Abstract:
Excessive dilation of the annulus of a mitral valve may lead to regurgitation of blood during ventricular contraction. This regurgitation may lead to a reduction in cardiac output. Disclosed are systems and methods relating to an implant configured for reshaping a mitral valve. The implant comprises a plurality of struts with anchors for tissue engagement. The implant is compressible to a first, reduced diameter for transluminal navigation and delivery to the left atrium of a heart. The implant may then expand to a second, enlarged diameter to embed its anchors to the tissue surrounding and/or including the mitral valve. The implant may then contract to a third, intermediate diameter, pulling the tissue radially inwardly, thereby reducing the mitral valve and lessening any of the associated symptoms including mitral regurgitation.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application claims the priority benefit under 35 U.S.C. §119(e) of U.S. Provisional Application No. 62/025,967, filed Jul. 17, 2014, and U.S. Provisional Application No. 62/038,032, filed Aug. 15, 2014, the entireties of which are hereby incorporated by reference herein. 
    
    
     BACKGROUND 
     1. Field 
     The present application relates generally to treating heart disease, and more specifically, to methods and systems for an adjustable endolumenal mitral valve ring. 
     2. Description of Related Art 
     Heart disease can cause the chambers of the heart to expand and/or weaken. With specific reference to the mitral valve of the heart, when the left ventricle dilates, papillary muscles become displaced. When the mitral valve is incompetent due to heart disease, the mitral annulus (e.g., the annulus of the mitral valve) dilates excessively. In this state of dilation, the valve leaflets of the mitral valve no longer effectively close, or coapt, during systolic contraction. Consequently, regurgitation of blood occurs during ventricular contraction and cardiac output decreases. 
     This condition is typically addressed by open-heart surgical implantation of an annuloplasty ring. Typically, a surgeon positions an annuloplasty ring proximate to the mitral annulus and sutures it in place, thereby restoring the mitral valve to approximately its native circumference. If successful, the valve leaflets can then function normally again. 
     However, open-heart surgery is not without its shortcomings. Open heart-surgery is highly invasive and has many associated risks, including risks of infection, heart attack and/or stroke, memory loss, blood clots, blood loss, injury to the surrounding anatomy, and/or many other pains and/or discomforts. Accordingly, there is a need in the art for less invasive systems and methods for addressing heart valve incompetency of the mitral valve. 
     SUMMARY 
     The present disclosure includes methods and systems relating to reshaping a mitral valve using a laser-cut tubular implant having a plurality of struts with barbed anchors for tissue engagement. The implant may be compressible to a first, reduced diameter for transluminal navigation and delivery to the mitral valve treatment site. It may then be expandable to a second, enlarged diameter for engaging tissue surrounding and/or including the mitral valve (as used herein, the tissue surrounding and/or including the mitral valve includes the mitral annulus). Typically, the anchors of the implant embed into the tissue while the implant is in the enlarged state. The implant may then contract to a third, intermediate diameter, pulling the tissue of the mitral valve radially inward, which reduces the mitral valve. The reduction of the mitral valve may lessen any of the symptoms associated with excessive mitral valve dilation, including mitral regurgitation. Any or all of the expanding or contracting functions can be accomplished either actively or passively. 
     In some embodiments, the implant may be delivered to the tissue surrounding and/or including the mitral valve using a delivery system. The delivery system may comprise of a delivery catheter connected to the implant. The delivery catheter may have a handle that can manipulate the delivery catheter and the implant. Typically, the delivery of the implant may be performed under fluoroscopic and/or echo guidance. 
     The delivery system may use a sheath to cover the implant for delivery and a guidewire to advance and steer the delivery catheter into position with the implant at the distal end. The implant may be exposed by pulling the sheath back. Once exposed and delivered, the anchors of the implant may be embedded into the tissue surrounding and/or including the mitral valve. In some embodiments, the anchors of the implant may be retractable and/or helical-shaped. In some cases, the anchors may engage the tissue by pushing, pulling, and/or rotating the anchors. 
     The implant size and/or shape may then be changed by a number of adjustment mechanisms, including mechanisms that use nuts, clips, and/or cables. Some mechanisms serve as restraints to adjustably change the distance between two or more anchors on the implant, such as through a working range, and ultimately affect the size and/or shape of a valve annulus, such as the mitral valve annulus. The adjustment of these mechanisms may be performed by using rotational drivers and/or actuators at the proximal end of the handle of the delivery catheter. The rotational drivers and/or actuators may be used to compress or expand the implant at the operator&#39;s discretion to adjust the final size and/or shape of the implant (and hence, the mitral valve) as desired. The delivery system may be disconnected and removed once the implant has been delivered and adjusted as desired, and/or once mitral regurgitation has been reduced or eliminated. The implant may be left as a permanent implant. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The disclosed aspects will hereinafter be described in conjunction with the appended drawings, provided to illustrate and not to limit the disclosed aspects, wherein like designations denote like elements. 
         FIG. 1A  illustrates an example heart showing the left ventricle and the left atrium along with associated anatomical landmarks. 
         FIG. 1B  illustrates a top-down view of the mitral valve of the example heart illustrated in  FIG. 1A . 
         FIGS. 2A-2E  illustrate example ways for introducing a delivery catheter to the mitral valve. 
         FIG. 3  illustrates a transapical entry through the left ventricle and mitral valve using a delivery catheter having a guidewire. 
         FIG. 4  illustrates an example exposed and/or unsheathed implant at the end of the delivery catheter of  FIG. 3 . 
         FIG. 5A  illustrates the example implant of  FIG. 4  in an expanded state. 
         FIG. 5B  illustrates the example implant of  FIG. 5A  embedded in the tissue surrounding and/or including the mitral valve. 
         FIGS. 6A-L  illustrate example structural details of various embodiments of the implant illustrated  FIG. 5A-B . 
         FIG. 7  illustrates an example tilt adjuster that may be used with the delivery catheter illustrated in  FIG. 5A . 
         FIG. 8  illustrates an example tapered implant with a diamond pattern. 
         FIG. 9  illustrates an example retractable anchor mechanism that may be used in some implants. 
         FIG. 10  illustrates an example anchor being removed from an anchor cover or sheath. 
         FIG. 11  illustrates the expanded shape of an example implant from a top and side view. 
         FIG. 12  illustrates an example implant where the amplitude is nonsymmetrical about the implant&#39;s diameter. 
         FIG. 13  illustrates an example hook-and-wire rotational driver that can be used to manipulate an implant. 
         FIG. 14  illustrates an example two-arm rotational driver that is similar to the rotational driver of  FIG. 13 . 
         FIG. 15  illustrates an example hex rotational driver that can be used to manipulate an implant. 
         FIGS. 16A-B  illustrate a side-view and top-view of a rotational driver that can be used to rotate a nut over a strut in an appropriate direction. 
         FIGS. 17A-B  illustrate an example push-slider mechanism that may be used to manipulate an implant. 
         FIG. 18A  illustrates an example delivery system for an implant having forward (distal) facing anchors for entry from the left atrium, or for entry from a femoral vein and a transseptal puncture. 
         FIG. 18B  illustrates an example delivery system for an implant having proximal facing anchors for entry from a left ventricle (e.g., a transapical entry). 
         FIG. 19  illustrates a close-up of an example implant with proximal facing anchors with screw-and-clip mechanisms to adjust the shape and/or size of the implant. 
         FIG. 20  illustrates a close-up of the implant of  FIG. 19  where the screw- and clip mechanisms reduce the diameter of the implant. 
         FIG. 21  illustrates a close-up of an example implant with distal facing anchors and screw-and-clip mechanisms to adjust the shape and/or size of the implant. 
         FIG. 22A  illustrates a close-up of an example implant with proximal facing anchors and connection arms connected to the implant. 
         FIG. 22B  illustrates an example implant with proximal facing anchors and connection arms attaching the implant to a delivery system. 
         FIG. 23  illustrates example anchor configurations of various shapes. 
         FIG. 24  illustrates an example implant with anchors covered with slideable elements. 
         FIG. 25  illustrates the example implant from  FIG. 24  with anchors exposed and ready for implantation. 
         FIGS. 26A-C  illustrate an example anchor that has a helical shape that can be rotated through an extension of an implant strut to engage the tissue surrounding and/or including a mitral valve. 
         FIG. 27  illustrates an example anchor that has a helical shape that can be rotated through an implant strut to engage the tissue surrounding and/or including a mitral valve. 
         FIG. 28  illustrates an example implant with anchors that have a helical shape. 
         FIG. 29  illustrates the example implant of  FIG. 28  in an expanded state. 
         FIG. 30  illustrates the example implant of  FIG. 29  where the anchors have been extended. 
         FIG. 31  illustrates the example implant of  FIG. 30  where the example implant has been contracted. 
         FIG. 32  illustrates an example replacement prosthetic heart valve operably coupled to an example implant. 
     
    
    
     DETAILED DESCRIPTION 
     This disclosure encompasses all changes, substitutions, variations, alterations, and modifications to the example embodiments herein that a person having ordinary skill in the art would comprehend. Similarly, where appropriate, the appended claims encompass all changes, substitutions, variations, alterations, and modifications to the example embodiments herein that a person having ordinary skill in the art would comprehend. Moreover, reference in the appended claims to an apparatus or system or a component of an apparatus or system being adapted to, arranged to, capable of, configured to, enabled to, operable to, or operative to perform a particular function encompasses that apparatus, system, component, whether or not it or that particular function is activated, turned on, or unlocked, as long as that apparatus, system, or component is so adapted, arranged, capable, configured, enabled, operable, or operative. For example, various embodiments may perform all, some, or none of the steps described above. Various embodiments may also perform the functions described in various orders. 
     Although the present invention has been described herein in connection with several embodiments; changes, substitutions, variations, alterations, transformations, and modifications may be suggested to one skilled in the art, and it is intended that the present invention encompass such changes, substitutions, variations, alterations, transformations, and modifications as falling within the spirit and scope of the appended claims. 
       FIG. 1A  illustrates an example heart showing the left ventricle and the left atrium along with associated anatomical landmarks. Left atrium  102  receives oxygenated blood from the pulmonary veins (e.g., pulmonary vein  106 ). When left atrium  102  contracts, mitral valve  104  opens and blood leaves left atrium  102  through mitral valve  104  into left ventricle  105 . When left ventricle  105  contracts, mitral valve  104  closes and aortic valve  103  opens. Blood then flows into aorta  101 , which carries blood away from heart  100  to the rest of the body. 
       FIG. 1B  illustrates a top-down view of the mitral valve of the example heart illustrated in  FIG. 1A . Mitral valve  104  has two leaflets, anterior leaflet  120  and posterior leaflet  124 . Anterior leaflet  120  is located proximal to aorta  121 , and comprises of segments A 1 , A 2 , and A 3 . Posterior leaflet  124  is located distal to aorta  121 , and comprises of scallops P 1 , P 2 , and P 3 . Scallops P 1 , P 2 , and P 3  are extensions along the line of closure that allow the leaflets to accommodate the curved shape of the valve. Anterior leaflet  120  and posterior leaflet  124  come together at anterolateral commissure  123  and posteromedial commissure  122 . 
