Abstract:
An apparatus for gathering of tissue of a heart valve leaflet comprises an elongated member and a grasping assembly movable in the elongated member between a retracted position and an extended position. The grasping assembly includes an actuating arm having a proximal end and a distal end. The grasping assembly is attached to the distal end of the activating arm. The grasping assembly is operable to gather and clamp the tissue of the heart valve leaflet such that clamped tissue has a gathered configuration.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
       [0001]    The application claims the benefit of the filing date of the U.S. Provisional Patent Application No. 61/770,612, filed on Feb. 28, 2013, the disclosure of which application is hereby incorporated by reference in its entirety. 
     
    
     BACKGROUND OF THE INVENTION 
       [0002]    The present disclosure is related to heart valve repair, and more particularly to devices, systems, and methods for transcatheter repair of a heart valve leaflet. 
         [0003]    Properly functioning heart valves can maintain unidirectional blood flow in the circulatory system by opening and closing, depending on the difference in pressure on each side of the valve. The two atrioventricular valves (mitral and tricuspid valves) are multicusped valves that prevent backflow from the ventricles into the atria during systole. They are anchored to the wall of the ventricle by chordae tendineae, which prevent the valve from inverting. 
         [0004]    The mitral valve is located at the gate of the left ventricle and is made up of two leaflets and a diaphanous incomplete ring around the valve, known as the mitral valve annulus. When the valve opens, blood flows into the left ventricle. After the left ventricle fills with blood and contracts, the two leaflets of the mitral valve are pushed upwards and close, preventing blood from flowing back into the left atrium and the lungs. 
         [0005]    Mitral valve prolapse is a type of myxomatous valve disease in which the abnormal mitral valve leaflets prolapse (i.e., a portion of the affected leaflet may be billowed, loose, and floppy). Furthermore, the chordae tendineae may stretch and thus become too long, or the chordae tendineae may be broken. As a result, the valve does not close normally, and the unsupported valve leaflet bulges back, or “prolapses,” into the left atrium like a parachute. Thus, as the ventricle contracts, the abnormal leaflet may be propelled backwards, beyond its normal closure line into the left atrium, thereby allowing blood to flow back into the left atrium and the lungs. 
         [0006]    Mitral valve prolapse causes mitral regurgitation. Isolated posterior leaflet prolapse of the human heart mitral valve, i.e., prolapse of a single leaflet, is the most common cause of mitral regurgitation. The exact cause of the prolapse is not clear. Untreated mitral regurgitation may lead to congestive heart failure and pulmonary hypertension. 
         [0007]    Despite the various improvements that have been made to devices and methods for mitral valve leaflet repair, there remain some shortcomings. For example, conventional methods of treating mitral valve prolapse include replacement of the mitral valve, clipping the two mitral valve leaflets to one another, and resection of the prolapsed segment using open heart surgery. Such surgical methods may be invasive to the patient and may require an extended recovery period. 
         [0008]    There therefore is a need for further improvements to the current techniques for treating heart valve leaflet prolapse. Among other advantages, the present invention may address one or more of these needs. 
       BRIEF SUMMARY OF THE INVENTION 
       [0009]    An embodiment according to the disclosure includes a heart valve repair apparatus includes an elongated member configured for a transcatheter operation and a grasping mechanism including at least first, second, and third fingers, disposed at a distal end of the elongated member and configured to gather a tissue of the heart valve in a generally U-shaped pleat. The apparatus further includes an actuating rod coupled to the grasping mechanism and configured to urge at least the first finger to move away from the second and third fingers, thereby defining an opening within which a heart tissue may be received and to urge the first finger between the second and third fingers to gather the heart tissue in a pleated configuration. The apparatus includes an outer tube movably mounted to the elongated member and having a bore extending therethrough. The outer tube, in a first position thereof, is configured, to substantially enclose a distal end of the elongated member and the grasping mechanism in the bore thereof and, in a second position thereof, to substantially uncover the distal end of the elongated member and the grasping mechanism, thereby deploying the grasping mechanism in an expanded condition for gathering the tissue. The apparatus further includes a clip movably mounted on the elongated member and configured to capture and retain the heart tissue in the pleated configuration. 
