Patent Publication Number: US-2022211526-A1

Title: Branch stent graft and delivery method for endovascular treatment of the iliac artery aneurysms

Description:
RELATED APPLICATIONS 
     This application is a continuation application of U.S. patent application Ser. No. 16/661,343 filed on Oct. 23, 2019, the entire contents of which are incorporated herein by reference. 
    
    
     FIELD 
     The present technology is generally related to an intra-vascular device and method. More particularly, the present application relates to a device for treatment of intra-vascular diseases. 
     BACKGROUND 
     Iliac artery aneurysms in close proximity to the iliac bifurcation present an unmet clinical need for vascular surgeons versed in endovascular repair. One treatment option includes open surgery, which is highly invasive with associated long recovery and hospital stay times. 
     Another treatment option includes sacrificing the internal iliac artery by covering the internal iliac artery with a stent graft. Unfortunately, covering the internal iliac artery leads to poor quality of life from complications related to groin ischemia. 
     Yet another treatment option involves sealing a stent graft in the diseased (aneurysmal) common iliac artery. However, this option is associated with high rates of degeneration leading to future complications and reinterventions. 
     Challenges in the above options often lead the vascular surgeon to used limited commercially available iliac branch stent graft systems. The available iliac branch stent graft systems require high skill level, multiple accessory devices, and multiple surgical access points. 
     SUMMARY 
     The techniques of this disclosure generally relate to an iliac branch device having an external iliac body, a common iliac branch, and an internal iliac branch. A diameter of the proximal opening of the common iliac branch is greater than a diameter of a distal opening of the external iliac body. The iliac branch device is configured to be deployed without going up and over the aortic bifurcation and without using some form of supra-aortic antegrade access such as through brachial or axillary artery access. This simplifies the procedure and reduces procedure time thus maximizing the success rate of the procedure and allows the procedure to be performed on a broad patient population. 
     In one aspect, the present disclosure provides an assembly comprising an inner member and an iliac branch device having the inner member therein. The iliac branch device includes an external iliac body configured to be located within an external iliac artery, a common iliac branch configured to be located with a common iliac artery, and an internal iliac branch configured to perfuse an internal iliac artery. 
     In another aspect, the present disclosure provides a method comprising loading an iliac branch device within a delivery system having a handle. The iliac branch device includes an external iliac body, a common iliac branch, and an internal iliac branch. The external iliac body is proximal to both the common iliac branch and the internal iliac branch relative to the handle. 
     The details of one or more aspects of the disclosure are set forth in the accompanying drawings and the description below. Other features, objects, and advantages of the techniques described in this disclosure will be apparent from the description and drawings, and from the claims. 
    
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
         FIG. 1  is a perspective view of an iliac branch device in accordance with one embodiment. 
         FIG. 2  is a perspective view of an iliac branch device in accordance with another embodiment. 
         FIG. 3  is a perspective view of a delivery system including the iliac branch device of  FIG. 1  in accordance with one embodiment. 
         FIG. 4  is a partial cross-sectional view of a vessel assembly including the iliac branch device of  FIG. 1  in accordance with one embodiment. 
         FIG. 5  is an enlarged view of the region V of the vessel assembly of  FIG. 4  in accordance with one embodiment. 
         FIG. 6  is a partial cross-sectional view of the vessel assembly of  FIG. 5  at a later stage during deployment of a bridging graft in accordance with one embodiment. 
         FIG. 7  is an enlarged view of the region V of the vessel assembly of  FIG. 4  after deployment of the iliac branch device of  FIG. 2  in accordance with one embodiment. 
         FIG. 8  is a partial cross-sectional view of the vessel assembly of  FIG. 7  at a later stage during deployment of a bridging graft in accordance with one embodiment. 
         FIG. 9  is a partial cross-sectional view of the vessel assembly of  FIG. 6  at a later stage after deployment of an aortic bifurcated stent graft in accordance with one embodiment. 
         FIG. 10A  is an enlarged view of the region X of the vessel assembly of  FIG. 9  in accordance with one embodiment. 
         FIG. 10B  is an enlarged view of the region X of the vessel assembly of  FIG. 9  in accordance with another embodiment. 