     Mitral valve incompetence may occur when mitral valve  104  does not close properly when heart  100  pumps out blood. This can lead to blood regurgitating left ventricle  105  ( FIG. 1A ) back into left atrium  102  when left ventricle  105  contracts. The regurgitation may lead to symptoms including dyspnea, fatigue, orthopnea, and/or pulmonary edema. 
       FIGS. 2A-2E  illustrate example ways for introducing a delivery catheter to the mitral valve.  FIG. 2A  illustrates various common points of entry for a delivery catheter to access heart  100  of person  250 . Delivery catheters may be used for delivering materials to a location of the body, including drugs, therapeutic treatments (e.g., energy for ablation), diagnostics, and/or implants. Typically, a delivery catheter has a long, flexible tubular portion that may be inserted into the lumens of arteries or veins. A person having ordinary skill in the art should appreciate that there are any number of entry points and/or ways that a delivery catheter may be inserted into the body. A few examples are described herein for illustration. A delivery catheter may be inserted into heart  100  percutaneously or through a cut-down procedure through the right or left femoral artery from point  252  or  256  in the legs and/or groin. A delivery catheter may also be inserted into heart  100  through the brachial arteries from points  254  and  253  in the arms. Another common entry point for a delivery catheter may be point  255  in the neck, which allows the catheter to be inserted into the jugular vein. 
     Once inserted into the body,  FIG. 2B  further illustrates common entry points for introducing a delivery catheter to mitral valve  104  of heart  100 . Included are transseptal entry  202 , transatrial entry  201 , and transapical entry  203 , which will be discussed in more detail. 
       FIG. 2C  illustrates an example transseptal entry. Delivery catheter  211  may be introduced to right ventricle  215  through a venous entry in the leg and/or groin. Delivery catheter  211  may then pass to left atrium  102  through transseptal puncture  212  in order to reach mitral valve  104 . 
       FIG. 2D  illustrates an example transatrial entry. Delivery catheter  220  is introduced to heart  100  through puncture  221  in the wall of left atrium  102  to mitral valve  104 . From left atrium  102 , delivery catheter  220  may reach mitral valve  104 . 
       FIG. 2E  illustrates an example transapical entry. Delivery catheter  231  is introduced through the apex of the heart through puncture  232  into left ventricle  105 . From there, delivery catheter  231  may reach mitral valve  104  and left atrium  102 . 
     There may be additional paths for reaching mitral valve  104 . For example, a delivery catheter may reach mitral valve  104  through pulmonary vein  106 . A delivery catheter may also use a transaortic entry. Embodiments of the present invention are not limited to any particular way of gaining access to the mitral valve. A person having ordinary skill in the art should appreciate that the methods and systems of this disclosure are not limited to any particular path(s) and may be readily adaptable to others not specifically described. However, the aforementioned entry points are a few illustrative examples of how embodiments of this disclosure may be introduced to mitral valve  104 . 
       FIG. 3  illustrates a transapical entry through the left ventricle and mitral valve using a delivery catheter having a guidewire. Guidewire  306  may guide delivery catheter  301  into left ventricle  105  through puncture  232  at the apex of heart  100 . From left ventricle  105 , guidewire  306  may further guide delivery catheter  301  into left atrium  102  through mitral valve  104 . 
     The implant (not pictured) may be carried in a compressed state at the distal end of delivery catheter  301  and housed in sheath  308 , which can be an outer tubular jacket, during initial navigation. Such compression may be desirable in order to advance the implant in situ for positioning in the body via arterial or venous entry without having the implant interact with arterial or venous tissue, and/or any other tissue of the body before being delivered to left atrium  102 . 
     The size of delivery catheter  301  may be, for example, generally within the range of about 10 to about 35 French in diameter, but may typically be about 24 French. Delivery catheter  301  may have a catheter length of about 45 to 100 centimeters in some embodiments. The proximal end of delivery catheter  301  may include a handle for operator interface and control. The handle may allow the implant, guidewire  306 , and/or delivery catheter  301  to be manipulated within the body by curving tip  307  and angling the delivery catheter for accurate positioning. Alternatively, through axial, distal, and/or proximal advancement of one or more control wires or cables, tip  307  of delivery catheter  301  can be tensioned and/or deflected to alter the shape of the distal end of delivery catheter  301 . Tip  307  may also be rotationally repositioned to match the anatomical needs for the target valve area or position. Guidewire  306  may pass through delivery catheter  301  and extend through tip  307 . Guidewire  306  may aid in the navigation of delivery catheter  301 . Guidewire  306  may measure, in some cases, from about 0.014 inches to 0.035 inches in diameter, but in some cases, the larger 0.035 inch in diameter may be preferable. 
       FIG. 4  illustrates an example exposed and/or unsheathed implant  400  at the end of the delivery catheter of  FIG. 3 . Implant  400  may be exposed and/or unsheathed by pulling back sheath  308  covering it, or alternatively pushing the implant distally past the sheath  308  in other embodiments. The covered state was illustrated in  FIG. 3 . Connection arms  401  run through delivery catheter  301  to implant  400  and allow for translation of forces for adjusting implant  400  and/or moving it around for positioning. These movements may include translational, rotational, and/or angular adjustments from the handle of delivery catheter  301 . Connection arms  401  and delivery catheter  301  can be separated from implant  400 , leaving the implant engaged in the heart after delivery and implantation. 
     Any implant of this disclosure (e.g., implant  400 ) may be constructed from, for example, metallic materials and/or polymers with sufficient structural integrity to reshape a mitral valve. The material may also be chosen based on biocompatility and fatigue resistance. Implant material(s) could include stainless steel, Nickel-Titanium, Cobalt-Chromium, Pyrolytic Carbon, Nitinol, polymer materials (e.g., PEEK), and/or other suitable implant materials. In some cases, the implant may also be coated with drug-eluting material to prevent fibrosis and/or clotting. 
     The implant may be laser cut from a tubular member to form the basic shape. The implant may also be heat-set into a shape for further assembly, which may include the further steps of electrochemical etching and/or a secondary polishing to remove irregular and/or unwanted material. These further steps may be used to smoothen the surface of the implant. Alternatively, the implant could be formed from a wire that is fused together by a laser. The implant may generally comprise of a plurality of, for example sinusoidal strut elements joined at proximal and distal apexes to create a zigzag pattern. In some embodiments, the implant may comprise a frame comprising a plurality of struts connected to a plurality of anchors near the ends of the struts. The frame of the implant may include a central lumen therethrough. The struts may also form a diamond-shaped pattern similar to an expanded Palmaz coronary stent, or the strut arms could have a flat plateaued segment therebetween at the apex in some cases. In other words, the apices should have a sharp edge, a curved edge, or a flat top among other geometries. The implant could be configured to multiple shapes and sizes during processing, including its initial laser-cut, tubular shape and size, and a heat-set shape and size for further processing (e.g., polishing and assembling). The implant may have a central lumen therethrough. 
     In some embodiments, the initial tube from which the implant is cut may have an outside diameter that could vary from 4 to 10 millimeters in diameter, however, a diameter of about 8 millimeters could be used in most cases. The initial tube wall thickness may be about 0.008 to about 0.040 inches, but could typically be about 0.020 inches. The laser-cut implant with a sinusoidal shape may have an axial length of about 10 to 40 millimeters. In some cases, an axial length of about 20 millimeters may be used. The implant may have, for example, between 4 to 32 strut elements, however, typically 8 to 16 struts may be used. 
     The configuration of the laser-cut pattern could have a connected diamond pattern and/or a sinusoidal or other geometry with a plurality of integral or separately formed anchors comprising barbs and/or hooks to engage heart tissue for securement and/or permanent fixation. The anchors may extend distally from some and/or all of the struts and/or from the apexes of the struts. The anchors may be adapted to engage a dilated mitral annulus, and may be contractible either actively or passively with the implant, as will later be discussed. The anchors could also be internally or externally mounted to the implant allowing them to be covered or retracted during delivery and/or positioning. For tissue engagement, the anchors may utilize a single barbed element or a plurality of barbed elements. 
     Additionally, the barbed elements of each anchor could be of similar lengths and orientations, or various lengths and orientations depending upon the implant area tissue and surrounding sensitivity to tissue engagement. Additionally, the barbs could match the tubular shape of the as-cube tube, or be formed secondarily in and/or out of the tubular surface plane, which may angle the barb portion out of the cylindrical shape. 
     The implant could comprise one or more sinusoidal struts having eight curved apexes with eight anchors to engage the tissue at the distal end of the implant, where the anchors measure about 3 to 4 millimeters in length with 1, 2, 3, 4, or more barbs per anchor in some cases. The anchors may be further processed by twisting and/or rotating the anchors, their hooks, and/or their barbs after laser cutting. Such twisting and rotating may create more complex shapes (e.g., helical, tortious, and/or amorphous shapes) for improved tissue attachment in some cases. 
     The implant may be delivered in a first diameter and/or configuration, wherein the first diameter allows the implant to be carried within the sheath of the delivery catheter. In some cases, the implant may expand to a second diameter and/or configuration (e.g., by the retraction of the sheath and/or other mechanisms described in this disclosure), which would allow the implant to be expanded for positioning. Once desirably positioned, the implant could be attached by intimate tissue contact and/or force either longitudinally or radially outward. In some cases, such attachment would be performed by engaging the anchors of the implant to tissue surrounding and/or including the mitral valve. The implant may change size and/or shape to a third diameter and/or configuration after tissue engagement in order to change the shape of the mitral valve. The third diameter may be a reduced diameter in comparison to the second diameter, and could ease mitral regurgitation by pulling the tissue surrounding and/or including the mitral valve closer together, thereby reducing the mitral valve. Adjustments could be made to the implant by mechanisms coupled to the delivery catheter&#39;s handle located exterior to the patient. 
     Changes to the third diameter may be used to alter the geometry of the mitral valve area and its surrounding tissue. The natural opening of the mitral valve may not be a perfectly circular shape, but may be shaped more like a saddle with amplitude and ovality. Therefore, the final third diameter may not be perfectly circular, but may be more elliptical and/or amorphous with some customization required depending upon the patient&#39;s anatomy and the nature of the valvular incompetency. This customization can be achieved through selectively modifying the implant shape to better reduce the regurgitant flow through the patient&#39;s mitral valve. Echo imaging and/or fluoroscopy may indicate the desirable valve cooptation. The customization may include selectively and independently altering the sinusoidal element angles of the implant. For example, if the arms of one or more struts of the implant were moved closer to one another, the anchors connected to the arms of the one or more struts would also be moved closer to one another, which would move the mitral tissue attached to each anchor closer together. Numerous example mechanisms for such movements will be described in this disclosure. 
