title: Exercise responses of elderly patients with diastolic versus systolic heart failure.
abstract: OBJECTIVE
  Little information is available regarding peak and submaximal exercise performance in elderly heart failure (HF) patients, particularly in those with diastolic dysfunction (DD). Therefore, the purpose of this investigation was to compare exercise responses of elderly patients with HF due to either systolic dysfunction (SD) or DD, to age-matched healthy volunteers (HV).
  
  
  METHODS
  Patients with chronic HF > or = 60 yr (N = 119) due to SD (N = 60) or primary DD (N = 59) underwent a maximal cycle ergometry test with expired gas analysis and venous lactate measurement. Twenty-eight HV > or = 60 yr served as a control group. Anaerobic threshold was determined by gas analysis (ATVEN) and by plasma lactate rise (ATLAC).
  
  
  RESULTS
  Peak oxygen consumption (VO(2peak)) was significantly (P < 0.001) reduced in both SD and DD patients (13 +/- 0.4 vs 14 +/- 0.4 ml x kg(-1) x min(-1), respectively) versus HV (20 +/- 0.6 ml x kg(-1) x min(-1)). Peak heart rate was reduced in patients versus HV (131 +/- 3 bpm vs 145 +/- 4, respectively; P < or = 0.01), but heart rate at a given submaximal work rate was significantly lower (P < or = 0.01) in HV than in SD and DD patients. ATVEN of 11.8 +/- 0.3 ml x kg(-1) x min(-1) for HV was significantly higher than SD (8.9 +/- 0.2) and DD (9.2 +/- 0.3). Peak lactate concentration was 6.6 +/- 0.6 mmol x kg(-1) x l(-1) in HV and was significantly reduced in both SD and DD HF patients. ATVEN correlated well with ATLAC in HV and in DD patients, but not in SD patients.
  
  
  CONCLUSIONS
  Submaximal and peak exercise performance are markedly altered in elderly HF patients compared with age-matched HV but do not appear to be different between SD and DD patients.
authors.affiliation: Department of Health and Exercise Science, Wake Forest University, Winston-Salem, NC 27109, USA. brubaker@wfu.edu
authors.forename: Peter H
authors.initials: PH
authors.lastname: Brubaker
authors.forename: Christian T
authors.initials: CT
authors.lastname: Marburger
authors.forename: Timothy M
authors.initials: TM
authors.lastname: Morgan
authors.forename: Brittany
authors.initials: B
authors.lastname: Fray
authors.forename: Dalane W
authors.initials: DW
authors.lastname: Kitzman
mesh_terms: D000368:Aged; D000375:Aging / Q000502:physiology*; D015308:Anaerobic Threshold; D003971:Diastole; D015444:Exercise / Q000502:physiology*; D017079:Exercise Tolerance; D005260:Female; D006333:Heart Failure / Q000503:physiopathology*; D006801:Humans; D019344:Lactic Acid / Q000097:blood; D008297:Male; D008875:Middle Aged; D013599:Systole
chemical_list: D019344:Lactic Acid