Delivery System and Method for Self-Centering a Proximal End of a Stent Graft

Abstract

A method for implanting a prosthesis centrally within a curved lumen includes loading a prosthesis into a delivery sheath, advancing the sheath in a patient towards the curved lumen to place at least the proximal end of the prosthesis within the curved lumen, and centering the proximal end of the prosthesis and/or the distal end of the sheath within the curved lumen. In a first advancing step, the outer catheter containing the inner sheath is advanced together towards the curved lumen to a location proximal of the curved lumen and, in a second advancing step, the inner sheath containing the prosthesis is advanced into the curved lumen to place at least the proximal end within the curved lumen while the outer catheter substantially remains at the location. After centering, the proximal end of the prosthesis is deployed centered within the curved lumen.

1 . A method for implanting a prosthesis centrally within a curved lumen, which comprises:
 loading a prosthesis into a delivery sheath, the prosthesis having a proximal end and the sheath having a distal end;   advancing the sheath in a patient towards the curved lumen to place at least the proximal end within the curved lumen; and   centering at least one of:
 the proximal end of the prosthesis; and 
 the distal end of the sheath, 
   within the curved lumen.   
     
     
         2 . (canceled) 
     
     
         3 . (canceled) 
     
     
         4 . (canceled) 
     
     
         5 . The method according to  claim 1 , which further comprises carrying out the centering step by centering at least the distal end of the sheath within the curved lumen with a sheath centering device. 
     
     
         6 . The method according to  claim 5 , which further comprises:
 carrying out the loading step by partially collapsing the prosthesis to a size smaller than an interior of the sheath and inserting the partially collapsed prosthesis into the sheath; and   carrying out the deployment step by releasing the prosthesis centered within the curved lumen.   
     
     
         7 . The method according to  claim 1 , which further comprises:
 providing the sheath as a relatively flexible inner sheath; and   slidably disposing the inner sheath inside a relatively stiff outer catheter.   
     
     
         8 . The method according to  claim 7 , which further comprises carrying out the advancing step by:
 first advancing the outer catheter containing the inner sheath together towards the curved lumen to a location proximal of the curved lumen; and   subsequently advancing the inner sheath containing the prosthesis into the curved lumen while the outer catheter substantially remains at the location.   
     
     
         9 . The method according to  claim 1 , which further comprises carrying out the centering step within a curved portion of an aorta. 
     
     
         10 . The method according to  claim 1 , which further comprises:
 providing the prosthesis with a tubular graft body defining an inflow plane and an exit plane; and   providing all portions of the stents on the graft body between the inflow plane and the exit plane.   
     
     
         11 . The method according to  claim 1 , which further comprises:
 placing a guidewire through an implantation site within the curved lumen;   carrying out the advancing step by guiding the delivery sheath containing the prosthesis along the guidewire; and   carrying out the centering step by moving at least one of:
 the proximal end of the prosthesis; and 
 the distal end of the sheath, 
   in a direction away from the guidewire at the implantation site.   
     
     
         12 . The method according to  claim 1 , which further comprises providing a tip and carrying out the centering of the proximal end of the prosthesis with the tip. 
     
     
         13 . The method according to  claim 12 , which further comprises slidably disposing the tip within the delivery sheath. 
     
     
         14 . The method according to  claim 13 , which further comprises operatively connecting the tip to the delivery sheath to perform the centering step with the tip and the sheath. 
     
     
         15 . The method according to  claim 1 , which further comprises:
 slidably disposing a tip within the delivery sheath to place the tip at the distal end of the sheath;   connecting a sheath centering device to the tip through the sheath; and   carrying out the centering step with the sheath centering device.   
     
     
         16 . The method according to  claim 1 , which further comprises:
 providing a tip with a sheath centering device;   slidably disposing the tip within the delivery sheath to place the tip at the distal end of the sheath; and   carrying out the centering step by expanding the sheath centering device out from the tip.   
     
     
         17 . The method according to  claim 1 , which further comprises:
 providing a sheath centering device at the proximal end of the sheath; and   carrying out the centering step with the sheath centering device.   
     
     
         18 . The method according to  claim 1 , which further comprises carrying out the centering step with a sheath centering device physically separate from the sheath. 
     
     
         19 . (canceled) 
     
     
         20 . The method according to  claim 1 , which further comprises carrying out the centering step with a sheath centering device surrounding an exterior of the sheath. 
     
     
         21 . The method according to  claim 1 , which further comprises carrying out the centering step with a sheath centering device disposed between an exterior surface of the sheath and a wall of a lumen in which the sheath is present. 
     
     
         22 . The method according to  claim 1 , which further comprises carrying out the centering step with a sheath centering device disposed within the sheath. 
     
     
         23 . A method for centrally implanting a prosthesis, which comprises:
 placing at least a proximal end of a prosthesis in a curved lumen of a patient; and   centering the proximal end of the prosthesis within the curved lumen before implanting the prosthesis therein.   
     
     
         24 . A method for implanting a prosthesis centrally within a curved lumen, which comprises:
 loading a prosthesis into a delivery sheath, the prosthesis having a proximal end and the sheath having a distal end;   in a first advancing step, advancing the outer catheter containing the inner sheath together towards the curved lumen to a location proximal of the curved lumen; and   in a second advancing step, advancing the inner sheath containing the prosthesis into the curved lumen to place at least the proximal end within the curved lumen while the outer catheter substantially remains at the location;   centering at least one of:
 the proximal end of the prosthesis; and 
 the distal end of the sheath, 
   within the curved lumen; and   after carrying out the centering step, deploying the proximal end of the prosthesis centered within the curved lumen.   
     
     
         25 . A method of implanting a prosthesis in a patient at a treatment site, which comprises:
 providing a prosthesis delivery system with a relatively flexible inner sheath and a relatively stiff outer sheath;   loading a prosthesis inside the inner sheath;   loading the inner sheath containing the prosthesis within the outer sheath;   advancing the outer sheath in a patient towards the treatment site up to a given position at a distance from the treatment site;   while retaining the outer sheath in the given position:
 advancing the inner sheath out from the outer sheath to the treatment site to place at least a proximal end of inner sheath within the treatment site; and 
   centering at least one of:
 the proximal end of the prosthesis; and 
 a distal end of the inner sheath, 
   within the curved lumen;   retracting the inner sheath to at least partially implant the prosthesis at the treatment site; and   upon completion of prosthesis implantation, retracting both of the inner and outer sheaths from the patient.