     As an example, the implant may be constructed from a Nitinol tubing measuring about 8 millimeters in diameter and laser-cut into a pattern allowing for expansion and heat-setting. The implant height could be about 10 to 30 millimeters and could vary around the perimeter to match the saddle shape of the mitral valve. The laser cut patterns include a sinusoidal or diamond shape allowing for the implant to be reduced to the first diameter of about 5-8 millimeters for loading into a delivery catheter. The implant may be expanded to a second diameter of about 25 to 50 millimeters for implantation into the tissue surrounding and/or including a mitral valve. The third diameter may be from about 20 to 25 millimeters to set the diameter of the mitral valve. The implant could be heat set into a round and/or cylindrical shape with tapering at the top and/or bottom to match the anatomical location. Accurate imaging by means of fluoroscopy and/or ultrasound imaging or other conventional imaging tools to view surrounding tissue and the implant delivery placement is typical and could be used for implantation and/or adjustment. 
     As will be described, for delivery, the implant may be connected to a delivery catheter by a plurality of receiver holes formed as part of the struts of the implant. The receiver holes may be designed to mate with a plurality of connection arms (e.g., connection arms  401 ) connected to the delivery catheter. The receiver holes can be an integral part of the implant structure or a secondary structure coupled to the implant that may or may not be implanted. The connection arms may have radial flexibility allowing the implant to expand to various diameters. The connection arms may join the implant to the delivery catheter and tilt the implant by lengthening and shortening the connection arms on opposing sides via handle adjustment. Such tilting may be induced for anatomical positioning and/or angular adjustments. The ability to tilt the implant before engaging the anatomy compensates for patient anatomical variability. In some embodiments, tilting can vary from minus 30 degrees to plus 30 degrees at any selected angle. Alternatively, the delivery catheter may be pre-shaped with a fixed angle to accommodate anatomical irregularities and/or variations from patient-to-patient. This angular adjustment could also occur through delivery catheter angle adjustments at the distal end through cable tensioning or bending of the distal end of the catheter to influence the angle. 
       FIG. 5A  illustrates the example implant of  FIG. 4  in an expanded state. This expansion could be activated with a force generated from the handle of delivery catheter  301  through the use of connection arms  401  and/or expandable members such as balloons (e.g., a balloon disposed within implant  400  and/or disposed within connection arms  401 ) to expand implant  400  to a desired diameter. The expansion could be uniform and/or circular, an elliptical shape, and/or amorphously shaped to match the anatomy of mitral valve  104 . The expansion could also be tailored to match the patient&#39;s specific anatomical needs if an irregular shape were desirable. Once the implant is expanded, the protruding anchors of implant  400  may be embedded in the tissue surrounding and/or including the mitral valve by pulling or pushing implant  400 , and/or any other mechanism described in this disclosure. 
       FIG. 5B  illustrates the example implant of  FIG. 5A  embedded in the tissue surrounding and/or including the mitral valve. Accordingly, implant  400  may be positioned so that it and mitral valve  104  may be reduced in diameter and/or dimension as desired. In some cases, the reduction of implant  400 , and consequently mitral valve  104 , could be achieved by passive forces through the hysteresis of the material of implant  400 . For example, implant  400  may comprise of material(s) (e.g., Nitinol and/or any other material mentioned in this disclosure) that has an equilibrium size and/or shape that is smaller than the expanded state in which it is embedded into the tissue surrounding and/or including the mitral valve. As implant  400  returns to its equilibrium size and/or shape, a radially inward restoring force reduces both implant  400  and mitral valve  104 , which in turn can reduce mitral regurgitation. In some embodiments, the mitral valve size and/or shape change can occur at the level of the proximal or distal end of the implant. In contrast to conventional annuloplasty rings which are implanted on an external cardiac surface, some embodiments as disclosed herein can operably attach to tissue on an internal (e.g., luminal surface) in the vicinity of the valve annulus. 
     As another example, the material of implant  400  may also be configured to react at body temperature to change its size and/or shape. The thermal expansion and retraction of the material may be used to apply the aforementioned passive forces. When the material (e.g., Nitinol or any other material mentioned in this disclosure) is heated, it expands, and when it is cooled, it retracts. In some embodiments, implant  400 , or portions of implant  400 , may be cooler than body temperature when implanted, and expand to a larger shape when it is warmed by body heat. At body temperature, implant  400  may then be the desired size and/or shape to attach to the tissue surrounding and/or including the mitral valve. Implant  400  may then be reduced and/or adjusted as desired by systems and methods described in this disclosure. 
     In the alternative, implant  400 , or portions of implant  400 , may be at a temperature warmer than body temperature when it is attached to the tissue surrounding and/or including the mitral valve. As implant  400 , or portions of implant  400 , cools to body temperature, the restoring forces may create an inward radial force that reduces both the size of implant  400  and mitral valve  104 , which in turn can reduce mitral regurgitation. 
     In some cases, implant  400  is kept at a desired temperature (e.g., warmer or cooler than body temperature) before it is attached to delivery catheter  301 . In this way, it may be warmer or cooler as it is delivered. 
     In some embodiments, delivery catheter  301  ( FIG. 3 ) may also provide a microenvironment that helps hold the temperature of implant  400  before it is delivered to left atrium  102 . In this way, it may allow implant  400  to be delivered at a temperature warmer or cooler than body temperature. For example, delivery catheter  301  may contain a heating coil, cooling elements, chemical heating/cooling, insulation, and/or any thermal control known in the art. In some embodiments, the implant can comprise magnetically controlled shape memory material (MSMs), including Fe—C, Fe—Pd, Fe—Mn—Si, Co—Mn, Fe—Co—Ni—Ti, Ni2MnGa, Co—Ni—Al, Ni—Mn—Ga, and the like. MSMs exhibit a paramagnetic/ferromagnetic transition besides a thermoelastic martensitic transformation. In some embodiments, the implant may be comprised of shape memory polymers (SMPs). Such SMPs may hold one shape in memory or may hold more than one shape in memory. SMPs which hold one shape in memory are generally characterized as phase segregated linear block co-polymers having a hard segment and a soft segment. The hard segment is typically crystalline, with a defined melting point, and the soft segment is typically amorphous, with a defined glass transition temperature. Sometimes, however, the hard segment is amorphous and the soft segment is crystalline. In any case, the melting point or glass transition temperature of the soft segment is substantially less than the melting point or glass transition temperature of the hard segment. Changes in temperature cause the SMP to revert between the original shape and the memory shape. Examples of polymers used to prepare hard and soft segments of SMPs include various polyethers, polyacrylates, polyamides, polysiloxanes, polyurethanes, polyether amides, polyurethane/ureas, polyether esters, and urethane/butadiene copolymers. 
       FIGS. 6A-L  illustrate example structural details of various embodiments of the implant illustrated in  FIGS. 5A-B . One or more of the structural details and variations illustrated may be used in different embodiments of the implant, and/or used in combination in a single embodiment. A person having ordinary skill in the art should also appreciate that any number of the adjustable restraints described may be used on implant embodiments to adjust the size and/or shape. The assortment of sizes and/or shapes presents a range (e.g., a working range) of configurations of the implant embodiments. 
       FIG. 6A  is a close-up view of a portion of an implant having a nut-and-thread mechanism for size and/or shape adjustment. In this embodiment, implant  600  comprises struts, such as strut  608 . Strut  608  itself comprises of threaded crown  601  at its apex, and arms  606  and  607 . Adjacently connected to arms  607  and  606  are anchors  604  and  605 , respectively, such as at the base (e.g., the distal end) of the implant. Threaded crown  601  is encircled by nut  602 , which can be used for customization of the size and/or shape of implant  600 . For example, the positioning of nut  602  along threaded crown  601  may be used to adjust the relative positioning of anchors  604  and  605 . When nut  602  is positioned closer to anchors  604  and  605  along strut  608 , arms  606  and  607  may come closer together, which leads to anchors  604  and  605  coming closer together. Nut  602  may be positioned any number of ways, including by rotation, sliding, pushing, pulling, and/or any means of mechanically driving the nut. Other nuts like nut  602  may encircle the other threaded crowns of struts of implant  600 . In this way, these nuts may independently position other anchors. In some cases, such positioning occurs after the anchors are embedded in the tissue surrounding and/or including a mitral valve. Through the manipulation of these nuts and struts, and consequently the anchors connected to those struts, implant  600  may be manipulated and/or adjusted as desired to shape mitral valve  104  as desired. It should be appreciated by one of ordinary skill in the art that the independent adjustments of these nuts permit implant  600  to be sized and/or shaped in many different ways. Such ability to shape implant  600  may be clinically desirable in patients with mitral regurgitation needing nonsymmetrical annular adjustment. It will not, however, prohibit symmetrical adjustment if desired. Rather, independent adjustments allow a physician or operator to adjust implant  600  to best suit the patient&#39;s regurgitant flow reduction. In some embodiments, the threads and/or nuts can be configured to extend a length axially along one, two, or more of the struts, such as at least about, about, or no more than about 10%, 20%, 30%, 40%, 50%, 60%, 70%, 80%, or 90% of the amplitude of the struts (e.g., the length of the device along its longitudinal axis). 
     Nut  602 , or other nuts, may be circular, non-circular, an oval, amorphous, and/or any shape and/or size to conform to the shape of the struts. It may be constructed from material(s) including stainless steel, Nickel-Titanium, Cobalt-Chromium, Pyrolytic Carbon, Nitinol, polymer materials (e.g., PEEK), and/or other suitable implant materials. 
     Implant  600  may also have a plurality of receiver holes (e.g., aperatures), such as receiver hole  603 , which may also be used to manipulate implant  600 . Receiver holes may be in any number of orientations, including vertically positioned as in  FIG. 6A , horizontal, angled, etc. with respect to the long axis of the implant. They may be located anywhere along the struts, anchors, and/or implant as desired, aligned horizontally in a ring formation, staggered and axially offset, and the like. 
       FIG. 6B  is an above (top)-view of  FIG. 6A  and illustrates an example way of adjusting the shape of an embodiment of implant  600  through the rotation nut  602 . Nut  602  is positioned on threaded crown  601  of strut  608 . The threads may be configured such that the rotation of nut  602  repositions nut  602  on threaded crown  601 , thus adjusting the position of arms  606  and  607 , and consequently anchors  604  and  605  ( FIG. 6A ). For example, the threads of threaded crown  601  may be angled and/or otherwise configured to resemble the threads of a screw. The rotation of nut  602  could be driven through by the external handle of the delivery catheter and transmitted through a shaft, rod, and/or tube that connects to nut  602 . Again, other nuts may be used to move other anchors, such as anchor  610 . 
