Abstract:
Controlled deployable medical devices that are retained inside a body passage and in one particular application to vascular devices used in repairing arterial dilations, e.g., aneurysms. Such devices can be adjusted during deployment, thereby allowing at least one of a longitudinal or radial re-positioning, resulting in precise alignment of the device to an implant target site.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application claims priority to provisional application Ser. No. 61/058,776, filed Jun. 4, 2008. 
     
    
     BACKGROUND OF THE INVENTION 
       [0002]    1. Field of the Invention 
         [0003]    The invention relates generally to devices that are retained inside a body passage and in one particular application to vascular devices used in repairing arterial dilations, e.g., aneurysms. More particularly, the invention is directed toward devices that can be adjusted during deployment, thereby allowing at least one of a longitudinal or radial re-positioning of the device prior to final placement of the device. 
         [0004]    2. Discussion of the Related Art 
         [0005]    The invention will be discussed generally with respect to deployment of a bifurcated stent graft into the abdominal aorta but is not so limited and may apply to device deployment into other body lumens. When delivering a stent graft by intraluminal or endovascular methods, it is important to know the precise location of the device in the vasculature. Controlling this precise location is particularly important when the device is intended to be deployed in close proximity to branch vessels or adjacent to weakened portions of the aortic wall. Typical stent grafts used to repair an aortic aneurysm incorporate a proximal (i.e. portion of the stent graft closest to the heart) anchoring system intended to limit longitudinal displacement of the stent graft. Often this anchoring system must be precisely placed to avoid occlusion of a branch vessel or to avoid placement within a compromised and damaged portion of the aortic wall. 
         [0006]    An improved delivery system for such stent grafts would include a means for allowing precise longitudinal and rotational placement of the stent graft and anchoring system. The precise position of the stent graft and anchoring system would be adjusted and visualized prior to full deployment of the device. Ideally the delivery system would allow the device to be repositioned if the prior deployment position was undesirable. 
       SUMMARY OF THE INVENTION 
       [0007]    The present invention is directed to a controlled deployable medical device and method of making the same that substantially obviates one or more of the problems due to limitations and disadvantages of the related art. 
         [0008]    A first embodiment of the present invention provides an apparatus comprising a catheter having a proximal end portion and distal end portion, a stent member arranged on the proximal end portion of the catheter, the stent member has an inner surface and an outer surface. A graft member can be arranged about at least a portion of the stent member. Moreover, a tube extends from the catheter proximal end portion to the distal end portion. A first movable element, having a first and second end, is in communication with the stent member, wherein the first and second end of the first movable element are capable of extending out the distal end portion of the tube and the first movable element is capable of radially compressing at least a portion of the stent member. 
         [0009]    In another embodiment, the present invention provides an apparatus comprising a catheter having a proximal end portion and distal end portion, a stent member arranged on the proximal end portion of the catheter, the stent member has an inner surface, an outer surface. A graft member can be arranged about at least a portion of the stent member. Moreover, a tube having a continuous lumen extends from the proximal end portion to a distal end portion of the catheter. A release pin is contained within the tube lumen and extends from the catheter proximal end portion to a distal end portion of the catheter. 
         [0010]    In another embodiment, the present invention provides an apparatus comprising a catheter having a proximal end portion and distal end portion. A stent member is arranged on the proximal end portion of the catheter, the stent member has an inner surface and an outer surface. A graft member can be arranged about at least a portion of the stent member. A first sheath material covers at least a portion of the stent member. The first sheath material is capable of holding the stent member at a first dimension. A second sheath material covers at least a portion of the stent member. The second sheath material is capable of holding the stent member at a second dimension, with the second dimension being greater than the first dimension. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS  
         [0011]    The accompanying drawings are included to provide a further understanding of the invention and illustrate certain aspects of the invention. 
           [0012]    In the drawings: 
           [0013]      FIG. 1A  is a medical apparatus according to an embodiment of the invention. 
           [0014]      FIG. 1B  is an enlarged simplified view of the medical apparatus according to an embodiment of the invention. 
           [0015]      FIG. 1C  is a medical apparatus according to an embodiment of the invention. 
           [0016]      FIG. 1D  is an enlarged simplified view of the medical apparatus according to a second embodiment of the invention. 
           [0017]      FIG. 2A  is a medical apparatus according to an embodiment of the invention. 
           [0018]      FIG. 2B  is an enlarged simplified view of a medical apparatus according to an embodiment of the invention. 
           [0019]      FIG. 2C  is a medical apparatus according to an embodiment of the invention. 
           [0020]      FIG. 2D  is an enlarged simplified view of a medical apparatus according to an embodiment of the invention. 
           [0021]      FIG. 3A  is a medical apparatus according to an embodiment of the invention. 
           [0022]      FIG. 3B  is an enlarged simplified view of a medical apparatus according to an embodiment of the invention. 
