Abstract:
Delivery systems and methods for delivering modular endovascular graft devices that allow one portion of the repair device to be deployed while maintaining control of the other portions. One system includes an elongate inner member including an anchor stop ring, the anchor stop ring including a plurality of recesses, each sized to receive a portion of the trunk portion and embedding portion of a respective hook in the delivery configuration, each embedding portion extending radially outwardly at an acute angle relative to the trunk portion in the delivery configuration. The delivery systems are simpler to use, easier to manufacture and facilitate better packing of the repair device.

Description:
This application is a continuation of application Ser. No. 10/400,769, filed Mar. 27, 2003 now U.S. Pat. No. 6,984,244. 
    
    
     BACKGROUND OF THE INVENTION 
     This invention relates to systems and methods for delivering and deploying endovascular graft components within the vasculature of a patient. 
     It is well established that various fluid conducting body or corporeal lumens, such as veins and arteries, may deteriorate or suffer trauma so that repair is necessary. For example, various types of aneurysms or other deteriorative diseases may effect the ability of the lumen to conduct fluids and, in turn, may be life threatening. In some cases, the damage to the lumen is repairable only with the use of prosthesis such as an artificial vessel or graft. 
     For repair of vital lumens such as the aorta, surgical repair is significantly life threatening or subject to significant morbidity. Surgical techniques known in the art involve major surgery in which a graft resembling the natural vessel is spliced into the diseased or obstructed section of the natural vessel. Known procedures include surgically removing the damaged or diseased portion of the vessel and inserting an artificial or donor graft portion inserted and stitched to the ends of the vessel which were created by the removal of the diseased portion. More recently, devices have been developed for treating diseased vasculature through intraluminal repair. Rather than removing the diseased portion of the vasculature, the art has taught bypassing the diseased portion with a prosthesis and implanting the prosthesis within the vasculature. An intra arterial prosthesis of this type has two components: a flexible conduit, the graft, and the expandable framework, the stent (or stents). Such a prosthesis is called an endovascular graft. 
     It has been found that many abdominal aortic aneurysms extend to the aortic bifurcation. Accordingly, a majority of cases of endovascular aneurysm repair employ a graft having a bifurcated shape-with a trunk portion and two limbs, each limb extending into separate branches of vasculature. Currently available bifurcated endovascular grafts fall into two categories. One category of grafts are those in which a preformed graft is inserted whole into the arterial system and manipulated into position about the area to be treated. This is a unibody graft. The other category of endovascular grafts are those in which a graft is assembled in-situ from two or more endovascular graft components. This latter endovascular graft is referred to as a modular endovascular graft. Because a modular endovascular graft facilitates greater versatility of matching individual components to the dimensions of the patient&#39;s anatomy, the art has taught the use of modular endovascular grafts in order to minimize difficulties encountered with insertion of the devices into vasculature and sizing to the patient&#39;s vasculature. 
     Although the use of modular endovascular grafts minimize some of the difficulties, there are still drawbacks associated with the current methods of delivering and deploying these grafts. The drawbacks of current methods of delivery and deployment of endovascular graft components include delivery systems that are complicated to use and expensive to manufacture and difficulty in assembling the individual components in-situ. 
     Many delivery systems have three or more catheters coaxially disposed in order to provide adequate control over the endovascular graft and to facilitate inflating an expandable balloon as well as manipulating a release mechanism for deploying the graft. Such systems may be difficult for a single physician to use and, therefore, require additional personnel. The complexity of such delivery systems adds to the difficulty of use as well as the cost of production. 
     A lack of adequate healthy tissue near the aneurysm being treated provides difficulty with adequately anchoring the main body portion of a modular endovascular graft. If the aneurysm extends too close to the bifurcation of the vasculature, there may be a lack of healthy tissue to adequately anchor the limb support branches of the main body component. One method known in the art is to allow the limb support portions of the main body component to float freely in the aneurysm until limb components are delivered and deployed. However, this method presents difficulties with deploying the limb components of the modular endovascular graft within a main body component having limb support portions that are not anchored. 
     In a situation where an endovascular graft configured with superior and inferior anchoring devices is being employed to repair vasculature, it is often desirable to be able to deploy the superior anchoring device prior to deploying the inferior anchoring device. It is also often desirable to minimize the interference between the inferior anchoring device and other components of a delivery system. Although there has been some success in this area, there is nevertheless a need for a mechanism which effectively and consistently accomplishes these goals. 
     With regard to the method of delivery and deployment of endovascular graft components, there therefore exists a need for a endovascular graft delivery system that limits the number of components which must be manipulated, can be easily operated by a single technician without decreased reliability or additional risk to the patient, and facilitates control of graft deployment as well as control of a previously deployed main body component in order to deliver and deploy limb components therein. The devices and methods of the present invention addresses these and other needs. 
     SUMMARY OF THE INVENTION 
     Briefly and in general terms, the present invention is embodied in delivery systems and methods for delivering and deploying a medical repair device in vasculature. The delivery systems and methods minimize redundancy and are relatively easy to operate or perform as well as allowing increased control over a partially deployed component. 
     Throughout this specification, the term “proximal” shall mean “nearest to the heart,” and the term “distal” shall mean “furthest from the heart.” Additionally, the term “ipsi-lateral” shall mean the limb of a bifurcated graft which is deployed using the same path through the vasculature that was used to deploy the main body component, and the term “contra-lateral” shall mean the limb of a bifurcated graft which is deployed using a second path through the vasculature which is catheterized after the main body component has been deployed. Furthermore, the term “inferior” shall mean “nearest the technician”, and the term “superior” shall mean “farthest from the technician.” 
