Patent Publication Number: US-2011066234-A1

Title: Percutaneous Mitral Valve Annuloplasty Delivery System

Description:
CROSS-REFERENCE 
     This application is a continuation of U.S. patent application Ser. No. 10/946,332, filed Sep. 20, 2004, now U.S. Pat. No. 7,837,729, which is a continuation-in-part of U.S. patent application Ser. No. 10/313,914, filed Dec. 5, 2002, now U.S. Pat. No. 7,316,708, and of U.S. patent application Ser. No. 10/331,143, filed Dec. 26, 2002, now U.S. Pat. No. 6,793,673; which applications are incorporated herein by reference in their entirety and to which applications we claim priority under 35 USC §120. 
    
    
     BACKGROUND OF THE INVENTION 
     The invention relates generally to percutaneous delivery systems for tissue shaping devices intended to be delivered through a lumen to a site within a vessel of the patient to modify target tissue adjacent to the vessel. In particular, the invention relates to delivery systems for percutaneous mitral valve annuloplasty devices and methods for using the same. 
     Tissue shaping devices for treating mitral valve regurgitation have been described. See, e.g., U.S. patent application Ser. No. 10/142,637 (now U.S. Pat. No. 6,824,562), “Body Lumen Device Anchor, Device and Assembly;” U.S. patent application Ser. No. 10/331,143 (now U.S. Pat. No. 6,793,673), “System and Method to Effect the Mitral Valve Annulus of a Heart;” U.S. patent application Ser. No. 10/429,172, “Device and Method for Modifying the Shape of a Body Organ;” and U.S. patent application Ser. No. 10/742,516, “Tissue Shaping Device With Conformable Anchors.” These devices are intended to be delivered percutaneously to a site within a patient&#39;s coronary sinus and deployed to reshape the mitral valve annulus adjacent to the coronary sinus. 
     During deployment of such tissue shaping devices one or more anchors may need to be expanded and locked using actuation forces delivered from outside the patient. Thus, the percutaneous delivery and deployment of tissue shaping devices may require the physician to perform remote operations on the device and on the patient through the device. What is needed, therefore, is a delivery system that permits the physician to perform these tasks. 
     SUMMARY OF THE INVENTION 
     The present invention provides a tissue shaping delivery system and method. One aspect of the invention is a tissue shaping system including a tissue shaping device with an expandable anchor and a lock; a delivery catheter; a delivery mechanism (including, e.g., a pusher) adapted to deliver the tissue shaping device from outside a patient to a target site within a lumen within the patient via the delivery catheter; and an actuator adapted to deliver an actuation force to the lock to lock the anchor in an expanded configuration. In some embodiments, the invention includes a cartridge adapted to contain the tissue shaping device, the delivery mechanism being further adapted to deliver the tissue shaping device from the cartridge to the delivery catheter. The tissue shaping system may also include a dye port adapted to admit an imaging contrast agent to the lumen, such as during delivery and deployment of the tissue shaping device. The dye port may be part of a connector extending from a proximal end of the delivery catheter, with the connector also, including a device port, the delivery mechanism being further adapted to delivery the tissue shaping device from outside the patient to the delivery catheter through the device port. 
     In some embodiments the tissue shaping system includes a handle associated with the delivery mechanism. The handle may be adapted to support the actuator. In embodiments in which the system includes a cartridge adapted to contain the tissue shaping device, the cartridge may be further adapted to engage the handle during delivery and/or deployment of the tissue shaping device. 
     In some embodiments of the tissue shaping system, the actuator is further adapted to operate the delivery mechanism to move the tissue shaping device with respect to the delivery catheter to, e.g., expose or recapture the anchor. In some embodiments, the actuator is a rotating nut. 
     In some embodiments of this aspect of the invention the actuator is adapted to move the delivery catheter distally to lock the anchor. In other embodiments the tissue shaping system may also include a locking sleeve, the actuator being further adapted to move the locking sleeve distally to lock the anchor. 
     In some embodiments the tissue shaping system includes an attachment mechanism adapted to attach the tissue shaping device to the delivery mechanism, such as a tether attached to the tissue shaping device. The attachment mechanism may be further adapted to release the tissue shaping device from the delivery mechanism, such as through the use of a hitch wire and a tether attached to the tissue shaping device. The attachment mechanism may also include a hitch wire actuator adapted to move the hitch wire to release the tether from the device and/or a device release interlock adapted to prevent release of the device prior to actuating the anchor lock actuator. 