           [0023]      FIG. 3C  is an enlarged simplified view of a medical apparatus according to an embodiment of the invention. 
           [0024]      FIG. 4A  is a medical apparatus according to an embodiment of the invention. 
           [0025]      FIG. 4B  is an enlarged simplified view of a medical apparatus according to an embodiment of the invention. 
           [0026]      FIG. 5A  is a medical apparatus according to an embodiment of the invention. 
           [0027]      FIG. 5B  is an enlarged simplified view of a medical apparatus according to an embodiment of the invention. 
           [0028]      FIG. 6A  is a medical apparatus according to an embodiment of the invention. 
           [0029]      FIG. 6B  is an enlarged simplified view of a medical apparatus according to an embodiment of the invention. 
           [0030]      FIG. 7A  is a medical apparatus according to an embodiment of the invention. 
           [0031]      FIG. 7B  is an enlarged simplified view of a medical apparatus according to an embodiment of the invention. 
           [0032]      FIGS. 8A-8C  is a medical apparatus according to an embodiment of the invention. 
           [0033]      FIG. 9A  is an apparatus according to an embodiment of the invention. 
           [0034]      FIG. 9B  is a cross-sectional view of  FIG. 9A  along line A to A′. 
           [0035]      FIGS. 10A-10H  illustrates a deployment procedure of an apparatus according to  FIGS. 2A-2B . 
       
    
    
     DETAILED DESCRIPTION  
       [0036]    The invention relates generally to a novel medical apparatus that includes a device capable of being retained inside a body passage and in one particular application to vascular devices. More particularly, the invention is directed toward devices that can be adjusted during deployment, thereby allowing at least one of a longitudinal or radial re-positioning of the device. 
         [0037]    In an embodiment of the invention, the medical apparatus includes a catheter assembly having a proximal end portion and distal end portion. A hub can optionally be arranged on the distal end portion of the catheter assembly. A stent is arranged on the proximal end portion of the catheter. The stent has an inner surface and an outer surface. The stent can be any suitable configuration. In one embodiment, the stent is configured from multiple turns of an undulating element. A graft member can be arranged about at least a portion of the stent. The stent may be self-expandable, balloon-expandable or a combination of self-expandable and balloon-expandable. 
         [0038]    A tube extends from the proximal end portion to the distal end portion of the catheter. A first movable element, having a first and second end, is arranged around the outer surface of the stent. The first and second end of the first movable element are capable of extending out the distal end portion of the tube and the first movable element is capable of radially compressing at least a portion of the stent. 
         [0039]    Optionally, a second movable element can be in communication with the first movable element, wherein the second movable element is arranged around the outer surface of stent and the first movable element is looped over the second movable element. A sheath material can cover at least a portion of the stent, wherein the sheath material is capable of holding the stent at a first diameter. A filament can surround the stent and a pin can extend from the tube and is capable of holding the filament surrounding the stent at a second diameter which is greater than the first diameter. The pin extending from the tube is capable of releasing the filament surrounding the stent to a third diameter which is greater than the second diameter. 
         [0040]    In some embodiments, the stents can be used to at least fix the medical apparatus inside a portion of patient&#39;s anatomy. The stent can be constructed from materials that are flexible and strong. The stent can be formed from, for example, degradable bioabsorable materials, biodigestible materials, polymeric materials, metallic materials and combinations thereof. In addition, these materials may be reinforced and/or coated with other materials, such as polymeric materials and the like. The coating may be chosen to reduce acidic or basic effects of the gastrointestinal tract, e.g., with a thermoplastic coating such as ePTFE and the like. 
         [0041]    The stents can be fabricated using any suitable methods and materials. For example, stents can be fabricated according to the teachings as generally disclosed in U.S. Pat. No. 6,042,605 issued to Martin, et al., U.S. Pat. No. 6,361,637 issued to Martin, et al. and U.S. Pat. No. 6,520,986 issued to Martin, et al. For example, stents can have various configurations as known in the art and can be fabricated, for example, from cut tubes, wound wires (or ribbons), flat patterned sheets rolled into a tubular form, combinations thereof, and the like. Stents can be formed from metallic, polymeric or natural materials and can comprise conventional medical grade materials such as nylon, polyacrylamide, polycarbonate, polyethylene, polyformaldehyde, polymethylmethacrylate, polypropylene, polytetrafluoroethylene, polytrifluorochlorethylene, polyvinylchloride, polyurethane, elastomeric organosilicone polymers; metals such as stainless steels, cobalt-chromium alloys and nitinol and biologically derived materials such as bovine arteries/veins, pericardium and collagen. Stents can also comprise bioresorbable materials such as poly(amino acids), poly(anhydrides), poly(caprolactones), poly(lactic/glycolic acid) polymers, poly(hydroxybutyrates) and poly(orthoesters). 