     In one aspect of the invention, a system for delivering a medical repair device to a repair site is provided that facilitates controlled deployment of the repair device. The system consists of a sheath coaxially disposed over two elongate members and the repair device. One member is at least partially coaxially disposed over the other member such that the inner member may slide longitudinally relative to the outer member. The repair device has a proximal portion and a distal portion, each portion releasably secured to one of the members such that relative longitudinal movement between the sheath and the two members allows the repair device to be deployed one portion at a time. When used with a bifurcated graft component having a proximal portion and two distal portions, the delivery system allows the proximal portion to be deployed and secured within the vasculature and one distal portion to be deployed and accessed from the contra-lateral side while the other distal portion is held taut. 
     The inner member provides a guidewire lumen for the delivery system. An inflatable balloon may be provided at the superior end of the inner member with an inflation lumen facilitating inflation and deflation of the balloon via an inlet port at the inferior end. In one embodiment, the balloon is located under the repair device. 
     The repair device may be secured to the inner member by a release wire with a release wire lumen facilitating deployment of the repair device via an inlet port at the inferior end. In one embodiment, the inner member has a triple lumen with three inlet ports at the inferior end, the inlet ports providing guidewire access, an inflation lumen, and a release wire lumen. 
     The inferior end of the outer member facilitates locking the two members together, for example with a locking mechanism, thereby precluding relative movement. The superior end of the outer member facilitates releasably securing one portion of the repair device, for example with an area of raised diameter that pinches the repair device against the sheath. In one embodiment, a valve assembly with a locking mechanism is provided at the inferior end of the outer member, the locking mechanism securing the inner member to the outer member, and an inlet port in the valve assembly allows the space between the inner and outer members to be cleared by flushing with a liquid. 
     The repair device may have anchoring mechanisms at the proximal and distal ends and hooks to facilitate embedding the device in vasculature. The anchoring mechanisms may be self-expanding or balloon-expandable. It is contemplated that the delivery system may be used with any graft component known in the art. 
     In another aspect of the invention, a system for delivering a medical repair device is provided that isolates an anchoring device of the repair device from the sheath. In-one embodiment, the delivery system is configured with a hook capsule and an anchor stop ring which cooperate to both isolate an anchoring device as well as effectively enable the deployment of a proximal portion of the repair device prior to a distal portion thereof. 
     In yet another aspect of the invention, methods are provided for delivering the individual components of a modular medical repair device and assembling the components in-vivo. For example, the main body component of a modular endovascular graft prosthesis, having an attachment stent with hooks at the proximal end, may be delivered and deployed utilizing one delivery system of the present invention and the limb components of the modular endovascular graft prosthesis may be delivered and deployed utilizing another delivery system of the invention. 
     The trunk portion and the contra-lateral leg portion of the main body component are secured between the inner member and the sheath of the main body component delivery system and the ipsi-lateral leg portion is secured between the outer member and sheath. Once the delivery system is advanced to the treatment site, the sheath is retracted to deploy only the trunk portion and the contra-lateral leg portion. If a release wire is used to secure the trunk portion and/or contra-lateral leg portion of the main body component to the inner catheter, a release wire lumen in the inner member facilitates deployment. 
     An inflation balloon may be provided on the inner member and an inflation lumen utilized to embed the attachment hooks at the proximal end of the main body component in the vasculature. Relative longitudinal movement between the outer and inner members allows the inflatable balloon to be positioned with respect to the main body component. 
     Once the proximal end of the main body component is embedded in the vasculature, a limb component is delivered through the contra-lateral branch of the vessel using a limb component delivery system and attached to the contra-lateral leg portion of the main body component. The main body delivery system of the present invention facilitates holding the undeployed ipsi-lateral leg portion of the main body component taut, thereby making the contra-lateral deployment procedure easier. 
     Once the contra-lateral limb is attached to the main body component, the sheath of the main body component delivery system is retracted further to deploy the ipsi-lateral leg portion. An ipsi-lateral limb component is then delivered and attached to the ipsi-lateral leg portion. 