       FIG. 6C  illustrates a close-up of an example mechanism for connecting and/or separating connection arms from implants. In this embodiment, an implant (e.g., implant  400 ) has horizontal receiver holes (e.g., receiver holes  626  and  625 ) on the interior of the implant. A plurality of connection arms may be connected to the receiver holes of the implant during delivery. These connection arms may reversibly or detachably connect the implant to the delivery catheter, and may be used to initially expand the implant to the second diameter previously described. 
     It may be desirable to disconnect the connection arms from the implant at some time. For example, such a disconnection may be desirable after the implant has been positioned and the anchors of the implant have been embedded in the tissue surrounding and/or including a mitral valve, and the implant has been adjusted. Disconnection at this time would allow the connection arms and delivery catheter to be removed from the body, leaving only the implant. The separation of the connection arms from the implant may be performed independently for each receiver hole, or performed on all receiver holes of the implant simultaneously. 
     The connection arms may comprise a plurality of tubular members with wires. The tubular members and wires may interact with the receiver holes of the implant while the implant is connected to the connection arms. For example, tubular member  624  is positioned around receiver hole  626  such that wire  627  passes through tubular member  624  and receiver hole  626 . Wire  627  may be held in place by a clip, hook, snag, loop, knot, magnet, adhesive, and/or any other mechanism(s) known in the art for holding a wire in place. In such a position, connection arm  628  is connected to the implant. Wire  627  can also be cut, electrolytically detached, or otherwise detached. 
     Connection arm  629  is disconnected. Tubular member  622  has been removed so that wire  620  no longer passes through receiver hole  625 . Accordingly, tubular hole  623  of tubular member  624  is no longer held in position around receiver hole  625 . 
       FIG. 6D  illustrates an implant embodiment that may be adjusted in size and/or shape using a screw-and-clip mechanism. Clip  634  is placed over a strut having arms  636  and  637 . The positioning of clip  634  along arms  636  and  637  may be adjusted by screw  630 , which passes through boss  635  (e.g., a screw retainer) and clip  634 . Clip  634  is threaded such that the rotation of screw  630  moves clip  634  up and down. For example, clip  634  may have threads that run in the opposite direction as the threads of screw  630 . 
     As clip  634  moves down arms  636  and  637 , arms  636  and  637  move closer together, which causes anchors  632  and  633  to gather closer to one another. In this way, clip  634  may be used to adjust the size and/or shape of an implant. A person having ordinary skill in the art should recognize that an implant may have a plurality of screw-and-clip mechanisms, such as the one just described, connected to a plurality of struts. By positioning the clips, independently or simultaneously, the size and/or shape of the implant may be adjusted as desired. 
     The screw-and-clip mechanism may be attached to the outer diameter or the inner diameter of the implant, and could use a single or a plurality of screws and clips, depending upon the implant crown quantity and/or as desired. The threaded members of the screws and clips may measure from, in some embodiments, about 0.4 millimeters in diameter to about 1.5 millimeters and be constructed from stainless steel, Nickel-Titanium, Cobalt-Chromium, Pyrolytic Carbon, Nitinol, polymer materials (e.g., PEEK), and/or other suitable implant materials. In some cases, a #2-56 thread size may be used. 
       FIG. 6E  illustrates a cable mechanism that may be used to adjust the size and/or shape of an implant embodiment. In some embodiments, cable  638  encircles implant  642 , e.g., in a direction transverse or oblique to the longitudinal axis of the implant and applies a radially restrictive force on implant  642 , which may be used to control the size and/or shape of implant  642 . Cable  638  may pass through a plurality of the receiver holes of implant  642  (e.g., receiver hole  603 ). Cable  638  may be a thread, suture, cable, string, wire, ribbon, and/or any sort of structure that could pass through the receiver holes (e.g., receiver hole  603 ) of implant  642 . Cable  638  may be tied off at knot  639 . In some cases, knot  639  may be a moveable knot (e.g., a slip knot) that allows the length of cable  638  to be adjusted. For example, force may be applied to knot  639  to pull or push it (e.g., medially or laterally) such that cable  638  shortens or lengthens. Force may also be applied to one or more points of cable  638 , including the ends of cable  638 , in order to pull portions of cable  638 , thereby shortening or lengthening cable  638 . The force may be applied through mechanical drivers and/or actuators, wherein the force is applied through the delivery catheter from the handle of the delivery catheter. 
     In some embodiments, cable  638  may also be shortened by wrapping portions of the cable around a spool/ream. For example, portions of cable  638  may initially wrap around the spool/ream during delivery, and the spool/ream may be rotated in order to cause more/less of cable  638  to wrap around it. The rotation may be performed by a rotational driver (e.g., the rotational drivers illustrated in  FIGS. 13-15 ). In this way, cable  638  may be shortened or lengthened. 
     Again, receiver holes or apertures (e.g., receiver hole  603 ) may be positioned in various places on implant  642 , angles, and/or configurations. The receiver holes may also be placed uniformly or non-uniformly across implant  642 . For example, receiver holes may be adjacent to every anchor of implant  642  or adjacent to fewer than every anchor of implant  642  in order to achieve the desired shape and/or size of implant  642 . 
       FIG. 6F  illustrates a top-view and a side-view of an implant embodiment. In this embodiment, implant  643  has horizontal receiver holes on its interior. As illustrated, cable  640  passes through all the receiver holes of implant  643 . However, cable  640  may also pass through a number of receiver holes less than all of the receiver holes of implant  643 . The shape and/or size of implant  643  may be adjusted by loosening or tightening cable  640  using any system and/or method of loosening and/or tightening cables described in this disclosure. Typically, cable  640  remains with implant  643  after implant  643  has been implanted in order to maintain the shape and/or size of implant  643 . However, cable  640  may also be removed and/or disconnected from implant  643  as desirable. 
       FIG. 6G  shows a side-view and a top-view of an implant embodiment using a cable mechanism with a cross-cable oriented in a direction other than around an outer diameter or an inner diameter of an implant, such as traversing the outer diameter or inner diameter of an implant. In this embodiment, cable  650  passes through some, but not all, of the receiver holes of implant  653 . Additionally, cross-cable  651  is used to connect segments of cable  650 , and may or may not pass through a receiver hole. Cross-cable  651  may be connected to cable  650  by knots, such as knot  652 , which may be moveable knots (e.g., a slip knot) that allow the length of cross-cable  651  to be adjusted. For example, force may be applied to knot  652  to pull or push it (e.g., medially or laterally) such that cross-cable  651  shortens or lengthens. Force may also be applied to one or more points of cross-cable  651 , including the ends of cross-cable  651 , in order to pull cross-cable  651  laterally, thereby shortening or lengthening cross-cable  651 . The force may be applied through mechanical drivers and/or actuators, wherein the force is applied through the delivery catheter from the handle of the delivery catheter. Just like cable  640 , cross-cable  651  may also be adjusted by using a spool/ream connected to a rotational driver (e.g., the rotational drivers illustrated in  FIG. 13-15 ), wherein the rotation of the spool/ream causes more/less of cross-cable  651  to wrap around it. This may change the length of cross-cable  651 . 
     It should be appreciated by one having ordinary skill in the art that a cable may pass through different receiver holes in order to adjust implant  653  as desirable. Having a plurality of receiver holes allows variability in the shape and/or size of implant  653  using cables. Cross-cables, such as cross-cable  651 , may also allow further variability in shape and/or size of implant  653 . For example, having a cross-cable may allow a precise adjustment along a particular plane as the cross-cable is shortened and/or lengthened. Cross-cables may be placed anywhere along a cable as desired. 
     Even more variability in shape and/or size of an implant may be achieved by further variations in cable configurations. For example, a plurality of independent cables may be used to connect various receiver holes of an implant.  FIG. 6H  illustrates an implant embodiment having a plurality of independent cables. Cables  661 ,  662 , and  663  independently connect various receiver holes of implant  664 . They may be connected to the receiver holes by knots, such as knot  660 . The shape and/or size of implant  664  may be adjusted by loosening or tightening one or more of cables  661 ,  662 , and  663  using any system or method of loosening and/or tightening cables described in this disclosure. In other embodiments, independent cables may cross each other and/or be configured to connect any receiver hole with another. In some cases, a single receiver hole may be connected to more than one cable. In some embodiments, the cables do not completely follow the outer diameter or inner diameter of the implant. 
       FIG. 6I  illustrates an alternative that may use a similar screw-and-clip mechanism as  FIG. 6D . The screw-and-clip mechanism uses screw  670 , clip  671 , and boss  673 . The screw may vary in size depending on the size of the implant and/or as desired. In some embodiments, locking ring  672  may be positioned distally to clip  671 , where locking ring  672  locks the strut arms  676  and  677  in position, and consequently locks the position of anchors  674  and  675 . Locking ring  672  may remain on the implant after screw  670 , boss  673 , and/or clip  671  have been removed. 
     There are a number of ways locking ring  672  may be positioned. In some embodiments, locking ring  672  is initially within clip  671 . Locking ring  672  may be configured such that it stays in place along arms  676  and  677  once it has been advanced. For example, locking ring  672  may have directional fasteners, cogs, and/or tangs that only allow it to move downward (e.g., advance) arms  676  and  677 . As screw  670  is turned in one direction, locking ring  672  advances down arms  676  and  677 . Once locking ring  671  is positioned, screw  670  may be turned in the other direction to remove screw  670 , clip  671 , and/or boss  676 , and leave locking ring  671 . 
     In other embodiments, clip  671  and/or locking ring  672  may be positioned by a cable (e.g., thread, suture, cable, string, wire, etc.). For example, clip  671  and/or locking ring  672  may be connected to a cable. The cable may thread through a single or plurality of holes located on arm  676 , and then up through holes located on clip  671  and/or locking ring  672 . The cable could then connect back down through another hole located on arm  677 . When pulled, the cable may force clip  671  and/or locking ring  672  down arms  676  and  677 , which in turn positions anchors  674  and  675 . The cable could subsequently be removed, leaving clip  671  and/or locking ring  672  behind holding arms  674  and  675  in position. 
       FIG. 6J  illustrates an implant embodiment having diamond-shaped struts and sharp, pointed apices. In this embodiment, strut  682  has threaded arms  681  and  686  and anchor  684  at its bottom (base). Nut  680  may be used to position threaded arms  681  and  686  of strut  682 , and consequently position anchor  684 . For example, nut  680  may be rotatable about the threads of threaded arms  681  and  686 , which may be configured such that the rotation of nut  680  moves nut  680  axially up or down strut  682 . As nut  682  moves down strut  682 , it may tighten strut  682  and/or bring threaded arms  681  and  686  closer together. As a result, anchor  684  moves closer to neighboring anchors, such as anchor  685 . Implant  665  may have a plurality of struts and/or nuts. The nuts may be rotated independently or simultaneously in order to adjust the size of implant  665 . 
