Just so others know, this post is over one year old. Nature Throid was reformulated in late fall 2009, early winter 2010. Some people did not respond to the change very well and others moved on to other brands of thyroid replacement with good results.
you should read all of Dr. David Brownsteins books. If you are not responding it may be that your adrenals are not functioning. If the adrenals are down no amount of any form of thyroid will help you. Also, you may need other supplements he talks about like iodine (iodoral 12.5-50mg/day), zinc, selenium, A,C,E, B2,B3,B12 and protein. Stay away from soy, bakery goods, soda pops and gatorade. Detox and drink lots of water. You probably will experience some cleansing crisis' (comes on gradually and lasts several hours to several weeks, it is due to the toxins being stirred up but not yet exiting the body- increase water and temporarily decrease detox agents)and even a healing crisis (comes on suddenly right after a feeling of intense well being and lasts several days to several weeks), but this all means you are actually getting better. You may have a bumpy road ahead, but you cannot give up. Not an option. Good Luck.
Here's a great article conecting PVC's, and Afib to Hypothyroidism (low available thyroid hormone)--remember- t4 is just a storage hormone that must convert to the biologically active thyroid hormone T3--- if this is too low--it can cause issues with the heart for sure.
http://heartdisease.about.com/od/lesscommonheartproblems/a/thyroidheart.htm
Interesting labs after being on the new NT.
4/14 6/11 7/16 range
OLD NT 4-5grains OLD NT 3 grains New NT 4 grains
TSH .02 .03 .02 .34-5.60
FT4 .84 .83 1.01 .58-1.64
FT3 4.43 3.31 3.26 2.39-6.79
I reduced the old NT as I was feeling great but getting severe hand tremors and wanted to see if still felt good at lower dose while getting rid of tremors. Tremors left but didn't feel quite as good. Felt much more hypo on new NT. Interesting that FT4 rose though.
Thanks. Do you have any information about low T3 causing PVCs? I'd love to give it to my uncle. His heart is beating out of rhythm and they are going to shock it to try to get back in order.