Pulmonary arterial hypertension (PAH) is a rare disease characterized by adverse remodeling of the arterial tree leading to increased vascular resistance with subsequent increase in right ventricular afterload and eventual development of heart failure. The nonspecific clinical manifestations and lack of knowledge of pathology lead to a poor prognosis associated with delay in diagnosis and initiation of treatment. The most recent recommendations focus on optimizing the early differential diagnosis with other causes of pulmonary hypertension to initiate appropriate treatment based on the mortality risk estimation. In the last years, with the improvement in the diagnostic process, the emergence of new specific treatments, and the creation of specialized referral units for this pathology, the prognosis, and quality of life of patients with PAH have improved significantly.