Patent Document

CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application is a continuation of U.S. application Ser. No. 11/788,261 filed Apr. 19, 2007, which is a continuation-in-part of U.S. application Ser. No. 11/155,699 filed Jun. 17, 2005, which claims the benefit of U.S. Application Ser. Nos. 60/581,223 filed on Jun. 18, 2004, and 60/685,681 filed on May 27, 2005, all of which are incorporated herein by reference in their entirety. This application also claims the benefit of U.S. Application Ser. No. 60/795,752 filed Apr. 28, 2006, the disclosure of which is also incorporated herein by reference in its entirety. 
    
    
     FIELD OF THE INVENTION 
     The invention relates to methods and devices for occlusion or ligation of an atrial appendage. 
     BACKGROUND OF THE INVENTION 
     Embolic stroke is the nation&#39;s third leading killer for adults. Embolic stroke is also a major cause of disability. The most common cause of embolic stroke is thrombus formation in the left appendage on the atrium. In almost all atrial fibrillation (AF) patients suffering from embolic stroke, a thrombus clot forms in the appendage of the left atrium. 
     The primary therapy for the prevention of stroke in AF patients is the administration of oral anticoagulants. Although somewhat effective, there are numerous side effects, including bleeding and lifestyle compromises. Pharmacological therapies (such as Warfarin®) are not well tolerated by patients. The introduction of biomaterials into the left atrial appendage has resulted in the biomaterials eventually breaking down resulting in clot formation. The left atrial appendage has been removed by others via open chest and thoroscopic surgical approaches. Such a procedure is described by Johnson in U.S. Pat. No. 5,306,234 entitled “Method for Closing an Atrial Appendage.” The &#39;234 patent discloses a method for grasping the left atrial appendage and manipulating it into position in order to sever the tissue and remove the appendage. The wound on the heart is then sewn or clamped shut. 
     Appriva Medical, Inc. disclosed concepts for occluding the left atrial appendage from a percutaneous endocardial approach. In U.S. Pat. No. 6,152,144 entitled “Method and Device for Left Atrial Appendage Occlusion” assigned to Appriva Medical, a device and method for isolating the left atrial appendage from the inside of the heart is disclosed. A barrier or other device is anchored in the chamber of the left atrial appendage to prevent the passage of blood into and out of the chamber and thereby prevent clot formation. However, any foreign device left in the chamber of the heart is a potential thrombosis-generating site. In addition, biomaterials are known to eventually break down and result in clotting. 
     Some surgeons will remove or oversew the left atrial appendage as a concomitant procedure during other cardiac surgery. This is done under general anesthesia and may result in additional trauma to the patient. 
     While endoscopic or percutaneous approaches reduce the invasiveness of the surgical procedure, the above-described approaches have inherent limitations. Surgical removal of the left atrial appendage is very invasive and often results in loss of atrial hormones, such as atrial natriuretic peptide (ANP), and significant bleeding. In U.S. Pat. No. 6,666,861 issued to Grabek and entitled “Atrial Remodeling Device and Method,” a method is disclosed for applying a suture lasso placed endoscopically around the left atrial appendage to isolate it from the atrium. The &#39;861 patent describes using either wet cauterization to remove the tissue or leaving the isolated appendage in place. 
     Endoscopic stapling devices, suture loops tied to the base of the appendage, and clips pinching the appendage from the outside surface to the base to close the appendage are used by physicians to isolate and remove the left atrial appendage. In U.S. Pat. No. 6,488,689 issued to Kaplan and entitled “Methods and Apparatus for Transpericardial Left Atrial Appendage Closure,” a method and apparatus to close the left atrial appendage is disclosed. The &#39;689 patent describes using a grasper and a closing loop or clip applied to the outside of the left atrial appendage. The clip is applied extending toward the chamber of the atrial appendage and extending over the outside edge of the appendage. The clips of the &#39;689 patent are a U-shaped metal clip, having a spring tendency to hold its shape, being deformed to open while positioned to extend over the tissue, before the clip is allowed to return to its resting shape, having the tissue pinched between the ends of the clip. 
     SUMMARY OF THE INVENTION 
     Some embodiments of the invention provide a system for occluding a left atrial appendage of a patient. Some embodiments of the system can include a ring occluder that can be positioned around the left atrial appendage and a ring applicator to position the ring occluder with respect to the left atrial appendage. The ring applicator can include a ring spreader with a spreader hinge coupled to an upper spreader jaw and a lower spreader jaw. The ring occluder can be coupled between the lower spreader jaw and the upper spreader jaw. The spreader hinge can move between an open position in which the ring occluder has a first diameter and a closed position in which the ring occluder has a second diameter, the first diameter being larger than the second diameter. 
     Other embodiments of the invention provide a clip occluder that can be positioned around the left atrial appendage. The clip occluder can include a clip hinge coupled to an upper clip jaw and a lower clip jaw. The clip occluder can include a clip lock. A clip applicator can position the clip occluder with respect to the left atrial appendage. The clip applicator can include a clip actuator coupled to the clip occluder by an actuator suture. The actuator suture can control a distance between the upper clip jaw and the lower clip jaw. The clip applicator can be removably coupled to the clip occluder with a retention suture. 
     In some embodiments of the invention, a ring applicator can include a shaft having a handle on a proximal end and a distal end, and a lumen or channel extending from the handle to the distal end of the shaft, an actuator coupled to the handle, and a ring spreader assembly on the distal end of the shaft. In one embodiment, the ring spreader assembly may include a plurality of ring expanding members. In an alternative embodiment, the ring spreader assembly may include a spreader drive wire. A ring occluder may be releasably attached to the plurality of ring expanding members or to the drive wire. The ring occluder can be stretched to an open position by the actuator which is coupled to the ring expanding members or the drive wire to allow the ring occluder to be manipulated over tissue to be occluded. 
     In some embodiments of the invention, the occluder member, e.g., a ring occluder or clip occluder, may comprise one or more pharmacological and/or biological agents, e.g., anti-inflammatory and/or anti-arrhythmic agents and/or drugs. In some embodiments, the occluder member may include a fabric covering. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a schematic illustration of a left atrial appendage occlusion device according to one embodiment of the invention placed around the left atrium before compressing the tissue of the left atrial appendage. 
         FIG. 2  is a schematic illustration of the left atrial appendage occlusion device of  FIG. 1  clamped around the left atrial appendage. 
         FIG. 3  is a perspective view of a ring occluder on a patient&#39;s heart isolating the left atrial appendage. 
         FIG. 4  is a perspective view of a variety of ring occluders illustrating the relative size differences that are available. 
         FIG. 5  is a perspective view of a ring occluder applicator according to one embodiment of the invention. 
         FIG. 6  is a perspective view of an applicator head of the ring occluder applicator of  FIG. 5 . 
         FIG. 7  is a perspective view of the handle mechanism of the ring occluder applicator of  FIG. 5 . 
         FIG. 7A  is a perspective view of the ring occluder applicator in  FIG. 5  with a ring occluder attached. 
         FIG. 8  is a perspective view of the ring occluder applicator of  FIG. 5  with a ring occluder attached and in a stretched-open position. 
         FIG. 9A  is a side view of the ring occluder applicator of  FIG. 7  with the ring occluder in a relaxed position. 
         FIG. 9B  is a side view of the ring occluder applicator in  FIG. 7  with the ring occluder in a partially-stretched open position. 
         FIG. 9C  is a side view of the ring occluder applicator of  FIG. 7  with the ring occluder in a stretched-open position. 
         FIG. 10  is a cross-sectional schematic illustration of a left atrial appendage occlusion device according to one embodiment of the invention, before being clamped around the left atrial appendage. 
         FIG. 11  is a cross-sectional schematic illustration of the occlusion device of  FIG. 10 , after being clamped around the left atrial appendage. 
         FIG. 12  is a perspective view of the occlusion device of  FIG. 10  applied to a patient&#39;s heart. 
         FIG. 12A  is an end view of the occlusion device of  FIG. 10  applied to a patient&#39;s heart. 
         FIG. 13  is a perspective view of a clip applicator according to one embodiment of the invention. 
         FIG. 14  is a perspective view of an applicator head of the clip applicator of  FIG. 13 . 
         FIG. 15  is a perspective view of the clip applicator of  FIG. 14  with the clip attached and in a spring-biased open position. 
         FIG. 16  is a perspective view of the clip applicator of  FIG. 14  with the clip attached and in an insert position. 
         FIG. 17  is a perspective view of the clip applicator of  FIG. 14  with the clip detached and in a locked position. 
         FIG. 18  is a cross-sectional schematic illustration of a left atrial appendage occlusion device according to one embodiment of the invention, before compressing tissue of the left atrial appendage. 
         FIG. 19  is a cross-sectional schematic illustration of the occlusion device of  FIG. 18 , after being clamped around the left atrial appendage. 
         FIG. 20  is a cross-sectional schematic illustration of the occlusion device of  FIG. 20  with one or more ratcheting arms removed. 
         FIG. 21  is a cross-sectional schematic illustration of a left atrial appendage occlusion device according to one embodiment of the invention, before compressing tissue of the left atrial appendage. 
         FIG. 22  is a cross-sectional schematic illustration of the occlusion device  FIG. 22  after compressing tissue of the left atrial appendage. 
         FIG. 23  is a perspective view of an applicator for inserting and applying a left atrial appendage occluder according to one embodiment of the invention. 
         FIG. 24  is an exploded perspective view of the occluder of  FIG. 23 . 
         FIG. 25  is a perspective view of the occluder of  FIG. 24  after assembly. 
         FIG. 26  is a perspective view of the occluder of  FIG. 25  being mounted on the applicator of  FIG. 23 . 
         FIG. 27  is a perspective view of the occluder fully mounted on the applicator of  FIG. 23 . 
         FIG. 28  is a perspective view of the occluder compressed on the applicator of  FIG. 23 . 
         FIG. 29  is a perspective view of the occluder compressed and disconnected from the applicator of  FIG. 23 . 
         FIG. 30  is a perspective view of one embodiment of a device according to one embodiment of the invention. 
         FIG. 31  is a partial perspective view of the device of  FIG. 30  in use. 
         FIG. 32  is a schematic illustration of an occlusion device according to one embodiment of the invention positioned around the left atrial appendage. 
         FIG. 33  is a schematic illustration of the occlusion device of  FIG. 32  clamped around the left atrial appendage. 
         FIG. 34  is a perspective view of an adjustable band occluder according to one embodiment of the invention. 
         FIG. 35  is a perspective view of a deployed percutaneous left atrial appendage transcatheter occlusion (PLAATO) device. 
         FIGS. 36A-E  are perspective views of an endoloop left atrial appendage ligation procedure. 
         FIGS. 37A-E  are side and perspective views of an atrial septal defect repair device. 
         FIG. 38  is a schematic cross-sectional representation of a heart and a chest wall. 
         FIG. 39  is a side view of a device according to one embodiment of the invention passed through a port placed between the ribs. 
         FIG. 40  is a side view of the device of  FIG. 39  advanced toward the left atrial appendage. 
         FIG. 41  is a side view of the device of  FIG. 39  including a suction cup or grasper probe being advanced through portal tube. 
         FIG. 42  is a side view of the device of  FIG. 41  with the suction cup or grasper probe attached to an end of the left atrial appendage. 
         FIG. 43  is a side view the device of  FIG. 41  with cinch-ring support arms expanded and the left atrial appendage pulled toward a portal tube. 
         FIG. 44  is a side view of the device of  FIG. 41  with the cinch-ring support arms advanced over the left atrial appendage. 
         FIG. 45  is a side view of the device of  FIG. 41  with the cinch-ring support arms positioned over a mid to proximal left atrial appendage. 
         FIG. 46  is a side view of the device of  FIG. 41  with the cinch-ring support arms allowed to contract over the left atrial appendage and occlude a lumen of the left atrial appendage. 
         FIG. 47  is a side view of the device of  FIG. 41  with the suction cup or grasper probe removed from the portal tube. 
         FIG. 48  is a side view of a dilator/sheath assembly advanced through the portal tube. 
         FIG. 49  is a side view of the dilator/sheath assembly of  FIG. 48  with a needle or sharp wire advanced through a lumen of the dilator to puncture into the left atrial appendage lumen. 
         FIG. 50  is a side view of the dilator of  FIG. 49  advanced into the lumen of left atrial appendage and the needle retracted. 
         FIG. 51  is a side view of the dilator of  FIG. 49  with the sheath advanced over the dilator into left atrial appendage lumen. 
         FIG. 52  is a side view of the dilator of  FIG. 51  with the left atrial appendage lumen being aspirated of blood and flushed with heparinized saline to prevent thrombus formation. 
         FIG. 53  is a side view of the dilator of  FIG. 51  with the left atrial appendage being filled with heparinized saline as blood and air are removed. 
         FIG. 54  is a side view of the dilator of  FIG. 51  being advanced past the cinch ring and into the left atrium. 
         FIG. 55  is a side view of the sheath of  FIG. 51  being advanced over the dilator past the cinch ring and into the left atrium. 
         FIG. 56  is a side view of the sheath of  FIG. 51  with the dilator removed. 
         FIG. 57  is a side view the sheath of  FIG. 56  with therapeutic implements being advanced into the left atrium. 
         FIG. 58  is a side view of a balloon ablation device according to one embodiment of the invention at the right inferior pulmonary vein ostium. 
         FIG. 59  is a side view of the balloon ablation device of  FIG. 58  at the left superior pulmonary vein ostium. 
