Patent Publication Number: US-2020281718-A1

Title: Low crossing profile delivery catheter for cardiovascular prosthetic implant

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application is a continuation of U.S. patent application Ser. No. 13/110,780, filed on May 18, 2011, which claims the priority benefit to U.S. Provisional No. 61/346,390 filed May 19, 2010 and U.S. Provisional No. 61/411,862 filed Nov. 9, 2010, the entireties of which are hereby incorporated by reference herein. 
    
    
     BACKGROUND OF THE INVENTION 
     Field of the Invention 
     The present invention relates to medical methods and devices, and, in particular, to a low crossing profile delivery catheter for percutaneously implanting a cardiovascular implant having a formed-in-place support structure. 
     Description of the Related Art 
     According to recent estimates, more than 79,000 patients are diagnosed with aortic and mitral valve disease in U.S. hospitals each year. More than 49,000 mitral valve or aortic valve replacement procedures are performed annually in the U.S., along with a significant number of heart valve repair procedures. 
     The circulatory system is a closed loop bed of arterial and venous vessels supplying oxygen and nutrients to the body extremities through capillary beds. The driver of the system is the heart providing correct pressures to the circulatory system and regulating flow volumes as the body demands. Deoxygenated blood enters heart first through the right atrium and is allowed to the right ventricle through the tricuspid valve. Once in the right ventricle, the heart delivers this blood through the pulmonary valve and to the lungs for a gaseous exchange of oxygen. The circulatory pressures carry this blood back to the heart via the pulmonary veins and into the left atrium. Filling of the left atrium occurs as the mitral valve opens allowing blood to be drawn into the left ventricle for expulsion through the aortic valve and on to the body extremities. When the heart fails to continuously produce normal flow and pressures, a disease commonly referred to as heart failure occurs. 
     Heart failure simply defined is the inability for the heart to produce output sufficient to demand. Mechanical complications of heart failure include free-wall rupture, septal-rupture, papillary rupture or dysfunction aortic insufficiency and tamponade. Mitral, aortic or pulmonary valve disorders lead to a host of other conditions and complications exacerbating heart failure further. Other disorders include coronary disease, hypertension, and a diverse group of muscle diseases referred to as cardiomyopothies. Because of this syndrome establishes a number of cycles, heart failure begets more heart failure. 
     Heart failure as defined by the New York Heart Association in a functional classification.
         I. Patients with cardiac disease but without resulting limitations of physical activity. Ordinary physical activity does not cause undue fatigue, palpitation, dyspnea, or anginal pain.   II. Patient with cardiac disease resulting in slight limitation of physical activity. These patients are comfortable at rest. Ordinary physical activity results in fatigue, palpitation, dyspnea, or anginal pain.   III. Patients with cardiac disease resulting in marked limitation of physical activity. These patients are comfortable at rest. Less than ordinary physical activity causes fatigue palpitation, dyspnea, or anginal pain.   IV. Patients with cardiac disease resulting in inability to carry on any physical activity without discomfort. Symptoms of cardiac insuffiency or of the anginal syndrome may be present even at rest. If any physical activity is undertaken, discomfort is increased.       

     There are many styles of mechanical valves that utilize both polymer and metallic materials. These include single leaflet, double leaflet, ball and cage style, slit-type and emulated polymer tricuspid valves. Though many forms of valves exist, the function of the valve is to control flow through a conduit or chamber. Each style will be best suited to the application or location in the body it was designed for. 
     Bioprosthetic heart valves comprise valve leaflets formed of flexible biological material. Bioprosthetic valves or components from human donors are referred to as homografts and xenografts are from non-human animal donors. These valves as a group are known as tissue valves. This tissue may include donor valve leaflets or other biological materials such as bovine pericardium. The leaflets are sewn into place and to each other to create a new valve structure. This structure may be attached to a second structure such as a stent or cage or other prosthesis for implantation to the body conduit. 
     Implantation of valves into the body has been accomplished by a surgical procedure and has been attempted via percutaneous method such as a catheterization or delivery mechanism utilizing the vasculature pathways. Surgical implantation of valves to replace or repair existing valves structures include the four major heart valves (tricuspid, pulmonary, mitral, aortic) and some venous valves in the lower extremities for the treatment of chronic venous insufficiency. Implantation includes the sewing of a new valve to the existing tissue structure for securement. Access to these sites generally include a thoracotomy or a sternotomy for the patient and include a great deal of recovery time. An open-heart procedure can include placing the patient on heart bypass to continue blood flow to vital organs such as the brain during the surgery. The bypass pump will continue to oxygenate and pump blood to the body&#39;s extremities while the heart is stopped and the valve is replaced. The valve may replace in whole or repair defects in the patient&#39;s current native valve. The device may be implanted in a conduit or other structure such as the heart proper or supporting tissue surrounding the heart. Attachments methods may include suturing, hooks or barbs, interference mechanical methods or an adhesion median between the implant and tissue. 
     Although valve repair and replacement can successfully treat many patients with valvular insufficiency, techniques currently in use are attended by significant morbidity and mortality. Most valve repair and replacement procedures require a thoracotomy, usually in the form of a median sternotomy, to gain access into the patient&#39;s thoracic cavity. A saw or other cutting instrument is used to cut the sternum longitudinally, allowing the two opposing halves of the anterior or ventral portion of the rib cage to be spread apart. A large opening into the thoracic cavity is thus created, through which the surgical team may directly visualize and operate upon the heart and other thoracic contents. Alternatively, a thoracotomy may be performed on a lateral side of the chest, wherein a large incision is made generally parallel to the ribs, and the ribs are spread apart and/or removed in the region of the incision to create a large enough opening to facilitate the surgery. 
     Surgical intervention within the heart generally requires isolation of the heart and coronary blood vessels from the remainder of the arterial system, and arrest of cardiac function. Usually, the heart is isolated from the arterial system by introducing an external aortic cross-clamp through a sternotomy and applying it to the aorta to occlude the aortic lumen between the brachiocephalic artery and the coronary ostia. Cardioplegic fluid is then injected into the coronary arteries, either directly into the coronary ostia or through a puncture in the ascending aorta, to arrest cardiac function. The patient is placed on extracorporeal cardiopulmonary bypass to maintain peripheral circulation of oxygenated blood. 
     Since surgical techniques are highly invasive and in the instance of a heart valve, the patient must be put on bypass during the operation, the need for a less invasive method of heart valve replacement has long been recognized. At least as early as 1972, the basic concept of suturing a tissue aortic valve to an expandable cylindrical “fixation sleeve” or stent was disclosed. See U.S. Pat. No. 3,657,744 to Ersek. Other early efforts were disclosed in U.S. Pat. No. 3,671,979 to Moulopoulos and U.S. Pat. No. 4,056,854 to Boretos, relating to prosthetic valves carried by an expandable valve support delivered via catheter for remote placement. More recent iterations of the same basic concept were disclosed, for example, in patents such as U.S. Pat. Nos. 5,411,552, 5,957,949, 6,168,614, and 6,582,462 to Anderson, et al., which relate generally to tissue valves carried by expandable metallic stent support structures which are crimped to a delivery balloon for later expansion at the implantation site. 
     In each of the foregoing systems, the tissue or artificial valve is first attached to a preassembled, complete support structure (some form of a stent) and then translumenally advanced along with the support structure to an implantation site. The support structure is then forceably enlarged or allowed to self expand without any change in its rigidity or composition, thereby securing the valve at the site. 
     Despite the many years of effort, and enormous investment of entrepreneurial talent and money, no stent based heart valve system has yet received regulatory approval, and a variety of difficulties remain. For example, stent based systems have a fixed rigidity even in the collapsed configuration, and have inherent difficulties relating to partial deployment, temporary deployment, removal and navigation. 
     Thus, a need remains for improvements over the basic concept of a stent based prosthetic valve. As disclosed herein a variety of significant advantages may be achieved by eliminating the stent and advancing the valve to the site without a support structure. Only later, the support structure is created in situ such as by inflating one or more inflatable chambers to impart rigidity to an otherwise highly flexible and functionless subcomponent. 
     SUMMARY OF THE INVENTION 
     One aspect of the present invention comprises a delivery catheter for deploying a cardiovascular prosthetic implant using a minimally invasive procedure. The delivery catheter comprises an elongate, flexible catheter body having a proximal end and a distal end. The distal portion of the catheter has an outer diameter of 18 French or less. A cardiovascular prosthetic implant is positioned at the distal end of the catheter body. The cardiovascular prosthetic implant comprises an inflatable cuff and a tissue valve having a thickness of at least about 0.011 inches coupled to the inflatable cuff. At least one link is provided between the catheter body and the cardiovascular prosthetic implant 
     Another aspect of the present invention comprises a method of deploying a cardiovascular prosthetic implant. The method includes translumenally advancing a catheter having a distal portion with a diameter of 18 French and carrying a cardiovascular prosthetic implant with a tissue valve having a thickness of at least about 0.011 inches to a position proximate a native valve of a patient. The cardiovascular prosthetic implant comprises an inflatable cuff, a tissue valve coupled to the inflatable cuff. The inflatable cuff is inflated fully with a hardenable inflation media. The catheter is removed from the patient, leaving the hardenable inflation media in the cardiovascular prosthetic implant within the patient. 
     Another aspect of the present invention comprises a delivery catheter for deploying a cardiovascular prosthetic implant using a minimally invasive procedure. The delivery catheter comprises an elongate, flexible catheter body having a proximal end and a distal end, wherein the distal end has an outer diameter of 18 French or less. A cardiovascular prosthetic implant is positioned at the distal end of the catheter body. The cardiovascular prosthetic implant comprises a support structure and a tissue valve having a thickness of at least about 0.011 inches coupled to the support structure 
     Another aspect of the present invention comprises a method of deploying a cardiovascular prosthetic implant. The method comprises translumenally advancing a catheter having a distal portion with a diameter of 18 French and carrying a cardiovascular prosthetic implant with a tissue valve having a thickness of at least about 0.011 inches to a position proximate a native valve of a patient. The cardiovascular prosthetic implant is deployed within the patient and the catheter is removed from the patient. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a cross-sectional schematic view of a heart and its major blood vessels. 
         FIG. 2A  is a partial cut-away view a left ventricle and aortic with an prosthetic aortic valve implant according to one embodiment of the present invention positioned therein. 
         FIG. 2B  is a side view of the implant of  FIG. 2A  positioned across a native aortic valve. 
         FIG. 3A  is a front perspective view of the implant of  FIG. 2B . 
