Abstract:
A heart valve and tissue repair device for independently, selectively and sequentially grasping heart valve leaflets and independently, selectively and sequentially applying one or more fasteners thereto is disclosed. The device includes a leaflet engaging tip having one or more graspers capable of individually and sequentially grasping leaflets, and one or more deployable fasteners capable of fastening the leaflets. An actuation system for the device individually and selectively controls the graspers and deploys the one or more fasteners. Vacuum pressure from an external vacuum source can be used to grasp the leaflets via a selector system that controls the actuation system so as to individually and sequentially apply vacuum force to the graspers.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
       [0001]    The present application is a continuation of U.S. application Ser. No. 11/247,947, filed Oct. 11, 2005, under the same title, which is a continuation of U.S. application Ser. No. 10/106,583, filed Mar. 26, 2002, under the same title. This application discloses subject matter related to co-pending U.S. patent application Ser. No. 09/562,406, filed May 1, 2000, entitled “Minimally Invasive Mitral Valve Repair Method And Apparatus”, now U.S. Pat. No. 6,626,930, and co-pending U.S. patent application Ser. No. 09/778,392, filed Feb. 6, 2001, entitled “Method and System for Tissue Repair Using Dual Catheters. The entire disclosures of the aforementioned United States patent applications are incorporated herein by reference. 
     
    
     BACKGROUND OF THE INVENTION 
       [0002]    In vertebrate animals, the heart is a hollow muscular organ having four pumping chambers: the left atrium, the left ventricle, the right atrium and the right ventricle. The atria are isolated from their respective ventricles by one-way valves located at the respective atrial-ventricular junctions. These valves are identified as the mitral (or bicuspid) valve on the left side of the heart, and tricuspid valve on the right side of the heart. The exit valves from the left and right ventricles are identified as the aortic and pulmonary valves, respectively. 
         [0003]    The valves of the heart are positioned in valvular annuluses that comprise dense fibrous rings attached either directly or indirectly to the atrial and ventricular muscle fibers. Valve leaflets comprising flexible collagenous structures are attached to, and extend inwardly from, the annuluses to meet at coapting edges. The aortic, tricuspid and pulmonary valves each have three leaflets, while the mitral valve only has two. In normal operation, the leaflets of the mitral valve open as left ventricle dilates thereby permitting blood to flow from the left atrium into the left ventricle. The leaflets then coapt (i.e. close) during the contraction cycle of the left ventricle, thereby preventing the blood from returning to the left atrium and forcing the blood to exit the left ventricle through the aortic valve. Similarly, the tricuspid valve regulates flow from the right atrium into the right ventricle, and the pulmonary valve regulates blood exiting the right ventricle. 
         [0004]    For a number of clinical reasons various problems with heart valves can develop. One common form of heart disease involves the deterioration or degradation of the heart valves which leads to stenosis and/or insufficiency. Heart valve stenosis is a condition in which the valve does not open properly. Insufficiency is a condition in which the valve does not close properly. Insufficiency of the mitral valve, most common because of the relatively high fluid pressures in the left ventricle, results in mitral valve regurgitation (“MR”), a condition in which blood reverses its intended course and flows “backward” from the left ventricle to the left atrium during heart contractions. 
         [0005]    A number of surgical techniques have been developed to repair degraded or otherwise incompetent heart valves. A common procedure involves replacement of a native aortic or mitral valve with a prosthetic heart valves. These procedures require the surgeon to gain access to the heart through the patient&#39;s chest (or possibly percutaneously), surgically remove the incompetent native heart valve and associated tissue, remodel the surrounding valve annulus, and secure a replacement valve in the remodeled annulus. While such procedures can be very effective, there are significant shortcomings associated with such replacement valves. For example, the highly invasive nature of the implantation procedure typically results in substantial patient discomfort and requires patients to remain hospitalized for extended recovery periods. In addition, the two basic types of commercially available replacement valves, mechanical valves and tissue valves, each have shortcomings of their own. Mechanical replacement valves typically offer extended operational lifetimes, but the patient is usually required to maintain a regimen of anti-coagulant drugs for the remainder of his or her life. Tissue valves typically offer a higher degree of acceptance by the body which reduces or eliminates the need for anti-coagulants. However, the operational lifetimes of tissue valves are typically shorter than mechanical valves and thus may require a subsequent replacement(s) during the patient&#39;s lifetime. 
         [0006]    As an alternative to prosthetic heart valve replacement, it is often preferable to remodel the native heart valve and/or surrounding tissue. Remodeling of the valve often preserves left ventricular function better than mitral valve replacement because the subvalvular papillary muscles and chordae tendineae are preserved (most prosthetic valves do not require these muscles to operate). Typically, valvular remodeling is accomplished by implanting a prosthetic ring (a.k.a. “annuloplasty ring”) into the valve annulus to reduce and/or stabilize the structure of the annulus in order to correct valvular insufficiency. Annuloplasty rings are typically constructed of a resilient core covered with a fabric sewing material. Annuloplasty procedures can be performed alone, or they can be performed in conjunction with other procedures such as leaflet repair. Although such annuloplasty procedures have become popular and well accepted, reshaping the surrounding annulus and traditional leaflet repairs do not always lead to optimum leaflet coaptation. As a result, some patients may still experience residual mitral valve regurgitation following such annuloplasty procedures. 
