title: Initial clinical experience in transcatheter closure of large patent arterial ducts in infants using the modified and angled Amplatzler duct occluder.
abstract: OBJECTIVE
  To establish the feasibility and efficacy of closing large patent arterial duct in infants, using the modified and angled variants of the Amplatzer duct occluder.
  
  
  BACKGROUND
  Closure of large patent arterial ducts by inserting devices in sick and underweight infants, particularly those weighing around 5 kilograms, remains a challenge. Bigger devices require larger delivery sheaths and may cause obstruction either to the aorta or left pulmonary artery. Negotiating a large device is difficult or impossible, as the sheath gets kinked. Because of these problems, such underweight infants with large ducts who are failing to thrive, and in left ventricular failure with associated lesions, are typically referred for surgery, often leading to higher morbidity and mortality.
  
  
  METHODS
  We attempted to close such large patent arterial ducts using the new Amplatzer occluder, modified with single layer of polyester, and the angled occluder, with no polyester material, inserted through a specially braided kink-resistant sheath.
  
  
  RESULTS
  Closure was achieved in 10 infants, with mean age of 8.2 months, mean weight of 5.5 kilograms, the lowest weighing 3.9 kilograms. The mean size of the patent ducts was 6.3 millimetres, with the largest measuring 8.6 millimetres. We implanted 6 modified and 4 angled occluders. In one patient, suffering from hydronephrosis, a 14/12 angled device embolized and was retrieved, but the patient died. In the remaining patients, all ducts were closed completely, with no obstruction to either the aorta or left pulmonary artery. On follow up, all showed excellent clinical improvement.
  
  
  CONCLUSIONS
  Complete closure of very large patent arterial ducts is now possible, even in very sick and underweight infants, using the large but low profile custom-made angled or modified versions of the Amplatzer occluder.
authors.affiliation: Department of Pediatric Cardiology, Children's Heart Care Centre, Sri Jayadeva Institute of Cardiology, Bangalore, Karnataka, India. dr_vj@hotmail.com
authors.forename: Ishwarappa B
authors.initials: IB
authors.lastname: Vijayalakshmi
authors.forename: Narasimhan
authors.initials: N
authors.lastname: Chitra
authors.forename: Ravindran
authors.initials: R
authors.lastname: Rajasri
authors.forename: Karthik
authors.initials: K
authors.lastname: Vasudevan
mesh_terms: D021721:Balloon Occlusion / Q000295:instrumentation*; D006328:Cardiac Catheterization / Q000295:instrumentation*; D004374:Ductus Arteriosus, Patent / Q000000981:diagnostic imaging / Q000628:therapy*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007223:Infant; D008297:Male; D011474:Prosthesis Design; D019919:Prosthesis Implantation / Q000295:instrumentation*; D011859:Radiography; D016896:Treatment Outcome