         FIG. 3B  is a front perspective view of an inflatable support structure of the implant of  FIG. 3A . 
         FIG. 3C  is a cross-sectional side view of the implant of  FIG. 3A . 
         FIG. 3D  is an enlarged cross-sectional view of an upper portion of  FIG. 3C . 
         FIG. 4  is a cross-sectional view of the connection port and the inflation valve in the implant of  FIG. 3B . 
         FIG. 5A  is a side perspective view of a deployment catheter with retracted implant. 
         FIG. 5B  is a side perspective view of the deployment catheter of  FIG. 5A  with the implant outside of the outer sheath jacket. 
         FIG. 5C  is a side perspective view of the position-and-fill lumen (PFL), which is a component of the deployment catheter of  FIGS. 5A and 5B . 
         FIG. 6  is a cross-sectional view taken through line A-A of  FIG. 5B . 
         FIG. 7  is a side perspective view of a loading tool base. 
         FIGS. 8A-C  illustrate time sequence steps of partially deploying and positioning an artificial valve implant. 
         FIGS. 9A-E  illustrates time sequence steps of deploying, testing and repositioning an artificial valve implant. 
         FIGS. 10A-C  illustrates time sequence steps of deploying and withdrawing an artificial valve implant. 
         FIG. 11  is a side perspective view of an embodiment of recovery catheter for retrieving the implant in the patient. 
         FIG. 12  is a side perspective view of a method of compressing the implant of  FIGS. 3A-B . 
     
    
    
     DETAILED DESCRIPTION OF THE EMBODIMENTS 
       FIG. 1  is a schematic cross-sectional illustration of the anatomical structure and major blood vessels of a heart  10 . Deoxygenated blood is delivered to the right atrium  12  of the heart  10  by the superior and inferior vena cava  14 ,  16 . Blood in the right atrium  12  is allowed into the right ventricle  18  through the tricuspid valve  20 . Once in the right ventricle  18 , the heart  10  delivers this blood through the pulmonary valve  22  to the pulmonary arteries  24  and to the lungs for a gaseous exchange of oxygen. The circulatory pressures carry this blood back to the heart via the pulmonary veins  26  and into the left atrium  28 . Filling of the left atrium  28  occurs as the mitral valve  30  opens allowing blood to be drawn into the left ventricle  32  for expulsion through the aortic valve  34  and on to the body extremities through the aorta  36 . When the heart  10  fails to continuously produce normal flow and pressures, a disease commonly referred to as heart failure occurs. 
     One cause of heart failure is failure or malfunction of one or more of the valves of the heart  10 . For example, the aortic valve  34  can malfunction for several reasons. For example, the aortic valve  34  may be abnormal from birth (e.g., bicuspid, calcification, congenital aortic valve disease), or it could become diseased with age (e.g., acquired aortic valve disease). In such situations, it can be desirable to replace the abnormal or diseased valve  34 . 
       FIG. 2  is a schematic illustration of the left ventricle  32 , which delivers blood to the aorta  36  through the aortic valve  34 . The aorta  36  comprises (i) the ascending aorta  38 , which arises from the left ventricle  32  of the heart  10 , (ii) the aortic arch  10 , which arches from the ascending aorta  38  and (iii) the descending aorta  42  which descends from the aortic arch  40  towards the abdominal aorta (not shown). Also shown are the principal branches of the aorta  14 , which include the innomate artery  44  that immediately divides into the right carotid artery (not shown) and the right subclavian artery (not shown), the left carotid  46  and the subclavian artery  48 . 
     Inflatable Prosthetic Aortic Valve Implant 
     With continued reference to  FIG. 2A , a cardiovascular prosthetic implant  800  in accordance with an embodiment of the present invention is shown spanning the native abnormal or diseased aortic valve  34 . The implant  800  and various modified embodiments thereof will be described in detail below. As will be explained in more detail below, the implant  800  is preferably delivered minimally invasively using an intravascular delivery catheter  900  or trans apical approach with a trocar. 
     In the description below, the present invention will be described primarily in the context of replacing or repairing an abnormal or diseased aortic valve  34 . However, various features and aspects of methods and structures disclosed herein are applicable to replacing or repairing the mitral  30 , pulmonary  22  and/or tricuspid  20  valves of the heart  10  as those of skill in the art will appreciate in light of the disclosure herein. In addition, those of skill in the art will also recognize that various features and aspects of the methods and structures disclosed herein can be used in other parts of the body that include valves or can benefit from the addition of a valve, such as, for example, the esophagus, stomach, ureter and/or vesice, biliary ducts, the lymphatic system and in the intestines. 
     In addition, various components of the implant and its delivery system will be described with reference to coordinate system comprising “distal” and “proximal” directions. In this application, distal and proximal directions refer to the deployment system  900 , which is used to deliver the implant  800  and advanced through the aorta  36  in a direction opposite to the normal direction of blood through the aorta  36 . Thus, in general, distal means closer to the heart while proximal means further from the heart with respect to the circulatory system. 
     In some embodiments, the implant  800  may be a prosthetic aortic valve implant. With reference to  FIG. 2B  in the illustrated embodiment, the implant  800  has a shape that can be viewed as a tubular member or hyperboloid shape where a waist  805  excludes the native valve  34  or vessel and proximally the proximal end  803  forms a hoop or ring to seal blood flow from re-entering the left ventricle  32 . Distally, the distal end  804  also forms a hoop or ring to seal blood from forward flow through the outflow track. Between the two ends  803  and  804 , the valve  104  is mounted to the cuff or body  802  such that when inflated the implant  800  excludes the native valve  34  or extends over the former location of the native valve  34  and replaces its function. The distal end  804  should have an appropriate size and shape so that it does not interfere with the proper function of the mitral valve, but still secures the valve adequately. For example, there may be a notch, recess or cut out in the distal end  804  of the device to prevent mitral valve interference. The proximal end  803  is designed to sit in the aortic root. It is preferably shaped in such a way that it maintains good apposition with the wall of the aortic root. This prevents the device from migrating back into the ventricle  32 . In some embodiments, the implant  800  is configured such that it does not extend so high that it interferes with the coronary arteries. 
     Any number of additional inflatable rings or struts may be disposed between the proximal end  803  and distal end  804 . The distal end  804  of the implant  800  is preferably positioned within the left ventricle  34  and can utilize the aortic root for axial stabilization as it may have a larger diameter than the aortic lumen. This may lessen the need for hooks, barbs or an interference fit to the vessel wall. Since the implant  800  may be placed without the aid of a dilatation balloon for radial expansion, the aortic valve  34  and vessel may not have any duration of obstruction and would provide the patient with more comfort and the physician more time to properly place the device accurately. Since the implant  800  is not utilizing a support member with a single placement option as a plastically deformable or shaped memory metal stent does, the implant  800  may be movable and or removable if desired. This could be performed multiple times until the implant  800  is permanently disconnected from the delivery catheter  900  as will be explained in more detail below. In addition, the implant  800  can include features, which allow the implant  800  to be tested for proper function, sealing and sizing, before the catheter  900  is disconnected. 
     With reference to  FIG. 3A , the implant  800  of the illustrated embodiment generally comprises an inflatable cuff or body  802 , which is configured to support a valve  104  (see  FIG. 2A ) that is coupled to the cuff  802 . In some embodiments, the valve  104  is a tissue valve. In some embodiments, the tissue valve has a thickness equal to or greater than about 0.011 inches. In another embodiment, the tissue valve has a thickness equal to or greater than about 0.018 inches. As will be explained in more detail below, the valve  104  is configured to move in response to the hemodynamic movement of the blood pumped by the heart  10  between an “open” configuration where blood can throw the implant  800  in a first direction (labeled A in  FIG. 2B ) and a “closed” configuration whereby blood is prevented from back flowing through the valve  104  in a second direction B (labeled B in  FIG. 2B ). 
     In the illustrated embodiment, the cuff  802  comprises a thin flexible tubular material such as a flexible fabric or thin membrane with little dimensional integrity. As will be explained in more detail below, the cuff  802  can be changed preferably, in situ, to a support structure to which other components (e.g., the valve  104 ) of the implant  800  can be secured and where tissue ingrowth can occur. Uninflated, the cuff  802  is preferably incapable of providing support. In one embodiment, the cuff  802  comprises Dacron, PTFE, ePTFE, TFE or polyester fabric as seen in conventional devices such as surgical stented or stent less valves and annuloplasty rings. The fabric thickness may range from about 0.002 inches to about 0.020 inches depending upon material selection and weave. Weave density may also be adjusted from a very tight weave to prevent blood from penetrating through the fabric to a looser weave to allow tissue to grow and surround the fabric completely. In preferred embodiments, the fabric may have a linear mass density about 20 denier or lower. 
     With reference to  FIGS. 3B-3D , in the illustrated embodiment, the implant  800  includes an inflatable structure  813  that is formed by one or more inflation channels  808 . The inflatable channels  808  are formed by a pair of distinct balloon rings or toroids ( 807   a  and  807   b ) and struts  806 . In the illustrated embodiment, the implant  800  comprises a proximal toroid  807   a  at the proximal end  803  of the cuff  802  and a distal toroid  807   b  at the distal end  804  of the cuff  802 . The toroids  807  can be secured to the cuff  802  in any of a variety of manners. With reference to  FIGS. 3C and 3D , in the illustrated embodiment, the toroids  807  are secured within folds  801  formed at the proximal end  803  and the distal end  804  of the cuff  802 . The folds  801 , in turn, are secured by sutures or stitches  812 . When inflated, the implant  800  is supported in part by series of struts  806  surrounding the cuff  802 . In some embodiments, the struts  806  are configured so that the portions on the cuff run substantially perpendicular to the toroids. In some embodiments, the struts are sewn onto the cuff  802  or are enclosed in lumens made from the cuff material and swan onto the cuff  802 . The toroids  807  and the struts  806  together form one or more inflatable channels  808  that can be inflated by air, liquid or inflation media. 