         [0007]    A recently developed technique known as a “bow-tie” repair has also been advocated for repairing insufficient heart valves, in particular the mitral valve. The mitral valve bow-tie technique involves suturing the anterior and posterior leaflets together near the middle of their coapting edges, thereby causing blood to flow through two newly formed side openings. While this does reduce the volume of blood that can flow from the atrium to the ventricle, this is compensated by improved leaflet coaptation which reduces mitral regurgitation. This process as originally developed by Dr. Ottavio Alfieri involved arresting the heart and placing the patient on extracorporeal bypass and required invasive surgery to access and suture the leaflets together. More recently, however, some have advocated a “beating heart” procedure in which the heart is accessed remotely and remains active throughout the bow-tie procedure. 
         [0008]    A particular method for performing a beating heart bow-tie procedure (i.e. without extracorporeal bypass) has been proposed by Dr. Mehmet Oz, of Columbia University. A method and device for performing the method are described in PCT publication WO 99/00059, published Jan. 7, 1999. In one embodiment of the disclosed procedure, the associated device consists of a forceps-like grasper used to grasp and hold the mitral valve leaflets in a coapted position for the suturing step. Since the mitral valve leaflets meet and curve toward and slightly into the left ventricular cavity at their mating edges, the grasper device is passed through a sealed aperture in the apex of the left ventricle. The edges of the mating mitral valve leaflets are then grasped and held together, and a fastening device such as a clip or suture is utilized to fasten them. The fastening devices should be applied to the leaflet tissue with sufficient tissue purchase to prevent tearout or other failure, but close enough to the edges to ensure that the newly created side holes are as large as possible. The Mehmet Oz disclosure thus teaches that teeth of the grasper device can be linearly slidable with respect to one another so as to permit alignment of the mitral valve leaflets prior to fastening. Since the procedure is done on a beating heart, it will be readily understood that the pressures and motions within the left ventricle and mitral valve leaflets are severe. Thus the procedure taught by Dr. Mehmet Oz is very skill-intensive. 
         [0009]    The bow-tie technique has proved to be a viable alternative for treating otherwise incompetent heart valves. Nonetheless, several shortcomings associated with the current bow-tie procedures have been identified. Current systems include devices having mechanical graspers, barbed members, and vacuum devices that simultaneously capture and retain the valve leaflets prior to applying a fastening device thereto. Often, use of these devices results in the less than optimal leaflet stabilization and fastener placement. Many of these problems arise from the fact that the surgeon is required to capture, retain and fasten the leaflets in one relatively inflexible procedure. These difficulties are compounded when the leaflets are small or calcified making them difficult to pull together, and in beating heart procedures in which the leaflets are actively functioning throughout the surgery. In light of the foregoing, there is presently a need for improved systems for stabilizing multiple tissue heart valve leaflets and placing a fastening device therebetween. More specifically, there is a present need for an improved bow-tie procedure for repairing a patient&#39;s mitral valve. 
       SUMMARY OF THE INVENTION 
       [0010]    The present invention provides a device capable of effectively stabilizing at least one heart valve leaflets, or portions of a single leaflet, and applying a fastener thereto. Those skilled in the art will appreciate that the present invention enables a user to apply such a fastener in vivo to a remote location within the patient&#39;s heart. 
         [0011]    In one aspect, the repair device of the present invention comprises a leaflet engaging tip, a leaflet grasping mechanism positioned on the leaflet engaging tip, a deployable fastener positioned on the leaflet engaging tip, and an actuation system in communication with the grasping mechanism and the fastener. The actuation system has at least two actuation modes and is capable of independently and sequentially operating in each actuation mode. In the first actuation mode the actuation system is capable of causing the grasping mechanism to grasp a first leaflet, deploying a first fastening element into the first leaflet, and subsequently causing the grasping mechanism to release the first leaflet. In the second actuation mode the actuation system is capable of causing the grasping mechanism to grasp a second leaflet, deploying a second fastening element into the second leaflet, and subsequently causing the grasping mechanism to release the second leaflet. 
         [0012]    In another aspect, the present invention comprises multiple fasteners having multiple fastening elements and wherein the actuation system is capable of independently and sequentially deploying the multiple fastening elements into the leaflets. 
         [0013]    In another aspect, the present invention utilizes an external vacuum source to enable the grasping mechanism to grasp a leaflet by applying vacuum force thereto. In this aspect the grasping mechanism comprises a vacuum port, the actuation system is in fluid communication with both the vacuum port and the vacuum source, and the actuation system is capable of selectively restricting or transmitting vacuum force from the vacuum source to the vacuum port. 
         [0014]    In another aspect, the present invention comprises one or more vacuum ports, each having at least one vacuum vane capable of directing vacuum force through the vacuum port while supporting a leaflet attached thereto. 
         [0015]    In another aspect, the present invention includes one or more vacuum ports, each having a fastener catch capable of engaging and retaining the fastening elements. 