     In some embodiments of the tissue shaping system, the tissue shaping device further includes a second anchor, the actuator being further adapted to deliver an actuation force to a second anchor lock to lock the second anchor in an expanded configuration. The system may alternatively have a second actuator, the second actuator being further adapted to deliver an actuation force to the second anchor lock to lock the second anchor in an expanded configuration. A handle may support the first and second actuators. 
     Another aspect of the invention provides a system adapted to percutaneously deliver and deploy a tissue shaping device at a target site within a lumen of a patient, including: a handle; a delivery mechanism (possibly including a pusher) supported by the handle and adapted to deliver the tissue shaping device from outside the patient to the treatment site via a delivery catheter; and an actuator supported by the handle and adapted to deliver an actuation force to lock an anchor of the tissue shaping device in an expanded configuration. In some embodiments the handle has a cartridge interface adapted to mate with a cartridge containing a tissue shaping device, and the delivery system may be further adapted to deliver the tissue shaping device from a delivery catheter to the target site when a tissue shaping device cartridge engages the cartridge interface. In some embodiments, the actuator may include the cartridge interface. In some embodiments the actuator may include a rotating member with threads adapted to mate with threads on a cartridge. 
     In some embodiments the system includes a locking sleeve, the actuator being further adapted to move the locking sleeve distally to lock the anchor. The handle may include a channel, with the actuator being disposed in the channel, and the actuator may include an actuator lock adapted to prevent movement of the actuator within the channel. 
     In some embodiments the system includes a device attachment mechanism supported by the handle and adapted to attach the tissue shaping device to the handle. The attachment mechanism may include a tether attached to the handle and/or a hitch wire attached to the handle. In embodiments with a hitch wire the attachment mechanism further may a hitch wire actuator adapted to move the hitch wire to release the device and possibly a device release interlock adapted to prevent operation of the hitch wire actuator prior to actuating the anchor lock actuator. 
     INCORPORATION BY REFERENCE 
     All publications and patent applications mentioned in this specification are herein incorporated by reference to the same extent as if each individual publication or patent application was specifically and individually indicated to be incorporated by reference. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The novel features of the invention are set forth with particularity in the appended claims. A better understanding of the features and advantages of the present invention will be obtained by reference to the following detailed description that sets forth illustrative embodiments, in which the principles of the invention are utilized, and the accompanying drawings of which: 
         FIG. 1  is a cross-sectional view of a human heart showing a tissue shaping device in the lumen of the coronary sinus. 
         FIG. 2  is a schematic view of a tissue shaping device delivery system according to this invention. 
         FIG. 3  is a cross-sectional view showing a step in the delivery and deployment of a tissue shaping device according to this invention. 
         FIG. 4  is a cross-sectional view showing another step in the delivery and deployment of a tissue shaping device according to this invention. 
         FIG. 5  is a cross-sectional view showing another step in the delivery and deployment of a tissue shaping device according to this invention. 
         FIG. 6  is a cross-sectional view showing another step in the delivery and deployment of a tissue shaping device according to this invention. 
         FIG. 7  is a cross-sectional view showing a step in the recapture of a tissue shaping device according to this invention. 
         FIG. 8  is a cross-sectional view showing a step in the recapture of a tissue shaping device according to this invention. 
         FIG. 9  shows an attachment mechanism for a tissue shaping device delivery system. 
         FIG. 10  shows another attachment mechanism for a tissue shaping device delivery system. 
         FIG. 11  shows yet another attachment mechanism for a tissue shaping device delivery system. 
         FIG. 12  shows still another attachment mechanism for a tissue shaping device delivery system. 
         FIG. 13  is a detail of the attachment mechanism of  FIG. 12  in a disengaged configuration. 
         FIG. 14  is a perspective view of a tissue shaping device delivery system according to this invention. 
         FIG. 15  is another perspective view of the tissue shaping device delivery system of  FIG. 14  showing a tissue shaping device without a cartridge. 
         FIG. 16  is an exploded view of the tissue shaping device and delivery system of  FIG. 15 . 
         FIG. 17  is a partial cross-sectional view of certain portions of the tissue shaping device delivery system of  FIG. 15 . 
         FIG. 18  is a detailed cross-sectional view of a portion of the tissue shaping device shown in  FIG. 17 . 
         FIG. 19  is a perspective view of a cartridge for the tissue shaping device delivery system of  FIG. 14 . 
         FIG. 20  is a cross-sectional view of the cartridge of  FIG. 19 . 
