title: Cardiopulmonary exercise testing reflects similar pathophysiology and disease severity in heart failure patients with reduced and preserved ejection fraction.
abstract: BACKGROUND
  We are unaware of any previous investigation that has compared the relationship of key cardiopulmonary exercise testing (CPX) variables to various measures of pathophysiology between heart failure-reduced ejection fraction (HFrEF) and HF-preserved ejection fraction (HFpEF) cohorts that are well matched with respect to baseline characteristics and their exercise response, which is the purpose of the present study.
  
  
  METHODS
  Thirty-four patients with HFpEF were randomly matched to 34 subjects with HFrEF according to age and sex as well as peak oxygen consumption (VO2), ventilatory efficiency (VE/VCO2 slope), and exercise oscillatory ventilation (EOV). In addition to CPX, patients also underwent echocardiography with tissue Doppler imaging (TDI) and assessment of N-terminal pro-B-type natriuretic peptide (NT-proBNP).
  
  
  RESULTS
  When matched for age, sex, and CPX variables, the HFrEF and HFpEF cohorts had similar echocardiography with TDI and NT-proBNP values, indicating comparable disease severity. In addition, the correlations between key CPX measures (peak VO2 and VE/VCO2 slope) and echocardiography with TDI and NT-proBNP measures were similar between HFrEF and HFpEF groups. Of note, the correlation between the VE/VCO2 slope and pulmonary artery systolic pressure and NT-proBNP was highly significant in both groups (r ≥ 0.65, p < 0.01). Moreover, subjects with EOV in both groups had a significantly higher PASP (∼47 vs. ∼35 mmHg, p < 0.05).
  
  
  CONCLUSIONS
  The results of the current study indicate CPX equally represents disease severity in HFrEF and HFpEF patients. This is a novel finding supporting the key role of CPX in the clinical follow-up of HF patients irrespective of LVEF and cardiac phenotype.
authors: University of Milan, San Donato Milanese, Italy marco.guazzi@unimi.it.
authors: Marco
authors: M
authors: Guazzi
authors: University of Milan, San Donato Milanese, Italy.
authors: Valentina
authors: V
authors: Labate
authors: University of Miami, Miami, USA.
authors: Lawrence P
authors: LP
authors: Cahalin
authors: University of New Mexico, Albuquerque, New Mexico.
authors: Ross
authors: R
authors: Arena
mesh_terms: D000368:Aged; D015150:Echocardiography, Doppler; D005080:Exercise Test / Q000379:methods*; D017079:Exercise Tolerance / Q000502:physiology*; D005260:Female; D006333:Heart Failure / Q000503:physiopathology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D020097:Natriuretic Peptide, Brain / Q000097:blood; D010101:Oxygen Consumption; D010446:Peptide Fragments / Q000097:blood; D013318:Stroke Volume / Q000502:physiology*
chemical_list: D010446:Peptide Fragments; C109794:pro-brain natriuretic peptide (1-76); D020097:Natriuretic Peptide, Brain
keywords: Diastolic; systolic; ventilatory expired gas; ventricle