         [0042]    The stents can be formed into a variety of different geometric configurations having constant and/or varied thickness as known in the art. The geometric configurations may include many conventional stent configurations such as a helically wrapped stent, z-shape stent, tapered stent, coil stent, combinations thereof, and the like. The stents can be formed in a variety of patterns, such as, a helix pattern, ring pattern, combinations thereof, and the like. 
         [0043]    Grafts can have various configurations as known in the art and can be fabricated, for example, from tubes, sheets or films formed into tubular shapes, woven or knitted fibers or ribbons or combinations thereof. Graft materials can include, for example, conventional medical grade materials such as nylon, polyester, polyethylene, polypropylene, polytetrafluoroethylene, polyvinylchloride, polyurethane and elastomeric organosilicone polymers. 
         [0044]    Stents can be used alone or in combination with graft materials. Stents can be configured on the external or internal surface of a graft or may be incorporated into the internal wall structure of a graft. Stent or stent grafts can be delivered endoluminally by various catheter based procedures known in the art. For example self-expanding endoluminal devices can be compressed and maintained in a constrained state by an external sheath. The sheath can be folded to form a tube positioned external to the compressed device. The sheath edges can be sewn together with a deployment cord that forms a “chain stitch”. To release and deploy the constrained device, one end of the deployment cord can be pulled to disrupt the chain stitch, allowing the sheath edges to separate and release the constrained device. Constraining sheaths and deployment cord stitching can be configured to release a self-expanding device in several ways. For example a constraining sheath may release a device starting from the proximal device end, terminating at the distal device end. In other configurations the device may be released starting from the distal end. Self expanding devices may also be released from the device center as the sheath disrupts toward the device distal and proximal ends. 
         [0045]    Details relating to constraining sheath materials, sheath methods of manufacture and stent graft compression techniques can be found in, for example, U.S. Pat. No. 6,352,561 issued to Leopold, et al., and U.S. Pat. No. 6,551,350 issued to Thornton, et al. 
         [0046]    The catheter and hub assemblies can comprise conventional medical grade materials such as nylon, polyacrylamide, polycarbonate, polyethylene, polyformaldehyde, polymethylmethacrylate, polypropylene, polytetrafluoroethylene, polytrifluorochlorethylene, polyether block amide or thermoplastic copolyether, polyvinylchloride, polyurethane, elastomeric organosilicone polymers, and metals such as stainless steels and nitinol. 
         [0047]    Turning to the figures,  FIG. 1A  is a medical apparatus according to an embodiment of the invention.  FIG. 1B  is an enlarged simplified view of a portion of the medical apparatus shown in  FIG. 1A . 
         [0048]    Referring to  FIGS. 1A and 1B , the medical apparatus is generally depicted as reference numeral  100 A. The medical apparatus  100 A includes catheter assembly  102 , stent  104  arranged on the proximal end portion of the catheter assembly  102 . The stent  104  has an inner surface, an outer surface, and in this embodiment is configured from multiple turns of an undulating element  105 . The undulating element  105  can be configured, for example, in a ring or helical pattern. 
         [0049]    The stent  104  has a proximal end portion  106  and distal end portion  108 . The distal end portion  108  is formed into a branch having a first leg  110  and a second leg  112 . 
         [0050]    A graft member  114  is arranged about the stent  104 . 
         [0051]    The stent  104  and graft member  114  are constrained into a compacted delivery state by a first sheath  116  and second sheath  118 . As shown in  FIG. 1A , the first sheath  116  has been released, allowing at least a portion of the stent  104  to expand as shown. The second sheath  118  is coupling the second leg  112  to the catheter assembly  102  as shown. 
         [0052]    A tube  120  extends from a proximal end portion to a distal end portion of the catheter assembly  102 . In the figure, the tube  120  is positioned adjacent the outer surface of the stent  104  and graft  114 . The tube  120  is attached to the catheter assembly  102  and not attached to the stent  104  or graft  114 . A movable element  122  (e.g., a fiber cord, string, wire, etc.) having a first end  124  and second end  126  surrounds the stent  104  and graft member  114 . The first end  124  and second end  126  of the movable element  122  extend out a distal end portion of the tube  120 . For example, the movable element  122  is threaded through the tube from a distal end to a proximal end and is looped around the proximal end portion  106  of the stent  104  and graft member  114 . As shown in  FIG. 1B , by pulling the first end  124  and the second end  126  in a distal direction the movable element  122  is capable of radially compressing at least a portion of the stent  104  as indicated by arrows  128 . 
         [0053]      FIG. 1C  is a medical apparatus according to an embodiment of the invention.  FIG. 1D  is an enlarged simplified view of a portion of the medical apparatus shown as  FIG. 1C . 
