Is there a risk of heart attack during a cardiac rehabilitation program?

Yes but worth it: Although there is a limited risk of a heart attack occuring during cardiac rehab, that risk is present at home climbing the stairs or crossing the street. The risk is limited because the activity is supervised, and the patient is one "panic button" away from immediate cardiac intervention. In other words, if it's going to happen, it'll happen, but at least you're in the right place if it does.

Yes, but: There is always a risk of heart attack in people who have coronary artery disease - day and night, 24x7. That said, the risk is exceptionally low in cardiac rehab. Moreover, if you're destined to have a heart attack, can you think of a better place (that is, where you could get the most immediate attention?).