ECG changes at rest and during exercise in lowlanders with COPD travelling to 3100 m

Background: The incidence and magnitude of cardiac ischemia and arrhythmias in patients with chronic obstructive pulmonary disease (COPD) during exposure to hypobaric hypoxia is insufficiently studied. We investigated electrocardiogram (ECG) markers of ischemia at rest and during incremental exercise testing (IET) in COPD-patients travelling to 3100 m. Study design and methods: Lowlanders (residence <800 m) with COPD (forced volume in the first second of expiration (FEV1) 40-80% predicted, oxygen saturation (SpO2) ≥92%, arterial partial pressure of carbon dioxide (PaCO2)