Included patients had primary pulmonary arterial hypertension, pulmonary hypertension
secondary to connective tissue disease, or pulmonary hypertension with surgical repair at
least 5 years previously; a mean pulmonary artery pressure greater than or equal to 25 mmHg
and a pulmonary artery wedge pressure of less than or equal to 15 mmHg at rest, via right
heart catheterisation within 21 days prior to randomisation; and a baseline 6-Minute Walk
test distance of 100 m to 450 m.
Subjects with congenital heart disease, pulmonary hypertension due to thromboembolism, HIV,
chronic obstructive airway disease, congestive heart failure or schistosomiasis; subjects
with significant (ie > 2+) valvular disease other than tricuspid regurgitation or pulmonary
regurgitation; and acutely decompensated heart failure within the previous 30 days;
subjects with pulmonary hypertension secondary to any other etiology other than those
specified in the inclusion criteria.