Sheath Capture Device for Stent Graft Delivery System and Method for Operating Same

Abstract

A delivery system for delivering and deploying stent grafts having a proximal stent includes a first lumen and a stent capture device including a capture portion fixedly connected adjacent a first lumen distal end. An outer catheter has a catheter distal end and a catheter inner diameter. A second lumen having a second distal end is slidably disposed about the first lumen and within the outer catheter. A stent graft sheath has a sheath proximal end connected to the second distal end and disposed about the first lumen. The sheath has a sheath distal end and a sheath inner diameter greater than the catheter inner diameter for holding a compressed stent graft. A distal nose cone has a cone proximal end connected to either the capture portion or the first distal end. The nose cone and the capture portion are movably adjustable to selectively capture the sheath distal end therebetween.

1 . A delivery system for delivering and deploying stent grafts having a proximal stent, the delivery system comprising:
 a hollow first lumen having a first distal end;   a stent capture device including a capture portion fixedly connected adjacent said first distal end;   a relatively rigid, hollow outer catheter having a catheter distal end and a catheter inner diameter;   a hollow second lumen having a second distal end and being slidably disposed about said first lumen and slidably disposed in said outer catheter;   a relatively flexible, hollow stent graft sheath having a sheath proximal end connected to said second distal end and disposed about said first lumen, said sheath having a sheath distal end and a sheath inner diameter greater than said catheter inner diameter to fit therein an at least partially compressed stent graft; and   a distal nose cone having a cone proximal end connected to at least one of said capture portion and said first distal end, said nose cone and said capture portion being movably adjustable to selectively capture said sheath distal end therebetween.   
     
     
         2 . The delivery system according to  claim 1 , wherein said nose cone and said capture portion define a cavity in which said sheath distal end is held releasably. 
     
     
         3 . The delivery system according to  claim 1 , further comprising a handle, said outer catheter defining a longitudinal axis and being longitudinally fixedly connected to said handle about said second lumen, said first and second lumens being longitudinally movably connected to said handle. 
     
     
         4 . The delivery system according to  claim 3 , wherein said outer catheter has a length only long enough to be inserted in a patient's aorta to approximately the patient's celiac axis. 
     
     
         5 . The delivery system according to  claim 1 , further comprising a hollow third lumen disposed about said first lumen and within said second lumen, said third lumen having a third distal end, said capture portion being a first capture portion, said stent capture device including a second capture portion fixedly connected adjacent said third distal end and selectively movable with respect to said first capture portion to capture a stent therebetween. 
     
     
         6 . A method of loading a stent graft in a prosthesis delivery system for implanting a stent graft in a patient at a treatment site, which comprises:
 providing a prosthesis delivery system including:
 a hollow first lumen having a first distal end; 
 a stent capture device including a capture portion fixedly connected adjacent the first distal end; 
 a relatively rigid, hollow outer catheter having a catheter distal end and a catheter inner diameter; and 
 a hollow second lumen having a second distal end and being slidably disposed about said first lumen and slidably disposed in said outer catheter; 
   loading a stent graft inside a relatively flexible, hollow stent graft sheath having a sheath inner diameter greater than said catheter inner diameter to temporarily dispose the stent graft therein in an at least partially compressed state, the stent graft sheath being disposed about said first lumen and having a sheath distal end and a sheath proximal end connected to said second distal end;   temporarily capturing a stent of the stent graft with the stent capture device;   removably capturing the sheath distal end between the capture portion and a distal nose cone having a proximal end connected to at least one of the capture portion and the first distal end; and   loading the sheath with the partially compressed stent graft into the outer catheter to compress the stent graft even further for subsequent implantation at the treatment site.   
     
     
         7 . The method according to  claim 6 , which further comprises carrying out the sheath capturing step by movably adjusting the nose cone and the capture portion to selectively secure the sheath distal end therebetween. 
     
     
         8 . The method according to  claim 6 , which further comprises:
 extending the outer catheter with the loaded sheath up to a given position at a distance from the treatment site; and   implanting the stent graft at the treatment site.   
     
