| Better prognosis | Determinants of prognosis | Worse prognosis |
| No | Clinical evidence of right ventricle failure | Yes |
| Slow | Rate of progression of symptoms | Rapid |
| No | Syncope | Yes |
| I, II | WHO FC | IV |
| Longer (>500 m)# | 6MWT | Shorter (<300 m) |
| Peak O2 consumption >15 mL·min−1·kg−1 | Cardio-pulmonary exercise testing | Peak O2 consumption <12 mL·min−1·kg−1 |
| Normal or near normal | BNP/NT-proBNP plasma levels | Very elevated and rising |
| No pericardial effusion; TAPSE¶ >2.0 cm | Echocardiographic findings¶ | Pericardial effusion; TAPSE¶ <1.5 cm |
| Pra <8 mmHg and CI ≥2.5 L·min−1·m−2 | Haemodynamics | Pra >15 mmHg or CI ≤2.0 L·min−1·m−2 |
WHO FC: World Health Organization functional class; 6MWT: 6-min walk test; BNP: brain natriuretic peptide; NT-proBNP: N-terminal pro-B-type natriuretic peptide; TAPSE: tricuspid annular plane systolic excursion; Pra: right atrial pressure; CI: cardiac index. #: depending on age; ¶: TAPSE and pericardial effusion have been selected as they can be measured in the majority of patients. Reproduced from [9] with permission from the publisher.