Mountain air or heart risk? trial asks if high altitude is safe for aortic stenosis patients.

Copied word for word from the study's registry entry, so the wording is the study team's rather than ours.

Inclusion Criteria: Group 1: * Moderate or severe aortic stenosis (aortic valve area (AVA) ≤1.5 cm2) * NYHA class I * LVEF \> 50% * Aortic stenosis staging classification Stage 0 or 1 * Written informed consent Group 2: * Aortic stenosis s/p aortic valve replacement within 1 year * NYHA class I * LVEF \> 50% * Aortic stenosis staging classification Stage 0 or 1 * Written informed consent Group 3: * NYHA class I * LVEF \>50% * No evidence of valvular heart disease * Age \> 65 years * Written informed consent Exclusion Criteria: * NYHA class \> I (all groups) * History of cardiac decompensation requiring hospitalization (all groups) * Uncontrolled arterial hypertension (\>180/100 mmHg at rest) (all groups) * Other Cardiomyopathies w/ normal LVEF (dilatative, hypertrophic, infiltrative CMP) (all groups) * Signs of exercise-induced ischemia (ST-segment depression \> 2 mV), hemodynamic instability (drop in systolic blood pressure \> 20 mmHg and systolic blood pressure ≤ 100 mmHg), or ventricular arrhythmias (\> 5 beats) during cardiopulmonary stress exercise testing (CPET) at Bern (540 meters) (all groups) * Chronic obstructive pulmonary disease with a forced expiratory volume in 1 second (FEV1) \<60% of the predicted (all groups) * Known pulmonary hypertension with a pulmonary artery systolic pressure \>50 mmHg or high probability of pulmonary hypertension as assessed in TTE (all groups) * NT-pro BNP levels \> 900 pg/ml (all groups) * Aortic stenosis staging classification \> Stage 1 (group 1 and 2) * History of advanced stages of acute mountain sickness defined as high altitude pulmonary (HAPE) or cerebral (HACE) edema (all groups) * Transvalvular gradient across the aortic valve ≥60 mmHg, Vmax \>5 m/s (group 1) * Vmax progression ≥0.3 m/s/year (group 1) * Transvalvular gradient across the aortic valve ≥20 mmHg (group 2) * Evidence of valvular heart disease or coronary artery disease (group 3) * History of rhythm disturbances (other than premature ventricular contraction (PVC) (group 3) * Right ventricular dysfunction, defined as TAPSE \< 17 mm, s'DTI \< 9 cm/sec (all groups)