         [0010]    Another embodiment according to the disclosure includes a clip for mitral valve repair, which clip comprises a generally cylindrical hollow base; and first and second tines extending from said cylindrical base in a generally V-shaped configuration, wherein a recess is defined in said cylindrical base between and adjacent to said first and second tines, and wherein said cylindrical base comprises a raised section extending from said recess to an edge of said cylindrical base distal to said first and second tines. Each of the first and second tines comprises first and second projections, respectively, oriented proximate one another, such that when the first and second projections are urged against a boss, the boss causes the first and second projections to move away from each other. 
         [0011]    According to an aspect of the disclosure, a transcatheter method for gathering tissue of a heart valve leaflet includes inserting an elongated catheter assembly to a position adjacent the heart valve leaflet. The catheter assembly comprises an activating arm, and a grasping assembly extending from a distal end of the activating arm. The grasping assembly has a retracted position and an extended position. The method further comprises causing the grasping assembly to deploy from the retracted position to the extended position for gathering the tissue in a gathered configuration. The grasping assembly comprises a plurality of fingers, wherein the plurality of fingers are configured to move away from one another in an expanded configuration thereof and to move toward one another in a collapsed configuration thereof. The catheter assembly further comprises a clip positioned along the activating arm, the clip comprising a generally cylindrical hollow base and first and second tines extending from the generally cylindrical base in a generally V-shaped configuration. 
         [0012]    According to an embodiment of the disclosure, a heart valve repair apparatus includes an elongated member configured for a transcatheter operation, a grasping mechanism including at least first, second, and third fingers, disposed at a distal end of the elongated member and configured to gather a tissue of the heart valve in a generally U-shaped pleat, an actuating rod coupled to the grasping mechanism and configured to urge at least the first finger to move away from the second and third fingers, thereby defining an opening within which a heart tissue may be received and to urge the first finger between the second and third fingers to gather the heart tissue in a pleated configuration, an outer tube movably mounted to the elongated member and having a bore extending therethrough, and a clip movably mounted on the elongated member and configured to capture and retain the heart tissue in the pleated configuration. In a first position thereof, the outer tube is configured to substantially enclose a distal end of the elongated member and the grasping member and the grasping mechanism in the bore thereof. In a second position thereof, the outer tube is configured to substantially uncover the distal end of the elongated member and the grasping mechanism, thereby deploying the grasping mechanism in an expanded condition for gathering the tissue. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0013]    Various embodiments of the present disclosure will now be discussed with reference to the appended drawings. It is to be appreciated that these drawings depict only some embodiments of the disclosure and are therefore not to be considered limiting of its scope. 
           [0014]      FIG. 1  is a diagrammatic perspective view of the posterior leaflet of a mitral valve; 
           [0015]      FIG. 2  is a perspective view of the distal end of a device for heart valve repair according to an embodiment, the device being in a collapsed configuration; 
           [0016]      FIG. 3  is a perspective view of the device of  FIG. 2  in an expanded configuration; 
           [0017]      FIG. 4  is a longitudinal cross-sectional view of the distal end of the device of  FIG. 2 ; 
           [0018]      FIG. 5  is a perspective view of a handle for the device of  FIG. 2 ; 
           [0019]      FIG. 6  is a longitudinal cross-sectional view of the handle of  FIG. 5 ; 
           [0020]      FIG. 7  is a highly schematic perspective view showing the use of the device of  FIG. 2  to repair a heart valve leaflet; 
           [0021]      FIG. 8  is a highly schematic enlarged perspective view of the grasping mechanism of the device of  FIG. 2  gathering the tissue of a heart valve; 
           [0022]      FIG. 9  is a cross-sectional end view of the heart valve tissue gathered by the device of  FIG. 2  to form a generally U-shaped pleat; 
           [0023]      FIGS. 10-12  are perspective views showing the use of the device of  FIG. 2  to deploy a clip for clamping or capturing the tissue in the gathered configuration. 
