title: Transcatheter management of residual shunts after initial transcatheter closure of a patent arterial duct.
abstract: OBJECTIVE
  To assess the efficacy and safety of transcatheter reocclusion of persistent leaks following previously attempted transcatheter occlusion of persistent arterial duct.
  
  
  METHODS
  Retrospective study.
  
  
  METHODS
  Tertiary pediatric cardiology centre.
  
  
  METHODS
  From February 1987 through October 1996, trans-catheter occlusion of a residual ductal shunt was attempted in 42 consecutive patients at a median age of 5.0 years (range 1.6 years to 16.2 years).
  
  
  METHODS
  Fourty patients had successful placement of a double umbrella occluder (n=27) or coils (n=13) across residual shunts. Complications included device embolization in two patients and hemolysis in one patient.
  
  
  RESULTS
  Mean z-score for left ventricular end-diastolic dimension (LVEDD) at initial echocardiography was +2.55 +/- 1.89 (P<0.0001 versus normal); z-score for left pulmonary artery (LPA) diameter was +2.00 +/- 1.52 (P<0.0001). Mean LPA to right pulmonary artery (RPA) diameter ratio was 1.05 +/- 0.18. At follow-up echocardiogram, a median of two years (range six months to 7.7 years) after the second procedure, a shunt was persistent in 3% of the patients. Mean LVEDD and LPA diameter z-value, and mean LPA to RPA diameter had dropped significantly to +0.42 +/- 1.31, +0.07 +/- 1.15 and 0.86 +/- 0.14 (P<0.001), respectively. LPA flow acceleration was present in 25% of patients. Three of nine patients, in whom lung perfusion scan was performed, had left lung perfusion below 40%. Small weight and age at catheterization were significant risk factors for LPA flow disturbance.
  
  
  CONCLUSIONS
  Repeat transcatheter occlusion is safe and successful in eliminating residual shunt across the arterial duct. Attention should, however, be addressed to the potential for LPA stenosis and growth, and flow should be regularly assessed.
authors.affiliation: Department of Pediatrics, The Hospital for Sick Children, The University of Toronto School of Medicine, Toronto, Ontario, Canada.
authors.forename: C
authors.initials: C
authors.lastname: Ovaert
authors.forename: B W
authors.initials: BW
authors.lastname: McCrindle
authors.forename: D
authors.initials: D
authors.lastname: Nykanen
authors.forename: R M
authors.initials: RM
authors.lastname: Freedom
authors.forename: L N
authors.initials: LN
authors.lastname: Benson
mesh_terms: D000293:Adolescent; D001783:Blood Flow Velocity; D002404:Catheterization / Q000009:adverse effects; D002648:Child; D002675:Child, Preschool; D004374:Ductus Arteriosus, Patent / Q000000981:diagnostic imaging / Q000503:physiopathology / Q000628:therapy*; D004452:Echocardiography; D004621:Embolization, Therapeutic; D005260:Female; D006801:Humans; D007223:Infant; D008297:Male; D011651:Pulmonary Artery / Q000000981:diagnostic imaging; D019233:Retreatment; D012189:Retrospective Studies