Table 4– Clinical probability of pulmonary arterial hypertension (PAH) diagnosis and suggested diagnostic work-up according to the likelihood of the presence of pulmonary hypertension (PH) by Doppler echocardiography (table 2), occurrence of symptoms and risk factors, and associated conditions (table 3)

PH likelihood by echocardiography	Symptoms	Risk factors/AC	PAH probability	Work-up
Unlikely	No	Yes/no	Low	No
	Yes	Yes	Low	Echocardiographic follow-up
	Yes	No	Low	Other causes
Possible	No	No	Intermediate	Echocardiographic follow-up
	Yes	Yes	Intermediate	Right-heart catheterisation
	Yes	No	Intermediate	Echocardiographic follow-up^#
Likely	Yes	Yes/no	High	Right-heart catheterisation
Likely	No	Yes/no	High	Right-heart catheterisation

AC: associated conditions. ^#: consider also other causes and, if symptoms at least moderate, also right heart catheterisation.