Methods and apparatuses for regulating aortic regurgitation are provided. A catheter shaft is advanced through vasculature so that a flexible occluding membrane coupled to the catheter shaft is positioned within the aorta, typically the ascending aorta above the Sinus of Valsalva and coronary ostia. Blood flow in the aorta causes the flexible occluding membrane to alternate between an expanded occluding configuration while in diastole and a collapsed lesser occluding configuration is systole. The flexible occluding membrane thereby acts as a temporary aortic valve. The flexible occluding membrane is generally conical in shape, with the tip of the cone disposed closer to the aorta than the proximal rim. In diastole, blood flow expands the flexible occluding membrane so that the proximal rim apposes the inner wall of the aorta. The flexible occluding membrane will have one or more openings to allow perfusion of the coronary arteries in diastole.