Hello! Does anybody have any information on the relationship between an underactive thyroid and A Fib, please? I'm newly diagnosed with A Fib. I'm keeping it under control (touch wood) by managing my triggers.
I've had a slightly underactive thyroid for some time. It's not so bad that I need medication but it rumbles along. The nurse at the A Fib clinic mentioned that thyroid issues can have an impact on A Fib, both under and over active. I can see why an over active thyroid would not be good for A Fib but not at all sure about the relationship with an underactive thyroid. Any thoughts/experience would be welcome.
Thank you!
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dunestar
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Yes thyroid problems do cause heart problems, both under and over if not adequately treated will cause palpitations, ectopics and Afib.You need to get hold of your thyroid results, if you have been told you are 'slightly underactive' you should probably be on replacement hormone.
I along with others on the forum have both thyroid disease and Afib and the relationship between the two is well known. I suggest you look at Thyroiduk forum for more insight and post your results for advice.
Thanks Bantam. I should have said that I've posted on Thyroiduk as well. I've had some testing done by Blue Horizon, so got full info. TSH is slightly out of range but T4/T3 in range but on the low side. TPO way out of whack. When you say the relationship is well known did your GP know all about it? My GP was asked by the hospital where I was admitted last Oct to retest as levels of TSH were high when I was admitted with A Fib. So far I've only had a conversation with the pharmacist who only knew about medication for A Fib. That's why I've armed myself with as much data as possible.
I don't rely on my GP to know anything about specialist problems but my Cardiologist is better informed ! If your TSH is over range and you have high antibodies there's not much sense in not treating it but again GPs don't know enough about it !
When we are hypo (and untreated) everything is slowed down so heartrate can be sluggish causing arrhythmias as it struggles to keep going.
I've been both hyper and hypo and believe me neither is easy to sort out, it can be an ongoing battle.
Thanks bantam12. I'll be cheeky and copy the Blue Horizon data to the cardiologist as well as the GP, just so he's informed. My GP already thinks I'm "too analytical" and "trying to be the doctor", so he probably won't like it.
Please give infor about Blue Star - can I get it in the UK. My GP us like yours - considers hypothyroidism not a factor. Yet I've been borderline for 6 years and developed AF 18 months ago
Agree with Bantam although overactive thyroid tends to be more of an issue because it can be more complex to treat. Because under active normally requires thyroid replacement, arguably this is fairly easy to treat but it’s certainly worth checking......
I am in same position as you- no meds needed yet for thyroid. I had more AF while blood pressure was playing up while thyroiditis in play but very little af Now it’s settled down. I am not rushing into replacement for thyroid while blood tests are ok as too much thyroid hormone will definitely get AF going
That's my concern as well. I do want to be treated if necessary but concerned that having too much thyroid hormone will not be good either. I guess starting with a very low dose might be the way to go.
I have both. If your thyroid is under active you will be started on a low dose of Levo according to your age. You should then be tested every six weeks until you slowly build up.
This is interesting. My AF became apparent after my minimum dose thyroxine, which I had been taking for ten years due to a borderline under active thyroid with no ill effects, was suddenly doubled. It was doubled because I was becoming very tired and the pharmacist at the GP surgery concluded it was that my thyroid levels had changed. This sent me into the most terrible period of palpitations snd it was during this time that my AF was discovered. I stopped taking all thyroxine and within two weeks my heart rate had improved dramatically - subsequent tests over the past two years have returned a NORMAL thyroid function!!I can only conclude I never needed it in the first place? I never expected that. I’ve since gone on to radically change my diet and lose three stones and I don’t appear to ever have AF, as far as I’m aware, but still take anticoagulants as per the Cardiologists recommendation.
Hi dunestar, I have been a long term suffer (40years) from Afib and now had 2 ablations at 74. I am now 77 but still get some breakthrough episodes. Indeed I found that hypothyroidism was a problem in these breakthrough eps and attended the thyroid Epi Clinic for investigations. The normal medicine as a replacement hormone worked just toooo well and I ended up with a very high Hyper thyroid and am now trying to have the medicine balanced to try to equalize the problem as it has swung to far hyper. Generally speaking all thyroid issues have an impact on Afib and indeed many other types of arrhythmia. It can be very frustrating to find the correct balance of the medicine. I hope you are successful and I note you are doing much research which can only be to your advantage - notwithstanding the above, we are all of course different and react to thyroid replacement hormones differently. Good luck my friend.
Hi. I had no idea that the two are linked I’ve had under active thyroid for years and on 150 mg of thyroxin daily. Had Afib for nearly 4 years with the usual cardioversions, ablations etc. Finishing up recently with a pacemaker. So it was obviously my thyroid that caused the afib.