       
    
    
     DETAILED DESCRIPTION 
       [0024]    As used herein, the terms “proximal” and “distal” are to be taken as relative to a user (e.g., a surgeon or an interventional cardiologist) using the disclosed transcatheter devices. “Proximal” is to be understood as relatively close to the user and “distal” is to be understood as relatively farther away from the user. The invention will be described in connection with the repair of a mitral valve leaflet, but it may be useful in the repair of other types of cardiac valves or in the gathering and clamping of other types of loose body tissue. 
         [0025]    Described below are an apparatus and method for heart valve repair.  FIGS. 2 and 3  illustrate the grasping mechanism  22  in a retracted and a deployed configuration, respectively, whereas  FIG. 4  illustrates a cross-sectional view of the grasping assembly  23 .  FIGS. 5 and 6  illustrate two different views of the handle  60  configured for controlling and operating the heart repair apparatus.  FIGS. 7-9  illustrate various operational stages of the grasping mechanism  22  while gathering the tissue.  FIGS. 10-11  illustrate the deployment of the clip  28  to capture the tissue gathered by the grasping mechanism  22 . Finally,  FIG. 12  illustrates the clip  28  having captured the tissue in a gathered configuration, thereby reducing the prolapse in the heart tissue. The various elements of the apparatus and the operational stages of the apparatus are described in further detail below. 
         [0026]    Referring to  FIG. 1 , an exemplary mitral valve  1  includes posterior leaflet  2  and anterior leaflet  3 . Leaflets  2  and  3  extend from annulus  4  to coaptation line  5  where the leaflets meet. Posterior leaflet  2  has upper portion  6  that is generally perpendicular to the direction of blood flow through valve  1  and extends between annulus  4  and coaptation line  5 . Additionally, posterior leaflet  2  has lower portion  7  that is generally parallel to the direction of blood flow through valve  1  and that extends below coaptation line  5 . Chordae tendineae (not shown) may connect lower portion  7  of posterior leaflet  2  to the papillary muscles (not shown) of the left ventricle (not shown). Posterior leaflet  2  has three scalloped portions P1, P2, and P3, any of which may include a portion that is billowed, loose, or floppy, and which therefore may be the cause of a prolapse condition of the valve. The inventive devices, systems, and methods described herein may be adapted to repair such a billowed, loose, or floppy portion of posterior leaflet  2  or anterior leaflet  3 . 
         [0027]    Referring to  FIGS. 2-4 , the distal portion of an exemplary device  10  for transcatheter gathering of heart valve leaflet tissue includes elongated catheter assembly  12  adapted to be inserted through the apex of a human heart so that distal portion  14  of the catheter assembly may reach the patient&#39;s mitral valve  1  for repair thereof. Catheter assembly  12  includes outer elongated tube  18  and grasping assembly  23  slidably disposed within the outer tube. Grasping assembly  23  includes elongated actuating rod  37  and grasping mechanism  22  attached to distal end  20  of the actuating rod, as seen in  FIG. 4 . Grasping assembly  23  is longitudinally slidable within outer tube  18  between an initial or retracted position (not shown) in which grasping mechanism  22  lies within the outer tube and a deployed position ( FIG. 3 ) in which the grasping mechanism protrudes distally beyond the distal end of the outer tube. As discussed in detail below, grasping mechanism  22  can grasp and fold at least a portion of leaflet  2 . Outer tube  18  or one or more of the components forming distal portion  14  of catheter assembly  12  may be wholly or partly made of one or more echogenic materials so that device  10  can be more easily visualized inside a patient using three-dimensional echocardiography. 