       FIG. 6K  illustrates a variation of  FIG. 6J . In this embodiment, implant  667  has a plurality of diamond-shaped struts, which may be adjusted by clips that are on the lower parts of the struts. The clips may attach to the threaded arms of neighboring diamond-shaped struts. For example, strut  697  has threaded arm  696 , and strut  692  has threaded arm  695 . Threaded arms  695  and  696  are connected to anchors  694  and  698 , respectively. When clip  691  is rotated, it may move up or down threaded arms  695  and  696 . When clip  691  moves down towards anchors  694  and  698  along threaded arms  695  and  696 , threaded arms  695  and  696  move closer together. Accordingly, anchors  694  and  698  move closer together. 
     It should be noted that implants may have uniform/symmetrical configurations or non-uniform/non-symmetrical configurations. For example, an implant may have sinusoidal struts all around. In other embodiments, an implant may have diamond-shaped struts all around. In still other embodiments, an implant may have both sinusoidal struts and diamond-shaped struts, such as in an alternating fashion. Each strut of an implant may use the same mechanism(s) (e.g., one or more of the mechanisms and/or adjustable restraints illustrated in  FIG. 6A-L ) to adjust anchor positions, or any strut may use different mechanism(s) than other struts. In some embodiments, struts could have different shape patterns, such as a flat or plateaued segment in between ascending and descending arms. 
       FIG. 6L  illustrates various cable lock systems for cables such as cable  638  ( FIG. 6E ), cable  640  ( FIG. 6F ), cable  650  and  651  ( FIG. 6G ), and/or cables  661 ,  662 , and  663  ( FIG. 6H ). The cable lock systems may be used to lock the cables to a certain length, change the length of the cables (e.g., loosen or tighten, and/or lengthen or shorten), and/or connect cables to each other or to an implant. For example, cable  695  may have a ball-and-cone clasping mechanism. By way of illustration, cable  695  might have end  688  that connects to clasp cone  696 . The balls of cable  695  may uni-directionally pass through cone  696  by applying sufficient force. For example, ball  697  of cable  695  may be pulled through the larger end of clasp cone  696  through the smaller end by applying sufficient force. The amount of force required may be changed by the selection of clasp cone  696 , which may offer more or less resistance to the passing of ball  697  as desired. As balls are pulled through clasp cone  696 , the length of cable  695  shortens. The shape of clasp cone  697  prevents balls from being pulled through the smaller end of clasp cone  696  back through the larger end, thereby preventing cable  695  from being lengthened after it has been shortened. When cable  695  is used with an implant, cable  695  may be used to restrict the implant and hold the implant to a shape and/or size. The ball elements need not necessarily be spherical as shown, and can take the form of beads, cubical, rectangular, pyramidal, or other elements having at least one dimension greater than that of the cable. 
     Alternatively, a structure similar to a cable-tie may be used, such as a one-way ratchet or zip tie for example. For example, cable  699  may have a plurality of ridges. Clasp  698  may be attached to end  689  of cable  699 . Clasp  698  may be configured to interact with the ridges of cable  699  such that cable  699  can pass through clasp  698  when cable  699  is pulled with sufficient force in a certain direction. This mechanism may utilize a directional clip inside clasp  698 , where the clip slides into the ridges of cable  699 . When ridges are pulled through clasp  698 , cable  699  shortens. Because clasp  698  prevents cable  699  from being pulled in the opposite direction, clasp  698  prevents cable  699  from being lengthened. As a result, cable  699  may be used to restrict an implant. 
       FIG. 7  illustrates an example tilt adjuster that may be used with the delivery catheter illustrated in  FIG. 5A . Delivery catheter  301  may have tilt adjuster  702 . Tilt adjuster  702  may connect to connector arms  401 , which run through at least part of the length of delivery catheter  301  and connect to implant  400 . The sheath of delivery catheter  301  has been withdrawn to expose connector arms  401  and implant  400 . By actuating tilt adjuster  702 , connector arms  401  may be moved in order to tilt implant  400  as desired. In some cases, the movement of tilt adjuster  702  pulls and pushes the various wires in connector arms  401 , which in turn causes implant  400  to tilt and/or move out of plane. Such tilting may be desirable to navigate implant  400  into position in the heart. Typically, tilting can vary from minus 30 degrees to plus 30 degrees at any selected angle. Guidewire  306  may run through delivery catheter  301 . In some cases, guidewire  306  may extend through tip  307 , as also illustrated in  FIG. 5A . 
       FIG. 8  illustrates an example tapered implant with a diamond pattern. Implant  800  has a plurality of diamond cuts, such as diamond cut  801 . It also has a conical shape, where the top (distal to the anchors) is narrower than the bottom (proximal to the anchors). Implant  800  also has a plurality of receiver holes, such as receiver holes  802  and  803 , located at numerous spaced axially and/or radially apart places. Receiver holes may be located anywhere as desired on implant  800 . For example, a receiver hole may be located at a point on implant  800  in order to allow adjustment of sections of implant  800  adjacent to that point using cables and/or connection arms as previously described in this disclosure. By way of illustration, receiver hole  803  may be positioned near anchor  804  in order to allow a cable to connect to receiver hole  803  and adjust the position of anchor  804 . Receiver hole  803  may interact with cables in order to adjust the size and/or shape of implant  800  in any way(s) described in this disclosure. 
     In some embodiments, implant  800  may be initially configured such that the upper-end is smaller or larger in diameter than the lower-end, as pictured in  FIG. 8 , such as about or at least about 5%, 10%, 15%, 20%, 25%, 30%, 40%, 50%, or more greater than the other respective end. The lower-end may have anchors that are positioned to allow for an angular implantation of the anchors into the tissue surrounding and/or including the mitral valve. Once the anchors have been fixed to the tissue, the tapered implant could switch orientation so that the lower-end becomes smaller in size and the upper-end becomes larger. Such switching could be initiated by the downward force of embedding the anchors into the tissue, where the struts of the implant are configured to flip orientation due to the downward force. In some cases, the implant may have an equilibrium shape where the upper-end is larger than the lower-end. The downward force of embedding the implant while it is not in its equilibrium shape (e.g., while the lower-end is larger than the upper-end) may cause the implant to flip back to its equilibrium shape, thereby causing the lower-end to contract—which would cause the tissue connected to the lower-end to contract as well. 
     In other embodiments, the orientation switching may also occur due to radial forces, supplied from the handle of the delivery catheter, applied to the upper-end and/or lower-end of implant  800 . For example, connection arms connected to receiver holes of the upper-end of implant  800  may force the upper-end to expand. In some cases, a balloon may also be used to push the upper-end wider. In some cases, cables mechanisms, as in any cable mechanism described in this disclosure, may be used to pull the upper-end diameter larger and/or pull the lower-end diameter smaller. Tapered implants such as implant  800  may be diamond-patterned and/or sinusoidal. 
       FIG. 9  illustrates an example retractable anchor mechanism that may be used in some implants. Structure  900  may comprise retractable anchor  902 , which may be exposed and/or manipulated to interact with heart tissue. In some embodiments, anchor  902  may be lowered (e.g., moved distally) to be exposed, such as along a track or guide rail. In the exposed state, it may be embedded into tissue surrounding and/or including a mitral valve. In contrast, when anchor  902  is retracted (e.g., raised up, e.g., proximally), anchor  902  may not be exposed. The retracted state may be desirable to prevent interaction between anchors and tissue as the implant is positioned in the heart, and before the implant is embedded into the tissue surrounding and/or including a mitral valve. States between retracted and exposed may be used to control the depth anchor  902  embeds in tissue. Anchor  902  may be positioned using slide  904 , which may be coupled to spokes  906  of anchor  902 . Slide  904  may use lockable rails and/or clips that interact with spokes  906  to lock anchor  902  in place. 
       FIG. 10  illustrates an example anchor being removed from an anchor cover or sheath. For example, anchor  1002  may be covered by anchor cover  1001  to prevent interaction of anchor  1002  and tissue until anchor  1002  is exposed. Control rods, such as tubular member  1003 , which may be structured like tubular member  624  ( FIG. 6C ) and/or part of a connection arm, may be connected to anchor  1002  and pull it from anchor cover  1001 . In this way, anchor  1002  may be exposed in order to embed anchor  1002  into the tissue surrounding and/or including a mitral valve, and/or when desired. 
     In some embodiments, the actuation or exposure of anchor  1002  may be simultaneous with device expansion or secondarily initiated through the delivery catheter using a proximal control such as a push or pull member to advance anchor  1002  out of anchor cover  1001  using tubular member  1003 . An alternative may be a rotational or screw mechanism to advance anchor  1002  distally out of anchor cover  1001 . 
       FIG. 11  illustrates the expanded shape of an example implant from a top and side view. Implant  1100  may be an oval or substantially shape where the long axis measures about 30 to 40 millimeters and the short axis measures about 15 to 25 millimeters. Such a shape may be desirable in some circumstances in order to better match a desired mitral valve shape of a patient. In some embodiments, implant  1100  may be adjusted using mechanisms described in this disclosure in order to better match the desired shape of the mitral valve of a patient. 
       FIG. 12  illustrates an example implant where the amplitude is nonsymmetrical about the implant&#39;s diameter. Implant  1200  has a higher phase along the ends of its minor axis and a lower phase along the ends of its major axis. For example, anchor  1202  is positioned with an amplitude change  1201  higher than anchor  1203 . The clinical benefit of having such amplitude variation in the implant is that it allows the implant to be rotated into position where the lower phase, or longer struts, would reach out farther to the commissures of a mitral valve. This may be desirable in some cases because the mitral valve (and/or annulus) can be non-planar and more saddle-shaped, and also varies patient-to-patient and/or with the progression of a disease state. 
     In some embodiments, implant  1200  could feature a three-dimensional saddle shape similar to a GEOFORM ring from Edwards Lifesciences (Irvine, Calif.), which may better match the mitral valve&#39;s three-dimensional anatomy in some cases. This three-dimensional saddle shape may reflect a mitral valve&#39;s reduced anterior-posterior distance and an elevated P 2  segment. In some cases, the saddle shape has a top (distal to the anchors) linear segment, with a bottom (proximal to the anchors) bi-curved segment. In some embodiments, a plurality of anchors at opposing sides of the implant have a lower phase than the other anchors. 
     In some embodiments, the wall thickness of implant  1200  could measure about 0.010 to about 0.030 inches and could vary from top to bottom or on individual radial segments to change the stiffness of implant  1200  at locations about implant  1200 . Prior to implantation, diameter grinding and/or lateral grinding of implant  1200  could be used to selectively remove material around implant  1200  as needed. The grinders could be set with rotary fixtures to adjust implant  1200  accordingly for selective removal of material. 
