Table 3.
Cardiopulmonary exercise test
| Variable | HF Stages AB (n = 30) |
HFpEF (n = 50) |
HFrEF (n = 40) |
p-value |
|---|---|---|---|---|
| HR, beats/min @rest | 75 (70–80) | 75 (65–85) | 82 (65–90) | 0.241 |
| HR, beats/min @peak | 140 (121–150) | 110 (105–135)* | 105 (95–135)* | 0.004 |
| Chronotropic incompetence# | 8 (27) | 27 (54) | 24 (60) | 0.015 |
| SBP, mmHg @rest | 130 (120–149) | 130 (118–141) | 118 (100–135) | 0.054 |
| DBP, mmHg @rest | 80 (75–90) | 70 (65–85) | 70 (67–80) | 0.052 |
| SBP, mmHg @peak | 195 (176–205) | 165 (146–185)* | 150 (140–167)* | < 0.0001 |
| DBP, mmHg @peak | 85 (80–103) | 75 (70–90) | 78 (65–90) | 0.066 |
| Workload, W | 125 (100–150) | 65 (46–89)* | 70 (60–110)* | < 0.0001 |
| Time of effort, min | 10 (9–11) | 9 (8–10) | 9 (8–10) | 0.071 |
| RER @peak | 1.1 (1.1–1.2) | 1.1 (1.1–1.2) | 1.1 (1.0–1.2) | 0.298 |
| VO2, mL/kg/min @peak | 21.2 (17.5–22.5) | 12.7 (9.5–14.5)* | 13.8 (10.2–15.5)* | < 0.0001 |
| VE/VCO2 slope | 28 (26–32) | 38 (33–42)* | 40 (34–44)* | < 0.0001 |
| VD/VT (%) | 20 (16–23) | 23 (20–26)* | 24 (22–27)* | 0.001 |
| O2 pulse, mL/beat @peak | 11.2 (8.6–12.8) | 8.1 (6.3–10.6)* | 8.3 (7.2–10.1) | 0.002 |
| VO2/work slope, mL/min/W | 10 (9–10.5) | 7.4 (6–8.6)* | 7.5 (6.2–9.3)* | < 0.0001 |
| VO2/work flattening | 0 | 6 (12) | 5 (13) | 0.132 |
| EOV | 0 | 1 (2) | 1 (3) | 0.701 |
Values are n (%), or median (25th quartile, 75th quartile)
DBP: diastolic blood pressure; EOV: exercise oscillatory ventilation; HFpEF: heart failure with preserved ejection fraction; HFrEF: heart failure with reduced ejection fraction; HR: heart rate; MBP: mean blood pressure; RER: respiratory exchange ratio; SBP: systolic blood pressure; VCO2: carbon dioxide production; VD: Physiologic dead space; VE: minute ventilation; VO2: oxygen consumption; VT: Tidal volume
*p < 0.01 vs. Controls; ‡ p < 0.01 vs. HFpEF
#Failure to achieve ≥ 80% of the difference between age-predicted maximal HR and resting HR (HR reserve) during exercise