         [0028]    As seen in  FIGS. 2-4 , grasping assembly  23  includes coupler  24  attached to distal end  20  of elongated member  16  which is slidably received within outer tube  18 . Coupler  24  mechanically connects actuating rod  37  to a plurality of fingers  26 , which define grasping mechanism  22 . Fingers  26  extend distally from coupler  24  and are pivotably connected to the coupler so as to move between a collapsed configuration ( FIG. 2 ) and an expanded configuration ( FIG. 3 ). 
         [0029]    In an exemplary embodiment, grasping mechanism  22  may include three fingers  26   a ,  26   b , and  26   c . It is noted here that other embodiments may include more than three fingers, for example, four fingers or five fingers as well. Three fingers  26   a ,  26   b , and  26   c  are capable of moving relative to one another to provide a space therebetween for gathering the tissue of the heart valve leaflet. For example, upon movement of outer tube  18  relative to grasping assembly  23 , thereby exposing grasping assembly  23 , fingers  26   a ,  26   b  and  26   c  may move outwardly away from one another. On the other hand, when outer tube  18  is moved distally relative to grasping assembly  23  (or the grasping assembly is retracted proximally relative to the outer tube) to place the grasping assembly in a retracted position, as partially shown in  FIG. 2 , distal end  18  of the outer tube contacts fingers  26  and urges them toward one another until fingers  26  achieve the collapsed configuration. Once fingers  26  are in the collapsed configuration, grasping assembly  23  may be retracted fully into outer tube  18 . 
         [0030]    In the collapsed configuration, fingers  26  are immediately adjacent and substantially parallel to one another so as to occupy a minimum transverse cross-section, allowing confinement within outer tube  18 . This enables fingers  26  to slide into outer tube  18  in the retracted position. On the other hand, when outer tube  18  is retracted proximally relative to grasping assembly  23  (or the grasping assembly is advanced distally relative to the outer tube) to place grasping mechanism  22  in the deployed position, fingers  26  move outwardly away from one another to the expanded configuration having a much larger transverse cross-section. A spring or other biasing element (not shown) disposed within coupler  24  (or between fingers  26 ) may bias at least fingers  26   a  and  26   c  toward their expanded condition, in which fingers  26   a  and  26   c  diverge from each other in a generally “V-shaped” configuration. The angle between fingers  26   a  and  26   c  in the expanded condition may be an acute angle. Finger  26   b , which is disposed between fingers  26   a  and  26   c , may move from its retracted position to its expanded position upon actuation of grasping assembly  23 . 
         [0031]    With reference to  FIG. 4 , finger  26   b  is attached to actuating rod  37  at least partially disposed within elongated member  16 . Specifically, actuating rod  37  is positioned in bore  38  extending through elongated member  16  and can move longitudinally relative to the elongated member between a retracted position and an actuated position. Since actuating rod  37  is attached to finger  26   b , moving the actuation rod away from grasping mechanism  22  urges finger  26   b  in the direction of arrow C to move from the collapsed condition to the expanded condition, as shown in phantom. Conversely, moving actuating rod  37  toward grasping mechanism  22  causes finger  26   b  to move to the collapsed position illustrated in  FIG. 4 . 
