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Avatar universal

Abnormal EKG Result - Are My Thyroid Hormone Levels to Blame?

Hello. I am a 42-year-old male, and I have autoimmune hypothyroidism.

From June 2013 to January 2015, I took Synthroid (137 mcg, 3 times per week) (125 mcg, 4 times per week). In January 2015, I had thyroid-related blood tests, and here are the results:

FT4 = 1.45 (normal range = 0.82 - 1.77)

FT3 = 3.2 (normal range = 2.0 - 4.4)

TSH = 0.075 (normal range = 0.450 - 4.500)

Total T4 = 9.5 (normal range = 4.5 - 12.0)

Vitamin B12 = 1189 (normal range = 211 - 946)

My endo thought that my TSH was too low. So, she lowered my Synthroid dosage to (137 mcg, 2 times per week) (125 mcg, 5 times per week).

In May 2015, I had thyroid-related blood tests, and here are the results:

FT4 = 1.49 (normal range = 0.82 - 1.77)

FT3 = 3.3 (normal range = 2.0 - 4.4)

TSH = 0.088 (normal range = 0.450 - 4.500)

Vitamin D, 25-Hydroxy = 9.6 (normal range = 30.0 - 100.0)

Vitamin B12 = 1148 (normal range = 211 - 946)

In August 2015, I was experiencing chest pains and shoulder pains, signs of possible heart trouble. My blood tests from January and May 2015 showed excessive amounts of Vitamin B12, and I read that excess Vitamin B12 could cause heart problems. I stopped taking Vitamin B12, and the pains disappeared. After two weeks, the pains returned. Then the pains declined.

In September 2015, I had thyroid-related blood tests, and here are the results:

FT4 = 1.53 (normal range = 0.82 - 1.77)

FT3 = 3.2 (normal range = 2.0 - 4.4)

TSH = 0.097 (normal range = 0.450 - 4.500)

Vitamin D, 25-Hydroxy = 15.4 (normal range = 30.0 - 100.0)

Vitamin B12 = 700 (normal range = 211 - 946)

In October 2015, I switched from Synthroid to levothyroxine. The levo caused increased chest pains, lightheadedness, and shortness of breath. So, after a week, I went back to Synthroid. The light-headedness and shortness of breath went away. The chest pains declined, but still occurred from time to time.

To find out more about the chest pains, I saw my primary doctor (PCP) in mid-January 2015. He listened to my heart and breathing. The breathing was fine, but my heartbeat was irregular. So, I had an EKG.

The EKG gave the following results:

Sinus Rhythm - frequent PACs (premature atrial beats)

# PACs = 2

-Old anterior infarct    possible septal Q-waves


According to the PCP, there were 2 PACs in 30 seconds.

Also, "old anterior infarct" means that the EKG machine believes that I had a heart attack in the past. The PCP said that it is, indeed, possible for a person to have a heart attack without knowing about it. However, the PCP does NOT believe that I had a heart attack.

Also, the PCP does NOT believe that I have septal Q-waves.

Furthermore, the PCP compared this EKG with my previous EKGs, and he saw that this EKG was similar to the previous ones, which is a good sign.

The PCP believes that my heart issues may stem from too much thyroid hormone in my body.

My own theory is that my heart problems may be a result of too little Vitamin B12.

The PCP does NOT believe that I have significant heart disease or significant heart issues, but he does recommend a stress test on a treadmill and a visit to a cardiologist.

In late-January 2015, I had thyroid-related blood tests, and here are the results:

FT4 = 1.37 (normal range = 0.82 - 1.77)

FT3 = 3.2 (normal range = 2.0 - 4.4)

TSH = 0.100 (normal range = 0.450 - 4.500)

Vitamin D, 25-Hydroxy = 10.9 (normal range = 30.0 - 100.0)

Vitamin B12 = 380 (normal range = 211 - 946)

This is my lowest FT4 level in the past year. My FT3 has been 3.2 or 3.3 for the past year. So, are my thyroid levels too high? Are these levels causing heart issues, such as the abnormal EKG?

My endo says that the thyroid levels are in the normal range and are not too high. But she wants to lower my Synthroid dosage anyway because my TSH is too low. My main concern is to determine what is causing my heart issues. If my thyroid levels are not the cause, why should they be lowered?

