A prosthetic heart valve configured to replace a native heart valve and having a support frame configured to be reshaped into an expanded form in order to receive and/or support an expandable prosthetic heart valve therein. A dual-wireform support frame including an upper and a lower wireform permits expansion of the valve by one or two valve sizes, for example, with a 2-mm gap between each valve size. The lower wireform has a relatively shallow undulation so that it may stretch apart by a small amount and then prevent further expansion of the valve.