Six days old neonate with pulmonary atresia and intact ventricular septum is reported in which a communication was established between the right ventricle and the pulmonary artery. The membraneous atresia was perforated with a special radiofrequency catheter 2F connected to a Hat 200S radiofrequency generator (Osypka). The energy necessary to perforation was 15W. After perforation of the atresia, balloon dilation was performed (balloon diameter: 2, 3, 4mm of coronary angioplasty and 5, 8mm Penta Medi-tech). The valve was completely opened giving the continuity between right ventricle and pulmonary artery.