Abstract:
The present application provides a method of repairing a diseased vessel having a plurality of branch vessels extending therefrom. The method includes locating a vessel to removal from blood flow. A single incision is made to provide access to the vessel. Branch locating stent grafts having radio opaque edges are placed in a plurality of branch vessels branching from the located vessel. A single main vessel stent graft is placed in the vessel temporarily occlude the branch locating stent grafts that subsequently are located using the radio opaque edges. The surgeon punctures the wall of the main vessel stent graft at the edges to provide an access port from the main vessel stent graft to the branch locating stent grafts and finally places a plurality of branch connecting stents corresponding to each of the plurality of branch locating stent grafts.

Description:
CLAIM OF PRIORITY UNDER 35 U.S.C. §§119 AND 120 
     The present Application for Patent is a Continuation in Part and claims priority to patent application Ser. No. 10/643,554 entitled “VASCULAR STENT GRAFTS” filed Aug. 18, 2003, abandoned, which is hereby expressly incorporated by reference herein, which claims priority to Provisional Patent Applications Nos. 60/404,343 and 60/404,344, filed Aug. 19, 2002, entitled “MODULAR RECONSTRUCTABLE ENDOVASCULAR BYPASS STENT GRAFT” and “MODULAR RECONSTRUCTABLE STENT GRAFT” which are hereby expressly incorporated by reference herein. 
     REFERENCE TO CO-PENDING APPLICATIONS FOR PATENT 
     None. 
    
    
     BACKGROUND 
     1. Field 
     The technology of the present application relates to vascular surgery and, more particularly, a methodology for using vascular stents grafts in bypassing or removing portions of vascular anatomy from circulation and/or reconstructing vascular anatomy. 
     2. Background 
     The circulatory system comprises many different parts, one of which is the vascular system. Blood vessels can develop various problems, diseases, or other pathology that frequently requires surgical repair. 
     Two common conditions include vascular blockage, such as, for example, blood clots, and aneurysms. Blockage is generally repaired surgically by, for example, bypass surgery, a balloon catheter, or the like. Surgeons conventionally treat aneurysms by surgically removing the aneurysm. Some aneurysms can be treated using endovascular methodologies including placing a stent graft, but frequently endovascular treatment using a stent graft is not possible because branch vessels become occluded. These and other conventional procedures for correcting vascular pathology are not particularly satisfactory. Thus, it would be desirous to develop apparatuses and methods that allowed for endovascular repair of the vascular system. 
     SUMMARY 
     To attain the advantages and in accordance with the purpose of the invention, as embodied and broadly described herein, methods to facilitate endovascular repair of a diseased vessel are provided. In particular, the method comprises locating a main vessel of the endovascular system that requires repair. Making a single incision to allow access to the main vessel. Placing a branch locating stent graft having a radio opaque marker in a branch vessel located off of a main vessel. Placing a main vessel stent graft in the located main vessel such that the branch locating stent graft is occluded. Locating the branch locating stent graft using the radio opaque marker. Puncturing a wall of the main vessel stent graft at the located radio opaque marker to provide an access port from the main vessel stent graft to the branch locating stent graft and providing a branch connecting stent from the main vessel stent graft to the branch locating stent graft such that the main vessel stent graft, the branch connecting stent, and the branch locating stent graft are in fluid communication. 
     The foregoing and other features, utilities, and advantages of the technology of the present application will be apparent from the following more particular description of exemplary embodiments as illustrated in the accompanying drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments of the technology of the present application, and together with the descriptions, serve to explain the principles thereof. Like items in the drawings may be referred to using the same numerical reference. 
         FIG. 1  shows a portion of a vascular anatomy with an endovascular stent graft consistent with the technology of the present application; 
         FIG. 2  shows devices useful for placement of the endovascular stent graft of  FIG. 1 ; 
         FIG. 3  shows puncturing a main vessel stent graft consistent with establishing a working port; 
         FIG. 4  shows a cross-sectional view of an access port and bypass stent graft consistent with an embodiment of the technology of the present application; 
         FIG. 5  shows a portion of a vascular anatomy with an endovascular stent graft consistent with another embodiment of the technology of the present application; 
         FIG. 6  shows puncturing a main vessel stent graft consistent with establishing a working port; 
         FIG. 7  shows a portion of a vascular anatomy with an endovascular stent graft consistent with another embodiment of the technology of the present application; 
         FIG. 8  shows another construction of main vessel stent graft; and 
         FIG. 9  shows an illustrative flow chart describing a method of implanting stents consistent with the technology of the present application. 
     
    
    
     DETAILED DESCRIPTION 
     Some embodiments of the present invention are described with reference to  FIGS. 1 to 9 . The embodiments are described with reference to exemplary embodiments thereof. The word “exemplary” is used herein to mean “serving as an example, instance, or illustration.” Any embodiment described herein as “exemplary” is not necessarily to be construed as preferred or advantageous over other embodiments. Moreover, unless otherwise stated, all embodiments described herein should be construed as exemplary. 