         FIG. 60  is a side view of an encircling ablation device according to one embodiment of the invention approaching the left superior pulmonary vein ostium. 
         FIG. 61  is a side view of the encircling ablation device of  FIG. 60  placed around the left superior pulmonary vein ostium. 
         FIG. 62  is a side view of a left atrial de-bulking spiral ablation device according to one embodiment of the invention placed against the posterior left atrium. 
         FIG. 63  is a side view of a high intensity focused ultrasound ablation device according to one embodiment of the invention creating a lesion over the left atrial isthmus. 
         FIG. 64  is a side view of a PFO or ASD closure device according to one embodiment of the invention being deployed in the fossa ovalis of the inter-atrial septum. 
         FIG. 65  is a side view of a linear ablation device according to one embodiment of the invention forming connecting lesions between pulmonary veins. 
         FIG. 66  is a side view of an elastic cinch ring according to one embodiment of the invention allowed to constrict down around the base of the left atrial appendage. 
         FIG. 67  is a side view of the elastic cinch ring of  FIG. 66  immediately following the procedure. 
         FIG. 68  is a side view of the elastic cinch ring of  FIG. 66  after approximately 12 weeks. 
         FIG. 69  is a perspective view of one embodiment of a device according to one embodiment of the invention. 
         FIG. 70  is a perspective view of one embodiment of a device according to one embodiment of the invention. 
         FIG. 71  is a partial cross-sectional view of one embodiment of a device according to one embodiment of the invention. 
         FIG. 72  is a perspective view of one embodiment of a pair of devices according to one embodiment of the invention. 
         FIG. 73  is a perspective view of one embodiment of a pair of devices according to one embodiment of the invention. 
         FIG. 74  is a perspective view of one embodiment of a device according to one embodiment of the invention. 
         FIG. 75  is a perspective view of one embodiment of a device according to one embodiment of the invention. 
         FIG. 76  is a perspective view of a distal portion of one embodiment of a device according to one embodiment of the invention. 
         FIG. 77  is a perspective view of a distal portion of one embodiment of a device according to one embodiment of the invention. 
         FIG. 78  is a perspective view of a distal portion of one embodiment of a device according to one embodiment of the invention. 
         FIG. 79  is a perspective view of a distal portion of one embodiment of a device according to one embodiment of the invention. 
         FIG. 80  is a perspective view of a distal portion of one embodiment of a device according to one embodiment of the invention. 
         FIG. 81  is a perspective view of a distal portion of one embodiment of a device according to one embodiment of the invention. 
         FIG. 82  is a perspective view of one embodiment of a device according to one embodiment of the invention. 
         FIG. 83  is a perspective view of a distal portion of one embodiment of a device according to one embodiment of the invention. 
         FIG. 84  is a perspective view of a distal portion of one embodiment of a device according to one embodiment of the invention. 
         FIG. 85  is a perspective view of a portion of one embodiment of a device according to one embodiment of the invention. 
         FIG. 86  is a perspective view of a portion of one embodiment of a device according to one embodiment of the invention. 
         FIG. 87  is a perspective view of a portion of one embodiment of a device according to one embodiment of the invention. 
         FIG. 88  is a perspective view of one embodiment of a device according to one embodiment of the invention. 
         FIG. 89  is a perspective view of a portion of a subassembly of one embodiment of a device according to one embodiment of the invention. 
         FIG. 90  is a perspective view of a portion of a subassembly of one embodiment of a device according to one embodiment of the invention. 
         FIG. 91  is a perspective view of a portion of a subassembly of one embodiment of a device according to one embodiment of the invention. 
         FIG. 92  is a perspective view of a portion of a subassembly of one embodiment of a device according to one embodiment of the invention. 
         FIG. 93  is a cross-sectional view of a portion of one embodiment of a device according to one embodiment of the invention. 
         FIG. 94  is a perspective view of one embodiment of a device according to one embodiment of the invention. 
         FIG. 95  is a cross-sectional view of one embodiment of a device according to one embodiment of the invention. 
         FIG. 96  is a perspective view of one embodiment of a device according to one embodiment of the invention. 
         FIG. 97  is a perspective view of a portion of a subassembly of one embodiment of a device according to one embodiment of the invention. 
         FIG. 98A  is a perspective view of a portion of a subassembly of one embodiment of a device according to one embodiment of the invention. 
         FIG. 98B  is a perspective view of a portion of a subassembly of one embodiment of a device according to one embodiment of the invention. 
         FIG. 98C  is a perspective view of a portion of a subassembly of one embodiment of a device according to one embodiment of the invention. 
     
    
    
     DETAILED DESCRIPTION 
       FIG. 1  illustrates an outline of the atrium  10  of the heart with the left atrial appendage  12  protruding therefrom.  FIG. 1  also illustrates one embodiment of an occluder  14  forming a ring  16  that is placed in a position to surround the left atrial appendage  12  adjacent to a left atrial appendage base  18 , where the left atrial appendage  12  is attached to the heart  20 . In some embodiments, the ring  16  can be constructed of an elastic material to allow it to be stretched into an open position, as shown in  FIG. 1 . The ring  16  can be allowed to return to a closed position, as shown in  FIG. 2 , to bear against the tissue of the left atrial appendage  12  in order to close off any interior connection between the atrium  10  and the left atrial appendage  12 . 
       FIG. 3  illustrates the ring  16  attached to a patient&#39;s heart  20  to isolate the left atrial appendage  12  from the atrium  10 . In some embodiments, the material of the ring  16  can be biocompatible to allow the ring  16  to be left on the heart  20  permanently. Optionally, the ring  16  may have tissue engaging surfaces for enhanced positionability and/or tissue engagement. The tissue engagement surfaces may comprise bumps, detents, grooves, ridges, ribs or the like. The ring  16  may also include biocompatible coatings for any of the predetermined purposes disclosed herein. The biocompatible coatings may include a pharmacological agent (e.g. a controlled-release agent) for purposes of encouraging tissue ingrowth, affording local apoptosis for therapeutic reasons, local necrosis, revascularization, arrhythmia control, infection control, anti-bacterial, fluid balance (i.e. atrial natritic peptide replacement), etc. 
       FIG. 4  illustrates different relative sizes of rings  16  that can be used to accommodate different anatomy requirements of the patient. In one embodiment, the ring  16  can be manufactured with radio opaque qualities, such as micro-sized glass beads  26  molded into the material of the ring  16 . Alternatively, the ring  16  can be made radio opaque by the addition of glass or metallic fibers  28  in the material of the ring  16 . In some embodiments, the ring  16  can be entirely biocompatible to allow for use for the life of the patient. The ring  16  can have size variations in its inner diameter  30  along a contact surface  32 . The ring  16  can also have different cross-sectional shapes, such as oval, rectangular, square, etc. 
     To apply the ring  16  to a patient, a ring applicator  34 , as shown in  FIG. 5 , can be used. In some embodiments, the ring applicator  34  can include a shaft  36  with a handle  38  on a proximal end and a ring spreader  40  on a distal end. The ring spreader  40  can include an upper spreader jaw  42  and a lower spreader jaw  44 , each connected to a spreader hinge  46 . A jaw actuator  48  on the handle  38  can include a knob  50 . 
     In some embodiments, the spreader hinge  46  can include a four-bar assembly  52  for use in moving the upper spreader jaw  42  and the lower spreader jaw  44  substantially in parallel. The four-bar assembly  52  can include a first distal link  54  and a second distal link  56 , as shown in  FIG. 6 . The first distal link  54  can include a distal end pivotally attached to the upper spreader jaw  42  at a top distal pivot  58 . The second distal link  56  can include a distal end pivotally attached to the lower spreader jaw  44  at a lower distal pivot  60 . The first distal link  54  can include a proximal end pivotally attached to the shaft  36  and to a proximal end of the second distal link  56  at a distal shaft pivot  57 . As a result, the first distal link  54  can be pivotally linked to the second distal link  56 . 
     The ring spreader  40  can be moved from a relaxed closed position (as shown in  FIG. 9A ) having the upper spreader jaw  42  in close proximity to the lower spreader jaw  44  to an open position (as shown in  FIGS. 8 ,  9 B, and  9 C) by the jaw actuator  48 . In the open position, the upper spreader jaw  42  can be spaced from the lower spreader jaw  44  by a larger distance than in the closed position. 
     In some embodiments, as shown in  FIG. 6 , the ring  16  can be removably attached to the ring spreader  40  by one or more sutures tied between the handle  38  and the ring  16 . In one embodiment, the ring  16  can be tied on the front, back, top, and bottom to uniformly open the ring  16  for application to a tissue appendage. A front suture  66  and an upper suture  68  can be attached to the jaw actuator  48  and can loop inside the shaft  36  to the upper spreader jaw  42  and around the ring  16  at spaced intervals. A proximal suture  70  and a lower suture  72  can be similarly attached to the jaw actuator  48  and can extend inside the shaft  36  to the lower spreader jaw  44  and around the ring  16  at spaced intervals. 
     As shown in  FIG. 6 , the upper spreader jaw  42  can include a first feed slot  74  having a first distal aperture  75  extending through the upper jaw  42  and a first upper aperture  79  extending through the upper jaw  42 . The first upper aperture  79  can be disposed between the first distal aperture  75  and the spreader hinge  46 . The upper spreader jaw  42  can include a return slot  76  parallel to the first feed slot  74 . The return slot  76  can include a second distal aperture  77  in proximity to the first distal aperture  75  and a second upper aperture  81  in proximity to the first upper aperture  79 . In some embodiments, the first and second upper apertures  79  and  81  can both extend through the upper jaw  42 . 
     As shown in  FIG. 7A , the lower spreader jaw  44  can include a similar configuration to the upper spreader jaw  42 . The lower spreader jaw  44  can include a second feed slot  65  with a first lower aperture  67  and a first proximal aperture  69 . The first proximal aperture  69  can be disposed between the first lower aperture  67  and the spreader hinge  46 . A second return slot  71  can be formed on the lower spreader jaw  44  substantially parallel to the second feed slot  65 . The second return slot  71  can include a second lower aperture  73  in proximity to a first lower aperture  67  and a second proximal aperture  53  in proximity to the first proximal aperture  69 . The second proximal aperture  53  can be disposed between the spreader hinge  46  and the second lower aperture  73 . 
     The feed slots  65 ,  74  can be used to direct the sutures attached at the handle  38  to the jaw actuator  48 . The sutures  66 ,  68 ,  70 ,  72  can be directed along the spreader jaws  42 ,  44  and directed to pass through the spreader jaws  42 ,  44  at the apertures  67 ,  69 ,  75 ,  79 . The sutures can  66 ,  68 ,  70 ,  72  then loop around the ring  16  at predefined locations. The sutures  44 ,  42  can also pass through the apertures  53 ,  73 ,  79 ,  81  and along the return slots  71 ,  76  to return through a lumen to attach to the jaw actuator  48 . The front suture  66  can have a first end attached to the jaw actuator  48 . The front suture  66  can extend through the handle  38 , along the first feed slot  74 , through the first distal aperture  75 , and around the ring  16  in a single loop defining the front portion of the ring  16 . The front suture  66  can also extend back through the second distal aperture  77 , along the first return slot  76 , and through the handle  38  to a second end connected to the jaw actuator  48 . Likewise, the upper suture  68  can extend through the handle  38 , along the first feed slot  74 , through the first upper aperture  79 , and around the ring  16  in a single loop defining the upper portion of the ring  16 . The upper suture  68  can also extend back through the second upper aperture  81 , along the first return slot  76 , and through the handle  38  to a second end connected to the jaw actuator  48 . 
     The lower suture  72  can have a first end attached to the jaw actuator  48 . The lower suture  72  can extend through the handle  38 , along the second feed slot  65 , through the first lower aperture  67 , and around the ring  16  in a single loop defining the lower portion of the ring  16 . The lower suture  72  can also extend back through the second lower aperture  73 , along the second return slot  71 , and through the handle  38  to a second end connected to the jaw actuator  48 . Likewise, the proximal suture  70  can extend through the handle  38 , along the second feed slot  65 , through the first proximal aperture  69 , and around the ring  16  in a single loop defining the proximal portion of the ring  16 . The proximal suture  70  can also extend back through the second proximal aperture  53 , along the second return slot  71 , and through the handle  38  to a second end connected to the jaw actuator  48 . 
       FIG. 7  illustrates a torque screw  82  having a hex end  84  channeled in the handle  38  and attached to the jaw actuator  48 , according to one embodiment of the invention. When the knob  50  is rotated, the torque screw  82  can rotatably traverse to move the hex end  84  in the handle  38  toward the ring spreader  40  or toward the knob  50 , depending on which direction the knob  50  is rotated. The sutures  66 ,  68 ,  70 ,  72  can be attached to the hex end  84  using knots and can extend to loop around the ring  16  in the ring spreader  40 . As the knob  50  is turned to traverse the hex end  84  away from the ring spreader  40 , the sutures  66 ,  68 ,  70 ,  72  can tighten to bear against the ring  16  and the spreader jaws  42 ,  44  in order to overcome the elasticity of the ring  16  and move the spreader jaws  42 ,  44  to the open position, as shown in  FIGS. 8 and 9C . The spreader jaws  42 ,  44  can be guided in a substantially parallel path by the four-bar assembly  52  in order to stretch the ring  16  to the open position. In some embodiments, the hex end and the torque screw  82  are replaced by a linear trigger grip. By squeezing the grip handle, the spreader jaws are spread as described above. 
