Table 1

Clinical characteristics

Healthy controls (n=7)CTEPH (n=14)p Value
Age, years51±261±40.065
Male sex, %71711.000
Weight, kg78±784±50.535
BMI, kg/m225.8±2.128.2±1.50.360
BSA, m21.92±0.081.96±0.070.745
NYHA functional class, n
NTproBNP, ng/L39 (37–56)537 (239–1428)0.001
Hb, g/dL13.4±0.315.0±0.30.005
Creatinine, mg/dL0.78±0.030.85±0.050.265
6MWD, m359±42
CPET parameters
Peak power output, W221±2778±80.001
Peak heart rate, bpm170±7126±6<0.001
VO2peak, mL/kg/min34.4±4.313.2±1.10.002
Vd/Vt, %26±145±2<0.001
PA-aO2, mm Hg29±662±4<0.001
P(c-ET)CO2, mm Hg0.33±1.27.4±0.8<0.001
VE/VO2 at AT24.2±0.542.2±1.9<0.001
VE/VCO2 at AT24.9±0.548.3±2.2<0.001
PETCO2 at AT, mm Hg42.8±1.223.3±1.1<0.001
  • Data presented as mean±SE or median (25% and 75% percentile); p values from Fisher's exact test, unpaired two-sample t tests or Mann–Whitney test were appropriate.

  • AT, anaerobic threshold; BMI, Body Mass Index; BSA, body surface area; CPET, cardiopulmonary exercise testing; CTEPH, chronic thromboembolic pulmonary hypertension; Hb, haemoglobin; 6MWD, 6 min walking distance; NTproBNP, N-terminal pro-brain natriuretic peptide; NYHA, New York Heart Association; P(c-ET)CO2, capillary to end-tidal carbon dioxide gradient; PA-aO2, alveolar-arterial oxygen tension difference; PETCO2, end-tidal carbon dioxide tension; Vd/VT, ratio of dead-space to tidal volume; VE/VCO2, ventilatory equivalent of carbon dioxide; VE/VO2, ventilatory equivalent of oxygen; VO2peak, peak oxygen consumption.