| Total | IPAH/HPAH | APAH | ||
| CHD | Non-CHD | |||
| Patients n | 66 | 34 | 24 | 8 |
| Patient characteristics | ||||
| Males | 23/66 (34.8) | 22/34 (64.7) | 19/24 (79.2) | 2/8 (25.0) |
| Age at treatment initiation years | 8.0 (2.9–13.7) | 7.9 (2.9–13.7) | 9.5 (1.4–15.1) | 7.6 (6.2–11.5) |
| Heart rate beats per min | 100±24.9 (n = 63) | 99±23.6 (n = 32) | 103±27.2 (n = 23) | 98±25.8 |
| Systolic blood pressure mmHg | 105±17.7 (n = 55) | 107±17.2 (n = 28) | 97±11.6 (n = 19) | 115±24.8 |
| Diastolic blood pressure mmHg | 62±12.5 (n = 55) | 63±14 (n = 28) | 58±8.1 (n = 19) | 69±13.4 |
| WHO-FC | ||||
| I or II | 13/66 (19.7) | 7/34 (20.6) | 1/24 (20.8) | 1/8 (12.5) |
| III | 32/66 (48.5) | 17/34 (50.0) | 11/24 (45.8) | 4/8 (50.0) |
| IV | 21/66 (31.8) | 10/34 (29.4) | 8/24 (33.3) | 3/8 (37.5) |
| 6MWD# m | 350±91.7 (n = 32) | 377±80.6 (n = 18) | 315±100.4 (n = 13) | 324 (n = 1) |
| Biochemical characteristics | ||||
| NT-proBNP ng·L−1 | 875 (176–3090) (n = 48) | 1391 (202–4414) (n = 24) | 854 (86–1456) (n = 17) | 497 (115–7653) (n = 7) |
| CK U·L−1 | 67 (33–125) (n = 32) | 66 (25–133) (n = 17) | 71 (39–90) (n = 10) | 106 (44–211) (n = 5) |
| CK-MB U·L−1 | 21 (9–33) (n = 31) | 20 (8–32) (n = 16) | 24 (11–42) (n = 10) | 22 (14–30) (n = 5) |
| Uric acid mmol·L−1 | 0.3±0.09 (n = 40) | 0.3±0.07 (n = 20) | 0.3±0.09 (n = 15) | 0.4±0.17 (n = 5) |
| Noradrenaline nmol·L−1 | 1.5 (0.94–2.62) (n = 23) | 2.0 (1.3–5.9) (n = 13) | 1.3 (0.8–1.95) (n = 9) | 1.0 (n = 1) |
| Adrenaline nmol·L−1 | 0.2 (0.12–0.54) (n = 22) | 0.3 (0.2–0.85) (n = 13) | 0.1 (0.05–0.18) (n = 8) | 0.13 (n = 1) |
| Detectable troponin | 11/33 (33.3) | 8/17 (47.1) | 1/11 (9.1) | 2/5 (40.0) |
| Echocardiographic characteristics | ||||
| TAPSE mm | 15 (11.3–17.0) (n = 49) | 15 (11.1–16.8) (n = 28) | 15 (9.8–18.0) (n = 14) | 16 (12.5–19.5) (n = 7) |
| RV/LV ratio | 1.0 (0.71–1.57) (n = 48) | 1.2 (0.9–1.6) (n = 27) | 0.8 (0.6–1.2) (n = 13) | 0.8 (0.6–1.7) (n = 8) |
| Presence of pericardial effusion | 6/50 (12.0) | 4/28 (14.3) | 0/14 (0.0) | 2/8 (25.0) |
| Diagnostic cardiac catheterisation | ||||
| Cardiac index L·min−1·m−2 | 2.8 (2.3–4.0) (n = 53) | 2.8 (2.0–3.5) (n = 27) | 2.7 (2.3–3.8) (n = 19) | 4.4 (2.4–4.7) (n = 7) |
| mRAP mmHg | 6 (5–8) (n = 59) | 6 (5–9) (n = 31) | 7 (5–8) (n = 21) | 5 (4–8) (n = 7) |
| mPAP mmHg | 50 (36–64) (n = 59) | 54 (36–64) (n = 31) | 49 (38–68) (n = 21) | 47 (30–61) (n = 7) |
| PVRI WU·m2 | 15.3 (8.1–26.8) (n = -53) | 18.8 (8.3–27.8) (n = 27) | 15.3 (7.1–32.7) (n = 19) | 8.5 (4.7–18.5) (n = 7) |
| SvO2 % | 63.8 (56.0–71.5) (n = 56) | 64.9 (55.2–71.4) (n = 28) | 63.0 (54.1–67.4) (n = 21) | 69.8 (59.7–76.2) (n = 7) |
| Acute response to vasodilator testing¶ | 4/47 (8.5) | 3/24 (12.5) | 1/16 (6.3) | 0/7 (0.0) |
| Medication started at treatment initiation | ||||
| Medication | ||||
| ERA | 37/66 (56.1) | 18/34 (52.9) | 18/24 (75) | 1/8 (12.5) |
| PDE5i | 20/66 (30.3) | 11/34 (32.4) | 5/24 (20.8) | 4/8 (50.0) |
| Prostanoid | 16/66 (24.2) | 10/34 (29.4) | 2/24 (8.3) | 4/8 (50.0) |
| Therapy intensity | ||||
| Monotherapy | 60/66 (90.9) | 30/34 (88.2) | 23/24 (95.8) | 7/8 (87.5) |
| Upfront dual therapy | 5/66 (7.6) | 3/34 (8.8) | 1/24 (4.2) | 1/8 (12.5) |
| Upfront triple therapy | 1/66 (1.5) | 1/34 (2.9) | 0/24 (0.0) | 0/8 (0.0) |
Data are presented as n/N (%), median (interquartile range) or mean±sd, unless otherwise stated. IPAH: idiopathic pulmonary arterial hypertension; HPAH: hereditary pulmonary arterial hypertension; CHD: congenital heart disease; APAH: associated pulmonary arterial hypertension; WHO-FC: World Health Organization functional class; 6MWD: 6-min walk distance; NT-proBNP: N-terminal pro-brain natriuretic peptide; CK: creatine kinase; TAPSE: tricuspid annular plane systolic excursion; RV: right ventricular; LV: left ventricular; mRAP: mean right atrial pressure; mPAP: mean pulmonary artery pressure; PVRI: pulmonary vascular resistance index; WU: Wood unit; SvO2: mixed venous oxygen saturation; ERA: endothelin receptor antagonist; PDE5i: phosphodiesterase-5 inhibitor. #: only in children ≥7 years old; ¶: according to Sitbon criteria (decrease in mPAP of ≥10 mmHg to an absolute mPAP ≤40 mmHg without a decrease in cardiac output).