I had a mild heart attack 3 yrs ago. now i am having thyroid issues slow hr. given levothyroxine na synthroid....is this drug dangerous for me. .025mg?

No: Have a full thyroid panel done including ft4, ft3, rt3, tsh, tpo & tgab. Then it is possible to determine if the dose or the treatment is correct for you.

Hypothyroid & CAD: In fact, if you are truly hyperthyroid (under active thyroid) and not receiving the proper treatment will be detrimental to the heart, especially in setting of previous mi. Proper treatment will help avert the complications associated with untreated hypothyroidism and the heart.

No: That's a low dose generic -- no problem.