slots  84  that are sized and positions to receive the pin  80  of the second link  70 . In  FIGS. 1-2 , the opposing first link slots  82  are individually identified by reference numerals  82   a  and  82   b.  Accordingly, the opposing first and second link slots  82 ,  84  act and define first and second link guide surfaces of the housing  42  which guide longitudinal movement of the first and second links  68 ,  70  relative to the housing  42 . As with the jaw guide surface, the first and second link guide surfaces could also be formed by channels, recesses or other structures formed into the housing  42 , instead of, or in conjunction with, the first and second link slots  82 ,  84 . 
         [0032]    The driver  48  extends between the proximal ends of the first and second links  68 ,  70 , and engages the proximal ends  64 ,  66  of the first and second jaws  44 ,  46  to first expose and then open the jaws  44 ,  46 , as shown in  FIGS. 5 and 6 . At the same time, the proximal ends of the links  68 ,  70  and their pins  80  are located such that proximal retraction of the driver  48  (via drive wire  22 ) causes the outer surface of the L-shaped flanges  56 ,  58  to engage the pins  80  (or links  68 ,  70 ) for retraction and closing of the jaws  44 ,  46 , as will be described in further detail below. It can thus be seen that the jaw guide surface of slot  86  is located between the first and second link guide surfaces of slots  82 ,  84  (which are above and below the slot  86 ), as best seen in  FIGS. 3-4 . 
         [0033]    The internal passageway  43  of the housing  42  extends through the distal end of the housing  42 , and it is through this passageway  43  that the first and second jaws  44 ,  46  can extend. Additionally, as shown in  FIGS. 1-4 , the housing  42  defines opposing slots  45  which are sized to permit the first and second jaws  44 ,  46  and the first and second links  68 ,  70  to pass therethrough when they rotate radially outwardly. Accordingly, it is also clear from  FIGS. 1 and 2  that the housing  42  serves to block rotation of the first and second links  68 ,  70  when they are entirely or partially contained within the internal passageway  43  of the housing  42 . Suitable plastics for forming the housing include, but are not limited to, polytetrafluorethylene (PTFE), expanded polytetrafluorethylene (EPTFE), polyethylene ether keytone (PEEK), polyvinylchloride (PVC), polycarbonate (PC), polyamide, polyimide, polyurethane, polyethylene (high, medium or low density), and suitable metals include stainless steel, nitinol and similar medical grade metals and alloys. 
         [0034]    Turning to the sequence of  FIGS. 7-11 , operation of the medical device  40  will now be described. As shown in  FIG. 7 , the first and second jaws  44 ,  46  are shown in a retracted position where they are substantially contained within the housing  42 . Depending on the application, the distal ends  60 ,  62  of the jaws  44 ,  46  may slightly project from the distal end of the housing  42  in their retracted positions, or they may be entirely positioned within the housing  42 . When the drive wire  22  is translated distally (to the left on the page in  FIG. 7 ) the distal head  32  engages the driver  48 , which in turn engages the proximal ends  64 ,  66  of the jaws  44 ,  46  (via the driver&#39;s flanges  56 ,  58  (FIGS.  5 - 6 )), causing the jaws  44 ,  46  to slide distally through and out of the housing  42 , as shown in  FIG. 8 . As previously mentioned, this longitudinal movement is guided by the jaw guide surface of jaw slot  86  (receiving pin  49 ), and the link guide surfaces of link slots  82 ,  84  (receiving pins  80 ) which slidably and pivotally connect the jaws  44 ,  46  to the housing  42 . 
         [0035]    As shown in  FIG. 8 , the first and second jaws  44 ,  46  have an extended position where the jaws substantially project from a distal end of the housing  42 . In this extended position, the pins  80  at the proximal ends of the first and second links  68 ,  70  have reached the end of their slots  82 ,  84 , while the pin  49  at the proximal ends  64 ,  66  of the jaws  44 ,  46  have not reached the end of slot  86 . Accordingly, it will be seen that further distal advancement of drive wire  22 , and hence the driver  48 , causes the proximal ends  64 ,  66  of jaws  44 ,  46  to continue moving distally (to the left on the page), while the links  68 ,  70  induce rotation of the jaws  44 ,  46  away from each other, as shown in  FIG. 9 . Eventually, the pin  49  reaches the end of jaw slot  86 , at which point the jaws  44 ,  46  are fully open. The jaws  44 ,  46  have been shown rotating about 75°, thus forming a 150° opening between them, however the housing  42  and its slots may be sized to permit rotation through a full 90° or more, thus forming at least a 180° between them. The slots  45  in the housing  42  are sized to permit the rotation of the jaws  44 ,  46  and links  68 ,  70  out of the housing, and these slots  45  may also be used to limit the rotation thereof, in addition to or separately from the sizing of the slots  82 ,  84 ,  86 . It will therefore be seen that the distance between the pins  80  (at the ends of the first and second links  68 ,  70 ) and the proximal ends  64 ,  66  of the jaws  44 ,  46  determines the rotation of the first and second jaws between a closed configuration and an open configuration. 
         [0036]    In the tissue receiving configuration (open configuration) shown in  FIG. 9 , the medical device  40  and its jaws  44 ,  46  may be positioned adjacent tissue T. As shown in  FIG. 10 , the tissue T may be placed between the first and second jaws  44 ,  46  and the jaws  44 ,  46  rotated back towards their position shown in  FIG. 8 . The tissue T has been shown as a single layer, although multiple layers may be clipped between the jaws  44 ,  46 . Generally, proximal retraction of the drive wire  22  and the driver  48  causes the flanges  56 ,  58  of the driver  48  to engage the pins  80  at the proximal ends of the links  68 ,  70 . In particular, as also clear from  FIGS. 5 and 6 , the flange  56  will engage pin  80  of the first link  68 , and flange  58  will engage pin  80  of second link  70 . As the links  68 ,  70  are pulled proximally (to the right on the page) the housing  42  presses on the links  68 ,  70  (and/or the jaws  44 ,  46 ) and causes them to rotate towards each other to grasp the tissue T therebetween. Depending on their orientation relative to the patient and the ground, the jaws  44 ,  46  may also naturally collapse towards each other. As shown in  FIG. 11 , further proximal retraction of the drive wire  22  and driver  48  will cause the jaws  44 ,  46  to move longitudinally in a proximal direction (to the right on the page in  FIG. 11 ). 
