Long-term effects with ambrisentan monotherapy in patients with pulmonary arterial hypertension

Objective To investigate long-term efficacy and safety of ambrisentan monotherapy in patients with pulmonary arterial hypertension(PAH).Methods Patients with PAH who received 2.5 mg or 5 mg of ambrisentan once daily between July 10,2011 and August 30,2012for at least 6 months were enrolled.The efficacy endpoints were changes in exercise capacity,World Health Organization(WHO)functional class and N-terminal probrain natriuretic peptide(NT-pro BNP)level,echocardiographic parameters.The safety endpoint was the safety of long-term ambrisentan administration,as defined by