Correlation of LONGterm Wrist ACTigraphy Recorded Physical Performance & 6-minute Walk Distance in Patients With Pulmonary Arterial Hypertension

The objective of the study is to monitor physical activity longitudinally with a wrist activity tracker specifically in PAH patients newly initiating ERA therapy and to assess the correlation with the 6MWD at different time points. Further objectives are to assess the correlation of physical activity measured with the tracker and other parameters for clinical evaluation and right ventricular function assessment (i.e. Biomarkers, WHO Functional class, hospitalization due to PAH, Echochardiography and Quality of Life) as well as sleep efficacy in PAH patients newly initiating ERA therapy.