A prosthesis for implantation at an implantation site proximate a native aortic valve, the implantation site including a valve annulus and a plurality of Valsalva sinuses located distal to the valve annulus. The prosthesis comprises an armature and a valve connected to the armature, wherein the armature includes a proximal portion configured for anchorage to the valve annulus, a distal portion configured to be positioned distal to the Valsalva sinuses when the proximal portion is anchored to the valve annulus, and first, second and third Valsalva sinus anchors each extending between and connecting the proximal and distal portions and arching radially outward between the proximal portion and the distal portion. The Valsalva sinus anchors are positioned so that each can extend into and engage a wall of a different one of the Valsalva sinuses
