I am always reading that GPs/Endos. say that excess T3 can cause heart attacks/irregular beats and yet I also read that T3 protects the heart; who is right. Here is a small extract from one of the studies I have read:
Patients with heart disease frequently display a typical pattern of altered thyroid hormone metabolism, characterized by low circulating triiodothyronine (T3) levels in the absence of an intrinsic thyroid disease. This condition, variously known as the “low T3 syndrome” [1], the “nonthyroidal illness syndrome” [2], or the “euthy- roid sick syndrome” [3], is mainly due to the reduced peripheral conversion of T4 into T3 and has been observed in patients with myocardial infarction [4], heart failure [5], and after cardiac operations with and without cardiopulmonary bypass (CPB) [6, 7].
Accepted for publication Jan 14, 2014.
Address correspondence to Dr Cerillo, Operative Unit of Cardiac Surgery, “G. Pasquinucci” Hospital, “G. Monasterio” Foundation, Via Aurelia Sud 54100 Massa, Italy; e-mail: acerillo@yahoo.com.
! 2014 by The Society of Thoracic Surgeons Published by Elsevier
Conclusions. Our study demonstrates that low T3 is a strong predictor of death and low CO in CABG patients. For this reason, the thyroid profile should be evaluated before CABG, and patients with low T3 should be considered at higher risk and treated accordingly.
(Ann Thorac Surg 2014;97:2089–96) ! 2014 by The Society of Thoracic Surgeons
The T3 has a strong influence on the expression of several structural and regulatory proteins of the cardiac myocyte. Because thyroid hormone-regulated transcrip- tion is essential to maintain the physiologic cardiac phenotype, T3 deficiency has been recently proposed as a causative factor in the pathophysiology of heart failure [5, 8]. Furthermore, the low T3 syndrome has been shown to be associated with increased death in the cardiac nonsurgical patient [1, 9]. All these facts led us to hy- pothesize that the presence of a low T3 syndrome at hospital admission, as can be frequently observed in patients undergoing coronary artery bypass grafting
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penny
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I suppose from my point of view, the difficulty is working out whether the body is doing it for good reason for a protective reason or a cause of increased risk. I'm not sure I'd want docs messing with my body when my body invariably knows better than them for the most part. I'd want to know why first before treatment of low T3 was given in these circumstances.
For example, in anorexia, the body forces T3 levels to be low and for good reason. In my own personal experience, my body would not convert T4 for donkeys years and was put on T3 only. When the original problems that existed all that time were fixed, my body now converts T4 into T3 perfectly well. I trust my body did this it also for good reason although I went against it
So I would perhaps believe that it's an indicator of the patients problems being more deep seated than others or perhaps they are simply just iller than those who don't present with low t3 maybe. Just as likely at this point maybe
Hi Saggyuk My body doesnt convert T4 to T3 so I'm on T3 only. What were the 'original problems' that were fixed so your body started converting again? Hope you don't mind me asking. Just interested in case it is relevant to me.
For me it was simply removing the cause of all my inflammation, nutritional deficiencies and health problems - which for me at least after all those years just turned out to be simply removing gluten 100% so worth a try. Too late for my actual thyroid as was dead already but everything else pretty much cleared up sooner or later after a year GF and decreased my thyroid meds by quite a bit
I should add in case gluten not an issue for you, my nutritional deficiencies and other multiple health issues cleared up so not sure what specifically resolved it but when I did a gluten trial my tsh shot up to 50s within six weeks with my serum T3 levels staying the same so was concluded to have a direct effect on my ability to use thyroid hormones and I suppose this is kind of evidence. My inflammation and vitamin blood tests did not go bad so fast so did not correlate but showed inflammation physically round my body so not entirely sure - could be some other random effect elsewhere that cleared up because GF and therefore something else???
Thank you Saggyuk. What is it in the blood test that showed inflammation? My psoraisis has worsened recently and I'm wondering if that is a sign that I have general inflammation elsewhere.
Just the typical inflammatory markers - CRP and ESR although these aren't the be all and end all as you these don't always show it up. For me personally it seems to show up in my CRP which was always over range. Since gluten free, it has been under 1 or even as low as less than 0.1lol. In regards to physical symptoms, it's digestive, I swell up with water retention in my legs, get sleepy, pop up in crazy itchy blisters every where and joints hurt. The blisters are the worst!
I was seeing a cardiologist the year before hyperthyroidism diagnosis. Offered heart ablation if SVTs got more “troublesome”. They did when on T4 but soon put two and two together and realised they were because of poorly treated thyroid disease. Declined cardiologist offer. First combi with T4/10mcgs T3 Endos parting shot as I left was, I quote, “ don’t be surprised if you aren’t in A&E next week with a cardiac arrest”. Now take T3 only and will not be seeing that endo any time soon!
My husbands best friend is a cardiologist and said my Dr did more damage to my heart by not treating my hypo than a lifetime on T3 will. I trust his opinion over any papers trials etc.
High FT3 is always dangerous (values above the normal range) as it mimics hyperthyroidism (overactive thyroid) which has effects on the heart. Low FT3 in heart-related nonthyroidal illness is not necessarily dangerous whilst the condition persists. It is like a "hibernation" mechanism to protect the body against an inappropriately high activity which would strain the heart. However, if the FT3 goes too low, then this predicts that things are worse and there is an increased risk of death.
Just read your response above, and your words "High FT3 is always dangerous". The word "always" concerns me.
As someone who takes a huge dose of T3 and with a much over-range FT3 - because I have a type of thyroid hormone resistance that is only resolved this way (geneticist suggested it could be the result of an as yet unknown variant) - "always" is alarming.
My resting heart rate is around 70/75bpm and my temp is around 36C and I have no symptoms of overmedication.
I understood that under the circumstances high FT3 is to be expected due to (basically) the resistance
I value your work and would be interested to hear your opinion regarding this situation.
I should have said that above-range FT3 in subjects whose conversion ability is normal or good is dangerous. Of course with T3-resistance of any kind this no longer hold, because the serum FT3 doesn't relate closely to cellular T3. And of course there is the "spike" problem where FT3 rises up high shortly after taking T3 and falls back over the next time period of say 12 hours. I don't think this "spike" is necessarily dangerous because the body's response is quite slow and therefore really should be seen as evening out over the whole period ( Function-wise) regardless of the momentary spike. So it's the long term elevation in normal converters that is the worry.
Thank you for clarifying that diogenes . I know I have to be very careful with high dose T3 and wondered if I'd missed something.
After decades of ever declining health, and no success with medics, I am hugely grateful to the experts here who have guided me along the way to improvement. After much reading and advice I'm now almost certain that low -T3 in some form is inherited from my maternal line.
I'm almost 75 and (covid-19 apart) now look forward to a healthier future.
I take NDT and started in October, i had some central chest pain in April which scared me enough to go to A&E at 11pm on a saturday night ( what an education that was). Various tests and xrays later, definately not a heart attack but was invited to chest pain clinic armed with a raft of blood tests at GP first. Lovely cardiac nurse went through everything with a fine tooth comb took full history and i fessed up to the NDT - her reaponse - no interest in it whatsoever as FT3 not over range. Also as my chest pain was in a very specific place and never moved in her opinion (and all my results) it was completely non heart related - probably an isdue with a rib/sternum joint. Just goes to show. I did very thorough research before starting NDT but I still managed to frighten myself silly with that stupid medical myth - NDT/T3 is tantamount to signing your hearts death warrant according to GPs and Endos but apparently not Cardios!!!
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