A cardiac-valve prosthesis, comprising: - an armature for anchorage of the valve prosthesis at an implantation site, said armature defining a lumen for passage of the blood flow; and - a set of prosthetic valve leaflets (3a, 3b, 3c), which are supported by said armature and are able to move, under the action of the blood flow, in a radially divaricated condition to enable the flow of the blood through said lumen in a first direction, and in a radially contracted condition, in which said valve leaflets (3a, 3b, 3c) co-operate with one another and block the flow of the blood through the prosthesis in the direction opposite to said first direction, wherein said armature comprises: - an inflow and an outflow annular parts connected by connection formations; - supporting formations for said set of leaflets, said formations being carried by at least one of said annular parts (20a, 20b) so as to leave substantially disengaged said lumen for passage of the blood; characterized in that: - said connection formations are anchorage formations, which extend as connection of said inflow and outflow annular parts (20a, 20b) with the capacity of projecting radially with respect to the prosthesis; - said connection formations are angularly distributed in three sets around the prosthesis so as to be able to extend into the sinuses of Valsalva; - said inflow annular part has a general flared pattern; and - a valve sleeve is provided having a base portion being arranged in a position of winding said flared inflow annular part. - an armature for anchorage of the valve prosthesis at an implantation site, said armature defining a lumen for passage of the blood flow; and - a set of prosthetic valve leaflets (3a, 3b, 3c), which are supported by said armature and are able to move, under the action of the blood flow, in a radially divaricated condition to enable the flow of the blood through said lumen in a first direction, and in a radially contracted condition, in which said valve leaflets (3a, 3b, 3c) co-operate with one another and block the flow of the blood through the prosthesis in the direction opposite to said first direction, wherein said armature comprises: - an inflow and an outflow annular parts connected by connection formations; - supporting formations for said set of leaflets, said formations being carried by at least one of said annular parts (20a, 20b) so as to leave substantially disengaged said lumen for passage of the blood; characterized in that: - said connection formations are anchorage formations, which extend as connection of said inflow and outflow annular parts (20a, 20b) with the capacity of projecting radially with respect to the prosthesis; - said connection formations are angularly distributed in three sets around the prosthesis so as to be able to extend into the sinuses of Valsalva; - said inflow annular part has a general flared pattern; and - a valve sleeve is provided having a base portion being arranged in a position of winding said flared inflow annular part. - an inflow and an outflow annular parts connected by connection formations; - supporting formations for said set of leaflets, said formations being carried by at least one of said annular parts (20a, 20b) so as to leave substantially disengaged said lumen for passage of the blood; characterized in that: - said connection formations are anchorage formations, which extend as connection of said inflow and outflow annular parts (20a, 20b) with the capacity of projecting radially with respect to the prosthesis; - said connection formations are angularly distributed in three sets around the prosthesis so as to be able to extend into the sinuses of Valsalva; - said inflow annular part has a general flared pattern; and - a valve sleeve is provided having a base portion being arranged in a position of winding said flared inflow annular part. - said connection formations are anchorage formations, which extend as connection of said inflow and outflow annular parts (20a, 20b) with the capacity of projecting radially with respect to the prosthesis; - said connection formations are angularly distributed in three sets around the prosthesis so as to be able to extend into the sinuses of Valsalva; - said inflow annular part has a general flared pattern; and - a valve sleeve is provided having a base portion being arranged in a position of winding said flared inflow annular part.