[Endothelin receptor antagonists in pulmonary arterial hypertension]

Endothelin-1 (ET-1) is the most potent vasoconstrictor agent resulting in increased pulmonary vascular resistance and has proliferative effects on the vascular smooth muscle cells. Evidence for the relationship between increased blood levels of ET-1 and disease severity in pulmonary arterial hypertension (PAH) established the basis of specific approach targeted to endothelin pathway in PAH. The results of the observational studies and randomized controlled trials revealed that endothelin receptor antagonists (ERAs) compared with conventional medication may improve exercise tolerance and functional status, quality of life, right ventricular function and pulmonary hemodynamics and may lengthen the time to clinical worsening and survival in patients with PAH. Recently, the indications for ERAs in PAH seem to expand from class III and IV to class II symptomatology. In this review, we aimed to outline therapeutic benefits, drug-to-drug interactions and safety profile of different ERAs as specific agents of monotherapy or as a component of combination therapy in patients with PAH from the perspective of the evidence-based medicine.