title: The initial slope of the VCO2/VO2-curve (s1) in cardiopulmonary exercise testing is a strong and independent predictor of outcome in patients with previous myocardial infarction.
abstract: BACKGROUND
  Detecting heart failure (HF) patients at risk is a relevant clinical problem. Our goal was to define associations of clinical HF-markers and exercise parameters with respect to their prognostic power in HF-patients.
  
  
  METHODS
  We performed cardiopulmonary exercise testing (CPET) in 103 ischemic HF-patients. CPET-parameters included peak VO(2), VO(2) at AT, peak oxygen pulse, minimal CO(2) and O(2) equivalents, VE/VCO(2) and s1, a motivation-independent and submaximal parameter representing the initial slope of the VCO(2)/VO(2)-curve that has not been described in HF-patients so far.
  
  
  RESULTS
  Median follow-up was 668 days. The combined endpoint of cardiovascular death and rehospitalization due to HF occurred in 14 patients. Patients with/without events differed significantly regarding their age, NYHA-class, LVEF and NT-proBNP serum-levels. Patients with events had significantly lower peak VO(2)- and higher s1-values. NT-proBNP serum-levels, NYHA-class and LVEF were significantly correlated with peak VO(2). Only age, peak VO(2) and s1 were independent predictors of adverse events. Using multivariate analysis, s1 was a strong and independent parameter with good sensitivity and specificity.
  
  
  CONCLUSIONS
  s1 is an independent and powerful predictor in HF-patients. Since s1 is independent of maximal exercise capacity, s1 might be more accurate for the evaluation of HF-patients not willing or unable to perform maximal exercise.
authors.affiliation: Dept. of Cardiology, J. W. Goethe University Hospital, Theodor-Stern-Kai 7, 60590, Frankfurt/Main, Germany.
authors.forename: Joerg
authors.initials: J
authors.lastname: Honold
authors.forename: Lenka
authors.initials: L
authors.lastname: Geiger
authors.forename: Birgit
authors.initials: B
authors.lastname: Assmus
authors.forename: Ulrich
authors.initials: U
authors.lastname: Fischer-Rasokat
authors.forename: Volker
authors.initials: V
authors.lastname: Schaechinger
authors.forename: Andreas M
authors.initials: AM
authors.lastname: Zeiher
authors.forename: Ioakim
authors.initials: I
authors.lastname: Spyridopoulos
mesh_terms: D000328:Adult; D000367:Age Factors; D000368:Aged; D002245:Carbon Dioxide / Q000378:metabolism; D005080:Exercise Test / Q000379:methods*; D005260:Female; D005500:Follow-Up Studies; D006333:Heart Failure / Q000175:diagnosis* / Q000401:mortality / Q000503:physiopathology; D006801:Humans; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D009203:Myocardial Infarction / Q000503:physiopathology*; D010101:Oxygen Consumption; D010359:Patient Readmission / Q000706:statistics & numerical data; D011237:Predictive Value of Tests; D011379:Prognosis; D018570:Risk Assessment / Q000379:methods; D012680:Sensitivity and Specificity; D016896:Treatment Outcome
chemical_list: D002245:Carbon Dioxide