         [0016]    In another aspect, the present invention utilizes an external vacuum source to enable the grasping mechanism to independently and sequentially grasp leaflets by applying vacuum force to multiple vacuum ports. In this aspect the grasping mechanism comprises first and second vacuum ports, the actuation system is in fluid communication with the vacuum ports and the vacuum source. In a first actuation mode the actuation system is capable of selectively restricting or transmitting vacuum force from the vacuum source to the first vacuum port and, in a second actuation mode the actuation system is capable of selectively restricting or transmitting vacuum force from the vacuum source to the second vacuum port. 
         [0017]    In a related aspect, the present invention comprises a user-operable selector capable of being placed in a first position that places an actuation system in a first actuation mode and a second position that places the actuation system in the second actuation mode. 
         [0018]    In a related aspect, the present invention comprises a user-operable vacuum actuator having an open position in which vacuum force is transmitted from a vacuum source to a selected port and a closed position in which vacuum force is isolated from the ports. 
         [0019]    In another aspect, the present invention comprises at least one deployable fastener comprising a length of suture material and fastening elements comprising needles connected to opposite ends of the suture material. 
         [0020]    In another aspect, the present invention comprises an actuation system having a user-operable fastener actuator capable of individually and sequentially deploying fastening elements. 
         [0021]    In another aspect, the present invention comprises an actuation system coupled to a user-operable selector capable of being placed in multiple positions. In a first position the selector places the actuation system in a first actuation mode, and a second position the selector places the actuation system in a second actuation mode. 
         [0022]    In another aspect, the present invention comprises a selector and fastener actuator having a trigger mechanism coupled to a force transmitter. In this aspect, a selector selectively couples the force transmitter with a first or second fastening element. 
         [0023]    In another aspect, the present invention comprises at least one deployable fastener selected from the group consisting of needles, sutures, staples, buttons, tissue-graspers, tissue clasps, and barbs. 
         [0024]    In another aspect, the present invention comprises an elongated body in communication with a tissue engaging tip, a handle portion in communication with the elongated body, and a user-operable selector coupled to the handle and capable of being placed in multiple positions. Placing the selector in a first position places an actuation system in a first actuation mode; and, placing the selector in a second position places the actuation system in the second actuation mode. 
         [0025]    In a related aspect, the present invention comprises a rigid elongated body. 
         [0026]    In a related aspect, the present invention comprises a flexible elongated body. 
         [0027]    In a related aspect, the present invention comprises an elongated body having at least one conduit therein. 
         [0028]    In another aspect, the repair device of the present invention comprises a leaflet engaging tip, at least two leaflet grasping mechanisms positioned on the leaflet engaging tip, at least one deployable fastener having multiple fastening elements positioned on the leaflet engaging tip, and an actuation system in communication with the grasping mechanism and the fastener. The actuation system has at least two actuation modes and is capable of independently and sequentially operating in each actuation mode. In the first actuation mode the actuation system is capable of causing a first grasping mechanism to grasp a first leaflet, deploying a first fastening element into the first leaflet, and subsequently causing the first grasping mechanism to release the first leaflet. In the second actuation mode the actuation system is capable of causing a second grasping mechanism to grasp a second leaflet, deploying a second fastening element into the second leaflet, and subsequently causing the second grasping mechanism to release the second leaflet. 
         [0029]    In another aspect, the present invention utilizes an external vacuum source to enable multiple grasping mechanisms to grasp leaflets by applying vacuum force thereto. In this aspect each grasping mechanism comprises a vacuum port, the actuation system is in fluid communication with each vacuum port and the vacuum source, and the actuation system is capable of selectively restricting or transmitting vacuum force from the vacuum source to each vacuum port. 
         [0030]    In another aspect, the present invention discloses a method of repairing a heart valve having multiple leaflets. The method includes stabilizing a first leaflet with the repair device, deploying a first fastener element into the stabilized first leaflet, disengaging the first leaflet from the repair device while leaving the first fastener element deployed therein, stabilizing a second leaflet with the repair device, deploying a second fastener element into the second leaflet, disengaging the second leaflet from the repair device while leaving the second fastener element deployed therein, and joining the first and second leaflets by reducing the distance between the first and second fastener elements. Additional leaflet portions may also be attached in a similar manner. 
         [0031]    In another aspect, the present invention discloses a method of controllably and selectively stabilizing multiple heart valve leaflets with vacuum force. 
         [0032]    In another aspect, the present invention discloses a method of stabilizing multiple heart valve leaflets with a piece of suture material by first fastening the suture material to the leaflets and then tying the suture material into a knot. 
         [0033]    In another aspect, the present invention comprises a method of adjusting the position of a repair device relative to a heart valve by monitoring fluid pressure around a distal end of the repair device. 
         [0034]    In another aspect, the present invention comprises a method of adjusting the position of a repair device relative to an atrial-ventricular junction by observing pressure differentials between blood in an adjacent ventricle and an adjacent atrium. 