         [0054]    Referring to  FIGS. 1C and 1D , the medical apparatus is generally depicted as reference numeral  100 B. The medical apparatus of  FIGS. 1C and 1D  is similar to the medical apparatus as shown in  FIGS. 1A and 1B . The medical apparatus includes catheter assembly  102 , stent  104  arranged on the proximal end portion of catheter assembly  102 . Stent  104  has an inner surface, an outer surface, and is configured from multiple turns of an undulating element  105 . The undulating element  105  may be configured, for example, in a ring or helical pattern. 
         [0055]    The stent  104  has a proximal end portion  106  and distal end portion  108 . The distal end portion  108  is formed into a branch having a first leg  110  and a second leg  112 . 
         [0056]    A graft member  114  is arranged about the stent  104 . 
         [0057]    The stent  104  and graft member  114  are constrained into a compacted delivery state by a first sheath  116  and second sheath  118 . As shown in  FIG. 1C , the first sheath  116  has been released allowing at least a portion of the stent to expand as shown. The second sheath  118  is coupling the second leg  112  to the catheter assembly  102  as shown. 
         [0058]    A tube  120  extends from a proximal end portion to a distal end portion of the catheter assembly  102 . The tube  120  is positioned adjacent the outer surface of the stent  104  and graft  114 . The tube  120  is attached to the catheter assembly  102  and not attached to the stent  104  or graft  114 . A movable element  122 A having a first end  124  and second end  126  surrounds the stent  104  and graft member  114 . The first end  124  and second end  126  of the movable element  122 A extend out a distal end portion of the tube  120 . For example, the movable element  122 A is threaded through the tube from a distal end to a proximal end and is looped around the proximal end portion  106  of the stent  104  and graft member  114 . 
         [0059]    Moreover, an additional movable element  122 B having first end  132  and second end  134  surrounds the stent  104  and graft member  114 . The first end  132  and second end  134  of the additional movable element  122 B extend out a distal end portion of the tube  120 . The additional movable element  122 B is threaded through the tube from a distal end to an intermediate opening  136  in the tube  120  and is looped around an intermediate portion of the stent  104  and graft member  114 . As shown in  FIG. 1D , by pulling the ends of the moveable elements in a distal direction the movable element  122 A and the additional movable element  122 B are capable of radially compressing at least a portion of the stent  104  as indicated by arrows  128 . It should be understood that additional moveable elements can be provided. 
         [0060]      FIG. 2A  is a medical apparatus according to an embodiment of the invention, shown in a partially deployed state.  FIG. 2B  is an enlarged simplified view of a portion of the medical apparatus shown in  FIG. 2A . 
         [0061]    Referring to  FIGS. 2A and 2B , the medical apparatus is generally depicted by reference numeral  200 A. The medical apparatus  200 A includes a catheter assembly  202 , and stent  204  arranged on the proximal end portion of the catheter assembly  202 . The stent  204  has an inner surface, an outer surface, and is configured from multiple turns of an undulating element  205 . The undulating element  205  can be configured, for example, in a ring or helical pattern. 
         [0062]    The stent  204  has a proximal end portion  206  and distal end portion  208 . The distal end portion  208  is formed into a branch having a first leg  210  and a second leg  212 . 
         [0063]    A graft member  214  is arranged about the stent  204 . 
         [0064]    The stent  204  and graft member  214  are constrained into a compacted delivery state by a first sheath  216  and second sheath  218 . As shown in  FIG. 2A , the first sheath  216  has been released allowing at least a portion of the stent to expand. The second sheath  218  is coupling the second leg  212  to the catheter assembly  202  as shown. 
         [0065]    A tube  220  extends from a proximal end portion to a distal end portion of the catheter assembly  202 . In this embodiment, the tube  220  is positioned adjacent the outer surface of the stent  204  and graft  214 . In this embodiment, the tube  220  is attached to the catheter assembly  202  and not attached to the stent  204  or graft  214 . 
         [0066]    A second movable element  236  is in communication with a first movable element  222 . The second movable element  236  surrounds the stent  204  and the first movable element  222  is looped through the second movable element  236 . 
         [0067]    The first end  224  and second end  226  of the first movable element  222  extend out a distal end portion of the tube  220 . For example, the first movable element  222  is threaded through the tube from a distal end to a proximal end and is looped through the second movable element  236 . 
         [0068]    As shown in  FIG. 2B , when the two ends  224  and  226  of the first movable element are pulled in a distal direction, the movable element  222  pulls on the second movable element  236 , radially compressing at least a portion of the stent  204  as indicated by arrows  228 . 
         [0069]      FIG. 2C  is a medical apparatus according to an embodiment of the invention.  FIG. 2D  is an enlarged simplified view of a portion of the medical apparatus shown in  FIG. 2C . 