     With reference to  FIG. 3B , the inflation channels are configured so that the cross-sectional profile of the implant  800  is reduced when it is compressed or in the retracted state. The inflation channels  808  are arranged in a step-function pattern. The inflation channels  808  have three connection ports  809  for coupling to the delivery catheter  900  via position and fill lumen tubing (PFL) tubing  916  (see  FIGS. 5A-5C ). In some embodiments, at least two of the connection ports  809  also function as inflation ports, and inflation media, air or liquid can be introduced into the inflation channel  808  through these ports. The PFL tubing  916  can be connected to the connection ports  809  via suitable connection mechanisms. In one embodiment, the connection between the PFL tubing  916  and the connection port  809  is a screw connection. In some embodiments, an inflation valve  810  is present in the connection port  809  and can stop the inflation media, air or liquid from escaping the inflation channels  808  after the PFL tubing is disconnected. In some embodiments, the distal toroid  807   b  and the proximal toroid  807   a  may be inflated independently. In some embodiments, the distal toroid  807   b  can be inflated separately from the struts  806  and the proximal toroid  807   a . The separate inflation is useful during the positioning of the implant at the implantation site. With reference to  FIGS. 3C and 3D , in some embodiments, the portion of struts  806  that runs parallel to the toroids  807  is encapsulated within the folds  801  of the implant  800 . This may also aid in reducing the cross-sectional profile when the implant is compressed or folded. 
     As mentioned above, the inflatable rings or toroids  807  and struts  806  form the inflatable structure  813 , which, in turn, defines the inflation channels  808 . The inflation channels  808  receive inflation media to generally inflate the inflatable structure  813 . When inflated, the inflatable rings  807  and struts  806  can provide structural support to the inflatable implant  800  and/or help to secure the implant  800  thin the heart  10 . Uninflated, the implant  800  is a generally thin, flexible shapeless assembly that is preferably uncapable of support and is advantageously able to take a small, reduced profile form in which it can be percutaneously inserted into the body. As will be explained in more detail below, in modified embodiments, the inflatable structure  813  may comprise any of a variety of configurations of inflation channels  808  that can be formed from other inflatable members in addition to or in the alternative to the inflatable rings  807  and struts  806  shown in  FIGS. 3A and 3B . In one embodiment, the valve has an expanded diameter that is greater than or equal to 22 millimeters and a maximum compressed diameter that is less than or equal to 6 millimeters (18 F). 
     With particular reference to  FIG. 3B , in the illustrated embodiment, the distal ring  807   b  and struts  806  are joined such that the inflation channel  808  of the distal ring  807   b  is in fluid communication with the inflation channel  808  of some of the struts  806 . The inflation channel  808  of the proximal ring  807   a  is also in communication with the inflation channels  808  of the proximal ring  807   a  and a few of the struts  806 . In this manner, the inflation channels of the (i) proximal ring  807   a  and a few struts  806  can be inflated independently from the (ii) distal ring  807   b  and some struts. In some embodiments, the inflation channel of the proximal ring  807   a  is in communication with the inflation channel of the struts  806 , while the inflation channel of the distal ring  807   b  is not in communication with the inflation channel of the struts. As will be explained in more detail below, the two groups of inflation channels  808  are preferably connected to independent PFL tubing  916  to facilitate the independent inflation. It should be appreciated that in modified embodiments the inflatable structure can include less (i.e., one common inflation channel) or more independent inflation channels. For example, in one embodiment, the inflation channels of the proximal ring  807   a , struts  806  and distal ring  807   b  can all be in fluid communication with each other such that they can be inflated from a single inflation device. In another embodiment, the inflation channels of the proximal ring  807   a , struts  806  and distal ring  807   b  can all be separated and therefore utilize three inflation devices. 
     With reference to  FIG. 3B , in the illustrated embodiment, each of the proximal ring  807   a  and the distal ring  807   b  has a cross-sectional diameter of about 0.090 inches. The struts have a cross-sectional diameter of about 0.060 inches. In some embodiments, within the inflation channels  808  are also housed valve systems that allow for pressurization without leakage or passage of fluid in a single direction. In the illustrated embodiment shown in  FIG. 3B , two end valves or inflation valves  810  reside at each end section of the inflation channels  808  adjacent to the connection ports  809 . These end valves  810  are utilized to fill and exchange fluids such as saline, contrast agent and inflation media. The length of this inflation channel  808  may vary depending upon the size of the implant  800  and the complexity of the geometry. The inflation channel material may be blown using heat and pressure from materials such as nylon, polyethylene, Pebax, polypropylene or other common materials that will maintain pressurization. The fluids that are introduced are used to create the support structure, where without them, the implant  800  is an undefined fabric and tissue assembly. In one embodiment the inflation channels  808  are first filled with saline and contrast agent for radiopaque visualization under fluoroscopy. This can make positioning the implant  800  at the implantation site easier. This fluid is introduced from the proximal end of the catheter  900  with the aid of an inflation device such as an endoflator or other means to pressurize fluid in a controlled manner. This fluid is transferred from the proximal end of the catheter  900  through the PFL tubes  916  which are connected to the implant  800  at the end of each inflation channel  808  at the connection port  809 . 
     With reference to  FIG. 3B , in the illustrated embodiment, the inflation channel  808  can have an end valve  810  (i.e., inflation valve) at each end whereby they can be separated from the PFL tubes  916  thus disconnecting the catheter from the implant. This connection can be a screw or threaded connection, a colleting system, an interference fit or other means of reliable securement between the two components (i.e., the end valve  810  and the PFL tubes  916 ). In between the ends of the inflation channel  808  is an additional directional valve  811  to allow fluid to pass in a single direction. This allows for the filling of each end of the inflation channel  808  and displacement of fluid in a single direction. Once the implant  808  is placed at the desired position while inflated with saline and contrast agent, this fluid can be displaced by an inflation media that can solidify or harden. As the inflation media is introduced from the proximal end of the catheter  900 , the fluid containing saline and contrast agent is pushed out from one end of the inflation channel  808 . Once the inflation media completely displaces the first fluid, the PFL tubes are then disconnected from the implant  800  while the implant  800  remains inflated and pressurized. The pressure is maintained in the implant  800  by the integral valve (i.e., end valve  810 ) at each end of the inflation channel  808 . In the illustrated embodiment, this end valve  810  has a ball  303  and seat to allow for fluid to pass when connected and seal when disconnected. In some case the implant  800  has three or more connection ports  809 , but only two have inflation valves  810  attached. The connection port without the end valve  810  may use the same attachment means such as a screw or threaded element. Since this connection port is not used for communication with the support structure  813  and its filling, no inflation valve  810  is necessary. In other embodiments, all three connection ports  809  may have inflation valves  810  for introducing fluids or inflation media. 
     With reference to  FIG. 4 , the end valve system  810  comprises a tubular section  312  with a soft seal  304  and spherical ball  303  to create a sealing mechanism  313 . The tubular section  312  in one embodiment is about 0.5 cm to about 2 cm in length and has an outer diameter of about 0.010 inches to about 0.090 inches with a wall thickness of about 0.005 inches to about 0.040 inches. The material may include a host of polymers such as nylon, polyethylene, Pebax, polypropylene or other common materials such as stainless steel, Nitinol or other metallic materials used in medical devices. The soft seal material may be introduced as a liquid silicone or other material where a curing occurs thus allowing for a through hole to be constructed by coring or blanking a central lumen through the seal material. The soft seal  304  is adhered to the inner diameter of the wall of the tubular member  312  with a through hole for fluid flow. The spherical ball  303  is allowed to move within the inner diameter of the tubular member  312  where it seats at one end sealing pressure within the inflation channels and is moved the other direction with the introduction of the PFL tube  916  but not allowed to migrate too far as a stop ring or ball stopper  305  retains the spherical ball  303  from moving into the inflation channel  808 . As the PFL tube  916  is screwed into the connection port  809 , the spherical ball  303  is moved into an open position to allow for fluid communication between the inflation channel  808  and the PFL tube  916 . When disconnected, the ball  303  is allowed to move against the soft seal  304  and halt any fluid communication external to the inflation channel  808  leaving the implant  800  pressurized. Additional embodiments may utilize a spring mechanism to return the ball to a sealed position and other shapes of sealing devices may be used rather than a spherical ball. A duck-bill style sealing mechanism or flap valve would additionally suffice to halt fluid leakage and provide a closed system to the implant. Additional end valve systems have been described in U.S. Patent Publication No. 2009/0088836 to Bishop et al., which is thereby incorporated by reference herein. 
     The implant  800  allows the physician to deliver a prosthetic valve via catheterization in a lower profile and a safer manner than currently available. When the implant  800  is delivered to the site via a delivery catheter  900 , the implant  800  is a thin, generally shapeless assembly in need of structure and definition. At the implantation site, the inflation media (e.g., a fluid or gas) may be added via PFL tubes of the delivery catheter  900  to the inflation channels  808  providing structure and definition to the implant  800 . The inflation media therefore comprises part of the support structure for implant  800  after it is inflated. The inflation media that is inserted into the inflation channels  808  can be pressurized and/or can solidify in situ to provide structure to the implant  800 . Additional details and embodiments of the implant  800 , can be found in U.S. Pat. No. 5,554,185 to Block and U.S. Patent Publication No. 2006/0088836 to Bishop et al., the disclosures of which are expressly incorporated by reference in their entirety herein. 
     The cuff  802  may be made from many different materials such as Dacron, TFE, PTFE, ePTFE, woven metal fabrics, braided structures, or other generally accepted implantable materials. These materials may also be cast, extruded, or seamed together using heat, direct or indirect, sintering techniques, laser energy sources, ultrasound techniques, molding or thermoforming technologies. Since the inflation channels  808  generally surrounds the cuff  802 , and the inflation channels  808  can be formed by separate members (e.g., balloons and struts), the attachment or encapsulation of these inflation channels  808  can be in intimate contact with the cuff material. In some embodiments, the inflation channels  808  are encapsulated in the folds  801  or lumens made from the cuff material sewn to the cuff  802 . These inflation channels  808  can also be formed by sealing the cuff material to create an integral lumen from the cuff  802  itself. For example, by adding a material such as a silicone layer to a porous material such as Dacron, the fabric can resist fluid penetration or hold pressures if sealed. Materials may also be added to the sheet or cylinder material to create a fluid-tight barrier. 
     Various shapes of the cuff  802  may be manufactured to best fit anatomical variations from person to person. As described above, these may include a simple cylinder, a hyperboloid, a device with a larger diameter in its mid portion and a smaller diameter at one or both ends, a funnel type configuration or other conforming shape to native anatomies. The shape of the implant  800  is preferably contoured to engage a feature of the native anatomy in such a way as to prevent the migration of the device in a proximal or distal direction. In one embodiment the feature that the device engages is the aortic root or aortic bulb  34  (see e.g.,  FIG. 2A ), or the sinuses of the coronary arteries. In another embodiment the feature that the device engages is the native valve annulus, the native valve or a portion of the native valve. In certain embodiments, the feature that the implant  800  engages to prevent migration has a diametral difference between 1% and 10%. In another embodiment, the feature that the implant  800  engages to prevent migration the diameter difference is between 5% and 40%. In certain embodiments the diameter difference is defined by the free shape of the implant  800 . In another embodiment the diameter difference prevents migration in only one direction. In another embodiment, the diameter difference prevents migration in two directions, for example proximal and distal or retrograde and antigrade. Similar to surgical valves, the implant  800  will vary in diameter ranging from about 14 mm to about 30 mm and have a height ranging from about 10 mm to about 30 mm in the portion of the implant  800  where the leaflets of the valve  104  are mounted. Portions of the implant  800  intended for placement in the aortic root may have larger diameters preferably ranging from about 20 mm to about 45 mm. In some embodiment, the implant  800  has an outside diameter greater than about 22 mm when fully inflated. 