     In some embodiments, as shown in  FIGS. 9A-9C , the spreader hinge  46  can include a top proximal link  86  and a lower proximal link  88 . The top proximal link  86  can include a first end pivotally attached to the shaft  36  and a second end pivotally connected to the upper spreader jaw  42 . The lower proximal link  88  can include a first end pivotally connected to the shaft  36  and a second end pivotally connected to the lower spreader jaw  44 . The proximal links  86 ,  88  can function with the distal links  54 ,  56  to move the upper spreader jaw  42  in a substantially parallel relationship with respect to the lower spreader jaw  44 . 
     The sutures  66 ,  68 ,  70 ,  72  can act as a retainer to hold the ring  16  in the ring spreader  40 . The sutures  66 ,  68 ,  70 ,  72  can also act as a portion of the jaw actuator  48  by pulling the ring spreader  40  toward the handle  38  to force the spreader hinge  46  to pivot at the four-bar assembly  52 , causing the spreader jaws  42 ,  44  to spread away from one other and stretching the ring  16  open. The sutures  66 ,  68 ,  70 ,  72  can open the ring  16  into a substantially rectangular shape as shown in  FIG. 9C . 
     As shown in  FIG. 10 , a left atrial appendage chamber  94  can be positioned within a locking clip  96  in an open position.  FIG. 11  illustrates the chamber  94  compressed by the locking clip  96  in the closed position. The locking clip  96  can include a lower clip jaw  118  made of an elastic material and an upper clip jaw  124  connected to the lower clip law  118  at a clip hinge  122 . In one embodiment, the locking clip  96  can be formed from a single piece of elastic material  120  and can define the clip hinge  122  integrally with the lower clip jaw  118  and upper clip jaw  124 . The locking clip  96  can also include a clip lock  126  (e.g., such as a clip barb  128 ) on the upper clip jaw  124 , that is adapted to engage the lower clip jaw  118  at a lock receiver  130  to substantially permanently affix the upper clip jaw  124  to the lower clip jaw  118 .  FIGS. 12 and 12A  illustrate an application of the locking clip  96  on a patient&#39;s heart. 
       FIG. 13  illustrates one embodiment of a clip applicator  98  for delivering a locking clip  96  into a patient through an incision in a closed-chest routine. The clip applicator  98  can include a shaft  36  having a handle  38  on a proximal end, a clip actuator  108  on the handle  38 , and a locking clip  96  coupled to a distal end. 
     The clip actuator  108  can be used to move the locking clip  96  from an open, unlocked position to a closed, locked position. The clip actuator  108  can include an actuator suture  110  having a first end attached to the handle  38  and extending through a lumen  112  (as shown in  FIG. 14 ) in the handle  38 . The actuator suture  110  can engage the locking clip  96  through a first feed aperture  119  in the lower jaw  118  and can extend through a first actuator aperture  125  in the upper clip jaw  124  of the locking clip  96 . The actuator suture  110  can loop over the upper clip jaw  124  and can pass through a second actuator aperture  123  in the upper clip jaw  124 . The actuator suture  110  can also extend through a second feed aperture  117  in the lower jaw  118  and back through the handle  38  to a second end attached to the clip actuator  108 . Alternatively, the actuator suture  110  can be looped outside the handle  38 , so that the operator can pull the actuator suture  110  manually to draw the upper clip jaw  124  to engage the lower clip jaw  118  when the locking clip  96  is in position to engage the left atrial appendage  12 . 
     The first feed aperture  119  can be positioned through the lower clip jaw  118  to allow the actuator suture  110  to pass through the lower clip jaw  118  to the upper clip jaw  124 . The upper clip jaw  124  can include the first and second actuator apertures  125 ,  123  that can allow the actuator suture  110  to loop around the upper clip jaw  124 , while retaining, a position near the clip lock  126  on the upper clip jaw  124 . The clip actuator  108  can be a movable actuator, similar to the torque screw assembly on the ring applicator shown in  FIGS. 7 and 8 , or alternatively, a thumb slide or lever. The clip actuator  108  can pull the actuator suture  110  to engage the locking clip  96  by pulling the upper clip jaw  124  into engagement with the lower clip jaw  118  at the clip lock  126 . The actuator suture  110  can include a first end coupled to the clip actuator  108 . The first end can extend through the lumen  112  passing through the lower jaw  118  to loop around the upper clip jaw  124  and back through the lower clip jaw  118  to terminate at the handle  38 . In this manner, the clip actuator  108  can bear against the actuator suture  110  to pull on the open end of the upper clip jaw  124  and to overcome the spring tenancy of the clip hinge  122  in order to draw the upper clip jaw  124  into a locking engagement with the lower clip jaw  118 . 
     The lower clip jaw  118  can include an engagement connection  121  to releasably connect the locking clip  96  to the clip applicator  98  with a retention suture  111  (as shown in  FIG. 14 ). The retention suture  111  can removably attach the locking clip  96  to the clip applicator  98 . The retention suture  111  can include a first end coupled to the handle  38 . The first end can extend from the handle  38  to the locking clip  96  to releasably engage the lower clip jaw  118 . As shown in  FIG. 14 , the retention suture  111  can loop into an engagement portion  121  of the lower clip jaw  118  so that the retention suture  111  may be cut at one end. The retention suture  111  can be cut at the handle  38  to draw the retention suture  111  out of the patient and remove the clip applicator  98 , while leaving the locking clip  96  attached to the lower atrial appendage  12 . As shown in  FIG. 15 , the engagement connection  121  can include an aperture in the lower clip jaw  118 , adjacent the clip lock  126 , that can allow the retention suture  111  to pass into and around a portion of the lower clip jaw  118  and back to the handle  38 . 
     As shown in  FIGS. 14-17 , a clip stop  114  and two alignment pins  116  can be attached to a distal end of the handle  38 . The lower clip jaw  118  can include one or more receivers (not shown) to receive the alignment pins  116  in order to hold the locking clip  96  in alignment with the shaft  36  and to prevent rotation of the locking clip  96  with respect to the shaft  36 . The clip stop  114  can include a retractable element in the shaft  36  that can extend out to a position between the lower clip jaw  118  and the upper clip jaw  124 . The clip stop  114  can extend out to engage the locking clip  96  as the clip applicator  98  and the locking clip  96  are passed through a lumen, tube, or endoscope, while the operator is inserting the locking clip  96  into a patient, in order to prevent the locking clip  96  from inadvertently locking. After insertion through the lumen, the clip hinge  122  can bear against the clip jaws  118 ,  124  to open the locking clip  96  for positioning around the base of the left atrial appendage  12  or other target tissue, and the clip stop  114  can be retracted into the shaft  36 . 
       FIG. 16  illustrates the clip  96  in an insertion position in which the clip stop  114  is removably engaged between the upper clip jaw  124  and the lower clip jaw  118 . The insertion position can help prevent the clip lock  126  from engaging as clip applicator  98  and the locking clip  96  are passed into a patient&#39;s chest through an incision (possibly in a cannula or endoscope). The clip actuator  108  can be used to pull the actuator suture  110  to move the clip stop  114  into the shaft  36  away from the clip jaws  118 ,  124 . The clip actuator  108  can bring the clip jaws  118 ,  124  into a position to lock the clip lock  126  and to hold the locking clip  96  in a locking position, as shown in  FIG. 16 . 
     As shown in  FIG. 17 , the locking clip  96  can be disengaged from the clip applicator  98  by cutting the retention suture  111  at the handle  38  and drawing the retention suture  111  out of the clip applicator  98 . Likewise, the actuator suture  110  can be released from the clip actuator  108 , can be cut, and can be pulled out of the patient and from the clip applicator  98 . The locked locking clip  96  can releasably slide off of the alignment pins  116  and can remain attached to the left atrial appendage  12  when the clip applicator  98  is removed. 
       FIGS. 18-20  illustrate one embodiment of an occluder including a clamp with a first pressure plate  152  and a second pressure plate  154 . The first and second pressure plates  152 ,  154  can each have one or more end holes  151 . A ratcheting mechanism can include teeth  155  on connector rods  153  and a receiver  157  for receiving the connecting rod  153  and engaging the teeth  155  to substantially permanently hold the plates  152 ,  154  in spaced relation to one other in order to isolate the chamber of the left atrial appendage  12 . As shown in  FIG. 20 , the receivers  157  can be positioned onto the connector rods  153  extending from the second pressure plate  154 . The receivers  157  can bear against the first pressure plate  152  to hold the plates  152 ,  154  in a predefined spaced relation. As shown in  FIG. 21 , the ends of the connector rods  153  extending from the receivers  157  can be clipped off after the desired claming is achieved. 
       FIGS. 21-22  illustrate one embodiment of an occluder in which the pressure plates  152 ,  154  can be configured with a tie channel  156  passing through each plate  152 ,  154  from one end to another. A tie  158  can be passed through the tie channels  156  to connect the first and second plates  152 ,  154  together. The plates  152 ,  154  can be positioned to clamp down on the base of the left atrial appendage  12  to close off the left atrial appendage chamber  94 . 
       FIGS. 23-29  illustrate one embodiment of a loop clip  174  and a loop clip applicator  172  for engaging the left atrial appendage at its base in order to close the chamber of the left atrial appendage. The loop clip  174  can include a lower clip jaw  176  and a loop  178 . The loop  178  can include a fixed end  187  attached to the lower clip jaw  176  and teeth  182  that extend to a slidable end  185 . The loop  178  can engage the lower clip jaw  176  at a clip lock  183  to substantially permanently clamp by bearing against tissue trapped between the loop  178  and the lower clip jaw  176 . 
       FIG. 26  illustrates an actuator attachment  180  that can include a retention suture  111  extending from the handle  38  to an engagement portion  177  on the loop clip  174 . The engagement portion  177  can include an aperture through the loop clip  174  to allow the retention suture  111  to extend from the handle  38 , through the shaft  36  around the engagement portion, and back to the handle  38 . The retention suture  111  can releasably retain the loop clip  174  on the loop clip applicator  172 , until the loop clip  174  is secured around the left atrial appendage. The retention suture  111  can be cut at one end and drawn out of the patient to leave the loop clip  174  engaged. 
       FIG. 24  illustrates an actuator suture  110  attached to the slidable end  185  of the loop clip  174 . The actuator suture  110  can be removably attached to the slidable end  185  of the loop  178  by looping through an actuator aperture  180 . The fixed end  187  of the loop  178  can be attached to the lower clip jaw  176  while the remainder of the loop  178  having teeth  182  can slidably engage the clip lock  183 . 
     As shown in  FIG. 27 , the loop clip  174  can be attached to the loop clip applicator  172  and maintained in an insertable position. The loop clip  174  and the shaft  36  can be inserted into the patient&#39;s chest to bring the loop  178  to a position adjacent the left atrial appendage  12 . The loop clip  174  can be manipulated to a position where the lower jaw clip  176  is adjacent the base of the left atrial appendage  12  and the loop  178  extends around the left atrial appendage  12 . The actuator suture  110  can be attached to an actuator  108 , which can include a knob  50  and a torque screw  82 , as shown in  FIG. 23 . The knob  50  can be turned to traverse the hex head of the torque screw  82  to bear against the actuator suture  110  in order to pull the slidable end  185  of the loop  178  through the clip lock  183  where the teeth  182  can be engaged by the lower jaw clip  176  to substantially permanently hold the loop  178  in position. The knob  50  can be turned until the loop  178  is pulled as tight as desired against the tissue of the left atrial appendage  12  in order to isolate the chamber from the atrium. Alternatively, the actuator suture  110  can be looped outside the handle  38  to be pulled manually by the operator to lock the loop clip  174  in relation the lower clip jaw  176 . Other embodiments of the actuator  108  can include a linear trigger grip, a linear slider, etc. 
     As shown in  FIG. 28 , the loop clip  174 , which is shown in a position for encircling and occluding the left atrial appendage to close the chamber  94 , can be disengaged from the loop clip applicator  172  by cutting one end of the retention suture  111  and pulling the retention suture  111  from around the engagement portion  177  and out of the patient&#39;s body. As shown in  FIG. 28 , the loop  178  can be engaged by the teeth  182  to the lower clip jaw  176  to a closed position. The loop  178  can be disengaged from the loop clip applicator  172  by cutting one end of the actuator suture  110  and pulling the actuator suture  110  through the actuator aperture  180  and out of the patient. 
     Some embodiments of the invention provide a tool designed to place a ring-style left atrial appendage occlusion device. The tool can include a handle with a long neck. An upper and a lower jaw can be attached to the handle with a four-bar assembly on a distal end and a knob  50  and a torque screw  82  on a proximal end. Some embodiments of the tool can include four separate sutures (2 front and 2 rear) that can loop around a ring and then into the upper and lower jaws. The sutures can be positioned in slots on outside edges of the upper and lower jaws and down into the handle. A retaining suture can be positioned through the lower jaw of a ring into a distal end of the handle, and the loop can be completed outside a proximal end of the tool. The retaining suture can be used to pull and then hold the ring tight against the distal end of the handle. Two holes can be positioned in an end of the lower jaw of the ring. Alignment pins can be inserted into the two holes to help hold and position the ring. After routing through the handle, the retaining suture can be positioned into the hex end of the torque screw and through to the other side where the retaining suture are then tied off. 
