Valve incorporating at least one rocking flap with respect to elastic pivots

A valve for a valvular heart prosthesis comprising a ring member defining an opening having a first central axis extending centrally of said opening so as to be generally perpendicular to said ring member, at least one flap for selectively closing and opening said opening through said ring member, said flap having an outer periphery which is separate from said ring member, at least one elongated torsion member pivotally mounting said at least one flap to said ring member, said torsion member having inner and outer portions and an intermediate portion therebetween, said outer portion being fixedly secured to said ring member, said inner portion being spaced inwardly of the periphery of said flap, and being fixedly secured to said flap, said flap being pivotally moveable from a first position in which said flap extends generally across said opening defined by said ring member to thereby obstruct said opening to a second position generally parallel to said first axis thereof, said torsion member having a single elongated axis along said outer portion, said intermediate portion and said inner portion and exhibiting an elastic moment of force about said elongated axis when said intermediate portion is twisted about said elongated axis as said flap is pivoted relative to said ring member, said moment of force of said intermediate portion of said torsion member thereby urging said flap to return to said first position after said flap is pivoted therefrom.