         [0070]    Referring to  FIGS. 2C and 2D , the medical apparatus is generally depicted by reference numeral  200 B. The medical apparatus of  FIGS. 2C and 2D  is similar to the medical apparatus as shown in  FIGS. 2A and 2B . 
         [0071]    Shown in  FIGS. 2C and 2D , a second movable element  236 A is in communication with a first movable element  222 A. The second movable element  236 A surrounds the stent  204  and the first movable element  222 A is looped through the second movable element  236 A. 
         [0072]    An additional first movable element  222 B along with an additional second movable element  236 B are incorporated into the medical apparatus  200 B. 
         [0073]    As shown in  FIG. 2D , when tension is applied to the two ends  224  and  226  of the first movable element  222 A, the first movable element  222 A pulls on the second movable element  236 A, radially compressing at least a portion of the stent  204  as indicated by arrows  228 . Similarly, when tension is applied to the two ends  232  and  234  of the additional first movable element  222 B, the additional first movable element  222 B pulls on the additional second movable element  236 B, radially compressing at least a portion of the stent  204  as indicated by arrows  228 . 
         [0074]      FIG. 3A  is a medical apparatus according to an aspect of the invention.  FIG. 3B  is an enlarged simplified view of a portion of the medical apparatus shown in  FIG. 3A . 
         [0075]    Referring to  FIGS. 3A and 3B , the medical apparatus is generally depicted by reference numeral  300 A. The medical apparatus  300 A includes a catheter assembly  302 , and stent  304  arranged on the proximal end portion of the catheter assembly  302 . The stent  304  has an inner surface, an outer surface, and is configured from multiple turns of an undulating element  305 . The undulating element  305  may be configured in a ring or helical pattern. 
         [0076]    The stent  304  has a proximal end portion  306  and distal end portion  308 . The distal end portion  308  is formed into a branch having a first leg  310  and a second leg  312 . 
         [0077]    A graft  314  is arranged about the stent  104 . 
         [0078]    In one preferred embodiment, the stent  304  and graft  314  are constrained into a compacted delivery state by a first sheath  316  and second sheath  318 . As shown in  FIG. 3A , the first sheath  316  has been released allowing at least a portion of the stent  304  to expand as shown. The second sheath  318  is coupling the second leg  312  to the catheter assembly  302  as shown. 
         [0079]    A tube  320  extends from a proximal end portion to a distal end portion of the catheter assembly  302 . The tube  320  is positioned within and surrounded by the stent  304 . The tube  320  is attached to the catheter assembly  302  and not attached to the stent  304  or graft  314 . A movable element  322  having a first end  324  and second end  326  surrounds the stent  304  and graft  314 . The first end  324  and second end  326  of the movable element  322  extend out a distal end portion of the tube  320 . The movable element  322  is threaded through the tube from a distal end to a proximal end and is looped around the proximal end portion  306  of the stent  304  and graft  314 . A further embodiment for “surrounding” the stent with the moveable element includes threading the moveable element  322  through the graft  314  or through the stent  304  as shown in  FIG. 3B . As shown in  FIG. 3B , the movable element  322  is capable of radially compressing at least a portion of the stent  304  as indicated by arrows  328  when tension is applied to the movable element ends  324  and  326 . Additional movable elements may be added similar to those configurations described in  FIGS. 1D and 2D . 
         [0080]      FIG. 3C  is an enlarged simplified view of a portion of a medical apparatus according to an embodiment of the invention. As shown in  FIG. 3C , second movable element  336  is in communication with first movable element  322 . The second movable element  336  surrounds the stent member  304  and the first movable element  322  is looped through the second movable element  336 . The second movable element  336  may also be threaded through the graft  314  or threaded through the stent  304  as shown in  FIG. 3C . 
         [0081]    The first end  324  and second end  326  of the first movable element  322  extend out a distal end portion of the tube  320 . For example, the first movable element  322  is threaded through the tube from a distal end to a proximal end and is looped through the second movable element  336 . 
         [0082]    As shown in  FIG. 3C , when tension is applied to the two ends  324  and  326  of the first movable element  322 , the first movable element  322  pulls on the second movable element  336 , radially compressing at least a portion of the stent  304  as indicated by arrows  328 . Additional movable elements may be added similar to those configurations described in  FIGS. 1D and 2D . 
         [0083]      FIG. 4A  is a medical apparatus according to an embodiment of the invention.  FIG. 4B  is an enlarged simplified view of a portion of the the medical apparatus shown in  FIG. 4A . 
         [0084]    Referring to  FIGS. 4A and 4B , the medical apparatus is generally depicted by reference numeral  400 . The medical apparatus  400  includes a catheter assembly  402 , and stent  404  arranged on the proximal end portion of the catheter assembly  402 . The stent  404  has an inner surface, an outer surface, and is configured from multiple turns of an undulating element  405 . The undulating element  405  may be configured in a ring or helical pattern. 
