Long-term outcomes of treatment with bosentan in pulmonary hypertension

OBJECTIVE: Treatment with bosentan improves exercise capacity in patients with pulmonary hypertension. Few studies have assessed treatment with this drug over long periods. The aim was therefore to assess long-term treatment with bosentan. PATIENTS AND METHODS: A group of 22 functional class III patients-18 women and 4 men, mean age, 45.5 years (range, 19-77 years)-with pulmonary hypertension were treated with bosentan between April 2002 and June 2005. Pulmonary hypertension was idiopathic in 10 patients. In the remaining patients, etiologies were associated with compensated heart failure (n=4), scleroderma (n=4), peripheral embolism (n=3), and portal hypertension (n=1). Clinical and hemodynamic variables and their changes between baseline and the end of study were analyzed. RESULTS: The mean duration of follow-up of the patients was 15.7 months (range, 12.6-31.8 months). Functional class improved or stabilized after 3 months of treatment in 21 (95%) and after 1 year in 14 (64%). At 3 months, the distance covered in the 6-minute walk test increased by a mean of 64.5 m, an improvement that was maintained at 6, 12, and 18 months. Treatment was interrupted in 4 patients (18%). Reasons for discontinuation were death in 2 patients, deterioration in 1 patient, and intolerance of the medication in 1 patient. Treatment was ineffective for 4 patients (18%). No patient experienced notable liver toxicity. CONCLUSIONS: The results of this study suggest that treatment with bosentan is associated with long-term improvement in clinical variables and exercise capacity in approximately two thirds of the patients with pulmonary hypertension.