Altitude Related Adverse Health Effects (ARAHE) in Patients With Precapillary Pulmonary Hypertension During 30h Exposure to 2500m

The interest of journeys to high altitude regions for recreational or professional purposes is increasing, also among potentially vulnerable groups including patients with chronic cardiopulmonary diseases such as pulmonary hypertension (PH). In Switzerland and many other regions worldwide, many settlements and alpine resorts are at altitudes above 1500m and alpine tourism is an important social and economic sector. However, the hypoxic environment at altitude may induce altitude related adverse health effects (ARAHE), including hypoxemia, symptoms of acute mountain sickness (AMS), reduces exercise capacity and increases the pulmonary arterial pressure, which is of particular relevance for patients with chronic hypoxemic respiratory diseases including PH. On the other hand, advances in disease-targeted medical combination therapies renders PH to the chronic disease groups with many patients surviving for many years with a relatively good quality of live, exercise capacity and low symptom burden. However, data on ARAHE and the exercise capacity of patients with pre-existing PH at altitude is scarce, so that current expert-based guidelines discourage altitude travel for patients with PH. However, we previously showed that the majority of stable PH-patients tolerates normobaric hypoxia or a short trip to 2500m well. With this project we aim to get profound clinical and pathophysiological insights into the effects of the hypobaric hypoxic environment at altitude during an overnight stay up to 30 hours on the incidence of ARAHE needing oxygen therapy, exercise capacity, pulmonary hemodynamics and sleep in patients with precapillary PH. We hope that this new valuable data will provide a basis to better counsel PH-patients for potential risk of altitude sojourns.