Pulmonary hypertension (PHT) is a rare entity that is difficult to treat. Prognosis is poor. Sildenafil, a selective inhibitor of type 5 phosphodiesterase, has been proposed among the many treatments available for primary and secondary pulmonary hypertension. We report our experience with an infant with pulmonary hypertension due to congenital mitral stenosis and persistent ductus arteriosus, who developed congestive cardiac failure with persistent PHT despite surgical correction. Conventional treatment was unsuccessful and the patient was treated with sildenafil. The clinical course was satisfactory, allowing extubation and withdrawal of vasoactive drugs; pulmonary and left atrial pressure decreased and the patient was discharged. She is currently being treated on an outpatient basis with oral sildenafil and shows satisfactory hemodynamic status. We review alternatives to conventional treatments for pulmonary hypertension with special reference to pediatrics.