         [0037]    In order for the medical device  40  to serve as a clip and maintain its grasp on the tissue T, or to maintain the clipping of two layers of tissue against each other, the jaws  44 ,  46  may be locked in position and the drive wire  22  of the medical system  20  disconnected from the medical device  40 . As shown in  FIG. 12 , the interior of the housing  42  also defines a driver guide surface  88  (which guides the driver  48 ) that has a proximal portion  88   p  and a distal portion  88   d.  The proximal portion  88   p  of the driver guide surface  88  has a width (measured up and down on the page in  FIG. 12 ) that is greater than a width of the distal portion  88   d  of the driver guide surface  88 . The driver guide surface  88  may be formed by opposing surfaces or C-shaped channels in the housing  42 . The transition between the proximal portion  88   p  and distal portion  88   d  defines a shoulder  89 , and namely two shoulders  89   a,    89   b  on opposing sides of the housing  42 . The shoulders  89   a,    89   b  are sized and positioned to engage the locking tabs  52  located on the driver  48 . 
         [0038]    As shown in  FIG. 12 , when the driver  48  is located within the distal portion  86   d  of the third guide surface  86 , the locking tabs  52  are forced radially inwardly into firm frictional engagement with the enlarged head  32  and/or the drive wire  22 . Stated another way, the socket  50  formed by the driver  48  that receives the distal head  32  has an entrance which is narrowed by the inward deflection of the locking tabs  52 . In this state depicted in  FIG. 12 , the drive wire  22  is firmly engaged with the driver  48  and hence the first and second jaws  44 ,  46 . When the drive wire  22  and driver  48  are retracted proximally, for example upon grasping tissue as shown in  FIG. 11 , the proximal end of the driver  48  is received within the proximal portion  88   p  of the third guide surface  88  which has a larger width that permits outward movement of the locking tabs  52 . Accordingly, in the state depicted in  FIG. 13 , the locking tabs  52  may be loosely and detachably connected to the distal head  32  of the drive wire  22 . As such, further proximal movement of the drive wire  22  and its distal head  32  may be used to withdraw the distal head  32  from the socket  50  of the driver  48 . At the same time, the locking tabs  52  move radially outwardly and into engagement with the shoulders  89   a ,  89   b  to lock the device  40  in a state where the tissue T is clipped between the jaws  44 ,  46 . The tabs  52  may plastically deform to this outward position to maintain the closed configuration of the jaws. In the event the natural elasticity of the tissue T tends to pull the jaws  44 ,  46  out from the housing towards their extended position, the locking tabs  52  will abut the shoulders  89  of the driver guide surface of the housing  42  to prevent further distal movement or rotation of the jaws  44 ,  46 . 
         [0039]    Turning now to  FIGS. 14 and 15 , upon still further proximal retraction of the drive wire  22  and distal head  32  (to the right on the page), the enlarged distal head  32  (or other enlarged portion of the drive wire  22 ) will abut the connection block  26 , which is slidably fitted within the distal end  23  of the catheter  24 . Sufficient proximal force on the drive wire  22  will overcome the frictional fit between the connection block  26  and the proximal end of the housing  42 , thus moving the connection block  26  proximally to retract the connection block  26  within the tubular connector  24 , as shown in  FIG. 15 . The catheter  24  can be used to provide a counterforce on the housing  42  while proximally retracting the drive wire  22  and connection block  26 . Accordingly, the drive wire  22 , catheter  24  and connection block  26  may be fully disconnected from the medical device  40 , thereby leaving the first and second jaws  44 ,  46  and the housing  42  in a state having the tissue T clipped between the jaws  44 ,  46  and retained in vivo. The connection block  26  is retained at the distal end  24  of the catheter  24  via the pins  30 , which are positioned within the recessed area  27  to engage the proximal and distal ends of the connection block  26  and limit its longitudinal movement. 
         [0040]    The elongate catheter  24  (or other elongate tubular member such as a sheath, tube, scope or the like), which slidably encases the drive wire  22 , extends proximally therealong to a proximal end of the system  20 , and has a length suitable for placing the device  40  at any desire location within the body, while the proximal ends of drive wire  22  and catheter  24  are positioned outside of the body for use by the medical professional. Control handles (not shown) for controlling relative translation of the drive wire  22  and catheter  24  are well known in the art, and may be employed at the proximal end of the system  20 . Additional embodiments of the connection/disconnection mechanisms and the medical system  20  may be found in copending U.S. Appl. No. 61/391,878 and Appl. No. 61/391,881, the disclosures of which are hereby incorporated by reference in their entirety. 
         [0041]    The foregoing description of various embodiments of the invention has been presented for purposes of illustration and description. It is not intended to be exhaustive or to limit the invention to the precise embodiments disclosed. Numerous modifications or variations are possible in light of the above teachings. The embodiments discussed were chosen and described to provide the best illustration of the principles of the invention and its practical application to thereby enable one of ordinary skill in the art to utilize the invention in various embodiments and with various modifications as are suited to the particular use contemplated. All such modifications and variations are within the scope of the invention as determined by the appended claims when interpreted in accordance with the breadth to which they are fairly, legally, and equitably entitled.