Can low FT3 trigger AFib? Help needed please. - Thyroid UK

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Can low FT3 trigger AFib? Help needed please.

DizzyD profile image
13 Replies

Hi all I have literally been trying to compose this post for nine hours which has really stressed me out to the max. My brain is burnt out with the pressure of forcing it to find words to explain things coherently. But I have to push on because I so need some help/support. Please bear with me.

I am trying to figure out what's triggered my recent episode of AFib which has been going on since last night. I am Looking for some possible answers or explanations. My new GP wants to increase arrhythmia meds which is a no, no for me as I am wanting to explore causal factors hopefully with your help.

Looking back, my last (second ever) attack of AFib was January this year when I had covid .

Back then I was on 75mcg levo, despite not having a thyroid due to thyroidectomy 1992, TFT was F T3 at 35% FT4 64%. (Test done mid December) For obvious reasons, February this year I introduced some NDT 15mcg EFRA to the 75mcg levo, (Combo dose) with good results for FT3.

March 2021 TFT

TSH 0.06. 0.27 - 4.2

FT3 6.64 3.1 - 6.8 carried on dosing 15mcg NDT

FT4 25. 12 - 22. Adjusted levo accordingly after I received these results.

Did not get TFT after adjusted dose. Why? I stopped the combo dosing and carried on dosing 75 levothyroxine.

Long story short, initially I was doing fine on combo dose of levo and NDT and was planning on getting a thyroid test after reducing levo (25mcg alternate days), but as time progressed I began to feel dreadful on the combo dose. Reason told me, perhaps I needed to increase NDT but in all honesty I had failed to treat my adrenal problem which has played havoc with all of my NDT trials, so three weeks ago I went back to dosing with 75mcg levo only and started to treat my adrenals, evening/ night time highs with Holy Basil hoping this would improve morning/noon lows given time. My plan was going well. Holy Basil certainly improved my insomnia issue which made a big difference to my quality of life. My long term goal was and still is to eventually dose with NDT or T4 and T3.

Now the setback continual AFib and fluctuating BP up since last night.

Can low FT3 trigger AFib?

I know I could be converting a little T3 from the levo but putting this aside how long would FT3 from the NDT I dosed with three weeks ago he stored in the body?

Perhaps I am ignorant or naive but I suspect any stored T3 in my body has dropped over time since I stopped the NDT, which triggered the AFib flare up. Is this possible?

Furthermore, would dosing with a small amount of synthetic T3 alongside 75mcg levo be of some benefit?

I take the appropriate recommended vitamins to aid conversion. I am undermedicated on 75 of levo. Also I follow the protocol recommended prior to a blood draw.

Sorry for the lengthy post and barrage of questions.

Thank you most sincerely in advance

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DizzyD
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greygoose profile image
greygoose

started to treat my adrenals, evening/ night time highs with Holy Basil hoping this would improve morning/noon lows given time.

That may have improved your sleep, but is unlikely to improve your adrenal problem, because that's not how it works.

As you know, cortisol should be highest in the early morning to get you up out of bed and started on your day. If the adrenals are struggling, they will fail to make their morning quota of cortisol, but they won't stop trying. They will continue to meet that quota until the evening, if necessary, and by then, the cortisol will be high enough to interupt your sleep.

But, lowering the evening level will not help your adrenals to make their quota the next morning - in fact, it might make it more difficult for them. What you need to do is try and increase the morning output, and then the other levels will take care of themselves.

how long would FT3 from the NDT I dosed with three weeks ago he stored in the body?

T3 has a half-life of about 24 hours in the blood (where it doesn't do anything). That means that if you took 10 mcg this morning, by tomorrow morning there will be 5 mcg left, minus what got into the cells. The next day, there will be 2.5, etc. What gets into the cells stays there for around three days before being converted into T2.

Given the small dose of NDT you were taking three weeks ago, there is no chance that any of it would be left in your system now.

And, given the small dose you were taking, I think it highly unlikely that it triggered your AF. The heart needs a lot of T3, so having a low FT3 is not good for it. But whether or not it would trigger AF, I really couldn't say.

Furthermore, would dosing with a small amount of synthetic T3 alongside 75mcg levo be of some benefit?

If you are a poor converter, I'm sure it would be of great benefit. And, it rather looks like you are.

I take the appropriate recommended vitamins to aid conversion.

Sorry, but apart from selenium, there are no recommended vitamins that you can take without getting tested first. We always recommend you test vit D, vit B12, folate and ferritin before supplementing. And, you could add zinc and copper to that list.

