PH is a serious disease with a dismal prognosis and impaired quality of life when left untreated. Reliable patient centered and prognostically relevant outcome measures are highly warranted in the field of PH. With this prospective cohort study the investigators intend to gain important information on the course of the disease and knowledge on the value of different new and already established outcome parameters.

PH is a serious disease with a dismal prognosis and impaired quality of life when left untreated. Advances in medical therapy have improved survival according to recent registries, but are associated with high healthcare costs. Most treatment trials and clinical follow-up assessments rely on the 6 minute walk distance as main outcome parameter although submaximal exercise performance reflects only one disease aspect.

Reliable patient centered and prognostically relevant outcome measures are highly warranted in the field of PH. With this prospective cohort study the investigator intend to gain important information on the course of the disease and knowledge on the value of different new and already established outcome parameters. New outcomes to be assessed will be home based activity monitoring, novel physiological measures, namely cerebral and muscle tissue oxygenation at rest and during exercise testing, stair ascent on mechanograph, sit to stand test and several serum markers and micro-RNA. All these assessments will be compared with hard endpoints events (death, lung-transplantation, hospitalization for PH), and with traditional outcome measures such as NYHA functional class, 6 minute walk distance, generic quality of life, cardiopulmonary exercise tests, sleep studies, health preference (utility) and cognitive function.

Inclusion Criteria:

• Patients with precapillary pulmonary hypertension
• Adult male and female patients of all ages referred to our center for evaluation/treatment of PH
• Written informed consent by the subject after information about the research project

Exclusion Criteria:

• Patients with severe concomitant left heart disease (left ventricular ejection fraction <40%).
• Patients with restrictive lung disease (FVC<60% predicted); obstructive lung disease (forced expiratory volume (FEV) <60% predicted, with FEV 1/FVC<70%).
• Patients with any other disease limiting their ability to move (skeletal disease, neurological disease, etc.)

Patients with precapillary pulmonary hypertension classified according to WHO