I do realize that this thread is about a year old, but I am hoping to get some info from the OP.
Did you find that the mirena caused heartburn? Are you still experiencing it?
I was on the patch for about a year and had horrible heartbrn every month about a week before my period. I stopped the patch and the heartburn magically disappeared. I just got mirena inserted about month ago and the heartburn is back, but seems to be continuous. I, too, was scared that I might be having heart trouble, but now I am convinced that the heartburn is caused by birth control.
Does anyone have any insight into this? I find heartburn/birth control links every now and then, but it doesn't seem to be a common thing.
Thanks in advance for your help!