         FIG. 11  is a partial cross-sectional view of the vessel assembly of  FIG. 6  at a later stage after deployment of an aortic bifurcated stent graft in accordance with another embodiment. 
         FIG. 12  is an enlarged view of the region V of the vessel assembly of  FIG. 4  in accordance with one embodiment. 
     
    
    
     DETAILED DESCRIPTION 
       FIG. 1  is a perspective view of an iliac branch device  100  in accordance with one embodiment. Iliac branch device  100  includes an external iliac body  102 , internal iliac branch  104 , and a common iliac branch  106 . External iliac body  102 , internal iliac branch  104 , and common iliac branch  106  are sometimes called an external iliac body  102 , a first bifurcated leg  104 , and a second bifurcated leg  106 , respectively. 
     In accordance with this embodiment, external iliac body  102  includes distal opening  108  at a distal end  110  of external iliac body  102 . A proximal end  112  of external iliac body  102  is coupled to a proximal end  114  of internal iliac branch  104  and a distal end  116  of common iliac branch  106 . 
     Internal iliac branch  104  includes an internal iliac distal opening  118  at a distal end  120  of internal iliac branch  104 . Common iliac branch  106  includes a common iliac proximal opening  122  at a proximal end  124  of common iliac branch  106 . 
     As used herein, the proximal end of a prosthesis such as iliac branch device  100  is the end closest to the heart via the path of blood flow whereas the distal end is the end furthest away from the heart during deployment. As discussed below, blood flow enters into proximal opening  122  of common iliac branch  106  and exits distal openings  108 ,  118  of external iliac body  102  and internal iliac branch  104  respectively. Generally, there is retrograde blood flow through internal iliac branch  104 . Accordingly, proximal end  112  of external iliac body  102  is coupled to proximal end  114  of internal iliac branch  104  and distal end  116  of common iliac branch  106  at a transition region  126 . 
     In contrast and of note, the distal end of the delivery system is usually identified to the end that is farthest from the operator/handle while the proximal end of the delivery system is the end nearest the operator/handle. For purposes of clarity of discussion, as used herein, the distal end of the delivery system is the end that is farthest from the operator (the end furthest from the handle). However, those of skill in the art will understand that depending upon the access location, iliac branch device  100  and/or the delivery system descriptions may be different in actual usage. 
     Iliac branch device  100  includes graft material  128  and one or more circumferential stents  130  coupled to graft material  128 . Graft material  128  may be any suitable graft material, for example and not limited to, woven polyester, DACRON® material, expanded polytetrafluoroethylene, polyurethane, silicone, electro spun materials, or other suitable materials. 
     Circumferential stents  130  may be coupled to graft material  128  using stitching or other means. In the embodiment shown in  FIG. 1 , circumferential stents  130  are coupled to an outside surface of graft material  128 . However, circumferential stents  130  may alternatively be coupled to an inside surface of graft material  128 . 
     Although shown with a particular number of circumferential stents  130 , in light of this disclosure, those of skill in the art will understand that iliac branch device  100  may include a greater or smaller number of stents  130 , e.g., depending upon the desired length of external iliac body  102 , internal iliac branch  104 , and common iliac branch  106  and/or the intended application thereof. 
     Circumferential stents  130  may be any stent material or configuration. As shown, circumferential stents  130 , e.g., self-expanding members, are preferably made from a shape memory material, such as nickel-titanium alloy (nitinol), and are formed into a zig-zag configuration. The configuration of circumferential stents  130  is merely exemplary, and circumferential stents  130  may have any suitable configuration, including but not limiting to a continuous or non-continuous helical configuration. In another embodiment, circumferential stents  130  are balloon expandable stents. In one embodiment, bare stents and/or delivery system interfaces which increase control over delivery are included. Further, in one embodiment, there are radiopaque markers that assist in orientating iliac branch device  100 . 
     A lumen  132  is defined by external iliac body  102 . Lumen  132  extends between distal opening  108  and proximal end  112  of external iliac body  102 . External iliac body  102  increases in diameter from distal opening  108  to proximal end  112 . However, in other embodiments, external iliac body  102  is uniform in diameter or decreases in diameter from distal opening  108  to proximal end  112 . 
