Risk Assessment and Emergency Management of Coronary Heart Disease at Altitude

We read with interest the excellent review by Dehnert and Bärtsch (2010) on the risk assessment of altitude exposure in patients with coronary heart disease (CHD). Sudden cardiac death (SCD) represents the second most common cause of death in the European Alps, yet some studies show favorable effects of chronic exposure to moderate altitude on cardiovascular and metabolic variables in patients with cardiovascular risk factors (Schobersberger et al., 2003), with the consequence that mountain tourists are encouraged to go to moderate altitude despite increasing age and comorbidities.

Dehnert and Bärtsch (2010) say that in patients with stable CHD at high altitude (HA) signs of myocardial ischemia occur at similar or slightly reduced cardiac work, and left ventricular contractility seems unaffected after a few days of acclimatization. They discourage CHD patients who do not engage in regular exercise at sea level to begin exercise at HA. To their valuable list of recommendations, we would like to add that the type of sport activity should also be considered. In addition, we suggest that placing public access defibrillators (PADs) at strategic points in the mountains could be beneficial.

Burtscher and Ponchia (2010) reported data from two epidemiological studies performed in the Eastern Alps in males older than 34 years and, using logistic regression analysis, identified risk factors for SCD in hikers and skiers. Participants in both groups with previous myocardial infarction, known CHD, and hypertension had a higher incidence of SCD compared with the respective healthy control groups. Other risk factors such as diabetes, hypercholesterolemia, and exercise patterns varied between hikers and skiers. The authors suggest that these differences may relate to the type of exercise (intensive short-term, static–dynamic in skiing versus prolonged, relatively low-intensity exertion in hiking) and to differing environmental conditions (colder versus warmer) and speed of altitude change (faster versus slower) between the sports. Future studies are needed to define these factors with precision.

We agree with Dehnert and Bärtsch (2010) that risk assessment of CHD patients and individual pretravel advice are key to preventing SCD at altitude. However, we would like to point out that providing an effective chain of survival, including a defibrillator, should be addressed even in mountain areas. The 2010 guidelines for cardiopulmonary resuscitation recommend the establishment of automated external defibrillator programs “in public locations where there is a reasonable likelihood of witnessed cardiac arrest” (Link et al., 2010). The International Commission for Mountain Emergency Medicine ICAR-MEDCOM also supports the introduction of PADs in busy mountain areas (Elsensohn et al., 2006). We suggest priority should be given to ski areas in the winter and mountain huts near lifts or busy trail routes and be based on an analysis of type of sport and participant's risk factors.