Branch endograft delivery

Abstract

A system for treating disease involving branching vessels of a mammal is provide. The system may include a main graft assembly (i) having a lumen permitting fluid flow therethrough, and (ii) configured to expand within, and contact a wall of, a first vessel of a mammal; and a branch graft assembly including a branch cover (i) having a cover lumen permitting fluid flow therethrough; and (ii) configured to expand within, and contact a wall of, a branch vessel that branches from the first vessel. The branch graft assembly may also include an expandable branch stent extending within the cover lumen. The branch graft assembly may further include a branch sheath (i) extending between the branch stent and the cover lumen, and (ii) constraining radial expansion of the branch stent within the cover lumen.

1 . A system for treating disease involving branching vessels of a mammal, comprising:
 a main graft assembly (i) having a lumen permitting fluid flow therethrough, and (ii) configured to expand within, and contact a wall of, a first vessel of a mammal; and   a branch graft assembly comprising:
 a branch cover (i) having a lumen (cover lumen) permitting fluid flow therethrough; and (ii) configured to expand within, and contact a wall of, a branch vessel that branches from the first vessel; 
 an expandable stent (branch stent) extending within the cover lumen; and 
 a branch sheath (i) extending between the branch stent and the cover lumen, and (ii) constraining radial expansion of the branch stent within the cover lumen. 
   
     
     
         2 . The system of  claim 1 , wherein the branch sheath at least partially surrounds the branch stent. 
     
     
         3 . The system of  claim 1 , wherein distal movement of the branch sheath within the branch cover is inhibited by a coupling of the branch stent to the branch cover. 
     
     
         4 . The system of  claim 3 , wherein the coupling is of a distal portion of the branch stent to a distal portion of the cover. 
     
     
         5 . The system of  claim 1 , further comprising a delivery catheter (a) configured to be placed into the first vessel and (b) through which the main graft assembly is configured to extend. 
     
     
         6 . The system of  claim 5 , wherein the branch sheath extends through both an aperture in the catheter and an aperture in the main graft assembly. 
     
     
         7 . The system of  claim 5 , wherein the branch sheath extends through an aperture in the catheter. 
     
     
         8 . The system of  claim 1 , wherein the branch sheath extends within the main graft assembly and into the branch cover through an aperture in the main graft assembly. 
     
     
         9 . The system of  claim 1 , wherein the branch stent is configured to expand radially against the branch cover upon release of the branch stent from the branch sheath by proximal movement of the branch sheath. 
     
     
         10 . The system of  claim 1 , wherein the main graft assembly and the branch graft assembly are configured to lie substantially parallel to each other during delivery of the main graft assembly to the first vessel, and wherein the branch graft assembly is configured such that, while a proximal portion of the assembly remains within and/or in contact with the main graft assembly, the distal portion of the assembly moves away from the main graft assembly when the assembly is unconstrained by a sheath during delivery of the branch cover to the branch vessel. 
     
     
         11 . The system of  claim 1 , further comprising an elongate member (branch delivery member) configured to extend through the branch cover and into the branch vessel. 
     
     
         12 . The system of  claim 11 , further comprising an anchoring member, at a distal portion of the branch delivery member, that expands in and engages the branch vessel to resist axial movement of the anchoring member within the branch vessel. 
     
     
         13 . The system of  claim 1 , wherein each of the first vessel and the branch vessel comprises an artery or a vein. 
     
     
         14 . The system of  claim 1 , wherein the main graft assembly comprises (a) a main stent that is expandable and (b) a main cover that at least partially surrounds the main stent. 
     
     
         15 . The system of  claim 14 , wherein the a main cover is coextensive with the branch cover. 
     
     
         16 . The system of  claim 12 , wherein the anchoring member self-expands upon release of the anchoring member from a lumen of a constraining member, by proximal movement of the constraining member relative to the anchoring member. 
     
     
         17 . A method, of treating disease involving branching blood vessels of a mammal, comprising:
 advancing distally into a first blood vessel of a mammal a main stent graft having a lumen permitting fluid flow therethrough;   expanding the main stent graft within, and contacting a wall of, the first vessel;   advancing through the first vessel, and into a branch vessel that branches from the first vessel, a branch graft assembly comprising:
 a branch cover (i) having a lumen (cover lumen) permitting fluid flow therethrough; 
 an expandable stent (branch stent) extending within the cover lumen; and 
 a branch sheath (i) extending between branch stent and the cover lumen, and (ii) constraining radial expansion of the branch stent within the cover lumen; 
   releasing the branch stent from within the branch sheath, thereby permitting expansion of the branch stent and branch cover such that the branch cover contacts a wall of the branch vessel.   
     
     
         18 . The method of  claim 17 , wherein the branch sheath at least partially surrounds the branch stent. 
     
     
         19 . The method of  claim 17 , wherein the releasing comprises moving the branch sheath proximally. 
     
     
         20 . The method of  claim 19 , wherein the advancing of the main stent graft, the advancing of the branch graft assembly, and withdrawing of the branch sheath from the mammal after the releasing all occur through a single opening in skin of the mammal.