     Further, a lumen  134  is defined by internal iliac branch  104 . Lumen  134  extends between proximal end  114  and distal opening  118  of internal iliac branch  104 . Internal iliac branch  104  is cylindrical having a substantially uniform diameter in this embodiment. However, in other embodiments, internal iliac branch  104  varies in diameter. 
     Further, a lumen  136  is defined by common iliac branch  106 . Lumen  136  extends between proximal opening  122  and distal end  116  of common iliac branch  106 . Common iliac branch  106  decreases in diameter from proximal opening  122  to distal end  116 . However, in other embodiments, common iliac branch  106  is uniform in diameter or increases in diameter from proximal opening  122  to distal end  116 . 
     Generally, external iliac body  102  is bifurcated at proximal end  112  (transition region  126 ) into internal iliac branch  104  and common iliac branch  106 . More particularly, lumen  132  of external iliac body  102  is bifurcated into lumen  134  of internal iliac branch  104  and lumen  136  of common iliac branch  106 . 
     In accordance with this embodiment, openings  108 ,  118 , and  122  of external iliac body  102 , internal iliac branch  104 , and common iliac branch  106  have diameters D 1 , D 2 , and D 3 , respectively, in their relaxed and expanded configuration. Illustratively, diameter D 3  is in the range of 12 to 28 millimeters (mm), diameter D 2  is less than 12 mm, and diameter D 1  is in the range of 8 to 14 mm. 
     In one embodiment, diameter D 3  of opening  122  of common iliac branch  106  is greater than either of diameters D 1  and D 2  of opening  108  of external iliac body  102  and opening  118  of internal iliac branch  104 , respectively. However, in other embodiments, diameter D 1  is greater than or equal to diameter D 3 , e.g., diameter D 3  is 12 mm and diameter D 1  is up to 14 mm. 
       FIG. 2  is a perspective view of an iliac branch device  100 A in accordance with another embodiment. Iliac branch device  100 A of  FIG. 2  is similar to iliac branch device  100  of  FIG. 1  and only the significant differences are discussed below. More particularly, iliac branch device  100 A includes external iliac body  102  and common iliac branch  106  which are similar or identical to external iliac body  102  and common iliac branch  106  of iliac branch device  100  and so are not discussed further. 
     Referring now to  FIG. 2 , an internal iliac branch  104 A is curved, sometimes called having a hook shape, a “J” shape, or a “candy cane” shape. More particular, internal iliac branch  104 A curves away from common iliac branch  106  such that distal opening  118  points away from common iliac branch  106 . The curved shape of internal iliac branch  104 A facilitates cannulation of the internal iliac artery as discussed further below. 
     In one embodiment, internal iliac branch  104 A includes a curving member  238  that curves internal iliac branch  104 A. Curving member  238  includes a curved wire, stitching, or other feature that curves internal iliac branch  104 A in various embodiments. A pre-shaped, curved wire could be constructed from a superelastic or traditional alloy and be attached to the inner curve of the flexible internal iliac branch  104 A to force curvature. The attachment could be to the inside or outside of internal iliac branch  104 A by way of suture material. Alternatively, a seamed channel could be created in the graft material of internal iliac branch  104 A with the wire floating freely inside. A second (or multiple) wires(s) could further act to form this shape. Alternatively, a stitching pattern could establish a morphology of the graft material of internal iliac branch  104 A that when pressurized would assume the hook shape, thus eliminating the need for a wire member. 
       FIG. 3  is a perspective view of a delivery system  300  including iliac branch device  100  of  FIG. 1  in accordance with one embodiment. Delivery system  300  includes a first inner member  302 , a first guidewire  304 , a second inner member  306 , a second guidewire  308 , a distal tip  310 , a sheath  312 , and a handle  314 . 
     As illustrated in  FIG. 3 , first and second guidewires  304 ,  308  extend through lumens in first and second inner members  302 ,  306 . Inner members  302 ,  306  and guidewires  304 ,  308  extend distally from handle  314  and within sheath  312 . Handle  314  has various mechanisms and ports to allow manipulation, e.g. retraction or advancement, of guidewires  304 ,  308 , sheath  312  and/or inner members  302 ,  306  relative to one another. 
     Distal tip  310  is coupled to first inner member  302 , e.g., the distal end thereof, and has a guidewire port  316  through which guidewire  304  extends. Second inner member  306  is located between first inner member  302  and sheath  312  in this embodiment. 
