Fast heart rate on exertion

[Oldbeforemytime2013]

Hello. I just wanted to know if anyone else suffers with a higher than normal heart rate when walking around or exercising. Both me and my two sisters suffer hypothyroidism (on meds) but I've noticed that our pulse is a lot higher on exertion than other people who don't suffer hypothyroidism. Has anyone else noticed this or can anyone else test this one out and let me know? Thank you all.

[Barb135]

"Both seem to increase round about the time of my period, so my hormones could be playing up as well (even though my hormone blood work came back fine also!)."  You're referring to reproductive hormones?  It's normal for those to fluctuate around the time of your period.

I find that acid reflux was worse on the acid tablets than it is without them.  I often find that taking a couple sips of dill pickle or olive juice helps  most, because the problem isn't really too much acid, it's actually, not enough.

I don't think you're such a mystery; you just need the proper tests and medications.

[Oldbeforemytime2013]

I had an echo on my heart only yesterday and all is fine...just some mild mitral regurgitation but nothing to report on. I do think you're right and I'm going to have to go private! Just hate all these symptoms and not being able to get it sorted! I have reduced my acid tablets to one every other day just to see if this helps. I think it's going to be trial and error for a while. I've been keeping a record of my hr and my ectopic beats. Both seem to increase round about the time of my period, so my hormones could be playing up as well (even though my hormone blood work came back fine also!).
I guess I'm just a mystery, but hope I am able to get it sorted sooner rather than later.

[Barb135]

Have you had a complete heart work up to make sure there's nothing wrong with your heart?

It's not unusual for symptoms to worsen or for new ones to appear when changing med or dosages.

While some people who are hypo have magnesium deficiency, it's not a symptom of hypo, though acid reflux is.

We've had quite a few members on NHS and you're right, for the most part all they test for is TSH and sometimes T4, but that needs to be Free T4, not total.  Many of our members, on NHS, have had to go private in order to get the tests they need. Is that a possibility for you?  Others have jumped through hoops and been able to get to testing/treatment.

If 50 mcg isn't enough and 75 is too much, you could ask to try alternating them for an average of 62.5 and see if that helps.

[Oldbeforemytime2013]

Thanks again for replying. Yes, sorry, I meant mcg! I had been on 50 for 6 weeks. I realise the bloods say I need to increase thyroxine but in 75s I just couldn't function...my hr was so fast all the time, making me dizzy and really breathless. I'm thinking my body just doesn't respond we'll to thyroxine. On NHS (uk) so don't think they test for anything other than tsh and t4.

[Barb135]

Your TSH is higher than it should be.  Your lab is using an outdated range.  The range recommended by AACE over 10 yrs ago is 0.3-3.0.  Labs, therefore, doctors, have been slow to embrace it.

Is the T4 at test for FREE T4 or is it Total T4?  It looks to be total.  If your lab report doesn't specify "Free" then it's total and isn't really very useful.  Of the total T4 in your blood, approximately 90-95% will be bound by protein and is not available for conversion to T3, which is the hormone actually used by individual cells.

You need to ask your doctor to test Free T3 and Free T4, every time you have blood work.

Thyroxine is dosed in mcg, rather than mg, so you mean you are currently on 50 mcg, which was reduced from 75 mcg?

How long had you been on the 50 mcg when those labs were done?

[Oldbeforemytime2013]

Magnesium deficiency was something I was looking at funnily enough! I'm on omeprazole for acid reflux and a side effect of this can be magnesium deficiency. I was also led to believe that magnesium deficiency is a common symptom of hypothyroidism. Still baffled though.

[Oldbeforemytime2013]

My results were tsh 4.2 (range 0.3-5) and my t4 was 17 (11-20). This was with my thyroxine at 50mg. Before this I was on 75 mg and my results were tsh 3.5 and t4 18.9.

[Red_Star]

I meant to say I'm not sure if undiagnosed Hashimoto's thyroiditis was a factor in my high heart rate on the day of the heart monitor test. That may have been solely from magnesium deficiency.

[Red_Star]

I had a 24 hour heart monitor test for my heart rhythm problems (250 to 300 bpm) years ago but on the day of the heart test nothing dramatic was going on.  My highest resting heart rate of the day (could not feel it) was recorded at almost 1pm at 145 bpm.  At that time I had undiagnosed severe magnesium deficiency causing the heart rhythm problems.

I also had undiagnosed Hashimoto's thyroiditis as well but I can't say if that contributed to the higher resting heart rate. Possibly. I was have hyper flare ups on and off but I didn't realise it as the only notable symptoms I had was splinter haemorrages on my nails and a red face (looks like a lupus rash over my cheeks) for about an hour after having a shower.

Now when my heart rate is over 90 bpm it is due to my hyperthyroid flare ups. A resting heart rate above 90 bpm is considered high according to Harvard Medical School.  

[Barb135]

"Perfect" labs don't always mean they are right for you.  It would be helpful to us if you'd post your most current labs, so we can see what might be going on.  Be sure to post reference ranges with any labs, as ranges vary lab to lab and have to come from your own report.  

One thing that happened to me, is that my HR was very low when I was real hypo (upper 40's/low 50's), so when I got on med and my HR started coming up to normal, it felt like it was really rapid, but it was perfectly normal (low-mid 60's... lol).

[Oldbeforemytime2013]

Thanks for posting. I've had all the tests for POTS...all came back negative. I can't really pinpoint anything, so the only I could put it down to is my Thyroid problems! Sometimes feels like I've gone hyper, but bloods are always perfect.

[Red_Star]

POTS is more than 30bpm I meant. :)  

[Red_Star]

Increase in standing heart rate: 0 - 10 bpm is excellent, 10 - 20 bpm is normal, 20 - 30 bpm is cautionary. Postural orthostatic tachycardia syndrome (POTS) is when the heart rate rises 30bpm on standing or to a heart rate greater than 120pbm within 10 minutes of standing. The tilt table test is used to help diagnose POTS.

[Oldbeforemytime2013]

Forgot to mention, more intense exercise and my hr goes to at least 170bpm. I am 32 years old.

[Oldbeforemytime2013]

Thanks for posting. My resting hr is between 70-80, but when I stand up this goes up to  about 96. Just walking from one room to another causes my pulse to go at 120-130 bpm. Had lots of tests done all came back normal! Just wondered if it could simply be a thyroid thing.

[Barb135]

It's normal for heart rate to be increased when exercising.  Exactly how high are the heart rates going?

Normal HR is 60-100, but with intense activity, some may go above 100 for short periods.   For instance, my "resting" HR is around 60, but when I exercise, it might go up to 90 or more, depending on the intensity of the exercise.