[Effects of ambrisentan in treatment of pulmonary arterial hypertension: a pilot study with 15 patients].

OBJECTIVE

To investigate the preliminary efficacy and safety of ambrisentan, a selective endothelin receptor antagonist, in patients with pulmonary arterial hypertension (PAH).

METHODS

A total of 15 patients with PAH, including 10 patients with idiopathic PAH and 5 patients with associated connective-tissue disease, received 2.5 mg or 5 mg of ambrisentan once daily for 12 weeks. Before and after 12 weeks treatment, 6-minute walk test (6-MWD), WHO functional classification (WHO FC) and N-terminal pro-brain natriuretic peptide (NT-proBNP) were measured.

RESULTS

After 12 weeks treatment, the 6-MWD was significantly increased [(376.5 ± 108.2) m vs.(460.3 ± 95.7) m, P = 0.021] and the systolic pulmonary artery was significantly decreased [(85.0 ± 33.3) mm Hg (1 mm Hg = 0.133 kPa)vs. (70.5 ± 30.5) mm Hg,P = 0.015] and NT-proBNP was significantly reduced [892.0 (99.0-2245.0) ng/L vs. 205.0 (56.0-534.0) ng/L, P = 0.026] than before treatment. WHO FC was improved in 4 patients after 12 weeks treatment. No patient was withdrawn from this study for safety reasons.

CONCLUSIONS

Ambrisentan treatment can effectively improve the exercise capacity, and reduce systolic pulmonary artery pressure and NT-proBNP in PAH patients. Ambrisentan use is safe and could be well tolerated in Chinese PAH patients.