An endoluminal prosthesis system for being deployed in a patient's aorta near the heart, includes a graft having a main body with a proximal end configured to be deployed near a patient's heart and a distal end configured to be deployed away from the patient's heart. The main body defines a proximal portion of the graft including the proximal end; a distal portion of the graft including the distal end; a middle portion of the graft extending between the proximal portion and the distal portion. A connection branch attached to the middle portion has an inner end attached to the middle portion and an outer end disposed radially outwardly from the inner end. The outer end of the connection branch includes a terminal ring composed of at least two partial rings pivotable relative to each other and including at least one radially outward barb.