title: Short- and long-term effects of inhaled iloprost therapy in children with pulmonary arterial hypertension.
abstract: OBJECTIVE
  This study investigated the short- and long-term outcome of children with pulmonary arterial hypertension (PAH) treated with inhaled iloprost.
  
  
  BACKGROUND
  Inhaled iloprost has been approved for the treatment of adults with PAH, but little is known about the effects in children with PAH.
  
  
  METHODS
  We evaluated the acute effects of inhaled iloprost on hemodynamic status and lung function and the response to long-term therapy in 22 children (range 4.5 to 17.7 years) with PAH (idiopathic, n = 12; congenital heart disease, n = 10). Cardiac catheterization, standard lung function testing before and after iloprost inhalation, 6-min walk test, World Health Organization functional class, and hemodynamic parameters were monitored.
  
  
  RESULTS
  Acute administration of inhaled iloprost lowered mean pulmonary artery pressure equivalent to the response to inhaled nitric oxide with oxygen. Acute iloprost inhalation reduced forced expiratory volume in 1 s and mid-volume forced expiratory flow by 5% and 10%, respectively, consistent with acute bronchoconstriction. At 6 months, functional class improved in 35%, decreased in 15%, and remained unchanged in 50% of children. Sixty-four percent of patients continued receiving long-term iloprost therapy, 36% stopped iloprost, due to lower airway reactivity, clinical deterioration, or death. In 9 patients on chronic intravenous prostanoids, 8 transitioned from intravenous prostanoids to inhaled iloprost, which continued during follow-up.
  
  
  CONCLUSIONS
  Inhaled iloprost caused sustained functional improvement in some children with PAH, although inhaled iloprost occasionally induced bronchoconstriction. Most patients tolerated the transition from intravenous to inhaled prostanoid therapy. Clinical deterioration, side effects, and poor compliance, owing to the frequency of treatments, could limit chronic treatment in children.
authors.affiliation: The Pulmonary Hypertension Program and Pediatric Heart Lung Center, Department of Pediatrics, The University of Colorado School of Medicine and The Children's Hospital, Denver, Colorado 80045, USA. ivy.dunbar@tchden.org
authors.forename: D Dunbar
authors.initials: DD
authors.lastname: Ivy
authors.forename: Aimee K
authors.initials: AK
authors.lastname: Doran
authors.forename: Kelly J
authors.initials: KJ
authors.lastname: Smith
authors.forename: George B
authors.initials: GB
authors.lastname: Mallory
authors.forename: Maurice
authors.initials: M
authors.lastname: Beghetti
authors.forename: Robyn J
authors.initials: RJ
authors.lastname: Barst
authors.forename: Daniela
authors.initials: D
authors.lastname: Brady
authors.forename: Yuk
authors.initials: Y
authors.lastname: Law
authors.forename: Donna
authors.initials: D
authors.lastname: Parker
authors.forename: Lori
authors.initials: L
authors.lastname: Claussen
authors.forename: Steven H
authors.initials: SH
authors.lastname: Abman
mesh_terms: D000280:Administration, Inhalation; D000293:Adolescent; D000367:Age Factors; D002648:Child; D002675:Child, Preschool; D015331:Cohort Studies; D004305:Dose-Response Relationship, Drug; D004334:Drug Administration Schedule; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D006976:Hypertension, Pulmonary / Q000175:diagnosis* / Q000188:drug therapy*; D016285:Iloprost / Q000008:administration & dosage*; D008297:Male; D015999:Multivariate Analysis; D011336:Probability; D012129:Respiratory Function Tests; D012189:Retrospective Studies; D018570:Risk Assessment; D012720:Severity of Illness Index; D013997:Time Factors; D016896:Treatment Outcome; D014655:Vascular Resistance / Q000187:drug effects; D014665:Vasodilator Agents / Q000008:administration & dosage*
chemical_list: D014665:Vasodilator Agents; D016285:Iloprost