The present invention relates to a prosthetic valve assembly for replacing a stenotic native aortic valve, comprising:a metallic frame having upper and lower extremities, said frame being collapsible to a compressed external diameter of 4.5 mm to 5.7 mm for advancement through an arterial introducer into a patients femoral artery using a catheterization technique, said frame being expandable to an expanded position for implantation within said stenotic native aortic valve, said lower extremity of said frame forming a zig-zag linea collapsible valvular structure sutured to said frame between said upper and lower extremities, said valvular structure formed of pericardial tissue for occluding blood flow in one direction andan internal cover made with the same tissue as said valvular structure, said internal cover having an upper end sutured to said valvular structure and a lower end sutured to said lower extremity of said frame along said zig-zag line, said internal cover sutured to a wall of said frame and extending along an internal surface of said wall of said frame only between said valvular structure and said lower extremity of said frame for preventing regurgitation of blood through said wall of said frame below said valvular structure.
