Patent ID: 8523934

Claim:
A method of treatment for a main vessel and a branch vessel branching from the main vessel, comprising: introducing a first prosthesis, having a first open end, a second open end, a lumen extending between the first and second open ends and a fenestration formed in a wall between the first and second open ends, into a main vessel and aligning the fenestration with an opening of the branch vessel; introducing a second prosthesis into the branch vessel, the second prosthesis having a proximal end, a proximal end opening, a distal end, a distal end opening, a body between the proximal and distal ends with a lumen therethrough, and a self-expanding anchor stent disposed at the proximal end opening, the anchor stent including a plurality of interconnected loops having a first loop end and a second loop end, the first loop end attached to the proximal end opening of the second prosthesis, the anchor stent expandable between a compressed state and an expanded state, in the expanded state the second loop end of the anchor stent extends radially away from the proximal end opening of the second prosthesis, and each loop has a curvature of between about 120 degrees and 200 degrees from a plane defined by the proximal end opening; inserting the second prosthesis through the fenestration of the first prosthesis; and expanding the anchor stent of the second prosthesis to the expanded state within the first prosthesis, such that the second loop ends contact an interior wall of the first prosthesis to anchor the second prosthesis to the first prosthesis.