         [0035]    Other objects, features, and advantages of the present invention will become apparent from a consideration of the following detailed description. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0036]    The apparatus of the present invention will be explained in more detail by way of the accompanying drawings, wherein: 
           [0037]      FIG. 1  shows a perspective view of the repair device of the present invention; 
           [0038]      FIG. 2  shows a perspective view of handle portion of the repair device of the present invention; 
           [0039]      FIG. 3  shows a perspective cross-sectional view of the internal components located within the handle portion of the repair device of the present invention; 
           [0040]      FIG. 4  shows a perspective view of the vacuum system of the repair device of the present invention; 
           [0041]      FIG. 5  shows a perspective view of the trigger assembly of the repair device of the present invention prior to actuation; 
           [0042]      FIG. 6  shows a perspective view of the trigger assembly of the repair device of the present invention during actuation; 
           [0043]      FIG. 7  shows a perspective view of the vacuum actuation assembly of the repair device of the present invention; 
           [0044]      FIG. 8  shows a perspective view of the vacuum actuation assembly of the repair device of the present invention positioned within the handle portion; 
           [0045]      FIG. 9  shows a side view of the vacuum actuation assembly of the repair device of the present invention positioned within the handle portion; 
           [0046]      FIG. 10  shows a perspective view of the exterior of the elongated body and tissue engaging tip of the repair device of the present invention; 
           [0047]      FIG. 11  shows a perspective view of the internal components of the elongated body of the repair device of the present invention; and 
           [0048]      FIG. 12  shows a perspective view of the internal components of the engaging tip of the repair device of the present invention. 
       
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0049]    Disclosed herein is a description of various illustrated embodiments of the present invention. This description is not to be taken in a limiting sense, but is made merely for the purpose of illustrating the general principles of the invention. The section titles and overall organization of the present description are for the purpose of convenience only and do not limit the present invention. 
         [0050]    The methods and devices of the present invention were primarily designed for use in the surgical treatment of heart valves. As those skilled in the art will appreciate, the exemplary sequential repair device disclosed herein is designed to minimize trauma to the patient before, during, and subsequent to a surgical procedure, while providing improved heart valve leaflet stabilization and enhanced placement of a fastening device thereon. The repair device of the present invention is particularly useful in repairing dysfunctional mitral valves by stabilizing the discrete valvular tissue pieces of the anterior and posterior leaflets and deploying a fastening device(s) thereto. 
         [0051]      FIG. 1  shows the sequential repair device of the present invention. As illustrated, the repair device  10  comprises a handle portion  12  in communication with an elongated body  14 . A leaflet engaging tip  16  is positioned on the distal portion of the elongated body  14 . Those skilled in the art will appreciate that the present invention may be manufactured from a plurality of materials including, without limitation, various metals, plastics, thermoplastics, silicones, elastomers, ceramics, composite materials, or various combinations of the aforementioned materials. For example, the handle portion  12  may be manufactured from acrylic, while the elongated body  14  may be manufactured from stainless steel. 
         [0052]      FIG. 2  shows a perspective view of the handle portion  12 . As shown in  FIG. 2 , the handle portion  12  comprises a grip portion  18  in communication with a housing body  20 . The grip portion  18  includes a trigger recess  22  capable of receiving a trigger  24  therein. A trigger guide  26  is positioned proximate to the trigger recess  22 . In addition to supporting the trigger  24 , the trigger guide  26  isolates the trigger  24  from the grip portion  18  thereby preventing the accidental actuation of the trigger  24 . In one embodiment, the grip portion  18  is perpendicularly attached to the housing body  20 , thereby forming a pistol-type grip. Those skilled in the art will appreciate that the handle portion  14  of the present invention may be manufactured in a plurality of shapes as desired by the operator. At least one external conduit recess  28  capable of receiving at least one external conduit  30  therein may be formed on the repair device  10 . 
         [0053]    The handle portion  12  further comprises a vacuum actuator recess  32  capable of receiving a vacuum actuator  34  and a vacuum selector  36  therein. As shown in  FIG. 2 , the vacuum actuator recess  32  may be positioned adjacent to the trigger recess  22  thereby permitting the user to single-handedly operate the vacuum actuator  34 , the vacuum selector  36 , and the trigger  24  simultaneously. In an alternate embodiment, the vacuum actuator recess  32  may be positioned remotely from the trigger recess  22  to prevent the accidental actuation of the vacuum actuator  34  or the vacuum selector  36 . 
         [0054]    An elongated body aperture  38  capable of receiving the elongated body  14  therein is formed in the housing body  20 . At least one coupling member receiver  40  capable of receiving at least one coupling member  42  therein is formed in the housing body  20  proximate to the elongated body aperture  38  to effect coupling of the elongated body  14  to the handle portion  12 . Those skilled in the art will appreciate that the at least one coupling member  42  may include, without limitation, screws, rivets, pins, or locking members, thereby permitting the elongated body  14  to be detachable from the handle portion  12 . In another embodiment, the elongated body  14  may be permanently attached to handle portion  12  with in a plurality of ways, such as welding or gluing. 