     According to some embodiments of a method of the invention, a port can be placed in the patient&#39;s chest so that when the ring is placed and opened, the left atrial appendage can be pulled into the opening with a grasper, a vacuum source (e.g. a cone), an adhesive tool tip, a cryo device for temporarily sticking to tissue, etc. A neck of the tool can include articulation to aid in placement of the ring. A distal end of the tool can be guided through the port and placed near the left atrial appendage. As the torque screw is turned, the upper and lower jaws open parallel to one another. Continuing to turn the torque screw stretches the ring open. Other methods of actuation can be used to pull the sutures, such as a trigger, slider, etc. When the ring is fully opened, the left atrial appendage can be pulled between the upper and lower jaws until properly located. The torque screw can be turned in the opposite direction to release tension on the sutures and relax the ring around the left atrial appendage. The torque screw can be tightened and relaxed multiple times, if necessary to achieve proper placement. Once the ring is properly positioned, the sutures can be cut (either near the ring or on a proximal end of the tool) to release the ring, and the tool can be retracted. An inside edge of the port can be used to close the upper and lower jaws so the tool can be removed. 
     Other embodiments of the invention provide a tool designed to place a clip-style left atrial appendage occlusion device. The clip can be a rigid one-piece clip with a snap-in lock on one end. The clip can also include a living hinge that is spring biased open on the other end. However, other embodiments of the tool can be used with other types of rigid clips, as well as a different hinge or latching mechanism. The tool can include a handle with a long neck. Two separate suture loops can be positioned along the length of the handle inside the neck. A stop on a distal end of the tool can be actuated on a proximal end of the tool. An actuation suture can be positioned through an upper clip jaw of the left atrial appendage clip, then through a lower clip jaw, into a distal end of the handle and complete a loop outside a proximal end of the handle. A port can be created in the patient&#39;s chest such that when the clip is positioned near the left atrial appendage, the left atrial appendage can be pulled between the upper and lower clip jaws with a grasper. The neck on the tool can articulate to aid in placement of the clip. The stop can be placed in its forward position to keep the upper clip jaw from latching while pushing it through the port. The clip can spring open after it has passed through the port. The handle can be used to position the clip near the left atrial appendage and the left atrial appendage can be pulled between the upper and lower clip jaws with a grasper. Once the clip is positioned on the left atrial appendage as desired, a stop actuation knob  50  can be pulled back to retract the stop. The actuation suture can be pulled (or actuated with a trigger, slide, screw, etc.) until the upper clip jaw snap latches into the lower clip jaw. The left atrial appendage is then occluded. The sutures can be cut and pulled through the handle, which can release the clip. The sutures can be cut with a scalpel, scissors, or other surgical instruments, or the sutures can be cut with a mechanism that is built into the tool itself. The tool can then be removed from the port. 
     Some embodiments of the invention provide a tool designed to place a loop-clip style left atrial appendage occlusion device. The tool can include a handle with a long neck. The tool can include two separate suture loops that can be positioned through the length of the handle and a shaft. The tool can include a knob  50  and a torque screw on a proximal end of the handle and the shaft. The loop clip  174  can include a rigid base with a flexible loop that can include one-way teeth molded into it. The loop can wrap around one end of the rigid member and through a slot with a locking snap (like a cable tie). This allows the loop to be pulled in, but not release. The end of the loop can include a hole that a suture can be routed through. The suture can be positioned into the distal end of the placement device, can be positioned through the handle, into the hex end of the torque screw, and tied off on an opposite end. A retaining suture can be positioned through a hole in an end of the loop clip, then into a distal end of the placement device, positioned through the handle, and tied off on a proximal end of the tool. The retaining suture can be used to pull and hold the loop clip tight against a distal end of the handle. An alignment boss on an end of the handle can be inserted into a matching slot on the loop clip to ensure proper alignment. A port can be created in the patient&#39;s chest so that when the loop clip is positioned, the left atrial appendage can be pulled between the loop and the base with a grasper. The neck on the placement tool can articulate to aid in placement of the loop clip. The flexible loop can be pushed down to place the loop clip through the port, then once it is through, the loop can return to its original shape. The handle can be used to position the loop clip near the left atrial appendage and the left atrial appendage can be pulled inside the loop with a grasper. Once the loop clip is positioned on the left atrial appendage as desired, turning the torque screw can gradually tighten the loop (a trigger, slide, etc. could also be used to tighten the loop). The torque screw can be turned until the loop is tight enough to occlude flow and remain securely placed. After the loop is tight enough, the actuation suture and the retaining suture can be cut and pulled through the handle. The tool can then be removed from the port. 
     Some embodiments of the invention include a device and method for occlusion or ligation of an atrial appendage or other tissue. The method and applicators disclosed herein describe a minimally-invasive approach to ligation of an atrial appendage, specifically, of the left atrial appendage of patients with atrial fibrillation. Some embodiments of the invention include a method and apparatus to access the left appendage through a small incision and the use of a delivery tool to apply an occluder to the appendage. The tool can be used to grasp the appendage to help stabilize the appendage to allow for application of the ligation device. The ligation device may be applied and left behind as a permanent implant. 
     Some embodiments of the invention include a device and procedure that can occlude the left atrial appendage from the body of the left atrium—thereby substantially preventing the formation of a clot within the appendage and a subsequent embolism. Some embodiments of the invention include an implantable device and applicator for substantially permanently occluding the left atrial appendage. Some embodiments of the invention include a device and procedure that is minimally invasive to apply a device as a simple and quick method to deliver therapy to prevent embolic strokes. Some embodiments of the invention include a device and procedure that does not require the use of blood-contacting biomaterials. Some embodiments of the invention include a device and procedure that results in tissue necrosis at the left atrium/left atrial appendage junction that is necessary to help prevent reentry. Some embodiments of the invention include a device and procedure that places a device to occlude while preserving the tissue of the left atrial appendage for the production of atrial hormones. Some embodiments of the invention include a device and procedure with a substantially permanently-implanted clamp used for occluding the left atrial appendage. Some embodiments of the invention include a device and procedure that is applied from the exterior of the heart, which may be accessed by a sternotomy, thoracotomy, minimally invasive, endoscopic or other means. Some embodiments of the invention include a device and procedure that may be practiced by a number of different embodiments of the clamping mechanism as disclosed herein. 
       FIG. 30  illustrates a device  200  for ligation of an atrial appendage. The device  200  can include a ring applicator or delivery tool  202  and an occlusion member or ring  214 . In one embodiment, the occlusion ring  214  can be made of a 30 A durometer silicone rubber, although other hardnesses of silicone or other materials, such as polyurethane can be used. The ring  214  can be covered with a material such as Dacron® polyester to promote tissue ingrowth or prevent ring slippage after placement or to spread the load bearing surfaces of the ring. The ring  214  can be generally expandable for placement around the atrial appendage. The delivery tool  202  can be used to expand the ring  214 . The delivery tool  202  can include a shaft  220  and a handle  230  coupled to shaft  220 . The delivery tool  202  can be sized for reaching an atrial appendage through an opening in the patient&#39;s chest, for example, through a sternotomy or thoracotomy. The delivery tool  202  can include a tissue-grasping member  210 . The tissue-grasping member  110  can be a mechanical grasping member, for example, hooks, barbs, or graspers, or it can be a suction grasping member (as shown in  FIG. 30 ), or it can be an adhesive. The delivery tool  202  can include one or more suction lumens fluidly coupled to suction grasping member  210 . The suction lumens can pass through the shaft  220  and/or handle  230 , or portions thereof. The suction grasping member  210  can be coupled to a suction source. The tissue-grasping member  210  can be used to grasp the atrial appendage and pull it through ring  214 . In one embodiment, the tissue-grasping member  210  can be moved distally and/or proximally relative to shaft  220 . In one embodiment, the delivery tool  202  can include a mechanism for controllably moving the tissue-grasping member  210 . This mechanism can be located at or near the handle  230 . 
     The delivery tool  202  can include a ring spreader  240  having ring-expanding members  242  used to hold and expand the ring  214 . The ring spreader  240  can be coupled to a distal end of shaft  220 . In one embodiment, the delivery tool  202  can include multiple ring-expanding members  242 , for example, four, as shown in  FIG. 30 . Alternatively, the delivery tool  202  can include three or five expanding members  242 , for example. The ring  214  can be releasably coupled or attached to a distal end of ring-expanding members  242 , for example, via one or more sutures  250 . The sutures  250  can loop around the ring  214 . The ends of the sutures  250  can pass through one or more lumens within the ring expanding members  242 , the shaft  220 , and the handle  230 . In one embodiment, one or more portions of the sutures  250  can be exposed at or near distal or proximal ends of the handle  230 . For example, portions of sutures  250  can be exposed at a suture cutting location  270 . Exposure of the sutures  250  at or near the handle  230  can enable the release of the ring  214  from the delivery tool  202  remotely. In one embodiment, the sutures  250  can be cut and removed, thus releasing the ring  214  from the delivery tool  202 . Cutting the sutures  250  can release the ring  214  from the ring-expanding members  242 . In one embodiment, the delivery tool  202  can include one or more suture cutting members. 
     As shown in  FIG. 30 , the handle  230  can include a ring expansion mechanism  260  used to control the expansion of the ring  214 . The ring expansion mechanism  260  can be coupled to the ring-expanding members  242 . The ring expansion mechanism  260  can control movement of the ring expanding members  242  from a closed or collapsed configuration to an open or expanded configuration, as shown in  FIG. 30 . In one embodiment, the ring expansion mechanism  260  can include a screw mechanism. The ring expansion mechanism  260  can control movement of the ring-expanding members  242  into and out of shaft  220 . The pulling of the ring-expanding members  242  into the shaft  220  can collapse the ring-expanding members  242  into a closed configuration. The pushing of the ring-expanding members  242  out of the shaft  220  can expand the ring-expanding members  242  into an open configuration. The ring-expanding members  242  can be spring biased into an open expanded configuration. In one embodiment, the ring expansion mechanism  260  can be located at or near distal or proximal ends of the handle  230 . In one embodiment, the ring expansion mechanism  260  can include one or more knobs  261  and one or more threaded members  262 , as shown in  FIG. 30 . 
     As shown in  FIG. 31 , the delivery tool  202  can be placed around the left atrial appendage  12  of a heart  20 .  FIG. 31  schematically illustrates the structure of the left and right atria  11  and  21 , respectively, as viewed from a posterior aspect, including the bases of the pulmonary veins  23  and the bases of the superior vena cava and inferior vena cava  25  and  27 , respectively, which enter the right atrium  21 .  FIG. 31  also schematically illustrates the left and right atrial appendages  12  and  22 , respectively. 
       FIGS. 32 and 33  schematically illustrate an outline of the left atrium  11  of the heart  20  with the left atrial appendage  12  protruding therefrom. The ring  214  can be placed in a position to surround the left atrial appendage  12  adjacent to the left atrial appendage base  18  where the left atrial appendage  12  is attached to the heart  20 . The ring  214  can be made of an elastic material to allow it to be stretched into an open or expanded position, as shown in  FIG. 32 . The ring  214  can be allowed to return to a closed or collapsed position, as shown in  FIG. 33 , in order to bear against the tissue of the left atrial appendage  12  and to substantially close off any interior connection between the left atrium  11  and the left atrial appendage  12 . 
     As shown in  FIG. 32 , the ring  214  can be attached to a patient&#39;s heart  20  to isolate the left atrial appendage  12  from the left atrium  11 . In some embodiments, multiple rings  214  can be placed successively more and more proximal to the base  18  of the left atrial appendage  12 . The elastic material of the ring  214  can be any biocompatible material, thereby allowing the ring  214  to be left on the heart  20  permanently. In one embodiment, the ring  214  can have different relative sizes to accommodate different anatomy requirements of the patient. The ring  214  can be manufactured with radio opaque qualities, such as micro-sized glass beads molded into the elastic material. Alternatively, the ring  214  can be made radio opaque by the addition of glass or metallic fibers in the elastic material. The ring  214  can be entirely biocompatible to allow for use for the life of the patient. The ring  214  can have size variations in its inner diameter along a contact surface. 
     In one embodiment, surgical access to the left atrial appendage can be through a left-sided thoracotomy or laparoscopic port incision. The delivery tool and attached collapsed ring can be inserted through the left thoracotomy access. The ring can then be expanded. The left atrial appendage can be grasped and drawn or pulled through the expanded ring. The ring can be positioned toward the base of the left atrial appendage and released from the delivery tool. The delivery tool can then be removed from the patient, and the incision can be closed. Various imaging methods can be employed before, during, and after the tissue occlusion procedure. For example, contrast fluoroscopy, trans-thoracic ultrasound, and/or trans-esophageal echo (TEE) can be employed. Other surgical approaches are possible including sub-xyphoid. 
     As shown in  FIG. 34 , some embodiments of the invention provide an adjustable band occluder  314 . The adjustable band occluder  314  can include a band  316 , a loop  318 , and an adjustment mechanism  320 . The size of the loop  318  can be varied by moving the adjustment mechanism  320  along the length of the band  316 . The adjustable band occluder can be locked in a fixed position by any suitable means, such as, but not limited to, a crimper region, a ratchet mechanism or other mechanical engagement structure, or other suitable locking mechanism. 
     Some embodiments of the invention address a number of problems, such as surgical access to the endocardial surfaces of the atrial chambers of a beating heart and permanent closure of the atrial appendage volume. These problems have been addressed by others using various methods and devices, such as percutaneous catheters. The right atrium may be accessed via transvenous catheters placed through a femoral vein in the groin, as well as through superior veins such as the subclavian, brachiocephalic, or jugular veins. The left atrium is more difficult to reach transvenously, requiring first, right atrial access followed by a transseptal puncture through the fosa ovalis of the inter-atrial septum into the left atrium. With these transvenous methods, only relatively small diameter catheters can be passed through the vasculature. In addition, these devices must be navigated using fluoroscopic guidance or some form of electronic navigation. 