         FIG. 21  is a cross-sectional view of a delivery catheter and connector for use with the tissue shaping device delivery system of  FIGS. 14-20 . 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     While the invention relates to methods and devices for delivering tissue shaping devices generally, the invention will be described with respect to tissue shaping devices delivered to the coronary sinus of the heart to reshape the mitral valve annulus to treat mitral valve regurgitation. As used herein, “coronary sinus” includes the great cardiac vein as well as the coronary sinus of the heart. 
       FIG. 1  shows a cross-section of a human heart  10  with the atria removed to show the mitral valve  12 , the mitral valve annulus  14  and the coronary sinus  16 . A tissue shaping device  20  in the form of a percutaneous mitral valve annuloplasty device is disposed within the coronary sinus to reshape the mitral valve annulus  14  to provide for improved coaptation of the mitral valve leaflets. As shown, tissue shaping device  20  has an expandable distal anchor  22 , a distal anchor lock  24 , an expandable proximal anchor  26 , a proximal anchor lock  28 , and a connector  30  extending between the distal and proximal anchors. Proximal anchor lock  28  has serves as a delivery system attachment mechanism, as explained below. 
       FIG. 2  is a schematic drawing showing the general elements of a delivery system  40  adapted to delivering and deploying a tissue shaping device to a target site within the lumen of a vessel in or around a patient&#39;s heart  42 . A delivery catheter  44  has been inserted through an opening  46  formed in the patient&#39;s jugular vein or other blood vessel and advanced into the heart. Delivery system  40  interacts with delivery catheter  44  to deliver and deploy the tissue shaping device at the target site within the patient. 
       FIGS. 3-6  show steps from the delivery and deployment of a tissue shaping device having at least one anchor similar to the anchors of device  20  of  FIG. 1 . In  FIG. 3 , a tissue shaping device  50  has been delivered to a target site within the lumen of a vessel  54  via a delivery catheter  56 .  FIG. 3  shows an expandable anchor  52  of tissue shaping device  50  beginning to emerge from catheter  56 . In this embodiment, this action is due to proximal movement of catheter  56  while device  50  is held stationary. In alternative embodiments, the device could be delivered from the distal end of the catheter by pushing the device distally while holding the catheter stationary or a combination of distal movement of the device and proximal movement of the catheter. Anchor  52  is shown in a collapsed, unexpanded configuration. 
     A delivery system  70  provides the mechanisms to deliver and deploy device  50  from outside the patient. Actuator  72  and delivery mechanism  74  associated with catheter  56  and device  50 , respectively, provide for the relative movement between device  50  and catheter  56 . For example, delivery mechanism  74  may be a pusher used to advance device  50  down catheter  56  to the target site shown in  FIG. 3 , and actuator  72  can be used to pull catheter  56  proximally while delivery mechanism  74  holds device  50  stationary within vessel  54 . Actuator  72  and delivery mechanism  74  may be supported by a handle or other housing  76 . 
     In  FIG. 4 , catheter  56  has been pulled further proximally by actuator  72  so that anchor  52  is completely outside of catheter  56  and has started to self-expand. In this embodiment, anchor  52  is formed from a shape memory material (such as Nitinol) and has been treated so as to expand upon emergence from the catheter. 
       FIGS. 5 and 6  show how the delivery system may be used to further expand and lock anchor  52 . Formed in the proximal side  58  of anchor  52  is a loop  60  encircling a proximally extending connector  62 . Connector  62  may connect with other elements at the proximal side of device  50 , such as a second anchor, depending on device design. As shown in  FIG. 5 , while delivery mechanism  74  holds device  50  stationary, actuator  72  has moved delivery catheter  56  distally to engage the proximal side  58  of anchor  52  and to move it distally to further expand anchor  52 . 
     As shown in  FIG. 6 , further distal movement of delivery catheter  56  with respect to device  50  has pushed loop  60  distally over a lock bump  64 . Lock bump  64  cams inward in response to the distal force of loop  60 , then returns to its prior shape to hold loop  60  distal to lock bump  64 . Delivery catheter may then be moved proximally to perform other functions or to be removed from the patient. 
     After deployment of a tissue shaping device, it may become necessary to reposition the device or to remove the device from the patient.  FIGS. 7 and 8  demonstrate the recapture of tissue shaping device  50  back into delivery catheter  56  after delivery and deployment. 
     In  FIG. 7 , delivery mechanism  74  holds device  50  stationary while delivery catheter  56  is advanced distally against anchor  52  by actuator  72 . The actuation force against anchor  52  collapses the anchor, allowing delivery catheter to recapture the device as shown in  FIG. 8 . The catheter and device can then be removed from the patient or moved to another target site. 