     In certain embodiments, the cuffs, inflated structure can conform (at least partially) to the anatomy of the patient as the implant  800  is inflated. Such an arrangement may provide a better seal between the patient&#39;s anatomy and the implant  800 . 
     Different diameters of prosthetic valves will be needed to replace native valves of various sizes. For different locations in the anatomy, different lengths of prosthetic valves or anchoring devices will also be required. For example a valve designed to replace the native aortic valve needs to have a relatively short length because of the location of the coronary artery ostium (left and right arteries). A valve designed to replace or supplement a pulmonary valve could have significantly greater length because the anatomy of the pulmonary artery allows for additional length. Different anchoring mechanisms that may be useful for anchoring the implant  800  have been described in U.S. Patent Publication No. 2009/0088836 to Bishop et al. 
     In the embodiments described herein, the inflation channels  808  may be configured such that they are of round, oval, square, rectangular or parabolic shape in cross section. Round cross sections may vary from about 0.020-about 0.100 inches in diameter with wall thicknesses ranging from about 0.0005-about 0.010 inches. Oval cross sections may have an aspect ratio of two or three to one depending upon the desired cuff thickness and strength desired. In embodiments in which the inflation channels  808  are formed by balloons, these channels  808  can be constructed from conventional balloon materials such as nylon, polyethylene, PEEK, silicone or other generally accepted medical device material 
     In some embodiments, portions of the cuff or body  802  can be radio-opaque to aid in visualizing the position and orientation of the implant  800 . Markers made from platinum gold or tantalum or other appropriate materials may be used. These may be used to identify critical areas of the valve that must be positioned appropriately, for example the valve commissures may need to be positioned appropriately relative to the coronary arteries for an aortic valve. Additionally during the procedure it may be advantageous to catheterize the coronary arteries using radio-opaque tipped guide catheters so that the ostia can be visualized. Special catheters could be developed with increased radio-opacity or larger than standard perfusion holes. The catheters could also have a reduced diameter in their proximal section allowing them to be introduced with the valve deployment catheter. 
     As mentioned above, during delivery, the body  802  is limp and flexible providing a compact shape to fit inside a delivery sheath. The body  802  is therefore preferably made form a thin, flexible material that is biocompatible and may aid in tissue growth at the interface with the native tissue. A few examples of material may be Dacron, ePTFE, PTFE, TFE, woven material such as stainless steel, platinum, MP35N, polyester or other implantable metal or polymer. As mentioned above with reference to  FIG. 2A , the body  802  may have a tubular or hyperboloid shape to allow for the native valve to be excluded beneath the wall of the cuff  802 . Within this cuff  802  the inflation channels  808  can be connected to a catheter lumen for the delivery of an inflation media to define and add structure to the implant  800 . The valve  104 , which is configured such that a fluid, such as blood, may be allowed to flow in a single direction or limit flow in one or both directions, is positioned within the cuff  802 . The attachment method of the valve  104  to the cuff  802  can be by conventional sewing, gluing, welding, interference or other means generally accepted by industry. 
     In one embodiment, the cuff  802  would have a diameter of between about 15 mm and about 30 mm and a length of between about 6 mm and about 70 mm. The wall thickness would have an ideal range from about 0.01 mm to about 2 mm. As described above, the cuff  802  may gain longitudinal support in situ from members formed by inflation channels or formed by polymer or solid structural elements providing axial separation. The inner diameter of the cuff  802  may have a fixed dimension providing a constant size for valve attachment and a predictable valve open and closure function. Portions of the outer surface of the cuff  802  may optionally be compliant and allow the implant  800  to achieve interference fit with the native anatomy. 
     The implant  800  can have various overall shapes (e.g., an hourglass shape to hold the device in position around the valve annulus, or the device may have a different shape to hold the device in position in another portion of the native anatomy, such as the aortic root). Regardless of the overall shape of the implant  800 , the inflatable channels  808  can be located near the proximal and distal ends  803 ,  804  of the implant  800 , preferably forming a configuration that approximates a ring or toroid  807 . These channels may be connected by intermediate channels designed to serve any combination of three functions: (i) provide support to the tissue excluded by the implant  800 , (ii) provide axial and radial strength and stiffness to the  800 , and/or (iii) to provide support for the valve  104 . The specific design characteristics or orientation of the inflatable structure  813  can be optimized to better serve each function. For example if an inflatable channel  808  were designed to add axial strength to the relevant section of the device, the channels  808  would ideally be oriented in a substantially axial direction. 
     The cuff  802  and inflation channels  808  of the implant  800  can be manufactured in a variety of ways. In one embodiment the cuff  802  is manufactured from a fabric, similar to those fabrics typically used in endovascular grafts or for the cuffs of surgically implanted prosthetic heart valves. The fabric is preferably woven into a tubular shape for some portions of the cuff  802 . The fabric may also be woven into sheets. In one embodiment, the yarn used to manufacture the fabric is preferably a twisted yarn, but monofilament or braided yarns may also be used. The useful range of yarn diameters is from approximately 0.0005 of an inch in diameter to approximately 0.005 of an inch in diameter. Depending on how tight the weave is made. Preferably, the fabric is woven with between about 50 and about 500 yarns per inch. In one embodiment, a fabric tube is woven with a 18 mm diameter with 200 yarns per inch or picks per inch. Each yarn is made of 20 filaments of a PET material. The final thickness of this woven fabric tube is 0.005 inches for the single wall of the tube. Depending on the desired profile of the implant  800  and the desired permeability of the fabric to blood or other fluids different weaves may be used. Any biocompatible material may be used to make the yarn, some embodiments include nylon and PET. Other materials or other combinations of materials are possible, including Teflon, floropolymers, polyimide, metals such as stainless steel, titanium, Nitinol, other shape memory alloys, alloys comprised primarily of a combinations of cobalt, chromium, nickel, and molybdenum. Fibers may be added to the yarn to increases strength or radiopacity, or to deliver a pharmaceutical agent. The fabric tube may also be manufactured by a braiding process. 
     The fabric can be stitched, sutured, sealed, melted, glued or bonded together to form the desired shape of the implant  800 . The preferred method for attaching portions of the fabric together is stitching. The preferred embodiment uses a polypropylene monofilament suture material, with a diameter of approximately 0.005 of an inch. The suture material may range from about 0.001 to about 0.010 inches in diameter. Larger suture materials may be used at higher stress locations such as where the valve commissures attach to the cuff. The suture material may be of any acceptable implant grade material. Preferably a biocompatible suture material is used such as polypropylene. Nylon and polyethylene are also commonly used suture materials. Other materials or other combinations of materials are possible, including Teflon, fluoropolymers, polyimides, metals such as stainless steel, titanium, Kevlar, Nitinol, other shape memory alloys, alloys comprised primarily of a combinations of cobalt, chromium, nickel, and molybdenum such as MP35N. Preferably the sutures are a monofilament design. Multi strand braided or twisted suture materials also may be used. Many suture and stitching patterns are possible and have been described in various texts. The preferred stitching method is using some type of lock stitch, of a design such that if the suture breaks in a portion of its length the entire running length of the suture will resist unraveling. And the suture will still generally perform its function of holding the layers of fabric together. 
     In some embodiments, the implant  800  is not provided with separate balloons, instead the fabric of the cuff  802  itself can form the inflation channels  808 . For example, in one embodiment two fabric tubes of a diameter similar to the desired final diameter of the implant  800  are place coaxial to each other. The two fabric tubes are stitched, fused, glued or otherwise coupled together in a pattern of channels  808  that is suitable for creating the geometry of the inflatable structure  813 . In some embodiments, the fabric tubes are sewn together in a pattern so that the proximal and distal ends of the fabric tubes form an annular ring or toroid  807 . In some embodiments, the middle section of the implant  800  contains one or more inflation channels shaped in a step-function pattern. In some embodiments, the fabric tubes are sewn together at the middle section of the implant to form inflation channels  808  that are perpendicular to the toroids  807  at the end sections of the implant  800 . Methods for fabricating the implant  800  have been described in U.S. Patent Publication No. 2006/0088836 to Bishop et al. 
     In the illustrated embodiment of  FIGS. 3A and 3B , the struts  806  are arranged such that there is no radial overlap with the distal and proximal rings  807   a ,  807   b . That is, in the illustrated embodiment, the struts  808  do not increase the radial thickness of the inflation structure because there is no radial overlap between the distal and proximal rings and the channels so that the channels lie within the radial thickness envelop defined by the distal and proximal rings  807   a ,  807   b . In another embodiment, the struts  808  can be wider in the radial direction than the distal and proximal rings  807   a ,  807   b  such that the distal and proximal rings  807   a ,  807   b  lie within a radial thickness envelop defined by the struts  806 . 
     In one embodiment, the valve  800  can be delivered through a deployment catheter with an 18 F or smaller outer diameter and when fully inflated has an effective orifice area of at least about 1.0 square cm; and in another embodiment at least about 1.3 square cm and in another embodiment about 1.5 square cm. In one embodiment, the valve  800  has a minimum cross-sectional flow area of at least about 1.75 square cm. 
     Leaflet Subassembly 
     With reference back to the embodiments of  FIG. 2A , the valve  104  preferably is a tissue-type heart valve that includes a dimensionally stable, pre-aligned tissue leaflet subassembly. Pursuant to this construction, an exemplary tissue valve  104  includes a plurality of tissue leaflets that are templated and attached together at their tips to form a dimensionally stable and dimensionally consistent coapting leaflet subassembly. Then, in what can be a single process, each of the leaflets of the subassembly is aligned with and individually sewn to the cuff  802 , from the tip of one commissure uniformly, around the leaflet cusp perimeter, to the tip of an adjacent commissure. As a result, the sewed sutures act like similarly aligned staples, all of which equally take the loading force acting along the entire cusp of each of the pre-aligned, coapting leaflets. Once inflated, the cuff  802  supports the commissures with the inflation media and its respective pressure which will solidify and create a system similar to a stent structure. The resulting implant  800  thereby formed can reduce stress and potential fatigue at the leaflet suture interface by distributing stress evenly over the entire leaflet cusp from commissure to commissure. In some embodiments, the tissue valve is coupled to the inflatable cuff  802  by attaching to the fabric of the cuff only. 