         [0085]    The stent  404  has a proximal end portion  406  and distal end portion  408 . The distal end portion  408  is formed into a branch having a first leg  410  and a second leg  412 . 
         [0086]    A graft  414  is arranged about the stent  404 . 
         [0087]    The stent  404  and graft  414  are constrained into a compacted delivery state by a first sheath  416  and second sheath  418 . As shown in  FIG. 4A , the first sheath  416  has been released allowing at least a portion of the stent  404  to expand as shown. The second sheath  418  is coupling the second leg  412  to the catheter assembly  402  as shown. 
         [0088]    A tube  420  extends from a proximal end portion to a distal end portion of the catheter assembly  402 . The tube  420  is positioned adjacent the outer surface of the stent  404  and graft  414 . The tube  420  is attached to the catheter assembly  402  and not attached to the stent  404  or graft  414 . A second movable element  436  is in communication with a first movable element  422 . The second movable element  436  surrounds the stent  404 . The second movable element  436  is looped through the first movable element  422 . A release pin  450  is threaded through the second movable element  436 , thereby releasably attaching the second movable element  436  to the first movable element  422 . 
         [0089]    The first end  424  and second end  426  of the first movable element  422  extend out a distal end portion of the tube  420  along with the distal end of the release pin  450 . 
         [0090]    As shown in  FIG. 4B , when tension is applied to the two ends  424  and  426  of the first movable element  422 , the first movable element  422  pulls on the second movable element  436 , radially compressing at least a portion of the stent as previously shown, for example, in  FIG. 2B . 
         [0091]    The release pin  450  can be translated in a distal direction as shown by direction arrow  452 , thereby releasing the second movable element  436  from the first movable element  422 . 
         [0092]      FIG. 5A  is a medical apparatus according to an embodiment of the invention.  FIG. 5B  is an enlarged simplified view of a portion of the medical apparatus shown in  FIG. 5A . 
         [0093]    Referring to  FIGS. 5A and 5B , the medical apparatus is generally depicted as reference numeral  500 . The medical apparatus  500  includes a catheter assembly  502 , and stent  504  arranged on the proximal end portion of the catheter assembly  502 . The stent  504  has an inner surface, an outer surface, and is configured from multiple turns of an undulating element  505 . The undulating element  505  may be configured in a ring or helical pattern. 
         [0094]    The stent  504  has a proximal end portion  506  and distal end portion  508 . The distal end portion  508  is formed into a branch having a first leg  510  and a second leg  512 . 
         [0095]    A graft  514  is arranged about the stent  504 . 
         [0096]    In a preferred embodiment, the stent  504  and graft  514  are constrained into a compacted delivery state by a first sheath  516  and second sheath  518 . As shown in  FIG. 5A , the first sheath  516  has been released allowing at least a portion of the stent  504  to expand as shown. The second sheath  518  is coupling the second leg  512  to the catheter assembly  502  as shown. 
         [0097]    A tube  520  extends from a proximal end portion to a distal end portion of the catheter assembly  502 . The tube  520  is positioned adjacent the outer surface of the stent  504  and graft  514 . The tube  520  is attached to the catheter assembly  502  and not attached to the stent  504  or graft  514 . 
         [0098]    A movable element  522  is threaded through the tube  520  and is circumferentially arranged around the stent  504 . The movable element  522  is looped over release pin  550 , thereby releasably attaching the movable element  522  to the release pin  550 . 
         [0099]    As shown in  FIG. 5B , when tension is applied to the two ends  524  and  526  of the movable element, the movable element  522  radially compresses at least a portion of the stent as previously shown, for example, in  FIG. 2B . When desired, the release pin  550  can be translated in a distal direction as shown by direction arrow  552 , thereby releasing the movable element  522  from the release pin  550  allowing the movable element  522  to be withdrawn. 
         [0100]      FIG. 6A  is a medical apparatus according to an embodiment of the invention.  FIG. 6B  is an enlarged simplified view of a portion of the medical apparatus shown in  FIG. 6A . 
         [0101]    Referring to  FIGS. 6A and 6B , the medical apparatus is generally depicted as reference numeral  600 . The medical apparatus  600  includes a catheter assembly  602 , and stent  604  arranged on the proximal end portion of the catheter assembly  602 . The stent  604  has an inner surface, an outer surface, and is configured from multiple turns of an undulating element  605 . The undulating element  605  may be configured in a ring or helical pattern. 
         [0102]    The stent  604  has a proximal end portion  606  and distal end portion  608 . The distal end portion  608  is formed into a branch having a first leg  610  and a second leg  612 . 
         [0103]    A graft  614  is arranged about the stent  604 . The stent  604  and graft  614  are constrained into a compacted delivery state (or first diameter) by a first sheath  616  and second sheath  618 . As shown in  FIG. 6A , the first sheath  616  has been released allowing at least a portion of the stent  604  to expand as shown. The second sheath  618  is coupling the second leg  612  to the catheter assembly  602  as shown. 