         [0055]      FIGS. 3 and 7  show the internal components in more detail. As shown in  FIG. 3  the handle portion may be split into two hollow halves comprising a first handle portion  12 A and a second handle portion  12 B which cooperatively form a handle cavity  44  and a housing cavity  46  within the handle portion  12 . At least one assembly device receiver  48  capable of receiving at least one assembly device (not shown) therein may be formed, e.g. molded, in the first and/or second handle portions  12 A,  12 B. Exemplary assembly devices include, but are not limited to, screws, rivets, assembly pins or adhesives. 
         [0056]      FIGS. 3 and 4  show vacuum system  50 . An external vacuum conduit  52 , positioned within the at least one external conduit recess  28  formed in the repair device  10 , is attached to a compressible main vacuum line  54  through a vacuum coupler  56 . The external vacuum conduit  52  is in communication with a vacuum source (not shown), thereby providing suction (i.e. vacuum pressure) to the repair device  10 . In addition, an external positioning conduit  58  is positioned within the at least one external conduit recess  28  and is attached to an internal positioning line  60  through a positioning coupler  62 . The external positioning conduit  58  may be in communication with a positioning system. In one embodiment, the external positioning conduit  58  may be in communication with a pressure sensing device. Those skilled in the art will appreciate that a pressure sensing device can be used to assist the user in the precise placement of the repair device  10  within the patient based on a determination of pressure levels within the various parts of the body. For example, such a pressure sensing system would assist the user in determining the position of the leaflet engaging tip  16  of the repair device  10  relative to the atrial-ventricular junction of the patient&#39;s heart by sensing variations in the internal pressure between the atrium and the ventricle. In other embodiments, the present invention may be easily adapted to utilize a plurality of alternate positioning systems, including, without limitation, optical systems, ultrasonic systems, echogenic systems, microwave positioning systems, radio-frequency positioning systems, or radio-opaque positioning devices. 
         [0057]    As shown in  FIGS. 3 and 4 , the main vacuum line  54  is attached to a vacuum manifold  64  through a vacuum coupler  66 . The internal positioning line  60  is similarly attached to the vacuum manifold  64  through a positioning line coupler  68 . The vacuum manifold  64  includes a first vacuum conduit coupler  70  capable of coupling to a first vacuum conduit  72  and a second vacuum conduit coupler  74  capable of coupling to a second vacuum conduit  76  thereby permitting the first and second vacuum conduits  72 ,  76  to communicate with the main vacuum line  54 . A positioning conduit  78  is attached to the vacuum manifold  64  through a positioning coupler  80 , thereby permitting the positioning conduit  78  to communicate with the internal positioning line  60 . The first vacuum conduit  72  attaches to the first elongated body vacuum conduit  82  through a coupling member  84 . Similarly, the second vacuum conduit  76  is attached to a second elongated body vacuum conduit  86  through a coupling member  88 . 
         [0058]      FIGS. 3 ,  5 , and  6  show the various components comprising trigger assembly  90 . The trigger assembly  90  includes a trigger rod  92  which in communication with the trigger  24  and includes a bias member  94 , illustrated as a spring, positioned thereon. A trigger safety  96  is positioned proximate to the trigger  24  and comprises a safety body  98  having a safety actuator  100  located thereon and a trigger catch  102  capable of engaging the trigger  24 . The trigger safety  96  is coupled to the repair device  10  with an attachment member  104 . An actuation tray  106  having an attachment unit  108  is attached thereto is in communication with the trigger  24 .  FIG. 6  shows the trigger assembly  90  during actuation. As shown, during actuation the trigger safety  96  is forced to deflect downwardly by the vacuum actuator (not shown in this figure), thereby causing the trigger catch  102  to disengage the trigger  24 . The trigger safety  96  enters the internal cavity  110  formed in the trigger  24  thereby, permitting the user to actuate the trigger  24  rearwardly, which results in compression of the bias member  94 . Once the actuation pressure on the trigger has been released, the bias member biases the trigger  24  to a non-actuated position, thereby permitting the trigger catch  102  to re-engage the trigger  24 . Those skilled in the art will appreciate the trigger safety  90  may be manufactured from a plurality of materials having sufficient resiliency to permit the repeated deflection thereof without a substantial loss of resiliency. 
         [0059]      FIGS. 3 ,  7 , and  8  show the various components comprising vacuum actuator assembly  112 . As shown, the vacuum actuator assembly  112  includes a vacuum actuator  34  and a vacuum selector  36  positioned on or proximate to a vacuum actuator  34 . For example, a vacuum selector port  114  capable of receiving the vacuum selector  36  therein may be formed in the vacuum actuator  34 . The vacuum selector  36 , which is capable of a first position and a second position, is in communication with a vacuum selector shaft  115  which includes a selector pivot  116 , which attaches the vacuum selector shaft to the housing body  20 , and an attachment orifice  118  located near the distal end thereof. Compression member  120  capable of engaging and compressing the main vacuum line  54  is in communication with the vacuum actuator  34 . Vacuum bias member  122  biases the vacuum actuator  34  outwardly. Ideally, the bias member  122  applies sufficient outward force to the vacuum actuator  34  to enable the compression member  120  to compressively squeeze the main vacuum line  54  against a stop, in this case the housing  12 , to seal the main vacuum line. Those skilled in the art will appreciate that the application of inward force by the user to the vacuum actuator  34  results in the compression of the vacuum bias member  122  and causes the compression member  120  to move inwardly thereby disengaging and unsealing the main vacuum line  54 . As the inward movement of the vacuum actuator  34  continues the compression member  120  engages the safety actuator  100  located on the trigger safety body  98 , thereby causing the trigger safety  96  to deflect downwardly which in turn permits full actuation of the trigger  24 . Thus, according to the illustrated embodiment, the trigger  24  may be actuated only when the vacuum actuator  34  is actuated. 