         [0032]    Catheter assembly  12  may include biocompatible clip  28  slidably mounted on the distal end of elongated member  16  and adapted for application to a tissue, such as the tissue of leaflet  2 . Clip  28  may include generally cylindrical base  30  sized to be assembled in friction fit around elongated member  16  and a plurality of tines  32  protruding from the cylindrical base. When clip  28  is positioned on elongated member  16 , tines  32  may rest on the outer surface of the elongated member. Clip  28  may include first and second tines  32  oriented at an acute angle relative to one another, e.g., in a generally V-shaped configuration. Clip  28 , or at least tines  32 , may be wholly or partly made of a resilient material. Free ends  50  of tines  32  may be sharp in order to pierce tissue. In an exemplary embodiment, tines  32  may further or alternatively include features such as teeth or barbs (not shown) along the inner edges for holding clip  28  to the tissue captured therebetween. In the illustrated embodiment, tines  28  are curved towards tips  50 , in which case the clamping force of clip  28  is concentrated as a compressive force at the tips. In another embodiment, tines  32  may comprise uniform or flat inner edges, wherein the tines would exert a generally uniform force over the entire area of the captured tissue. Tines  32  may be configured to diverge from each other such that free ends  50  of tines  32  may expand to a width generally equal to the width between the free ends of fingers  26   a ,  26   c  in their expanded condition. In an exemplary embodiment, tines  32  may have a length generally equal to the length of fingers  26 . It is noted here that the longer the tines  32 , the farther away from base  30  is the contact with the tissue, thereby lessening the mechanical advantage of clip  28  holding the tissue. The appropriate length of tines  32  may be determined by material properties of the material from which clip  28  is made and the desired force to hold the tissue. 
         [0033]    As is seen more clearly in  FIGS. 10 and 11 , tines  32  of clip  28  are spaced from one another at their connection to base  30  of the clip so as to define recess  34  between them. Recess  34  is sized to receive boss  42  that projects radially from connection segment  40  ( FIG. 4 ) as described in detail below. Coupler  24  further has hole  36  sized to receive boss  42  ( FIG. 3 ). Base  30  further includes outwardly raised section  35  ( FIG. 11 ) extending from recess  34  to an edge of the base. Raised section  35  is sized to slide over boss  42 . 
         [0034]    With continued reference to  FIGS. 10 and 11 , catheter assembly  12  further includes shaft  48  positioned along elongated member  16 . In some embodiments, shaft  48  may be disposed on the top of elongated member  16 . Regardless, shaft  48  can move longitudinally relative to elongated member  16  and is in contact with clip  28  when clip  28  has not been deployed. Specifically, shaft  48  may be adapted to contact cylindrical base  30  of clip  28  and, consequently, can urge clip  28  forward in the direction indicated by arrow A when shaft  48  is moved toward fingers  26  of catheter assembly  12 . 
         [0035]    In accordance with another embodiment, actuation rod  37  may be attached to finger  26   b  through connection segment  40 . Boss  42  extends substantially perpendicular from a middle portion of connection segment  40  and may protrude out through hole  36  ( FIG. 3 ) of coupler  24  in certain predetermined positions of finger  26   b , as set forth in detail below. In the retracted position of fingers  26   a ,  26   b , and  26   c , boss  42  is generally flush with the outer diameter of elongated member  16 . Roller  44  may be connected to an end of connection segment  40  and is adapted to roll along the inner surfaces of coupler  24 . Bar  46  may extend substantially vertically from roller  44  and may be directly connected to actuating rod  37 . These components of connection segment  40  may be formed as a one-piece integral body. 
         [0036]    As described in detail below, moving actuating rod  37  away from coupler  24  causes roller  44  to roll toward the free end of the coupler. In turn, this motion of roller  44  urges finger  26   b  to pivot upwardly to the expanded condition as shown in phantom in  FIG. 4 . In addition, when roller  44  rolls toward the free end of coupler  24 , boss  42  moves downwardly through hole  36  in the coupler. On the other hand, moving actuating rod  37  in the opposite direction towards the free end of coupler  24  causes roller  44  to roll away from the free end of the coupler. When roller  44  rolls away from the free end of coupler  24 , boss  42  moves upwardly so as to project out from hole  36 . This motion of roller  44  urges finger  26   b  to pivot downwardly to the collapsed condition shown in  FIG. 4 . Further motion of roller  44  away from the free end of coupler  24  causes finger  26   b  to pivot downwardly to a deployed configuration shown in  FIGS. 8 and 9 , for example. In the deployed configuration boss  42  extends out from hole  36 . 