     Adjusting the size and/or shape of an implant described in this disclosure may require mechanical drivers and/or actuators to adjust the position of adjustable restraints (e.g., screws, nuts, and/or cables) and/or other structures of the implant (see, e.g.,  FIGS. 6A-L ). Such mechanical drivers and/or actuators may include a variety of mechanisms that may rotate, slide, push, pull, and/or actuate structures of the implant. In some embodiments, rotational drivers may be connected to the implant through the handle of the delivery catheter. 
       FIG. 13  illustrates an example of a hook-and-wire rotational driver that can be used to manipulate an implant. Member  1300  may connect to a screw, nut, and/or other rotatable structure of an implant (see, e.g.,  FIGS. 6A-L ). Member  1300  may comprise tubular cover  1301  and loop  1304 . Rotational driver  1305  may comprise hook  1303  and stopper  1302 . Rotational driver  1305  may be connected to an external handle of the delivery catheter used to position the implant, where force is supplied to rotational driver  1305  at the handle. Rotational force may be applied through rotational driver  1305  to rotate member  1300 . 
     During delivery of the implant, rotational driver  1305  may be connected to member  1300 . In the connected position, hook  1303  is positioned in loop  1304 . Rotational driver  1305  and member  1300  may be pushed together such that hook  1303  and loop  1304  are positioned inside tubular cover  1301 . Stopper  1302  may be positioned in a ridge in tubular cover  1301  to further stabilize the connection between rotational driver  1305  and member  1300 , and to facilitate the transfer of rotational force from rotational driver  1305  to member  1300 . This transfer of rotational force may turn a nut (e.g., nut  602  of  FIG. 6A ), a screw (e.g., screw  630  of  FIG. 6D ), a spool/ream (e.g., to control the length of cable  640  of  FIG. 6F ), rotate the implant, and/or rotate any part/component of the implant. After the implant is positioned and/or sized/shaped as desired, rotational driver  1305  and member  1300  may be disengaged by pulling them apart and unhooking hook  1303  from loop  1304 . Rotational driver  1305  and member  1300  may also be re-engaged by placing hook  1303  in loop  1304 , and pushing rotational driver  1305  into tubular cover  1301 . 
       FIG. 14  illustrates an example two-arm rotational driver that is similar to the rotational driver of  FIG. 13 . Member  1400  may be fitted with hook  1406 . Rotational driver  1405  may be fitted with hook  1407  that is configured to connect with hook  1406 . 
     During delivery of the implant, rotational driver  1405  may be connected to member  1400 . In the connected position, hook  1407  is clasped to hook  1406 . Rotational driver  1405  and member  1400  may be pushed together such that hook  1407  and  1406  are positioned inside tubular cover  1401 . Stopper  1402  may be positioned in a ridge in tubular cover  1401  to further stabilize the connection between rotational driver  1405  and member  1400 , and facilitate the transfer of rotational force from rotational driver  1405  to member  1400 . This transfer of rotational force may turn a nut (e.g., nut  602  of  FIG. 6A ), a screw (e.g., screw  630  of  FIG. 6D ), a spool/ream (e.g., to control the length of cable  640  of  FIG. 6F ), rotate the implant, and/or rotate any part/component of the implant. After the implant is positioned and/or sized/shaped as desired, rotational driver  1405  and member  1400  may be disengaged by pulling them apart and unhooking hooks  1407  and  1406  from each other. Rotational driver  1405  and member  1400  may also be re-engaged by clasping hooks  1407  and  1406  together, and pushing rotational driver  1405  into tubular cover  1401 . 
       FIG. 15  illustrates an example hex rotational driver that can be used to manipulate an implant. Rotational driver  1510  has clasp  1513  and screwdriver head  1514 . During delivery, screwdriver head  1514  and screw head  1512  may be engaged with clasp  1513  closed around them. While engaged, rotational force may be transferred from rotational driver  1510  to screw  1511 . The rotational force may be supplied to screw  1511  by rotating screw driver head  1514  and/or rotating rotational driver  1510 . The rotation of screw driver head  1514  and/or rotational driver  1510  may be controlled and/or supplied from the external handle of the delivery catheter. 
     Screw  1511  may be, for example, any screw described in this disclosure (e.g., screw  630  of  FIG. 6D ). Screw  1511  may also be coupled to any rotatable part/component of an implant in order to transfer rotational force. For example, screw  1511  may be coupled to adjustable restrains, such as a nut (e.g., nut  602  of  FIG. 6A ), a spool/ream (e.g., to control the length of cable  640  of  FIG. 6F ), an implant (e.g., to rotate the implant), and/or rotate any part/component of the implant. 
     In some embodiments, rotational driver  1510  and screw  1511  may be disengaged by opening clasp  1513  and pulling rotational driver  1510  away from screw  1511 . The arms of clasp  1513  may be opened by a desired control such as a switch (e.g., a switch on the handle of the delivery catheter), pulley system, clasp system, and/or any other method known in the art for mechanically driving the opening of the arms of a clasp. Rotational driver  1510  and screw  1511  may be re-engaged by opening clasp  1513  and pushing rotational driver  1510  into screw  1511  again. 
       FIGS. 16A-B  illustrate a side-view and top-view of a rotational driver that can be used to rotate a nut over a strut in an appropriate direction.  FIG. 16A  illustrates a side-view of rotational driver  1608  engaged and disengaged from strut  1605 .  FIG. 16B  illustrates a top-view of rotational driver  1608  disengaged from strut  1605 . Strut  1605  has threads cut along it. Strut  1605  may be, for example, any of the struts described in this disclosure (see, e.g.,  FIGS. 6A-L ). The threads are configured such that the rotation of nut  1601  moves nut  1601  along (e.g., axially) strut  1605 . Rotational driver  1608  comprises cog  1607  that is configured to engage nut  1601 . Small bent wire  1602  or a similar mechanism may be used as a counter force to keep nut  1601  and rotational driver  1608  engaged by hooking into space  1609  of strut  1605 . 
     During delivery, small bent wire  1602  is hooked into space  1609  and nut  1601  and rotational driver  1608  are engaged. Rotational driver  1608  and nut  1601  are pushed together so that they are locked together, and space  1609  and cog  1607  are positioned in tubular cover  1610 . In this state, rotational force may be applied through rotational driver  1608  to rotate nut  1601 , thereby moving it along (e.g., axially) strut  1605 . The rotation of rotational driver  1608  may be controlled and/or supplied from the external handle of the delivery catheter. Nut  1601  and cog  1607  may be disengaged by pulling them apart and disconnecting small bent wire  1602  from space  1609 . Rotational driver  1608  and strut  1605  may also be re-engaged by hooking small bent wire  1602  and space  1609  together, and pushing rotational driver  1608  and strut  1605  together. 
       FIGS. 17A-B  illustrate an example push-slider mechanism that may be used to manipulate an implant.  FIG. 17A  illustrates a side-view of push tube  1702  engaged and disengaged from strut  1700  respectively.  FIG. 17B  illustrates a top-view of push tube  1702  disengaged from strut  1700 . 
     Push tube  1702  may be used to push clip  1701  or other adjustable restraints down strut  1700 . The movement (e.g., axial movement) of push clip  1701  may draw the arms  1705  and  1707  of strut  1700  closer to one another, which in turn may pull the anchors attached to arms  1705  and  1707  of strut  1700  together. Where the anchors are attached to the tissue surrounding and/or including a mitral valve, the tissue is similarly pulled together. Push clip  1701  may have an outer diameter and an inner diameter with a single or a plurality of fingers protruding inward creating a cog that interacts with the ridges of arms  1705  and  1707  to limit motion in one direction. The shape of push clip  1701  may be non-circular and/or an oval to better conform to the shape of strut  1700 . Push clip  1701  may be constructed from stainless steel, Nickel-Titanium, Cobalt-Chromium, Pyrolytic Carbon, Nitinol, polymer materials (e.g., PEEK), and/or other suitable implant materials. A counter force may be supplied from wire  1703 , which hooks into space  1708  of strut  1700  and holds push tube  1702  to strut  1700 , thereby connecting them. During delivery, wire  1703  may be placed in space  1708 , and push tube  1702  and clip  1701  may be pushed together. Push tube  1702  and clip  1701  may be disengaged by unhooking wire  1703  from space  1708  and pulling push tube  1702  away from clip  1701  and strut  1700 . They may be re-engaged by hooking wire  1703  into space  1708  and pushing push tube  1702  into clip  1701 . 
       FIG. 18A  illustrates an example delivery system for an implant having forward (distal) facing anchors for entry from the left atrium, or for entry from a femoral vein and a transseptal puncture. The force for engaging implant  1811  into the heart tissue would be, in some cases, a forward or pushing mechanism to engage the anchors of implant  1811 . Included in the delivery system is guidewire  1810 . Sheath  1812  may cover implant  1811  before it is expanded for delivery and positioning. The distal end of sheath  1812  may include a pre-shaped curve to match the anatomical needs of the patient. The distal end may also have an active ability to steer, curve, and/or rotate for delivery and/or positioning. Handle  1813  may allow for accurate positioning of implant  1811  and transmission of forces to implant  1811 . Additionally, handle  1813  may allow for adjustments of implant  1811  through driver mechanisms, including any driver mechanism described in this disclosure. For example, in some embodiments, handle  1813  may have rotational drivers  1814 , which may be any rotational driver described in this disclosure. Implant  1811  may also be, for example, any implant described in this disclosure, including ones that have sinusoidal, diamond-patterned, and/or tapered struts. 
       FIG. 18B  illustrates an example delivery system for an implant having proximal facing anchors for entry from a left ventricle (e.g., a transapical entry). Implant  1801  may pass through a left ventricle into the left atrium, and be exposed by a removal of sheath  1802  at the distal end. The removal of sheath  1802  may allow implant  1801  to expand or to be forcefully expanded by connection arms or other expansion mechanisms such as a balloon and/or any mechanism described in this disclosure for example. For example, implant  1801  may be connected to connection arms that shape implant  1801  to a diameter and/or shape to match the patient&#39;s mitral valve anatomy. As another example, a plurality of nuts (e.g., nut  602  ( FIG. 6A ), nut  680  ( FIG. 6J ), nut  691  (FIG.  6 K)), clips (e.g., clip  634  ( FIG. 6D ) and clip  671  (FIG.  6 I)), rings (e.g., locking ring  672  (FIG.  6 I)), and/or cables (e.g., cable  640  ( FIG. 6F )) may be positioned as to compress the size and/or shape of implant  1801 , or any implant of this disclosure, while it is being delivered. The nuts, clips, and/or cables may be repositioned after implant  1801  has been delivered in order to expand implant  1801 . 
     Handle  1803  may allow for adjustments of implant  1801  through driver mechanisms, including any driver mechanism described in this disclosure. Because of the proximal facing anchors of implant  1801 , a screw-and-clip mechanism, similar to the mechanisms illustrated in  FIG. 6D  and/or  FIG. 6I , may be suited to gather the struts of implant  1801  together. The screw-and-clip mechanism may be actuated by rotational drivers  1804  located at the proximal end of handle  1803 . Rotational drivers  1804  may also implement any of the other actuating mechanisms described in this disclosure. 
