[The heart patient at high altitude: not just thin air]

The exposure to high altitude, with its inherent hypobaric hypoxia, elicits transient compensatory physiological responses of the cardiovascular and respiratory system which, however, do not preclude a safe sojourn at least up to 3500 m to the vast majority of well compensated patients with heart disease on stable drug therapy. Existing scientific statements of the European and American Societies of Cardiovascular and High-Mountain Medicine have released specific and helpful recommendations, though mostly based on expert consensus rather than solid evidence. The risk of cardiac events has been recorded only during sports activities, does not seem to depend on altitude and is similar to what is observed during intense exercise at sea level. Besides altitude itself, other aspects of the mountain environment should be considered, such as lower temperature, wind and dehydration which all require careful planning and equipment typical of the alpine sports. The distance of most mountain areas from medical centers able to provide effective care in time-dependent emergencies, and the lack in most cases of dedicated protocols, should also be considered as an important, most likely the most important limiting factor in high-risk patients.