     Referring first to  FIG. 1 , a cut-away portion of a blood vessel  100  is shown. A clot  102 , blockage, or other vascular pathology in blood vessel  100  requires a bypass. An endovascular bypass stent graft  104  is shown implanted in blood vessel  100 . Endovascular bypass stent graft  104  comprises a main vessel stent graft  106  and a bypass stent graft  108 . Main vessel stent graft  106  has an access port  110  located proximate clot  102 . Bypass stent graft  108  has a proximate end  112  and a distal end  114 . Proximate end  112  is connected to access port  110  in a sealing relationship, which will be explained further below with respect to  FIG. 4 . Distal end  114  resides within vessel  100  such that bypass stent graft  108  bypasses clot  102  or other vascular pathology. 
     Implanting or deploying endovascular bypass stent graft  104  will be explained with reference to  FIG. 2 . First a main deployment catheter  202  and main vessel stent graft  106  are guided to clot  102  using standard endovascular surgical techniques. Main deployment catheter  202  comprises a proximate balloon  204 , a distal balloon  206 , and a working port  208 . Inflating proximate balloon  204  and distal balloon  206  isolates working port  208  from blood flow. 
     Referring now to  FIG. 3 , a trocar  302  is passed through the main deployment catheter  202  and out working port  208  once balloons  204  and  206  isolate blood flow. Using 3-D navigational technology (as is commonly available in the art), trocar  302  is aligned with working port  208  and used to puncture main blood vessel  100  about working port  208 . As shown in  FIG. 3 , main vessel stent graft  106  may be deployed without an access port  110 . In this case, trocar  302  first punctures main vessel stent graft  106  to make the access port  110 . When the access port  110  in main vessel stent graft  106  is made by trocar  302 , main vessel stent graft  106  is designed to form a controlled tear pattern, such as a controlled stellate pattern  304 , as is commonly known in the art. 
     Once blood vessel  100  is punctured, a bypass catheter  210  is passed to the vascular pathology and through working port  208  to access port  110 . Bypass catheter  210  comprises a dissecting balloon  212  and a tool port  214  at the distal end thereof. A wire needle  216  is passed out tool port  214 . Using the bypass catheter  210 , dissecting balloon  212  and wire needle  216  pass through the working port  208 , access port  110 , and the puncture of blood vessel  100  and enters the perivascular space about blood vessel  100 . The dissecting balloon dissects the perivascular space up to a vessel re-entry port  218 . Vessel re-entry port  218  is shown as a part of blood vessel  100  such that clot  102  is removed from circulation, but vessel re-entry port  218  could reside in a separate blood vessel (not specifically shown) as required by the patient&#39;s anatomy and the particular pathology involved. Wire needle  216  punctures the vessel to establish re-entry port  218 . 
     Once wire needle  216  establishes re-entry port  218 , bypass catheter  210  is removed and bypass stent graft  108  is passed over wire needle  216 . Distal end  114  is placed in the vessel at re-entry port  218  and expanded to fit snuggly with the vessel wall in a sealing relationship. Bypass stent graft  108  could be expanded using a balloon or made out of an expanding material, such as, for example, shape memory alloys. The proximate end  112  and access port  110  are joined in a sealing relationship, as explained below. 
     Once bypass stem graft  108  is placed, proximate balloon  204  is deflated and blood flow is verified. Finally, distal balloon  206  is deflated and the catheter is removed leaving endovascular bypass stent graft  104  in place. 
       FIG. 4  shows the sealing relationship between access port  110  and proximate end  112  in more detail. In particular, a cross-sectional view of access port  110  and proximate end  112  is shown. Access port  110  has an edge  402  defining access port  110 . About edge  402  is a seating surface  404 . Proximate end  112  has a corresponding engaging surface  406 . Engaging surface  406  mates with seating surface  404  to forma seal that inhibits blood leakage. Reference number  408  is a material that further inhibits bleeding or leakage. Reference number  408  could be a sealing ring, such as a GORTEX® washer, that could be deployed between seating surface  404  and engaging surface  406  to further inhibit blood flow. Alternatively, reference number  408  could be a form of epoxy, acrylic, silicone, tape, glue, or resin that seals seating surface  404  and engaging surface  406 . Still further, bypass stent graft  108  and/or main vessel stent graft  102  could be constructed out of shape memory alloys, such as, for example, Ag—Cd alloys, Cu—Al—Ni alloys, Cu—Sn alloys, Cu—Zn alloys, Cu—Zn—Si alloys, Cu—Zn—Sn alloys, Cu—Zn—Al alloys, In—Ti alloys, Ni—Al alloys, Ni—Ti alloys, Fe—Pt alloys, Mn—Cu alloys, Fe—Mn—Si alloys, and the like. These could be designed such that seating surface  404  and engaging surface  406  form an adequate seal and then deformed for deployment. After deployment, an activation signal could cause seating surface  404  and engaging surface  406  to join in a sealing relationship. The activation signal could be a thermal, electrical, magnetic, radiation signal or the like. Notice, the seal between access port  110  and bypass stem graft  108  could be accomplished using a branch connecting stent. Branch connecting stents are explained further below with reference to  FIG. 7 . 