     Other features and advantages of the present invention will become apparent from the following detailed description taken in conjunction with the accompanying drawings, which illustrate, by way of example, the principles of the invention. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a perspective view of a delivery system of the present invention with the sheath retracted; 
         FIG. 2  is a partial cross-sectional view of the superior end of the delivery system of  FIG. 1 ; 
         FIG. 3  is a cross-sectional view across line  3 - 3  of  FIG. 2 ; 
         FIG. 4  is a partially fragmented perspective view of an alternate embodiment of a delivery system of the present invention with the sheath retracted; 
         FIG. 5  is a partial perspective view of the superior end of the delivery system of  FIG. 4  without the repair device; 
         FIG. 6  is a partial perspective view of the superior end of the delivery system of  FIG. 4  showing the proximal portion of the repair device; 
         FIG. 7  is a schematic view of a main body component of a modular bifurcated graft prosthesis of the type that may be delivered using the delivery system of  FIG. 4 ; 
         FIG. 8  is a partial cross-sectional view depicting a delivery system of the present invention inserted in the vasculature of a patient with the sheath retracted to expose the trunk portion of a bifurcated endovascular graft component; 
         FIG. 9  is a partial cross-sectional view depicting a delivery system of the present invention inserted in the vasculature of a patient with the trunk portion and contra-lateral limb portion of a bifurcated endovascular graft component deployed and the ipsi-lateral limb portion held taut by the delivery system; 
         FIG. 10  is a partial cross-sectional view depicting a delivery system of the present invention inserted in the vasculature of a patient with the trunk portion and contra-lateral limb portion of a bifurcated endovascular graft component deployed and a contra-lateral limb component attached to the contra-lateral limb portion while the ipsi-lateral limb portion is held taut by the delivery system; 
         FIG. 11  is a partial cross-sectional view depicting a delivery system of the present invention inserted in the vasculature of a patient with the sheath retracted to deploy the ipsi-lateral limb portion of a bifurcated endovascular graft component; 
         FIG. 12  is a perspective view of an alternate embodiment of a delivery system of the present invention with the sheath retracted; 
         FIG. 13  is a fragmented sectional side view of the delivery system of  FIG. 12  with the hook capsule retracted to expose the inferior stop ring; 
         FIG. 14  is a cross-sectional view across line  14 - 14  in  FIG. 13 ; 
         FIG. 15  is a fragmented sectional side view of the delivery system of  FIG. 12  with the hook capsule covering the inferior stop ring; 
         FIG. 16  is a schematic view of a limb component of a modular bifurcated graft prosthesis of the type that may be delivered using the delivery system of  FIG. 12 ; 
         FIG. 17  is a perspective view of an iliac attachment system with “cross”-like hooks; and 
         FIG. 18 . is a perspective view of the superior end of the delivery system of  FIG. 12  with the hook capsule retracted to expose the cross-like hooks of an iliac attachment system held in the inferior stop ring. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     The present invention relates to systems and methods for accurately delivering and deploying medical repair devices at a treatment site within a patient&#39;s vasculature. 
     Referring to  FIG. 1 , an embodiment of a main body delivery system  10  of the present invention is shown. The delivery system  10  is defined by an inferior end  12  and a superior end  14  and has three main sections; the inner catheter  20 , the main catheter  30  and sheath assembly  40 . 
     The elongate inner catheter  20  is generally tubular and defined by an inferior end  22  and superior end  24 . The inner catheter  20  extends almost the entire length of the delivery system  10  from the inferior end  12  to the superior end  14 . The inner catheter  20  provides the lumen for a guidewire (not shown) over which the delivery system  10  is inserted into a body lumen. 
     The elongate main catheter  30  is generally tubular and defined by an inferior end  32  and superior end  34 . The main catheter  30  is at least partially coaxially and slidably disposed over the inner catheter  20  such the inner catheter may slide longitudinally relative to the main catheter. A balloon lock mechanism  60  at the inferior end  32  of the main catheter  30  facilitates releasably locking the inner catheter  20  to the main catheter, thereby precluding relative movement. 
     The sheath assembly  40  is defined by an inferior end  42  and superior end  44  and is coaxially and slidably disposed over the portion of the inner catheter  20  and main catheter  30  to which a medical repair device  90  such as an endovascular graft component (indicated by the dotted line in  FIG. 1 ) is releasably secured. A jacket lock mechanism  80  at the inferior end  42  of the sheath assembly  40  facilitates retracting the sheath distally, advancing the sheath proximally and releasably locking the sheath in its retracted or advanced position. 
     The superior end  24  of the inner catheter  20  may have an inflatable balloon  100  to facilitate expanding the repair device  90  after it has been deployed in the vasculature of a patient. A jacket guard  130  is provided at the superior end  24  of the inner catheter  20 . A superior capsule  1300  is provided at the superior end  44  of the sheath assembly  40  to isolate the sheath assembly  40  from a superior anchor frame  96  at the proximal portion  92  of the repair device  90  (see  FIG. 2 ). The jacket guard  130  is designed to receive the jacket capsule  1300  at the most proximal position of the sheath assembly  40 . A nose cone  50  is attached to the distal end  24  of the inner catheter  20 , the resulting smooth profile of the delivery system  10  facilitating easier maneuverability through a patient&#39;s vasculature. The jacket guard  130  and nose cone  50  may be made of radiopaque material or have radiopaque markers to facilitate positioning the main body delivery system  10  in the vasculature under fluoroscopy. 
     If an inflatable balloon  100  is provided, the inner catheter  20  will have an inflation lumen  101  therethrough (see  FIG. 3 ). Furthermore, it is contemplated that the repair device  90  may be secured to the inner catheter  20  utilizing a release wire  98  (see  FIG. 2 ) with a release wire lumen  103  provided through the inner catheter  20  (See  FIG. 3 ). A port  110  at the inferior end  22  of the inner catheter  20  provides an exit point  112  for a guidewire (see  FIG. 1 ) and an exit point  114  for the release wire  98  as well as access  116  for inflating and deflating the inflatable balloon  100 . The port  110  has a guidewire inlet  112 , inflation inlet  116 , and release wire inlet  114  and also serves as a handle for retracting the inner catheter  20  distally or advancing the inner catheter proximally. 
     In a preferred embodiment, the inner catheter  20  consists of a Pebax nose cone  50  affixed to a hypotube, a tri-lumen coaxially affixed over the hypotube, and an SST tube covering the distal end  22 . The hypotube provides the guide wire lumen and serves as the backbone of the inner catheter  20 . The tri-lumen coaxially provides a hypo-tube lumen  21 , the release wire lumen  103  and the inflation lumen  101  for the expandable balloon  100 , which is mounted thereon (see  FIGS. 2 and 3 ). The SST tube covers approximately the last twelve inches of the inferior end  22  of the inner catheter  20 . The hypotube, tri-lumen and SST tube are fixed together by the port  110 . 
