Acute Myocardial Infarction at High Altitude

To the Editor. —Myocardial infarction at high altitude is uncommon, and the effect of high altitude on coronary syndromes is controversial.¹ In the last 15 years, trekkers with acute coronary syndromes have been rarely, if ever, reported by physicians at high-altitude clinics (J.A.L., unpublished data, 1997).

—A 29-year-old athletic man developed retrosternal chest pressure while climbing in the Khumbu Icefall of Mount Everest (5900 m), where the oxygen tension is approximately 75 mm Hg. He had experienced an episode of chest tightness 2 weeks earlier on arrival at the base camp (5500 m). The patient had no prior episodes of chest pain; had

no history of tobacco use, recreational drug use, hypercholesterolemia, diabetes, migraines, or Raynaud phenomenon; and had no family history of premature coronary artery disease. The patient was taking acetazolamide for the