A Study of Clinical Efficacy of Sildenafil in Patients with Primary Pulmonary Hypertension

Background: Primary pulmonary hypertension is a disorder with limited treatment options and poor outcome. Sildenafil, a pulmonary vasodilator, is likely to be beneficial in primary pulmonary hypertension. We studied the clinical efficacy of sildenafil in patients with primary pulmonary hypertension.

Methods And Results: A registry of patients with primary pulmonary hypertension has been maintained in our hospital since January 1999. Of a total of 60 patients. 29 (M:16, F:13) consented to try sildenafiL. New York Heart Association functional class, six-minute walk test and Doppler echocardiographic evaluation of pulmonary artery pressure was done before and after treatment with sildenafil. Sildenafil was initiated at a dose of 25 mg thrice a day and increased up to 100 mg thrice a day as tolerated. There was a significant improvement in the functional class. The six-minute walked distance increased from 297.07+/-130.69 m at baseline to 427.68+/-85.35 m after 3 months of sildenafil therapy (p<0.0003). The mean of the pulmonary artery systolic pressure before starting sildenaffil was 109.26+/-24.15 mmHg (mean+/-SD) and it decreased to 95.15+/-24.64 mmHg (p<0.008). While 19 of the 31 historical controls in whom sildenafil was not given died during follow-up (11-44 months), only 1 of the 29 patients given sildenafil died (in an accident) during follow-up (5-20 months).

Conclusions: Sildenafil, a pulmonary vasodilator, has a beneficial effect in patients with primary pulmonary hypertension in improving the functional class, six-minute walked distance and in decreasing the pulmonary artery pressures.