title: Cardiopulmonary Exercise Testing in Patients with Asymptomatic or Equivocal Symptomatic Aortic Stenosis: Feasibility, Reproducibility, Safety and Information Obtained on Exercise Physiology.
abstract: OBJECTIVE
  The aim of this study was to determine the feasibility, reproducibility, safety and information obtained on exercise physiology from cardiopulmonary exercise testing (CPX) in patients with aortic stenosis.
  
  
  METHODS
  Patients with an aortic valve area (AVA) <1.3 cm2 who were judged asymptomatic or equivocal symptomatic underwent CPX and an inert gas rebreathing test. Only those where comprehensive evaluation of CPX results indicated haemodynamic compromise from aortic stenosis were referred for valve replacement.
  
  
  RESULTS
  The mean patient age was 72 (±9) years; an AVA index <0.6 cm2/m2 and equivocal symptomatic status were found in 90 and 70%, respectively. CPX was feasible in 130 of the 131 patients. The coefficients of repeatability by test-retest were 5.4% (pVO2) and 4.6% (peak O2 pulse). A pVO2 <83% of the expected was predicted by a lower stroke volume at exercise, lower peak heart rate and FEV1, and higher VE/VCO2, but not by AVA index. Equivocal symptomatic status and a low gradient but high valvulo-arterial impedance were associated with a lower pVO2, but not with an inability to increase stroke volume. In total, 18 patients were referred for valve replacement. At 1 year, no cardiovascular deaths had occurred.
  
  
  CONCLUSIONS
  CPX was feasible and reproducible and provided comprehensive data on exercise physiology. A CPX-guided treatment strategy was safe up to 1 year.
authors.affiliation: Department of Cardiology, Roskilde University Hospital, Roskilde, Denmark.
authors.forename: Douet
authors.initials: D
authors.lastname: van Le
authors.forename: Gunnar Vagn Hagemann
authors.initials: GV
authors.lastname: Jensen
authors.forename: Steen
authors.initials: S
authors.lastname: Carstensen
authors.forename: Lars
authors.initials: L
authors.lastname: Kjøller-Hansen
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D001024:Aortic Valve Stenosis / Q000150:complications / Q000401:mortality / Q000503:physiopathology* / Q000601:surgery; D003718:Denmark / Q000453:epidemiology; D004452:Echocardiography; D015444:Exercise / Q000502:physiology*; D005080:Exercise Test / Q000379:methods; D017079:Exercise Tolerance / Q000502:physiology*; D005260:Female; D005541:Forced Expiratory Volume; D006350:Heart Valve Prosthesis; D006439:Hemodynamics; D006785:Hospitals, University; D006801:Humans; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D029424:Pulmonary Disease, Chronic Obstructive / Q000150:complications