A transcatheter occluding intracardiac defect device comprises a folding poly-urethane foam with Teflon coated wire skeleton, introducible into a long vascular sheath and automatically unfolded upon delivery in the distal to the defect cardiac chamber. A two mm string loop is attached to the center of the occluder, while the loop is closed by a 1 mm knot. A loading wire comprises a Teflon hollow wire and a double mono-filament thread which carries the occluder on the one end and is tied on the other end. An occluder-holder comprises a rhomboid poly-urethane foam with Teflon coated wire skeleton and a "rubber" piece sutured in the center. The occluder-holder is advanced over the loading wire axis and through the long sheath in the proximal to the defect cardiac chamber and is pushed against the occluder till it is securely buttoned. The distal end of the loading wire is cut and the hollow wire is pulled out over the double thread. The thread is pulled as a single strand and therefore the device is released.