Resting and exercise values in normal subjects and primary pulmonary hypertension (PPH) patients categorised according to severity of reduction in cardiopulmonary exercise test (CPET) aerobic capacity

ValuesNormal# (n=20)Mild PPH (n=3)Moderate PPH (n=14)Severe PPH (n=22)Very Severe PPH (n=14)
Peak VO2 % predicted range82–13265–7950–6435–49<35
Peak VO2 % predicted101±1970±458±442±527±4
Peak VO2 mL·min−1·kg−129.5±6.614.5±3.312.5±2.211.2±2.68.1±1.7
AT % predicted104±1685±775±1057±941±7
AT mL·min−1·kg−116.3±3.910.4±2.39.7±1.38.7±2.26.8±1.3
Peak O2 pulse % predicted108±2586±1173±856±1139±5
Peak HR % predicted96±1383±1280±877±1270±13
ΔVO2/ΔWR mL·min−1·W−19.6±0.98.3±0.57.0±1.56.0±1.05.6±1.3
VE/VCO2 at AT % predicted99±12142±22149±21161±25219±76
VE/VCO2 at AT absolute29±443±645±746±862±20
VE/VCO2 slope % predicted88±11164±49148±27141±32215±123
VE/VCO2 slope absolute25±349±1445±940±1060±32
Peak VE % MVV70±1563±1954±947±1143±16
MRT s12±1034±937±1447±1364±15
mPAP mmHg48±1763±1470±1857±17
CO L min−15.1±1.14.4±1.43.5±1.03.8±1.2
PVR mmHg·L−1·min−18±415±818±514±6
NYHA symptom class2.0±0.42.5±0.52.8±0.63.3±0.4

VO2: oxygen uptake; AT: anaerobic threshold; HR: heart rate; WR: work rate; VE: minute ventilation; VCO2: carbon dioxide production; MVV: maximum voluntary ventilation; MRT: mean response time of VO2 during unloaded cycling; mPAP: mean pulmonary arterial pressure; CO: cardiac output; PVR: pulmonary vascular resistance; NYHA: New York Heart Association; VE/VCO2 slope: slope of the relationship between VE and VCO2; VE/VCO2 at AT: ratio of ventilation to carbon dioxide output at AT; ΔVO2/ΔWR: increase in oxygen uptake per increase in work rate. #: each CPET parameter is significantly different for all PPH patients compared to that of normal control subjects (p<0.001). Data is reproduced from [20] with permission.