Introduction and objectives: Pulmonary arterial hypertension carries a poor prognosis in both adult and pediatric patients. Current understanding of the mechanisms underlying pulmonary arterial hypertension has enabled the rapid development of appropriate drugs, such as endothelin receptor antagonists and 5-phosphodieste-rase inhibitors, that can be administered orally and which are generally well tolerated. The aims of the present study were to evaluate functional class and exercise capacity following long-term treatment with sildenafil or bosentan in patients with idiopathic pulmonary arterial hypertension and Eisenmenger's syndrome and to compare results in the two groups.
Methods: Seven patients were included in the pulmonary arterial hypertension study, and diagnoses of idiopathic pulmonary arterial hypertension were confirmed. Five patients were treated with sildenafil, while two received bosentan. The five patients with a non-restrictive ventricular septal defect and pulmonary arterial hypertension were treated with sildenafil. In one patient, bosentan was added to the sildenafil.
Results: Both sildenafil and bosentan significantly improved exercise capacity in patients with idiopathic pulmonary arterial hypertension. The treatment effect was less in those with Eisenmenger physiology. Although the improvement in World Health Organization functional class was greater in patients with idiopathic pulmonary arterial hypertension, it was significant in both groups.
Conclusions: Long-term treatment with sildenafil and bosentan improved both exercise capacity and functional class in patients with idiopathic pulmonary arterial hypertension and in those with hypertension due to congenital heart disease. The changes were more marked in patients with idiopathic pulmonary arterial hypertension.