Heart disease and high altitudes: Safe to travel?

Q. I had a heart attack about five years ago, but I have no symptoms now. I am planning a vacation where I will be spending several days over 8,000 feet. Do I need to take any precautions?

A. You should be able to take this trip if you prepare and don't overtax yourself. Before any long-distance vacation, especially one that involves strenuous outdoor activity, you should see your doctor for a general checkup and review of your heart condition. Even if you have had no symptoms for years, there is still reason for caution in this case. At high altitudes, the air contains less oxygen. In response, you will begin to hyperventilate (breathe rapidly) to maintain sufficient oxygen levels in the blood. Also, your heart will beat 15 to 20 beats per minute faster, and your blood pressure will rise somewhat. A general estimate is that any activity at an 8,000-foot altitude will require an additional 15% to 20% in effort compared with sea level, straining your cardiovascular system. Walking on flat ground at 8,000 feet will feel like a slow jog.