         [0060]      FIGS. 3 ,  8 , and  9  show the components of the force transmission system  124 . The force transmission system  124  comprises a selector toggle  126  which is attached to or otherwise in communication with the attachment orifice  118  located on the vacuum selector shaft  114 . The selector toggle  126  further includes a biasing member  128  positioned thereon, and a pivoting attachment member  130  to pivotally couple the selector toggle to the housing body  20 . The force transmission system  124  further comprises a transmission bridge  132  which is in communication with the selector toggle  126 . A first connecting rod  134  is attached to the transmission bridge  132  with a pivot pin  136 . Similarly, a second connecting rod  138  is attached to the transmission bridge  132  with a pivot pin  140 . The first and second connecting rods  134 ,  138  are connected to a first and second connecting rod mount  144 ,  150  located on a rocker bridge  142 . The rocker bridge  142  is in communication with a first and second pivoting actuation member catches  146 ,  152 , which are attached to the attachment unit  108  of the trigger actuation tray  106  with pins  148 ,  154 . At least one actuation member is capable of engaging the first and second pivoting catches  146 ,  152 . As shown in the present embodiment, first and second actuation members or rods  156 ,  158  each include at least one actuation flange  160  positioned thereon thereby forming a first capture region  162  on the first actuation member  156  and a second capture region  164  on the second actuation member  158  which are located proximate to the first and second actuation member catches  146 ,  152 . The distal portion of the each actuation member  156 ,  158  is in communication with the leaflet engaging tip  16  through the elongated body  14 . The proximal portion of the first and second actuation members  156 ,  158  includes a biasing members  166 ,  168 , respectively. A support member  65 , positioned on the vacuum manifold  64  supports the bias members  166 ,  168  and receives the actuation members  156 ,  158  during actuation. 
         [0061]      FIG. 10  shows the external components of the elongated body  14  and the leaflet engaging tip  16 . The elongated body  14  may be manufactured from a plurality of materials in various widths and length. Those skilled in the art will appreciate that the elongated body  14  can comprise a rigid body or, in the alternative, may be manufactured from a flexible material thereby enabling the repair device  10  to be delivered through a catheter to a repair site in vivo. As shown in  FIG. 10 , the outer surface of the elongated body  14  comprises an outer sheath  170  capable of coupling to the handle portion  12 . A guidewire retainer (not shown) may be included on the exterior surface of the outer sheath  170 , the guidewire retainer (not shown) capable of engaging a guidewire (not shown) for catheter based surgical procedures. A tip retainer  172  is located on the distal portion of the outer sheath  170  of the elongated body  14 . The tip retainer  172  is adapted to engage and retain the attachment device  174  of the tip engaging tip  16 . Those skilled in the art will appreciate that the tip retainer  172  may include screw receivers, ports, snap fit members, or threads adapted to receive the leaflet engaging tip  16 . 
         [0062]    As shown in  FIG. 10 , the external components of the leaflet engaging tip  16  include a proximal portion  178  and a distal portion  180 . A first and second engaging channel  182 ,  184  separate the proximal portion  178  from the distal portion  180 . The proximal portion  178  includes a first port or vacuum recess  186  located within the first engaging channel  182 . Similarly, a second port or vacuum recess  188  is located within the second engaging channel  184 . The proximal portion  178  also includes a mounting member  190  capable of being sealably received within the elongated body  14 , thereby effectively coupling the leaflet engaging tip  16  to the elongated body  14 . The attachment device  174  may be located on or otherwise in communication with the mounting member  190  to effectuate the coupling process. Those skilled in the art will appreciate that the leaflet engaging tip  16  of the present invention may be attached to the elongated body  14  in a plurality of ways including, without limitation, detachably coupled or permanently attached. 
         [0063]    The distal portion  180  of the leaflet engaging tip  16  includes a first and second actuation ports  194 ,  196  located within the first and second engaging channel  182 ,  184 . The actuation ports  194 ,  196  located on the distal portion  180  are capable of passing at least one fastening device (not shown in  FIG. 11 ) therethrough. 
         [0064]      FIG. 11  shows the internal components of the elongated body  14 . As shown in  FIG. 11 , a first and second elongated body vacuum conduits  82 ,  86 , respectively, and a first and second actuation members  156 ,  158  are located within an inner lumen  176  formed by the outer sheath  170 . The first and second elongated body vacuum conduits  82 ,  86  are in fluid communication with the first and second vacuum conduits  72 ,  76  located within the housing body  20  of the handle portion  12 . Similarly, the first and second actuation members  156 ,  158  are in communication with the force transmission system  124  positioned within the housing body  20  of the handle portion  12 . The positioning conduit  78  may be positioned within the elongated body inner lumen  176 . 
