of the above mentioned patent application publications to schwammenthal et al for other applications the shape of the valve does not cause such pressure recovery for example an angle between the pliant material 105 and a central longitudinal axis of prosthesis 10 may be too great to cause pressure recovery in this latter case the large angle may serve exclusively or at least in part to help provide axial fixation of prosthesis 10 to the native valve complex regardless of whether pressure recovery is achieved the angle between pliant material 105 and the central longitudinal axis of prosthesis 10 typically inhibits migration of the device in an upstream direction pliant material 105 comprises a flexible supple material such as an inert biological material e g pericardium sheet or any medically safe elastomer such as but not limited to polyester polymer a metallic material alloy polyurethane latex or synthetic rubber for some applications pliant material 105 is coupled to strut supports 20 and or inner struts 30 by sewing such as described hereinbelow with reference to fig4 for example pliant material 105 may be sewn onto outer diverging strut supports 20 valve 104 comprises a single piece or multiple pieces of pliant material 105 e g leaflets joined together.