     Positioning and placement of the therapeutic elements of such catheters can be a challenge, because the movement is controlled remotely from the point of venous access. From point of entry into the body to the therapeutic end of the catheter, the distance may be 70-110 cm through a difficult path. In cases where tissue contact force is critical, this can be a significant problem. Stability of the catheter tip is an issue in a beating heart compared to firm control possible with much shorter and more rigid surgical implements. A number of commercially-available catheters may be able to be positioned in most areas of the atria, but only one catheter-based device has been developed to permanently close off the left atrial appendage following a procedure. This device, known as PLAATO (percutaneous left atrial appendage total occlusion) must be carefully sized to allow positioning within the left atrial appendage such that it is retained in position distal to the ostium with the left atrial chamber. This presents a significant risk that the device may be released into the atrium and pass into the left ventricle and become entangled in the chordae tendinae supporting the mitral valve or become lodged in the left ventricular outflow tract or aorta. The risks of such a procedure were documented in an abstract by Fischer at the 2005 meeting of the American College of Cardiology—Evelyn Fischer, et al., “Left Atrial Appendage Occlusion to Prevent Stroke in Suboptimal Warfarin Candidates: Current Results of the European Multicenter Registry Trial,” American College of Cardiology, Abstract presented at 2005 National Meeting, which is herein incorporated by reference in its entirety. 
     The atria may be accessed through sternotomy, thoracotomy, intercostals ports, or under the sub-xiphoid process. Access to the atria is important for treatment of atrial fibrillation (AF), atrial-septal-defects (ASD&#39;s), patent foramen ovalis (PFO), and mitral or tricuspid valve disease. Also of importance is the elimination of the left atrial appendage volume at the end of the procedure in order to reduce stroke risk. Surgical removal and closure of the left atrial appendate has been accomplished by using a surgical stapler/ligation device or by suturing the appendage closed followed by surgical excision of the distal appendage. This is not without risks as noted by Krum et al. —David Krum, David L. Olson, Daniel Bloomgarden, Jasbir Sra, “Visualization of Remnants of the Left Atrial Appendage following Epicardial Surgical Removal,”  Heart Rhythm  (2004) 1, 249. Such surgical removal may result in an incomplete reduction of the left atrial appendage and allow a volume to remain unclosed, which is herein incorporated by reference in its entirety. 
     Regarding the relationship between the left atrial appendage and stroke risk, Blackshear et al. stated that left atrial appendage obliteration “is a routine part of modern ‘curative’ operations for nonrheumatic atrial fibrillation, such as the maze and corridor procedures.” Joseph L. Blackshear, MD, John A. Odell, FRCS (Ed), “Appendage Obliteration to Reduce Stroke in Cardiac Surgical Patients with Atrial Fibrillation,”  Ann. Thorac. Surg.,  1996; 61:755-759, which is herein incorporated by reference in its entirety. To assess the potential of left atrial appendage obliteration to prevent stroke in nonrheumatic atrial fibrillation patients, they reviewed previous reports that identified the etiology of atrial fibrillation and evaluated the presence and location of left atrial thrombus by transesophageal echocardiography, autopsy, or operation. 
     They reviewed the results of twenty-three separate studies and found that 446 of 3,504 (13%) rheumatic atrial fibrillation patients, and 222 of 1,288 (17%) nonrheumatic atrial fibrillation patients had a documented left atrial thrombus. Anticoagulation status was variable and not controlled for. Thrombi were localized to, or were present in the left atrial appendage and extended into the left atrial cavity in 254 of 446 (57%) of patients with rheumatic atrial fibrillation. In contrast, 201 of 222 (91%) of nonrheumatic atrial fibrillation-related left atrial thrombi were isolated to, or originated in the left atrial appendage (p&lt;0.0001). Their data suggested that left atrial appendage obliteration is a strategy of potential value for stroke prophylaxis in nonrheumatic atrial fibrillation. A device was developed that allows percutaneous left atrial appendage transcatheter occlusion (PLAATO) via transseptal catheterization. Initial studies in dogs demonstrated the ability of the device to seal the left atrial appendage. Sievert et al. reported their initial experience with PLAATO in a human clinical trial involving 15 patients. Horst Sievert, MD et al, “Percutaneous Left Atrial Appendage Transcatheter Occlusion to Prevent Stroke in High-Risk Patients with Atrial Fibrillation,”  Circulation,  2002, 105:1887, which is herein incorporated by reference in its entirety. 
     PLAATO was purported to be a less invasive, percutaneous approach to closing the left atrial appendage. Previous animal studies of the device with follow-up of up to 1 year have demonstrated occlusion of the left atrial appendage with complete healing, absence of erosions, new thrombus formation on the device, or interference with atrial function. 
     In the initial cohort of 15 patients, occlusion of the left atrial appendage was successful in all, as proven by left atrial angiography. There were no complications associated with the device, either acutely during the implantation procedure or during follow-up. The only complication during the study was hemopericardium in the first patient attempted, which was not device-related. It resulted from left atrial appendage access, and should be easily avoided with increased experience. The procedure was successful in a second attempt in that patient. 
     All patients did well in follow-up. One theoretical concern is the development of new thrombi on the implant. However, the use of ePTFE on the implant surface should result in relatively benign healing. Histological examination in dogs undergoing PLAATO reveal partial endothelialization at 1 month, which is complete by 2 to 3 months. In these 15 patients, transesophageal echo (TEE) at 1 month showed the surface to be completely smooth and free of mobile thrombi.  FIG. 35  illustrates a deployed PLAATO device. Fluoroscopic images of non-occluded left atrial appendage, deployment of the PLAATO device, and left atrial appendage post-deployment can be taken. 
     A larger cohort of patients was included in the European PLAATO Registry Trial by Fischer, et al. a study that was finished in January 2003 that examined the safety and feasibility of this procedure. This study described the experience of 92 patients. Inclusion criteria were atrial fibrillation (AF) with inability to take Warfarin®, prior cerebral ischemia and/or two clinical risk factors for stroke. After implantation of the PLAATO occluder, the patients were followed with X-ray, TEE and NIH stroke scale in regular intervals. Of the 92 patients, 67% were male with a mean age of 70±9 years. All candidates were successfully implanted. The mean procedure time was 76±36 minutes and the mean left atrial appendage orifice diameter was 20±3 mm. During follow up, one patient died of a bronchial carcinoma diagnosed 3 months before the one year follow up. One patient sustained a stroke six months post implant. Thus, the yearly incidence of stroke after implantation is 1.9%. With this small number of patients, the estimated risk reduction was 55%. 
     Of concern, in three patients, a thrombus on the occluder was found prior to hospital discharge (2) and one month after the procedure (1). All thrombi were resolved without sequelae. One device was chosen too small and embolized into the aorta after its release. It was snared with a catheter and was retrieved successfully. Another device was implanted successfully in the very same procedure. 
     To summarize this group&#39;s experience with the PLAATO device, the incidence of stroke in high-risk patients may decrease after implantation of the device. Considerable risks exist with this procedure, including errant transseptal puncture resulting in aortic dissection or atrial free wall perforation resulting in tamponade, embolization of the PLAATO device resulting in device entanglement in cardiac structures, along with thrombus formation on the occluder surface that could lead to emboli production and stroke. In addition, the chronic nature of this implant must be considered. Constant flexture of the nitinol wire structure may lead to long term fatigue and potential fracture and perforation of cardiac or adjoining tissues. 
     The group of Odell et al, hypothesized that if the atrial appendage could be safely obliterated, then the incidence of embolic stroke may be lessened. John A. Odell, et al., “Thoracoscopic Obliteration of the Left Atrial Appendage: Potential for Stroke Reduction,”  Ann. Thorac. Surg.,  1996, 61:565-569, which is herein incorporated by reference in its entirety. If the appendage can be obliterated using a thoracoscopic technique, a procedure of lesser magnitude than thoracotomy, then it may offer an alternative form of management for patients ineligible for Warfarin® therapy. To determine the feasibility of atrial appendage obliteration done using the thoracoscope, they performed the procedure in mongrel dogs and in human cadavers. 
     Transesophageal echocardiography with emphasis on visualization of the left atrial appendage was performed pre-, intra-, and postoperatively. In five dogs, the atrial appendage was obliterated with staples, and in five the appendage was obliterated with an endoloop of 0 Vicryl suture material. Three ports were made—one in approximately the seventh interspace approximately 5 cm from the midsternum (port 1), a second inserted anteriorly in the fourth interspace (port 2), and a third more posteriorly in the fourth interspace (port 3). Carbon dioxide was instilled to a pressure of 4 to 10 mm to collapse the lung. In all animals, the pericardium was opened anterior and parallel to the phrenic nerve. Gordon N. Olinger, MD, “Carbon dioxide displacement of left heart chambers,”  J. Thorac. Cardiovasc. Surg.,  1995, 109:187-188, which is herein incorporated by reference in its entirety. 
     Through the first port, the camera was inserted; through the second port, the pericardium was grasped with an instrument; and, using scissors inserted through the third port, the pericardium was opened. The technique then varied depending upon whether the appendage was obliterated with staples or with the endoloop. In those having the appendage stapled, the camera was withdrawn from port 1 and inserted in port 3. Through port 1, a 35 endo GIA stapler (Ethicon Endosurgery, Cincinnati, Ohio) with the knife blade removed was inserted, positioned across the base of the atrial appendage, and fired. In dogs having the appendage obliterated with the endoloop (Ethicon), the camera position was not changed. The endoloop was introduced through port 3 and the appendage was grasped through the loop of the suture. The loop was positioned across the base of the appendage and then tightened. 
     At 11 weeks, the dogs were again anesthetized with sodium pentobarbital (30 mg/kg intravenously) and a midline sternotomy was made. The heart was examined using epicardial echocardiography. The dogs were euthanized, the hearts were removed, and the left atrium was inspected. 
     The procedure also was attempted in eight human cadavers. In the cadavers, three ports were used for access. The most appropriate sites appeared to be the second interspace anteriorly in the midclavicular line (for grasping the pericardium and the atrial appendage), the sixth interspace in the midclavicular line (for the camera or stapling instrument), and the fifth interspace in the anterior axillary line (usually for the scissors to open the pericardium, but also for the camera or for the stapling instrument). The procedure as performed in the dog and human experiments is illustrated in  FIGS. 36A-E . 
     The group of DiSesa investigated the use of an automatic surgical stapler for ligation of the atrial appendage in sheep, and then applied this technique in patients. V. J. DiSesa, S. Tam and L. H. Cohn, “Ligation of the Left Atrial Appendage using an Automatic Surgical Stapler,”  The Annals of Thoracic Surgery , Vol. 46, 652-653, which is herein incorporated by reference in its entirety. Fourteen adult sheep underwent ligation of the left atrial appendage using a surgical stapler with a rotating head and either absorbable or stainless steel staples. In four sheep, killed after two hours, no hemorrhage or intra-atrial thrombus was observed acutely. Ten sheep were allowed to recover for 90 to 100 days, twice the expected absorption time of absorbable staples. There was complete obliteration of the left atrial appendage without evidence of intra-atrial thrombus or staple migration. The absorbable staples were completely reabsorbed. They subsequently used this technique in five patients undergoing mitral valve procedures. There were no complications, and adequate obliteration of the atrial appendage was achieved. Other reports indicate that staples may require the use of reinforcement strips to prevent bleeding and tissue tearing. 
     Considering the simple surgical ligation methods, the group of Katz, et al. studied the incidence of incomplete ligation of the left atrial appendage during mitral valve surgery. Edward S. Katz MD, FACC, Theofanis Tsiamtsiouris MD, Robert M. Applebaum MD, FACC, Arthur Schwartzbard MD, FACC, Paul A. Tunick MD, FACC and Itzhak Kronzon MD, FACC, “Surgical Left Atrial Appendage Ligation is Frequently Incomplete: A Transesophageal Echocardiographic Study,”  Journal of the American College of Cardiology , Volume 36, Issue 2, 1 Aug. 2000, Pages 468-471, which is herein incorporated by reference in its entirety. Using transesophageal Doppler echocardiography, they studied  50  patients who underwent mitral valve surgery and ligation of the left atrial appendage. Incomplete left atrial appendage ligation was detected in 18 of 50 (36%) patients. This study demonstrated that surgical left atrial appendage ligation is frequently incomplete. Residual communication between the incompletely ligated appendage and the left atrial body may produce a milieu of stagnant blood flow within the appendage and be a potential mechanism for embolic events. Ligation of the left atrial appendage is frequently performed during mitral valve surgery to eliminate a potential source of emboli. However, the success of completely excluding the left atrial appendage from the circulation had not previously been systematically addressed. Transesophageal echocardiography offers unique visualization of the appendage in the beating heart and can evaluate the integrity of the surgical ligation. Usually, when the left atrial appendage is ligated, its cavity is obliterated with clot (since no flow enters the cavity) and cannot be seen during echocardiography. This appearance was the same whether the patient was studied in the operating room or months after the surgery. When the appendage is incompletely ligated, not only can the appendage cavity be visualized but flow can be seen within the appendage, as well as through an opening in the ligation site. 