       FIG. 9  shows an attachment mechanism between a tissue shaping device  80  and a delivery mechanism, such as pusher  82 , within a delivery catheter  84 . Pusher extends outside of the patient and is attached to a handle or other housing  86 , such as through an actuator. Pusher  82  may be operated by an actuator or by the handle itself to advance device  80  distally through catheter  84  or to hold device  80  stationary against a proximal force exerted on device  80 , such as when delivery catheter  84  is withdrawn proximally by an actuator  88 . 
     Device  80  has an attachment eyelet  90 . A tether  92  extending down pusher  82  has a loop  94  formed at its distal end. The proximal ends of tether  92  are preferably attached to handle  86 . Loop  94  extends through eyelet  90 , and a hitch wire  96  passes through loop  94  and into the proximal end of device  80  as shown, thereby preventing loop  94  from being withdrawn from eyelet  90 . Tether  92  can be used to pull device  80  proximally or to hold device  80  stationary against a distal force exerted on device  80 , such as during recapture. Tether  92  may also be used to hold device  80  tightly against pusher  82  during delivery and deployment of the device. 
     To release device  80  from the delivery mechanism, hitch wire  96  may be disengaged from device  80 . In this embodiment, hitch wire  96  is disengaged by moving the hitch wire proximally through the action of a hitch wire actuator  98  while holding device  80  stationary with pusher  92 . When hitch wire  96  is disengaged from device  80  and moved proximal to the loop of tether  92 , proximal movement of tether  92  will pull the tether&#39;s loop out of eyelet  90 . 
       FIG. 10  shows another attachment mechanism for a tissue shaping device and its delivery mechanism. As in the embodiment of  FIG. 9 , an eyelet  102  extends proximally from tissue shaping device  100  within delivery catheter  104 . The distal end of pusher  106  has an eyelet  108  at its distal end that overlaps with device eyelet  102  to form an overlap opening  110 . A hitch wire  112  extends through pusher  106  and overlap opening  110  into the proximal end of tissue shaping device  100 . 
     As in the previous embodiment, catheter  104 , pusher  106  and hitch wire  112  extend out of the patient to a handle or other housing  114 . Pusher  106  may be operated by an actuator or by handle  114  to advance device  100  distally through catheter  104  or to hold device  100  stationary against a proximal force exerted on device  100 , such as when delivery catheter  104  is withdrawn proximally by an actuator  116  supported by handle  114 . Also, because the attachment mechanism of this embodiment holds pusher  106  against device  100 , pusher  106  can be used to pull device  100  proximally or to hold device  100  stationary against a distal force exerted on device  100 , such as during recapture. 
     To release device  100  from the delivery mechanism, hitch wire  112  may be disengaged from device  100 . As in the embodiment of  FIG. 9 , hitch wire  112  is disengaged by moving the hitch wire proximally through the action of a hitch wire actuator  118  while holding device  100  stationary with pusher  106 . When hitch wire  112  is disengaged from device  100  and moved proximal to the overlap opening  110 , device  100  is disengaged from the delivery mechanism. 
       FIG. 11  shows an attachment mechanism that can be used to engage a tissue shaping device after initial deployment for possible recapture of the device. As in other embodiments, device  120  has a proximal eyelet  122 . Retractor  124  has a cable  126  extending through it. Cable  126  has a loop  128  at its distal end and free ends  130  extending out of the patient, possibly to a handle or housing (not shown). To engage device  120 , retractor  124  and looped cable  126  are advanced to device  120  with loop  128  arranged to be large enough to surround eyelet  122 . When loop  128  passes over and around eyelet  122 , one or both of the free ends of cable  126  are pulled proximally to pull loop  128  tightly about eyelet  122 , as shown. Retractor  124  may then be used to pull device  120  proximally, such as for recapture into a catheter. Alternatively, retractor may be used as a pusher to apply a distally directed force on device  120 , if needed. 
       FIGS. 12 and 13  show yet another attachment mechanism between a tissue shaping device and a delivery mechanism. Tissue shaping device  140  has a locking structure  142  at its proximal end designed to mate with a corresponding locking structure  144  at the distal end of a pusher  146  within catheter  148 . A cover  150  is disposed over the interlocked locking structures to maintain the connection between device  140  and pusher  146 . A tether  152  is connected to cover  150 . 
