Physical activities Peripheral vasodilatation or increased cardiac demand will put PAH patient at risk of acute cardiac failure and syncope. Thus, we traditionally advise against extreme physical activity. Patients are taught to stay active while adapting effort according to their symptoms. Nevertheless, the appropriate level of physical activity is difficult to define. To date, only few studies have evaluated to effect of cardio-respiratory rehabilitation in PAH. One of this program involved three weeks of inpatient rehabilitation followed by three month training at home with phone call supervision. No modification on cardiac hemodynamic was observed on echocardiography but 6-MWD and quality of life were improved. As proposed in ERS/ESC guidelines, more data are required before appropriate recommendations can be made [15].