         [0104]    After the release of the first sheath  616 , the stent  604  is allowed to self expand into a second diameter that is greater than the initial compacted first diameter. The second diameter is defined by a secondary constraint  654 . The secondary constraint  654  can be comprised, for example, of a flexible filament that encircles a proximal end portion  606  of the stent and graft. The secondary constraint  654  prevents further self expansion of the stent. 
         [0105]    As shown in  FIG. 6B , the secondary constraint  654  is looped around the stent (not shown) and is threaded through a first end of the secondary constraint  654 . The second end of the secondary constraint  654  is looped onto a release pin  650 . Once the apparatus  600  is properly positioned within a vessel target site, the secondary constraint  654  can be released by translating the release pin  650  in a distal direction as shown by direction arrow  652 . By translating the release pin  650 , the stent is released from the secondary constraint and thereby allowed to further expand into a third diameter that is greater than the second and first diameters. 
         [0106]    Optionally, a retrieval cord or filament  656  can be used to join the secondary constraint  654  to the release pin  650 . Therefore when the release pin is translated distally, the secondary constraint  654  is withdrawn along with the release pin  650 . 
         [0107]      FIG. 7A  is a medical apparatus according to an embodiment of the invention.  FIG. 7B  is an enlarged simplified view of a portion of the medical apparatus shown in  FIG. 7A . 
         [0108]    Referring to  FIGS. 7A and 7B , the medical apparatus is generally depicted as reference numeral  700 . The medical apparatus  700  includes a catheter assembly  702 , and stent  704  arranged on the proximal end portion of the catheter assembly  702 . The stent  704  has an inner surface, an outer surface, and is configured from multiple turns of an undulating element  705 . The undulating element  705  may be configured in a ring or helical pattern. 
         [0109]    The stent  704  has a proximal end portion  706  and distal end portion  708 . The distal end portion  708  is formed into a branch having a first leg  710  and a second leg  712 . 
         [0110]    A graft  714  is arranged about the stent  704 . The stent  704  and graft  714  are constrained into a compacted delivery state (or first diameter) by a first sheath  716  and second sheath  718 . As shown in  FIG. 7A , the first sheath  716  has been released allowing at least a portion of the stent  704  to expand as shown. The second sheath  718  is coupling the second leg  712  to the catheter assembly  702  as shown. 
         [0111]    After the release of the first sheath  716 , the stent  704  is allowed to self expand into a second diameter that is greater than the initial compacted first diameter. The second diameter is defined by a secondary constraint  754 . The secondary constraint  754  is comprised of a flexible band that encircles a proximal end portion  706  of the stent graft. The secondary constraint prevents further self expansion of the stent graft. 
         [0112]    As shown in  FIG. 7B , the secondary constraint  754  is looped around the stent and is threaded through a latch  758  located near a first end of the secondary constraint  754 . A release pin  750  is threaded through the latch  758  to prevent further expansion of the secondary constraint  754 . Once the apparatus  700  is properly positioned within a vessel target site, the secondary constraint  754  can be released by translating the release pin  750  in a distal direction as shown by direction arrow  752 . By translating the release pin  750 , the stent  704  is released from the secondary constraint  754  and thereby allowed to further expand into a third diameter that is greater than the second and first diameters. Optionally, a retrieval cord or filament  756  can be used to join the secondary constraint  754  to the release pin  750 . Therefore when the release pin is translated distally, the secondary constraint  754  is withdrawn along with the release pin  650 . 
         [0113]      FIGS. 8A through 8C  depict a medical apparatus according to an embodiment of the invention. 
         [0114]    Referring to  FIGS. 8A through 8C , the medical apparatus is generally depicted as reference numeral  800 . The medical apparatus  800  includes a catheter assembly  802 , and stent arranged on the proximal end portion of the catheter assembly  802 . As shown in  FIG. 8A  the medical apparatus  800  has a stent constrained into a small delivery diameter  856 . The stent is held in this small delivery diameter by constraining sheaths  850  and  854 . The sheath  850  constrains the trunk of the stent while the sheath  854  constrains the extended leg portion of the stent. A third constraining sheath  852  is contained within the sheath  850 . 