     The main catheter  30  has a localized sharp rise in diameter  70  at the superior end  34  that facilitates holding a distal end portion of a repair device  90  such as an endovascular graft component, though the structure can be employed to receive any portion of a medical device (See  FIG. 4 ). It is contemplated that the localized sharp rise in diameter  70  may be formed as part of the main catheter  30  or may consist of, for example, a sleeve that is added after manufacture. The localized sharp rise in diameter  70  can be made of any biocompatible material that accomplishes holding a portion of a repair device  90  against the inside surface of the sheath assembly  40  and is particularly useful when the repair device is a bifurcated graft component. A valve assembly  120  at the inferior end  32  of the main catheter  30  facilitates flushing out air from the annular space  111  (see  FIG. 3 ) between the inner catheter  20  and main catheter  30 . In a preferred embodiment, the main catheter  30  consists of a Pebax shaft. 
     Referring to  FIG. 2 , one embodiment of the superior end  14  of the delivery system  10  is illustrated. The repair device  90  has a proximal portion  92  and a distal portion  94 . A superior anchor frame  96  containing attachment hooks is provided at the proximal portion  92  of the repair device  90  to facilitate imbedding the repair device in a body lumen. The superior capsule  1300  isolates the attachment hooks from the sheath assembly  40 , thereby preventing the hooks from interfering with retraction of the sheath assembly. A release wire  98  cooperates with a securing mechanism  99 , for example suture loops held together by the release wire, to secure the proximal portion  92  and superior anchor frame  96  of the repair device  90  to the inner catheter  20 . The distal portion  94  of the repair device  90  is secured between the localized sharp rise in diameter  70  at the superior end  34  of the main catheter  30  and the sheath assembly  40 . 
     Referring to  FIG. 3  with continued reference to  FIGS. 1 and 2 , the tri-lumen of the inner catheter  20  is illustrated. The guide wire/hypo-tube lumen  21  extends throughout the length of the inner catheter  20  and is in fluid communication with the guidewire inlet  112  in the port  110  at the inferior end  22  of the inner catheter  20 . The guide wire/hypo-tube lumen  21  facilitates passing a guide wire (not shown) through the delivery system  10 : The inflation lumen  101  is in fluid communication with and connects the inflation inlet  116  in the port  110  at the inferior end  22  of the inner catheter  20  to an injection orifice  102  under the inflatable balloon  100 . The inflation lumen  101  facilitates inflating and deflating the inflatable balloon  100  during delivery of the endovascular graft  90 . The release wire lumen  103  is in fluid communication with and connects the release wire inlet  114  in the port  110  at the inferior end  22  of the inner catheter  20  to a release wire orifice  1400  near the proximal portion  92  of the repair device  90 . The proximal end of the release wire  98  is secured inside the wire orifice  104  on the capsule guard  130 . The release wire lumen  103  facilitates deploying the proximal portion  92  of the repair device  90 . 
     In operation, the delivery system  10  facilitates deploying the proximal portion  92  of the repair device  90  while maintaining control of the distal portion  94  of the repair device. When the sheath assembly  40  is retracted such that the proximal portion  92  of the repair device  90  is exposed but the superior end  44  of the sheath assembly  40  is proximal the localized sharp rise in diameter  70  at the superior end  34  of the main catheter  30 , the distal portion  94  of the repair device is still held between the sheath assembly and localized sharp rise in diameter. As long as the sheath assembly  40  is not retracted further, the distal portion  94  of the repair device  90  will not deploy. The jacket lock mechanism  80  at the inferior end  42  of the sheath assembly  40  facilitates locking the sheath in its partially-retracted position. 
     When the release wire  98  is retracted through the release wire lumen  103  by pulling it distally from the release wire inlet  114  in the port  110 , the securing mechanism  99  is released and the proximal portion  92  of the repair device  90  is deployed, the hooks of the superior anchor frame  96  embedded in the lumen wall either by self-expanding or by moving the inner catheter  20  distally and inflating the balloon  100  via the inflation lumen  101 . The balloon lock mechanism  60  at the inferior end  32  of the main catheter  30  facilitates unlocking the inner catheter  20  from the main catheter so that the inner catheter and the attached balloon  100  may be moved distally until the balloon is inside the proximal portion  92  of the repair device  90 . 
     If, for example, the repair device  90  is the main body component of a modular bifurcated prosthesis, the trunk portion and contra-lateral limb portion may be releasably secured to the inner catheter  20  by the release wire  98  and the ipsi-lateral limb portion may be held between the localized sharp rise in diameter  70  at the superior end  34  of the outer catheter  30  and the sheath assembly  40 . The delivery system  10  facilitates deploying the trunk portion and contra-lateral limb portion of the main body component  90  while maintaining control of the ipsi-lateral limb portion. In this manner, accessing and deploying a limb component inside the contra-lateral limb portion of the main body component  90  is simplified since the physician may hold the ipsi-lateral limb portion taut while the contra-lateral side is accessed. It is contemplated that the delivery system  10  of the present invention may be utilized whenever it is desired to deploy one portion of a repair device  90  while maintaining control over the other portions. 
     Referring to  FIG. 4 , an alternate embodiment of a main body delivery system  210  of the present invention is shown. The delivery system  210  is similar to that illustrated in  FIG. 1  and further includes a stopper  281 , an aortic frame stop ring  270  and a superior capsule  241 , and the inflatable balloon  260  is located underneath the repair device  90 . 
