Abstract:
Systems and methods introduce and deploy prosthesis into a blood vessel or hollow body organ. The prosthesis is secured in place by fasteners, and includes a region or regions specially sized and configured to receive and retain the fasteners.

Description:
RELATED APPLICATION  
       [0001]     This application claims the benefit of U.S. patent application Ser. No. 10/693,255, filed Oct. 24, 2003, and entitled “Multi-Lumen Prosthesis Systems and Methods.” 
     
    
     FIELD OF THE INVENTION  
       [0002]     The invention relates generally to prostheses, and in particular, to prostheses used in the repair of diseased and/or damaged sections of a hollow body organ and/or a blood vessel.  
       BACKGROUND OF THE INVENTION  
       [0003]     The weakening of a vessel wall from damage or disease can lead to vessel dilatation and the formation of an aneurysm. Left untreated, an aneurysm can grow in size and may eventually rupture.  
         [0004]     For example, aneurysms of the aorta primarily occur in abdominal region, usually in the infrarenal area between the renal arteries and the aortic bifurcation. Aneurysms can also occur in the thoracic region between the aortic arch and renal arteries. The rupture of an aortic aneurysm results in massive hemorrhaging and has a high rate of mortality.  
         [0005]     Open surgical replacement of a diseased or damaged section of vessel can eliminate the risk of vessel rupture. In this procedure, the diseased or damaged section of vessel is removed and a prosthetic graft, made either in a straight of bifurcated configuration, is installed and then permanently attached and sealed to the ends of the native vessel by suture. The prosthetic grafts for these procedures are usually unsupported woven tubes and are typically made from polyester, ePTFE or other suitable materials. The grafts are longitudinally unsupported so they can accommodate changes in the morphology of the aneurysm and native vessel. However, these procedures require a large surgical incision and have a high rate of morbidity and mortality. In addition, many patients are unsuitable for this type of major surgery due to other co-morbidities.  
         [0006]     Endovascular aneurysm repair has been introduced to overcome the problems associated with open surgical repair. The aneurysm is bridged with a vascular prosthesis, which is placed intraluminally. Typically these prosthetic grafts for aortic aneurysms are delivered collapsed on a catheter through the femoral artery. These grafts are usually designed with a fabric material attached to a metallic scaffolding (stent) structure, which expands or is expanded to contact the internal diameter of the vessel. Unlike open surgical aneurysm repair, intraluminally deployed grafts are not sutured to the native vessel, but rely on either barbs extending from the stent, which penetrate into the native vessel during deployment, or the radial expansion force of the stent itself is utilized to hold the graft in position. These graft attachment means do not provide the same level of attachment when compared to suture and can damage the native vessel upon deployment.  
       SUMMARY OF THE INVENTION  
       [0007]     The invention provides apparatus and methods for repairing diseased and/or damaged sections of a hollow body organ and/or a blood vessel.  
         [0008]     One aspect of the invention provides systems and methods that include a prosthesis for a blood vessel or hollow body organ. The prosthesis comprises a trunk that includes a prosthetic material and a scaffold. The scaffold supports the prosthetic material to define a lumen within the trunk. The trunk includes a main body region and a fastening region. The fastening region is configured differently than the main body region for the receipt and retention in the second region of at least one fastener implanted into tissue by an external fastener attachment assembly.  
         [0009]     The different configuration of the fastening region can comprise, e.g., a prosthetic material in the fastening region that is different than a prosthetic material in the main body region; and/or a prosthetic material in the fastening region that includes more layers than the prosthetic material in the main body region; and/or a prescribed weave pattern in the fastening region that is not present in the main body region; and/or a prescribed weave pattern in the fastening region that is denser that a weave pattern in the main body region; and/or a scaffold configuration in the fastening region that is different than a scaffold configuration in the main body region.  
         [0010]     Other features and advantages of the invention shall be apparent based upon the accompanying description, drawings, and claims. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0011]     The invention will be understood from the following detailed description of preferred embodiments, taken in conjunction with the accompanying drawings, wherein:  
         [0012]      FIG. 1  is a perspective view of a tissue reinforcement prosthesis having a fastening region that accommodates the introduction of one or more fasteners.  
         [0013]      FIG. 2  is a perspective view of a prosthesis system that includes the tissue reinforcement prosthesis shown in  FIG. 1  and an auxiliary prosthesis that, in use, is telescopically anchored and supported by the tissue reinforcement prosthesis.  
