I don't have chest pain, but my friend does and after many test from the doctors that showed nothing she finally decided to take my advise and take magnesium. Now she is a true believer. Magnesium is what lets your muscles (your heart is a large muscle) relax after contracting (which is calciums job). I take 700-800mg everyday. Just watch out for citrate as too much of this form will cause loose stools and oxide isn't to good.