     Iliac branch device  100  is loaded within delivery system  300 . More particularly, external iliac body  102  and common iliac branch  106  are loaded over first inner member  302 . In other words, first inner member  302  enters distal opening  108  of external iliac body  102 , extends through both external iliac body  102  and common iliac branch  106  and exits proximal opening  122  of common iliac branch  106 . 
     Further, external iliac body  102  and internal iliac branch  104  are loaded over second inner member  306 . In other words, second inner member  306  enters distal opening  108  of external iliac body  102 , extends through both external iliac body  102  and internal iliac branch  104  and exits distal opening  118  of internal iliac branch  104 . Second guidewire  308  is sometimes called a prewired guidewire  308  in accordance with this embodiment. 
     Although delivery system  300  is illustrated and discussed as including both inner members  302 ,  306  and guidewires  304 ,  308 , in another embodiment, delivery system includes either inner member  302 /guidewire  304  or inner member  306 /guidewire  308 , but not both. 
     Further, although a particular arrangement of loading of iliac branch device  100  within delivery system  300  is illustrated and discussed, other arrangements and delivery systems are used in other embodiments. Generally, iliac branch device  100  is loaded such that external iliac body  102  is proximal (relative to handle  314 ) to both internal iliac branch  104  and common iliac branch  106 . Iliac branch device  100  is sometime said to be loaded backwards within the delivery system. 
     Two guidewires are potentially used. The primary guidewire runs through common iliac branch  106 . The second guidewire runs through internal iliac branch  104 . In other embodiments, a single guidewire is used. Other arrangements are possible. 
       FIG. 3  illustrates delivery system  300  in a deployed (or pre-loading) state where sheath  312  is withdrawn to expose iliac branch device  100  for purposes of illustrating the various features of delivery system  300 . When in a delivery state, sheath  312  abuts distal tip  310  and iliac branch device  100  is constrained between sheath  312  and inner members  302 ,  306 . 
     To deploy iliac branch device  100 , delivery system  300  is advanced over first guidewire  304  to the desired deployment location. For example, delivery system  300  is introduced through an ipsilateral external iliac artery access point and advanced to the desired deployment location. Once at the deployment location, sheath  312  is retracted thus releasing iliac branch device  100 . Once released, iliac branch device  100 , e.g., stents  130 , self-expands (or is balloon expanded) to be secured in the deployment location. 
     In one embodiment, upon retraction of sheath  312  and deployment of iliac branch device  100 , iliac branch device  100  assumes a configuration similar to that illustrated in  FIG. 1 . In accordance with this embodiment, internal iliac branch  104  is deployed as a straight member. 
     In another embodiment, second inner member  306  is a resilient curved member. Second inner member  306  is constrained in a straight state by sheath  312  when in a delivery state. Upon being deployed and released from sheath  312 , second inner member  306  resumes the curved state of second inner member  306 . Curvature of second inner member  306  causes curvature of internal iliac branch  104  as illustrated by the dashed lines in  FIG. 3 . 
     In another embodiment, iliac branch device  100 A of  FIG. 2  is loaded within delivery system  300  instead of iliac branch device  100  of  FIG. 1 . In accordance with this embodiment, referring to  FIGS. 2-3  together, internal iliac branch  104 A is constrained in a straight state by sheath  312  when in a delivery state. Upon being deployed and released from sheath  312 , internal iliac branch  104 A resumes the curved state of internal iliac branch  104 A as illustrated by the dashed lines in  FIG. 3 . 
       FIG. 4  is a partial cross-sectional view of a vessel assembly  400  including iliac branch device  100  of  FIG. 1  in accordance with one embodiment.  FIG. 5  is an enlarged view of the region V of vessel assembly  400  of  FIG. 4  in accordance with one embodiment. Referring to  FIGS. 4 and 5  together, vessel assembly  400  illustrates a series of vessels within the human body, including the aorta  402 , the common iliac arteries  404 ,  406 , internal iliac arteries  408 ,  410 , and external iliac arteries  412 ,  414 . 