         [0014]      FIG. 3  is a perspective view of the tissue reinforcement prosthesis shown in  FIG. 1 , showing the attachment of fasteners in the fastening region.  
         [0015]      FIG. 4  is a perspective view of the tissue reinforcement prosthesis shown in  FIG. 1  positioned within a hollow body organ by use of fasteners.  
         [0016]      FIG. 5A  is a perspective view of the tissue reinforcement prosthesis shown in  FIG. 1  positioned within the proximal neck of an abdominal aortic aneurysm.  
         [0017]      FIG. 5B  is a perspective view of the tissue reinforcement prosthesis shown in  FIG. 5A , with the inclusion of an optional supra-renal stent.  
         [0018]      FIG. 6A  is a perspective view of a prosthesis system that includes the tissue reinforcement prosthesis shown in  FIG. 5A  positioned within a proximal neck of the abdominal aortic aneurysm and an auxiliary prosthesis that is telescopically anchored and supported by the tissue reinforcement prosthesis and that bridges the aneurysm.  
         [0019]      FIG. 6B  is an enlarged view of the system shown in  FIG. 6A , showing the telescopic fitment of the auxiliary prosthesis in the tissue reinforcement prosthesis.  
         [0020]      FIG. 6C  is an enlarged view of the system shown in  FIG. 6A , showing a telescopic, interlocking fitment of the auxiliary prosthesis in the tissue reinforcement prosthesis.  
         [0021]      FIGS. 7, 8 , and  9  are perspective views of the deployment of the system shown in  FIG. 6A  by the sequential use of various intra-vascular catheters, one to deploy the tissue reinforcement prosthesis ( FIG. 7 ), another to apply fasteners to the tissue reinforcement prosthesis ( FIG. 8 ), and another to deploy the auxiliary prosthesis ( FIG. 9 ).  
         [0022]      FIG. 10  is a perspective view of prosthesis positioned within an abdominal aortic aneurysm, the prosthesis having a fastening region that accommodates the introduction of one or more fasteners.  
         [0023]      FIG. 11  is a perspective view of prosthesis positioned within an abdominal aortic aneurysm, the prosthesis having a tapered trunk located, at its proximal end, within the aorta and, at its distal end, in an iliac, the prosthesis also having a fastening region that accommodates the introduction of one or more fasteners. 
     
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [heading-0024]     I. Tissue Reinforcement Prosthesis  
         [0025]     A. Structure  
         [0026]      FIG. 1  shows a tissue reinforcement prosthesis  10  that embodies features of the invention. The prosthesis  10  serves to reinforce a region of a vessel wall or hollow body organ which has been weakened by disease or damage. As will be described in greater detail later, the prosthesis  10  desirable provides a platform on which to deploy a second prosthesis  36  (see  FIG. 2 ) in the vessel or hollow body organ. In this arrangement, the reinforcement prosthesis  10  comprises a component part of an overall prosthesis system  52 .  
         [0027]     In the illustrated embodiment (see  FIG. 1 ), the prosthesis  10  comprises a tubular trunk  12 . The trunk  12  is sized and configured to fit within a targeted region of a hollow body organ and/or a blood vessel. The targeted region is selected on the basis of certain anatomic characteristics. These characteristics include a weakened conditioned caused, e.g., by disease or damage.  
         [0028]     The trunk  12  forms a generally cylindrical structure with an open interior lumen  18 . The trunk  12  fortifies the body organ or blood vessel in the targeted region, to keep it from collapsing.  
         [0029]     In the illustrated embodiment, the trunk  12  includes a prosthetic material  14  supported by a scaffold  16 . The prosthetic material  14  is selected on the basis of its biocompatibility, durability, and flexible mechanical properties. The material  14  can comprise, e.g., woven polyester. Alternatively, a material comprising ePTFE can be used.  
         [0030]     The scaffold  16  is desirable sized and configured to permit non-invasive deployment of the prosthesis  10  by an intra-vascular catheter. With this criteria in mind, the scaffold  16  is sized and configured to assume a compressed or collapsed, low profile condition, to permit its intra-vascular introduction into the hollow body organ and/or blood vessel by a catheter, as will be described in greater detail later.  
         [0031]     Also with this criteria in mind, the scaffold  16  is sized and configured for expansion in situ from its collapsed condition into an expanded condition in contact with tissue in the targeted region, as will also be described in greater detail later.  