     The stopper  281 , which can be manipulated to releasably attach to the main catheter  30 , provides a safeguard against retracting the sheath assembly  240  too far during the various stages of deploying a repair device  90 , for example the main body component of a modular bifurcated prosthesis (see  FIGS. 8-11 ). When the stopper  281  is attached to the main catheter  30 , the sheath assembly  240  cannot be retracted past the stopper  281  even if the jacket lock mechanism  280  is unlocked. It is contemplated that the superior end  282  of the stopper  281  and inferior end  283  of the jacket lock mechanism  280  may contain a mechanism (not shown) for releasably attaching the jacket lock mechanism to the stopper, thereby allowing them to be retracted as a single unit. With the stopper  281  inhibiting retraction of the sheath assembly  240 , the physician can more efficiently manipulate the delivery system  210  since he does not have to monitor the longitudinal position of the jacket lock mechanism  280  with respect to the main catheter  30 , thereby allowing him to concentrate on the deployment process under fluoroscopy. 
     In operation, the stopper  281  may be tightened at a location along the main catheter  30  such that when the sheath assembly  240  is retracted until it contacts the stopper  281 , the proximal portion  92  of the repair device  90  is exposed but the superior end  244  of the sheath assembly  240  is proximal the localized sharp rise in diameter  70  at the superior end  34  of the main catheter  30 , thereby holding the distal portion  94  of the repair device between the sheath assembly and localized sharp rise in diameter. When it is desired to deploy the distal portion  94  of the repair device  90 , the stopper  281  is released from the main catheter  30 , thereby allowing the stopper  281  and jacket lock mechanism  280  to be retracted such that the superior end  244  of the sheath assembly  240  is distal the localized sharp rise in diameter  70  at the superior end  34  of the main catheter. 
     The aortic frame stop ring  270  is attached near the superior end  24  of the inner catheter  20  just proximal the inflatable balloon  260 . A jacket guard  230  is located at the superior end of the inner catheter  20  just distal the nose cone  250 . Both may be made of radiopaque material. The aortic frame stop ring  270  isolates the superior anchor frame  96  from the rest of the proximal portion  92  of a repair device  90  (see  FIG. 6 ) and may provide a marker by which the distal end of the superior anchor frame can be located during operation under fluoroscopy, thereby facilitating precise deployment. A superior capsule  241  attached to the superior end  244  of the sheath assembly  240  covers the superior anchor frame  96  when the sheath assembly is advanced proximally, thereby preventing the hooks of the superior anchor frame from tearing the sheath assembly. 
     As illustrated in  FIGS. 5 and 6 , the bare hypotube of the inner catheter  20  between the aortic frame stop ring  270  and jacket guard  230  provides a space for the superior anchor frame  96  of the repair device  90 . The release wire  298  is routed through the release wire lumen  103  and terminates in the jacket guard  230 . 
     In operation, the sheath assembly  240  is retracted such that the superior capsule  241  is distal the superior anchor frame  96 . The proximal portion  92  of the repair device  90  and superior anchor frame  96  may then be deployed by pulling the release wire  298  distally from the release wire inlet  114  in port  110 . 
     Referring to  FIG. 7 , a typical main body component  190  of a modular bifurcated endovascular graft prosthesis of the type used in the system of  FIG. 4  is shown. The main body component  190  includes a trunk portion  192  and two limb portions  194 ,  195 . The main body component  190  is preferably made of a woven Polyethylene Terephthalate (PET) material. 
     An aortic attachment system  196 , having hooks for imbedding in the vasculature of a patient, is provided at the proximal end of the trunk portion  192 . Radiopaque markers  197  along the trunk  192  portion, at the crotch and at the distal end of the limb portions  194 ,  195  facilitate visualization under fluoroscopy. Self-expanding port stents  198 , preferably made of Nitinol, at the distal end of the limb portions  194 ,  195  provide patency for cannulation and consistent interface when attaching a limb component (see  FIG. 16 ) to the main body component  190 . Fuzzy tufts of yarn  199  on the trunk portion  192  just distal the aortic attachment system  196  facilitate better attachment in the vasculature of a patient. The limb portions  194 ,  195  may be secured to each other by sutures  200  or other means to facilitate better control during deployment of the limb portions during in situ assembly. 
     Note that the main body component  190  has no stent structure or support between the aortic attachment system  196  and port stents  198  at the distal end of the limb portions  194 ,  195 . This area, consisting only of graft material, facilitates placing the inflatable balloon  260  under the main body component  190  while still maintaining a small delivery profile. 
     The inflatable balloon  260  is preferably made of a PET material although other materials such as polyurethane are contemplated. It is contemplated that a balloon  260  with an inflation diameter of 24 mm, 26 mm or 28 mm may be packed to a profile of 0.166″ and a balloon with an inflation diameter of 30 mm or 32 mm may be packed to a profile of 0.186″. With the balloon  260  located under the repair device  90 , the delivery system  210  is easier to use since the packed inflatable balloon adds no additional diameter to the delivery system  210  distal the superior anchor frame  96 . The balloon  260  can be made of Pellethane 2363-65D which is a thermoplastic polyurethane elastomer made up of diisocyanate and diol hard segment and polyether soft segment with durometer hardness of 62, flexural modulus of 32,000 psi, tear strength of 1100 Pli and elongation at break elasticity of 450%. The balloon operates 0.5 to 5 atmospheres in a balloon outer diameter range from 12 to 32 mm. This material has unique properties including semi-compliant and compliant distension attributes, excellent flexibility, low profile, good refold and fast inflation and deflation times. 
