title: The snare-assisted technique for transcatheter coil occlusion of moderate to large patent ductus arteriosus: immediate and intermediate results.
abstract: OBJECTIVE
  The purpose of this study was to evaluate the feasibility, safety and efficacy of using a snare-assisted technique to coil occlude the moderate to large size patent ductus arteriosus (PDA).
  
  
  BACKGROUND
  Transcatheter occlusion of small PDAs using Gianturco coils is safe and effective. However, in larger size PDAs and/or those with short PDA length, the procedure still carries risks of coil embolization, incomplete occlusion and failure to implant the coil.
  
  
  METHODS
  From January 1994 to June 1997, the records of 104 consecutive snare-assisted coil occlusions of moderate to large PDAs (minimum diameter >2.0 mm) were reviewed. Immediate and intermediate outcomes including complete and partial occlusion, failure to implant and complications were analyzed with respect to ductal type and size.
  
  
  RESULTS
  Patient age ranged from 0.1 to 70.1 years (median 3.3 years). Minimum PDA diameter ranged from 2.1 to 6.8 mm (mean 3.0 +/- 0.9 mm). Angiographic types were A-62, B-13, C-6, D-14 and E-9. Using the snare-assisted technique, coil placement was successful in 104/104 patients (100%), irrespective of size or angiographic type. Immediate complete closure was observed in 73/104 (70.2%) and was related to smaller PDA size, but not to angiographic type. Complete closure was documented in 102/104 (98.1%) at 2- to 16-month follow-up. Successful closure was unrelated to PDA size or type. Coil embolization to the pulmonary artery occurred in 3/104 (2.9%) patients and was not related to PDA size or type. The need for multiple coils was found in 28/104 patients (26.9%), and was related to larger PDA size, but not to angiographic type.
  
  
  CONCLUSIONS
  The snare-assisted delivery technique allows successful occlusion of moderate to large PDAs up to 6.8 mm, irrespective of angiographic type. This technique permits improved control and accuracy of coil placement, and facilitates delivery of multiple coils.
authors.affiliation: Department of Pediatric Cardiology, Baylor College of Medicine, Texas Children's Hospital, Houston, USA. fing@chsd.org
authors.forename: F F
authors.initials: FF
authors.lastname: Ing
authors.forename: R J
authors.initials: RJ
authors.lastname: Sommer
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D001027:Aortography; D006328:Cardiac Catheterization / Q000295:instrumentation*; D002648:Child; D002675:Child, Preschool; D004374:Ductus Arteriosus, Patent / Q000628:therapy*; D004621:Embolization, Therapeutic / Q000295:instrumentation*; D004867:Equipment Design; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D008875:Middle Aged; D019736:Prostheses and Implants; D016896:Treatment Outcome