     More particularly, the aorta  402  descends to an aortic bifurcation  416  from which extends common iliac arteries  404 ,  406 . Common iliac artery  404  descends to a common iliac artery bifurcation  418  from which extends internal iliac artery  408  and external iliac artery  412  at a contralateral side. Similarly, common iliac artery  406  descends to a common iliac artery bifurcation  420  from which extends internal iliac artery  410  and external iliac artery  414  at an ipsilateral side. In accordance with this example, common iliac artery  406  includes an iliac artery aneurysm  422 , i.e., a diseased section of tissue. 
     Referring now to  FIGS. 3 and 5  together, iliac branch device  100  is deployed within common iliac artery  406  and external iliac artery  414 . For example, as discussed above, delivery system  300  introduced through an ipsilateral external iliac artery access point and advanced to the desired deployment location within common iliac artery  406  and external iliac artery  414 . Sheath  312  is retracted such that iliac branch device  100  is deployed with common iliac branch  106  within common iliac artery  406  and external iliac body  102  is deployed within external iliac artery  414 . Distal opening  118  is adjacent to common iliac artery bifurcation  420  and generally adjacent or distal of the ostium of internal iliac artery  410 . External iliac body  102  provides the distal seal within external iliac artery  414 . 
     In accordance with this embodiment, second guidewire  308  is located within internal iliac artery  410 . For example, second guidewire  308  is prewired as discussed above in reference to  FIG. 3  and delivery system  300 . However, in another embodiment, delivery system  300  does not include prewired guidewire  308 , and guidewire  308  is advanced and manipulated to cannulate internal iliac artery  410 . 
       FIG. 6  is a partial cross-sectional view of vessel assembly  400  of  FIG. 5  at a later stage during deployment of a bridging graft  602  in accordance with one embodiment. Referring now to  FIGS. 5 and 6  together, bridging graft  602  is deployed within internal iliac branch  104  and internal iliac artery  410 . 
     To deploy bridging graft  602 , a delivery system including bridging graft  602  is inserted at the same access point as the access point used for iliac branch device  100 , e.g., the ipsilateral external iliac artery access point. The delivery system is advanced over guidewire  308  and into internal iliac artery  410 . Bridging graft  602  is then deployed from the delivery system, e.g., by withdrawing a sheath thereof. Upon deployment, bridging graft  602  self-expands (or is balloon expanded) to be located within internal iliac branch  104  and internal iliac artery  410 . Guidewire  308  is removed. 
     Bridging graft  602  bridges blood flow from internal iliac branch  104  to internal iliac artery  410 . In one embodiment, bridging graft  602  includes graft material  604  and one or more stents  606 . Graft material  604  and stents  606  are the same or similar to graft material  128  and stents  130  as discussed above. 
     Referring now to  FIGS. 1, 4, and 6  together, once deployed, blood flow enters into proximal opening  122  of common iliac branch  106 . Blood flows through lumen  136  of common iliac branch  106  to transition region  126 . At transition region  126 , a portion of the blood flows through lumen  132  of external iliac body  102  and out distal opening  108 . Another portion of the blood flows through lumen  134  of internal iliac branch  104 , through bridging graft  602 , and perfuses internal iliac artery  410 . Blood flow through internal iliac branch  104  is retrograde (backwards) blood flow. However, there is a sufficient amount of perfusion of internal iliac artery  410  through the retrograde blood flow to avoid serious medical complication from obstruction of internal iliac artery  410 . 
     Iliac branch device  100  and bridging graft  602  are deployed from the same ipsilateral external iliac artery access point. Of note, iliac branch device  100  and bridging graft  602  are deployed without going up and over aortic bifurcation  416  and without using some form of supra-aortic antegrade access such as through brachial or axillary artery access. This simplifies the procedure and reduces procedure time thus maximizing the success rate of the procedure and allows the procedure to be performed on a broad patient population. 
       FIG. 7  is an enlarged view of the region V of vessel assembly  400  of  FIG. 4  after deployment of iliac branch device  100 A of  FIG. 2  in accordance with one embodiment. The deployment of iliac branch device  100 A of  FIG. 7  is similar to the deployment of iliac branch device  100  of  FIG. 5  and only the significant differences are discussed below. 
     In accordance with this embodiment, distal opening  118  of internal iliac branch  104 A is located directly adjacent and proximal to the ostium of internal iliac artery  410 . Due to the curvature of internal iliac branch  104 A, distal opening  118  points towards the ostium of internal iliac artery  410 . This simplifies cannulation of internal iliac artery  410  with guidewire  308  as the curvature of internal iliac branch  104 A facilitates guiding of guidewire  308 . 
