Clinical characteristics and baseline haemodynamic parameters of the patients studied
| Parameter | Total | Responders to iloprost | Nonresponders to iloprost | p-value |
| Subjects n | 74 | 10 | 64 | |
| Clinical features | ||||
| Age yrs | 33.2±12.1 | 22.6±9.1 | 34.5±11.8 | 0.008 |
| Male/female n | 16/58 | 3/7 | 13/51 | 0.554 |
| WHO class II/III n | 35/39 | 9/1 | 26/38 | 0.002 |
| BSA m2 | 1.6±0.2 | 1.5±0.2 | 1.7±0.2 | 0.103 |
| Sa,O2 % | 91.2±7.9 | 92.4±11.3 | 91.0±7.5 | 0.656 |
| Sv,O2 % | 62.0±12.3 | 73.5±9.4 | 60.7±12.0 | 0.008 |
| 6MWD m | 390±106 | 438±80 | 384±108 | 0.178 |
| Biochemical indicators | ||||
| UA μmol·L−1 | 356±110 | 323±50 | 359±114 | 0.419 |
| ET-1 fmol·L−1 | 1.0±0.6 | 0.6±0.2 | 1.0±0.6 | <0.001 |
| BNP fmol·L−1 | 1273±1137 | 718±310 | 1333±1178 | 0.175 |
| Haemodynamic variables | ||||
| fC beats·min−1 | 87.3±14.2 | 80.7±13.9 | 88.0±14.1 | 0.196 |
| Ppcw# mmHg | 6.7±3.7 | 6.4±4.6 | 6.8±3.6 | 0.772 |
| P̄pa mmHg | 61.1±17.6 | 48.4±10.5 | 62.6±17.7 | 0.029 |
| P̄sa mmHg | 83.8±11.7 | 77.6±5.2 | 84.6±12.1 | 0.115 |
| Pra mmHg | 5.3±5.1 | 3.1±1.9 | 6.8±5.6 | 0.001 |
| Rtp Wood U | 17.3±9.7 | 11.4 ± 5.8 | 18.0±9.9 | 0.088 |
| Rsv Wood U | 21.4±8.8 | 16.7±5.0 | 21.9±9.0 | 0.139 |
| CI L·min−1·m−2 | 2.6±1.2 | 2.9±1.4 | 2.6±1.2 | 0.439 |
Data are presented as mean±sd, unless otherwise stated. WHO: World Health Organization; BSA: body surface area; Sa,O2: arterial oxygen saturation; Sv,O2: mixed venous oxygen saturation; 6MWD: 6-min walk distance; UA: uric acid; ET: endothelin; BNP: brain natriuretic peptide; fC: cardiac frequency; Ppcw: pulmonary capillary wedge pressure; P̄pa: mean pulmonary arterial pressure; P̄sa: mean systemic arterial pressure; Pra: right arterial pressure; Rtp: total pulmonary resistance; Rsv: systemic vascular resistance; CI: cardiac index. #: Ppcw could not be successfully measured in eight patients at the first evaluation because of a markedly enlarged right atrium and severe tricuspid regurgitation, but these eight patients were identified as having a Ppcw <15 mmHg on repeated right heart catheterisation with the aid of a guidewire with a diameter of 0.025 inches (Cordis Co., Ltd, Johnson & Johnson, Miami Lakes, FL, USA) 6–12 months later.