An implantable prosthetic valve assembly includes a radially expandable frame including an inflow portion and a second portion. The inflow portion is configured, in an expanded state, to bear against a native cardiac annulus in a manner so as to resist migration. The second portion extends from the inflow zone in an outflow direction, and is configured, in an expanded state, not to bear against the native cardiac annulus and an ascending aorta. The valve assembly also includes a prosthetic valve coupled to the frame substantially within the second portion.