         [0032]     In this respect, the scaffold  16  can comprise, e.g., a malleable plastic or metal material that expands in the presence of an applied force. In this arrangement, the deployment catheter can include, e.g., an expandable body, such as a balloon, to apply the expansion force to the scaffold  16  in situ.  
         [0033]     Alternatively, the scaffold  16  can comprise a self-expanding plastic or metal material that can be compressed in the presence of a force, but self-expands upon removal of the compressive force. In this arrangement, the deployment catheter can include, e.g., a sleeve that can be manipulated to enclosed the scaffold  16  in a collapsed condition, thereby applying the compressive force, and to release the scaffold  16  when desired to allow the scaffold  16  to self-expand in situ.  
         [0034]     For self-expansion, the scaffold  16  can include individual self-expanding, zigzag type main stent rings  22 . The main stent rings  22  can be made, e.g., from Nitinol® wire. Still, other materials, manufacturing methods and designs can be used.  
         [0035]     The main stent rings  22  need not be attached to one another throughout the prosthesis material  14 . The individual main stent rings  22  allow for longitudinal compliance while maintaining radial support of the open interior lumen  18 . This technical feature allows the prosthesis  10  to more readily accommodate changes in morphology in the targeted region. Still, it may be desirable in certain locations within the prosthesis structure to have attachments between the individual main stent rings  22  to provide enhanced stability and/or additional radial support.  
         [0036]     Each of the main stent rings  22  can be, e.g., sewn onto prosthetic material  14 . In the illustrated embodiment, in which the prosthetic material  14  is woven polyester, the attachment of the main stent rings  22  can be made, e.g., with polyester suture.  
         [0037]     However, it is also contemplated that other attachment means could be utilized to secure the main stent rings  22  to the prosthetic material  14 . These means include bonding; capturing the main stent rings  22  between two layers of prosthetic material  14 ; and incorporating the main stent rings  22  directly into the prosthetic material  14 .  
         [0038]     In certain locations it is desired to have the main stent rings  22  attached to the outer diameter of the prosthetic material  14 . Still, it is also contemplated that the main stent rings  22  could be attached to the inner diameter of the prosthetic material  22 .  
         [0039]     At least one end of the trunk  12  desirably also includes one or more end stent rings  24 . The principal purpose of an end stent ring  24  is to provide a seal between the trunk  12  and adjoining tissue. This sealing function is particularly desirable when the prosthesis  10  is deployed in a blood vessel or other body organ, where body fluids are intended to reside or pass through the prosthesis  10 . The end sent rings  24  can also serve, with the main stent rings  22 , to help maintain the position of the prosthesis  10  in the targeted region.  
         [0040]     Since the end stent rings  24  desirably serve more of a sealing function than a retention function, the end stent rings  24  are desirably more compliant than the main stent rings  22 . The end stent rings  24  also desirably occupy a minimum of area on the trunk  12 .  
         [0041]     The trunk  12  (material  14  and/or scaffold  16 ) can carry radiopaque markers  46  to help fluoroscopically position the prosthesis  10 . The markers  46  can take the form, e.g. of marker bands, tight wound coils, or wire made from radiopaque materials such as platinum, platinum/iridium, or gold.  
         [0042]     The trunk  12  also desirably includes at least one fastening region  26  that accommodates the introduction of one or more fasteners  28  to anchor the prosthesis  10  in place (see  FIG. 3 ). It is desirable that this region  26  of the trunk  12  be specially sized and configured for the receipt and retention of fasteners  28 . For example, the size and spacing of ring stent patterns can be configured in the region  26  to specially accommodate the placement of fasteners; and/or woven fibers with an “X-pattern” or a “sinusoidal pattern” can be used in the region  26  to specially accommodate placement of fasteners; and/or the prosthetic material  14  can be folded-over to form multiple layers, to reinforce the prosthesis in the region  26  where fasteners are placed; and/or denser weave patterns or stronger fibers can be used, selected from, e.g., Kevlar™ material or Vectran™ material or metallic wire woven alone or interwoven with typical polyester fibers in the region  26  were fasteners are placed. It may also be desirable to fluoroscopically indicate this region  26  with auxiliary radiopaque markers  30  on the prosthetic material  14 , and/or auxiliary stent rings  32  to aid in positioning the fasteners.  
         [0043]     The fasteners  28  can be variously constructed. They can, e.g., comprise helical fasteners or staples.  
