Outcome Study Assessing a 75 Milligrams (mg) Dose of Macitentan in Patients With Pulmonary Arterial Hypertension

Inclusion Criteria: * Target population: greater than or equal to (\>=) 18 (or the legal age of consent in the jurisdiction in which the study is taking place) years of age * Target population: Symptomatic Pulmonary Arterial Hypertension (PAH) in World Health Organization Functional Class (WHO FC) II, III, or IV * Target population: PAH subtype falling in one of the below classifications: Idiopathic; Heritable; Drug- or toxin-induced; Related to: Connective tissue disease, HIV infection, Portal hypertension, and Congenital heart disease with small/coincidental cardiac defect with systemic-to-pulmonary shunt (for example atrial septal defect, ventricular septal defect, patent ductus arteriosus, atrioventricular septal defect) which does not account for the elevated pulmonary vascular resistance (PVR) or persistent PAH documented by an Right heart catheterization (RHC) \>= 1 year after simple systemic-to pulmonary shunt repair * PAH diagnosis confirmed by hemodynamic evaluation at rest at any time prior to screening: Mean pulmonary artery pressure (mPAP) greater than (\>) 20 millimeters of mercury (mm Hg), and; Pulmonary artery wedge pressure (PAWP) or left ventricular end diastolic pressure (LVEDP) less than or equal to (\<=) 15 mm Hg, and PVR \>= 3 Wood Units (that is, \>= 240 dyn\*sec/cm\^5) * Able to perform the 6-minute walking test (6MWT) with a minimum distance of 50 meters (m) and maximum distance of 440m at screening. Participants able to walk more than 440m at screen…