       FIG. 19  illustrates a close-up of an example implant with proximal facing anchors with screw-and-clip mechanisms to adjust the shape and/or size of the implant. For example, implant  1906  has strut  1903  that is connected to anchors  1904  and  1907 . Strut  1903  has clip  1902 , which is configured to gather the arms of strut  1903  closer together as clip  1902  advances along strut  1903 . As the arms of strut  1903  gather together, so do anchors  1904  and  1907 , and any tissue to which anchors  1904  and  1907  may be embedded. Attached to strut  1903  is threaded boss  1901  (which may be a screw retainer) to drive screw  1900  and clip  1902  up and down strut  1903 . For example, loosening screw  1900  relative to boss  1901  moves clip  1902  downward, pulling the arms of strut  1903  together. Other struts of implant  1906  may have similar configurations and may be adjusted in coordination or independently. 
       FIG. 20  illustrates a close-up of the implant of  FIG. 19  where the screw-and-clip mechanisms reduce the diameter of the implant. The actuation of the clips (e.g., clip  1902 ) may occur after anchors (e.g., anchors  1904  and  1907 ) are engaged into the tissue surrounding and/or including a mitral valve. The clips may also be in a downward position while implant  1906  is being delivered to a left atrium. The actuation of the clips may be driven by rotational drivers  1905 , which may be controlled outside the body at the proximal end of the delivery system (see, e.g., rotational drivers  1814  ( FIG. 18A ) and rotational drivers  1804  ( FIG. 18B )). Rotational drivers  1905  may connect to the screws (e.g., screw  1900 ) of implant  1906 . In some embodiments, rotational drivers  1905  may also serve as connection arms that connect implant  1906  to a delivery catheter. The adjustment of the rotational drivers  1905  could also be reversed if the regurgitant flow of the mitral valve was altered negatively or added to the regurgitant flow volume. 
       FIG. 21  illustrates a close-up of an example implant with distal facing anchors and screw-and-clip mechanisms to adjust the shape and/or size of the implant. Implant  2107  has a plurality of distal facing anchors, such as anchors  2105 . The size and/or shape of implant  2107  may be adjusted in a similar way as implant  1906  illustrated in  FIGS. 19 and 20  and use a screw-and-clip mechanism similar to those depicted in  FIG. 6D  and  FIG. 6I . For example, rotational drivers  2101  connect to and deliver rotational force to the screws of implant  2107 , including screw  2103 . In this way, clip  2106  may be moved along strut  2104  by a rotational force from rotational drivers  2101 . The rotational force may be translated to screw  2103  through boss  2102  (which may be a screw retainer). Similar to the implant illustrated in  FIG. 20 , the actuation may be controlled outside the body at the proximal end of the delivery system (see, e.g., rotational drivers  1814  ( FIG. 18A ) and rotational drivers  1804  ( FIG. 18B )). The movement of the clips may be used to increase or decrease the size of implant  2107 . In some embodiments, rotational drivers  2101  may also serve as connection arms that connect implant  2107  to a delivery catheter. 
       FIG. 22A  illustrates a close-up of an example implant with proximal facing anchors and connection arms connected to the implant. Implant  2202  has similar screw-and-clip mechanisms as  FIG. 19 . Additionally, connection arms  2200  are connected to implant  2202  to allow for device expansion during delivery. Connection arms  2200  can be pre-shaped to make implant  2202  into a circular, oval, and/or elliptical shape to match the patient&#39;s mitral valve anatomy. Connection arms  2200  are designed to connect a handle and delivery system to implant  2202  for precise implant placement. 
     Connection arms  2200  may connect to implant  2202  by rotational screws that engage implant  2202 . Connection arms  2200  may also connect to implant  2202  by tubular elements with wires passing through them. For example, tubular element  2203  has connection wire  2201  passing through it. Wire  2201  may then additionally pass through a receiver hole in implant  2202  to secure tubular element  2203  and the receiver hole together (see, e.g.,  FIG. 6C ). 
     Once wire  2201  is retracted, tubular element  2203  becomes free to disengage from implant  2202 . Similarly, some or all of the tubular members of connection arms  2200  may be disengaged from implant  2202 . Tubular element  2203  can be constructed from materials including stainless steel, Nickel-Titanium, Cobalt-Chromium, Pyrolytic Carbon, Nitinol, polymer materials (e.g., PEEK), and/or other suitable implant materials. In some cases, where connection arms  2200  are pre-shaped, they provide a passive force expanding implant  2202  outward and controlling the shape of implant  2202 . 
       FIG. 22B  illustrates an example implant with proximal facing anchors and connection arms attaching the implant to a delivery system. Tip  2202  of delivery system  2206  is shown in the left image in a distal position. If pulled proximally (as in the right figure), tip  2202  may push connection arms  2205  apart from each other as tip  2202  is disposed between connection arms  2205 . This action may expand implant  2207  to a larger diameter and/or shape for embedding into the tissue surrounding and/or including a mitral valve. Additionally, it should be appreciated that the expanded shape of implant  2207  may reflect the shape of tip  2202 . Accordingly, tip  2202  may have a round, oval, elliptical and/or amorphous shape in order to shape connection arms  2205  and implant  2207  to better reflect the desired shape of the mitral valve when tip  2202  is pulled proximally. The disengagement of connection arms  2205  and tip  2202  from implant  2207  may allow implant  2207  to reduce in diameter through passive or active forces, as described in this disclosure. 
       FIG. 23  illustrates example anchor configurations of various shapes. Anchor  2300  has symmetrical barbs on either side of it. Anchor  2301  is asymmetrical, and has a barb on only one side, but also has approximately equal width to anchor  2300 . The more prominent extension of the single barb may increase tissue engagement depth. Because anchor  2301  has approximately the same width as anchor  2300 , in some cases it may provide a lower insertion force and have a bias to one side for lateral movement when a plurality of anchors such as anchor  2301  are moved towards one another. 
     Additionally, the order in which anchors are embedded and/or the sequencing of the various anchors of an implant may also vary as desired. For example, formation  2305  has anchors  2307  and  2306  that have opposing barbs that face each other. The implant may further sequence its anchors such that each anchor of the implant has an anchor with a barb facing it in a similar formation as formation  2305 . 
     In some embodiments, an implant may also not embed all anchors into the tissue surrounding and/or including a mitral valve simultaneously. For example, every other anchor may be embedded first and/or only anchors with barbs facing in one direction may be embedded first (e.g., only anchors having barbs facing the same direction as anchor  2306  may be embedded first). The embedded anchors could first be adjusted by initial adjustments of the implant. The anchors that were not first embedded could then be embedded to finish the adjustment of the implant. Synchronizing the embedding of the anchors in this way may provide better securement of the implant to the tissue surrounding and/or including a mitral valve. The anchors may also later by cinched to push facing anchors (e.g., anchors  2306  and  2307 ) closer together for a better hold. 
     Similar synchronizing may be applied to implants with other anchor formations (e.g., implant  2302 ) and/or implants having any size and/or shape including those as described in this disclosure. The degree of synchronizing and/or sequencing could be selected and varied depending upon the operator&#39;s intent and the patient&#39;s need and/or disease state. 
       FIG. 24  illustrates an example implant with anchors covered with slideable elements. Independent activation or exposure of the anchors of an implant may occur by using multiple ribbons configured to push or pull slideable elements (e.g., anchor covers) that cover the anchors. For example, ribbons  2406  may extend from collar  2400  to connect to slideable elements of implant  2405  in order to control the slideable elements. The slideable elements may cover the anchors of the implant. For example, slideable element  2403  covers anchor  2401 . Ribbons  2406  may also aid in maintaining lateral rigidity and increasing inward flexibility of implant  2405  in conjunction with connection arms  2407 . Delivery catheter  2404  may be used to guide implant  2405  into position. 
     In some cases, wires may pass through implant  2405  and ribbons  2406  in order to connect them together. The wires may be withdrawn in order to separate ribbons  2406  from implant  2405  in manners similar to others described in this disclosure (see, e.g.,  FIG. 6C ). Ribbons  2406  could be constructed of material(s) including stainless steel, Nickel-Titanium, Cobalt-Chromium, Pyrolytic Carbon, Nitinol, polymer materials (e.g., PEEK), and/or other suitable implant materials. Ribbons  2406  may have a pre-shaped form or a simple flat shape that can be forced open and closed radially.  FIG. 25  illustrates the example implant from  FIG. 24  with anchors exposed and ready for implantation. 
       FIGS. 26A-C  illustrate an example anchor that has a helical shape and a sharp distal end that can be rotated through an extension of an implant strut to engage the tissue surrounding and/or including a mitral valve.  FIG. 26A  illustrates a side-view of example anchor  2602 , which has a helical shape.  FIG. 26B  illustrates a front-view, and  FIG. 26C  illustrates an angled view of the same anchor  2602 . 
     Strut  2600  may have extension  2601 , which comprises of holes. The holes (e.g., hole  2603 ) of extension  2601  may be configured such that anchor  2602  may pass through the holes with its helical shape. The helical shape of anchor  2602  may spiral through the holes, adjustably connecting to the tissue surrounding and/or including a mitral valve. One having ordinary skill the art should appreciate that anchor  2602  may be extended downward or retracted upward by rotating it such that the coils of anchor  2602  pass through the holes of extension  2601 . 
     Anchor  2602  may be a screw-form constructed of material(s) including stainless steel, Nickel-Titanium, Cobalt-Chromium, Pyrolytic Carbon, Nitinol, polymer materials (e.g., PEEK), and/or other suitable implant materials. The cross-sectional diameter of anchor  2602  may measure in some embodiments between 0.010 and 0.025 inches and be coiled at a pitch of between 20 and 60 coils per inch, measuring about 0.03 to 0.08 inches in outer diameter. The overall length of anchor  2602  may measure, for example, about 0.2 to 0.5 inches. 
       FIG. 27  illustrates an example anchor that has a helical shape that can be rotated through an implant strut to engage the tissue surrounding and/or including a mitral valve. Anchor  2701  is similarly constructed to anchor  2602  of  FIG. 26A-C . Strut  2700  may have holes  2702 , which may be patterned in diagonal and/or oblique positions such that anchor  2701  may pass through them. Again, anchor  2701  may be extended downward or retracted upward by rotating it such that the coils of anchor  2701  pass through holes  2702 . 
