title: Various reasons for repeat dilatation of stented pulmonary arteries in paediatric patients.
abstract: OBJECTIVE
  To evaluate the reasons for repeat intervention in patients treated with balloon expandable stents for pulmonary artery stenoses, with particular analysis of the time intervals between interventions.
  
  
  METHODS
  A retrospective observational study.
  
  
  METHODS
  A single paediatric cardiology centre.
  
  
  METHODS
  38 patients, mean age 6.9 years, range 6 days to 34 years (one adult patient); mean weight 19.7 kg, range 2.5-75 kg.
  
  
  METHODS
  Implantation of balloon expandable stents in 46 cases of main pulmonary artery stenosis, right pulmonary artery stenosis, left pulmonary artery stenosis, or right ventricle to pulmonary artery conduits.
  
  
  METHODS
  Adaptation of stent diameter to patient growth; development of pulmonary arteries; pressure gradient in the right ventricle.
  
  
  RESULTS
  56 stents were implanted in 46 lesions. During a mean follow up time of 2.2 years, 40 repeat dilatations were performed on 28 of 42 reinvestigated stents. A second repeat dilatation was performed on eight stents, and a third on four stents. The mean time period between implantation and repeat dilatations was 15.5 months.
  
  
  CONCLUSIONS
  Repeat dilatation of stented pulmonary arteries was done mainly to adapt the stent diameter to the patient's growth. However, repeat dilatations were also performed to relieve stent obstruction caused by intimal proliferation (17.5%), or to overcome progressive external compression (25%). While most repeat interventions in adult patients are for intimal hyperplasia, in paediatric patients they are needed for a variety of reasons.
authors.affiliation: Department of Paediatric Cardiology, Charité Medical Centre, Humboldt University, Berlin, Germany. martin.schneider@charite.de
authors.forename: M B E
authors.initials: MB
authors.lastname: Schneider
authors.forename: P
authors.initials: P
authors.lastname: Zartner
authors.forename: K
authors.initials: K
authors.lastname: Duveneck
authors.forename: P E
authors.initials: PE
authors.lastname: Lange
mesh_terms: D000208:Acute Disease; D000293:Adolescent; D000328:Adult; D002404:Catheterization / Q000379:methods*; D002648:Child; D002675:Child, Preschool; D002908:Chronic Disease; D003251:Constriction, Pathologic / Q000000981:diagnostic imaging / Q000628:therapy; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D011475:Prosthesis Failure; D011651:Pulmonary Artery / Q000002:abnormalities* / Q000000981:diagnostic imaging; D011859:Radiography; D012008:Recurrence; D012086:Reoperation; D015607:Stents / Q000009:adverse effects; D013997:Time Factors