         [0037]    With reference to  FIGS. 5 and 6 , device  10  further includes handle  60  at proximal end  19  of outer tube  18 . Handle  60  may include first button  61  for controlling actuating rod  37 , second button  64  for controlling outer tube  18 , and third button  66  for deploying clip  28 . 
         [0038]    First button  61  is moveable longitudinally relative to handle  60  and to second button  64 . First button  61  may be attached to actuating rod  37 , such that sliding movement of first button  61  in a proximal or distal direction results in a corresponding sliding movement of actuating rod  37 . 
         [0039]    Second button  64  may be moveable longitudinally relative to handle  60  for controlling the movement of outer tube  18  relative to elongated member  16 . Second button  64  may be attached to one end of linkage  65 , the other end of which may be attached to outer tube  18 , such that sliding movement of second button  64  in a proximal or distal direction results in a corresponding sliding movement of outer tube  18 . 
         [0040]    Third button  66  may have a trigger shape and may be connected at one end to handle  60  by pivot pin  67  that allows for movement of third button  66  in a lateral direction relative to the longitudinal axis of handle  60  for controlling the movement of shaft  48  ( FIG. 10 ) relative to outer tube  18 . Spring  68  may bias third button  66  to return to its initial position after third button  66  has been actuated. Opposite end  69  of third button  66  may be pivotally coupled to a linkage assembly including first linkage  70 , second linkage  71 , and third linkage  72 , all of which are pivotally connected to one another in series. Third linkage  72  may be attached to a proximal end of shaft  48 , such that actuation of third button  66  may cause third linkage  72  to slide proximally to urge shaft  48  distally and thereby deploy clip  28 . 
         [0041]    A description of the use of catheter assembly  12  now follows in accordance with one embodiment of the invention. With reference to  FIGS. 7-12  illustrating various stages of deployment of catheter assembly  11 , the catheter assembly may be used to repair a heart valve, such as mitral valve  1 . Catheter assembly  12  may be introduced into a patient using any known procedures. For example, the user may insert at least the distal end of catheter assembly  12  percutaneously using the femoral approach. Preferably, catheter assembly  12  may be inserted into a patient&#39;s body with grasping mechanism  22  in the collapsed configuration ( FIG. 2 ). Once the distal end of catheter assembly  12  has reached the desired site (i.e., adjacent leaflet  2 ) grasping mechanism  22  may be deployed to its expanded configuration ( FIG. 3 ). As discussed above, to deploy grasping mechanism  22  from the collapsed configuration ( FIG. 2 ) to the expanded configuration ( FIG. 3 ), outer tube  18  is moved proximally (i.e., toward handle  60 ) relative to elongated member  16  to its retracted position. In an exemplary embodiment, the user may move outer tube  18  to the retraced position by moving second button  64  toward free end  80  of handle  60 . 
         [0042]    When outer tube  18  is in the retraced position, at least fingers  26   a  and  26   c  automatically move laterally away from finger  26   b  ( FIG. 3 ) in the direction indicated by arrows X and define a first plane. Fingers  26   a  and  26   c  form an angle therebetween. Finger  26   b  may also move automatically in the direction indicated by arrow Y upon movement of outer tube  18  to the retracted position. Alternatively, finger  26   b  may move in the direction indicated by arrow Y by moving actuating rod  37  toward handle  60 . To move actuating rod  37  toward handle  60 , the user may move first button  61  toward free end  80  of handle  60 . Finger  26   b , thus, pivotally moves in a plane generally perpendicular to the first plane defined by fingers  26   a  and  26   c , in an exemplary configuration. 
