A Study to Find Out if Selexipag is Effective and Safe in Patients With Chronic Thromboembolic Pulmonary Hypertension When the Disease is Inoperable or Persistent/Recurrent After Surgery

A Study to Find Out if Selexipag is Effective and Safe in Patients With Chronic Thromboembolic Pulmonary Hypertension When the Disease is Inoperable or Persistent/Recurrent After Surgery