     Referring to  FIGS. 8-11 , a method of utilizing the main body delivery system  210  of the present invention to deploy the main body component  190  illustrated in  FIG. 7  and assemble a modular bifurcated prosthesis in situ is illustrated. The repair device  190  is the main body component of the modular bifurcated prosthesis. The main body component  190  is packed in the delivery system  210  with the inner catheter  20  inside the trunk portion  192  and ipsi-lateral limb portion  194  while the contra-lateral limb portion  195  is folded back and over the ipsi-lateral limb portion  194 . The trunk portion  192  is releasably secured to the inner catheter  20  by a graft securing mechanism  99  in cooperation with the release wire  298 . The ipsi-lateral limb portion  194  is secured between the sheath assembly  240  and localized sharp rise in diameter  70  at the superior end  34  of the outer catheter  30 . 
     The main body delivery system  210 , having the inner catheter  20  locked to the main catheter  30  with the sheath assembly  240  advanced over the main body component  190  and locked in place, is advanced over a guide wire (not shown) through the ipsi-lateral branch  154  of the patient&#39;s vasculature  150 . The main body delivery system  210  is advanced until the trunk portion  192  of the main body component  190  is located just proximal of the aneurysm  152 . The sheath assembly  240  is then released via the jacket lock mechanism  280  and retracted until the superior end  244  of the jacket assembly is distal the trunk portion  192 , as shown in  FIG. 8 . The sheath assembly  240  is then retracted further until the superior end  244  of the jacket assembly is distal the contra-lateral limb portion  194  of the main body component  190  but proximal the localized sharp rise in diameter  70  at the superior end  34  of the outer catheter  30 . The sheath assembly  240  is then locked in the partially-retracted position via the jacket lock mechanism  280 . In this configuration of the delivery system  210 , the trunk portion  192  and contra-lateral limb portion  195  of the main body component  190  are exposed. In this configuration the trunk portion  192  of the body component  190  is still retained to the inner catheter  20  by the graft securing mechanism  99  and release wire  298 . 
     Next, as shown in  FIG. 9 , the release wire  298  is retracted, releasing the graft securing mechanism  99  and allowing the trunk portion  192  of the main body component  190  to deploy. The inner catheter  20  is then unlocked from the main catheter  30  via the balloon lock mechanism  60  and advanced proximally, while the main catheter  30  and sheath assembly  240  are held stationary, until the inflatable balloon  260  is located inside the anchor frame  96  of the main body component  190 . The inflatable balloon  260  is inflated and deflated to embed the hooks of the aortic attachment system  196  in the lumen  150  proximal the aneurysm  152 . 
     Next, as shown in  FIG. 10 , the inner catheter  20  is advanced proximally until the balloon  260  is proximal the deployed trunk portion  192  of the main body component  190  and the inner catheter  20  is then locked to the main catheter  30  via the balloon lock mechanism  60 . With the delivery system  210  holding the ipsi-lateral limb portion  194 , the contra-lateral branch  153  of the patient&#39;s vasculature  150  is then accessed by a method known in the art and a limb component  160  is attached to the contra-lateral limb portion  195  of the main body component  190 . 
     Finally, as shown in  FIG. 11 , the sheath assembly  240  is released via the jacket lock mechanism  280  and retracted until the superior end  244  of the sheath assembly is distal the localized sharp rise in diameter  70  at the superior end  34  of the outer catheter  30 , thereby allowing the ipsi-lateral limb portion  194  to deploy. The main body delivery system  210  may then be removed from the patient&#39;s vasculature  150  and a limb component (not shown) attached to the ipsi-lateral limb portion  194  of the main body component  190  using a method known in the art. 
     Although  FIGS. 8-11  illustrate the delivery of a main body component  190  of a modular bifurcated prosthesis, it is contemplated that the delivery system  210  may be utilized any time it is desired to deploy a portion of a medical repair device  90  while maintaining control of the other portions. It is also contemplated that the main body delivery system  210  may be used with a medical repair device  90  which is self-expanding without a balloon  100  provided. 
     The main body delivery systems,  10 ,  210  of the present invention are simpler to use and cheaper to build because they have less components and are easier to assemble and manufacture. Furthermore, the endovascular graft component  90  is easier to pack and it is contemplated that various graft thicknesses from 0.0045″ to 0.0065″ may be used. 
     Referring to  FIG. 12 , an embodiment of a limb delivery system  310  of the present invention is shown. The delivery system  310  is defined by an inferior end  312  and a superior end  314  and has three main sections; the inner catheter  320 , the main catheter  330  and sheath assembly  340 . 
     The elongate main catheter  330  is generally tubular and defined by an inferior end  332  and superior end  334  and is at least partially coaxially and slidably disposed over the inner catheter  320  such that the inner catheter may slide longitudinally relative to the main catheter. A distal capsule lock mechanism  360  at the inferior end  332  of the main catheter  330  facilitates releasably locking the inner catheter  320  to the main catheter, thereby precluding relative movement. The distal capsule lock mechanism  360  also serves as a handle for retracting the main catheter  330  distally or advancing the main catheter proximally. 
     A capsule  333  at the superior end  334  of the main catheter  330  is sized and dimensioned to receive the distal portion  394  of a medical repair device  390  such as an iliac attachment system  398  of an endovascular graft limb component (see  FIG. 16 ), though the structure can be employed to receive any portion of a repair device. The capsule  333 , which may be moved relative to the inner catheter  320 , cooperates with the inner catheter to gain control of the distal portion  394  of a repair device  390 . The capsule  333  can be made of any biocompatible material that accomplishes isolating the repair device  390  from the sheath assembly  340  and is particularly useful when the repair device includes hooks or barbs  410  designed to aid in implanting the device within vasculature. The capsule  333  may be made of radiopaque material or have radiopaque markers to facilitate tracking the relative position of the capsule and inner catheter  320 . 