         [0065]      FIG. 12  shows the internal components of the leaflet engaging tip  16  of the present invention. A first vacuum recess device  198 , which is located within the first vacuum recess  186 , includes a vane member  200  capable of directing suction force through the first vacuum recess  186 . At least one first fastener catch  202  is formed on or otherwise in communication with the first vacuum recess device  198 . The at least one first fastener catch  202  is capable of receiving and retaining therein at least fastener device (described in more detail below). Similarly, the second vacuum recess device  204 , which is located within the second vacuum recess  188 , includes a vane member  206  capable of directing suction force through the second vacuum recess  188 . At least one second fastener catch  208  is formed on or otherwise in communication with the second vacuum recess device  204 . The at least one second fastener catch  208  is capable of receiving and retaining at least fastener device therein. 
         [0066]    First and second vacuum ports  210 ,  212  ( 210  not visible) are located within the first and second vacuum recesses  186 ,  188 . The first vacuum port  210  is in fluid communication with the first elongated body vacuum conduit  82 , while the second vacuum port  212  is in fluid communication with the second elongated body vacuum conduit  86 . A positioning port  213  in fluid communication with the positioning conduit  78  may be positioned on the proximal portion  178  or on the distal portion  180  of the engaging tip  16 . 
         [0067]    As shown in  FIG. 12 , the distal portion  180  of the leaflet engaging tip  16  communicates with the proximal portion  178  thereof through the first and second actuation members  156 ,  158 . The first actuation device  214  is in communication with the first actuation member  156 , while the second actuation device is in communication with the second actuation member  158 . The first actuation device  214  comprises at least one fastener device  218  positioned thereon. The at least one fastener device  218  is capable of engaging the at least one first catch  202  located within the first vacuum recess  186 . Similarly, the second actuation device  216  comprises at least one fastener device  220  positioned thereon. The at least one fastener device  220  is capable of engaging the at least one second catch  208  located within the second vacuum recess  188 . The illustrated embodiment shows each actuation device  214 ,  216 , respectively, having two fastener devices  218 ,  220 , respectively, mounted thereon. Those skilled in the art will appreciate that the present invention may be manufactured with a one or more fastener devices located on the actuation devices  214 ,  216 . The fastener devices  218 ,  220  may be attached to suture material (not shown) positioned within the actuation devices  214 ,  216 . It will be appreciated that the actuation devices  214 ,  216  of the present invention may be actuated independently. In addition, the illustrated embodiment includes needles and suture material as tissue fasteners, but those skilled in the art will appreciate that the invention may be easily adapted to apply a plurality of fasteners. Exemplary fasteners include staples, graspers, buttons, and toggles. 
         [0068]    Also disclosed herein is a method of using the sequential repair device of the present invention to repair discreet heart valve leaflets in vivo. While those skilled in the art will appreciate that the present invention may be adapted for use in many procedures throughout a patient&#39;s body, the inventive repair device  10  is particularly well suited for procedures to repair dysfunctional heart valves without requiring the patient&#39;s heart to be arrested. Following is a description of the inventive method for such a repair of a dysfunctional heart valve. 
         [0069]    To use the present invention, the external vacuum conduit  52  and external positioning conduit  58  are connected to an external vacuum source (not shown) and a selected positioning device. Thereafter, the operator gains access to the repair site in vivo. For example, in procedures involving the heart, one approach to the heart requires the patient be positioned for a left anterolateral thoracotomy. An incision is made in the patient&#39;s chest and the chest is entered through the bed of the fifth rib. The pericardium is incised posterior and parallel to the left phrenic nerve, such that the incision extends from the left pulmonary artery to the apex of the left ventricle. Thereafter, a sealing cannula may be positioned on the exterior atrial wall of the patient&#39;s heart. An exemplary sealing cannula is described in U.S. patent application Ser. No. 09/800,390, entitled “Sealing Access Cannula System”, filed on Mar. 5, 2001, which is incorporated herein by reference. An incision is made in the atrial tissue once the sealing cannula is sufficiently anchored to the heart wall. The leaflet engaging tip  16  of the present invention then inserted into the sealing cannula and advanced to a position proximate the mitral valve. 
         [0070]    One embodiment of the present invention includes a pressure transducer as a positioning device. The surgeon may determine the position of the leaflet engaging tip  16  with respect to the mitral valve based on various pressure readings from the pressure transducer. For example, the operator may determine the position of the leaflet engaging tip  16  with respect to the mitral valve by observing the pressure differential between the atrium and the ventricle, as ventricular pressure within the heart is considerably greater than the pressure within the atrium. 