     Catheter  148 , pusher  146  and tether  152  extend out of the patient to a handle or other housing  154 . Pusher  146  may be operated by an actuator or by handle  154  to advance device  140  distally through catheter  148  or to hold device  140  stationary against a proximal force exerted on device  140 , such as when delivery catheter  148  is withdrawn proximally by an actuator  156  supported by handle  154 . Also, because the attachment mechanism of this embodiment holds pusher  146  against device  140 , pusher  146  can be used to pull device  140  proximally or to hold device  140  stationary against a distal force exerted on device  140 , such as during recapture. 
     To release device  140  from the delivery mechanism, tether  152  may be pulled proximally to pull cover  150  off of the locking structures  142  and  144 , such as by use of an actuator  158 , while holding device  100  stationary with pusher  146 . Locking structures  142  and  144  are preferably formed from a shape memory material. When cover  150  is removed from the locking structures, the locking structures assume an unstressed configuration such as that shown in  FIG. 13 , thereby disengaging device  140  from pusher  146 . 
       FIGS. 14-21  show a tissue shaping device delivery and deployment system according to one embodiment of this invention. The system includes a handle  200  supporting delivery, deployment and attachment mechanisms for a tissue shaping device  202  having distal and proximal expandable anchors  204  and  206 , respectively. In  FIG. 14 , the device is disposed in a compressed configuration within a cartridge  208 . In this embodiment, the device will go directly from cartridge  208  into a delivery catheter for delivery and deployment in a patient. 
     As shown in  FIG. 15 , a pusher  210  abuts the proximal end of tissue shaping device  202 . Pusher  210  should be flexible and incompressible, and its properties may vary from section to section along its length. In one embodiment, pusher  210  is formed at its distal end from a coiled spring  212  (e.g., to facilitate bending) and thereafter from a stainless steel hypotube  214 . Device  202  is attached to pusher  210  via a tether  216  and hitch wire  218  in an arrangement such as that described above with respect to  FIG. 9 . The tether has to be strong enough to apply an appropriate proximally directed force during delivery, deployment and recapture; the hitch wire has to be stiff enough not to kink or pull through the eyelet when the tether is pulled proximally. For example, for use in a tissue shaping system intended to treat mitral valve regurgitation via the coronary sinus, the tether preferably can pull up to 18 pounds. In one embodiment, tether  216  is formed from 0.007 inch stainless steel with a full hard temper, and hitch wire is formed from 0.011 inch  304  stainless steel. Tether  216  and hitch wire  218  extend through the pusher&#39;s lumen. Pusher  210 , tether  216  and hitch wire  218  are attached to and supported by handle  200 , as discussed below with respect to  FIGS. 17 and 18 . 
     Surrounding pusher  210  is a locking sleeve  220  whose inner diameter is close to the outer diameter of pusher  210  in order to minimize backflow of blood or other fluids. The proximal end of locking sleeve  220  is supported by a slider (not shown) resting in a circular track formed by the handle housing. Actuator knobs  222  are threaded into holes formed in the sides of the slider, and the slider and actuator knobs are attached to the locking sleeve  220  by adhesive. One of the actuator knobs may be provided with an actuation interlock, such as a screw down portion  223  that screws against the handle housing to prevent movement of the actuator knobs and locking sleeve. As shown in  FIG. 16 , actuator knobs  222  fit in tracks  224  formed in handle  200 . 
     When assembling the delivery system, pusher  210  is placed within locking sleeve  220 . Handle housing  226  has two parts,  228  and  230 , which are placed and screwed together around the locking sleeve and pusher. As shown in  FIG. 18 , assembly of the two halves of handle housing  226  attaches the proximal end of pusher  210  to handle  200  with a press fit connection (which may be supplemented with adhesive) in a pusher connection area  232  of handle housing  226 . Locking sleeve actuator knobs  222  are in the tracks  224 , as discussed above. 
     Hitch wire  218  and tether  216  are then threaded into the central lumen of pusher  210 , and device  202  is attached by placing the looped end of tether  216  through an eyelet (not shown) on the proximal end of device  202 . Hitch wire  218  passes through the looped end of tether  216  into the device&#39;s proximal anchor crimp tube  207 . (Placement of the distal end of the hitch wire inside the crimp tube helps prevent injury to the patient&#39;s heart or blood vessels by the hitch wire.) 