     In one embodiment, the tissue leaflets are not coupled to each other but are instead individually attached to the cuff  802 . 
     A number of additional advantages result from the use of the implant  800  and the cuff  802  construction utilized therein. For example, for each key area of the cuff  802 , the flexibility can be optimized or customized. If desired, the coapting tissue leaflet commissures can be made more or less flexible to allow for more or less deflection to relieve stresses on the tissue at closing or to fine tune the operation of the valve. Similarly, the base radial stiffness of the overall implant structure can be increased or decreased by pressure or inflation media to preserve the roundness and shape of the implant  800 . 
     Attachment of the valve  104  to the cuff  802  can be completed in any number of conventional methods including sewing, ring or sleeve attachments, gluing, welding, interference fits, bonding through mechanical means such as pinching between members. An example of these methods are described in Published Applications from Huynh et al (Ser. No. 06/102,944) or Lafrance et al (2003/0027332) or U.S. Pat. No. 6,409,759 to Peredo, which are hereby incorporated by reference herein. These methods are generally know and accepted in the valve device industry. The valve, whether it is tissue, engineered tissue, mechanical or polymer, may be attached before packaging or in the hospital just before implantation. Some tissue valves are native valves such as pig, horse, cow or native human valves. Most of which are suspended in a fixing solution such as Glutaraldehyde. 
     In some embodiments, heart valve prostheses can be constructed with flexible tissue leaflets or polymer leaflets. Prosthetic tissue heart valves can be derived from, for example, porcine heart valves or manufactured from other biological material, such as bovine or equine pericardium. Biological materials in prosthetic heart valves generally have profile and surface characteristics that provide laminar, nonturbulent blood flow. Therefore, intravascular clotting is less likely to occur than with mechanical heart valve prostheses. 
     Natural tissue valves can be derived from an animal species, typically mammalian, such as human, bovine, porcine canine, seal or kangaroo. These tissues can be obtained from, for example, heart valves, aortic roots, aortic walls, aortic leaflets, pericardial tissue such as pericardial patches, bypass grafts, blood vessels, human umbilical tissue and the like. These natural tissues are typically soft tissues, and generally include collagen containing material. The tissue can be living tissue, decellularized tissue or recellularized tissue. Tissue can be fixed by crosslinking. Fixation provides mechanical stabilization, for example by preventing enzymatic degradation of the tissue. Glutaraldehyde or formaldehyde is typically used for fixation, but other fixatives can be used, such as other difunctional aldehydes, epoxides, genipin and derivatives thereof. Tissue can be used in either crosslinked or uncrosslinked form, depending on the type of tissue, use and other factors. Generally, if xenograft tissue is used, the tissue is crosslinked and/or decellularized. Additional description of tissue valves can be found in U.S. Patent Publication No. 2009/008836 to Bishop et al. 
     Inflation Media 
     The inflatable structure  813  can be inflated using any of a variety of inflation media, depending upon the desired performance. In general, the inflation media can include a liquid such water or an aqueous based solution, a gas such as CO 2 , or a hardenable media which may be introduced into the inflation channels  808  at a first, relatively low viscosity and converted to a second, relatively high viscosity. Viscosity enhancement may be accomplished through any of a variety of known UV initiated or catalyst initiated polymerization reactions, or other chemical systems known in the art. The end point of the viscosity enhancing process may result in a hardness anywhere from a gel to a rigid structure, depending upon the desired performance and durability. 
     Useful inflation media generally include those formed by the mixing of multiple components and that have a cure time ranging from a tens of minutes to about one hour, preferably from about twenty minutes to about one hour. Such a material may be biocompatible, exhibit long-term stability (preferably on the order of at least ten years in vivo), pose as little an embolic risk as possible, and exhibit adequate mechanical properties, both pre and post-cure, suitable for service in the cuff of the present invention in vivo. For instance, such a material should have a relatively low viscosity before solidification or curing to facilitate the cuff and channel fill process. A desirable post-cure elastic modulus of such an inflation medium is from about 50 to about 400 psi—balancing the need for the filled body to form an adequate seal in vivo while maintaining clinically relevant kink resistance of the cuff. The inflation media ideally should be radiopaque, both acute and chronic, although this is not absolutely necessary. 
     One preferred family of hardenable inflation media are two part epoxies. The first part is an epoxy resin blend comprising a first aromatic diepoxy compound and a second aliphatic diepoxy compound. The first aromatic diepoxy compound provides good mechanical and chemical stability in an aqueous environment while being soluble in aqueous solution when combined with suitable aliphatic epoxies. In some embodiments, the first aromatic diepoxy compound comprises at least one N,N-diglycidylaniline group or segment. In some embodiments, the first aromatic diepoxy compound are optionally substituted N,N-diglycidylaniline. The substitutent may be glycidyloxy or N,N-diglycidylanilinyl-methyl. Non-limiting examples of the first aromatic diepoxy compound are N,N-diglycidylaniline, N,N-diclycidyl-4-glycidyloxyaniline (DGO) and 4,4′-methylene-bis(N,N-diglycidylaniline) (MBD), etc. 
     The second aliphatic diepoxy compound provides low viscosity and good solubility in an aqueous solution. In some embodiments, the second aliphatic diepoxy compound may be 1,3-butadiene diepoxide, glycidyl ether or C 1-5  alkane diols of glycidyl ether. Non-limiting examples of the second aliphatic diepoxy compounds are 1,3-butadiene diepoxide, butanediol diglycidyl ether (BDGE), 1,2-ethanediol diglycidyl ether, glycidyl ether, etc. 
     In some embodiments, additional third compound may be added to the first part epoxy resin blend for improving mechanical properties and chemical resistance. In some embodiments, the additional third compound may be an aromatic epoxy other than the one containing N,N-diglycidylanaline. However, the solubility of the epoxy resin blend can also decrease and the viscosity can increase as the concentration of the additional aromatic epoxies increases. The preferred third compound may be tris(4-hydroxyphenyl)methane triglycidyl ether (THTGE), bisphenol A diglycidyl ether (BADGE), bisphenol F diglycidyl ether (BFDGE), or resorcinol diglycidyl ether (RDGE). 
     In some embodiments, the additional third compound may be a cycloaliphatic epoxy compound, preferably more soluble than the first aromatic diepoxy compound. It can increase the mechanical properties and chemical resistance to a lesser extent than the aromatic epoxy described above, but it will not decrease the solubility as much. Non-limiting examples of such cycloaliphatic epoxy are 1,4-cyclohexanedimethanol diclycidyl ether and cyclohexene oxide diglycidyl 1,2-cyclohexanedicarboxylate. Similarly, in some embodiments, aliphatic epoxy with 3 or more glycidyl ether groups, such as polyglycidyl ether, may be added as the additional third compound for the same reason. Polyglycidyl ether may increase cross linking and thus enhance the mechanical properties. 
     In general, the solubility of the epoxy resin blend decreases and the viscosity increases as the concentration of the first aromatic diepoxy compound increases. In addition, the mechanical properties and chemical resistance may be reduced as the concentration of the aliphatic diepoxy compound goes up in the epoxy resin blend. By adjusting the ratio of the first aromatic dipoxy compound and the second aliphatic diepoxy compound, a person skilled in the art can control the desired properties of the epoxy resin blend and the hardened media. Adding the third compound in some embodiments may allow further tailoring of the epoxy resin properties. 
     The second part of the hardenable inflation media comprises a hardener comprising at least one cycloaliphatic amine. It provides good combination of reactivity, mechanical properties and chemical resistance. The cycloaliphatic amine may include, but not limited to, isophorone diamine (IPDA), 1,3-bisaminocyclohexame (1,3-BAC), diamino cyclohexane (DACH), n-aminoethylpiperazine (AEP) or n-aminopropylpiperazine (APP). 
     In some embodiments, an aliphatic amine may be added into the second part to increase reaction rate, but may decrease mechanical properties and chemical resistance. The preferred aliphatic amine has the structural formula (I): 
     
       
         
         
             
             
         
       
     
     wherein each R is independently selected from branched or linear chains of C 2-5  alkyl, preferably C 2  alkyl. The term “alkyl” as used herein refers to a radical of a fully saturated hydrocarbon, including, but not limited to, methyl, ethyl, n-propyl, isopropyl (or i-propyl), n-butyl, isobutyl, tert-butyl (or t-butyl), n-hexyl, and the like. For example, the term “alkyl” as used herein includes radicals of fully saturated hydrocarbons defined by the following general formula C n H 2n+2 . In some embodiments, the aliphatic amine may include, but not limited to, tetraehtylenepentamine (TEPA), diethylene triamine and triethylene tetraamine. In some embodiments, the hardener may further comprise at least one radio-opaque compound, such as iodo benzoic acids. 
     Additional details of hardenable inflation media are described in co-pending application titled “Inflation Media Formulation,” hereby incorporated herein by reference. Other suitable inflation media are also described in U.S. patent application Ser. No. 09/496,231 to Hubbell et al., filed Feb. 1, 2000, entitled “Biomaterials Formed by Nucleophilic Addition Reaction to Conjugated Unsaturated Groups” and U.S. Pat. No. 6,958,212 to Hubbell et al. The entireties of each of these patents are hereby incorporated herein by reference. 
     Below is Listed One Particular Two-Component Medium. This Medium Comprises: First Part—Epoxy Resin Blend 
     (1) N,N-Diglycidyl-4-glycidyloxyaniline (DGO), present in a proportion ranging from about 10 to about 70 weight percent; specifically in a proportion of about 50 weight percent, 
     (2) Butanediol diglycidyl ether (BDGE) present in a proportion ranging from about 30 to about 75 weight percent; specifically in a proportion of about 50 weight percent, and optionally 
     (3) 1,4-Cyclohexanedimethanol diglycidyl ether, present in a proportion ranging from about 0 to about 50 weight percent. 
     Second Part—Amine Hardener 
     (1) Isophorone diamine (IPDA), present in a proportion ranging from about 75 to about 100 weight percent, and optionally 
     (2) Diethylene triamine (DETA), present in a proportion ranging from about 0 to about 25 weight percent. 
