An instrument for attaching a graft to an aorta includes a first needle assembly for breaching the aorta to provide a hole in a wall thereof, and a carrier portion for insertion of an end of a tubular graft through the hole and into the aorta. Arms are pivotally mounted on the instrument and are moveable from a position extending axially of the carrier to a position extending radially from the carrier to spread the end of the graft radially outwardly from a tubular portion of the graft to form an annular flange extending outwardly from the tubular portion, and to support the flange within the aorta and around the hole therein. A second needle assembly retains the suture material and advances the suture material into engagement with the aorta wall and the graft flange for suturing the graft flange to the aorta wall.