       FIG. 8  is a partial cross-sectional view of vessel assembly  400  of  FIG. 7  at a later stage during deployment of bridging graft  602  in accordance with one embodiment. Referring now to  FIGS. 7 and 8  together, bridging graft  602  is deployed within internal iliac branch  104 A and internal iliac artery  410  in a manner similar to that discussed above regarding deployment of bridging graft  602  into internal iliac branch  104  and internal iliac artery  410  of  FIG. 6 . 
       FIG. 9  is a partial cross-sectional view of vessel assembly  400  of  FIG. 6  at a later stage after deployment of an aortic bifurcated stent graft  900  in accordance with one embodiment. Referring now to  FIGS. 4, 6, and 9  together, in accordance with this embodiment, aorta  402  includes an aortic aneurysm  424 . In accordance with this embodiment, aortic bifurcated stent graft  900  excludes aortic aneurysm  424 . However, in another embodiment, aorta  402  is healthy, i.e., does not include an aneurysm. 
     More particularly, aortic bifurcated stent graft  900  includes a main body  902 , a first leg  904 , and a second leg  906 . Examples of aortic bifurcated stent graft  900  includes the Endurant® II AAA stent graft system manufactured by Medtronic or other AAA EVAR devices. 
     In one embodiment, aortic bifurcated stent graft  900  is deployed distal of renal arteries  426 ,  428  although the deployment location various in other embodiments depending upon the particular application of aortic bifurcated stent graft  900 . A first bridging graft  908  is deployed within and bridges first leg  904  and common iliac artery  404 . A second bridging graft  910  is deployed within and bridges second leg  906  and common iliac branch  106 . 
       FIG. 10A  is an enlarged view of the region X of vessel assembly  400  of  FIG. 9  in accordance with one embodiment.  FIG. 10A  illustrates a first component A within a second component B. 
     Referring now to  FIGS. 9 and 10A  together, illustratively, aortic bifurcated stent graft  900  and iliac branch device  100  are initially deployed. After deployment of aortic bifurcated stent graft  900  and iliac branch device  100 , bridging graft  910  is deployed within second leg  906  and common iliac branch  106 . In accordance with this embodiment, first component A is representative of bridging graft  910  and second component B is representative of common iliac branch  106 . As illustrated in  FIG. 10A , bridging graft  910  (component A) is deployed within and overlaps common iliac branch  106  (component B) thus forming a seal between bridging graft  910  and common iliac branch  106 . 
       FIG. 10B  is an enlarged view of the region X of vessel assembly  400  of  FIG. 9  in accordance with another embodiment.  FIG. 10B  illustrates second component B within first component A. 
     Referring now to  FIGS. 9 and 10B  together, in accordance with this embodiment, aortic bifurcated stent graft  900  and bridging graft  910  are initially deployed. Illustratively, aortic bifurcated stent graft  900  and bridging graft  910  provide sufficient exclusion of aortic aneurysm  424 . 
     However, after a period of time, aortic bifurcated stent graft  900  and bridging graft  910  do not provide sufficient exclusion. Illustratively, aortic aneurysm  424  grows and/or iliac aneurysm  422  is formed or grows. Accordingly, at a later point in time in a follow on procedure, iliac branch device  100  is deployed to provide sufficient exclusion of aneurysms  422  and/or  424 . 
     More particularly, common iliac branch  106  is deployed within bridging graft  910 . In accordance with this embodiment, first component A is representative of bridging graft  910  and second component B is representative of common iliac branch  106 . As illustrated in  FIG. 10B , common iliac branch  106  (component B) is deployed within and overlaps bridging graft  910  (component A) thus forming a seal between common iliac branch  106  and bridging stent graft  910 . 
     In yet another embodiment, aortic bifurcated stent graft  900  and bridging stent graft  910  are initially deployed and iliac branch device  100  is then deployed in a single procedure. 