     The mixed uncured inflation media preferably has a viscosity less than 2000 cps. In one embodiment the epoxy based inflation media has a viscosity of 100-200 cps. In another embodiment the inflation media has a viscosity less than 1000 cps. In some embodiments, the epoxy mixture has an initial viscosity of less than about 50 cps, or less than about 30 cps after mixing. In some embodiments, the average viscosity during the first 10 minutes following mixing the two components of the inflation media is about 50 cps to about 60 cps. The low viscosity ensures that the inflation media can be delivered through the inflation lumen of a deployment catheter with small diameter, such as an 18 French catheter 
     In some embodiments, the balloon or inflation channel may be connected to the catheter on both ends. This allows the balloon to be pre-inflated with a non-solidifying material such as a gas or liquid. If a gas is chosen, CO 2  or helium are the likely choices; these gasses are used to inflate intraortic balloon pumps. Preferably the pre-inflation media is radio-opaque so that the balloon position can be determined by angiography. Contrast media typically used in interventional cardiology could be used to add sufficient radio-opacity to most liquid pre-inflation media. When it is desired to make the implant permanent and exchange the pre-inflation media for the permanent inflation media, the permanent inflation media is injected into the inflation channel through a first catheter connection. In some embodiments, the permanent inflation media is capable of solidifying into a semi-solid, gel or solid state. As the permanent inflation media is introduced into the inflatable structure, the pre-inflation media is expelled out from a second catheter connection. The catheter connections are positioned in such a way that substantially all of the pre-inflation media is expelled as the permanent inflation media is introduced. In one embodiment an intermediate inflation media is used to prevent entrapment of pre-inflation media in the permanent inflation media. In one embodiment the intermediate inflation media is a gas and the pre-inflation media is a liquid. In another embodiment the intermediate inflation media or pre-inflation media functions as a primer to aid the permanent inflation media to bond to the inner surface of the inflation channel. In another embodiment the pre-inflation media or the intermediate inflation media serves as a release agent to prevent the permanent inflation media from bonding to the inner surface of the inflation channel. 
     The permanent inflation media may have a different radiopacity than the preinflation media. A device that is excessively radiopaque tends to obscure other nearby features under angiography. During the preinflation step it may be desirable to visualize the inflation channel clearly, so a very radiopaque inflation media may be chosen. After the device is inflated with the permanent inflation media a less radiopaque inflation media may be preferred. The feature of lesser radiopacity is beneficial for visualization of proper valve function as contrast media is injected into the ventricle or the aorta. 
     Another embodiment of the inflation media is disclosed in co-pending application filed on the same day as this application under Attorney Docket: DFMED.034A, entitled INFLATION MEDIA FOR IMPLANTS, and U.S. Provisional Patent Application No. 61/346,419 filed May 19, 2011, the entirety of these applications are hereby incorporated by reference herein. 
     Low Crossing Profile Delivery System 
       FIGS. 5A-5B  illustrate an exemplary embodiment of a low crossing profile delivery catheter  900  that can be used to deliver the implant  800 . In general, the delivery system comprises a delivery catheter  900 , and the delivery catheter  900  comprises an elongate, flexible catheter body having a proximal end and a distal end. In some embodiments, the catheter body has an outer diameter of about 18 French or less particularly at the distal portion of the catheter body (i.e. the deployment portion). In some embodiments, the delivery catheter also comprises a cardiovascular prosthetic implant  800  at the distal end of the catheter body. As described herein, certain features of the implant  800  and delivery catheter  900  are particularly advantageous for facilitating delivering of cardiovascular prosthetic implant  800  an within a catheter body having outer diameter of about 18 French or less while still maintaining a tissue valve thickness equal to or greater than about 0.011 inches and/or having an effective orifice area equal to or greater than about 1 cm squared, or in another embodiment, 1.3 cm squared or in another embodiment 1.5 cm squared. In such embodiments, the implant  800  may also have an expanded maximum diameter that is greater than or equal to about 22 mm. In some embodiments, at least one link exists between the catheter body and the implant  800 . In some embodiments, the at least one link is the PFL tubing. In one embodiment, the delivery system is compatible with 0.035″ or 0.038″ guidewire. 
     In general, the delivery catheter  900  can be constructed with extruded tubing using well known techniques in the industry. In some embodiments, the catheter  900  can incorporates braided or coiled wires and or ribbons into the tubing for providing stiffness and rotational torqueability. Stiffening wires may number between 1 and 64. In some embodiments, a braided configuration is used that comprises between 8 and 32 wires or ribbon. If wires are used in other embodiments, the diameter can range from about 0.0005 inches to about 0.0070 inches. If a ribbon is used, the thickness is preferably less than the width, and ribbon thicknesses may range from about 0.0005 inches to about 0.0070 inches while the widths may range from about 0.0010 inches to about 0.0100 inches. In another embodiment, a coil is used as a stiffening member. The coil can comprise between 1 and 8 wires or ribbons that are wrapped around the circumference of the tube and embedded into the tube. The wires may be wound so that they are parallel to one another and in the curved plane of the surface of the tube, or multiple wires may be wrapped in opposing directions in separate layers. The dimensions of the wires or ribbons used for a coil can be similar to the dimensions used for a braid. 
     With reference to  FIGS. 5A and 5B , the catheter  900  comprises an outer tubular member  801  having a proximal end  902  and a distal end  903 , and an inner tubular member  904  also having a proximal end  905  and a distal end  906 . The inner tubular member  904  extends generally through the outer tubular member  901 , such that the proximal and distal ends  902 ,  903  of the inner tubular member  904  extend generally past the proximal end  902  and distal end  903  of the outer tubular member  901 . The distal end  903  of the outer tubular member  901  comprises a sheath jacket  912 . In some embodiments, the sheath jacket  912  may comprise KYNAR tubing. The sheath jacket  912  can house the implant  800  in a retracted state for delivery to the implantation site. In some embodiments, the sheath jacket  912  is capable of transmitting at least a portion of light in the visible spectrum. This allows the orientation of the implant  800  to be visualized within the catheter  900 . In some embodiments, an outer sheath marking band  913  may be located at the distal end  903  of the outer tubular member  901 . The proximal end  905  of the inner tubular member  904  is connected to a handle  907  for grasping and moving the inner tubular member  904  with respect to the outer tubular member  901 . The proximal end  902  of the outer tubular member  901  is connected to an outer sheath handle  908  for grasping and holding the outer tubular member  901  stationary with respect to the inner tubular member  904 . A hemostasis seal  909  is preferably provided between the inner and outer tubular members  901 ,  904 , and the hemostasis seal  909  is disposed in outer sheath handle  908 . In some embodiments, the outer sheath handle  908  comprises a sideport valve  921 , and the fluid can be passed into the outer tubular member through it. 
     In general, the inner tubular member  904  comprises a multilumen hypotube (see  FIG. 6 ). In some embodiments, a neck section  910  is located at the proximal end  905  of the inner tubular member  904 . The neck section  910  may be made from stainless steel, Nitinol or another suitable material which can serve to provide additional strength for moving the inner tubular member  904  within the outer tubular member  901 . In some embodiments, a mulilumen marker band  911  is present at the distal end  906  of the inner tubular member  904 . The multilumen hypotube has a wall thickness between about 0.004 in and about 0.006 in. In a preferred embodiment, the wall thickness is about 0.0055 in, which provides sufficient column strength and increases the bending load required to kink the hypotube. With reference to  FIG. 6 , the inner tubular member  904  (i.e., multilumen hypotube) comprises at least four lumens. One of the lumens accommodates the guidewire tubing  914 , and each of the other lumens accommodates a positioning-and-fill lumen (PFL) tubing  916 . The guidewire tubing  914  is configured to receive a guidewire. The PFL tubing  916  is configured to function both as a control wire for positioning the implant  800  at the implantation cite, and as an inflation tube for delivering a liquid, gas or inflation media to the implant  800 . In particular, the tubing  916  can allow angular adjustment of the implant  800 . That is, the plane of the valve (defined generally perpendicular to the longitudinal axis of the implant  800 ) can be adjusted with the tubing  916 . 
     With reference to  FIGS. 5A and 5B , in general, the guidewire tubing  914  is longer than and extends throughout the length of the delivery catheter  900 . The proximal end of the guidewire tubing  914  passes through the inner sheath handle  907  for operator&#39;s control; the distal end of the guidewire tubing  914  extends past the distal end  903  of the outer tubular member  901 , and is coupled to a guidewire tip  915 . The guidewire tip  915  can close the distal end  903  of the outer tubular member  901  (or the receptacle) and protect the retracted implant  800 , for example, during the advancement of the delivery catheter. The guidewire tip  915  can be distanced from the outer tubular member  901  by proximally retracting the outer tubular member  901  while holding the guidewire tubing  914  stationary. Alternatively, the guidewire tubing  914  can be advanced while holding the outer tubular member  901  stationary. The guidewire tubing  914  may have an inner diameter of about 0.035 inches to about 0.042 inches, so the catheter system is compatible with common 0.035″ or 0.038″ guidewires. In some embodiments, the guidewire tubing  914  may have an inner diameter of about 0.014 inches to about 0.017 inches, so the catheter system is compatible with a 0.014″ diameter guidewire. The guidewire tubing  914  may be made from a lubricious material such as Teflon, polypropylene or a polymer impregnated with Teflon. It may also be coated with a lubricous or hydrophilic coating. 
     The guidewire tip  915  may be cone shaped, bullet shaped or hemispherical on the front end. The largest diameter of the guidewire tip  915  is preferably approximately the same as the distal portion  903  of the outer tubular member  901 . The guidewire tip  915  preferably steps down to a diameter slightly smaller than the inside diameter of the outer sheath jacket  912 , so that the tip can engage the outer sheath jacket  912  and provide a smooth transition. In the illustrated embodiment, the guidewire tip  915  is connected to the guidewire tube  914 , and the guidewire lumen passes through a portion of the guidewire tip  915 . The proximal side of the guidewire tip  915  also has a cone, bullet or hemispherical shape, so that the guidewire tip  915  can easily be retraced back across the deployed implant  800 , and into the deployment catheter  900 . The guidewire tip  915  can be manufactured from a rigid polymer such as polycarbonate, or from a lower durometer material that allows flexibility, such as silicone. Alternatively, the guidewire tip  915  may be made from multiple materials with different durometers. For example, the portion of the guidewire tip  915  that engages the distal portion  903  of the outer tubular member  901  can be manufactured from a rigid material, while the distal and or proximal ends of the guidewire tip  915  are manufactured from a lower durmoter material. 