     The group discovered that 36% of the time the left atrial appendage was found to be incompletely ligated after attempts at excluding it from the left atrial body. Factors, such as an enlarged left atrium or significant mitral regurgitation, which may be thought to increase left atrial tension and pressure (perhaps predisposing to incomplete ligation or dehiscence of sutures), did not appear to correlate with this finding. They also did not observe a correlation between appendage size and the incidence of incomplete ligation. In addition, the surgical procedure (mitral repair or replacement) and operative approach (traditional sternotomy or minimally invasive approach) did not change the incidence of incomplete ligation. It is possible, however, that the sample size in this report may have been too small to exclude a significant effect of these variables on the development of incomplete left atrial ligation. 
     Incomplete left atrial appendage ligation was as commonly seen in the operating room, evaluating the patient by transesophageal echocardiography immediately after terminating cardiopulmonary bypass, as it was seen in the laboratory evaluating patients referred for transesophageal echocardiography at various times after the surgery. This suggested that incomplete left atrial appendage ligation is not a degenerative process with suture dehiscence over time, but rather is present immediately after the initial surgery. Incomplete ligation may be secondary to several surgical factors. First, the running sutures used may not start and end exactly at the most distal edges of the atrial appendage, which may not be recognized with the appendage empty and unstretched while on cardiopulmonary bypass during surgery. In addition, caution must be taken during appendage ligation to avoid deep suture bites, which may involve the left circumflex coronary artery or its branches that may course in the area. This meticulous care may lead to shallower suture bites that may dehisce when the LA is once again filled and stretched after cardiopulmonary bypass. Both of these mechanisms may play a role, as in many cases flow was detected both at the edge of the appendage orifice (apparently around the end of the suturing line) and through an area at the midpoint of the appendage orifice (through the suture line). One group reported six cases of incomplete left atrial appendage ligation when a purse string suture was used to accomplish the ligation, a technique different from that used by surgeons. The actual incidence, however, of incomplete left atrial appendage ligation using their technique was not addressed. 
     The clinical significance of an incompletely ligated left atrial appendage has never been studied. Theoretically, creating a small communication between the LA and left atrial appendage may produce stagnation of low velocity blood flow within the atrial appendage. The appendage would then be a model for thrombus formation and continue to serve as a potential source of embolization since a port of entry into the systemic circulation still exists. Although the numbers in this study were small, several observations support this theory. First, spontaneous echo contrast (a marker for stagnant blood flow and a precursor of thrombus formation) was seen within the appendage in half of the patients with incomplete ligation. Second, and perhaps more importantly, in two-thirds of patients with spontaneous echo contrast within the incompletely ligated appendage, the contrast was actually denser within the appendage than within the left atrial body, suggesting a more stagnant and thrombogenic milieu. In two patients, frank thrombus was seen within the incompletely ligated appendage. 
     The ultimate question, however, is whether patients with incompletely ligated left atrial appendages will have a higher incidence of thromboembolic events. In the Katz study, four patients with incompletely ligated appendages had such events (one patient with Starr-Edwards prosthesis, two with St. Jude prosthesis and one patient status after mitral repair). This is quite a high number considering that only eight patients with incomplete ligation had any potential for long term follow-up (the other ten patients with incomplete ligation were discovered in the operating room). However, one cannot exclude other etiologies for embolization (as mechanical prostheses or atrial fibrillation) and referral bias still clouds this issue. Certainly, conventional ligation methods must be questioned in light of the findings of this study. 
     A number of devices for occlusion of ASD&#39;s have been investigated. Melhem J. A. Sharafuddin, MD; Xiaoping Gu, MD; Jack L. Titus, MD, PhD; Myra Urness, BS; J. J. Cervera-Ceballos, MD; Kurt Amplatz, MD, “Preliminary Results With a New Self-Expanding Nitinol Prosthesis in a Swine Model Transvenous Closure of Secundum Atrial Septal Defects,”  Circulation,  1997, 95:2162-2168, which is herein incorporated by reference in its entirety. Most of these concepts involve percutaneous delivery from femoral vein access. Varying levels of success have been achieved. Device dislodgment can occur if the size of the defect greatly exceeds the waist diameter of the device or approaches the diameter of the retention buttons. On the other hand, placement of a disproportionately large device may result in mushrooming of the retention buttons and weakening of the cross-clamping forces against the septal rim, which increases the risk of blood flow behind the discs and may result in incomplete endothelialization. In addition, follow-up studies of a clamshell occlusion device reported a delayed rate of metal fatigue fractures of one or more arms of about 30%. The Amplatzer device is shown in  FIGS. 37A-E . 
     A small introduction system, simple and reliable placement technique, and favorable initial experimental success may provide promising potential of such a device for the percutaneous closure of secundum ASDs in all age groups. Heparinization is advocated in clinical use to lower the risk of catastrophic systemic embolization. 
     ASD device thrombosis is likely to be similar to thrombosis to be expected on left atrial appendage closure devices. This makes the study by Krumsdorf et al, on the incidence, morphology, and clinical course of thrombus formation after catheter closure of ASD closure devices of interest regarding devices such as PLAATO. Krumsdorf U, Ostermayer S, Billinger K, Trepels T, Zadan E, Horvath K, Sievert H, “Incidence and Clinical Course of Thrombus Formation on Atrial Septal Defect and Patient Foramen Ovale Closure Devices in 1,000 Consecutive Patients,”  J. Am. Coll. Cardio., Jan.  21, 2004. 43(2):302-9, which is herein incorporated by reference in its entirety. 
     A total of 1,000 consecutive patients were investigated after patent foramen ovale (PFO) (n=593) or atrial septal defect (ASD) (n=407) closure. Transesophageal echocardiography (TEE) was scheduled after four weeks and six months. Additional TEEs were performed as clinically indicated. Thrombus formation in the left atrium (n=11), right atrium (n=6), or both (n=3) was found in 5 of the 407 (1.2%) ASD patients and in 15 of the 593 (2.5%) PFO patients (p=NS). The thrombus was diagnosed in 14 of 20 patients after four weeks and in 6 of 20 patients later on. The incidence was: 7.1% in the CardioSEAL device (NMT Medical, Boston, Mass.); 5.7% in the StarFLEX device (NMT Medical); 6.6% in the PFO-Star device (Applied Biometrics Inc., Burnsville, Minn.); 3.6% in the ASDOS device (Dr. Ing, Osypka Corp., Grenzach-Wyhlen, Germany); 0.8% in the Helex device (W.L. Gore and Associates, Flagstaff, Ariz.); and 0% in the Amplatzer device (AGA Medical Corp., Golden Valley, Minn.). The difference between the Amplatzer device on one hand and the CardioSEAL device, the StarFLEX device, and the PFO-Star device on the other hand was significant (p&lt;0.05). For a device such as PLAATO, specifically designed to reduce or eliminate thromboembolic events coming from the region of the implant, occurrence of thrombus on ASD devices is a concern. 
     A method and apparatus for thoracoscopic intracardiac procedures was described U.S. Pat. No. 6,401,720, entitled “Method and Apparatus for Thoracoscopic Intracardiac Procedures,” Stevens, John H.; Palo Alto, Calif. 94303, Reitz, Bruce A.; Stanford, Calif. 94305, Roth, Alex T.; Redwood City, Calif. 94061, Peters, William S.; Woodside, Calif. 94062, Gifford, Hanson S.; Woodside, Calif. 94062, which is herein incorporated by reference in its entirety. They described devices, systems, and methods provided for accessing the interior of the heart and performing procedures therein while the heart is beating. In one embodiment, a tubular access device having an inner lumen is provided for positioning through a penetration in a muscular wall of the heart, the access device having a means for sealing within the penetration to inhibit leakage of blood through the penetration. The sealing means may comprise a balloon or flange on the access device, or a suture placed in the heart wall to gather the heart tissue against the access device. An obturator is removably positionable in the inner lumen of the access device, the obturator having a cutting means at its distal end for penetrating the muscular wall of the heart. The access device is preferably positioned through an intercostal space and through the muscular wall of the heart. Elongated instruments may be introduced through the tubular access device into an interior chamber of the heart to perform procedures, such as septal defect repair and electrophysiological mapping and ablation. A method of septal defect repair includes positioning a tubular access device percutaneously through an intercostal space and through a penetration in a muscular wall of the heart, passing one or more instruments through an inner lumen of the tubular access device into an interior chamber of the heart, and using the instruments to close the septal defect. Devices and methods for closing the septal defect with either sutures or with patch-type devices are disclosed. While this concept allows access to the heart chambers similar to the present invention, it does not provide for a simple means of incisional closure as do some embodiments of the invention. 
     Some embodiments of the invention may provide any one or more of the following advantages: a single point of access for surgical treatment of atrial fibrillation; fewer inter-costal access ports may be needed for treating atrial fibrillation, as opposed to existing minimally-invasive methods; blunt dissection of cardiac tissue is generally not required; pericardium is left substantially intact, except for a small incision; access to the heart for delivery of therapies for various disease states; a single device can provide surgical access to the heart chambers, as well as providing a means of closing the point of access at the end of the procedure; and the left atrial appendage can be ligated and/or eliminated at the close of the procedure with little or no risk of tearing. The left atrial appendage can be eliminated at the close of the procedure such that a residual remaining volume which could lead to strokes is avoided. 
     Some embodiments of the invention provide a device that can provide access to the interior of the heart chambers. The device can allow for single point access to treat atrial fibrillation, atrial-septal defects, patent foramen ovalis, and valvular disease, as well as other arrhythmias. Some embodiments of the device can be used to access the ventricles from the access achieved through either appendage. Ventricular septal defects can be addressed. The device can be applied to other body structures, such as the stomach where a portion of the stomach wall could be ligated by the elastic band and excluded. This may be suitable as a treatment for obesity. 
     Some embodiments of the invention provide methods and devices to allow entry into the atria of a beating heart to perform delivery of therapy to the structures within the heart and endocardial surfaces and valves associated with the heart chambers. Upon removal of the device from the appendage, a permanent closure and elimination of the appendage volume can be affected. More specifically, the entry points can be located in the left and right atrial appendages. Of these, the left atrial appendage may be most appropriate, because closure and elimination of this appendage following a procedure has become a standard surgical practice performed by many surgeons. 
     According to embodiments of the method of the invention, pre-procedure includes placement of one or two chest wall access ports for visualization and placement of the invention. The lung can be deflated and a small opening in the pericardium can be made adjacent to the left atrial appendage.  FIG. 38  schematically illustrates the relative locations of structures of the heart and chest of interest regarding the invention. More specifically, the left atrial appendage is shown in a stretched state without the pericardium in place. The heart structures noted on  FIG. 38  include the following: SVC—superior vena cava, IVC—inferior vena cava, TV—tricuspid valve, FO—fossa ovalis, MV—mitral valve, PV—pulmonary vein, and left atrial appendage—left atrial appendage.  FIGS. 39-68  illustrate devices and methods of using the devices according to various embodiments of the invention. In some embodiments, a device  400  can include an elastic cinch ring  410 , ring expansion arms  412 , and a portal tube assembly  414 . The ring expansion or cinch ring support arms  412  can include three or four arms. The device  400  can be positioned through a chest port  416  in a portion of the chest wall  418 . The device  400  can be passed through a chest port  416  placed between the ribs. The anatomical drawings of  FIGS. 39-57  have been simplified to show only the left atrial appendage and the chest wall. 
       FIG. 39  illustrates the elastic cinch ring  410  in a contracted state.  FIG. 40  illustrates the device  400  being advanced toward the left atrial appendage.  FIG. 41  illustrates a suction cup or Babcock grasper probe  420  being advanced through the portal tube assembly  414 . 
       FIG. 42  illustrates the suction cup or Babcock grasper probe  420  being attached to an end of the left atrial appendage. In other embodiments, any suitable type of grasper, vacuum device, adhesive, cyrogenic device, or nanotechnology device can be used to grasp and pull the left atrial appendage.  FIG. 43  illustrates the support arms  412  being expanded and the left atrial appendage being pulled toward the portal tube assembly  414 .  FIG. 44  illustrates the cinch ring  410  being advanced over the left atrial appendage.  FIG. 45  illustrates the cinch ring  410  being positioned over the mid to proximal left atrial appendage. 
       FIG. 46  illustrates the cinch ring  410  being allowed to contract over left atrial appendage and occlude a lumen  422  of the left atrial appendage.  FIG. 47  illustrates the suction cup or Babcock grasper probe  420  removed from portal tube assembly  414 .  FIG. 48  illustrates a dilator/sheath assembly  424  including a dilator  426  and a sheath  428  being advanced through the portal tube assembly  414 . In some embodiments, prior to puncturing into the atrial appendage, the thoracic cavity can be inflated with carbon dioxide gas. Carbon dioxide inflation of the pericardial space can be used to lessen the prevalence and consequences of air embolism, can help limit the chances of air introduction, and can help limit bleeding.  FIG. 49  illustrates a needle or sharp wire  430  being advanced through a lumen of the dilator  426  to puncture into the left atrial appendage lumen  422 . 
       FIG. 50  illustrates the dilator  426  being advanced into the lumen  422  of the left atrial appendage and the needle  430  retracted.  FIG. 50  illustrates the sheath  428  being advanced over the dilator  426  into the left atrial appendage lumen  422 .  FIG. 51  illustrates the left atrial appendage being filled with heparinized saline, as blood and air are removed. As shown in  FIG. 52 , the left atrial appendage lumen  422  can be aspirated of blood  432  and flushed with heparinized saline using a syringe  434  to prevent thrombus formation. As shown in  FIG. 53 , the left atrial appendage lumen  422  can be filled with heparinized saline as blood and air are removed. However, in some embodiments, it may be desirable to allow blood to form a thrombus in the remaining left atrial appendage volume to promote healing and absorption of the closed-off portion of the left atrial appendage by surrounding tissue. 