     The elongate inner catheter  320  is generally tubular and defined by an inferior end  322  and superior end  324  and extends almost the entire length of the delivery system  310  from the inferior end  312  to the superior end  314 . The inner catheter  320  provides the lumen for a guidewire (not shown) over which the delivery system  310  is inserted into a body lumen. A nose cone  350  is attached to the distal end  324  of the inner catheter  320 , the resulting smooth profile of the delivery system  310  facilitating easier maneuverability through a patient&#39;s vasculature. 
     The inner catheter  320  further includes a jacket guard  331  at the superior end  324  just distal the nose cone  350 , a superior stop ring  370  affixed near the superior end distal the jacket guard, an inferior stop ring  321  affixed distal the superior stop ring, and a knob  326  at the inferior end  322 . The jacket guard  331 , superior stop ring  370 , inferior stop ring  321  and nose cone  350  may be made of radiopaque material or have radiopaque markers to facilitate positioning the limb delivery system  310  in the vasculature of a patient. 
     The jacket guard  331  is similar to the jacket guard  230  illustrated in  FIG. 4 . The jacket guard  331  may provide a marker by which the proximal portion  392  of the repair device  390  can be located during operation under fluoroscopy. The superior stop ring  370  is similar to the aortic frame stop ring  270  illustrated in  FIG. 4 . The superior stop ring  370  isolates the proximal lock stent  396  from the rest of the proximal portion  392  of a repair device  390  and may provide an additional marker by which the proximal lock stent  396  of the repair device  390  can be located during operation under fluoroscopy. 
     The inferior stop ring  321  is attached to the inner catheter  320  such that its position is fixed relative to the nose cone  350 . The stop ring  321  is sized and dimensioned to receive the distal portion  394  of a repair device  390  such as an iliac attachment system  398  of an endovascular graft limb component (see  FIG. 16 ), though the structure can be employed to receive any portion of a medical repair device. The inferior stop ring  321  cooperates with the capsule  333  of the main catheter  330  to gain control of a distal portion  394  of a repair device  390 . The inferior stop ring  321  can be made of any biocompatible material that accomplishes holding a portion of a repair device  390  in cooperation with the capsule  333  of the main catheter  330  and is particularly useful when the repair device includes hooks or barbs designed to aid in implanting the device within vasculature. 
     The knob  326  facilitates relative movement between the inner catheter  320  and outer catheter  330 . When the distal capsule lock mechanism  360  of the main catheter  330  is unlocked, the knob  326  may be held while retracting the main catheter  330  distally, thereby exposing the inferior stop ring  321  of the inner catheter and allowing the distal portion  394  of a repair device  390  to deploy. 
     The sheath assembly  340  is defined by an inferior end  342  and superior end  344  and is coaxially and slidably disposed over the portion of the inner catheter  320  and main catheter  330  to which a repair device  390  is releasably secured. A jacket lock mechanism  380  at the inferior end  342  of the sheath assembly  340  facilitates retracting the sheath distally, advancing the sheath proximally and releasably locking the sheath in its retracted or advanced position. A valve assembly  311  facilitates flushing out air from the annular space between the outer catheter  330  and sheath assembly  340 . The distal end  344  of the sheath assembly  340  has a radiopaque marker band  346  to facilitate positioning the repair device  390  in the vasculature of a patient utilizing fluoroscopy. 
     Referring to  FIG. 13 , one embodiment of the inferior stop ring  321  includes an inferior end portion configured with a cap  371  having a rounded inferior surface  372  and a substantially flat superior surface  373  as well as a superior end portion with a knob  375  having grooves  376  arranged to receive a radial dimension of struts of the distal portion  394  of a repair device  390 , for example an iliac attachment system  398 . The midsection  377  of the inferior stop ring  321  can be tapered to define a space for receiving a longitudinal dimension of an iliac attachment system  398 . As can best be seen in  FIG. 14 , the grooves  376  are preferably located at equidistant points about the circumference of the knob  375 . Although  FIG. 13  depicts one embodiment of the inferior stop ring  321 , it is to be understood that various other embodiments are contemplated, each of which can include specific structure for receiving and retaining the distal portion  394  of a repair device  390 . The knob  375  may also have a rounder inferior surface like surface  372  of cap  371 . 
     As shown in  FIG. 15 , when the distal capsule lock mechanism  360  is advanced proximally such a gap exists between the lock mechanism and the knob  326  at the inferior end  322  of the inner catheter  320 , the capsule  333  of the main catheter  330  covers the inferior stop ring  321 . In operation, a distal portion  394  of a repair device  390  placed over the inferior stent stop ring  321  will be pressed against the stop ring by the capsule  333 , thereby restraining it and preventing it from deploying. If the distal portion  394  of the repair device  390  is an iliac attachment system  398  of an endovascular graft limb component, the hooks will be pressed into the grooves  376  of the stop ring  321  and prevented from contacting the sheath assembly  340 . 
