title: Modest increase in peak VO2 is related to better clinical outcomes in chronic heart failure patients: results from heart failure and a controlled trial to investigate outcomes of exercise training.
abstract: BACKGROUND
  The prognostic ability of a single measurement of peak oxygen uptake (VO(2)) is well established in patients with chronic heart failure. The relation between a change in peak VO(2) and clinical outcomes is not well defined.
  
  
  RESULTS
  This investigation determined whether an increase in peak VO(2) was associated with a lower risk of the primary end point of time to all-cause mortality or all-cause hospitalization and 3 secondary end points. In Heart Failure and a Controlled Trial to Investigate Outcomes of Exercise Training, an exercise training trial for patients with systolic heart failure, cardiopulmonary exercise tests were performed at baseline and ≈3 months later in 1620 participants. Median peak VO(2) in the combined sample increased from 15.0 (11.9-18.0 Q1-Q3) to 15.4 (12.3-18.7 Q1-Q3) mL·kg(-1)·min(-1). Every 6% increase in peak VO(2,) adjusted for other significant predictors, was associated with a 5% lower risk of the primary end point (hazard ratio=0.95; CI=0.93-0.98; P<0.001); a 4% lower risk of the secondary end point of time to cardiovascular mortality or cardiovascular hospitalization (hazard ratio=0.96; CI=0.94-0.99; P<0.001); an 8% lower risk of cardiovascular mortality or heart failure hospitalization (hazard ratio=0.92; CI=0.88-0.96; P<0.001); and a 7% lower all-cause mortality (hazard ratio=0.93; CI=0.90-0.97; P<0.001).
  
  
  CONCLUSIONS
  Among patients with chronic systolic heart failure, a modest increase in peak VO(2) over 3 months was associated with a more favorable outcome. Monitoring the change in peak VO(2) for such patients may have benefit in assessing prognosis.
authors: Exercise Physiology Laboratory University of Louisville, Louisville, KY 40292, USA. swank@louisville.edu
authors: Ann M
authors: AM
authors: Swank
authors: John
authors: J
authors: Horton
authors: Jerome L
authors: JL
authors: Fleg
authors: Gregg C
authors: GC
authors: Fonarow
authors: Steven
authors: S
authors: Keteyian
authors: Lee
authors: L
authors: Goldberg
authors: Gene
authors: G
authors: Wolfel
authors: Eileen M
authors: EM
authors: Handberg
authors: Dan
authors: D
authors: Bensimhon
authors: Marie-Christine
authors: MC
authors: Illiou
authors: Marianne
authors: M
authors: Vest
authors: Greg
authors: G
authors: Ewald
authors: Gordon
authors: G
authors: Blackburn
authors: Eric
authors: E
authors: Leifer
authors: Lawton
authors: L
authors: Cooper
authors: William E
authors: WE
authors: Kraus
mesh_terms: D000368:Aged; D002908:Chronic Disease; D005080:Exercise Test; D005081:Exercise Therapy; D017079:Exercise Tolerance; D005260:Female; D054143:Heart Failure, Systolic / Q000175:diagnosis / Q000401:mortality / Q000503:physiopathology / Q000628:therapy*; D006760:Hospitalization; D006801:Humans; D008297:Male; D008875:Middle Aged; D010101:Oxygen Consumption; D011237:Predictive Value of Tests; D016016:Proportional Hazards Models; D020127:Recovery of Function; D018570:Risk Assessment; D012307:Risk Factors; D016019:Survival Analysis; D013997:Time Factors; D016896:Treatment Outcome; D014481:United States