     As shown in  FIG. 54 , the dilator  426  can be advanced past the cinch ring  410  and into the left atrium. As shown in  FIG. 55 , the sheath  428  can be advanced over the dilator  426  past the cinch ring  410  and into the left atrium. As shown in  FIG. 56 , the dilator  426  can be removed. A hemostasis valve (not shown) can be positioned on a proximal end of the sheath. As shown in  FIG. 57 , therapeutic implements can be advanced into the left atrium for the treatment of various conditions. 
       FIG. 58  illustrates one embodiment of a balloon ablation device  436  positioned at the right inferior pulmonary vein ostium. The use of a cryogenic or high-intensity focused ultrasound balloon ablation device can be used in some embodiments of the invention.  FIG. 59  illustrates one embodiment of a balloon ablation device  436  positioned at the left superior pulmonary vein ostium. 
       FIG. 60  illustrates one embodiment of an encircling ablation device  438  approaching the left superior pulmonary vein ostium. The ablation device  438  can use radiofrequency (RF) energy, cryothermy, high-intensity focused ultrasound, microwaves, or any other suitable ablation energy.  FIG. 61  illustrates one embodiment of an encircling ablation device  438  placed around the left superior pulmonary vein ostium. 
       FIG. 62  illustrates one embodiment of a left atrial de-bulking spiral ablation device  440  placed against the posterior left atrium.  FIG. 63  illustrates one embodiment of a high intensity focused ultrasound ablation device  442  that can create a lesion over the left atrial isthmus.  FIG. 64  illustrates one embodiment of a PFO or ASD closure device  444  being deployed in the fossa ovalis of the inter-atrial septum.  FIG. 65  illustrates one embodiment of a linear ablation device  446  forming connecting lesions between the pulmonary veins. 
     As shown in  FIG. 66 , at the completion of all the endocardial therapeutic procedures, the elastic cinch ring  410  can be allowed to constrict down around the base of the left atrial appendage. The sutures or other devices holding the cinch ring  410  can be released such that the support arms  412  and the portal tube assembly  414  can be pulled away from the heart, while leaving the cinch ring  410  substantially permanently in place at the base of the appendage. As shown in  FIG. 67 , immediately following the procedure, the left atrial appendage will generally include a volume that is contained by the cinch ring  410 . Healing will then occur and the vestige of the left atrial appendage will be absorbed into the atrial wall. As shown in  FIG. 68 , after approximately 12 weeks, the left atrial appendage is expected to have been absorbed and assimilated by the atrial wall. The ring  410  can remain embedded in the remaining scar  448 . 
       FIGS. 69-71  illustrate a device  500  for ligation of an atrial appendage. The device  500  can include a ring applicator or delivery tool  502  and an occlusion member or ring  514 . In one embodiment, the occlusion ring  514  can be made of a 30 A durometer silicone rubber, although other hardnesses of silicone or other materials, such as polyurethane can be used. The ring  514  can be covered with a material such as Dacron® polyester to promote tissue ingrowth or prevent ring slippage after placement or to spread the load bearing surfaces of the ring. The ring  514  can be generally expandable for placement around the atrial appendage. The delivery tool  502  can be used to expand the ring  514 . The delivery tool  502  can include a shaft  520  and a handle  530  coupled to shaft  520 . The delivery tool  502  can be sized for reaching an atrial appendage through an opening in the patient&#39;s chest, for example, through a sternotomy or thoracotomy. The delivery tool  502  can include a tissue-grasping tool channel  570  extending from the handle  530  to the distal end of the shaft  520 . A tissue-grasping tool  580  may be movably positioned within tissue-grasping tool channel  570 . For example, shaft  584  of tissue-grasping tool  580  fits within tool channel  570 . In one embodiment, tissue-grasping tool  580  may include one or more hooks, barbs, suction ports and/or graspers. For example, as shown in  FIGS. 72 and 73 , tissue grasping tool  580  may include tissue graspers  582 . The tissue-grasping tool  580  can be used to grasp the atrial appendage and pull it through ring  514 . In one embodiment, the tissue-grasping tool  580  can be moved distally and/or proximally relative to shaft  520 . 
     In one embodiment, the delivery tool  502  can include a ring spreader  540  having a pair of ring-expanding members  542  used to hold and expand the ring  514 . The ring spreader  540  can be coupled to a distal end of shaft  520 . The ring  514  can be releasably coupled or attached to the distal ends of ring-expanding members  542  and the distal end of shaft  520 , for example, via one or more sutures  550 . The sutures  550  can loop around the ring  514 . The ends of the sutures  550  can pass through one or more lumens within the ring expanding members  542 , the shaft  520 , and the handle  530 . In one embodiment, the two ring-expanding members  542  open ring  514  into a triangular shape. The proximal ends of the ring-expanding members  542  are pivotally coupled to the distal end of shaft  520 , thereby allowing the ring-expanding members  542  to pivot from a closed or collapsed position, as shown in  FIG. 69 , to an open or extended position, as shown in  FIG. 70 . In the collapsed position, ring-expanding members  542  run parallel to shaft  520  and the distal ends of the ring-expanding members  542  point in a direction towards handle  530 . In the extended position, ring-members  542  are aligned perpendicular to each other and to shaft  520 . In the extended position, ring  514  has an open triangular configuration, as shown in  FIG. 70 . In one embodiment, sutures  550  are used to control the opening and closing of ring-expanding members  542 . Sutures  550  run through suture lumens  525  of shaft  520 . The proximal ends of sutures  550  are attached or coupled to suture tension knob or ring expansion mechanism  532  located at handle  530 . Suture tension knob  532  is rotatable and may include a ratcheting mechanism. The ratcheting mechanism may be used to keep tension on the sutures without having to continuously hold onto knob  532 . As knob  532  is rotated, sutures  550  stretch ring  514  toward the distal ends of ring-expanding members  542  and actuate ring-expanding members  542  to move from a collapsed configuration to an extended configuration wherein ring  514  is opened into a triangular configuration. Ring  514  may be released when desired, for example, around tissue via actuation of suture cutting mechanism  562 . Suture cutting mechanism  562  is used to cut sutures  550 , thereby releasing ring  514  from delivery tool  502  remotely. Suture cutting mechanism  562  includes cutting blade  564 , which is used to cut sutures  550 . 
     In one embodiment, shaft  520  is approximately 12 mm in diameter and tool channel  570  is approximately 5.5 mm in diameter. In one embodiment, tool channel  570  provides guidance for positioning and manipulating tissue-grasping tool  580 . In addition, tool channel  570  allows deliver tool  502  and tissue-grasping tool  580  to be positioned together through a single port, for example, a 12 mm port placed between the patient&#39;s ribs and it allows the two tools to be held by one hand. 
     In one embodiment of the present invention, the distal end of delivery tool  502  may be passed through a port or small incision, for example, in the chest of a patient and positioned adjacent the left atrial appendage of a heart. Next, knob  532  may be rotated, thereby opening ring  514 . A tissue-grasping tool  580  may then be slid distally along tissue-grasping tool channel  570  so that graspers  582  protrude through ring  514 . Graspers  582  may then be manipulated by handle  586  to grasp tissue of the left atrial appendage. Tissue-grasping tool  580  and delivery tool  502  are then manipulated so as to position a desired portion of the left atrial appendage within the triangular opening of ring  514 . Ring  514  is then released from delivery tool  502  and allowed to constrict tissue of the left atrium. 
     The ring or band occluders and the clip occluders disclosed herein can be constructed of any one or more of the following materials: silicone rubber, polyurethane, super-elastic material, shape-memory polymer or metal, latex, nitrile, butyl, styrene-butadiene, polyacrylate, acrylic, polyisoprene, chloroprene, fluoroelastomers, or other suitable biocompatible elastomeric materials. The ring or band occluders and the clip occluders disclosed herein can incorporate any one or more of the following features: texturing to aid in mechanical stability (i.e., ridges, bumps, grooves, etc.); fabric such as Polyethyleneterapthalate (i.e., Dacron®), polyester, ePTFE, etc. to promote tissue ingrowth; other types of coatings to promote tissue ingrowth; and pharmacological agents (e.g. a controlled release agent) to aid in tissue ingrowth, local therapeutic apoptosis, local necrosis, revascularization, arrhythmia control, infection control, anti-bacterial, fluid balance (i.e., atrial natritic peptide replacement). 
     In some embodiments of the invention, the ring or band occluders and/or clip occluders may incorporate one or more pharmacological agents including anti-inflammatory agents (e.g., steroids, dexamethasone, beclomethasone) anti-arrhythmic agents, chemotherapeutic agents, anti-infection agents, anticoagulant agents, anti-thrombotic agents (e.g., coumadin, heparin), clotting agents, platelet agents, cytotoxic agents, growth factors, angiogenesis factors, hormones (e.g., atrial natriuretic peptide), nitric oxide, radioactive agents, radiopaque agents (e.g., barium sulfate), echogenic agents (e.g., perfluorocarbon), antibodies, antigens, immunoglobulins, enzymes, neurotransmitters, cytokines, blood agents, regulatory agents, transport agents, fibrous agents, proteins, peptides, proteoglycans, toxins, antibiotic agents, antibacterial agents, antimicrobial agents, bacterial agents, hyaluronic acid, polysaccharides, carbohydrates, fatty acids, catalysts, vitamins, DNA segments, RNA segments, nucleic acids, lectin, antiviral agents, viral agents, genetic agents, ligands, drugs and dyes (e.g., which act as biological ligands). One or more drugs or gents may be found in nature (naturally occurring) and/or may be chemically synthesized. 
     One or more drugs or agents may be incorporated into the ring, band or clip, e.g., within a polymeric material of the ring, band or clip. One or more drugs or agents may be incorporated into one or more coatings of the ring, band or clip, e.g., within a polymeric coating covering at least a portion of the ring, band or clip. One or more drugs or agents may be incorporated into one or more fabrics of the ring, band or clip, e.g., within or on a fabric coating covering at least a portion of the ring, band or clip. In some embodiments of the invention, one or more drugs or agents may be loaded uniformly throughout one or more materials of the ring, band or clip. In some embodiments of the invention, one or more drugs or agents may be loaded non-uniformly in one or more materials of the ring, band or clip. In some embodiments of the invention, one or more drugs or agents may be loaded within an inner circumference of the ring, band or clip. In some embodiments of the invention, one or more drugs or agents may be loaded within an outer circumference of the ring, band or clip. 
     In some embodiments of the invention, one or more materials incorporated into the ring, band or clip may be “smart materials” which may alter their structure in response to one or more external factors, e.g., temperature. For example, the application of heat may cause a material, e.g., a polymer, to change shape or conformation, thereby resulting in the release of a drug or agent. In one embodiment, ultrasound, e.g., focused ultrasound, may be used to create heat needed to cause the material change shape or conformation. 
     In some embodiments of the invention, the ring, band or clip may comprise one or more radiopaque materials, e.g., barium sulfate, thereby making the ring, band or clip observable during fluoroscopic procedures. In some embodiments of the invention, the ring, band or clip may comprise one or more echogenic materials, e.g., perfluorocarbon, thereby making the ring, band or clip observable during ultrasound procedures. 
     In some embodiments of the invention, the ring, band or clip may release one or more drugs or agents via a diffusion-controlled mechanism. For example, a drug or agent may be uniformly or non-uniformly dispersed or dissolved in a material, e.g., a polymeric material, of the ring, band or clip and/or a coating of the ring, band or clip and/or a fabric covering of the ring, band or clip. The drug or agent may diffuse from an area of high concentration (e.g., from the material(s) of the band or clip) to an area of low concentration (e.g., an area of tissue such as the LAA). 
     In some embodiments of the invention, the ring, band or clip may release one or more drugs or agents via a biodegradable mechanism. For example, a drug or agent may be uniformly or non-uniformly dispersed or dissolved in a material, e.g., a polymeric material, of the ring, band or clip and/or a coating of the ring, band or clip and/or a fabric covering of the ring, band or clip. The drug or agent may be released during degradation of the material. The material may be designed to either degrade completely or to degrade partially, e.g., leaving the core structure of the material intact. 
     In some embodiments of the invention, the ring, band or dip may comprise a cross-sectional shape that may be round, square, rectangular, oval, triangular, star-shaped, etc. In some embodiments of the invention, the ring, band or clip may be reversibly placed, and its position may be adjusted if necessary. In some embodiments of the invention, multiple ring, band or clip may be placed more and more proximal to the base of the left atrial appendage. 
     In some embodiments of the invention, the ring, band or clip may include one or more sensors, for example to monitor changes in one or more tissue properties. One or more properties of surrounding tissue may change over time and/or in response to drug delivery, as described above, for example. In one embodiment, the band or clip may include a sensing electrode. Sensors may be monitored and/or controlled via wireless telemetry, for example, thereby providing wireless monitoring of one or more tissue properties over time. 
