Abstract: An occluder for a prosthetic heart valve assembly adapted within a seating-ring passage having a body including a downstream sealing section comprising a plurality of cuspids which engage each other to define a closed sealing section when the occluder is in its closed position and which flex outwardly relative to each other when the occluder is in its open position to define a central open passage through the occluder, and an armature reinforcing the body. The armature includes an annular ring and a plurality of reinforcing arms hingedly connected to the ring and extending through each cuspid to permit flexure of each arm relative to the annular ring.