     Each PFL tubing  916  also extends throughout the length of the delivery catheter  900 . The proximal end of the PFL tubing  916  passes through the handle  907 , and has a luer lock  917  for connecting to fluid, gas or inflation media source. The distal end of the PFL tubing  916  extends past the distal end  906  of the inner tubular member  904  through the hypotube lumen. With reference to  FIG. 5C , in some embodiments, the PFL tubing  916  comprises a strain relief section  918  at the proximal end where the tubing  916  is connected to the luer lock  917 , and the strain relief section  918  serves to relieve the strain on the PFL tubing  916  while being maneuvered by the operator. The distal end of the PFL tubing  916  comprises a tip or needle  919  for connecting to the implant  800 . In some embodiments, the tip  919  may have a threaded section toward the end of the needle  919  (see  FIG. 5C ). In some embodiments, the PFL tubing  916  may have PFL marker(s)  920  at the distal end and/or proximal end of the tubing  916  for identification. 
     The PFL tubing  916  is designed to accommodate for the ease of rotation in a tortuous anatomy. The tubing  916  may be constructed using polyimide braided tube, Nitinol hypotube, or stainless steel hypotube. In a preferred embodiment, the PFL tubing  916  is made from braided polyimide, which is made of polyimide liner braided with flat wires, encapsulated by another polyimide layer and jacketed with prebax and nylon outer layer. In some embodiments, a Nitinol sleeve may be added to the proximal end of the PFL tubing  916  to improve torque transmission, kinks resistance and pushability. In some embodiments, the outside surface of the PFL tubing  916  and/or the inside surface of the lumens in the multilumen hypotube can also be coated with a lubricious silicone coating to reduce friction. In some embodiments, an inner lining material such as Teflon may be used on the inside surface of the lumens in the multilumen hypotube to reduce friction and improve performance in tortuous curves. Additionally, slippery coatings such as DOW 360, MDX silicone or a hydrophilic coating from BSI Corporation may be added to provide another form of friction reducing elements. This can provide a precision control of the PFL tubings  916  during positioning of the implant  800 . In some embodiments, the outside surface of the PFL tubing  916  can be jacketed and reflowed with an additional nylon 12 or Relsan AESNO layer to ensure a smooth finished surface. In some embodiments, anti-thrombus coating can also be put on the outside surface of the PFL tubing  916  to reduce the risk of thrombus formation on the tubing. 
     In some embodiments, the outer diameter of the catheter  900  measures generally about 0.030 inches to about 0.200 inches with a wall thickness of the outer tubular member  901  being about 0.005 inches to about 0.060 inches. In preferred embodiments, the outer diameter of the outer tubular member  901  is between about 0.215 and about 0.219 inches. In this embodiment, the wall thickness of the outer tubular member  901  is between about 0.005 inches and about 0.030 inches. The overall length of the catheter  900  ranges from about 80 centimeters to about 320 centimeters. In preferred embodiments, the working length of the outer tubular member  901  (from the distal end of the sheath jacket  912  to the location where the tubular member  901  is connected to the outer sheath handle  908 ) is about 100 cm to about 120 cm. In some embodiments, the inner diameter of the sheath jacket  912  is greater than or equal to about 0.218 inches, and the outer diameter of the sheath jacket  912  is less than or equal to about 0.241 inches. In a preferred embodiment, the outer diameter of the sheath jacket portion  912  is less than or equal to about 0.236 inches or 18 French. In some embodiments, the outer diameter of the PFL tubing  916  is less than or equal to about 0.0435 inches, and the length is about 140 cm to about 160 cm. 
     In the embodiments that employ a low crossing profile outer tubular member, a low profile inflatable implant in a retracted state is preferable for fitting into the sheath jacket  912 . The low crossing profile outer tubular member may comprise an outer sheath with a sheath jacket  912  having an outer diameter of 18 French or less. In some embodiments, the implant  800  comprises a tissue valve  104  with an expanded outer diameter greater than or equal to about 22 mm and a tissue thickness of greater than or equal to about 0.011 inches. The compressed diameter of the implant  800  may be less than or equal to about 6 mm or 18 French. The retracted implant  800  is generally loaded between the distal portion  903  of the outer tubular member  901  and the distal portion  906  of the inner tubular member  904 . The distal portion  903  of the outer tubular member  901  therefore forms a receptacle for the implant  800 . The implant  800  may be exposed or pushed out of the receptacle by holding the implant  800  stationary as the outer tubular member  901  is retracted. Alternatively, the outer tubular member  901  can be held stationary while the inner tubular member  904  is advanced and thereby pushing the implant  800  out of the receptable. 
     The delivery system also includes a loading tool base  925  that is configured to connect to the PFL tubing  916 . In some embodiments, the PFL tubing  916  can connect to the loading tool base  921  via a luer connection. With reference to  FIG. 7 , one end of the loading tool base  921  may be configured to have step edge  923   s . In some embodiments, the distal end of the loading tool base has three step edges  923 , each step edge  923  has a luer connector  924  for connecting the PFL tubing  916 . In some embodiments, the loading tool base  921  may also comprise at least two additional connectors  922  (e.g. additional luer connectors), each in fluid communication with one of the luer connector  924  on the stepped edges  923 , which would allow the introduction of fluid, gas or air into the implant  800  for testing purposes. For example, in the exemplified embodiment, once the PFL tubings  916  are connected to the loading tool base  921 , a liquid or air source can be connected to the loading tool base  921  via the additional connectors  922 . The liquid or air can then be introduced into the implant  800  through the loading tool base  921  and the PFL tubings  916 . 
     The step edges  923  on the loading tool base  921  allows the implant  800  to be collapsed or folded up tightly so it can be loaded into the sheath jacket  912  at the distal end of the outer tubular member  901 . When the proximal end of the PFL tubings  916  are connected to the loading tool base  921  and the distal end connected to the connection ports  809  of the implant  800 , the step edge connections pull the PFL tubings  916  in a way that creates an offset of the inflation valves  810  and/or the connection ports  809  in the inflation channels  808  when the implant  800  is folded or collapsed. By staggering the connection ports/inflation valves, the collapsed implant  800  can have a reduced cross-sectional profile. In some embodiments, the check valve  814  in the inflation channel is also staggered with the connection ports/inflation valves in the collapsed state. Accordingly, in one embodiment, the inflation valves  810  and/or the connection ports  809  are axially aligned when the valve is positioned within the deployment catheter in a collapsed configuration. That is, the inflation valves  810  and/or the connection ports  809  and/or check valve  814  are positioned such that they do not overlap with each other but are instead aligned generally with respect to the longitudinal axis of the deployment catheter. In this manner, the implant  800  can be collapsed into a smaller diameter as opposed to a configuration in which with the inflation valves  810  and/or the connection ports  809  and/or check valve  814  overlap each other in a radial direction, which can increase the diameter of the compressed implant  800 . In a similar manner, the channels  806  can be arranged positioned such hat they also do not overlap with each other as shown in  FIG. 12 . As shown in  FIG. 12 , the loading tool base  925  can be used to pull one end of the distal and proximal rings  807   a ,  807   b  in a proximal direction so as to align the inflation valves  810  and/or the connection ports  809  and/or check valve  814  axially as described above and/or align the channels so as to reduce the overlap between multiple channels  806 . 
     Method of Deployment 
     The implant  800  may be deployed in the aortic position using the low crossing profile delivery system and a minimally invasive procedure. In some embodiments, the method generally comprises gaining access to the aorta, most often through the femoral artery. The vascular access site is prepared according to standard practice, and the guidewire is inserted into the left ventricle through the vascular access. In some embodiments, an introducer is placed in the access vessel. A balloon valvuloplasty may optionally be performed in the case of aortic stenosis. 
     The catheter  900  carrying the cardiovascular prosthetic implant is translumenally advanced to a position proximate a native valve. After the delivery sheath or catheter  900  is inserted over the guidewire and advanced over the aortic arch and past the aortic valve, the implant  800  may be reveled or exposed by retracting the outer tubular member  901  partially or completely while holding the inner tubular member  904  stationary and allowing proper placement at or beneath the native valve. In some embodiments, the implant may also be reveled by pushing the inner tubular member  904  distally while holding the outer tubular member  901  stationary. Once the implant  800  is unsheathed, it may be moved proximally or distally, and the fluid or inflation media may be introduced to the cuff  802  providing shape and structural integrity. In some embodiments, the distal toroid of the inflatable cuff or inflatable structure is inflated first with a first liquid, and the implant  800  is positioned at the implantation cite using the links between the implant  800  and the catheter  900 . In some embodiments, no more than three links are present. In some embodiments, the links are PRL tubes  916 , which can be used to both control the implant  800  and to fill the inflatable cuff. 
     The deployment of the implant  800  can be controlled by the PFL tubes  916  that are detachably coupled to the implant  800 . The PFL tubes  916  are attached to the cuff  802  of the implant  800  so that the implant  800  can be controlled and positioned after it is removed from the sheath or delivery catheter  900 . Preferably, three PFL tubes  916  are used, which can provide precise control of the implant  800  PFL tubes  916  during deployment and positioning. The PFL tubes  916  can be used to move the implant  800  proximally and distally, or to tilt the implant  800  and change its angle relative to the native anatomy. 
     In some embodiments, the implant  800  contains multiple inflation valves  810  to allow the operator to inflate specific areas of the implant  800  with different amounts of a first fluid or a first gas. With reference to  FIGS. 8A-C , in some embodiments, the implant  800  is initially deployed partially in the ventricle  32  ( FIG. 8A ). The inflation channel  808  is filled partially, allowing the distal portion of the implant  800  to open to approximately its full diameter. The implant is then pulled back into position at or near the native valve  34  annulus ( FIG. 8B ). In some embodiments, the distal toroid  807   b  is at least partially inflated first, and the cardiovascular prosthetic implant  800  is then retracted proximally for positioning the cuff across the native valve  34 . The distal ring  807   b  seats on the ventricular side of the aortic annulus, and the implant  800  itself is placed just above the native valve  34  annulus in the aortic root. At this time, the PFL tubes  916  may act to help separate fused commissures by the same mechanism a cutting balloon can crack fibrous or calcified lesions. Additional inflation fluid or gas may be added to inflate the implant  800  fully, such that the implant  800  extends across the native valve annulus extending slightly to either side (See  FIG. 8C ). The PFL tubes  916  provide a mechanism for force transmission between the handle of the deployment catheter  900  and the implant  800 . By moving all of the PFL tubes  916  together or the inner tubular member  904 , the implant  800  can be advanced or retracted in a proximal or distal direction. By advancing only a portion of the PFL tubes  916  relative to the other PFL tubes  916 , the angle or orientation of the implant  800  can be adjusted relative to the native anatomy. Radiopaque markers on the implant  800  or on the PFL tubes  916 , or the radio-opacity of the PFL tubes  916  themselves, can help to indicate the orientation of the implant  800  as the operator positions and orients the implant  800 . 