     Tether  216  and hitch wire  218  extend proximally from the proximal end of pusher  210  through the proximal end of pusher connection area  232  and through holes formed in a disc  236  disposed proximal to pusher connection area  232  and jack nut  234 . A crimp tube  238  or other connector attaches to the proximal end of tether  216  to prevent it from passing distally through disc  236 ; excess portions of tether  216  may be cut off. A jack nut  234  threaded around the outside of pusher connection area  232  may then be rotated about pusher connection area  232  to move jack nut  234 , disc  236  and crimp tube  238  proximally with respect to the handle housing, thereby tightening tether  216  and pulling device  202  tight against pusher  210 . 
     A release knob  240  is threaded onto handle housing  226  around pusher connection area  232  with track portions  242  lining up with handle tracks  224 , as shown. Hitch wire  218  extends proximally through release knob  240  and a second disc  244 , and the proximal end of hitch wire  218  is crimped with one or more crimp tubes  246  to prevent distal movement of hitch wire  218  with respect to the handle. A cap  248  covers the distal end of hitch wire  218  to prevent injury to the user from the sharp wire end. 
     Prior to delivery and deployment, the eyelet of the proximal anchor  206  is pulled proximally over the pusher coil  212 , and the eyelet of the distal anchor is pulled proximally over the connector between the two anchors. Device  202  is then compressed and loaded into cartridge  208  with the distal anchor  204  at the distal end of the cartridge and with the pusher, tether and hitch wire extending from the proximal end of cartridge  208  into handle  200 . A loading tool, such as a two-piece funnel, may be used to assist in the compression and loading of the device into the cartridge. In a preferred embodiment, a control nut  250  is threaded onto the threaded exterior of cartridge  208 , as shown in  FIG. 14 . 
     Cartridge  208  is shown in more detail in  FIGS. 19 and 20 . Cartridge  208  has a central lumen  252  with a lubricious polymeric liner. The diameter of central lumen  252  may be substantially the same as the diameter of a delivery catheter to be used to deliver device  202 . Alternatively, the diameter of central lumen  252  may be larger than the intended delivery catheter diameter to minimize stress on the tissue shaping device during sterilization, temperature changes during shipping, etc. Cartridge  208  has a male luer connector  254  at its distal end for mating with a corresponding female luer connector on the delivery catheter, as described below. The outside of the cartridge preferably has at least one flat side in order to prevent rotation of the cartridge with respect to the handle during deployment, as described below. In the embodiment shown in  FIGS. 19 and 20 , cartridge  208  has a hexagonal cross-section presenting six possible orientations for mating with a flat side formed on the inside of the handle during delivery and deployment of the tissue shaping device. An O-ring seal  255  at the proximal end of cartridge  208  seals around locking sleeve  220  to prevent backflow of blood or other fluids while still permitting relative movement between locking sleeve  220  and cartridge  208 . 
       FIG. 21  shows a delivery catheter  260  and connector  262  for use with the cartridge and handle of this invention. The length and diameter of catheter  260  depends on the application. For example, to deliver a tissue shaping device to the coronary sinus through the jugular vein to treat mitral valve regurgitation, catheter  260  may be a nine french diameter catheter at least 65 cm. long. Catheter  260  may also have a radiopaque market on its distal end for visualization via fluoroscopy. When it needs to negotiate bends and turns to reach the target treatment site, catheter  260  may be more flexible at its distal tip than along its proximal end. Catheter  260  may also be braided to increase its compression strength, which aids in locking anchors, recapturing devices, etc., as described below. 
     Y-shaped connector  262  is attached to the proximal end of catheter  260  by adhesive and a shrink tube  264 . Connector  262  has a main channel  266  with a female luer connection  268  adapted to mate with the luer connection of cartridge  208 . A second channel  270  meets the main channel  266  proximal to the proximal end of delivery catheter  260 . Second channel  270  also has a luer connection to permit it to be connected to a source of imaging contrast agent, such as dye. Second channel  270  enables a dye source to be connected and for dye to be injected even during use of the main channel to deliver and deploy the tissue shaping device. (The space between the inner diameter of the delivery catheter and the outer diameter of the locking sleeve permits contrast dye to flow distally to the target treatment site.) A cap  272  may be used to close off second channel  270  when not in use. The diameters of both channels transition down from the standard luer fitting size to the diameter of the delivery catheter. 
     A first step for using the tissue shaping system of this invention to treat mitral valve regurgitation is to access the coronary sinus of the patient&#39;s heart. One way of reaching the coronary sinus is to insert a sheath into the patient&#39;s jugular vein. A guide catheter with a precurved tip may then be inserted into the sheath and advanced to coronary sinus ostium within the right atrium of the heart. A guidewire may then be advanced through the guide catheter and into the coronary sinus, and the guide catheter may be removed from the patient, leaving the guidewire behind. The delivery catheter  260  may then be advanced along the guidewire, and the guidewire may be removed. 