         [0044]     Desirably, like the prosthesis  10  itself, the fasteners  28  are introduced by an intra-vascular fastener attachment assembly. Details of a fastener attachment assembly that deploys helical fasteners can be found in U.S. patent application Ser. No. 10/307,226, filed Nov. 29, 2002, which is incorporated herein by reference.  
         [0045]     B. Use of the Tissue Reinforcement Prosthesis  
         [0046]     The targeted region for deployment of the tissue reinforcement prosthesis  10  as just described can vary. For example, the targeted region can comprise a damaged or weakened area within a given body organ, as  FIG. 4  shows. In this embodiment, the presence of prosthesis  10  provides reinforcement to the body organ where damage or weakness exists.  
         [0047]     As another example (see  FIG. 5A ), the targeted region can comprise an aorta with an aneurysm. The use of a tissue reinforcement prosthesis  10  in this targeted region could be indicated, e.g., when the neck proximal to the aneurysm (i.e., closest to the head) is either too short or otherwise has a native anatomic feature that interferes with the secure placement of a conventional endovascular prosthesis to bridge the aneurysm. In this embodiment, the presence of prosthesis  10  provides reinforcement to the proximal neck of the aneurysmal aorta adjacent the renal arteries.  
         [0048]     When used for this purpose (see  FIG. 6A ), the reinforcement prosthesis  10  can also serve to anchor and support an auxiliary prosthesis structure  36  that, in the absence of the reinforcement prosthesis  10 , could not be deployed, due to native anatomic features of the vessel. In the illustrated embodiment, the auxiliary prosthesis structure  36  comprises an endovascular graft that, when deployed, bridges the aneurysm. Together, the reinforcement prosthesis  10  and the graft  36  form a prosthesis system  52 , as shown in  FIG. 6A .  
         [0049]     In this arrangement, the graft  36  includes a proximal end  38  that is sized and configured to be telescopically fitted within the lumen  18  of the trunk  12 . The lumen  18  of the trunk  12 , provides an interface region or socket  40  (see  FIG. 6B ) that is fully enclosed within the body of the trunk  12  itself. The lumen  18  is therefore not prone to kinking or twisting or other kinds of movement independent of the trunk  12 .  
         [0050]     It is desirable that the socket region  40  of the trunk  12  be specially sized and configured for the receipt and retention of the auxiliary graft  36 , e.g., by the use of folded-over materials to form multiple layers, and/or the use of denser weave patters or stronger fibers from, e.g., Kevlar™ material or Vectran™ material or metallic wire woven alone or interwoven with typical polyester fibers in the socket region  40 , additional stent rings, and the like, to reinforce the prosthesis in the socket region  40  where hooks or barbs  60  of the graft  36  can obtain purchase; and/or by the use of radiopaque markers  42  to fluoroscopically identify the socket region  40  on the prosthetic material  14 ; and/or the use of auxiliary stent rings on the inside of the prosthetic material  14  in the socket region  40  that interfere with exterior stent rings on the graft  36 , to resist migration of graft  36  from the prosthesis  10 .  
         [0051]     Being telescopically fitted within the socket region  40  (see  FIG. 6B ), and being also enclosed within the trunk  12  itself, the mechanical properties of the graft  36  are supplemented by the reinforcement, support, and integrity of the socket region  40  and trunk  12  themselves, and vice versa. Coupled together, the trunk  12  and the graft  36  provide enhanced resistance to migration and/or separation of the graft  36  from the trunk  12 . Seated within the enclosed socket region  40 , the graft  36  is peripherally sealed within the trunk  12  to resist leaks or seepage of fluids around the graft  36 .  
         [0052]     To enhance the fitment between the trunk  12  and the graft  36  within the socket region  40 , a mechanically interlocking relationship can be established. For example (as shown in  FIG. 6C ), a supplemental main stent ring  22 A on the interior of the socket region  40 —which would comprise the distal-most main stent ring of the trunk  12 —could be provided to mechanically engage or nest with a supplemental main stent ring  22 B on the exterior of the proximal end of the auxiliary prosthesis structure  36 . The mechanical interference between the supplemental stent rings  22 A and  22 B serves to capture the auxiliary prosthesis structure  36  within the trunk  12 , preventing both distal and proximal migration between the two prostheses  10  and  36 . It should also be appreciated that the inside-outside nesting relationship in the junction between the two prostheses  10  and  36  as described can be reversed, along with the reversal of the order of deployment; that is, the auxiliary prosthesis structure  36  can be deployed first, and the prosthesis  10  deployed second to nest within an end of the auxiliary prosthesis structure  36 , thereby elongating and reinforcing the neck region.  
