Original Research: Pulmonary Vascular DiseasePulmonary Arterial Hypertension in the Southern Hemisphere

BACKGROUNDPulmonary arterial hypertension (PAH) is a rare and ultimately fatal disorder of the pulmonary vasculature. There is increasing interest in the worldwide characteristics of patients with PAH, although data coming from the Southern Hemisphere remain scarce. The objective of this study was to describe a cohort of incident patients with PAH from a large reference center in Brazil.METHODS: All consecutive patients who received a diagnosis of PAH by right-sided heart catheterization between 2008 and 2013 were included in the study.RESULTS: A total of 178 patients with newly diagnosed PAH were enrolled in the study (mean age, 46 years; female/male ratio, 3.3:1; 45.5% in New York Heart Association functional class III or IV). Idiopathic PAH (IPAH), connective tissue disease (CTD), and schistosomiasis-associated PAH (Sch-PAH) accounted for 28.7%, 25.8%, and 19.7% of all cases, respectively. The patients were treated with phosphodiesterase type 5 inhibitors (66%), endothelin receptor antagonists (27%), or a combination of both (5%). For the PAH group as a whole, the estimated survival rate 3 years after diagnosis was 73.9%. The prognosis for the patients with CTD was worse than that for the patients with IPAH and Sch-PAH (P = .03).CONCLUSIONS: The distribution of PAH causes and the baseline characteristics in our registry clearly differ from the previously published European and US-based registries. These differences highlight the importance of regional registries and also raise questions regarding the need to better account for such differences in future clinical trials.