Table 2. Parameters with established importance for assessing disease severity, stability and prognosis in pulmonary arterial hypertension.

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	NYHA/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

NYHA/WHO FC: New York Heart Association/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; P_ra: 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 [13] with permission from the publisher.