Objective: To describe the clinical and epidemiological characteristics, evolution and treatment of patients with pulmonary arterial hypertension.Materials and methods: A descriptive study that included 47 patients with a primary diagnosis of pulmonary arterial hypertension. Results: The average age of the patients was 48 years and 91.49 % were females. The average follow-up was 39 months.The main types of pulmonary arterial hypertension were the one associated with congenital heart diseases (48.93 %), the one associated with connective tissue diseases (21.28 %) and idiopathic hypertension (17.02 %). Monotherapy (mainly with sildenafil) and sequential combination therapy (sildenafil plus bosentan) were used in 78.72 % and 21.28 % of the patients,respectively. During the follow-up, 70.21 % of the patients were hospitalized at least once and five patients died, resulting in a cumulative to...