     Referring now to  FIG. 5 , another embodiment of the present invention is shown.  FIG. 5  shows a cut-away portion of a blood vessel  500 . In this case, blood vessel  500  contains a type of aneurysm  502  or other vascular pathology that needs to be isolated from blood vessel  500 . As shown, blood vessel  500  has branch vessels  504  that prevent the use of a conventional stent because a conventional stent would occlude blood flow to branch vessels  504  indefinitely. In this case, endovascular stent graft  506  includes a main vessel stent graft  508  and a number of branch connecting stents  510 ,  510   y . Branch connecting stent  510   y  is similar to branch connecting stent  510 , but is distinguished to illustrate the use of a Y shaped main vessel stent  800  in place of main vessel stent  508  as is explained further below in connection with  FIG. 8 . In this case, two branch connecting stents  510  and  510   y  are shown, but more or less could be deployed as necessitated by patient anatomy. Branch connecting stents  510 ,  510   y  connect through access ports  512 ,  512   y  to main vessel stent graft  508  such that distal ends  514 ,  514   y  of branch connecting stems  510 ,  510   y  reside in branch vessels  504  and proximate ends  516 ,  516   y  of branch connecting stents  510 ,  510   y  are in a sealing relationship with access ports  512 ,  512   y , such sealing relationship is further explained in connection with  FIGS. 4 and 7 . 
     Endovascular stent graft  506  can be deployed in a number of different ways. For example, main vessel stent graft  508  can be placed using conventional endovascular techniques. Once placed, using 3-D surgical navigation techniques, commonly known in the art, a trocar  602  is used to puncture main vessel stent graft  508  at the junction with branch vessel  504  (See  FIG. 6 ). Main vessel stent graft  508  is constructed such that trocar  602  would from a controlled tear  604 , such as a controlled stellate pattern. A balloon  606  would be used to dilate tear  604  to a size capable of accepting branch connecting stents  510 ,  510   y . Branch connecting stents  510 ,  510   y  are then passed to the site such that distal ends  514 ,  514   y  reside in branch vessels  504  and proximate ends  516 ,  516   y  form a sealing relationship with access ports  512 ,  512   y.    
     While main vessel stent graft  508  (and main vessel stent graft  106 ) is shown as a tubular member conforming to the shape of the vessel  500  (or  100 ), main vessel stent graft  508  could be other shapes, such as, for example, a y shaped main vessel stent graft  800 . In this case, y branch  802  would replace branch connecting stent  510   y  ( FIG. 5 ) as well as remove the need for access port  512   y . Other shapes are possible. 
       FIG. 7  shows placing branch locating stent graft  702 . Branch locating stent graft  702  would have a radiopaque edge  704  proximate vessel  500 . Main vessel stent graft  508  would be passed to the vascular site occluding branch vessels  504  and branch locating stent graft  702 . Trocar  604  would then be aligned with radio opaque edge  704  using 3D surgical navigation as is commonly understood in the art or some other conventional mechanism and main vessel stent graft  508  would be punctured to form access port  512 . A branch connecting stent  706  would then be placed such that a distal end  708  of branch connecting stent  706  resided in and formed a sealing relationship with branch locating stent graft  702  and a proximate end  710  of branch connecting stent  706  resides in and forms a sealing relationship with access port  512  of main vessel stent graft  508 . 
     Referring now to  FIG. 9 , a flowchart  900  is provided illustrating an exemplary methodology associated with one or more of the stents described above. First, a surgeon would locate or identify a portion of the vascular system that required repair or removal from blood flow, step  902 . For example, blood vessel  500  has aneurysm  502 , see  FIG. 5 , or the like is identified by the surgeon. Next, a single incision is made in the endovascular system to provide surgical access to the blood vessel  500 , step  904 . For example, an incision  550  may be made in blood vessel  500 , see  FIG. 5 . Using conventional surgical techniques, such as, for example, inserting a catheter through incision  550  to branch vessels, branch locating stents grafts  702  are placed in branch vessels  504  through the incision  550 . Branch locating stents grafts are provided with radio opaque edges  704 , step  906 . Main vessel stem graft  508  is placed through the incision  550 , step  908 , following placement of branch locating stents grafts  702  using conventional surgical techniques. Main vessel stent graft  508  occludes branch locating stent grafts  702 . Using surgical navigation equipment to locate the radio opaque edges, a trocar, or the like, punctures the wall of main vessel stent graft  508  to provide the access port  512  on the wall, steps  909  and  910 . A branch connecting stent  706  is then provided to provide fluid communication between main vessel stent graft  508 , branch connecting stent  706 , and branch locating stents graft  702 , step  912 . Subsequently, the tools are removed and the incision closed, step  914 . 
     The previous description of the disclosed embodiments is provided to enable any person skilled in the art to make or use the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other embodiments without departing from the spirit or scope of the invention. Thus, the present invention is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.