title: Risk factors for reoperation after repair of discrete subaortic stenosis in children.
abstract: OBJECTIVE
  This study aimed to identify independent predictors of reoperation after successful resection of discrete subaortic stenosis (DSS).
  
  
  BACKGROUND
  Recurrence of DSS has been reported to range from 0% to 55% of patients. Factors associated with recurrence have not been adequately defined.
  
  
  METHODS
  Patients were included if they had a diagnosis of DSS, normal segmental cardiac anatomy, previous resection of DSS, and at least 36 months' follow-up. Demographic, surgical, and echocardiographic data were analyzed. Primary outcome was repeat resection of DSS in patients after successful primary resection.
  
  
  RESULTS
  Of 111 subjects who had successful surgical resection of DSS, 16 patients (14%) required reoperation. Median follow-up time was 8.2 years. Form of DSS and gender did not differ significantly between those with reoperation and those without. In multivariate analysis, independent predictors of reoperation that would be available before first surgery were <6 mm distance between the aortic valve (AoV) and the obstruction (hazard ratio [HR] 5.1; p = 0.013) and peak gradient by Doppler > or =60 mm Hg (HR 4.2; p = 0.016). If intraoperative variables are also considered, peeling of the membrane from the AoV or mitral valve at first surgery, <6 mm distance between the DSS and AoV, and peak gradient by Doppler > or =60 mm Hg were independent predictors of reoperation.
  
  
  CONCLUSIONS
  Proximity of the obstructive lesion to the AoV and severe obstruction determined by preoperative echocardiography, as well as involvement of valve leaflets requiring surgical peeling, predict recurrent DSS requiring reoperation.
authors.affiliation: Department of Cardiology, Children's Hospital Boston, and Harvard Medical School, Boston, Massachusetts 02115, USA.
authors.forename: Alon
authors.initials: A
authors.lastname: Geva
authors.forename: Colin J
authors.initials: CJ
authors.lastname: McMahon
authors.forename: Kimberlee
authors.initials: K
authors.lastname: Gauvreau
authors.forename: Laila
authors.initials: L
authors.lastname: Mohammed
authors.forename: Pedro J
authors.initials: PJ
authors.lastname: del Nido
authors.forename: Tal
authors.initials: T
authors.lastname: Geva
mesh_terms: D000293:Adolescent; D000328:Adult; D006348:Cardiac Surgical Procedures; D002648:Child; D002675:Child, Preschool; D021922:Discrete Subaortic Stenosis / Q000000981:diagnostic imaging / Q000601:surgery*; D018450:Disease Progression; D005260:Female; D006801:Humans; D007223:Infant; D008297:Male; D011379:Prognosis; D012008:Recurrence; D012086:Reoperation; D012189:Retrospective Studies; D012307:Risk Factors; D014463:Ultrasonography