         [0053]     In this arrangement (see  FIG. 5B ), the trunk  12  may include a supra-renal stent  44  at its proximal end, which extends beyond the prosthetic material  14 . When deployed within the aorta, this stent  44  would extend above the level of the renal arteries. The supra-renal stent  44  orients the prosthesis  10  within the lumen and aids in maintaining the position of the prosthesis  10  in the aorta without obstructing the normal blood flow into the renal arteries.  
         [0054]     During use (see  FIG. 7 ), a first catheter  20  is navigated over a guide wire  48  through an iliac to the desired location within the aorta near the renal arteries. The catheter  20  carries the reinforcement prosthesis  10  in a radially reduced configuration. At the targeted site, the catheter  20  releases the reinforcement prosthesis  10 , which expands radially into the position shown in  FIG. 5A . When the reinforcement prosthesis  10  ultimately serves to anchor an auxiliary graft  36 , the trunk  12  of the prosthesis  10  desirable extends distally from the proximal neck and partially into the aneurysm sac.  
         [0055]     A fastener assembly  34  is next deployed (see  FIG. 8 ) to place fasteners  28  into the end region  28  of the trunk  12 . The prosthesis  10  is thereby secured in position.  
         [0056]     The auxiliary graft  36  is carried in a radially compressed condition by another over-the-wire catheter  50  (see  FIG. 9 ). The catheter  50  deploys the graft  36 , such that the proximal end of the graft  36  is telescopically received within the socket region  40  of the trunk  12 . The prosthesis system  52  is thereby formed.  
         [heading-0057]     II. Other Prostheses  
         [0058]     A. Tubular Prosthesis for General Use  
         [0059]     Any given tubular prosthesis  54  (see  FIG. 10 ) can include a trunk  56  having a region  26  that is specially sized and configured for the receipt and retention of fasteners  28 , in the ways previously described. In  FIG. 10 , the trunk  56  is sized and configured to extend, for purposes of illustration, in the aorta adjacent the renal arteries distally to a location proximal the natural bifurcation of the iliac arteries. As shown in  FIG. 10 , the region  26  is located in the neck of the aorta adjacent to the renal arteries. The features of the region  26 , previously described, make possible the secure attachment of the prosthesis  54 , without migration.  
         [0060]     The prosthesis  54  desirable also includes other features of the prosthesis  10  already described, e.g., the main stent rings  22 , the end stent rings  24 , and the radiopaque markers  46 . The prosthesis  54  can also include a supra-renal stent  44  of the type shown in  FIG. 5B .  
         [0061]     B. Aorta Iliac Prosthesis  
         [0062]     As shown in  FIG. 11 , the trunk  58  of a given prosthesis  56  may be tapered, changing diameter from the proximal region to the distal region. In the embodiment shown in  FIG. 11 , the taper reduces the diameter of the trunk  58  in the proximal to distal direction. This taper direction is well suited for placement of the prosthesis  56 , at its proximal end, in the aorta adjacent the renal arteries and, at its distal end, in an iliac artery, as  FIG. 11  shows.  
         [0063]     The trunk  58  of the prosthesis  56  desirable also includes a region  26  that is specially sized and configured for the receipt and retention of fasteners  28 , in the ways previously described. As shown in  FIG. 11 , the region  26  is located in the neck of the aorta adjacent to the renal arteries. The features of the region  26 , previously described, make possible the secure attachment of the prosthesis  56 , without migration.  
         [0064]     The prosthesis  56  desirable also includes other features of the prosthesis  10  already described, e.g., the main stent rings  22 , the end stent rings  24 , and the radiopaque markers  46 . The prosthesis  54  can also include a supra-renal stent  44  of the type shown in  FIG. 5B .  
         [0065]     As described with respect to  FIGS. 10 and 11 , the targeted site of deployment is within the aorta adjacent the renal arteries. However, this targeted site of deployment is selected for purposes of illustrating the features of the prostheses  54  and  56 , and is not intended to be limiting.  
         [0066]     The preferred embodiments of the invention are described above in detail for the purpose of setting forth a complete disclosure and for the sake of explanation and clarity. Those skilled in the art will envision other modifications within the scope and sprit of the present disclosure.  
         [0067]     The above described embodiments of this invention are merely descriptive of its principles and are not to be limited. The scope of this invention instead shall be determined from the scope of the following claims, including their equivalents.