title: Hemodynamic determinants of the abnormal cardiopulmonary exercise response in heart failure with preserved left ventricular ejection fraction.
abstract: BACKGROUND
  The cardiopulmonary exercise testing (CPET) response in heart failure with preserved left ventricular ejection fraction (HFPEF) is incompletely understood. We aimed to describe the CPET response in HFPEF and to assess its invasive hemodynamic determinants.
  
  
  RESULTS
  Ten patients with HFPEF and 8 asymptomatic controls underwent resting and exercise right heart catheterization and maximal symptom-limited CPET. The slope of the minute ventilation/carbon dioxide production relationship (VE/VCO(2) slope; 34.3 ± 5.4 vs. 28.4 ± 3.4; P = .02) was steeper, peak oxygen consumption (peak VO(2); 15.1 ± 4.9 vs. 26.6 ± 12.5 mL∗kg(-1)∗min(-1); P = .02) was lower, and heart rate recovery 1 minute after exercise termination (HRR-1; 10 ± 5 vs. 27 ± 10 beats/min; P < .001) was slower in HFPEF compared to controls. A steeper VE/VCO(2) slope (r = 0.67, P = .002), lower peak VO(2) (r = -0.48, P = .04), and slower HRR-1 (r = -0.58, P = .02) were significantly related to a higher ratio of the change in pulmonary capillary wedge pressure per change in work rate as a measure of the left ventricular pressure volume relationship.
  
  
  CONCLUSIONS
  In HFPEF patients, fundamental alterations in the CPET profile occur and these may, in part, result from the rapid rise in left ventricular filling pressures which accompanies exercise in these patients.
authors.affiliation: Heart Failure Research Group, Baker IDI Heart and Diabetes Institute, Melbourne, Australia.
authors.forename: Micha T
authors.initials: MT
authors.lastname: Maeder
authors.forename: Bruce R
authors.initials: BR
authors.lastname: Thompson
authors.forename: Nay
authors.initials: N
authors.lastname: Htun
authors.forename: David M
authors.initials: DM
authors.lastname: Kaye
mesh_terms: D000368:Aged; D002302:Cardiac Output; D005080:Exercise Test; D005081:Exercise Therapy; D017079:Exercise Tolerance / Q000502:physiology*; D005260:Female; D006305:Health Status Indicators; D006333:Heart Failure / Q000473:pathology / Q000628:therapy*; D006439:Hemodynamics; D006801:Humans; D008297:Male; D010101:Oxygen Consumption; D012123:Pulmonary Ventilation; D012129:Respiratory Function Tests; D013223:Statistics as Topic; D013318:Stroke Volume; D016277:Ventricular Function, Left