     The anatomy of the heart varies from patient to patient. For example, the diameter and length of the coronary sinus are patient-dependent as well as the location of coronaries arteries that may pass between the coronary sinus and the heart. One optional method step, therefore, is to introduce dye or another imaging contrast agent into the coronary sinus through the delivery catheter (such as through the Y-shaped connector  262 ) to perform a venogram while performing an angiogram on the coronary arteries in a known manner. These images will identify the relative positions of the coronary sinus and coronary arteries and will give a relative indication of the length and diameter of the coronary sinus at the target treatment site. 
     In addition, in order to calibrate the venogram with the actual size of the imaged vessels, a marker catheter may be inserted into the coronary sinus through the delivery catheter during the venogram. The marker catheter has radiopaque markings a fixed distance apart. By measuring on the venogram the distance between markings on the marker catheter, a correction factor may be devised to correct the measured diameter and length of the coronary sinus. Alternatively, radiopaque markings may be added to the delivery catheter itself, thereby eliminating the need to insert a marker catheter to obtain the correction factor measurements. Dye may also be injected during delivery and deployment of the tissue shaping device for imaging purposes. 
     After removal of the marker catheter, the delivery system may be attached to the delivery catheter. Prior to the start of the procedure, locking sleeve  220  is in its proximal-most position so that locking sleeve actuator knobs  222  are in slots  242  of release knob  240 , and screw down portion  223  is screwed against housing  226  to hold locking sleeve  220  in place. Pusher  210  and locking sleeve  220  extend from the distal end of handle  200  to the device  202  within cartridge  208 . The lengths of pusher  210  and locking sleeve  220  correspond to the length of delivery catheter  260 , as discussed below. Lengths of pusher  210  and locking sleeve  220  may be exposed between handle  200  and cartridge  208 . 
     To begin delivering tissue shaping device  202  to the patient&#39;s coronary sinus, cartridge  208  (containing tissue shaping device  202 ) and delivery catheter  260  are then connected at luer connection  268  of the main channel of Y-connector  262 . The distal tip of the delivery catheter is in place in the coronary sinus at the distal end of the target treatment site. To begin delivery of the device from cartridge  208  into delivery catheter  260 , handle  200  is advanced distally toward cartridge  208  and delivery catheter  260 . As the handle advances toward the cartridge and toward the patient, pusher  210  moves device  202  distally out of cartridge  208  into Y-connector  262  and then into delivery catheter  260 . The structure of the point where the Y-connector&#39;s second channel  270  meets the main channel  266 —specifically, reduced diameter portion  274  and tab  276 —helps prevent the tissue shaping device from expanding and getting caught at the junction of the two channels. 
     In certain embodiments of the invention, the advancing handle  200  reaches cartridge  208  when or before device  202  reaches the distal end of delivery catheter  260 . For example, in the embodiment shown in  FIGS. 14-21 , the relative lengths of device  202 , pusher  210 , handle  200  and delivery catheter  260  are such that the distal end of handle  200  reaches the proximal end of cartridge  208  before device  202  reaches the distal end of delivery catheter  260 . After this point, further advancement of handle  200  places handle housing  226  around cartridge  208  so that cartridge  208  moves inside the handle. A flat interior surface (not shown) formed in handle  200  mates with one of the flat sides of cartridge  208  to prevent relative rotation between the cartridge and the handle as control nut  250  rotates. 
     In one embodiment, rotating control nut  250  is threaded onto cartridge  208  prior to use of the system to treat a patient, as shown in  FIG. 14 . The location of control nut  250  on cartridge  208  depends on the length of the device  202  within cartridge  208  as well as the relative lengths of the pusher and delivery catheter. In this embodiment, these elements are sized and configured so that control nut  250  engages with, and snaps to, the distal end of handle  200  at the point during device delivery when device  202  has reached the distal end of delivery catheter  260 . This action engages cartridge  208  with handle  200  for controlled delivery and deployment of tissue shaping device  202 . Alternatively, control nut  250  can be disposed on the distal end of handle  200  from the start. In this case, cartridge  208  engages handle  200  through control nut  250  as soon the proximal end of cartridge  208  reaches handle  200 , which may be before device  202  has reached the distal end of delivery catheter  260 . 