I wouldn't say "obviously" as I had had a well medicated stable underactive thyroid for about 12 years prior to the AF starting so they didnt pin the tail on that donkey. My thyroid is now monitored more closely due to the arrhythmia meds so even more under control than previously.
Very interesting comments on thyroid function and aFib. I had my thyroid removed in my 30's ( now 75) due to being grossly enlarged & also underactive. I've been on levo since then. I was diagnosed with aFib late December 2019 after having a stroke. The stroke was thrombolised successfully but I also have other issues with my heart. TBH I don't think the lack of my thyroid has had any effect on my heart.
It's not the lack of a thyroid that effects the heart it's the replacement hormone and whether the dose is correct or not. Being under or over medicated does cause arrhythmias.
I’ve had an under active thyroid for years, and at first was on 50 mcg thyroxine. Then it became overactive, which was horrible, then under again. Now I take 25 mcg and been stable for years🤞. I’ve not been aware of it having any effect on my AF at all, but who knows.
Hello & I have had under active thyroid for 25 years. In 2019 it started affecting my heart & I have had 1 cardioversion. How are your iron and vitamin D levels? I ask because that contributes to less oxygen in blood too (like hypothyroidism). Many manageable things to keep you feeling better. Hang in there and be well!
Thanks Cookie341. I think Vitamin D levels are OK. I've been taking supplements for a while. The Blue Horizon results showed 83 nmol/L. From a thyroid perspective 100 is good but the AFib Cure book recommends 50 - 70 . Not sure about iron although I suspect something might be amiss as I get a bit of restless legs syndrome as well. Awaiting tests results from Medichecks (after I finally summoned up the courage to do the finger prick test). Will definitely be hanging in, so much to keep track of. Keep well yourself.
I went through RLS as well & took lyrica. It worked & restless legs subsided on their own eventually after I went off of Lyrica to try to stop being on so many meds when I ended up in hospital in 2019. That's a tough one, right?! Sleep is important lol.
The meds for RLS scare me to death! But you are right, sleep is important. Thankfully the RLS is only mild (fingers crossed it stays that way). Take care!
Hypothyroidism can be difficult to diagnose. If your blood work shows in normal range you can still be underactive. I had this issue which was not diagnosed until I started taking my basal body temperature before i got out of bed in the morning using an 'old school' thermometer under the tongue. Sure enough my body temp was low and I finally convinced my GP to do a full thyroid panel and, yes, there it was. However, this was not the conclusion I hoped for because my GP's approach was basically to let the thyroid 'die' and then put me on medication. I took a different approach with my naturopath using iodine/selenium/etc. supplementation and it flipped back to normal within 3 months. Bottom line, the blood work doesn't tell the whole story. My Electrophysiologist told me I could have been hyper for a period and then reverted to undiagnosed hypo condition which contributed (caused?) the AF in the first place. This was s my experience 7 years ago. Take care!
Interesting Plantwords, thanks. I think you're right that it seems defeatist to just give up on the thyroid and rely on medication. I have a friend who is heavily into natural approaches and I'm hoping he may be able to help me find a way to address the underlying issue of the autoimmune attacks. Good as well that your EP is clued up on the thyroid side of things.
Yes. My underactive thyroid was pretty stable for years. Blood test every six months to keep track. Then I had two hip replacements six months apart, my thyroid production dropped precipitously and developed Afib bad enough to require cardioversion. As my docs said two things can happen at the same time with no causal relationship. Which came first? Nobody knows.
Plus, 2 hip replacements in that short time would also have caused a heckuva lot of inflammation, which is a known trigger and, I think one of mine as my AF started after I had Achilles tendonitis.
Oh wow Ducky2003! I had thumb tendonitis not so long ago. It sounds very trivial but it was incredibly painful. I would never have thought as it as a trigger for AF, but yes, it makes sense!
Yes, it is painful indeed. I ended up on crutches for 3-4 months, the only advantage of which was going to Silverstone for the F1 GP and having to be golf buggied to and from the grandstand in the rain.😁
Oh crumbs Kiddle, not good. At least you were being tracked well. My surgery is lackadaisical to say the least. That's why I've shelled out about £150 for Blue Horizon tests.
I have had Graves Disease for 4 years now. Hyperthyroidism is WAY more likely to cause AFib but you already know that. Lately I have seen my T4 dip into hypo range while my TSH is in range but climbing. This is a linear relationship so as T4 drops TSH will rise. T3 has the most effect on the heart as it is very potent hormone. It converts from T4 actually to become T3. My new endo who has been on the American Thyroid board for 20 years said TSH is the most likely predicator for AFib Although my T3 and T4 we're usually in range my TSH remained always low. This endo said how you stayed out of AFib last couple years is a miracle with your very low TSH..
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