In four female patients, aged 30, 10, 8 and 2 years and 9 months (the latter with Down's syndrome), all with a perimembranous ventricular septal defect (VSD), percutaneous closure of the VSD was carried out using an Amplatzer endoprosthesis. These were the first 4 patients to undergo this procedure in The Netherlands. In 3 of the patients the procedure was without complications and complete occlusion of the defects was achieved. The last patient developed a left anterior hemiblock after implantation of the device and one week later an intermittent second degree atrioventricular block was detected, for which a pacemaker was implanted. A few days later the atrioventricular conduction time returned to normal. There was complete occlusion of the defect. Percutaneous closure of a perimembranous VSD using an Amplatzer prosthesis is a promising technique with good short-term results. In a selected group of patients this new technique can replace surgical treatment.