title: Midterm results of balloon dilation of congenital aortic stenosis: predictors of success.
abstract: OBJECTIVE
  We evaluated patient and procedural characteristics that influence the midterm success of balloon dilation of congenital aortic stenosis.
  
  
  BACKGROUND
  Balloon dilation is a new treatment for congenital aortic stenosis. Factors that influence midterm success are unknown.
  
  
  METHODS
  We performed a retrospective review of 148 children >1 month old who underwent balloon dilation for aortic stenosis.
  
  
  RESULTS
  Balloon dilation was successful in 87% of patients, with a procedural mortality rate of 0.7%. The average immediate peak to peak gradient reduction was 56.4 +/- 19.9% (mean +/- SD). Prior valvotomy was the only factor that significantly reduced the immediate gradient reduction after dilation (47.1 +/- 21.8% vs. 57.8 +/- 19.6%, p < 0.01). Survival after dilation was 95% at 8 years. Seventy-five percent of patients were free of repeat intervention 4 years after dilation, whereas 50% remained free of repeat intervention at 8 years. Asymmetrically thick valve leaflets (risk ratio [RR] 0.17, p < 0.01) and prior aortic valvotomy (RR 0.35, p = 0.02) decreased the risk of repeat intervention. Aortic regurgitation grade > or = 3 (RR 4.27, p = 0.04) and residual gradient after dilation (RR 1.63 for 10 mm Hg, p < 0.01) increased the risk.
  
  
  CONCLUSIONS
  The 8-year survival rate after dilation was 95% with 50% of patients free of repeat intervention. Factors that increased the risk for repeat intervention included symmetrically thin or thick aortic valve leaflets, regurgitation grade > or = 3 after dilation and a high residual gradient after dilation. The incidence of repeat intervention after dilation was high owing to its palliative nature.
authors.affiliation: Children's Hospital, Boston and Harvard Medical School, Cambridge, Massachusetts, USA.
authors.forename: P
authors.initials: P
authors.lastname: Moore
authors.forename: E
authors.initials: E
authors.lastname: Egito
authors.forename: H
authors.initials: H
authors.lastname: Mowrey
authors.forename: S B
authors.initials: SB
authors.lastname: Perry
authors.forename: J E
authors.initials: JE
authors.lastname: Lock
authors.forename: J F
authors.initials: JF
authors.lastname: Keane
mesh_terms: D000293:Adolescent; D000328:Adult; D001024:Aortic Valve Stenosis / Q000151:congenital / Q000401:mortality / Q000628:therapy*; D002404:Catheterization; D002648:Child; D002675:Child, Preschool; D006801:Humans; D007223:Infant; D016019:Survival Analysis