Study Performed at Various Medical Centers to Learn More About Survival and Expected Course of Pulmonary Arterial Hypertension, a Type of High Blood Pressure in the Lungs Related to the Narrowing of the Small Blood Vessels in the Lungs (START)

Inclusion Criteria:

• Consecutive newly diagnosed patients by Right heart catheterization (RHC) from 01-Jan-2012 to 31-Dec-2017, belonging to one of the following of Group 1 PAH subgroups: Idiopathic (IPAH), or Heritable (HPAH), or Drug or toxin induced, or Associated (APAH) with one of the following: Connective tissue disease; Congenital heart disease with simple systemic to pulmonary shunt at least 1 year after surgical repair; Portal Hypertension or HIV infection.
• Diagnosis of PAH by RHC exhibiting a mean pulmonary artery pressure (MPAP) ≥ 25 mmHg and a pulmonary artery wedge pressure (PAWP) ≤15 mmHg at normal or reduced cardiac output, according to European Society of Cardiology and European Respiratory Society (ESC/ERS) 2009 guidelines or MPAP ≥ 25 mmHg and a PAWP ≤15 mmHg and a pulmonary vascular resistance (PVR) > 3 WU according to ESC/ERS 2015 guidelines.
• Patients with at least one year documented follow up or that have died or received transplant before 1 year of follow up after baseline RHC and that have initiated treatment with a PAH-targeted medication.

Exclusion Criteria:

• Patients with severe concomitant left heart disease (left ventricular ejection fraction <35%).
• Patients with restrictive lung disease (Forced vital capacity (FVC) <60% predicted) other than connective tissue disease or obstructive lung disease (forced expiratory volume (FEV) <60% predicted, with FEV1/FVC<70%).
• Clinical or radiological evidence of Pulmo-Veno-Occlusive Disease (PVOD) or Pulmonary Capillary Haemangiomatosis (PCH).
• Hypertrophic obstructive cardiomyopathy.
• Severe proven or suspected coronary artery disease.
• Congenital or acquired valvular or myocardial disease if clinically significant apart from tricuspid valvular insufficiency due to pulmonary hypertension.
• Underlying medical disorders at baseline with an anticipated life expectancy below 2 years (e.g. active cancer disease with localized and/or metastasized tumor mass) or Clinical relevant hepatic dysfunction (Child-Pugh B and C) or Renal insufficiency (glomerular filtration rate <30 mL/min).
• Diagnosis of a pulmonary hypertension from WHO groups 2, 3, 4 or 5.