     In some embodiments, the implant  800  has two inflation valves  810  at each end of the inflation channel  808  and a check valve  811  in the inflation channel  808 . The check valve  811  is positioned so the fluid or gas can flow in the direction from the proximal toroid  807   a  to the distal toroid  807   b . In some embodiments, the implant  800  is fully inflated by pressurizing the endoflator attached to the first PFL tube  916  that is in communication with the first inflation valve  810  that leads to the proximal toroid  807   a , while the endoflator attached to the second inflation valve  810  that is in communication with the distal toroid  807   b  is closed. The fluid or gas can flow into the distal toroid  807   b  through the one-way check valve. The proximal toroid  807   a  is then deflated by de-pressurizing the endoflator attached to the second inflation valve. The distal toroid  807   b  will remain inflated because the fluid or gas cannot escape through the check valve  811 . The implant  800  can then be positioned across the native annulus. Once in the satisfactory placement, the proximal toroid  807   a  can then be inflated again. 
     In some embodiments, the implant  800  may only have one inflation valve. When the inflation channel  808  is inflated with the first fluid or gas, the proximal portion of the implant  800  may be slightly restricted by the spacing among the PFL tubes  916  while the distal portion expands more fully. In general, the amount that the PFL tubes  916  restricts the diameter of the proximal end of the implant  800  depends on the length of the PFL tubes  916  extend past the outer tubular member  901 , which can be adjusted by the operator. In other embodiments, burst discs or flow restricters are used to control the inflation of the proximal portion of the implant  800 . 
     The implant  800  can also be deflated or partially deflated for further adjustment after the initial deployment. As shown in  FIG. 9A , the implant  800  is partially deployed and the PFL tubes  916  used to seat the implant  800  against the native aortic valve  34 . The implant  800  can then be fully deployed as in shown in  FIG. 9B  and then tested as shown in  FIG. 9C . If justified by the test, the implant  800  can be deflated and moved as shown in  FIG. 9D  to a more optimum position. The implant  800  can then be fully deployed and released from the control wires as shown in  FIG. 9E . 
     As discussed above, in some embodiments, the first inflation fluid or gas can be displaced by an inflation media that can harden to form a more permanent support structure in vivo. Once the operator is satisfied with the position of the implant  800 , the PFL tubes  916  are then disconnected, and the catheter is withdrawn leaving the implant  800  behind (see  FIG. 8C ), along with the hardenable inflation media. The inflation media is allowed to solidify within the inflatable cuff. The disconnection method may included cutting the attachments, rotating screws, withdrawing or shearing pins, mechanically decoupling interlocked components, electrically separating a fuse joint, removing a trapped cylinder from a tube, fracturing a engineered zone, removing a colleting mechanism to expose a mechanical joint or many other techniques known in the industry. In modified embodiments, these steps may be reversed or their order modified if desired. 
     The above-describe method generally describes an embodiment for the replacement of the aortic valve. However, similar methods could be used to replace the pulmonary valve or the mitral or tricuspid valves. For example, the pulmonary valve could be accessed through the venous system, either through the femoral vein or the jugular vein. The mitral valve could be accessed through the venous system as described above and then trans-septaly accessing the left atrium from the right atrium. Alternatively, the mitral valve could be accessed through the arterial system as described for the aortic valve, additionally the catheter can be used to pass through the aortic valve and then back up to the mitral valve. Additional description of mitral valve and pulmonary valve replacement can be found in U.S. Patent Publication No. 2009/0088836 to Bishop et al. 
     Implant Recovery 
     Current valve systems are often deployed through a stent-based mechanism where the valve is sewn to the support structure. In the inflated embodiments described herein, the structure is added to the implant secondarily via the inflation fluid. This allows the user to inflate or pressurize the implant  800  with any number of media including one that will solidify. As such, if the operator desires, the implant  800  can be moved before the inflation media is solidified or depressurization can allow for movement of the implant within the body. Since catheter based devices tend to be small in diameter to reduce trauma to the vessel and allow for easier access to entry, it often difficult to remove devices such as stents once they have been exposed or introduced into the vasculature. However, as will be explained below, a device described herein enables a percutaneous prosthetic aortic valve to be recovered from the body and reintroduced retrograde to the introducer. 
     With reference to  FIGS. 10A-C , the deployment control device also provides a method for retracting the implant  800  back into the introducer if the result is not satisfactory, or if the sizing of the implant could be optimized. Thus, after the implant  800  is fully or partially deployed ( FIG. 10A ), in addition to providing a mechanism to transmit axial force to the implant  800 , the PFL tubes  916  described above provide a guide or ramp to pull the implant  800  back into the introducer as it is retracted as shown in  FIGS. 10B and 10C . In some embodiments, the outer tubular member  901  is retracted out of the vessel while leaving the inner tubular member  904  still attached to the implant  800  prior to introducing the recovery catheter  930 . 
     To recapture an inflatable implant  800 , the implant is first deflated ( FIG. 10B ). In some embodiment, the implant  800  may be retracted to the tip of the inner tubular member  904  by pulling the PFL tubing  916  proximally, and the implant  800  and the delivery catheter  900  are then retracted to the tip of the introducer. The inner sheath handle  907  may be removed by unthreading the distal portion and sliding off at the proximal end of the delivery catheter  900 . In some embodiments, the luer connections  917  on the proximal end of the PFL tubing  916  may be cut off for the removal of the inner sheath handle  907 . Optionally a pushing tube can be loaded over the guidewire and PFL tubing until adjacent to the proximal end of the inner tubular member  904 . The outer tubular member  901  can then be removed from the delivery catheter system, while keeping the implant  800  stationary. 
     The recovery catheter  930  can then be advanced over the guidewire and the inner tubular member  904 . Once the recovery catheter  930  is proximate to the implant, the recovery sheath  931  is retracted to expose the basket section  933 . The implant  800  can then be retracted into the basket section  933  ( FIG. 10C ). Once the implant  800  is completely inside the basket section  933 , in some embodiments, the PFL tubes  916  are adjusted to offset the end valves  810  in the implant  800  to allow more compact fold. The recovery system  930  is then slowly pulled back through the introducer and out of the patient. 
       FIG. 11  illustrates one embodiment of a recovery catheter  930  for recapturing an implant  800 . As shown, the recovery catheter  930  comprises an outer recovery sheath  931 . The outer recovery sheath  931  is inserted over the inner shaft  932 . The inner shaft  932  comprises a basket structure  933 , which is coupled to the distal end of the inner shaft  932  and is configured to capture the implant into the outer recovery sheath  931  without harm to the patient. Relative movement of the inner shaft  932  with respect to the outer recovery sheath  931  would expose the basket  933  when introduced into the body. By pulling the implant  800  into the basket section  933  it may be safely reintroduced into the introducer or outer recovery sheath  931 . The basket  933  allows the implant to be guided into an introducer without harm or worry of the implant being tethered or compiled to a larger diameter where it may not fit into the inner diameter of a sheath. 
     The outer recovery sheath  931  is attached to the outer recovery handle or hub  935  at the proximal end, while the inner shaft  932  is attached to the inner recovery handle or hub  934  at the proximal end. A hemostasis valve (not shown) is preferably disposed in each of the inner and outer recovery handles  934  and  935 . Also on the inner recovery handle  934 , a flush port  936  and stop-cock can be provided for fluid introduction. In one embodiment, the inner shaft  932  would have a length of about 40 to 60 centimeters and a diameter of about 2 to about 10 millimeters. In a preferred embodiment, the outer diameter of the inner shaft  932  is less than or equal to 0.207″. The basket section  933  may be constructed with materials such as polymeric strands or Nitinol, stainless steel or MP35N wire and attached by glue or thermal bonding techniques know in the industry. This wire, strand or ribbon may have a diameter or dimension of about 0.002 to 0.020 of an inch. The set or expanded shape would be about 1.00 to 1.50 inches and the length of the basket section  933  would measure about 6 to 9 inches in length. In another embodiment, the basket section  933  is made out of a fabric, where the fabric basket may contain a feature such as a preshaped wire or a balloon to facilitate its opening. 
     The basket section  933  can be formed by heat setting or other manners into a cone shape with a free diameter slightly larger than the patients aorta. In another embodiment, the braided basket is manufactured from loops of wire so that the cut ends of the wire are all located at the proximal end of the basket. The wires used to manufacture the basket  933  preferably have a diameter from 0.002 in to 0.020 in. The wires may also be replaced by ribbons having a thickness between 0.002 in and 0.020 in and a width between 0.003 in and 0.030 in. The diameter of the small end of the basket is preferably between 0.007 in and 0.3 in the basket is preferably be capable of collapsing to a diameter small enough to pass through the desired introducer size. The large end of the basket section preferably expands to a diameter similar to or slightly larger than the typical human aorta, or 0.75 in to 1.50 in. 
     The various methods and techniques described above provide a number of ways to carry out the invention. Of course, it is to be understood that not necessarily all objectives or advantages described may be achieved in accordance with any particular embodiment described herein. Thus, for example, those skilled in the art will recognize that the methods may be performed in a manner that achieves or optimizes one advantage or group of advantages as taught herein without necessarily achieving other objectives or advantages as may be taught or suggested herein. 
     Furthermore, the skilled artisan will recognize the interchangeability of various features from different embodiments disclosed herein. Similarly, the various features and steps discussed above, as well as other known equivalents for each such feature or step, can be mixed and matched by one of ordinary skill in this art to perform methods in accordance with principles described herein. Additionally, the methods which is described and illustrated herein is not limited to the exact sequence of acts described, nor is it necessarily limited to the practice of all of the acts set forth. Other sequences of events or acts, or less than all of the events, or simultaneous occurrence of the events, may be utilized in practicing the embodiments of the invention. 
     Although the invention has been disclosed in the context of certain embodiments and examples, it will be understood by those skilled in the art that the invention extends beyond the specifically disclosed embodiments to other alternative embodiments and/or uses and obvious modifications and equivalents thereof. Accordingly, the invention is not intended to be limited by the specific disclosures of preferred embodiments herein