     Referring again to  FIG. 13 , when the distal capsule lock mechanism  360  is retracted distally such that little or no gap exists between the lock mechanism and the knob  326  at the inferior end  322  of the inner catheter  320 , the capsule  333  of the main catheter  330  is distal the inferior stop ring  321 , no longer pressing the distal portion  394  of the repair device  390  against the stop ring. If the sheath assembly  340  has been retracted such that the superior end  344  is distal the stop ring  321 , the distal portion  394  of the repair device  390  is allowed to deploy. If the distal portion  394  of the repair device  390  is an iliac attachment system  398  of an endovascular graft limb component, the hooks will be free to imbed in the vasculature of a patient or in another endovascular graft component into which the delivery system  310  has been inserted. 
     Referring to  FIG. 16 , an endovascular graft limb component  390  of the type deliverable with the delivery system  310  is shown. The limb component  390  is defined by a proximal portion  392  and a distal portion  394 . The limb component preferably is made of a woven PET material. 
     A self-expanding lock stent  396  is provided at the proximal portion  392  of the limb component  390 . The lock stent  396  has hooks  400  that protrude through the graft material for locking the limb component  390  to a limb portion  194 ,  195  of a main body component  190  (see  FIG. 7 ) of an endovascular prosthesis. A self-expanding iliac attachment system  398 , having hooks  410  for imbedding in the vasculature of a patient to fix the implant to the artery wall, is provided at the distal portion  394  of the limb component  390 . Radiopaque markers  397  along the limb component  390  facilitate accurate deployment under fluoroscopy. Fuzzy tufts of yarn  399  near the distal portion  394  facilitate better attachment in the vasculature of a patient. 
     The hooks  410  of the iliac attachment system  398  protrude from the distal portion  394  of the limb component  390  and preferably are made of Nitinol. As shown in  FIG. 17 , the hooks  410  have a profile that resembles a cross. It is contemplated that the cross may have one or more arms  411  that are essentially perpendicular to the trunk  412  of the hook  410 . 
     As shown in  FIG. 18 , when the limb component  390  is mounted in the delivery system  310 , the trunk  412  of the hook  410  sits in a groove  376  of the inferior stop ring  321  and the arms  411  of the hook rest distal to the groove. When the capsule  333  of the main catheter  330  covers the inferior stop ring  321 , the arms  411  of each hook  410  are effectively captured between the capsule and the stop ring. 
     It will be apparent that, when the distal capsule lock mechanism  360  is retracted to remove the capsule  333  of the main catheter  330  from the inferior stop ring  321  before the sheath assembly  340  is retracted, the hooks  410  of the iliac attachment system  398  would prevent the sheath assembly from being retracted. The movement of the inner catheter  320  relative to the main catheter  330  may, therefore, be limited by the design as a safety precaution. Such a precaution can be making the spacing between the distal capsule lock mechanism  360  and knob  326  shorter than the spacing between the proximal end  344  of the sheath assembly  340  and the hooks  400  of the limb component. This design limitation ensures that in the event of reverse-order deployment or misuse, the hooks  400 ,  410  of the lock stent  396  and the iliac attachment system  398 , respectively, will remain inside the delivery system  310 , thereby allowing the delivery system to be removed from the patient without further damage to the vasculature. 
     In use, the delivery system  310  is loaded with a repair device  390 , such as the endovascular graft limb component shown in  FIG. 16 . The repair device  390  is loaded such that the lock stent  396  rests in the space between the superior stop ring  370  and jacket guard  331  and the hooks  410  of the iliac attachment system  398  rest against the inferior stop ring  321  as shown in  FIG. 18 . The main catheter  330  is advanced proximally as shown in  FIG. 15  and locked to the inner catheter  320  using the distal capsule lock mechanism  360  such that the capsule  333  of the main catheter covers the inferior stop ring  321 , thereby pressing the hooks  410  of the iliac attachment system  398  against the inferior stop ring. The sheath assembly  340  is advanced and locked using the jacket lock mechanism  380  such that the sheath assembly covers the repair device  390 , its superior end  344  forming a smooth transition with the nosecone  350 . 
     The delivery system  310  is advanced through vasculature to a repair site. The jacket lock mechanism  380  is unlocked and the sheath assembly  340  is retracted to allow deployment of the lock stent  396  of the repair device  390  while the hooks  410  of the iliac attachment system  398  of the repair device are held between the inferior stop ring  321  and capsule  333 . When the sheath assembly  340  is retracted such that the superior end  344  is distal the superior end  334  of the main catheter  330 , the iliac attachment system  398  of the repair device  390  will deploy with the exception of the hooks  410  which are still pressed against the inferior stop ring  321  by the capsule  333 . 
     When it is time to deploy the hooks  410  of iliac attachment system  398  of the repair device  390 , the distal capsule lock mechanism  360  is unlocked and the main catheter  330  is retracted distally while holding the knob  326 . Such manipulation causes the capsule  333  to slide distally from the inferior stop ring  321  as shown in  FIG. 13 , thereby releasing the hooks  410  of the iliac attachment system  398  and permitting the completed implantation of the repair device  390  at the repair site. 
     Although use of the delivery system  310  was described with reference to the limb component  390  shown in  FIG. 16 , it is contemplated that the delivery system  310  may be utilized in the deployment of any multi-component repair device. The delivery system  310  facilitates reliable, simple and safe deployment of a repair device having opposing hooks at both ends through a small and tortuous path. It is further contemplated that the delivery system  310  may be scaled up or down to isolate and deploy hooks, barbs or eyelets of any size. 
     It will be apparent from the foregoing that, while particular forms of the invention have been illustrated and described, various modifications can be made without departing from the spirit and scope of the invention. Accordingly, it is not intended that the invention be limited, except as by the appended claims.