Even so, there are many, many reasons for poor conversion, it's not always to do with nutrients. To convert well you also need calories and carbs, and good levels of cortisol, and to be in good health, etc. etc. etc. So, there are no automatic guarantees that optimising your nutrients - whilst a very good thing in itself - is going to improve your conversion.

DizzyD profile image
DizzyD in reply togreygoose

First of all thank you most sincerely for your informative reply, specifically relating to half life of T3. "When the pupil is ready the teacher will appear"!!! you have certainly educated me greygoose which I appreciate so much.

Frankly, I was not expecting any feedback re: adrenals. The information I supplied about adrenal issue was just to add some background info to show where I am at. But still I have taken your comment on board, hence I am literally bewildered now due to varied comments/ info on how to treat adrenals. Personally, I treat the highs with Holy Basil, be it right or wrong because

My main point was/is can low FT3 trigger AFib? Did you get a bit mixed up when you stated that it was highly unlikely that such a small dose of NDT triggered my AFib? Where did this come from? We humans, have to learn to laugh at our mistakes.

greygoose profile image
greygoose in reply toDizzyD

Did you get a bit mixed up when you stated that it was highly unlikely that such a small dose of NDT triggered my AFib?

Not that I'm aware of, no. Although I might have misunderstood something you said.

Perhaps I am ignorant or naive but I suspect any stored T3 in my body has dropped over time since I stopped the NDT, which triggered the AFib flare up.

The way you have written that it sounds as if you thought it was the NDT itself that had triggered the 'AFib flare up', not stopping it. I just took that sentence at face value.

But, I did also say that The heart needs a lot of T3, so having a low FT3 is not good for it. But whether or not it would trigger AF, I really couldn't say. which was my response to your main question.

DizzyD profile image
DizzyD in reply togreygoose

I apologise greygoose I did not get to finish my reply to your comment. Sent incomplete by accident. Yep I agree I am a sloppy writer and I do make mistakes (thank God for that) especially after being sleep deprived and brain dead for 36? hours. Please accept my humble apologises....sorry for not writing my posts word perfect which can be misleading at times.

Really do appreciate your kind help and support. Sincere thank you.

greygoose profile image
greygoose in reply toDizzyD

No apology needed. :)

DizzyD profile image
DizzyD in reply togreygoose

Greygoose good afternoon. Re-read your comments today after a good night's sleep.

What stands out the most is your valid explanation about the half life of T3 which I do understand in principle.

However, I am really baffled after reading two of my most recent TFTs specifically FT3 numbers

Sample 1

TFT 3 March 2021 medichecks.

TSH 0.06. 0.27 - 4.2

FT3 6.64. 3.1. - 6.8

FT4 25. 12 - 22

NOTE: A week before this test I stopped NDT dose of 15mcg Efra. Only dosed with levo 75mcg.

Sample 2

TFT 15 March 2021 GP annual blood test

TSH 0.05. 0.4 - 4.5

FT3 5.6. 2.5 - 6.5

FT4 24.9. 8.0 - 21

NOTE: 20 days before this test I had stopped NDT dose of 15mcg Efra. Only took levo 75mcg.

Greygoose do you have any idea what's happened here regarding half life of T3 ? Any other explanations will be most welcome.

I don't have a thyroid.

Sincere thank you

greygoose profile image
greygoose in reply toDizzyD

No, you may not have a thyroid, but don't forget that even if you are a poor converter, you will be converting some of that T4 into T3 - and you have a lot of T4 to convert!

Not sure what you mean by '15 mcg Erfa'. Do you mean a quarter grain? If so, that was only a teeny-weeny dose of T3 you were taking, anyway, only 2.25 mcg. So, I doubt it contributed much to your FT3 level, anyway.

DizzyD profile image
DizzyD in reply togreygoose

Yes 1/4 of 30mcg EFRA x twice daily...very small dose indeed but despite the half life science and abstinence of NDT periods, prior to tests, the NDT must have contributed to the good ft3 numbers quite significantly. The other option is that I have suddenly become a super converter after years of low ft3. No I am not a super converter, FT3 dropped (has continually done so) from 6.64 to 5.6 as shown in results without that very small dose of NDT.Good grief, cannot imagine what the results would have shown had I been dosing with NDT and levo during the tests.

greygoose profile image
greygoose in reply toDizzyD

Yes 1/4 of 30mcg EFRA x twice daily...very small dose indeed but despite the half life science and abstinence of NDT periods, prior to tests, the NDT must have contributed to the good ft3 numbers quite significantly.

