title: Exercise performance in children and adolescents after the Ross procedure.
abstract: OBJECTIVE
  The Ross procedure is increasingly utilized in the treatment of aortic valvar disease in children and adolescents. Our purpose was to compare pre- and post-operative exercise state in this population.
  
  
  METHODS
  We included patients who underwent the Ross procedure at our institution between January, 1995, and December, 2003, and in whom we had performed pre- and post-operative exercise stress tests. We used a ramp bicycle protocol to measure consumption of oxygen and production of carbon dioxide. Cardiac output was estimated from effective pulmonary blood flow by the helium acetylene re-breathing technique.
  
  
  RESULTS
  We studied 26 patients, having a median age at surgery of 15.7 years, with a range from 7.5 to 24.1 years. The primary indication for surgery in two-thirds was combined aortic stenosis and insufficiency. Median time from the operation to the post-operative exercise stress test was 17.4 months, with a range from 6.7 to 30.2 months. There was a trend toward lower maximal consumption of oxygen after the procedure, at 36.3 plus or minus 7.6 millilitres per kilogram per minute (83.9% predicted) as opposed to 38.6 plus or minus 8.4 millilitres per kilogram per minute (88.5% predicted, p equal to 0.06). Patients after the procedure, however, had significantly increased adiposity, so that there was no difference in maximal consumption of oxygen indexed to ideal body weight before and after the operation. In 20 of the patients, aerobic capacity improved or was stable after the operation. There was no post-operative chronotropic impairment.
  
  
  CONCLUSIONS
  In the majority of patients following the Ross procedure, exercise performance is stable and within the normal range of a healthy age and sex matched population, despite sedentary lifestyles and increased adiposity.
authors.affiliation: Division of Cardiology, at the Cardiac Center of The Children's Hospital of Philadelphia, and the Department of Pediatrics at the University of Pennsylvania School of Medicine 19104, USA.
authors.forename: Bradley S
authors.initials: BS
authors.lastname: Marino
authors.forename: Sara K
authors.initials: SK
authors.lastname: Pasquali
authors.forename: Gil
authors.initials: G
authors.lastname: Wernovsky
authors.forename: John R
authors.initials: JR
authors.lastname: Bockoven
authors.forename: Michael
authors.initials: M
authors.lastname: McBride
authors.forename: Catherine J
authors.initials: CJ
authors.lastname: Cho
authors.forename: Thomas L
authors.initials: TL
authors.lastname: Spray
authors.forename: Stephen M
authors.initials: SM
authors.lastname: Paridon
mesh_terms: D000293:Adolescent; D000328:Adult; D001022:Aortic Valve Insufficiency / Q000000981:diagnostic imaging / Q000503:physiopathology* / Q000601:surgery; D001024:Aortic Valve Stenosis / Q000000981:diagnostic imaging / Q000503:physiopathology* / Q000601:surgery; D002648:Child; D004452:Echocardiography; D015444:Exercise / Q000502:physiology*; D005080:Exercise Test; D005260:Female; D005500:Follow-Up Studies; D019918:Heart Valve Prosthesis Implantation / Q000379:methods*; D006801:Humans; D008297:Male; D010101:Oxygen Consumption / Q000502:physiology; D011184:Postoperative Period; D012189:Retrospective Studies; D013318:Stroke Volume / Q000502:physiology