My Vitamin B12 level is pretty low, and low B12 levels can cause heart palpitations. Recently, I felt strong heartbeats on my right arm (above the elbow). Are these palpitations? Could my low B12 be causing my heart issues?

Also, a few days ago, I took a warm/hot shower. A few hours after that shower, I lay down to go to sleep, and I felt chest pains. My chest hurt so much that I had trouble falling asleep. This "chest pains when lying down" phenomenon continued for a few days. Is this phenomenon thyroid-related?

Thanks for any assistance.

9 Responses
1756321 tn?1547095325
Excerpt from Cardiac Health - Premature Atrial Contractions (PACs)...

"Causes of PACs

* Stress
* Stimulants
- Caffeine
- Tobacco
- Alcohol
* Underlying Heart Disease
- Hypertension
- Valve disorder
- Previous myocardial infarct
* Abnormal blood levels of magnesium and/or potassium
* Digitalis toxicity"

Just to add, myocardial infarction is the medical term for heart attack.
Avatar universal
Your current FT4 (1.37 [0.82-1.77]) is a little bit on the high side.  It's 58% of range, which is high of the 50% recommended.  FT3 is about as perfect as it gets at 50% of range.  TSH, for what it's worth, is a little low.

Do you have any hyper symptoms (besides the heart issues that are yet to be determined)?

Your vitamin D is still in need of a lot of work, and It's obvious that you needed the B-12 supplement.

I also have had an ECG that said I'd had an MI.  I've had SVT all my life due to WPW syndrome.  During a period of particularly frequent SVT (which in retrospect I suspect was my hyper phase before going hypo), I saw my PCP, who did an ECG.  She sat across from me and insisted I'd have an MI.  I kept telling her that I've had SVT all my life.  She ultimately got a electrophysiologist to look at my ECG, and he immediately knew what was wrong, and that it wasn't an MI.  

Your thyroid labs have been pretty consistent for quite a while.  Chest pains only started in Oct of 2015?  
Avatar universal
My current round of chest pains began in August 2015. However, I did have some significant chest pains in 2012.

I was diagnosed with hypothyroidism in the summer of 2009. In May 2012, I started taking Liothyronine (the generic version of Cytomel). After three days, I was feeling chest and underarm pains, as well as heat. These were symptoms of hyperthyroidism, and my then-endo and I agreed that I should stop the Liothyronine. Unfortunately, the chest pains persisted for quite awhile (maybe a month or more). An EKG showed that I had possible Left Ventricular Hypertrophy (LVH). An echocardiogram showed that there was no LVH. However, the echocardiogram did show trace or trivial regurgitation in three valves, as well as mild atrial dilation.

I discussed all this years ago in the following thread:

www (dot) medhelp (dot) org/posts/Thyroid-Disorders/FT4-to-FT3-Conversion-Problem-----Doctors-Do-Not-Order-Correct-Tests/show/1531317#post_7953234

In the thread, scroll down to the post written by me and dated May 14, 2012.

As for my thyroid-hormone and Vitamin B12 levels, do you believe that I should allow my current endo to lower my Synthroid dosage in order to raise my TSH? My concern is that my FT3 will go too low and that I will be suffering from hypothyroidism. However, after the current endo reduced my Synthroid dosage in January 2015, my FT4 increased and then decreased, but my FT3 stayed the same. So, even if the endo lowers the Synthroid now, the FT3 may still remain the same.

Do you think that I should decrease the Synthroid dosage and resume taking Vitamin B12 at the same time? Or should I first decrease the Synthroid dosage, then wait 6 - 8 weeks, and then resume taking B12?

Avatar universal
Well, I don't smoke tobacco, or drink alcohol, or ingest caffeine. And my blood pressure is low.

A 2012 echocardiogram did show that I have trivial or trace regurgitation in three valves, as well as mild atrial dilation. Also, I am under a lot of stress.

Maybe the PACs in my EKG caused the EKG computer to think that I had had a myocardial infarction, when the cause of the PACs may have been something else entirely.
Avatar universal
"...do you believe that I should allow my current endo to lower my Synthroid dosage in order to raise my TSH?"  If that's the only reason he's lowering your Synthroid, that is never appropriate.  However, your FT4 is a little on the high side, too.  When FT4 is high, the body starts converting more FT4 to RT3 than usual, which could explain why your FT3 stayed the same last time your meds were adjusted.