         [0115]    Referring to  FIG. 8B , when the medical apparatus  800  is positioned within a target site, the sheath  850  can be released, allowing at least a portion of the stent to expand to a diameter  858  that is larger than the initial small delivery diameter  856 . The sheath  852  therefore constrains the stent  804  to an intermediate diameter. The sheath  854  constrains the extended leg portion of the stent onto the catheter assembly  802 , thereby allowing the medical apparatus to be repositioned, rotated or precisely aligned to the target site. As shown in  FIG. 8C , when the medical apparatus is precisely positioned, the sheath  852  can be released, allowing the stent to fully expand to a large deployed diameter  860 . The deployed diameter  860  is larger than the intermediate diameter  858 . The intermediate diameter  858  is larger than the delivery diameter  856  as shown in  FIGS. 8A through 8C . Stent anchoring barbs or hooks  862  (when provided) are therefore constrained to the intermediate diameter  858  during final manipulation and positioning of the medical apparatus and allowed to expand and engage a vessel when the constraining sheath  852  is released. 
         [0116]      FIG. 9A  is a partial side view of a medical apparatus  900 , having a constrained medical device  960  located near or at the distal end of a catheter assembly  962 . The catheter assembly  962  has a catheter shaft  964  and a distal guidewire port  966 .  FIG. 9B  is a cross-sectional view of the catheter shaft  964 . Shown contained within the catheter shaft  964  is a guidewire  970 , a release member  972  and an adjustment member  974 . The release member can be a cord, thread, wire, pin, tube or other element used to release a stent (or other medical device) from a constraint, thereby allowing the device to expand from a first compacted delivery profile to a second larger profile. The adjustment member can be a cord, thread, wire, pin, tube or other element used to alter the second profile of at least a portion of the medical device. A catheter used to deliver a medical apparatus can have one, two, three, four or five or more release members combined with one, two, three, four or five or more adjustment members. The release members and adjustment members can be contained in separate or shared lumens within the catheter shaft  964 . 
         [0117]      FIGS. 10A and 10B  show generalized views of a medical apparatus according to an embodiment of the invention (previously described in  FIGS. 2A and 2B ). Shown in  FIG. 10A  is a medical apparatus  1000 , comprised of a stent  1002  having anchor barbs or hooks  1004 . Shown is a tube  1006  having a first movable element  1008  located therein. The first movable element  1008  is shown looped through a second movable element  1010 . As shown in  FIG. 10B , when tension  1012  is applied to the ends of the first movable element  1008 , the second movable element  1010  is drawn into the tube  1006 . When the second movable element  1010  is drawn into the tube  1006 , the stent graft is compressed in the direction indicated by arrows  1014 . The anchors or barbs  1004  are therefore retracted and pulled inwardly away from a vessel wall. The retraction of the anchors or barbs will allow the medical apparatus  1000  to be longitudinally and/or rotationally adjusted. When in the precise target area the tension  1012  on the movable element can be removed, allowing the stent to self expand and engage the anchors or barbs into a vessel wall. 
         [0118]      FIGS. 10C through 10H  show a generalized delivery sequence according to an embodiment of the invention. Shown in  FIG. 10C  is a medical apparatus  1000 , having a first constraining sheath  1020 , a second constraining sheath  1022  and a catheter assembly  1024 . Constrained and contained within the first and second sheaths  1020 ,  1022  is a bifurcated stent having a trunk, a first short leg and a second long leg. As shown in  FIG. 10D , when the medical apparatus is positioned at a target site, the first constraining sheath  1020  is released allowing a portion of the stent and first short leg to self expand. A portion of the stent is held in a constrained small diameter state by movable element  1026 . The movable element  1026  is located in tube  1028 . The stent anchors or barbs  1030  are constrained and pulled inwardly by the movable element  1026 , so that the anchors or barbs do not engage a vessel wall. The second constraining sheath  1022  compresses the stent graft second long leg onto the catheter assembly  1024 . Thus the medical apparatus is captured by the catheter assembly, allowing subsequent repositioning of the medical apparatus. 
         [0119]    As shown in  FIG. 10E , the medical apparatus  1000  can now be readjusted in the longitudinal direction  1032  and/or in the angular direction  1034  through manipulations of the catheter assembly  1024 . 
         [0120]    As shown in  FIG. 10F , when the medical apparatus is precisely positioned, tension on first movable element  1036  is relaxed, allowing second movable element  1038  to expand. As second movable element  1038  expands, the stent is allowed to further expand in the direction  1040 , engaging the anchors or barbs  1030  into a vessel wall. 
         [0121]    As shown in  FIG. 10G , the second constraining sheath  1022  can be released, allowing the second long leg to self expand. 
         [0122]    As shown in  FIG. 10H , one end of first movable element  1036  can be tensioned, allowing first movable element  1036  to be un-looped from second movable element  1038 . First movable element  1036  can then be withdrawn through the tube  1028 . The expanded stent graft is now unattached from the catheter assembly, allowing withdrawal  1042  of the catheter assembly. 
         [0123]    It will be apparent to those skilled in the art that various modifications and variation can be made in the present invention without departing from the spirit or scope of the invention. Thus, it is intended that the present invention cover the modifications and variations of this invention provided they come within the scope of the appended claims and their equivalents.