Biologically implantable prosthesis and methods of using the same

A method of replacing a prosthetic valve comprising:

• disengaging a first engagement element of a first prosthesis with a second engagement element of a second prosthesis to uncouple the second prosthesis from the first prosthesis, wherein the first prosthesis is implanted in a native annulus, and wherein the second prosthesis comprises a prosthetic valve;
• wherein disengaging the first engagement element with the second engagement element to uncouple the second prosthesis from the first prosthesis comprises deforming the second prosthesis such that the second engagement element disengages the first engagement element;
• wherein deforming the second prosthesis comprises inserting a lever into a gap between the second prosthesis and the first prosthesis, the gap being defined by a scallop separating two lobes in a latitudinal cross-section in a plane perpendicular to a central longitudinal axis of the first prosthesis, the scallop being disposed closer to the central longitudinal axis within the plane than the two lobes, and applying a force to the second prosthesis with the lever to deform the second prosthesis such that the second engagement element disengages the first engagement element;
• and
• engaging a third engagement element of a third prosthesis with the first engagement element of the first prosthesis to securely couple the third prosthesis to the first prosthesis, wherein the third prosthesis comprises a prosthetic valve.