title: Discrete subaortic stenosis: incidence, morphology and surgical impact of associated subaortic anomalies.
abstract: BACKGROUND
  The association between discrete subaortic stenosis and other subaortic anomalies is a well known but rarely reported occurrence. The aim of this study is to define the incidence, morphology, and surgical impact of associated anomalies of the left ventricular outflow tract in children operated on for discrete subaortic stenosis.
  
  
  METHODS
  Between 1994 and 2000, 45 consecutive children were operated on for discrete subaortic stenosis. Patients were divided in two groups according to the obstructive lesion detected by echocardiography.
  
  
  RESULTS
  A localized shelf was found as an isolated lesion in 31 patients (group A), whereas additional subaortic anomalies were found in 14 cases (31%) and were multiple in 5 cases (group B). The anomalies included anomalous septal insertion of mitral valve (7 cases); accessory mitral valve tissue (2 cases); anomalous papillary muscle (2 cases); anomalous muscular band (8 cases); and muscularization of the anterior mitral valve leaflet (1 case). Cardiopulmonary bypass and aortic cross-clamping times were significantly shorter in group A. There were no operative deaths nor major complications or deaths during follow-up. A gradient of 15 mm Hg or more was found at follow-up in 5 cases whereas aortic regurgitation was estimated to be not clinically significant in all but 1 patient. Six cases of recurrent subaortic stenosis were found in our series, 3 of them with other subaortic anomalies.
  
  
  CONCLUSIONS
  This study shows that discrete subaortic stenosis can often be associated with other subaortic abnormalities. Surgical treatment of these anomalies produces excellent early and mid-term relief of obstruction without any increase in mortality and morbidity.
authors.affiliation: Laboratory of Interventional Cardiology, Division of Cardiovascular Surgery, Giannina Gaslini Institute, Children's Hospital, Genova, Italy. mauriziomarasini@istituto-gaslini.ge.it
authors.forename: Maurizio
authors.initials: M
authors.lastname: Marasini
authors.forename: Lucio
authors.initials: L
authors.lastname: Zannini
authors.forename: Gian Paolo
authors.initials: GP
authors.lastname: Ussia
authors.forename: Robin
authors.initials: R
authors.lastname: Pinto
authors.forename: Rodolfo
authors.initials: R
authors.lastname: Moretti
authors.forename: Franco
authors.initials: F
authors.lastname: Lerzo
authors.forename: Giacomo
authors.initials: G
authors.lastname: Pongiglione
mesh_terms: D000293:Adolescent; D001020:Aortic Stenosis, Subvalvular / Q000000981:diagnostic imaging / Q000453:epidemiology / Q000601:surgery*; D002648:Child; D002675:Child, Preschool; D004452:Echocardiography; D005260:Female; D005500:Follow-Up Studies; D006330:Heart Defects, Congenital / Q000000981:diagnostic imaging / Q000453:epidemiology / Q000601:surgery*; D006439:Hemodynamics / Q000502:physiology; D006801:Humans; D015994:Incidence; D008297:Male; D008943:Mitral Valve / Q000002:abnormalities / Q000000981:diagnostic imaging / Q000601:surgery; D010210:Papillary Muscles / Q000002:abnormalities / Q000000981:diagnostic imaging / Q000601:surgery; D011183:Postoperative Complications / Q000000981:diagnostic imaging / Q000453:epidemiology / Q000209:etiology; D012307:Risk Factors; D014694:Ventricular Outflow Obstruction / Q000000981:diagnostic imaging / Q000453:epidemiology / Q000601:surgery*