I'd restart the B-12 despite the decrease in Synthroid.  Your B-12 is way too low at the moment.  If you don't get that back where it belongs, you're going to be wondering which (B-12 deficiency or hypo) is causing your symptoms.
1756321 tn?1547095325
My heart issues were due to severe magnesium deficiency. Stress uses up more magnesium actually so it might be worth trying a good quality magnesium supplement to see if you note an improvement. I take chelated magnesium which is great for absorption.  I do have issues with my kidneys so I have to be careful with magnesium.

Avatar universal
So, let me see if I understand. If my FT4 is level is too high, then the body starts producing more RT3. If the FT3 stays the same and the RT3 increases, then the FT3-to-RT3 ratio will decrease. If that ratio is too low, then the RT3 will interfere with the FT3's ability to work on my body. Is that correct?

By the way, my most recent thyroid-related blood tests (the ones from late-January 2015) included a test for RT3. I paid for that test myself since my endo refused to order it. It took a while for the lab to process the RT3 test, but here is the result:

Reverse T3, Serum       16.1 ng/dL      normal range = 9.2 - 24.1

As a reminder, the Free T3 result is the following:

Free T3                 3.2 pg/mL       normal range = 2.0 - 4.4

I converted both values to pmol/L. Here is the FT3-to-RT3 ratio:

Free T3/Reverse T3  =  (4.915684 pmol/L)  /  (247.321706 pmol/L)

                                  =  .019876

(Free T3/Reverse T3) * 100 = 1.9876     normal range = 1.06 - 2.2

source for normal range:  thyrosynergy (dot) com/t3-reverse-t3-ratio

So, it appears that my RT3 is not too high.

However, my FT3 has been steady at 3.2 or 3.3 for the past year. Perhaps, my current RT3 is not too high, because my current FT4 is my lowest FT4 in the past year. Perhaps in September 2015, when my FT4 was 1.53, my RT3 was higher.

As for Vitamin B12, I've been wondering, just how much is too much? I read the following article on Vitamin B12:

the-moneychanger (dot) com/articles/what_you_dont_know_about_vitamin_b12_can_hurt_you

The author states that the upper limit for Vitamin B12 should be 1300, maybe even 2000. Is this guy correct?

Avatar universal
So, the whole RT3 discussion is controversial, you understand, and this is just my opinion.  When FT4 is high, the body will convert more FT4 to RT4 than it does when FT4 isn't high.  You are correct that all things being equal, this will lower your FT3:RT3 ratio.  Whether RT3 actually interferes with FT3 is an even more controversial subject.  Studies have shown that, in a Petri dish at least, RT3 does not block the action of FT3.  

I appreciate your mathematical rigor.  LOL  However, there's a much easier way to do it!  Some FT3:RT3 ranges are quoted as 1.0-2.0 and some 10-20.  Obviously, this is just off by a factor of 10.  So, all you really have to do is divide your FT3 (3.2) by your RT3 (16.1) , which equals 0.1987.  If you want your ratio between approximately 1.0 and 2.0, multiply by 10.  If you want it between 10 and 20, multiply by 100  Regardless of how you get there, your ratio looks good.

"However, my FT3 has been steady at 3.2 or 3.3 for the past year. Perhaps, my current RT3 is not too high, because my current FT4 is my lowest FT4 in the past year. Perhaps in September 2015, when my FT4 was 1.53, my RT3 was higher. "  Good point.

Let me confess to not reading the whole article on B-12, but I know that many people, especially those with PA, have to have B-12 at the very top or above the range.  The lower limit of our range is ridiculous.  In some countries the lower limit is around 500.  
Avatar universal
In August 2011, my Magnesium RBC result was as follows:

Magnesium RBC    6.8 mg/dL    normal range = 4.2 - 6.8

My test result contained the following disclaimer:

Plasma NOT separated from cells; may falsely decrease RBC Magnesium levels.

In October 2012, I had the following Magnesium results:

Magnesium Serum    2.2 mg/dL   normal range = 1.9 - 2.7

Magnesium RBC      4.8 mg/dL   normal range = 4.0 - 6.4

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Queensland, Australia
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