A Study to Assess the Efficacy and Safety of 20, 40, and 80mg of Sildenafil Three Times a Day in the Treatment of Pulmonary Arterial Hypertension

You may be eligible if

• 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.