ABSTRACTThe first successful application of a transcatheter closure technique for patent ductus arteriosus (PDA) suitable for use in infants and children was performed by us in 1977. Since that time, there has been continued improvement and simplification of the equipment as well as in the implantation technique. Following a Food and Drug Administration protocol, a multicenter study was conducted to test the safety and effectiveness of this interventional method. The clinical results from three major regional test centers (Philadelphia, Houston, and New Haven) are presented. One hundred fortysix patients from a test population of 156 were treated for PDA with use of the Rashkind PDA Occluder Systems. Successful closure was accomplished in 94 (66%) of the total cases. Ten patients (7%) retained residual ductal murmurs despite correct placement of the occlusion devices; five additional patients (3%) were considered failures due to the presence of abnormal Doppler flow patterns after the procedure. Postrelease embolizations occurred in 19 (15%) instances. One patient required emergency surgical intervention after attempted retrieval of an embolized occluder. With the improvements in the manufacturing of the double-disk occluder systems as well as the perfection of the transvenous delivery technique, the incidences of closure failure and postrelease complications have decreased. Since January 1984, 78% of all transcatheter closure attempts were successful, with 10% embolization.