Objective: The objective was to evaluate the short- term efficacy of oral Sildenafil in symptomatic patients of Pulmonary Arterial Hypertension (PAH), both primary and secondary.

Materials and Methods: The study involved 40 patients of PAH (n=18 for primary, n=22 for secondary PAH) of both sexes & between 12 to 75 years of age, having pulmonary arterial pressure (PAP) of more than 30 mm of Hg with NYHA class II&III symptoms. Subjects received sildenafil 50 mg 8 hourly orally, or a matching placebo for six weeks each, in a randomized, double-blind, crossover design. A run-in period of two weeks was permitted at the beginning and between two therapies.  At the end of each therapy, the patients were evaluated for the study parameters i.e. distance covered in 6-minute walk test, PAP by doppler echocardiography and quality of life (QOL) assessed by ‘Minnesota Living with Heart-failure Questionnaire’. Statistical analysis was done using paired & un-paired ‘t’ test (p<0.05).

Results: The mean distance covered in 6 minute walk test improved from 283.33 ± 56.81m to 422.17 ± 79.09m (p<0.0001) for primary and from 353.23 ± 56.61m to 406.09 ± 59.33m (p<0.0001) for secondary PAH after 6 wks treatment with sildenafil. PAP decreased from 85.94 ± 11.81 mm Hg to 38.78 ± 6.90 mm Hg (p<0.0001) for primary and from 52.14 ± 10.26 mm Hg to 41.68 ± 9.09 mm Hg for secondary PAH. Sildenafil shows very significant improvement in functional capacity by lowering the QOL score in both primary and secondary PAH (p<0.0001 and p<0.0001 respectively). No serious side effects of drug were observed in the study. 

Conclusion: Sildenafil significantly improves exercise capacity and quality of life and decreases the PAP in both primary and secondary PAH. Therefore, oral sildenafil may be recommended as first-line or adjunctive treatment in PAH, particularly primary one.

Keywords: Sildenafil, placebo, primary and secondary pulmonary arterial hypertension.

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Ananya Pal

Assistant Professor, Department of Pathology, NRS Medical College, Kolkata

Address: Sanjeeva Garden, Unit No. 33DL, Thakdari road, Newtown, Kolkata-700156, West Bengal, India