       FIG. 28  illustrates an example implant with anchors that have a helical shape. Implant  3000  is in a delivery state that is smaller in diameter than its normal unconstrained state, allowing for its advancement into a left atrium via a delivery catheter. In some embodiments, implant  3000  may be still attached to a delivery catheter and the helical-shaped anchors of implant  3000  may be still in their retracted positions. For example, anchor  3003  is helical-shaped and passes through holes  3004 , which may be similar to holes  2702  ( FIG. 27 ). As illustrated, anchor  3003  is in a retracted position such that it does not extend far beyond holes  3004 . Anchor  3003  has cap  3002 , which may be connected to a rotational driver. The rotational driver may comprise the rotational drivers illustrated in  FIGS. 13 ,  14 ,  15 , and/or  16 A-B, and/or any rotational driver described in this disclosure for example. Implant  3000  also has nuts, such as nut  3001 , which are located on the struts of implant  3000  to adjust the size and/or shape of implant  3000 . Nut  3001  may be similar to nut  602  illustrated in  FIGS. 6A-B  and may be rotated by any rotational drivers of this disclosure, including the rotational drivers illustrated in  FIGS. 13 ,  14 ,  15 , and/or  16 A-B. Upon delivery to a left atrium and/or after implant  3000  has been expanded, anchor  3003  may be rotated such that it extends downward to engage the tissue surrounding and/or including a mitral valve. 
       FIG. 29  illustrates the example implant of  FIG. 28  in a radially expanded state. Implant  3000  has been expanded to engage the tissue surrounding and/or including a mitral valve. Anchors, such as anchor  3003 , are still positioned in the retracted position. 
       FIG. 30  illustrates the example implant of  FIG. 29  where the anchors have been extended. For example, anchor  3003  has been rotated such that it has extended downward. In this way, it may extend into the tissue surrounding and/or including a mitral valve. Each anchor may be rotated individually or connected to one another for simultaneous extension. 
       FIG. 31  illustrates the example implant of  FIG. 30  where the example implant has been contracted. Nuts, such as nut  3001 , have been advanced along their respective struts in order to reshape implant  3000 . Because anchors, such as anchor  3003 , have been extended to engage the tissue surrounding and/or including a mitral valve, the reshaping of implant  3000  further reshapes that mitral valve. 
     One having ordinary skill in the art should appreciate that anchors having helical shapes may be adapted to any of the implants and/or mechanisms described in this disclosure. It should also be appreciated that implant  3000  may be adapted to use any of the mechanisms for adjusting size and/or shape described in this disclosure. For example, implant  3000  may use a plurality of adjustable restraints, including nuts (e.g., nut  602  ( FIG. 6A ), nut  680  ( FIG. 6J ), nut  691  (FIG.  6 K)), clips (e.g., clip  634  ( FIG. 6D ) and clip  671  (FIG.  6 I)), rings (e.g., locking ring  672  (FIG.  6 I)), and/or cables (e.g., cable  640  ( FIG. 6F )). These adjustable restraints may be used to adjust the size and/or shape of implant  3000  within a working range. In some embodiments, cables may also be adapted to connect to caps, such as cap  2002 . In this way, the cables may provide further adjustment of the size and/or shape of implant  3000 . 
     In some embodiments, a replacement prosthetic heart valve may be operatively coupled to any implant described in this disclosure. The valve may be positioned within the mitral, aortic, or other valve annulus and disposed axially within the central lumen of the implant body, and in some cases in a minimally-invasive procedure such as a transcatheter mitral or aortic valve replacement procedure. In some embodiments, the valve may include a stent frame operably attached to prosthetic leaflet(s) configured to coapt the valve. For example, the replacement prosthetic valve may comprise a nitinol support frame having diamond-patterned or other cells, wherein the frame is configured to support the leaflets of the mitral valve. In some embodiments, the replacement prosthetic valve may comprise a bioprosthetic valve leaflets, such as those derived from bovine, equine, or porcine tissue, such as pericardial tissue for example, or any tissue derived from or obtained from an animal. In other embodiments, the valve may be any valve replacement known in the art. In some embodiments, the implants as described herein can be utilized as a “docking station” or scaffold to temporarily or permanently be operably connected to, for example, a variety of physiologic sensors measuring pressure, hemoglobin, oxygen, carbon dioxide, and the like across the valve, and other diagnostic and therapeutic devices, including drug delivery/infusion devices. 
     The implant may comprise connectors that allow it to connect to the valve. For example, the implant may comprise hooks, clasps, tangs, clips, fasteners, and/or cogs positioned radially inward in order to clasp, hold, clip, and/or otherwise interact with the replacement prosthetic valve. In some cases, the hooks, claps, tangs, clips, fasteners, and/or cogs may be positioned radially inward at an angle (e.g., +/−0, 10, 20, 30, 40, 50, 60, 70, 80, and/or 90 degrees, and/or any angle between any two of the aforementioned angles). The hooks, clasps, tangs, clips, fasteners, and/or cogs may also be positioned distally, proximally, and/or at an angle between distally and proximally (e.g., +/−0, 10, 20, 30, 40, 50, 60, 70, 80, and/or 90 degrees, and/or any angle between any two of the aforementioned angles) in order to clasp, hold, clip, and/or otherwise interact with the replacement prosthetic valve. In some embodiments, the implant may also comprise cable(s), wherein the cable(s) are configured to hold the implant and the replacement prosthetic valve in place. For example, one end of an adjustable cable (e.g., a cable that may be lengthened and/or shortened using any mechanism described in this disclosure) may be tied to the implant (e.g., in a receiver hole and/or strut of the implant) using a knot. The other end of the cable may be tied to the replacement prosthetic valve (e.g., to a diamond-patterned cell and/or receiver hole) using a knot. In other cases, a cable may pass through the replacement prosthetic valve and the implant, and the ends of the cable may be tied together to hold the valve and the implant together. For example, a cable may pass axially through the frame of a diamond-patterned cell and/or a receiver hole of the replacement prosthetic valve, and pass axially through a strut and/or receiver hole of the implant. The ends of the cable may be tied together to secure the implant and the replacement prosthetic valve together. In any of the aforementioned ways, the implant may hold the valve in place and secure its placement. As such, the implant may act as a docking station for the replacement prosthetic valve. In some cases, the replacement prosthetic valve and the implant may behave functionally as a replacement prosthetic valve with anchors for securement. 
     The valve may be delivered to the mitral valve before, after, or at the same time as any implant described in this disclosure. For example, the replacement prosthetic valve may be delivered independently of the implant through one of several methods, including transfemoral, transapical, subclavian, and direct aortic implantation. The replacement prosthetic valve may then be placed within the implant, or the implant may be place around the replacement prosthetic valve. For example, in some cases where the replacement prosthetic valve is positioned in the valve region before the implant, the implant may expand so that the replacement prosthetic valve may be medially positioned within the implant&#39;s frame. Once the replacement prosthetic valve is medially positioned within the frame of the implant, the implant may contract around the replacement prosthetic valve, causing the hooks, clasps, tangs, clips, fasteners, and/or cogs positioned on the implant to clasp, hold, clip, and/or otherwise interact with the replacement prosthetic valve. As another example, the implant may already be positioned in an expanded configuration in the heart before the valve is positioned in the same or a different procedure, on the same day or a later date. The valve may then pass axially through the central lumen of the implant, and be positioned in the mitral, aortic, or other valve via a percutaneous, transapical, transseptal, or other approach, some of which are described in the present specification. The implant may then contract around the valve, causing the hooks, clasps, tangs, clips, fasteners, and/or cogs positioned on the implant to clasp, hold, clip, and/or otherwise interact with the prosthetic replacement valve. Non-limiting examples of valves that can be delivered or modified for delivery and anchored with the implants described herein include the FORTIS or SAPIEN valves from Edwards Lifesciences, the TIARA valve from Neovasc, and the COREVALVE and ENGAGER valves from Medtronic, Inc. 
     In some embodiments, the prosthetic replacement valve may also be delivered at the same time as the implant. For example, the valve may be coupled to the same delivery catheter (e.g., delivery catheter  301  ( FIG. 3 )) and/or delivery system as the implant. In some cases, the valve may be placed coaxially within the implant such that implant and valve may be deployed at the same time. In other cases, the valve may be placed off-axis, but still disposed within the implant&#39;s frame during deployment. 
       FIG. 32  illustrates an example replacement prosthetic heart valve operably coupled to an example implant. Implant  3200  has been collapsed around valve  3201 . Valve  3201  is a prosthetic valve comprising anterior leaflet  3202  and posterior leaflet  3204 . Implant  3200  has a plurality of connectors (e.g., connector  3203 ) that connects implant  3200  to valve  3201 . Connector  3203  may be a hook, clasp, tang, clip, fastener, and/or cog positioned on implant  3200  to clasp, hold, clip, and/or otherwise interact with valve  3201 . 
     Various other modifications, adaptations, and alternative designs are of course possible in light of the above teachings. For example, while generally described in conjunction with resizing and/or reshaping of a mitral valve annulus, in some embodiments, aortic, tricuspid, pulmonic, or venous valves can also be altered using devices and methods as disclosed herein. Other vascular and non-vascular body lumens such as, for example, the esophagus, stomach, intestines, ureters, fallopian tubes, and other lumens can also be altered using devices and methods as disclosed herein. Therefore, it should be understood at this time that within the scope of the appended claims the invention may be practiced otherwise than as specifically described herein. It is contemplated that various combinations or subcombinations of the specific features and aspects of the embodiments disclosed above may be made and still fall within one or more of the inventions. Further, the disclosure herein of any particular feature, aspect, method, property, characteristic, quality, attribute, element, or the like in connection with an embodiment can be used in all other embodiments set forth herein. Accordingly, it should be understood that various features and aspects of the disclosed embodiments can be combined with or substituted for one another in order to form varying modes of the disclosed inventions. Thus, it is intended that the scope of the present inventions herein disclosed should not be limited by the particular disclosed embodiments described above. Moreover, while the invention is susceptible to various modifications, and alternative forms, specific examples thereof have been shown in the drawings and are herein described in detail. It should be understood, however, that the invention is not to be limited to the particular forms or methods disclosed, but to the contrary, the invention is to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the various embodiments described and the appended claims. Any methods disclosed herein need not be performed in the order recited. The methods disclosed herein include certain actions taken by a practitioner; however, they can also include any third-party instruction of those actions, either expressly or by implication. For example, actions such as “inserting an adjustable valvular ring proximate an annulus” includes “instructing the inserting of an adjustable valvular ring proximate an annulus.” The ranges disclosed herein also encompass any and all overlap, sub-ranges, and combinations thereof. Language such as “up to,” “at least,” “greater than,” “less than,” “between,” and the like includes the number recited. Numbers preceded by a term such as “approximately”, “about”, and “substantially” as used herein include the recited numbers (e.g., about 10%=10%), and also represent an amount close to the stated amount that still performs a desired function or achieves a desired result. For example, the terms “approximately”, “about”, and “substantially” may refer to an amount that is within less than 10% of, within less than 5% of, within less than 1% of, within less than 0.1% of, and within less than 0.01% of the stated amount.