     After cartridge  208  engages handle  200  through control nut  250 , all further relative movement between cartridge  208  and handle  200  is controlled by rotating control nut  208 . When tissue shaping device  202  is at the distal end of catheter  260  at the distal end of the target treatment site (as determined fluoroscopically, e.g.) the physician ceases moving handle  200  toward the patient. Instead, handle  200  (and therefore device  202 ) is held stationary while cartridge  208  and delivery catheter  260  are pulled proximally by rotating control nut  250 . This action exposes the device&#39;s distal anchor  204 , which begins to self-expand. Control nut  250  is then rotated the other direction to advance delivery catheter  260  distally to apply a force to the proximal side of anchor  204  to further expand and lock the anchor, i.e., by advancing the anchor&#39;s lock loop over its lock bump, as described above. Thus, control nut  250  acts as an actuator for expanding and locking the device&#39;s distal anchor. 
     After locking the distal anchor, a proximal cinching force is applied to the device through tether  216  to reshape the mitral valve annulus by moving handle  200  proximally away from the patient, preferably while observing the status of the patient&#39;s mitral valve regurgitation and vital signs, such as described in U.S. patent application Ser. No. 10/366,585, “Method of Implanting a Mitral Valve Therapy Device.” Contrast dye may be injected via connector  262  to visualize the anchor while cinching. When an appropriate amount of mitral valve regurgitation has been achieved, control nut  250  is rotated while holding handle  200  in place to pull delivery catheter  260  proximally with respect to tissue shaping device  202 , thereby exposing proximal anchor  206 , which begins to self-expand. 
     In one embodiment of the invention, locking sleeve  220  is used in place of the larger diameter delivery catheter to further expand and lock proximal anchor  206  in order to avoid inadvertent recapture of the proximal anchor by the delivery catheter. Screw down portion  223  of knobs  222  is loosened to permit knobs  222  to slide forward in tracks  224 , thereby advancing locking sleeve  220  distally toward anchor  206 . Locking sleeve  220  applies a distally directed force on the proximal side of anchor  206  to further expand and lock the anchor, i.e., by advancing the anchor&#39;s lock loop over its lock bump, as described above. Thus, knobs  222  act as an actuator for expanding and locking the device&#39;s proximal anchor. Expansion and locking of the proximal anchor maintains the cinching action and, therefore, the reduction in mitral valve regurgitation caused by the device&#39;s reshaping of the mitral valve annulus. 
     Alternatively, the delivery catheter can be used to expand and lock the proximal anchor in the same manner as the distal anchor. 
     The delivery system of this embodiment enables the tissue shaping device to be fully deployed before it is detached from the delivery system. If the tissue shaping device&#39;s placement is satisfactory, the device is unhitched from the delivery system. To unhitch, release knob  240  is rotated to move release knob and the attached hitch wire  218  proximally with respect to device  202 . This action pulls the distal end of hitch wire  218  out of the device&#39;s proximal anchor crimp  207  and releases the looped end of tether  216 , thereby disengaging device  202  from the delivery system. The delivery catheter, tether and hitch wire may then be removed from the patient. 
     The slots  242  in release knob  240  prevent rotation of release knob  240  when locking sleeve  220  is in its proximal-most position. This device release interlock feature helps ensure that the locking sleeve has been used to lock the proximal anchor before the tissue shaping device is disengaged from the delivery system. 
     In certain instances, after initial deployment but before disengaging the hitch wire and tether the tissue shaping device may need to be recaptured and either removed from the patient or deployed at a different site. In that case, locking sleeve  220  is advanced distally to the proximal side of proximal anchor  206  by moving knobs  222  forward in tracks  224 . While holding handle  200  stationary to hold device  202  against distal movement through the action of tether  216 , control nut  250  is rotated to advance delivery catheter  260  distally over locking sleeve  220  to and over proximal anchor  206 , deforming anchor  206  so that it fits back inside catheter  260 . In this manner, control nut  250  is used as a recapture actuator; use of the control nut to apply the recapture force helps prevent a sudden inadvertent distal advancement of the catheter when the anchor collapses and enters the catheter. Once the proximal anchor has been recaptured into the delivery catheter, the catheter is then advanced further distally to recapture distal anchor  204  in the same way. Device  202  can then be moved or removed from the patient. 
     While preferred embodiments of the present invention have been shown and described herein, it will be obvious to those skilled in the art that such embodiments are provided by way of example only. Numerous variations, changes, and substitutions will now occur to those skilled in the art without departing from the invention. It should be understood that various alternatives to the embodiments of the invention described herein may be employed in practicing the invention. It is intended that the following claims define the scope of the invention and that methods and structures within the scope of these claims and their equivalents be covered thereby.