         [0043]    Once grasping mechanism  22  is in the expanded configuration, fingers  26  of catheter assembly  12  may be placed surrounding at least a portion of leaflet  2 , as shown in  FIGS. 8 and 10 . Fingers  26   a  and  26   c  are generally on one side of the tissue of leaflet  2 , whereas finger  26   b  is on the opposing side of the tissue of the leaflet. Finger  26   b  is then pivoted about coupler  24  beyond the first plane defined by fingers  26   a  and  26   c  to gather or capture tissue therebetween and form a substantially U-shaped pleat in the captured tissue, as seen in  FIG. 9 . Simultaneously, boss  42  projects out of hole  36 . In other embodiments, for example, one having four fingers, the captured tissue would form a sideways S-shaped fold and one having five fingers, the captured tissue would form a W-shaped fold. 
         [0044]    Clip  28  may then be deployed to hold the captured tissue in the substantially U-shaped pleated gathered configuration. To deploy clip  28 , the user may actuate third button  66 . Upon actuation of third button  66 , shaft  48  moves toward fingers  26 . As shaft  48  moves forward, it urges clip  28  toward fingers  26 . 
         [0045]    With reference to  FIG. 11 , as clip  28  is being deployed, bases  52  of tines  32  contact boss  42  projecting out from hole  36 , causing tines  32  to move away from each other in the direction indicated by arrows C, as clip  28  is being urged distally by shaft  48 . With tines  32  in an expanded position, clip  28  captures tissue between the tines with each of the tines on the opposite sides of the tissue gathered in the U-shaped pleat. As clip  28  continues to move distally, boss  42  is positioned within recess  34  and bases  52  no longer contact the boss. As bases  52  of tines  32  are no longer subject to the forces exerted by boss  42 , the tines of clip  28  move toward each other and secure the captured tissue in the substantially U-shaped pleat or gathered configuration. Thus, the loose or floppy tissue in leaflet  2  is gathered and secured by clip  28 , thereby mitigating a cause of the prolapsed condition of the valve. 
         [0046]    Once clip  28  has secured the tissue of leaflet  2 , finger  26   b  is retracted from its deployed position to assume its retracted position. As finger  26   b  pivots upwardly from the retracted position, boss  42  is retracted into elongated member  16  through hole  36 . The retraction of boss  42  facilitates the proximal movement of elongated member  16  relative to clip  28 . Clip  28  is attached to the tissue captured therewithin. Grasping mechanism  22  is gradually withdrawn away from the captured tissue into outer tube  18 . As grasping mechanism  22  is gradually withdrawn, fingers  26  are urged toward their collapsed configuration by cylindrical base  30 , through which coupler  24  and fingers  26  are withdrawn. At the same time, outer tube  18  may be moved distally (i.e., away from handle  60 ) relative to elongated member  16  to its deployed position. As outer tube  18  moves to its deployed positions, it encloses elongated member  16  and fingers  26  in the collapsed condition. Catheter assembly  12  may then be completely withdrawn from clip  28 , leaving clip  28  secured to the tissue of valve  2 . 
         [0047]    Although the invention herein has been described with reference to particular embodiments, it is to be understood that these embodiments are merely illustrative of the principles and applications of the present invention. It is therefore to be understood that numerous modifications may be made to the illustrative embodiments and that other arrangements may be devised without departing from the spirit and scope of the present invention as defined by the appended claims. 
         [0048]    Although the disclosure herein has been described with reference to particular embodiments in which the catheter assembly is inserted into the patient via an introducer and through the apex of the heart (i.e., transapical insertion), it is to be understood that the disclosure contemplates embodiments in which the catheter assembly extends through a portion of the vasculature of the patient to reach the heart, for example, through a transfemoral or subclavian artery. In such embodiments, some of the device components may have to be oriented in a different direction to that described herein. For example, the disclosure contemplates embodiments in which the distal portion of the catheter assembly approaches the mitral valve from the upstream side as well as from the downstream side of the valve. 
         [0049]    It will be appreciated that the various dependent claims and the features set forth therein can be combined in different ways than presented in the initial claims. It will also be appreciated that the features described in connection with individual embodiments may be shared with others of the described embodiments.