Abstract: Systems and methods for replacing defective heart valves are disclosed. The systems and methods include providing a valve with a tubular frame, a plurality of valve leaflets, and an expanding member. The expanding member has a collapsed and an expanded configuration. In a collapsed configuration, the expanding member can be disposed within a catheter so that the valve can be percutaneously positioned at the defective heart valve. In the expanded configuration, the expanding member can open to exert a force on one or more native valve leaflets. By exerting the force on the native valve leaflets, the expanding member can press the native valve leaflets away from a surface of the tubular frame. Pushing the native valve leaflets from the tubular frame enables blood flow through the tubular frame and decreases the risk of thrombosis between the valve leaflets and the tubular frame.