title: Prognostic value of cardiopulmonary exercise testing using percent achieved of predicted peak oxygen uptake for patients with ischemic and dilated cardiomyopathy.
abstract: OBJECTIVE
  We tested the hypothesis that percent achieved of predicted peak oxygen uptake (predicted VO2max) improves the prognostic accuracy of identifying high risk ambulatory patients with congestive heart failure considered for heart transplantation compared with absolute peak oxygen uptake (VO2max) in 181 patients with ischemic or dilated cardiomyopathy.
  
  
  BACKGROUND
  Peak oxygen uptake during exercise has been shown to be a useful prognostic measurement to risk stratify patients with heart failure. The prognostic value of percent predicted VO2max has not been assessed in these patients.
  
  
  METHODS
  We retrospectively studied 181 ambulatory patients referred to the Saint Louis University Heart Failure Unit. Clinical, hemodynamic (137 patients) and coronary angiographic (145 patients) data were recorded, and all patients underwent symptom-limited cardiopulmonary exercise.
  
  
  RESULTS
  During a mean follow-up period of 12 +/- 6 months, 26 patients died, and 18 were listed as Status 1 priority for heart transplantation. The actuarial 1- and 2-year survival of the 89 patients who achieved < or = 50% predicted VO2max was 74% and 43%, respectively, compared with 98% and 90% in the 92 who achieved > 50% predicted VO2max (p = 0.001). Multivariable analysis selected < or = 50% predicted VO2max as the most significant predictor of cardiac death (p = 0.007) and cardiac death or Status 1 priority (p = 0.0005).
  
  
  CONCLUSIONS
  Percent achieved of predicted VO2max provides important information that can be used to risk stratify ambulatory patients with heart failure with ischemic or dilated etiology that exceeds that provided by measurement of VO2max alone. Patients who achieve > 50% predicted VO2max have an excellent short-term prognosis when treated medically, and heart transplantation can be safely deferred.
authors.affiliation: Department of Internal Medicine, Saint Louis University School of Medicine, Missouri 63110-0250, USA.
authors.forename: A M
authors.initials: AM
authors.lastname: Stelken
authors.forename: L T
authors.initials: LT
authors.lastname: Younis
authors.forename: S H
authors.initials: SH
authors.lastname: Jennison
authors.forename: D D
authors.initials: DD
authors.lastname: Miller
authors.forename: L W
authors.initials: LW
authors.lastname: Miller
authors.forename: L J
authors.initials: LJ
authors.lastname: Shaw
authors.forename: D
authors.initials: D
authors.lastname: Kargl
authors.forename: B R
authors.initials: BR
authors.lastname: Chaitman
mesh_terms: D002311:Cardiomyopathy, Dilated / Q000175:diagnosis* / Q000401:mortality / Q000628:therapy; D016022:Case-Control Studies; D005080:Exercise Test; D017079:Exercise Tolerance / Q000502:physiology*; D005260:Female; D005500:Follow-Up Studies; D006333:Heart Failure / Q000175:diagnosis* / Q000401:mortality / Q000628:therapy; D016027:Heart Transplantation; D006801:Humans; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D010101:Oxygen Consumption; D011237:Predictive Value of Tests; D011379:Prognosis; D012189:Retrospective Studies; D012307:Risk Factors; D016019:Survival Analysis; D015996:Survival Rate; D013997:Time Factors