       FIG. 11  is a partial cross-sectional view of vessel assembly  400  of  FIG. 6  at a later stage after deployment of aortic bifurcated stent graft  900  in accordance with another embodiment. Vessel assembly  400  as illustrated in  FIG. 11  is similar to vessel assembly  400  as illustrated in  FIG. 9  except bridging graft  910  of  FIG. 9  is not used in accordance with the embodiment of  FIG. 11 . 
     Referring now to  FIGS. 4, 6, and 11  together, in accordance with this embodiment, common iliac branch  106  is joined directly with second leg  906  of aortic bifurcated stent graft  900 . Illustratively, second leg  906  and/or common iliac branch  106  are extended to overlap one another. 
       FIG. 10B  is an enlarged view of the region X of vessel assembly  400  of  FIG. 11  in accordance with this embodiment. Referring now to  FIGS. 10B and 11  together, in accordance with this embodiment, aortic bifurcated stent graft  900  is initially deployed. Illustratively, aortic bifurcated stent graft  900  provides sufficient exclusion of aortic aneurysm  424 . 
     However, after a period of time, aortic bifurcated stent graft  900  does not provide sufficient exclusion. Illustratively, aortic aneurysm  424  grows and/or iliac aneurysm  422  is formed or grows. Accordingly, iliac branch device  100  is deployed to provide sufficient exclusion of aneurysms  422  and/or  424 . 
     More particularly, common iliac branch  106  is deployed within second leg  906 . In accordance with this embodiment, first component A is representative of second leg  906  and second component B is representative of common iliac branch  106 . As illustrated in  FIG. 10B , common iliac branch  106  (component B) is deployed within and overlaps second leg  906  (component A) thus forming a seal between common iliac branch  106  and second leg  906 . 
     In yet another embodiment, aortic bifurcated stent graft  900  is initially deployed and iliac branch device  100  is then deployed in a single procedure. 
       FIG. 12  is an enlarged view of the region V of vessel assembly  400  of  FIG. 4  in accordance with one embodiment. Referring to  FIGS. 4 and 12  together, in accordance with this embodiment, vessel assembly  400  includes only an isolated iliac aneurysm  422 . In accordance with this embodiment, iliac branch device  100  alone provides sufficient exclusion of iliac aneurysm  422 . Illustratively, common iliac branch  106  forms a proximal seal with common iliac artery  406 . External iliac body  102  forms a distal seal with external iliac artery  414 . Internal iliac branch  104  and bridging graft  602  form the distal seal with internal iliac artery  410 . In this manner, isolated iliac aneurysm  422  is excluded by iliac branch device  100  alone. 
     In one embodiment, after a period of time, iliac branch device  100  does not provide sufficient exclusion. Illustratively, aortic aneurysm  424  is formed and/or iliac aneurysm  422  grows. Accordingly, aortic bifurcated stent graft  900  is deployed to provide sufficient exclusion of aneurysms  422  and/or  424 . 
     More particularly, referring to  FIGS. 10A, 11-12 , second leg  906  of aortic bifurcated stent graft  900  is deployed with common iliac branch  106 . In accordance with this embodiment, first component A is representative of second leg  906  and second component B is representative of common iliac branch  106 . As illustrated in  FIG. 10A , second leg  906  is deployed within and overlaps common iliac branch  106  thus forming a seal between common iliac branch  106  and second leg  906 . 
     In yet another embodiment, iliac branch device  100  is initially deployed and aortic bifurcated stent graft  900  is then deployed in a single procedure. 
     Although  FIGS. 9, 10A, 10B, 11 and 12  are discussed above as including iliac branch device  100  of  FIG. 1 , in other embodiments, iliac branch device  100 A as illustrated in  FIG. 2  is used in place of iliac branch device  100 . Accordingly, the discussion regarding iliac branch device  100  in  FIGS. 9, 10A, 10B, 11-12  is equally applicable to iliac branch device  100 A. 
     It should be understood that various aspects disclosed herein may be combined in different combinations than the combinations specifically presented in the description and accompanying drawings. It should also be understood that, depending on the example, certain acts or events of any of the processes or methods described herein may be performed in a different sequence, may be added, merged, or left out altogether (e.g., all described acts or events may not be necessary to carry out the techniques). In addition, while certain aspects of this disclosure are described as being performed by a single module or unit for purposes of clarity, it should be understood that the techniques of this disclosure may be performed by a combination of units or modules associated with, for example, a medical device.