Clinical characteristics
| Healthy controls (n=7) | CTEPH (n=14) | p Value | |
|---|---|---|---|
| Age, years | 51±2 | 61±4 | 0.065 |
| Male sex, % | 71 | 71 | 1.000 |
| Weight, kg | 78±7 | 84±5 | 0.535 |
| BMI, kg/m2 | 25.8±2.1 | 28.2±1.5 | 0.360 |
| BSA, m2 | 1.92±0.08 | 1.96±0.07 | 0.745 |
| NYHA functional class, n | |||
| I | − | 1 | − |
| II | − | 4 | − |
| III | − | 9 | − |
| IV | − | 0 | − |
| NTproBNP, ng/L | 39 (37–56) | 537 (239–1428) | 0.001 |
| Hb, g/dL | 13.4±0.3 | 15.0±0.3 | 0.005 |
| Creatinine, mg/dL | 0.78±0.03 | 0.85±0.05 | 0.265 |
| 6MWD, m | − | 359±42 | − |
| CPET parameters | |||
| Peak power output, W | 221±27 | 78±8 | 0.001 |
| Peak heart rate, bpm | 170±7 | 126±6 | <0.001 |
| VO2peak, mL/kg/min | 34.4±4.3 | 13.2±1.1 | 0.002 |
| Vd/Vt, % | 26±1 | 45±2 | <0.001 |
| PA-aO2, mm Hg | 29±6 | 62±4 | <0.001 |
| P(c-ET)CO2, mm Hg | 0.33±1.2 | 7.4±0.8 | <0.001 |
| VE/VO2 at AT | 24.2±0.5 | 42.2±1.9 | <0.001 |
| VE/VCO2 at AT | 24.9±0.5 | 48.3±2.2 | <0.001 |
| PETCO2 at AT, mm Hg | 42.8±1.2 | 23.3±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.