Thyroid Cyst/Tachycardia

I am a 39 y/o female.  I have high blood pressure that is controled by medication. (I also have a very strong family history of heart disease) One year ago I had an ultrasound of the thyroid and it showed a VERY small cyst.  I recently went back for another US and it is still there, but it has changed shape. I have been having tachycardia at times.  I will be laying in bed watching TV and feel short of breath and palpitations.  When I take my heart rate it is around 140.  My heart rate rarely falls below 90.  One really odd thing about me is that sometimes I will have soooo much energy that it drives me and everyone around me crazy and other times I just can't get out of bed from exhaustion.  I just want to sleep all day.  One minute I think it could be hyperthyroidism and others hypothyroidism.  I have had blood work done that shows my T3, T4, and TSH as normal.  I have heard there are more specific tests you can have done for your thyroid.  
My main question is that am I wrong in thinking the tachycardia could be related to my thyroid?  Why does my energy level fluctuate so extremely? I am suppose to go back to have another US in 3 weeks, but I just wonder if I shouldn't go visit my doctor before then.  Any advice would be greatly appreciated.
Thanks

[Jimlow]

Hi Jazie & Welcome,
Absolutely the symptoms you described can be thyroid related and related directly to your cyst as well. The cyst may actually be what they call a nodule. Nodules happen in both Hashimoto's Thyroiditis (Hypothyroidism/low thyroid) and in Graves Disease (Hyperthyroidism/high thyroid). Since though you have spells of both hyper type symptoms and hypo type symptoms, it could be the Hashimoto's type because a Hashimoto's person will go through periods of switching back & forth between both types symptoms for a while before becoming permanently hypothyroid. It is the thyroid's way of trying to fight off the autoimmune attack, which by the way, both conditions are auotimmune diseases.
I would get the "antibodies" test along with hormone levels because Hashi's can exist in people even when homones are in normal range. Don't let a Dr. tell you otherwise, it is an esablished fact. Unfortunately some Dr.s actually don't know this (also an established fact). The antibody tests are the "Anti-Thyroglobulin and Anti-Peroxidase" Tests. I would tell the Doc I want these done and be firm and not let him talk you out of them. Let us know results if you like, we'll do follow up comments if your antibodies do happen to be elevated.
Christine01, is on this forum too and I hope she will add what she sees needs to be, to my comments (may already have before I click-send on this). She is a really knowlegable person about Hashi's.     BEST WISHES.

[Jimlow]

by the way, I have Hashi's Disease and small nodules. Also went through a period of extreme anxiety/ hyperthyroid symptoms before hypo set in for good. Both my thyroglobulin and peroidase ABs were elevated. Thyroglobulin was "537" (normal range was <40)!

[surgeon]

The opposite from the above post is more likely. A small cyst of the thyroid is not of significance: a cyst means fluid, and it's therefore not a "nodule" in the sense that the above poster has suggested (anything that occupies space is a "nodule" including a cyst. But nodules that do something -- ie produce hormone -- are solid, not cysts. Also, with the tests you describe, it's nearly certain that the tachycardia is NOT due to your thyroid. It is, however, potentially of significance, and could have any number of causes. Your doctor needs to be aware of what's going on and specifically to address the issue of intermittant tachycardia.

[Jimlow]

Jazie,
Surgeon of course is in a much better position to advice you but as on almost ALL FORUMS, we non-medicals have to give input according to personal experience and what we believe a person might benifit from as far as RESEARCH SUGGESTIONS. In reality this is all we regular folks suffering from the disease have however, let me add this; I have an Uncle that had Graves Disease and he had a terrible time getting diagnosed and suffered for a couple years with it, losing almost half his body weight because this Dr. said "labs-normal". He was finally diagnosed and treated and is doing well now 25 years later.
Surgeon, you are appreciated please understand and I promise you this is not a let down of you, I would be a moron to not know you are more knowlegable than us (me), by a long shot but some of where I am coming from is from my own experience of going through FIVE DR.s to finally get proper tests & diagnoses. I was told I HAVE NO NODULES and finally checked for these and were found by my latest Doc. (two of the no-help Docs were "Enocrinologists").
Please bare with our hurts and disappointments, it is not an attack on the entire Medical Profession as a whole! THANK GOD, for the Medical Field, without it, we would really be in trouble. I also feel you are one of the good ones or would not be taking extra time with people like this.
Sometimes we reply to people to uplift them and not necessarily to give the a "cut & dried" answer and they know this. I know what it is like a few years ago to post on a forum and get no reply and this futher embedded a feeling of being "alone' with my disease. We are not Docs and don't pretent to be.
We always wecome your imput, more so than any other but let us express without feeling we've done a wrong. They may doubt all and any part that may be good. Thanks, sincerely.

[Jimlow]

Jazie, a quick add on; as in my reply to you, I used "may be" a nodule. Surgeon used "more likely". Terms like this are used often, so that one particular input is not taken as fact, to exclude all other.

[Jazie]

Thank you so much for everyone's input.  I will call my Doctor tomorrow and talk to her about the tachycardia.  I will also ask about the other blood work.  She is a really good Doctor and I know she will help me persue this until we figure it out.
Thanks
Jazie

[MBFD]

My daughter is 18 and was recently experiencing pain in her neck (Thyroid region) I took her to the Doctor who said her thyroid was a little swollen but she did not think there was anything wrong. She said she was probably coming down with a cold or something, But I insisted we get blood tests. So we did and they cam back TSH 3 - 191. This caused them to  follow- up with Ultrsound and a small complx cyst was found.The Doctor has stated that there is nothing to worry about and she would like to followup in 4 months. with more labs and ultra sound. I am concerned about this. My daughter has lost over 20 pounds in less than 5 weeks and is experiencing strange activities sometimes very wired and full of energy and other times so tired she cannot pick herself up.
Should I insist on a second opinion?
please help

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