Overproduction of thyroid hormone by the thyroid gland can cause a rapid heart rate as well as certain types of arrhythmia. The way to test for this is with a blood test that measures the level of thyroid hormone in the blood.
Mike,
You can go to this newsgroup and talk to all kinds of people with thyroid problems:
alt.support.thyroid
JD: HOW DO I GET TO THE NEWSGROUP SUPPORT.THYROID?
THANKS, LIN
Lin:
In Netscape:
Go to your news browser,click on File, click on subscribe, Click on search and type in alt.support.thyroid. If you cannot find it you may need to update your newsgoup. Hope this helps.