     
         9 . The method according to  claim 8 , which further comprises carrying out the implantation step by:
 extending the first and second lumen in a patient towards the treatment site to move the sheath out from the outer catheter and return the stent graft to the partially compressed state in the sheath;   extending the first and second lumen further towards the treatment site to place the loaded sheath at the treatment site; and   releasing the sheath distal end from between the capture portion and the distal nose cone and unsheathing the stent graft from the sheath by retracting the second lumen away from the treatment site; and   releasing the stent from the capture device to implant the stent graft at the treatment site.   
     
     
         10 . The method according to  claim 6 , which further comprises:
 advancing the outer catheter in a patient towards a treatment site up to a given position at a distance from the treatment site;   while retaining the outer catheter in the given position:
 advancing the stent graft sheath out from the outer catheter to the treatment site to align the stent graft with the treatment site; 
 releasing the sheath distal end of the sheath from between the capture portion and the distal nose cone and unsheathing the stent graft from the sheath by retracting the second lumen away from the treatment site to at least partially implant the stent graft at the treatment site; 
   releasing the stent from the capture device to implant the stent graft at the treatment site; and   upon completion of the stent graft implantation, retracting both of the stent graft sheath and the outer catheter from the patient.   
     
     
         11 . The method according to  claim 10 , which further comprises carrying out the advancing step by advancing the sheath out from the outer catheter to the treatment site to axially align the stent graft with the treatment site and rotating the stent graft sheath to circumferentially align the stent graft with the treatment site. 
     
     
         12 . The method according to  claim 10 , which further comprises carrying out the advancing step by advancing the outer catheter towards the treatment site only up to a point at a distance from the treatment site greater than a length of the stent graft. 
     
     
         13 . The method according to  claim 10 , which further comprises carrying out the advancing step by advancing the outer catheter in vasculature of a patient towards a vascular treatment site. 
     
     
         14 . The method according to  claim 13 , which further comprises carrying out the advancing step by advancing the outer catheter in aortic vasculature of the patient to approximately a celiac axis of the patient. 
     
     
         15 . The method according to  claim 13 , which further comprises carrying out the advancing step by advancing the outer catheter in aortic vasculature of the patient to approximately a celiac axis of the patient. 
     
     
         16 . The method according to  claim 6 , which further comprises providing the outer catheter with a length sufficient to reach to approximately a celiac axis of a patient. 
     
     
         17 . The method according to  claim 6 , which further comprises providing the outer catheter with a length equal to approximately a distance from the patient's femoral arterial access site to the patient's celiac axis. 
     
     
         18 . The method according to  claim 10 , which further comprises carrying out the retracting step upon completion of the stent graft implantation by:
 retracting the stent graft sheath into the outer catheter; and   subsequently retracting the outer catheter containing the stent graft sheath from the patient.   
     
     
         19 . The method according to  claim 6 , which further comprises providing the stent graft sheath of a material relatively more flexible than a material of the outer catheter. 
     
     
         20 . A method of implanting a stent graft in a patient at a treatment site, which comprises:
 longitudinally locking a set of inner lumens and an inner sheath with respect to an outer lumen, at least a portion of the inner sheath constraining a stent graft;   capturing a distal end of the inner sheath between a stent capture device and a distal nose cone;   threading the lumens and the inner sheath onto a guidewire and into a patient to place the outer lumen into an aorta of the patient only up to a point at a distance from the treatment site greater than a length of the prosthesis;   longitudinally unlocking the inner lumens with respect to the outer lumen;   advancing the inner lumens and inner sheath distally out of the outer lumen in the aorta towards the patient's heart to transport the stent graft further upstream into the aorta;   unlocking the inner sheath constraining the stent graft from at least one interior lumen of the inner lumens; and   releasing the distal end of the inner sheath from between the capture portion and the distal nose cone by retracting the inner sheath in a proximal direction to at least partially implant the stent graft in a vessel.   
     
     
         21 . The method according to  claim 20 , which further comprises implanting the stent graft in the vessel at the treatment site by:
 retracting the second lumen away from the treatment site to unsheath the stent graft from the sheath; and   releasing the stent from the capture device.