title: The prognostic utility of cardiopulmonary exercise testing stands the test of time in patients with heart failure.
abstract: BACKGROUND
  While the medical management strategy for patients with heart failure (HF) has dramatically changed, cardiopulmonary exercise testing (CPX) procedures and the data obtained have remained relatively stable. We are unaware of any previous investigation that has assessed differences in the prognostic utility of CPX in HF according to time period, reflecting differences in the clinical management of systolic HF.
  
  
  METHODS
  Subjects (n = 381) underwent CPX between April 1, 1993, and December 31, 2005, and the remaining 511 were tested between January 1, 2006, and October 28, 2010. Peak oxygen uptake ((Equation is included in full-text article.)O2) and the minute ventilation/carbon dioxide production ((Equation is included in full-text article.)E/(Equation is included in full-text article.)CO2) slope were ascertained for all tests.
  
  
  RESULTS
  Both the (Equation is included in full-text article.)E/(Equation is included in full-text article.)CO2 slope and peak (Equation is included in full-text article.)O2 were strong univariate predictors of adverse events in both subgroups. In the multivariate analysis, the (Equation is included in full-text article.)E/(Equation is included in full-text article.)CO2 slope was the strongest predictive marker while peak (Equation is included in full-text article.)O2 added predictive value and was retained in the regression for all scenarios. In subjects undergoing CPX before 2006, a (Equation is included in full-text article.)E/(Equation is included in full-text article.)CO2 slope 45 or greater and a peak (Equation is included in full-text article.)O2 of less than 10 mL · kg · min generated a hazard ratio of 4.2 (95% CI: 1.9-9.1, P < .001) when considering only mortality as an endpoint. In subjects undergoing CPX after 2006, a (Equation is included in full-text article.)E/(Equation is included in full-text article.)CO2 slope 45 or greater and a peak (Equation is included in full-text article.)O2 of less than 10 mL · kg · min generated a hazard ratio of 8.2 (95% CI: 4.7-14.3, P < .001) when considering only mortality as an endpoint.
  
  
  CONCLUSIONS
  The results of this study indicate that CPX continues to be a valuable clinical assessment in the present-day HF management.
authors: Department of Orthopaedics, University of New Mexico Health Sciences Center, HSSB Room 204F, MSC09 5230, Albuquerque, NM 87131, USA. RArena@salud.unm.edu
authors: Ross
authors: R
authors: Arena
authors: Marco
authors: M
authors: Guazzi
authors: Jonathan
authors: J
authors: Myers
authors: Paul
authors: P
authors: Chase
authors: Daniel
authors: D
authors: Bensimhon
authors: Lawrence P
authors: LP
authors: Cahalin
authors: Mary Ann
authors: MA
authors: Peberdy
authors: Euan
authors: E
authors: Ashley
authors: Erin
authors: E
authors: West
authors: Daniel E
authors: DE
authors: Forman
mesh_terms: D016009:Chi-Square Distribution; D016001:Confidence Intervals; D005080:Exercise Test / Q000295:instrumentation*; D017079:Exercise Tolerance; D005260:Female; D006333:Heart Failure / Q000188:drug therapy / Q000473:pathology / Q000523:psychology / Q000534:rehabilitation*; D006801:Humans; D016014:Linear Models; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D010101:Oxygen Consumption / Q000502:physiology; D011379:Prognosis; D013995:Time