title: Long-term pediatric outcome of isolated discrete subaortic stenosis.
abstract: BACKGROUND
  The management of pediatric discrete subaortic stenosis remains controversial.
  
  
  OBJECTIVE
  Document the natural history and surgical outcomes for discrete subaortic stenosis to adolescence.
  
  
  METHODS
  Retrospective review of clinical and echocardiographic findings in 74 patients diagnosed in childhood between 1985 and 1998.
  
  
  RESULTS
  Twenty-five patients were followed only medically for 9.4 ± 0.9 years to 15.9 ± 0.6 years of age. Their echocardiographic left ventricular outflow peak gradient did not progress, 19 ± 1.4 (SEM) vs 20 ± 2.3 mm Hg. The proportion with aortic insufficiency (AI) increased (4% to 52%). Forty-nine patients were operated for discrete subaortic stenosis at 7.8 ± 0.6 years. Their peak gradient at diagnosis was 36 ± 3 mm Hg with AI in 33%. Preoperatively their peak gradient progressed to 60 ± 5 mm Hg with AI in 82%. Assessment 6.2 ± 0.5 years postoperativly showed a peak gradient of 14 ± 2 mm Hg with AI in 88%. Ten patients required reoperation for recurrent discrete subaortic stenosis, 3 acquired complete heart block, and 1 developed endocarditis. There was no mortality. At diagnosis, surgical patients were younger, had greater peak gradients, and greater incidence of AI, than those followed only medically. The progression of discrete subaortic stenosis was positively associated with severity of obstruction and negatively associated with older age at diagnosis. The risk of having surgery over time was associated with greater preoperative obstruction and presence of AI.
  
  
  CONCLUSIONS
  Many pediatric patients with mild discrete subaortic stenosis exhibit little progression of obstruction and need not undergo immediate surgery. Others with more severe stenosis may progress precipitously and will benefit from early resection.
authors.affiliation: Montréal Children's Hospital, McGill University Health Centre, Montréal, Québec, Canada.
authors.forename: Christian
authors.initials: C
authors.lastname: Drolet
authors.forename: Joaquim
authors.initials: J
authors.lastname: Miro
authors.forename: Jean-Marc
authors.initials: JM
authors.lastname: Côté
authors.forename: John
authors.initials: J
authors.lastname: Finley
authors.forename: Letizia
authors.initials: L
authors.lastname: Gardin
authors.forename: Charles V
authors.initials: CV
authors.lastname: Rohlicek
mesh_terms: D000293:Adolescent; D000367:Age Factors; D002648:Child; D002675:Child, Preschool; D015331:Cohort Studies; D021922:Discrete Subaortic Stenosis / Q000151:congenital / Q000000981:diagnostic imaging / Q000628:therapy*; D018450:Disease Progression; D015150:Echocardiography, Doppler / Q000379:methods; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008991:Monitoring, Physiologic / Q000379:methods; D015999:Multivariate Analysis; D016016:Proportional Hazards Models; D011792:Quebec; D012044:Regression Analysis; D012189:Retrospective Studies; D018570:Risk Assessment; D012720:Severity of Illness Index; D012737:Sex Factors; D013997:Time Factors; D014656:Vascular Surgical Procedures / Q000379:methods*; D014665:Vasodilator Agents / Q000627:therapeutic use*
chemical_list: D014665:Vasodilator Agents