         [0071]    Once the leaflet engaging tip  16  is positioned between the valve leaflets at the arterial-ventricular junction, the surgeon selects an actuation mode for the actuation system. In each successive actuation mode another leaflet, or portion of a leaflet, is to be grasped and a fastener attached thereto. The surgeon actuates the vacuum selector  36  to selectively apply a vacuum force to either the first or second vacuum recess  186 ,  188  located proximate to the first or second engaging channel  182 ,  184  (the actuated side will depend on which side the vacuum selector  36  is on). To apply suction to the first vacuum recess  186  the user positions the vacuum selector  36  to the first position, thereby causing the first pivoting catch  146  of the force transmission system  124  to engage the first capture region  162  located on the first actuation member  156 . Simultaneously, the second connecting rod  138  compressively engages the second vacuum conduit  76  thereby preventing vacuum flow therethrough. Thereafter, the user depresses the vacuum actuator  34  causing the compression member  120  of the vacuum actuation assembly  112  to disengage the compressible main vacuum line  54 , and permitting a vacuum flow through the first vacuum recess  186  which is in communication with the vacuum main line  54  through the first vacuum conduit  72 . The valve leaflet, which is located near the first vacuum recess  186 , is then captured by the vacuum force applied thereto. Once the leaflet has been captured, the user actuates the trigger assembly  90  of the repair device  10 . By actuating the trigger  24 , the user causes the first pivoting catch  146 , which is in communication with the actuation tray  106  of the trigger assembly  90 , to retract the first actuation member  156 , thereby causing the first actuation device  214  of the leaflet engaging tip  16  to retract. Continued actuation of the trigger  24  causes continued rearward movement of the first actuation device  214 , which results in the first fastener device  218  engaging and traversing the captured valve leaflet. Thereafter, the first fastener device(s)  218  engages a fastener catch  202  located within the first vacuum recess  186  and is retained therein. The user then releases the trigger  24 , which causes the first actuation device  214  to return to the extended position. Releasing the vacuum actuator  34  halts the application of vacuum force through the first vacuum recess  186  and releases the captured valve leaflet. The suture material remains positioned through the valve leaflet where the fastener device(s)  218  had traveled therethrough. 
         [0072]    The user may then capture another portion of the same valve leaflet, or another leaflet, by changing the actuation system to another actuation mode. To capture another leaflet the user moves the vacuum selector  36  from the first position to the second position which causes the first pivoting catch  146  to disengage the first actuation member  156  and causes the second pivoting catch  152  of the force transmission system  124  to engage the second capture region  164  located on the second actuation member  158 . Simultaneously, the first connecting rod  134  compressively engages the first vacuum conduit  72  thereby preventing vacuum flow therethrough while the second connecting rod  138  disengages the second vacuum conduit  76  thereby permitting a vacuum flow therethrough. Thereafter, the user depresses the vacuum actuator  34  causing the compression member  120  of the vacuum actuation assembly  112  to disengage the compressible main vacuum line  54 , and permits a vacuum flow through the second vacuum recess  188  which is in communication with the vacuum main line  54  through the second vacuum conduit  76 . The valve leaflet located near the second vacuum recess  188  is then captured by the vacuum force applied thereto. Once the leaflet has been captured, the user actuates the trigger assembly  90  of the repair device. By actuating the trigger  24  the user causes the second pivoting catch  152 , which is in communication with the actuation tray  106  of the trigger assembly  90 , to retract the second actuation member  158  thereby causing the second actuation device  216  of the leaflet engaging tip  16  to similarly retract. Continued actuation of the trigger  24  causes continued rearward movement of the second actuation device  216  which results in the second fastener device(s)  220  engaging and traversing the captured leaflet. Thereafter, the second fastener device(s)  220  engages a second fastener catch  208  located within the second vacuum recess  188  and is retained therein. The user can then release the trigger  24  thereby returning the second actuation device  216  to an extended position. Release of the vacuum actuator  34  halts the application of vacuum force and releases the valve leaflet. The suture material remains positioned through the valve leaflet where the fastener device(s)  220  had traveled therethrough. 
         [0073]    The user can remove the repair device  10  from the patient&#39;s heart. The suture material, which has been positioned through various portions of the valve tissue remains in place while the extraneous suture material is feed from the repair device  10  during removal. Thereafter, a surgical knot may be formed in the extraneous suture material and advanced to an area within the heart using a surgical knot pusher, thereby approximating the valve leaflet tissue. Once the final knot is applied to the area of interest the extraneous suture material is trimmed and the various incisions are closed. 
         [0074]    In closing, it is noted that specific illustrative embodiments of the invention have been disclosed hereinabove. It is to be understood that the invention is not limited to these specific embodiments. This specification has focused on the application of the present inventive devices and methods to the repair of heart valve leaflets. However, one of skill in the art will appreciate that the disclosed devices and methods could alternatively be used to approximate any two pieces of tissue throughout a patient&#39;s body. For example, the present invention may also used to repair Arterial Septal Defects (ASD), Ventricular Septal Defects (VSD), and defects associated with Patent Foramen Ovale (PFO). Accordingly, it should be recognized that the references to “leaflets” throughout could be equally substituted for other tissue segments that might require similar approximation procedures. 
         [0075]    With respect to the claims, it is applicant&#39;s intention that the claims not be interpreted in accordance with the sixth paragraph of 35 U.S.C. §112 unless the term “means” is used followed by a functional statement. Further, with respect to the claims, it should be understood that any of the claims described below can be combined for the purposes of the invention.