Table 3. Ventilatory, cardiovascular, metabolic, and perceptual responses at peak cardiopulmonary exercise test (CPET) and in the six-minute step test (6MST) in heart failure with reduced ejection fraction (HFrEF) patients.
| Variables | 6MST | CPET | P |
|---|---|---|---|
| Steps, n | 94±30 | - | - |
| Workload, watts | - | 77±31 | - |
| V̇E, L/min | 42±17 | 46±14 | 0.57 |
| RR, bpm | 31±7 | 33±6 | 0.25 |
| V̇O2, mL/min | 1025±385 | 1034±311 | 0.89 |
| V̇O2, mL·kg-1·min-1 | 12±3 | 12±3 | 0.79 |
| V̇O2, % pred | 58±24 | 60±21 | 0.10 |
| V̇CO2, L/min | 1031±387 | 1136±377 | 0.14 |
| RER | 0.99±1 | 1.05±1 | 0.02 |
| SBP, mmHg | 154±17 | 201±25 | <0.01 |
| DBP, mmHg | 93±11 | 112±14 | <0.01 |
| HR, bpm | 113±19 | 116±17 | 0.52 |
| SpO2, % | 94±2 | 95±2 | 0.73 |
| Symptoms (Borg scale) | |||
| Dyspnea (0-10) | 3±2 | 4±2 | 0.74 |
| Leg Fatigue (0-10) | 2±2 | 3±2 | 0.16 |
V̇E: ventilation; RR: respiratory rate; V̇O2: oxygen uptake; V̇CO2: carbon dioxide production; RER: respiratory exchange ratio; SBP: systolic blood pressure; DBP: diastolic blood pressure; SpO2: oxygen saturation. Data are reported as mean and standard deviation (Student's t-test).