What does high altitude do for ischemic heart disease, is there any difference?

Stress on heart. Pts who go to high altitudes find that there is less availbla oxygen for them to do such things as execise etc. Over time the body adapts by making more red blood cells .And they wont feel so fatigued or short of breathe with activities. But this adaptation takes time. A pt with ischemic heart disease doesnt always have the reserve during the transition and agina or even a heart attack can occur.