Table 2. Cardiopulmonary exercise testing.
| HVS (n = 29) | control (n = 29) | p | |
|---|---|---|---|
| rest | |||
| VO2 (l/min) | 0.32 (0.25–0.40) | 0.38 (0.29–0.50) | 0.29 |
| VO2 (ml/kg/min) | 4.2 (3.4–5.8) | 4.3 (2.9–6.4) | 0.91 |
| VCO2 (l/min) | 0.26 (0.19–0.31) | 0.27 (0.21–0.36) | 0.61 |
| VE (l/min) | 10 (8–12) | 11 (7–13) | 0.96 |
| VT (l) | 0.49 (0.41–0.65) | 0.55 (0.46–0.76) | 0.53 |
| VT/BSA (l/m2) | 0.27 (0.21–0.37) | 0.29 (0.22–0.35) | 0.91 |
| fb (bpm) | 19 ± 5 | 18 ± 5 | 0.42 |
| VD/VT | 0.21 ± 0.11 | 0.22 ± 0.10 | 0.77 |
| PETCO2 (mmHg) | 27 (25–30) | 30 (28–32) | 0.05 |
| VE/VCO2 ratio | 38 (33–44) | 37 (32–40) | 0.31 |
| RER | 0.76 (0.67–0.90) | 0.69 (0.65–0.75) | 0.08 |
| HR (beat/min) | 97 ± 13 | 82 ± 13 | <0.01 |
| peak exercise | |||
| Workload (W) | 135 (111–142) | 163 (137–186) | <0.01 |
| VO2 (l/min) | 1.37 (1.30–1.72) | 2.00 (1.59–2.47) | <0.01 |
| VO2 (ml/kg/min) | 18.7 (15.8–21.6) | 24.2 (19.4–29.2) | 0.01 |
| VCO2 (l/min) | 1.38 (1.24–1.57) | 1.81 (1.56–2.15) | <0.01 |
| VE (l/min) | 55 (46–62) | 53 (48–63) | 0.69 |
| VT (l) | 1.25 (1.16–1.64) | 1.87 (1.55–2.29) | <0.01 |
| VT/BSA (l/m2) | 0.72 (0.61–0.87) | 1.01 (0.77–1.07) | <0.01 |
| fb (bpm) | 39 (34–46) | 30 (27–33) | <0.01 |
| VD/VT | 0.18 ± 0.05 | 0.13 ± 0.06 | <0.01 |
| PETCO2 (mmHg) | 27 ± 4 | 35 ± 4 | <0.01 |
| VE/VCO2 ratio | 38 (35–43) | 31 (27–34) | <0.01 |
| RER | 0.96 ± 0.1 | 0.89 ± 0.12 | 0.03 |
| HR (beat/min) | 142 ± 17 | 147 ± 20 | 0.30 |
| VE/VCO2 slope | 37 (33–43) | 27 (24–30) | <0.01 |
Data shown as mean ± SD or median (IQR). bpm = breaths per minute; BSA = body surface area; fb = breathing frequency; HR = hear rate; HVS = hyperventilation syndrome; kg = kilogram; l = liter; m2 = square meter; min = minute; ml = milliliter; mmHg = millimeters of mercury; PETCO2 = partial pressure of end-tidal carbon dioxide; RER = respiratory exchange ratio; VCO2 = carbon dioxide output; VD = dead space volume; VE = minute ventilation; VE/VCO2 = ventilatory efficiency; VO2 = oxygen consumption; VT = tidal volume; W = watts