A barbed medical prosthesis (10) is disclosed in which the barb (11) includes a basal portion (13) comprising a point of union (19) with the substrate of origin (15) (such as a strut), an anchoring portion (12) adapted to embed into tissue, and a stress-dispersing portion (14) located between the basal and anchoring portions. In one embodiment the stress-dispersing portion comprises a helical coil (38) having a free winding (20) that is unattached to the strut from which the barb extends. In another embodiment, the stress-dispersing portion comprises a series of bends or curves (24) formed in the barb proximate to the point of union with the strut. The barb can be mechanically attached and/or soldered to the prosthesis, or integrally formed therefrom. A second barb portion (37) and stress-dispersing portion, may also extend from the basal portion.