     In one embodiment, one or more sensors may comprise a biosensor, for example, comprising an immobilized biocatalyst, enzyme, immunoglobulin, bacterial, mammalian or plant tissue, cell and/or subcellular fraction of a cell. For example, the tip of a biosensor may comprise a mitochondrial fraction of a cell, thereby providing the sensor with a specific biocatalytic activity. In one embodiment, one or more sensors may be based on potentiometric technology or fiber optic technology. For example, a sensor may comprise a potentiometric or fiber optic transducer. An optical sensor may be based on either an absorbance or fluorescence measurement and may include an UV, a visible or an IR light source. In one embodiment, one or more sensors may be used to detect naturally detectable properties representative of one or more characteristics, e.g., chemical, physical or physiological, of a patient&#39;s bodily tissues or fluids. For example, naturally detectable properties of patient&#39;s bodily tissues or fluids may include pH, fluid flow, electrical current, impedance, temperature, pressure, components of metabolic processes, chemical concentrations, for example, the absence or presence of specific peptides, proteins, enzymes, gases, ions, etc. In one embodiment, one or more sensors may include one or more imaging systems, camera systems operating in UV, visible, or IR range; electrical sensors; voltage sensors; current sensors; piezoelectric sensors; electromagnetic interference (EMI) sensors; photographic plates, polymer-metal sensors; charge-coupled devices (CCDs); photo diode arrays; chemical sensors, electrochemical sensors; pressure sensors, vibration sensors, sound wave sensors; magnetic sensors; UV light sensors; visible light sensors; IR light sensors; radiation sensors; flow sensors; temperature sensors; or any other appropriate or suitable sensor. In one embodiment, one or more sensors may be powered by a suitable power source. In addition, one or more sensors may be coupled to any appropriate output device, for example, a LCD or CRT monitor which receives and displays information regarding one or more sensors. 
     A temperature sensor may incorporate one or more temperature-sensing elements such as, for example, thermocouples, thermisters, temperature-sensing liquid crystals, or temperature-sensing chemicals. A temperature sensor could be used, for example, to monitor tissue temperature. 
     The signals from one or more sensor may be amplified by a suitable amplifier before reaching an output device. The amplifier also may be incorporated into an output device. Alternatively, the amplifier may be a separate device. The output device may incorporate one or more processors. In one embodiment, sensors may be positioned around a perimeter of the band or clip. When sensed tissue reaches a perimeter, a corresponding sensor may send a signal. In one embodiment, a sensor may send constant signals. For example, a sensor may send a constant signal based on its voltage. As a tissue perimeter changes, the voltage of the sensor may change proportionately and the signal sent by the sensor may change proportionately. 
       FIGS. 74 and 75  illustrate one embodiment of device  200  for ligation of an atrial appendage. In this embodiment, device  200  includes a ring applicator or delivery tool  202  and an occlusion member or ring  214 . The delivery tool  202  can include a ring spreader  240  having ring-expanding members  242  used to hold and expand the ring  214 . The ring spreader  240  can be coupled to a distal end of shaft  220 . In one embodiment, the delivery tool  202  can include three ring-expanding members  242 . As shown in  FIG. 76 , the ring  214  can be releasably coupled or attached to the distal end of ring-expanding members  242 , for example, via wire hooks  272  made of stainless steel or nitinol, for example. The wire hooks  272  may be passed through one or more lumens  278  within ring-expanding members  242 . The wire hooks  272  may be retracted partially (as shown in  FIGS. 77 and 78 ) or completely into ring-expanding members  242  via a ring release mechanism  273  located at the proximal end of device  20 , thereby releasing ring  214  from delivery tool  202 . The handle  230  may also include a ring expansion mechanism  260  used to control the expansion of the ring  214 . In one embodiment, ring expansion mechanism  260  is coupled to a wedge member  274  via a shaft  275 . As the wedge member  274  is moved via ring expansion mechanism  260  from a distal position to a more proximal position the ring expanding members  242  are forced to move from a closed or collapsed configuration to an open or expanded configuration, as shown in  FIGS. 74 and 75 . 
       FIG. 79  illustrates one embodiment of device  200  for ligation of an atrial appendage. In this embodiment, device  200  includes a ring applicator or delivery tool  202  and an occlusion member or ring  214 . The delivery tool  202  can include a ring spreader  240  having ring-expanding members  242  used to hold and expand the ring  214 . The ring spreader  240  can be coupled to a distal end of shaft  220 . In one embodiment, the delivery tool  202  can include three ring-expanding members  242  pivotally coupled to distal end of shaft  220 , as shown in  FIG. 80 . As shown in  FIG. 81 , the ring  214  can be releasably coupled to the distal end of ring-expanding members  242 , for example, via ring attachment members  252  pivotally coupled to ring expanding members  242 . In one embodiment, ring attachment members  252  may be remotely controlled to pivot thereby releasing ring  214  from delivery tool  202 . A ring release mechanism  273 , coupled to ring attachment members  252 , may be located at or near handle  230 . Ring release mechanism  273  may be used to control the pivoting of ring attachment members  252  thereby releasing ring  214  from delivery tool  202 . The handle  230  may also include a ring expansion mechanism  260  used to control the expansion of the ring  214 . The ring expansion mechanism  260  may be coupled to the ring-expanding members  242 . The ring expansion mechanism  260  can control movement of the ring expanding members  242  from a closed or collapsed configuration to an open or expanded configuration, as shown in  FIGS. 79 and 80 . 
       FIG. 82  illustrates one embodiment of device  34  for ligation of an atrial appendage, wherein ring applicator  34  includes a shaft  36  with a handle  38  on a proximal end and a ring spreader  40  on a distal end. In one embodiment, the ring spreader  40  includes a pair of spreader jaws  42  and  44 . In one embodiment, a spring member may bias the jaws into an open or expanded configuration and/or a closed or collapsed configuration. In an alternative embodiment, the jaw arms  42  and  44  may ride on a cylinder  51  which forces the arms apart when they are pushed forward out the distal end of shaft  36 .  FIG. 83  shows one embodiment of ring spreader  40  in a closed or collapsed configuration.  FIG. 84  shows one embodiment of ring spreader  40  in an open or expanded configuration. In one embodiment, a jaw actuator  48  is moveably coupled to handle  38 . The jaw actuator  48  includes a shaft  49  connected to jaws  42  and  44 . When the shaft  49  is pushed forward within the shaft  36 , jaws  42  and  44  are forced out the distal end of shaft  36  and into an open or expanded configuration. In some embodiments, as shown in  FIG. 9B , the ring  16  can be removably attached to the ring spreader  40  by one or more sutures, which may act as a retainer to hold the ring  16  in the ring spreader  40 . 
     In some embodiments, the shaft of the ring, band or clip delivery tool may comprise one or more flexible, bendable and/or articulation section and/or sections. One or more flexible, bendable and/or articulation section and/or sections of the shaft of the delivery tool allows the device to accommodate a variety of patient anatomies via flexing, bending and/or articulation of the delivery tool&#39;s shaft. Preferably, any flexing, bending and/or articulation of the shaft will not inhibit the opening and closing mechanism of the delivery tool for opening and closing the ring, band or clip. 
     In one embodiment, as shown in  FIG. 85 , a portion of the shaft of the delivery tool may comprise an outer tube member  110  made of a memory alloy and/or plastic which may be pre-bent to a desired angle, for example 90°. The shaft may then comprise an inner stiffening rod member  111  placed within a lumen  112  of the outer tube member  110 . The inner stiffening rod member  111  may be used to straighten the outer tube if advanced within the lumen  112  of the outer tube member  110  and allow the outer tube member  110  to return to its pre-bent shape if retracted. In one embodiment, the stiffening rod member  111  may be controlled by a rotating collar axially located with the outer tube member  110  and stiffening rod member  111 . In one embodiment, the shaft or outer tube member  110  may include one or more lumens for control lines that facilitate the opening and closing mechanism or ring spreader of the delivery tool for opening and closing the ring, band or clip. 
     In one embodiment, as shown in  FIGS. 86 and 87 , a portion of the shaft of the delivery tool may comprise on or more hinge mechanisms  310 , e.g., a hinge mechanism comprising multiple living hinges along a shaft section to create a gradual bend or curve for articulation. In one embodiment, one or more lumens  311  for control lines that facilitate the opening and closing mechanism or ring spreader of the delivery tool may be located as close to or through the pivots  312  of the hinges, thereby insuring that the control lines would not substantially lengthen or shorten throughout the range of hinge articulation. A cable or rod may be used, for example, to operate the hinge mechanism  310 , thereby articulating the shaft portion comprising the living hinges, for example. One or more lumens  313  may be used for the cable or rod. The articulation of the hinge mechanism  310 , e.g., the pushing and pulling of the cable or rod, may be controlled by a rotating collar axially located with the shaft. A gradual bend curve formed from the multiple living hinges prevents sharp bends or kinking in the opening and closing mechanism control lines, thereby insuring good working conditions for the opening and closing mechanism. 
       FIG. 88  illustrates one embodiment of device  300  for ligation of an atrial appendage, wherein ring applicator  300  includes a shaft  36  with a handle or hand piece  38  on a proximal end and a ring spreader  40  on a distal end. Shaft  36  may include an articulation section  320 , for example, located at the distal portion of shaft  36 , see  FIG. 89 . In one embodiment, articulation section  320  of shaft  36  may include one or more hinge mechanisms as shown in  FIG. 90 . In one embodiment, hinge mechanism  325  includes multiple living hinges controlled via a hinge articulation control wire  330 . Moving control wire  330  in a proximal direction causes articulation section  320  to form a bend or curve. Moving control wire  330  in a distal direction causes articulation section  320  to straighten. In one embodiment, articulation control wire  330  is coupled to an articulation actuator or drive mechanism  335  positioned at the distal end of handle or hand piece  38 . In one embodiment, as shown in  FIGS. 91 ,  92  and  93 , articulation drive mechanism  335  comprises an articulation drive screw  340  and an articulation drive screw knob  345  used to manually control the movement of control wire  330  in both a distal direction and a proximal direction. Rotation of drive screw knob  345  causes drive screw  340  to rotate, which, in turn, causes control wire  330  to move distally or proximally, thereby causing the hinged section  320  to bend or straighten. 
     In one embodiment, as shown in  FIG. 90 , ring spreader  40  includes a ring spreader drive wire  350  used to expand at least one embodiment of ring  14 . For example, ring  14  may include a textile or fabric mesh covering  355  as shown in  FIGS. 94 and 95 . The fabric mesh covering  355  may cover the entire ring  14 . Spreader drive wire  350  may run through a mesh covering lumen  357  as shown in  FIG. 95 . In one embodiment, the distal end of spreader drive wire  350  is fixed in place within mesh covering lumen  357  so that as drive wire  350  is pushed distally into mesh covering lumen  357  the mesh covering expands. Expansion of the mesh covering  355  forces ring  14  to expand. When drive wire  350  is pulled back proximally, the mesh and band contract back to a pre-expanded configuration. In one embodiment, the ring and mesh covering are expanded via drive wire  350  and they are positioned on the left atrial appendage as desired. Drive wire  350  may then be pulled proximally out of the mesh, thereby causing the ring and mesh covering to contract around the atrial appendage. In an alternative embodiment, the ring and mesh covering are expanded via drive wire  350  and they are positioned on the left atrial appendage as desired. Drive wire  350  may then be pulled proximally, thereby causing the ring and mesh covering to contract around the atrial appendage. The drive wire and mesh covering may then be removed completely from the ring, for example, via a suture or running stitch  356 . The running stitch may be pulled out of the mesh covering thereby allowing the mesh covering to be removed from the ring. In one embodiment, as shown in  FIG. 95 , the running stitch may be located along the mesh covering and along the inside lumen of ring  14 . In some embodiments, drive wire  350  may be releasably coupled to ring  14  via a mesh covering, one or more sutures, and/or one or more wires, for example. 
     In one embodiment, as shown in  FIGS. 96 and 97 , ring spreader drive wire  350  is coupled to a ring spreader actuator or drive mechanism  360  positioned at the proximal end of handle or hand piece  38 . In one embodiment, ring spreader drive mechanism  360  comprises a hand trigger mechanism  365  used to manually control the movement of ring spreader drive wire  350  in both a distal direction and a proximal direction, thereby controlling the expansion and contraction of ring  14 . As shown in  FIG. 97 , ring spreader drive mechanism  360  may also comprise a drive wire release assembly  370 . Drive wire release assembly  370  allows the ring spreader drive wire  350  to be released from ring spreader drive mechanism  360 . Drive wire release assembly  370  may comprise a spring  372 . Spring  372  may be used to provide a desired amount of force or tension on drive wire  350 . Drive wire release assembly  370  may comprise a drive wire release member  374 . In one embodiment, drive wire release member  374  includes a release mechanism that is designed to release drive wire  350  when it is squeezed. In one embodiment, drive wire release assembly  370  includes locking pins  375 , drive shaft members  376  and  377  and plunger  378  and plunger shaft  379 . In one embodiment, as shown in  FIGS. 98A ,  98 B and  98 C, the drive wire release mechanism of drive wire release member  374  may comprise a coupler  380  coupled to drive wire  350  that when squeezed, opens a pair of jaws, which allows the user to pull the coupler free from the rest of the device. 
     Furthermore, other substitutions, modifications, changes, and omissions may be made in the design, operating conditions, and arrangements of the exemplary embodiments without departing from the scope of the invention as expressed in the appended claims. In addition, it will be appreciated by those skilled in the art that while the invention has been described above in connection with particular embodiments and examples, the invention is not necessarily so limited, and that numerous other embodiments, examples, uses, modifications and departures from the embodiments, examples and uses are intended to be encompassed by the claims attached hereto. The entire disclosure of each patent and publication cited herein is incorporated by reference, as if each such patent or publication were individually incorporated by reference herein.

Technology Category: 1