Why? On what do you base that conclusion? I would have thought that the fact that the numbers haven't gone down significantly proves the opposite.

FYI: NDT is measured in grains: 1 grain = 60 mg (not mcg) = approx. 68 mcg T4 + 9 mcg T3. It is important to get the measures right. :)

2.5 mcg T3 would be completely out of your system in a week. What's left is what's coming from conversion. I didn't say anything about being a super-converter, of course you're not. Your results still show poor conversion. But, I cannot understand why you are so against the idea that your FT3 level is due to conversion, not remains of Erfa tucked away in secret places. The only people that don't convert at all are corpses.

Or, maybe, I've just completely misunderstood your question?

radd profile image
radd

DizzyD,

NDT can be intolerant of cortisol issues and having COVID might have increased adrenal issues further.

T3 has a short half life but biological effects can last up to 24 hours. Low T3 can cause or increase Afib - see link below for paper posted by tattybogle last week that explains how both T4 & T3 influence the heart.

FT4 64% & FT3 at 35% on 75mcg Levo looks like you are a poor converter and allows room for a little T3 to be added. Synthetic T3 will allow for minor dose increments that adrenals can slowly adjust to.

Maybe start with just 2.5mcg in the am for a week or so and see how you feel before adding 2.5mcg in the pm. Multi-dosing is kinder to the body because will reduce rapidly of T3 onset and prolong the duration of its action.

NDT 15mcg EFRA is a tiny T3 dose & your FT3 levels rose adequately so I wouldn't go any more than 5mcg T3 initially before testing after six weeks to ensure you don't overstep your sweet spot.

Low iron is a common reason for Afib so ensure adequate levels, along with VitB12, folate & Vit D, & supplementing Vit C is good for adrenals.

.

gponline.com/endocrinology-...

DizzyD profile image
DizzyD in reply toradd

Ohh that's brilliant advice radd. You have made my day honestly. Have not read the link you sent yet...saving it for later. So pleased you have confirmed my suspicion that low T3 can trigger AFib. Defo going to take small doses of T3 as you suggested. My iron intake, supplements and diet, liver, spinach etc is good. Supplement with beef liver caps also and vit D, b complex, selenium, magnesium Vit C, k2. Sincere thanks you.

Triciatextiles profile image
Triciatextiles

Hi

I have AFib and like you have been experimenting with levo and T3 and now Metavive. What I have learnt is that I cannot tolerate any synthetic T3 and I have tried just a very small dose of 2.5mg on a number of occassions but it sent my heart rate to over 80bpm which is far too high for me. My AFib is triggered by high blood pressure which I believe is triggered by low thyroid hormones. I know this because when I have increased Levo my blood pressure drops although it still remains a little high. I need Levo to maintain my blood pressure to a reasonable level so I don't have an attack of AFib, I also find that it remains more consistent for my body but I cannot tolerant more than 75/100mg per day. Why did you reduce Levo and not the NDT? you could consider reducing NDT and increasing Levo.

Do you take beta blockers ? these do interfere with the take up of Levo. You could consider an increase in your medication for AFIb as a 'pill in the pocket' if you don't wish to take this every day, (I do this) something to discuss with your GP.

DizzyD profile image
DizzyD

Hi Tricia sorry to hear you cannot tolerant T3. I have no idea what Metavive is but I will look it up. Considering I have dosed with NDT I think I will be ok dosing with small amounts of T3 as so kindly suggested by radd. I reduced levo instead of NDT because my FT4 was out of range (too high) and FT3 was ideally placed just below top of range. There was no need to reduce NDT according to My results. Besides, I was on a very small dose of NDT levo needed to be reduced.I do take a beta blocker bisoprolol which is a selective BB that targets the heart. As of yet, I have not found any info which states that bisoprolol disrupts absorption of levo. Propranolol, on the other hand is a non selective beta blocker and there are many reports claiming that it adversely effects levo absorption.

Over the past few months I have been reducing beta blocker from 2.5 to 1.25 with no problem. Somedays, I forgot to take it. All was well I been on 1.25 for past four weeks. Since last night, AFib flare up, i have dosed with 2.5 again but it has done nothing to stop the aFib. Perhaps it has reduced the intensity of the arrhythmias. Like yourself, my ideal treatment would be a pill in the pocket. I still waiting to see a cardiologist then I will request it.

Thank you for your feedback. Have a rewarding evening

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